4978 lines
134 KiB
C
4978 lines
134 KiB
C
/*-------------------------------------------------------------------------
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*
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* postmaster.c
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* This program acts as a clearing house for requests to the
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* POSTGRES system. Frontend programs send a startup message
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* to the Postmaster and the postmaster uses the info in the
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* message to setup a backend process.
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*
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* The postmaster also manages system-wide operations such as
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* startup and shutdown. The postmaster itself doesn't do those
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* operations, mind you --- it just forks off a subprocess to do them
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* at the right times. It also takes care of resetting the system
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* if a backend crashes.
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*
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* The postmaster process creates the shared memory and semaphore
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* pools during startup, but as a rule does not touch them itself.
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* In particular, it is not a member of the PGPROC array of backends
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* and so it cannot participate in lock-manager operations. Keeping
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* the postmaster away from shared memory operations makes it simpler
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* and more reliable. The postmaster is almost always able to recover
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* from crashes of individual backends by resetting shared memory;
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* if it did much with shared memory then it would be prone to crashing
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* along with the backends.
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*
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* When a request message is received, we now fork() immediately.
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* The child process performs authentication of the request, and
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* then becomes a backend if successful. This allows the auth code
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* to be written in a simple single-threaded style (as opposed to the
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* crufty "poor man's multitasking" code that used to be needed).
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* More importantly, it ensures that blockages in non-multithreaded
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* libraries like SSL or PAM cannot cause denial of service to other
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* clients.
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*
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*
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* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.607 2010/05/14 18:08:33 rhaas Exp $
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*
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* NOTES
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*
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* Initialization:
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* The Postmaster sets up shared memory data structures
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* for the backends.
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*
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* Synchronization:
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* The Postmaster shares memory with the backends but should avoid
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* touching shared memory, so as not to become stuck if a crashing
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* backend screws up locks or shared memory. Likewise, the Postmaster
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* should never block on messages from frontend clients.
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*
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* Garbage Collection:
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* The Postmaster cleans up after backends if they have an emergency
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* exit and/or core dump.
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*
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* Error Reporting:
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* Use write_stderr() only for reporting "interactive" errors
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* (essentially, bogus arguments on the command line). Once the
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* postmaster is launched, use ereport(). In particular, don't use
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* write_stderr() for anything that occurs after pmdaemonize.
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include <unistd.h>
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#include <signal.h>
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#include <time.h>
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#include <sys/wait.h>
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#include <ctype.h>
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#include <sys/stat.h>
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#include <sys/socket.h>
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#include <fcntl.h>
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#include <sys/param.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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#include <netdb.h>
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#include <limits.h>
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#ifdef HAVE_SYS_SELECT_H
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#include <sys/select.h>
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#endif
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#ifdef HAVE_GETOPT_H
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#include <getopt.h>
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#endif
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#ifdef USE_BONJOUR
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#include <dns_sd.h>
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#endif
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#include "access/transam.h"
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#include "access/xlog.h"
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#include "bootstrap/bootstrap.h"
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#include "catalog/pg_control.h"
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#include "lib/dllist.h"
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#include "libpq/auth.h"
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#include "libpq/ip.h"
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#include "libpq/libpq.h"
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#include "libpq/pqsignal.h"
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#include "miscadmin.h"
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#include "pgstat.h"
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#include "postmaster/autovacuum.h"
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#include "postmaster/fork_process.h"
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#include "postmaster/pgarch.h"
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#include "postmaster/postmaster.h"
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#include "postmaster/syslogger.h"
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#include "replication/walsender.h"
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#include "storage/fd.h"
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#include "storage/ipc.h"
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#include "storage/pg_shmem.h"
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#include "storage/pmsignal.h"
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#include "storage/proc.h"
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#include "tcop/tcopprot.h"
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#include "utils/builtins.h"
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#include "utils/datetime.h"
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#include "utils/memutils.h"
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#include "utils/ps_status.h"
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#ifdef EXEC_BACKEND
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#include "storage/spin.h"
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#endif
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/*
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* List of active backends (or child processes anyway; we don't actually
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* know whether a given child has become a backend or is still in the
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* authorization phase). This is used mainly to keep track of how many
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* children we have and send them appropriate signals when necessary.
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*
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* "Special" children such as the startup, bgwriter and autovacuum launcher
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* tasks are not in this list. Autovacuum worker and walsender processes are
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* in it. Also, "dead_end" children are in it: these are children launched just
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* for the purpose of sending a friendly rejection message to a would-be
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* client. We must track them because they are attached to shared memory,
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* but we know they will never become live backends. dead_end children are
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* not assigned a PMChildSlot.
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*/
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typedef struct bkend
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{
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pid_t pid; /* process id of backend */
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long cancel_key; /* cancel key for cancels for this backend */
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int child_slot; /* PMChildSlot for this backend, if any */
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bool is_autovacuum; /* is it an autovacuum process? */
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bool dead_end; /* is it going to send an error and quit? */
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Dlelem elem; /* list link in BackendList */
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} Backend;
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static Dllist *BackendList;
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#ifdef EXEC_BACKEND
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static Backend *ShmemBackendArray;
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#endif
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/* The socket number we are listening for connections on */
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int PostPortNumber;
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char *UnixSocketDir;
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char *ListenAddresses;
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/*
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* ReservedBackends is the number of backends reserved for superuser use.
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* This number is taken out of the pool size given by MaxBackends so
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* number of backend slots available to non-superusers is
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* (MaxBackends - ReservedBackends). Note what this really means is
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* "if there are <= ReservedBackends connections available, only superusers
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* can make new connections" --- pre-existing superuser connections don't
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* count against the limit.
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*/
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int ReservedBackends;
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/* The socket(s) we're listening to. */
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#define MAXLISTEN 64
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static pgsocket ListenSocket[MAXLISTEN];
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/*
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* Set by the -o option
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*/
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static char ExtraOptions[MAXPGPATH];
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/*
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* These globals control the behavior of the postmaster in case some
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* backend dumps core. Normally, it kills all peers of the dead backend
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* and reinitializes shared memory. By specifying -s or -n, we can have
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* the postmaster stop (rather than kill) peers and not reinitialize
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* shared data structures. (Reinit is currently dead code, though.)
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*/
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static bool Reinit = true;
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static int SendStop = false;
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/* still more option variables */
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bool EnableSSL = false;
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bool SilentMode = false; /* silent_mode */
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int PreAuthDelay = 0;
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int AuthenticationTimeout = 60;
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bool log_hostname; /* for ps display and logging */
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bool Log_connections = false;
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bool Db_user_namespace = false;
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bool enable_bonjour = false;
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char *bonjour_name;
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/* PIDs of special child processes; 0 when not running */
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static pid_t StartupPID = 0,
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BgWriterPID = 0,
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WalWriterPID = 0,
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WalReceiverPID = 0,
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AutoVacPID = 0,
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PgArchPID = 0,
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PgStatPID = 0,
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SysLoggerPID = 0;
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/* Startup/shutdown state */
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#define NoShutdown 0
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#define SmartShutdown 1
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#define FastShutdown 2
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static int Shutdown = NoShutdown;
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static bool FatalError = false; /* T if recovering from backend crash */
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static bool RecoveryError = false; /* T if WAL recovery failed */
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/*
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* We use a simple state machine to control startup, shutdown, and
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* crash recovery (which is rather like shutdown followed by startup).
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*
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* After doing all the postmaster initialization work, we enter PM_STARTUP
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* state and the startup process is launched. The startup process begins by
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* reading the control file and other preliminary initialization steps.
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* In a normal startup, or after crash recovery, the startup process exits
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* with exit code 0 and we switch to PM_RUN state. However, archive recovery
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* is handled specially since it takes much longer and we would like to support
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* hot standby during archive recovery.
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*
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* When the startup process is ready to start archive recovery, it signals the
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* postmaster, and we switch to PM_RECOVERY state. The background writer is
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* launched, while the startup process continues applying WAL. If Hot Standby
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* is enabled, then, after reaching a consistent point in WAL redo, startup
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* process signals us again, and we switch to PM_RECOVERY_CONSISTENT state and
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* begin accepting connections to perform read-only queries. When archive
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* recovery is finished, the startup process exits with exit code 0 and we
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* switch to PM_RUN state.
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*
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* Normal child backends can only be launched when we are in PM_RUN or
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* PM_RECOVERY_CONSISTENT state. (We also allow launch of normal
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* child backends in PM_WAIT_BACKUP state, but only for superusers.)
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* In other states we handle connection requests by launching "dead_end"
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* child processes, which will simply send the client an error message and
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* quit. (We track these in the BackendList so that we can know when they
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* are all gone; this is important because they're still connected to shared
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* memory, and would interfere with an attempt to destroy the shmem segment,
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* possibly leading to SHMALL failure when we try to make a new one.)
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* In PM_WAIT_DEAD_END state we are waiting for all the dead_end children
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* to drain out of the system, and therefore stop accepting connection
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* requests at all until the last existing child has quit (which hopefully
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* will not be very long).
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*
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* Notice that this state variable does not distinguish *why* we entered
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* states later than PM_RUN --- Shutdown and FatalError must be consulted
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* to find that out. FatalError is never true in PM_RECOVERY_* or PM_RUN
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* states, nor in PM_SHUTDOWN states (because we don't enter those states
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* when trying to recover from a crash). It can be true in PM_STARTUP state,
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* because we don't clear it until we've successfully started WAL redo.
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* Similarly, RecoveryError means that we have crashed during recovery, and
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* should not try to restart.
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*/
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typedef enum
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{
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PM_INIT, /* postmaster starting */
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PM_STARTUP, /* waiting for startup subprocess */
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PM_RECOVERY, /* in archive recovery mode */
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PM_RECOVERY_CONSISTENT, /* consistent recovery mode */
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PM_RUN, /* normal "database is alive" state */
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PM_WAIT_BACKUP, /* waiting for online backup mode to end */
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PM_WAIT_READONLY, /* waiting for read only backends to exit */
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PM_WAIT_BACKENDS, /* waiting for live backends to exit */
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PM_SHUTDOWN, /* waiting for bgwriter to do shutdown ckpt */
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PM_SHUTDOWN_2, /* waiting for archiver and walsenders to
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* finish */
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PM_WAIT_DEAD_END, /* waiting for dead_end children to exit */
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PM_NO_CHILDREN /* all important children have exited */
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} PMState;
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static PMState pmState = PM_INIT;
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bool ClientAuthInProgress = false; /* T during new-client
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* authentication */
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bool redirection_done = false; /* stderr redirected for syslogger? */
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/* received START_AUTOVAC_LAUNCHER signal */
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static volatile sig_atomic_t start_autovac_launcher = false;
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/* the launcher needs to be signalled to communicate some condition */
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static volatile bool avlauncher_needs_signal = false;
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/*
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* State for assigning random salts and cancel keys.
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* Also, the global MyCancelKey passes the cancel key assigned to a given
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* backend from the postmaster to that backend (via fork).
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*/
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static unsigned int random_seed = 0;
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static struct timeval random_start_time;
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extern char *optarg;
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extern int optind,
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opterr;
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#ifdef HAVE_INT_OPTRESET
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extern int optreset; /* might not be declared by system headers */
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#endif
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#ifdef USE_BONJOUR
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static DNSServiceRef bonjour_sdref = NULL;
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#endif
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/*
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* postmaster.c - function prototypes
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*/
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static void getInstallationPaths(const char *argv0);
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static void checkDataDir(void);
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static void pmdaemonize(void);
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static Port *ConnCreate(int serverFd);
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static void ConnFree(Port *port);
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static void reset_shared(int port);
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static void SIGHUP_handler(SIGNAL_ARGS);
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static void pmdie(SIGNAL_ARGS);
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static void reaper(SIGNAL_ARGS);
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static void sigusr1_handler(SIGNAL_ARGS);
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static void startup_die(SIGNAL_ARGS);
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static void dummy_handler(SIGNAL_ARGS);
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static void CleanupBackend(int pid, int exitstatus);
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static void HandleChildCrash(int pid, int exitstatus, const char *procname);
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static void LogChildExit(int lev, const char *procname,
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int pid, int exitstatus);
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static void PostmasterStateMachine(void);
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static void BackendInitialize(Port *port);
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static int BackendRun(Port *port);
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static void ExitPostmaster(int status);
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static int ServerLoop(void);
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static int BackendStartup(Port *port);
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static int ProcessStartupPacket(Port *port, bool SSLdone);
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static void processCancelRequest(Port *port, void *pkt);
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static int initMasks(fd_set *rmask);
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static void report_fork_failure_to_client(Port *port, int errnum);
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static enum CAC_state canAcceptConnections(void);
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static long PostmasterRandom(void);
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static void RandomSalt(char *md5Salt);
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static void signal_child(pid_t pid, int signal);
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static bool SignalSomeChildren(int signal, int targets);
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#define SignalChildren(sig) SignalSomeChildren(sig, BACKEND_TYPE_ALL)
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#define SignalAutovacWorkers(sig) SignalSomeChildren(sig, BACKEND_TYPE_AUTOVAC)
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/*
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* Possible types of a backend. These are OR-able request flag bits
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* for SignalSomeChildren() and CountChildren().
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*/
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#define BACKEND_TYPE_NORMAL 0x0001 /* normal backend */
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#define BACKEND_TYPE_AUTOVAC 0x0002 /* autovacuum worker process */
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#define BACKEND_TYPE_WALSND 0x0004 /* walsender process */
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#define BACKEND_TYPE_ALL 0x0007 /* OR of all the above */
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static int CountChildren(int target);
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static bool CreateOptsFile(int argc, char *argv[], char *fullprogname);
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static pid_t StartChildProcess(AuxProcType type);
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static void StartAutovacuumWorker(void);
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#ifdef EXEC_BACKEND
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#ifdef WIN32
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static pid_t win32_waitpid(int *exitstatus);
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static void WINAPI pgwin32_deadchild_callback(PVOID lpParameter, BOOLEAN TimerOrWaitFired);
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static HANDLE win32ChildQueue;
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typedef struct
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{
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HANDLE waitHandle;
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HANDLE procHandle;
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DWORD procId;
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} win32_deadchild_waitinfo;
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HANDLE PostmasterHandle;
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#endif
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static pid_t backend_forkexec(Port *port);
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static pid_t internal_forkexec(int argc, char *argv[], Port *port);
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/* Type for a socket that can be inherited to a client process */
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#ifdef WIN32
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typedef struct
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{
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SOCKET origsocket; /* Original socket value, or PGINVALID_SOCKET
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* if not a socket */
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WSAPROTOCOL_INFO wsainfo;
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} InheritableSocket;
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#else
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typedef int InheritableSocket;
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#endif
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typedef struct LWLock LWLock; /* ugly kluge */
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/*
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* Structure contains all variables passed to exec:ed backends
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*/
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typedef struct
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{
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Port port;
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InheritableSocket portsocket;
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char DataDir[MAXPGPATH];
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pgsocket ListenSocket[MAXLISTEN];
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long MyCancelKey;
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int MyPMChildSlot;
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#ifndef WIN32
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unsigned long UsedShmemSegID;
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#else
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HANDLE UsedShmemSegID;
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#endif
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void *UsedShmemSegAddr;
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slock_t *ShmemLock;
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VariableCache ShmemVariableCache;
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Backend *ShmemBackendArray;
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LWLock *LWLockArray;
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slock_t *ProcStructLock;
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PROC_HDR *ProcGlobal;
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PGPROC *AuxiliaryProcs;
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PMSignalData *PMSignalState;
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InheritableSocket pgStatSock;
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pid_t PostmasterPid;
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TimestampTz PgStartTime;
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TimestampTz PgReloadTime;
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bool redirection_done;
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#ifdef WIN32
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HANDLE PostmasterHandle;
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HANDLE initial_signal_pipe;
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HANDLE syslogPipe[2];
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#else
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int syslogPipe[2];
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#endif
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char my_exec_path[MAXPGPATH];
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char pkglib_path[MAXPGPATH];
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char ExtraOptions[MAXPGPATH];
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} BackendParameters;
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static void read_backend_variables(char *id, Port *port);
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static void restore_backend_variables(BackendParameters *param, Port *port);
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#ifndef WIN32
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static bool save_backend_variables(BackendParameters *param, Port *port);
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#else
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static bool save_backend_variables(BackendParameters *param, Port *port,
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HANDLE childProcess, pid_t childPid);
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#endif
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static void ShmemBackendArrayAdd(Backend *bn);
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static void ShmemBackendArrayRemove(Backend *bn);
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#endif /* EXEC_BACKEND */
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#define StartupDataBase() StartChildProcess(StartupProcess)
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#define StartBackgroundWriter() StartChildProcess(BgWriterProcess)
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#define StartWalWriter() StartChildProcess(WalWriterProcess)
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#define StartWalReceiver() StartChildProcess(WalReceiverProcess)
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|
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/* Macros to check exit status of a child process */
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#define EXIT_STATUS_0(st) ((st) == 0)
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#define EXIT_STATUS_1(st) (WIFEXITED(st) && WEXITSTATUS(st) == 1)
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/*
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* Postmaster main entry point
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*/
|
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int
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PostmasterMain(int argc, char *argv[])
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{
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int opt;
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int status;
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char *userDoption = NULL;
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int i;
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MyProcPid = PostmasterPid = getpid();
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MyStartTime = time(NULL);
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IsPostmasterEnvironment = true;
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/*
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* for security, no dir or file created can be group or other accessible
|
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*/
|
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umask((mode_t) 0077);
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|
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/*
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* Fire up essential subsystems: memory management
|
|
*/
|
|
MemoryContextInit();
|
|
|
|
/*
|
|
* By default, palloc() requests in the postmaster will be allocated in
|
|
* the PostmasterContext, which is space that can be recycled by backends.
|
|
* Allocated data that needs to be available to backends should be
|
|
* allocated in TopMemoryContext.
|
|
*/
|
|
PostmasterContext = AllocSetContextCreate(TopMemoryContext,
|
|
"Postmaster",
|
|
ALLOCSET_DEFAULT_MINSIZE,
|
|
ALLOCSET_DEFAULT_INITSIZE,
|
|
ALLOCSET_DEFAULT_MAXSIZE);
|
|
MemoryContextSwitchTo(PostmasterContext);
|
|
|
|
/* Initialize paths to installation files */
|
|
getInstallationPaths(argv[0]);
|
|
|
|
/*
|
|
* Options setup
|
|
*/
|
|
InitializeGUCOptions();
|
|
|
|
opterr = 1;
|
|
|
|
/*
|
|
* Parse command-line options. CAUTION: keep this in sync with
|
|
* tcop/postgres.c (the option sets should not conflict) and with the
|
|
* common help() function in main/main.c.
|
|
*/
|
|
while ((opt = getopt(argc, argv, "A:B:c:D:d:EeFf:h:ijk:lN:nOo:Pp:r:S:sTt:W:-:")) != -1)
|
|
{
|
|
switch (opt)
|
|
{
|
|
case 'A':
|
|
SetConfigOption("debug_assertions", optarg, PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'B':
|
|
SetConfigOption("shared_buffers", optarg, PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'D':
|
|
userDoption = optarg;
|
|
break;
|
|
|
|
case 'd':
|
|
set_debug_options(atoi(optarg), PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'E':
|
|
SetConfigOption("log_statement", "all", PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'e':
|
|
SetConfigOption("datestyle", "euro", PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'F':
|
|
SetConfigOption("fsync", "false", PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'f':
|
|
if (!set_plan_disabling_options(optarg, PGC_POSTMASTER, PGC_S_ARGV))
|
|
{
|
|
write_stderr("%s: invalid argument for option -f: \"%s\"\n",
|
|
progname, optarg);
|
|
ExitPostmaster(1);
|
|
}
|
|
break;
|
|
|
|
case 'h':
|
|
SetConfigOption("listen_addresses", optarg, PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'i':
|
|
SetConfigOption("listen_addresses", "*", PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'j':
|
|
/* only used by interactive backend */
|
|
break;
|
|
|
|
case 'k':
|
|
SetConfigOption("unix_socket_directory", optarg, PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'l':
|
|
SetConfigOption("ssl", "true", PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'N':
|
|
SetConfigOption("max_connections", optarg, PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'n':
|
|
/* Don't reinit shared mem after abnormal exit */
|
|
Reinit = false;
|
|
break;
|
|
|
|
case 'O':
|
|
SetConfigOption("allow_system_table_mods", "true", PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'o':
|
|
/* Other options to pass to the backend on the command line */
|
|
snprintf(ExtraOptions + strlen(ExtraOptions),
|
|
sizeof(ExtraOptions) - strlen(ExtraOptions),
|
|
" %s", optarg);
|
|
break;
|
|
|
|
case 'P':
|
|
SetConfigOption("ignore_system_indexes", "true", PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'p':
|
|
SetConfigOption("port", optarg, PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'r':
|
|
/* only used by single-user backend */
|
|
break;
|
|
|
|
case 'S':
|
|
SetConfigOption("work_mem", optarg, PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 's':
|
|
SetConfigOption("log_statement_stats", "true", PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'T':
|
|
|
|
/*
|
|
* In the event that some backend dumps core, send SIGSTOP,
|
|
* rather than SIGQUIT, to all its peers. This lets the wily
|
|
* post_hacker collect core dumps from everyone.
|
|
*/
|
|
SendStop = true;
|
|
break;
|
|
|
|
case 't':
|
|
{
|
|
const char *tmp = get_stats_option_name(optarg);
|
|
|
|
if (tmp)
|
|
{
|
|
SetConfigOption(tmp, "true", PGC_POSTMASTER, PGC_S_ARGV);
|
|
}
|
|
else
|
|
{
|
|
write_stderr("%s: invalid argument for option -t: \"%s\"\n",
|
|
progname, optarg);
|
|
ExitPostmaster(1);
|
|
}
|
|
break;
|
|
}
|
|
|
|
case 'W':
|
|
SetConfigOption("post_auth_delay", optarg, PGC_POSTMASTER, PGC_S_ARGV);
|
|
break;
|
|
|
|
case 'c':
|
|
case '-':
|
|
{
|
|
char *name,
|
|
*value;
|
|
|
|
ParseLongOption(optarg, &name, &value);
|
|
if (!value)
|
|
{
|
|
if (opt == '-')
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("--%s requires a value",
|
|
optarg)));
|
|
else
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("-c %s requires a value",
|
|
optarg)));
|
|
}
|
|
|
|
SetConfigOption(name, value, PGC_POSTMASTER, PGC_S_ARGV);
|
|
free(name);
|
|
if (value)
|
|
free(value);
|
|
break;
|
|
}
|
|
|
|
default:
|
|
write_stderr("Try \"%s --help\" for more information.\n",
|
|
progname);
|
|
ExitPostmaster(1);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Postmaster accepts no non-option switch arguments.
|
|
*/
|
|
if (optind < argc)
|
|
{
|
|
write_stderr("%s: invalid argument: \"%s\"\n",
|
|
progname, argv[optind]);
|
|
write_stderr("Try \"%s --help\" for more information.\n",
|
|
progname);
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
/*
|
|
* Locate the proper configuration files and data directory, and read
|
|
* postgresql.conf for the first time.
|
|
*/
|
|
if (!SelectConfigFiles(userDoption, progname))
|
|
ExitPostmaster(2);
|
|
|
|
/* Verify that DataDir looks reasonable */
|
|
checkDataDir();
|
|
|
|
/* And switch working directory into it */
|
|
ChangeToDataDir();
|
|
|
|
/*
|
|
* Check for invalid combinations of GUC settings.
|
|
*/
|
|
if (ReservedBackends >= MaxBackends)
|
|
{
|
|
write_stderr("%s: superuser_reserved_connections must be less than max_connections\n", progname);
|
|
ExitPostmaster(1);
|
|
}
|
|
if (XLogArchiveMode && wal_level == WAL_LEVEL_MINIMAL)
|
|
ereport(ERROR,
|
|
(errmsg("WAL archival (archive_mode='on') requires wal_level 'archive' or 'hot_standby'")));
|
|
if (max_wal_senders > 0 && wal_level == WAL_LEVEL_MINIMAL)
|
|
ereport(ERROR,
|
|
(errmsg("WAL streaming (max_wal_senders > 0) requires wal_level 'archive' or 'hot_standby")));
|
|
|
|
/*
|
|
* Other one-time internal sanity checks can go here, if they are fast.
|
|
* (Put any slow processing further down, after postmaster.pid creation.)
|
|
*/
|
|
if (!CheckDateTokenTables())
|
|
{
|
|
write_stderr("%s: invalid datetoken tables, please fix\n", progname);
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
/*
|
|
* Now that we are done processing the postmaster arguments, reset
|
|
* getopt(3) library so that it will work correctly in subprocesses.
|
|
*/
|
|
optind = 1;
|
|
#ifdef HAVE_INT_OPTRESET
|
|
optreset = 1; /* some systems need this too */
|
|
#endif
|
|
|
|
/* For debugging: display postmaster environment */
|
|
{
|
|
extern char **environ;
|
|
char **p;
|
|
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("%s: PostmasterMain: initial environ dump:",
|
|
progname)));
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("-----------------------------------------")));
|
|
for (p = environ; *p; ++p)
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("\t%s", *p)));
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("-----------------------------------------")));
|
|
}
|
|
|
|
/*
|
|
* Fork away from controlling terminal, if silent_mode specified.
|
|
*
|
|
* Must do this before we grab any interlock files, else the interlocks
|
|
* will show the wrong PID.
|
|
*/
|
|
if (SilentMode)
|
|
pmdaemonize();
|
|
|
|
/*
|
|
* Create lockfile for data directory.
|
|
*
|
|
* We want to do this before we try to grab the input sockets, because the
|
|
* data directory interlock is more reliable than the socket-file
|
|
* interlock (thanks to whoever decided to put socket files in /tmp :-().
|
|
* For the same reason, it's best to grab the TCP socket(s) before the
|
|
* Unix socket.
|
|
*/
|
|
CreateDataDirLockFile(true);
|
|
|
|
/*
|
|
* If timezone is not set, determine what the OS uses. (In theory this
|
|
* should be done during GUC initialization, but because it can take as
|
|
* much as several seconds, we delay it until after we've created the
|
|
* postmaster.pid file. This prevents problems with boot scripts that
|
|
* expect the pidfile to appear quickly. Also, we avoid problems with
|
|
* trying to locate the timezone files too early in initialization.)
|
|
*/
|
|
pg_timezone_initialize();
|
|
|
|
/*
|
|
* Likewise, init timezone_abbreviations if not already set.
|
|
*/
|
|
pg_timezone_abbrev_initialize();
|
|
|
|
/*
|
|
* Initialize SSL library, if specified.
|
|
*/
|
|
#ifdef USE_SSL
|
|
if (EnableSSL)
|
|
secure_initialize();
|
|
#endif
|
|
|
|
/*
|
|
* process any libraries that should be preloaded at postmaster start
|
|
*/
|
|
process_shared_preload_libraries();
|
|
|
|
/*
|
|
* Remove old temporary files. At this point there can be no other
|
|
* Postgres processes running in this directory, so this should be safe.
|
|
*/
|
|
RemovePgTempFiles();
|
|
|
|
/*
|
|
* Establish input sockets.
|
|
*/
|
|
for (i = 0; i < MAXLISTEN; i++)
|
|
ListenSocket[i] = PGINVALID_SOCKET;
|
|
|
|
if (ListenAddresses)
|
|
{
|
|
char *rawstring;
|
|
List *elemlist;
|
|
ListCell *l;
|
|
int success = 0;
|
|
|
|
/* Need a modifiable copy of ListenAddresses */
|
|
rawstring = pstrdup(ListenAddresses);
|
|
|
|
/* Parse string into list of identifiers */
|
|
if (!SplitIdentifierString(rawstring, ',', &elemlist))
|
|
{
|
|
/* syntax error in list */
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
|
|
errmsg("invalid list syntax for \"listen_addresses\"")));
|
|
}
|
|
|
|
foreach(l, elemlist)
|
|
{
|
|
char *curhost = (char *) lfirst(l);
|
|
|
|
if (strcmp(curhost, "*") == 0)
|
|
status = StreamServerPort(AF_UNSPEC, NULL,
|
|
(unsigned short) PostPortNumber,
|
|
UnixSocketDir,
|
|
ListenSocket, MAXLISTEN);
|
|
else
|
|
status = StreamServerPort(AF_UNSPEC, curhost,
|
|
(unsigned short) PostPortNumber,
|
|
UnixSocketDir,
|
|
ListenSocket, MAXLISTEN);
|
|
if (status == STATUS_OK)
|
|
success++;
|
|
else
|
|
ereport(WARNING,
|
|
(errmsg("could not create listen socket for \"%s\"",
|
|
curhost)));
|
|
}
|
|
|
|
if (!success && list_length(elemlist))
|
|
ereport(FATAL,
|
|
(errmsg("could not create any TCP/IP sockets")));
|
|
|
|
list_free(elemlist);
|
|
pfree(rawstring);
|
|
}
|
|
|
|
#ifdef USE_BONJOUR
|
|
/* Register for Bonjour only if we opened TCP socket(s) */
|
|
if (enable_bonjour && ListenSocket[0] != PGINVALID_SOCKET)
|
|
{
|
|
DNSServiceErrorType err;
|
|
|
|
/*
|
|
* We pass 0 for interface_index, which will result in registering on
|
|
* all "applicable" interfaces. It's not entirely clear from the
|
|
* DNS-SD docs whether this would be appropriate if we have bound to
|
|
* just a subset of the available network interfaces.
|
|
*/
|
|
err = DNSServiceRegister(&bonjour_sdref,
|
|
0,
|
|
0,
|
|
bonjour_name,
|
|
"_postgresql._tcp.",
|
|
NULL,
|
|
NULL,
|
|
htons(PostPortNumber),
|
|
0,
|
|
NULL,
|
|
NULL,
|
|
NULL);
|
|
if (err != kDNSServiceErr_NoError)
|
|
elog(LOG, "DNSServiceRegister() failed: error code %ld",
|
|
(long) err);
|
|
|
|
/*
|
|
* We don't bother to read the mDNS daemon's reply, and we expect that
|
|
* it will automatically terminate our registration when the socket is
|
|
* closed at postmaster termination. So there's nothing more to be
|
|
* done here. However, the bonjour_sdref is kept around so that
|
|
* forked children can close their copies of the socket.
|
|
*/
|
|
}
|
|
#endif
|
|
|
|
#ifdef HAVE_UNIX_SOCKETS
|
|
status = StreamServerPort(AF_UNIX, NULL,
|
|
(unsigned short) PostPortNumber,
|
|
UnixSocketDir,
|
|
ListenSocket, MAXLISTEN);
|
|
if (status != STATUS_OK)
|
|
ereport(WARNING,
|
|
(errmsg("could not create Unix-domain socket")));
|
|
#endif
|
|
|
|
/*
|
|
* check that we have some socket to listen on
|
|
*/
|
|
if (ListenSocket[0] == PGINVALID_SOCKET)
|
|
ereport(FATAL,
|
|
(errmsg("no socket created for listening")));
|
|
|
|
/*
|
|
* Set up shared memory and semaphores.
|
|
*/
|
|
reset_shared(PostPortNumber);
|
|
|
|
/*
|
|
* Estimate number of openable files. This must happen after setting up
|
|
* semaphores, because on some platforms semaphores count as open files.
|
|
*/
|
|
set_max_safe_fds();
|
|
|
|
/*
|
|
* Initialize the list of active backends.
|
|
*/
|
|
BackendList = DLNewList();
|
|
|
|
#ifdef WIN32
|
|
|
|
/*
|
|
* Initialize I/O completion port used to deliver list of dead children.
|
|
*/
|
|
win32ChildQueue = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 1);
|
|
if (win32ChildQueue == NULL)
|
|
ereport(FATAL,
|
|
(errmsg("could not create I/O completion port for child queue")));
|
|
|
|
/*
|
|
* Set up a handle that child processes can use to check whether the
|
|
* postmaster is still running.
|
|
*/
|
|
if (DuplicateHandle(GetCurrentProcess(),
|
|
GetCurrentProcess(),
|
|
GetCurrentProcess(),
|
|
&PostmasterHandle,
|
|
0,
|
|
TRUE,
|
|
DUPLICATE_SAME_ACCESS) == 0)
|
|
ereport(FATAL,
|
|
(errmsg_internal("could not duplicate postmaster handle: error code %d",
|
|
(int) GetLastError())));
|
|
#endif
|
|
|
|
/*
|
|
* Record postmaster options. We delay this till now to avoid recording
|
|
* bogus options (eg, NBuffers too high for available memory).
|
|
*/
|
|
if (!CreateOptsFile(argc, argv, my_exec_path))
|
|
ExitPostmaster(1);
|
|
|
|
#ifdef EXEC_BACKEND
|
|
/* Write out nondefault GUC settings for child processes to use */
|
|
write_nondefault_variables(PGC_POSTMASTER);
|
|
#endif
|
|
|
|
/*
|
|
* Write the external PID file if requested
|
|
*/
|
|
if (external_pid_file)
|
|
{
|
|
FILE *fpidfile = fopen(external_pid_file, "w");
|
|
|
|
if (fpidfile)
|
|
{
|
|
fprintf(fpidfile, "%d\n", MyProcPid);
|
|
fclose(fpidfile);
|
|
/* Should we remove the pid file on postmaster exit? */
|
|
}
|
|
else
|
|
write_stderr("%s: could not write external PID file \"%s\": %s\n",
|
|
progname, external_pid_file, strerror(errno));
|
|
}
|
|
|
|
/*
|
|
* Set up signal handlers for the postmaster process.
|
|
*
|
|
* CAUTION: when changing this list, check for side-effects on the signal
|
|
* handling setup of child processes. See tcop/postgres.c,
|
|
* bootstrap/bootstrap.c, postmaster/bgwriter.c, postmaster/walwriter.c,
|
|
* postmaster/autovacuum.c, postmaster/pgarch.c, postmaster/pgstat.c, and
|
|
* postmaster/syslogger.c.
|
|
*/
|
|
pqinitmask();
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
pqsignal(SIGHUP, SIGHUP_handler); /* reread config file and have
|
|
* children do same */
|
|
pqsignal(SIGINT, pmdie); /* send SIGTERM and shut down */
|
|
pqsignal(SIGQUIT, pmdie); /* send SIGQUIT and die */
|
|
pqsignal(SIGTERM, pmdie); /* wait for children and shut down */
|
|
pqsignal(SIGALRM, SIG_IGN); /* ignored */
|
|
pqsignal(SIGPIPE, SIG_IGN); /* ignored */
|
|
pqsignal(SIGUSR1, sigusr1_handler); /* message from child process */
|
|
pqsignal(SIGUSR2, dummy_handler); /* unused, reserve for children */
|
|
pqsignal(SIGCHLD, reaper); /* handle child termination */
|
|
pqsignal(SIGTTIN, SIG_IGN); /* ignored */
|
|
pqsignal(SIGTTOU, SIG_IGN); /* ignored */
|
|
/* ignore SIGXFSZ, so that ulimit violations work like disk full */
|
|
#ifdef SIGXFSZ
|
|
pqsignal(SIGXFSZ, SIG_IGN); /* ignored */
|
|
#endif
|
|
|
|
/*
|
|
* If enabled, start up syslogger collection subprocess
|
|
*/
|
|
SysLoggerPID = SysLogger_Start();
|
|
|
|
/*
|
|
* Reset whereToSendOutput from DestDebug (its starting state) to
|
|
* DestNone. This stops ereport from sending log messages to stderr unless
|
|
* Log_destination permits. We don't do this until the postmaster is
|
|
* fully launched, since startup failures may as well be reported to
|
|
* stderr.
|
|
*/
|
|
whereToSendOutput = DestNone;
|
|
|
|
/*
|
|
* Initialize stats collection subsystem (this does NOT start the
|
|
* collector process!)
|
|
*/
|
|
pgstat_init();
|
|
|
|
/*
|
|
* Initialize the autovacuum subsystem (again, no process start yet)
|
|
*/
|
|
autovac_init();
|
|
|
|
/*
|
|
* Load configuration files for client authentication.
|
|
*/
|
|
if (!load_hba())
|
|
{
|
|
/*
|
|
* It makes no sense to continue if we fail to load the HBA file,
|
|
* since there is no way to connect to the database in this case.
|
|
*/
|
|
ereport(FATAL,
|
|
(errmsg("could not load pg_hba.conf")));
|
|
}
|
|
load_ident();
|
|
|
|
/*
|
|
* Remember postmaster startup time
|
|
*/
|
|
PgStartTime = GetCurrentTimestamp();
|
|
/* PostmasterRandom wants its own copy */
|
|
gettimeofday(&random_start_time, NULL);
|
|
|
|
/*
|
|
* We're ready to rock and roll...
|
|
*/
|
|
StartupPID = StartupDataBase();
|
|
Assert(StartupPID != 0);
|
|
pmState = PM_STARTUP;
|
|
|
|
status = ServerLoop();
|
|
|
|
/*
|
|
* ServerLoop probably shouldn't ever return, but if it does, close down.
|
|
*/
|
|
ExitPostmaster(status != STATUS_OK);
|
|
|
|
return 0; /* not reached */
|
|
}
|
|
|
|
|
|
/*
|
|
* Compute and check the directory paths to files that are part of the
|
|
* installation (as deduced from the postgres executable's own location)
|
|
*/
|
|
static void
|
|
getInstallationPaths(const char *argv0)
|
|
{
|
|
DIR *pdir;
|
|
|
|
/* Locate the postgres executable itself */
|
|
if (find_my_exec(argv0, my_exec_path) < 0)
|
|
elog(FATAL, "%s: could not locate my own executable path", argv0);
|
|
|
|
#ifdef EXEC_BACKEND
|
|
/* Locate executable backend before we change working directory */
|
|
if (find_other_exec(argv0, "postgres", PG_BACKEND_VERSIONSTR,
|
|
postgres_exec_path) < 0)
|
|
ereport(FATAL,
|
|
(errmsg("%s: could not locate matching postgres executable",
|
|
argv0)));
|
|
#endif
|
|
|
|
/*
|
|
* Locate the pkglib directory --- this has to be set early in case we try
|
|
* to load any modules from it in response to postgresql.conf entries.
|
|
*/
|
|
get_pkglib_path(my_exec_path, pkglib_path);
|
|
|
|
/*
|
|
* Verify that there's a readable directory there; otherwise the Postgres
|
|
* installation is incomplete or corrupt. (A typical cause of this
|
|
* failure is that the postgres executable has been moved or hardlinked to
|
|
* some directory that's not a sibling of the installation lib/
|
|
* directory.)
|
|
*/
|
|
pdir = AllocateDir(pkglib_path);
|
|
if (pdir == NULL)
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not open directory \"%s\": %m",
|
|
pkglib_path),
|
|
errhint("This may indicate an incomplete PostgreSQL installation, or that the file \"%s\" has been moved away from its proper location.",
|
|
my_exec_path)));
|
|
FreeDir(pdir);
|
|
|
|
/*
|
|
* XXX is it worth similarly checking the share/ directory? If the lib/
|
|
* directory is there, then share/ probably is too.
|
|
*/
|
|
}
|
|
|
|
|
|
/*
|
|
* Validate the proposed data directory
|
|
*/
|
|
static void
|
|
checkDataDir(void)
|
|
{
|
|
char path[MAXPGPATH];
|
|
FILE *fp;
|
|
struct stat stat_buf;
|
|
|
|
Assert(DataDir);
|
|
|
|
if (stat(DataDir, &stat_buf) != 0)
|
|
{
|
|
if (errno == ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("data directory \"%s\" does not exist",
|
|
DataDir)));
|
|
else
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read permissions of directory \"%s\": %m",
|
|
DataDir)));
|
|
}
|
|
|
|
/* eventual chdir would fail anyway, but let's test ... */
|
|
if (!S_ISDIR(stat_buf.st_mode))
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("specified data directory \"%s\" is not a directory",
|
|
DataDir)));
|
|
|
|
/*
|
|
* Check that the directory belongs to my userid; if not, reject.
|
|
*
|
|
* This check is an essential part of the interlock that prevents two
|
|
* postmasters from starting in the same directory (see CreateLockFile()).
|
|
* Do not remove or weaken it.
|
|
*
|
|
* XXX can we safely enable this check on Windows?
|
|
*/
|
|
#if !defined(WIN32) && !defined(__CYGWIN__)
|
|
if (stat_buf.st_uid != geteuid())
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("data directory \"%s\" has wrong ownership",
|
|
DataDir),
|
|
errhint("The server must be started by the user that owns the data directory.")));
|
|
#endif
|
|
|
|
/*
|
|
* Check if the directory has group or world access. If so, reject.
|
|
*
|
|
* It would be possible to allow weaker constraints (for example, allow
|
|
* group access) but we cannot make a general assumption that that is
|
|
* okay; for example there are platforms where nearly all users
|
|
* customarily belong to the same group. Perhaps this test should be
|
|
* configurable.
|
|
*
|
|
* XXX temporarily suppress check when on Windows, because there may not
|
|
* be proper support for Unix-y file permissions. Need to think of a
|
|
* reasonable check to apply on Windows.
|
|
*/
|
|
#if !defined(WIN32) && !defined(__CYGWIN__)
|
|
if (stat_buf.st_mode & (S_IRWXG | S_IRWXO))
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("data directory \"%s\" has group or world access",
|
|
DataDir),
|
|
errdetail("Permissions should be u=rwx (0700).")));
|
|
#endif
|
|
|
|
/* Look for PG_VERSION before looking for pg_control */
|
|
ValidatePgVersion(DataDir);
|
|
|
|
snprintf(path, sizeof(path), "%s/global/pg_control", DataDir);
|
|
|
|
fp = AllocateFile(path, PG_BINARY_R);
|
|
if (fp == NULL)
|
|
{
|
|
write_stderr("%s: could not find the database system\n"
|
|
"Expected to find it in the directory \"%s\",\n"
|
|
"but could not open file \"%s\": %s\n",
|
|
progname, DataDir, path, strerror(errno));
|
|
ExitPostmaster(2);
|
|
}
|
|
FreeFile(fp);
|
|
}
|
|
|
|
|
|
/*
|
|
* Fork away from the controlling terminal (silent_mode option)
|
|
*
|
|
* Since this requires disconnecting from stdin/stdout/stderr (in case they're
|
|
* linked to the terminal), we re-point stdin to /dev/null and stdout/stderr
|
|
* to "postmaster.log" in the data directory, where we're already chdir'd.
|
|
*/
|
|
static void
|
|
pmdaemonize(void)
|
|
{
|
|
#ifndef WIN32
|
|
const char *pmlogname = "postmaster.log";
|
|
int dvnull;
|
|
int pmlog;
|
|
pid_t pid;
|
|
int res;
|
|
|
|
/*
|
|
* Make sure we can open the files we're going to redirect to. If this
|
|
* fails, we want to complain before disconnecting. Mention the full path
|
|
* of the logfile in the error message, even though we address it by
|
|
* relative path.
|
|
*/
|
|
dvnull = open(DEVNULL, O_RDONLY, 0);
|
|
if (dvnull < 0)
|
|
{
|
|
write_stderr("%s: could not open file \"%s\": %s\n",
|
|
progname, DEVNULL, strerror(errno));
|
|
ExitPostmaster(1);
|
|
}
|
|
pmlog = open(pmlogname, O_CREAT | O_WRONLY | O_APPEND, 0600);
|
|
if (pmlog < 0)
|
|
{
|
|
write_stderr("%s: could not open log file \"%s/%s\": %s\n",
|
|
progname, DataDir, pmlogname, strerror(errno));
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
/*
|
|
* Okay to fork.
|
|
*/
|
|
pid = fork_process();
|
|
if (pid == (pid_t) -1)
|
|
{
|
|
write_stderr("%s: could not fork background process: %s\n",
|
|
progname, strerror(errno));
|
|
ExitPostmaster(1);
|
|
}
|
|
else if (pid)
|
|
{ /* parent */
|
|
/* Parent should just exit, without doing any atexit cleanup */
|
|
_exit(0);
|
|
}
|
|
|
|
MyProcPid = PostmasterPid = getpid(); /* reset PID vars to child */
|
|
|
|
MyStartTime = time(NULL);
|
|
|
|
/*
|
|
* Some systems use setsid() to dissociate from the TTY's process group,
|
|
* while on others it depends on stdin/stdout/stderr. Do both if
|
|
* possible.
|
|
*/
|
|
#ifdef HAVE_SETSID
|
|
if (setsid() < 0)
|
|
{
|
|
write_stderr("%s: could not dissociate from controlling TTY: %s\n",
|
|
progname, strerror(errno));
|
|
ExitPostmaster(1);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Reassociate stdin/stdout/stderr. fork_process() cleared any pending
|
|
* output, so this should be safe. The only plausible error is EINTR,
|
|
* which just means we should retry.
|
|
*/
|
|
do
|
|
{
|
|
res = dup2(dvnull, 0);
|
|
} while (res < 0 && errno == EINTR);
|
|
close(dvnull);
|
|
do
|
|
{
|
|
res = dup2(pmlog, 1);
|
|
} while (res < 0 && errno == EINTR);
|
|
do
|
|
{
|
|
res = dup2(pmlog, 2);
|
|
} while (res < 0 && errno == EINTR);
|
|
close(pmlog);
|
|
#else /* WIN32 */
|
|
/* not supported */
|
|
elog(FATAL, "silent_mode is not supported under Windows");
|
|
#endif /* WIN32 */
|
|
}
|
|
|
|
|
|
/*
|
|
* Main idle loop of postmaster
|
|
*/
|
|
static int
|
|
ServerLoop(void)
|
|
{
|
|
fd_set readmask;
|
|
int nSockets;
|
|
time_t now,
|
|
last_touch_time;
|
|
|
|
last_touch_time = time(NULL);
|
|
|
|
nSockets = initMasks(&readmask);
|
|
|
|
for (;;)
|
|
{
|
|
fd_set rmask;
|
|
int selres;
|
|
|
|
/*
|
|
* Wait for a connection request to arrive.
|
|
*
|
|
* We wait at most one minute, to ensure that the other background
|
|
* tasks handled below get done even when no requests are arriving.
|
|
*
|
|
* If we are in PM_WAIT_DEAD_END state, then we don't want to accept
|
|
* any new connections, so we don't call select() at all; just sleep
|
|
* for a little bit with signals unblocked.
|
|
*/
|
|
memcpy((char *) &rmask, (char *) &readmask, sizeof(fd_set));
|
|
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
if (pmState == PM_WAIT_DEAD_END)
|
|
{
|
|
pg_usleep(100000L); /* 100 msec seems reasonable */
|
|
selres = 0;
|
|
}
|
|
else
|
|
{
|
|
/* must set timeout each time; some OSes change it! */
|
|
struct timeval timeout;
|
|
|
|
timeout.tv_sec = 60;
|
|
timeout.tv_usec = 0;
|
|
|
|
selres = select(nSockets, &rmask, NULL, NULL, &timeout);
|
|
}
|
|
|
|
/*
|
|
* Block all signals until we wait again. (This makes it safe for our
|
|
* signal handlers to do nontrivial work.)
|
|
*/
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
/* Now check the select() result */
|
|
if (selres < 0)
|
|
{
|
|
if (errno != EINTR && errno != EWOULDBLOCK)
|
|
{
|
|
ereport(LOG,
|
|
(errcode_for_socket_access(),
|
|
errmsg("select() failed in postmaster: %m")));
|
|
return STATUS_ERROR;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* New connection pending on any of our sockets? If so, fork a child
|
|
* process to deal with it.
|
|
*/
|
|
if (selres > 0)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < MAXLISTEN; i++)
|
|
{
|
|
if (ListenSocket[i] == PGINVALID_SOCKET)
|
|
break;
|
|
if (FD_ISSET(ListenSocket[i], &rmask))
|
|
{
|
|
Port *port;
|
|
|
|
port = ConnCreate(ListenSocket[i]);
|
|
if (port)
|
|
{
|
|
BackendStartup(port);
|
|
|
|
/*
|
|
* We no longer need the open socket or port structure
|
|
* in this process
|
|
*/
|
|
StreamClose(port->sock);
|
|
ConnFree(port);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* If we have lost the log collector, try to start a new one */
|
|
if (SysLoggerPID == 0 && Logging_collector)
|
|
SysLoggerPID = SysLogger_Start();
|
|
|
|
/*
|
|
* If no background writer process is running, and we are not in a
|
|
* state that prevents it, start one. It doesn't matter if this
|
|
* fails, we'll just try again later.
|
|
*/
|
|
if (BgWriterPID == 0 &&
|
|
(pmState == PM_RUN || pmState == PM_RECOVERY ||
|
|
pmState == PM_RECOVERY_CONSISTENT))
|
|
BgWriterPID = StartBackgroundWriter();
|
|
|
|
/*
|
|
* Likewise, if we have lost the walwriter process, try to start a new
|
|
* one.
|
|
*/
|
|
if (WalWriterPID == 0 && pmState == PM_RUN)
|
|
WalWriterPID = StartWalWriter();
|
|
|
|
/* If we have lost the autovacuum launcher, try to start a new one */
|
|
if (AutoVacPID == 0 &&
|
|
(AutoVacuumingActive() || start_autovac_launcher) &&
|
|
pmState == PM_RUN)
|
|
{
|
|
AutoVacPID = StartAutoVacLauncher();
|
|
if (AutoVacPID != 0)
|
|
start_autovac_launcher = false; /* signal processed */
|
|
}
|
|
|
|
/* If we have lost the archiver, try to start a new one */
|
|
if (XLogArchivingActive() && PgArchPID == 0 && pmState == PM_RUN)
|
|
PgArchPID = pgarch_start();
|
|
|
|
/* If we have lost the stats collector, try to start a new one */
|
|
if (PgStatPID == 0 && pmState == PM_RUN)
|
|
PgStatPID = pgstat_start();
|
|
|
|
/* If we need to signal the autovacuum launcher, do so now */
|
|
if (avlauncher_needs_signal)
|
|
{
|
|
avlauncher_needs_signal = false;
|
|
if (AutoVacPID != 0)
|
|
kill(AutoVacPID, SIGUSR2);
|
|
}
|
|
|
|
/*
|
|
* Touch the socket and lock file every 58 minutes, to ensure that
|
|
* they are not removed by overzealous /tmp-cleaning tasks. We assume
|
|
* no one runs cleaners with cutoff times of less than an hour ...
|
|
*/
|
|
now = time(NULL);
|
|
if (now - last_touch_time >= 58 * SECS_PER_MINUTE)
|
|
{
|
|
TouchSocketFile();
|
|
TouchSocketLockFile();
|
|
last_touch_time = now;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Initialise the masks for select() for the ports we are listening on.
|
|
* Return the number of sockets to listen on.
|
|
*/
|
|
static int
|
|
initMasks(fd_set *rmask)
|
|
{
|
|
int maxsock = -1;
|
|
int i;
|
|
|
|
FD_ZERO(rmask);
|
|
|
|
for (i = 0; i < MAXLISTEN; i++)
|
|
{
|
|
int fd = ListenSocket[i];
|
|
|
|
if (fd == PGINVALID_SOCKET)
|
|
break;
|
|
FD_SET (fd, rmask);
|
|
|
|
if (fd > maxsock)
|
|
maxsock = fd;
|
|
}
|
|
|
|
return maxsock + 1;
|
|
}
|
|
|
|
|
|
/*
|
|
* Read a client's startup packet and do something according to it.
|
|
*
|
|
* Returns STATUS_OK or STATUS_ERROR, or might call ereport(FATAL) and
|
|
* not return at all.
|
|
*
|
|
* (Note that ereport(FATAL) stuff is sent to the client, so only use it
|
|
* if that's what you want. Return STATUS_ERROR if you don't want to
|
|
* send anything to the client, which would typically be appropriate
|
|
* if we detect a communications failure.)
|
|
*/
|
|
static int
|
|
ProcessStartupPacket(Port *port, bool SSLdone)
|
|
{
|
|
int32 len;
|
|
void *buf;
|
|
ProtocolVersion proto;
|
|
MemoryContext oldcontext;
|
|
|
|
if (pq_getbytes((char *) &len, 4) == EOF)
|
|
{
|
|
/*
|
|
* EOF after SSLdone probably means the client didn't like our
|
|
* response to NEGOTIATE_SSL_CODE. That's not an error condition, so
|
|
* don't clutter the log with a complaint.
|
|
*/
|
|
if (!SSLdone)
|
|
ereport(COMMERROR,
|
|
(errcode(ERRCODE_PROTOCOL_VIOLATION),
|
|
errmsg("incomplete startup packet")));
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
len = ntohl(len);
|
|
len -= 4;
|
|
|
|
if (len < (int32) sizeof(ProtocolVersion) ||
|
|
len > MAX_STARTUP_PACKET_LENGTH)
|
|
{
|
|
ereport(COMMERROR,
|
|
(errcode(ERRCODE_PROTOCOL_VIOLATION),
|
|
errmsg("invalid length of startup packet")));
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
/*
|
|
* Allocate at least the size of an old-style startup packet, plus one
|
|
* extra byte, and make sure all are zeroes. This ensures we will have
|
|
* null termination of all strings, in both fixed- and variable-length
|
|
* packet layouts.
|
|
*/
|
|
if (len <= (int32) sizeof(StartupPacket))
|
|
buf = palloc0(sizeof(StartupPacket) + 1);
|
|
else
|
|
buf = palloc0(len + 1);
|
|
|
|
if (pq_getbytes(buf, len) == EOF)
|
|
{
|
|
ereport(COMMERROR,
|
|
(errcode(ERRCODE_PROTOCOL_VIOLATION),
|
|
errmsg("incomplete startup packet")));
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
/*
|
|
* The first field is either a protocol version number or a special
|
|
* request code.
|
|
*/
|
|
port->proto = proto = ntohl(*((ProtocolVersion *) buf));
|
|
|
|
if (proto == CANCEL_REQUEST_CODE)
|
|
{
|
|
processCancelRequest(port, buf);
|
|
/* Not really an error, but we don't want to proceed further */
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
if (proto == NEGOTIATE_SSL_CODE && !SSLdone)
|
|
{
|
|
char SSLok;
|
|
|
|
#ifdef USE_SSL
|
|
/* No SSL when disabled or on Unix sockets */
|
|
if (!EnableSSL || IS_AF_UNIX(port->laddr.addr.ss_family))
|
|
SSLok = 'N';
|
|
else
|
|
SSLok = 'S'; /* Support for SSL */
|
|
#else
|
|
SSLok = 'N'; /* No support for SSL */
|
|
#endif
|
|
|
|
retry1:
|
|
if (send(port->sock, &SSLok, 1, 0) != 1)
|
|
{
|
|
if (errno == EINTR)
|
|
goto retry1; /* if interrupted, just retry */
|
|
ereport(COMMERROR,
|
|
(errcode_for_socket_access(),
|
|
errmsg("failed to send SSL negotiation response: %m")));
|
|
return STATUS_ERROR; /* close the connection */
|
|
}
|
|
|
|
#ifdef USE_SSL
|
|
if (SSLok == 'S' && secure_open_server(port) == -1)
|
|
return STATUS_ERROR;
|
|
#endif
|
|
/* regular startup packet, cancel, etc packet should follow... */
|
|
/* but not another SSL negotiation request */
|
|
return ProcessStartupPacket(port, true);
|
|
}
|
|
|
|
/* Could add additional special packet types here */
|
|
|
|
/*
|
|
* Set FrontendProtocol now so that ereport() knows what format to send if
|
|
* we fail during startup.
|
|
*/
|
|
FrontendProtocol = proto;
|
|
|
|
/* Check we can handle the protocol the frontend is using. */
|
|
|
|
if (PG_PROTOCOL_MAJOR(proto) < PG_PROTOCOL_MAJOR(PG_PROTOCOL_EARLIEST) ||
|
|
PG_PROTOCOL_MAJOR(proto) > PG_PROTOCOL_MAJOR(PG_PROTOCOL_LATEST) ||
|
|
(PG_PROTOCOL_MAJOR(proto) == PG_PROTOCOL_MAJOR(PG_PROTOCOL_LATEST) &&
|
|
PG_PROTOCOL_MINOR(proto) > PG_PROTOCOL_MINOR(PG_PROTOCOL_LATEST)))
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("unsupported frontend protocol %u.%u: server supports %u.0 to %u.%u",
|
|
PG_PROTOCOL_MAJOR(proto), PG_PROTOCOL_MINOR(proto),
|
|
PG_PROTOCOL_MAJOR(PG_PROTOCOL_EARLIEST),
|
|
PG_PROTOCOL_MAJOR(PG_PROTOCOL_LATEST),
|
|
PG_PROTOCOL_MINOR(PG_PROTOCOL_LATEST))));
|
|
|
|
/*
|
|
* Now fetch parameters out of startup packet and save them into the Port
|
|
* structure. All data structures attached to the Port struct must be
|
|
* allocated in TopMemoryContext so that they will remain available in a
|
|
* running backend (even after PostmasterContext is destroyed). We need
|
|
* not worry about leaking this storage on failure, since we aren't in the
|
|
* postmaster process anymore.
|
|
*/
|
|
oldcontext = MemoryContextSwitchTo(TopMemoryContext);
|
|
|
|
if (PG_PROTOCOL_MAJOR(proto) >= 3)
|
|
{
|
|
int32 offset = sizeof(ProtocolVersion);
|
|
|
|
/*
|
|
* Scan packet body for name/option pairs. We can assume any string
|
|
* beginning within the packet body is null-terminated, thanks to
|
|
* zeroing extra byte above.
|
|
*/
|
|
port->guc_options = NIL;
|
|
|
|
while (offset < len)
|
|
{
|
|
char *nameptr = ((char *) buf) + offset;
|
|
int32 valoffset;
|
|
char *valptr;
|
|
|
|
if (*nameptr == '\0')
|
|
break; /* found packet terminator */
|
|
valoffset = offset + strlen(nameptr) + 1;
|
|
if (valoffset >= len)
|
|
break; /* missing value, will complain below */
|
|
valptr = ((char *) buf) + valoffset;
|
|
|
|
if (strcmp(nameptr, "database") == 0)
|
|
port->database_name = pstrdup(valptr);
|
|
else if (strcmp(nameptr, "user") == 0)
|
|
port->user_name = pstrdup(valptr);
|
|
else if (strcmp(nameptr, "options") == 0)
|
|
port->cmdline_options = pstrdup(valptr);
|
|
else if (strcmp(nameptr, "replication") == 0)
|
|
{
|
|
if (!parse_bool(valptr, &am_walsender))
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
|
|
errmsg("invalid value for boolean option \"replication\"")));
|
|
}
|
|
else
|
|
{
|
|
/* Assume it's a generic GUC option */
|
|
port->guc_options = lappend(port->guc_options,
|
|
pstrdup(nameptr));
|
|
port->guc_options = lappend(port->guc_options,
|
|
pstrdup(valptr));
|
|
}
|
|
offset = valoffset + strlen(valptr) + 1;
|
|
}
|
|
|
|
/*
|
|
* If we didn't find a packet terminator exactly at the end of the
|
|
* given packet length, complain.
|
|
*/
|
|
if (offset != len - 1)
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_PROTOCOL_VIOLATION),
|
|
errmsg("invalid startup packet layout: expected terminator as last byte")));
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Get the parameters from the old-style, fixed-width-fields startup
|
|
* packet as C strings. The packet destination was cleared first so a
|
|
* short packet has zeros silently added. We have to be prepared to
|
|
* truncate the pstrdup result for oversize fields, though.
|
|
*/
|
|
StartupPacket *packet = (StartupPacket *) buf;
|
|
|
|
port->database_name = pstrdup(packet->database);
|
|
if (strlen(port->database_name) > sizeof(packet->database))
|
|
port->database_name[sizeof(packet->database)] = '\0';
|
|
port->user_name = pstrdup(packet->user);
|
|
if (strlen(port->user_name) > sizeof(packet->user))
|
|
port->user_name[sizeof(packet->user)] = '\0';
|
|
port->cmdline_options = pstrdup(packet->options);
|
|
if (strlen(port->cmdline_options) > sizeof(packet->options))
|
|
port->cmdline_options[sizeof(packet->options)] = '\0';
|
|
port->guc_options = NIL;
|
|
}
|
|
|
|
/* Check a user name was given. */
|
|
if (port->user_name == NULL || port->user_name[0] == '\0')
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
|
|
errmsg("no PostgreSQL user name specified in startup packet")));
|
|
|
|
/* The database defaults to the user name. */
|
|
if (port->database_name == NULL || port->database_name[0] == '\0')
|
|
port->database_name = pstrdup(port->user_name);
|
|
|
|
if (Db_user_namespace)
|
|
{
|
|
/*
|
|
* If user@, it is a global user, remove '@'. We only want to do this
|
|
* if there is an '@' at the end and no earlier in the user string or
|
|
* they may fake as a local user of another database attaching to this
|
|
* database.
|
|
*/
|
|
if (strchr(port->user_name, '@') ==
|
|
port->user_name + strlen(port->user_name) - 1)
|
|
*strchr(port->user_name, '@') = '\0';
|
|
else
|
|
{
|
|
/* Append '@' and dbname */
|
|
char *db_user;
|
|
|
|
db_user = palloc(strlen(port->user_name) +
|
|
strlen(port->database_name) + 2);
|
|
sprintf(db_user, "%s@%s", port->user_name, port->database_name);
|
|
port->user_name = db_user;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Truncate given database and user names to length of a Postgres name.
|
|
* This avoids lookup failures when overlength names are given.
|
|
*/
|
|
if (strlen(port->database_name) >= NAMEDATALEN)
|
|
port->database_name[NAMEDATALEN - 1] = '\0';
|
|
if (strlen(port->user_name) >= NAMEDATALEN)
|
|
port->user_name[NAMEDATALEN - 1] = '\0';
|
|
|
|
/* Walsender is not related to a particular database */
|
|
if (am_walsender)
|
|
port->database_name[0] = '\0';
|
|
|
|
/*
|
|
* Done putting stuff in TopMemoryContext.
|
|
*/
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/*
|
|
* If we're going to reject the connection due to database state, say so
|
|
* now instead of wasting cycles on an authentication exchange. (This also
|
|
* allows a pg_ping utility to be written.)
|
|
*/
|
|
switch (port->canAcceptConnections)
|
|
{
|
|
case CAC_STARTUP:
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_CANNOT_CONNECT_NOW),
|
|
errmsg("the database system is starting up")));
|
|
break;
|
|
case CAC_SHUTDOWN:
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_CANNOT_CONNECT_NOW),
|
|
errmsg("the database system is shutting down")));
|
|
break;
|
|
case CAC_RECOVERY:
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_CANNOT_CONNECT_NOW),
|
|
errmsg("the database system is in recovery mode")));
|
|
break;
|
|
case CAC_TOOMANY:
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_TOO_MANY_CONNECTIONS),
|
|
errmsg("sorry, too many clients already")));
|
|
break;
|
|
case CAC_WAITBACKUP:
|
|
/* OK for now, will check in InitPostgres */
|
|
break;
|
|
case CAC_OK:
|
|
break;
|
|
}
|
|
|
|
return STATUS_OK;
|
|
}
|
|
|
|
|
|
/*
|
|
* The client has sent a cancel request packet, not a normal
|
|
* start-a-new-connection packet. Perform the necessary processing.
|
|
* Nothing is sent back to the client.
|
|
*/
|
|
static void
|
|
processCancelRequest(Port *port, void *pkt)
|
|
{
|
|
CancelRequestPacket *canc = (CancelRequestPacket *) pkt;
|
|
int backendPID;
|
|
long cancelAuthCode;
|
|
Backend *bp;
|
|
|
|
#ifndef EXEC_BACKEND
|
|
Dlelem *curr;
|
|
#else
|
|
int i;
|
|
#endif
|
|
|
|
backendPID = (int) ntohl(canc->backendPID);
|
|
cancelAuthCode = (long) ntohl(canc->cancelAuthCode);
|
|
|
|
/*
|
|
* See if we have a matching backend. In the EXEC_BACKEND case, we can no
|
|
* longer access the postmaster's own backend list, and must rely on the
|
|
* duplicate array in shared memory.
|
|
*/
|
|
#ifndef EXEC_BACKEND
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
bp = (Backend *) DLE_VAL(curr);
|
|
#else
|
|
for (i = MaxLivePostmasterChildren() - 1; i >= 0; i--)
|
|
{
|
|
bp = (Backend *) &ShmemBackendArray[i];
|
|
#endif
|
|
if (bp->pid == backendPID)
|
|
{
|
|
if (bp->cancel_key == cancelAuthCode)
|
|
{
|
|
/* Found a match; signal that backend to cancel current op */
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("processing cancel request: sending SIGINT to process %d",
|
|
backendPID)));
|
|
signal_child(bp->pid, SIGINT);
|
|
}
|
|
else
|
|
/* Right PID, wrong key: no way, Jose */
|
|
ereport(LOG,
|
|
(errmsg("wrong key in cancel request for process %d",
|
|
backendPID)));
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* No matching backend */
|
|
ereport(LOG,
|
|
(errmsg("PID %d in cancel request did not match any process",
|
|
backendPID)));
|
|
}
|
|
|
|
/*
|
|
* canAcceptConnections --- check to see if database state allows connections.
|
|
*/
|
|
static enum CAC_state
|
|
canAcceptConnections(void)
|
|
{
|
|
/*
|
|
* Can't start backends when in startup/shutdown/inconsistent recovery
|
|
* state.
|
|
*
|
|
* In state PM_WAIT_BACKUP only superusers can connect (this must be
|
|
* allowed so that a superuser can end online backup mode); we return
|
|
* CAC_WAITBACKUP code to indicate that this must be checked later.
|
|
*/
|
|
if (pmState != PM_RUN)
|
|
{
|
|
if (pmState == PM_WAIT_BACKUP)
|
|
return CAC_WAITBACKUP; /* allow superusers only */
|
|
if (Shutdown > NoShutdown)
|
|
return CAC_SHUTDOWN; /* shutdown is pending */
|
|
if (!FatalError &&
|
|
(pmState == PM_STARTUP ||
|
|
pmState == PM_RECOVERY))
|
|
return CAC_STARTUP; /* normal startup */
|
|
if (!FatalError &&
|
|
pmState == PM_RECOVERY_CONSISTENT)
|
|
return CAC_OK; /* connection OK during recovery */
|
|
return CAC_RECOVERY; /* else must be crash recovery */
|
|
}
|
|
|
|
/*
|
|
* Don't start too many children.
|
|
*
|
|
* We allow more connections than we can have backends here because some
|
|
* might still be authenticating; they might fail auth, or some existing
|
|
* backend might exit before the auth cycle is completed. The exact
|
|
* MaxBackends limit is enforced when a new backend tries to join the
|
|
* shared-inval backend array.
|
|
*
|
|
* The limit here must match the sizes of the per-child-process arrays;
|
|
* see comments for MaxLivePostmasterChildren().
|
|
*/
|
|
if (CountChildren(BACKEND_TYPE_ALL) >= MaxLivePostmasterChildren())
|
|
return CAC_TOOMANY;
|
|
|
|
return CAC_OK;
|
|
}
|
|
|
|
|
|
/*
|
|
* ConnCreate -- create a local connection data structure
|
|
*/
|
|
static Port *
|
|
ConnCreate(int serverFd)
|
|
{
|
|
Port *port;
|
|
|
|
if (!(port = (Port *) calloc(1, sizeof(Port))))
|
|
{
|
|
ereport(LOG,
|
|
(errcode(ERRCODE_OUT_OF_MEMORY),
|
|
errmsg("out of memory")));
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
if (StreamConnection(serverFd, port) != STATUS_OK)
|
|
{
|
|
if (port->sock >= 0)
|
|
StreamClose(port->sock);
|
|
ConnFree(port);
|
|
port = NULL;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Precompute password salt values to use for this connection. It's
|
|
* slightly annoying to do this long in advance of knowing whether
|
|
* we'll need 'em or not, but we must do the random() calls before we
|
|
* fork, not after. Else the postmaster's random sequence won't get
|
|
* advanced, and all backends would end up using the same salt...
|
|
*/
|
|
RandomSalt(port->md5Salt);
|
|
}
|
|
|
|
/*
|
|
* Allocate GSSAPI specific state struct
|
|
*/
|
|
#ifndef EXEC_BACKEND
|
|
#if defined(ENABLE_GSS) || defined(ENABLE_SSPI)
|
|
port->gss = (pg_gssinfo *) calloc(1, sizeof(pg_gssinfo));
|
|
if (!port->gss)
|
|
{
|
|
ereport(LOG,
|
|
(errcode(ERRCODE_OUT_OF_MEMORY),
|
|
errmsg("out of memory")));
|
|
ExitPostmaster(1);
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
return port;
|
|
}
|
|
|
|
|
|
/*
|
|
* ConnFree -- free a local connection data structure
|
|
*/
|
|
static void
|
|
ConnFree(Port *conn)
|
|
{
|
|
#ifdef USE_SSL
|
|
secure_close(conn);
|
|
#endif
|
|
if (conn->gss)
|
|
free(conn->gss);
|
|
free(conn);
|
|
}
|
|
|
|
|
|
/*
|
|
* ClosePostmasterPorts -- close all the postmaster's open sockets
|
|
*
|
|
* This is called during child process startup to release file descriptors
|
|
* that are not needed by that child process. The postmaster still has
|
|
* them open, of course.
|
|
*
|
|
* Note: we pass am_syslogger as a boolean because we don't want to set
|
|
* the global variable yet when this is called.
|
|
*/
|
|
void
|
|
ClosePostmasterPorts(bool am_syslogger)
|
|
{
|
|
int i;
|
|
|
|
/* Close the listen sockets */
|
|
for (i = 0; i < MAXLISTEN; i++)
|
|
{
|
|
if (ListenSocket[i] != PGINVALID_SOCKET)
|
|
{
|
|
StreamClose(ListenSocket[i]);
|
|
ListenSocket[i] = PGINVALID_SOCKET;
|
|
}
|
|
}
|
|
|
|
/* If using syslogger, close the read side of the pipe */
|
|
if (!am_syslogger)
|
|
{
|
|
#ifndef WIN32
|
|
if (syslogPipe[0] >= 0)
|
|
close(syslogPipe[0]);
|
|
syslogPipe[0] = -1;
|
|
#else
|
|
if (syslogPipe[0])
|
|
CloseHandle(syslogPipe[0]);
|
|
syslogPipe[0] = 0;
|
|
#endif
|
|
}
|
|
|
|
#ifdef USE_BONJOUR
|
|
/* If using Bonjour, close the connection to the mDNS daemon */
|
|
if (bonjour_sdref)
|
|
close(DNSServiceRefSockFD(bonjour_sdref));
|
|
#endif
|
|
}
|
|
|
|
|
|
/*
|
|
* reset_shared -- reset shared memory and semaphores
|
|
*/
|
|
static void
|
|
reset_shared(int port)
|
|
{
|
|
/*
|
|
* Create or re-create shared memory and semaphores.
|
|
*
|
|
* Note: in each "cycle of life" we will normally assign the same IPC keys
|
|
* (if using SysV shmem and/or semas), since the port number is used to
|
|
* determine IPC keys. This helps ensure that we will clean up dead IPC
|
|
* objects if the postmaster crashes and is restarted.
|
|
*/
|
|
CreateSharedMemoryAndSemaphores(false, port);
|
|
}
|
|
|
|
|
|
/*
|
|
* SIGHUP -- reread config files, and tell children to do same
|
|
*/
|
|
static void
|
|
SIGHUP_handler(SIGNAL_ARGS)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
if (Shutdown <= SmartShutdown)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("received SIGHUP, reloading configuration files")));
|
|
ProcessConfigFile(PGC_SIGHUP);
|
|
SignalChildren(SIGHUP);
|
|
if (StartupPID != 0)
|
|
signal_child(StartupPID, SIGHUP);
|
|
if (BgWriterPID != 0)
|
|
signal_child(BgWriterPID, SIGHUP);
|
|
if (WalWriterPID != 0)
|
|
signal_child(WalWriterPID, SIGHUP);
|
|
if (WalReceiverPID != 0)
|
|
signal_child(WalReceiverPID, SIGHUP);
|
|
if (AutoVacPID != 0)
|
|
signal_child(AutoVacPID, SIGHUP);
|
|
if (PgArchPID != 0)
|
|
signal_child(PgArchPID, SIGHUP);
|
|
if (SysLoggerPID != 0)
|
|
signal_child(SysLoggerPID, SIGHUP);
|
|
if (PgStatPID != 0)
|
|
signal_child(PgStatPID, SIGHUP);
|
|
|
|
/* Reload authentication config files too */
|
|
if (!load_hba())
|
|
ereport(WARNING,
|
|
(errmsg("pg_hba.conf not reloaded")));
|
|
|
|
load_ident();
|
|
|
|
#ifdef EXEC_BACKEND
|
|
/* Update the starting-point file for future children */
|
|
write_nondefault_variables(PGC_SIGHUP);
|
|
#endif
|
|
}
|
|
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
|
|
/*
|
|
* pmdie -- signal handler for processing various postmaster signals.
|
|
*/
|
|
static void
|
|
pmdie(SIGNAL_ARGS)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("postmaster received signal %d",
|
|
postgres_signal_arg)));
|
|
|
|
switch (postgres_signal_arg)
|
|
{
|
|
case SIGTERM:
|
|
|
|
/*
|
|
* Smart Shutdown:
|
|
*
|
|
* Wait for children to end their work, then shut down.
|
|
*/
|
|
if (Shutdown >= SmartShutdown)
|
|
break;
|
|
Shutdown = SmartShutdown;
|
|
ereport(LOG,
|
|
(errmsg("received smart shutdown request")));
|
|
|
|
if (pmState == PM_RUN || pmState == PM_RECOVERY ||
|
|
pmState == PM_RECOVERY_CONSISTENT)
|
|
{
|
|
/* autovacuum workers are told to shut down immediately */
|
|
SignalAutovacWorkers(SIGTERM);
|
|
/* and the autovac launcher too */
|
|
if (AutoVacPID != 0)
|
|
signal_child(AutoVacPID, SIGTERM);
|
|
/* and the walwriter too */
|
|
if (WalWriterPID != 0)
|
|
signal_child(WalWriterPID, SIGTERM);
|
|
/*
|
|
* If we're in recovery, we can't kill the startup process
|
|
* right away, because at present doing so does not release
|
|
* its locks. We might want to change this in a future
|
|
* release. For the time being, the PM_WAIT_READONLY state
|
|
* indicates that we're waiting for the regular (read only)
|
|
* backends to die off; once they do, we'll kill the startup
|
|
* and walreceiver processes.
|
|
*/
|
|
pmState = (pmState == PM_RUN) ?
|
|
PM_WAIT_BACKUP : PM_WAIT_READONLY;
|
|
}
|
|
|
|
/*
|
|
* Now wait for online backup mode to end and backends to exit. If
|
|
* that is already the case, PostmasterStateMachine will take the
|
|
* next step.
|
|
*/
|
|
PostmasterStateMachine();
|
|
break;
|
|
|
|
case SIGINT:
|
|
|
|
/*
|
|
* Fast Shutdown:
|
|
*
|
|
* Abort all children with SIGTERM (rollback active transactions
|
|
* and exit) and shut down when they are gone.
|
|
*/
|
|
if (Shutdown >= FastShutdown)
|
|
break;
|
|
Shutdown = FastShutdown;
|
|
ereport(LOG,
|
|
(errmsg("received fast shutdown request")));
|
|
|
|
if (StartupPID != 0)
|
|
signal_child(StartupPID, SIGTERM);
|
|
if (WalReceiverPID != 0)
|
|
signal_child(WalReceiverPID, SIGTERM);
|
|
if (pmState == PM_RECOVERY)
|
|
{
|
|
/* only bgwriter is active in this state */
|
|
pmState = PM_WAIT_BACKENDS;
|
|
}
|
|
if (pmState == PM_RUN ||
|
|
pmState == PM_WAIT_BACKUP ||
|
|
pmState == PM_WAIT_READONLY ||
|
|
pmState == PM_WAIT_BACKENDS ||
|
|
pmState == PM_RECOVERY_CONSISTENT)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("aborting any active transactions")));
|
|
/* shut down all backends and autovac workers */
|
|
SignalSomeChildren(SIGTERM,
|
|
BACKEND_TYPE_NORMAL | BACKEND_TYPE_AUTOVAC);
|
|
/* and the autovac launcher too */
|
|
if (AutoVacPID != 0)
|
|
signal_child(AutoVacPID, SIGTERM);
|
|
/* and the walwriter too */
|
|
if (WalWriterPID != 0)
|
|
signal_child(WalWriterPID, SIGTERM);
|
|
pmState = PM_WAIT_BACKENDS;
|
|
}
|
|
|
|
/*
|
|
* Now wait for backends to exit. If there are none,
|
|
* PostmasterStateMachine will take the next step.
|
|
*/
|
|
PostmasterStateMachine();
|
|
break;
|
|
|
|
case SIGQUIT:
|
|
|
|
/*
|
|
* Immediate Shutdown:
|
|
*
|
|
* abort all children with SIGQUIT and exit without attempt to
|
|
* properly shut down data base system.
|
|
*/
|
|
ereport(LOG,
|
|
(errmsg("received immediate shutdown request")));
|
|
SignalChildren(SIGQUIT);
|
|
if (StartupPID != 0)
|
|
signal_child(StartupPID, SIGQUIT);
|
|
if (BgWriterPID != 0)
|
|
signal_child(BgWriterPID, SIGQUIT);
|
|
if (WalWriterPID != 0)
|
|
signal_child(WalWriterPID, SIGQUIT);
|
|
if (WalReceiverPID != 0)
|
|
signal_child(WalReceiverPID, SIGQUIT);
|
|
if (AutoVacPID != 0)
|
|
signal_child(AutoVacPID, SIGQUIT);
|
|
if (PgArchPID != 0)
|
|
signal_child(PgArchPID, SIGQUIT);
|
|
if (PgStatPID != 0)
|
|
signal_child(PgStatPID, SIGQUIT);
|
|
ExitPostmaster(0);
|
|
break;
|
|
}
|
|
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
/*
|
|
* Reaper -- signal handler to cleanup after a child process dies.
|
|
*/
|
|
static void
|
|
reaper(SIGNAL_ARGS)
|
|
{
|
|
int save_errno = errno;
|
|
int pid; /* process id of dead child process */
|
|
int exitstatus; /* its exit status */
|
|
|
|
/* These macros hide platform variations in getting child status */
|
|
#ifdef HAVE_WAITPID
|
|
int status; /* child exit status */
|
|
|
|
#define LOOPTEST() ((pid = waitpid(-1, &status, WNOHANG)) > 0)
|
|
#define LOOPHEADER() (exitstatus = status)
|
|
#else /* !HAVE_WAITPID */
|
|
#ifndef WIN32
|
|
union wait status; /* child exit status */
|
|
|
|
#define LOOPTEST() ((pid = wait3(&status, WNOHANG, NULL)) > 0)
|
|
#define LOOPHEADER() (exitstatus = status.w_status)
|
|
#else /* WIN32 */
|
|
#define LOOPTEST() ((pid = win32_waitpid(&exitstatus)) > 0)
|
|
#define LOOPHEADER()
|
|
#endif /* WIN32 */
|
|
#endif /* HAVE_WAITPID */
|
|
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
ereport(DEBUG4,
|
|
(errmsg_internal("reaping dead processes")));
|
|
|
|
while (LOOPTEST())
|
|
{
|
|
LOOPHEADER();
|
|
|
|
/*
|
|
* Check if this child was a startup process.
|
|
*/
|
|
if (pid == StartupPID)
|
|
{
|
|
StartupPID = 0;
|
|
|
|
/*
|
|
* Unexpected exit of startup process (including FATAL exit)
|
|
* during PM_STARTUP is treated as catastrophic. There are no
|
|
* other processes running yet, so we can just exit.
|
|
*/
|
|
if (pmState == PM_STARTUP && !EXIT_STATUS_0(exitstatus))
|
|
{
|
|
LogChildExit(LOG, _("startup process"),
|
|
pid, exitstatus);
|
|
ereport(LOG,
|
|
(errmsg("aborting startup due to startup process failure")));
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
/*
|
|
* Startup process exited in response to a shutdown request (or it
|
|
* completed normally regardless of the shutdown request).
|
|
*/
|
|
if (Shutdown > NoShutdown &&
|
|
(EXIT_STATUS_0(exitstatus) || EXIT_STATUS_1(exitstatus)))
|
|
{
|
|
pmState = PM_WAIT_BACKENDS;
|
|
/* PostmasterStateMachine logic does the rest */
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Any unexpected exit (including FATAL exit) of the startup
|
|
* process is treated as a crash, except that we don't want to
|
|
* reinitialize.
|
|
*/
|
|
if (!EXIT_STATUS_0(exitstatus))
|
|
{
|
|
RecoveryError = true;
|
|
HandleChildCrash(pid, exitstatus,
|
|
_("startup process"));
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Startup succeeded, commence normal operations
|
|
*/
|
|
FatalError = false;
|
|
pmState = PM_RUN;
|
|
|
|
/*
|
|
* Crank up the background writer, if we didn't do that already
|
|
* when we entered consistent recovery state. It doesn't matter
|
|
* if this fails, we'll just try again later.
|
|
*/
|
|
if (BgWriterPID == 0)
|
|
BgWriterPID = StartBackgroundWriter();
|
|
|
|
/*
|
|
* Likewise, start other special children as needed. In a restart
|
|
* situation, some of them may be alive already.
|
|
*/
|
|
if (WalWriterPID == 0)
|
|
WalWriterPID = StartWalWriter();
|
|
if (AutoVacuumingActive() && AutoVacPID == 0)
|
|
AutoVacPID = StartAutoVacLauncher();
|
|
if (XLogArchivingActive() && PgArchPID == 0)
|
|
PgArchPID = pgarch_start();
|
|
if (PgStatPID == 0)
|
|
PgStatPID = pgstat_start();
|
|
|
|
/* at this point we are really open for business */
|
|
ereport(LOG,
|
|
(errmsg("database system is ready to accept connections")));
|
|
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Was it the bgwriter?
|
|
*/
|
|
if (pid == BgWriterPID)
|
|
{
|
|
BgWriterPID = 0;
|
|
if (EXIT_STATUS_0(exitstatus) && pmState == PM_SHUTDOWN)
|
|
{
|
|
/*
|
|
* OK, we saw normal exit of the bgwriter after it's been told
|
|
* to shut down. We expect that it wrote a shutdown
|
|
* checkpoint. (If for some reason it didn't, recovery will
|
|
* occur on next postmaster start.)
|
|
*
|
|
* At this point we should have no normal backend children
|
|
* left (else we'd not be in PM_SHUTDOWN state) but we might
|
|
* have dead_end children to wait for.
|
|
*
|
|
* If we have an archiver subprocess, tell it to do a last
|
|
* archive cycle and quit. Likewise, if we have walsender
|
|
* processes, tell them to send any remaining WAL and quit.
|
|
*/
|
|
Assert(Shutdown > NoShutdown);
|
|
|
|
/* Waken archiver for the last time */
|
|
if (PgArchPID != 0)
|
|
signal_child(PgArchPID, SIGUSR2);
|
|
|
|
/*
|
|
* Waken walsenders for the last time. No regular backends
|
|
* should be around anymore.
|
|
*/
|
|
SignalChildren(SIGUSR2);
|
|
|
|
pmState = PM_SHUTDOWN_2;
|
|
|
|
/*
|
|
* We can also shut down the stats collector now; there's
|
|
* nothing left for it to do.
|
|
*/
|
|
if (PgStatPID != 0)
|
|
signal_child(PgStatPID, SIGQUIT);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Any unexpected exit of the bgwriter (including FATAL exit)
|
|
* is treated as a crash.
|
|
*/
|
|
HandleChildCrash(pid, exitstatus,
|
|
_("background writer process"));
|
|
}
|
|
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Was it the wal writer? Normal exit can be ignored; we'll start a
|
|
* new one at the next iteration of the postmaster's main loop, if
|
|
* necessary. Any other exit condition is treated as a crash.
|
|
*/
|
|
if (pid == WalWriterPID)
|
|
{
|
|
WalWriterPID = 0;
|
|
if (!EXIT_STATUS_0(exitstatus))
|
|
HandleChildCrash(pid, exitstatus,
|
|
_("WAL writer process"));
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Was it the wal receiver? If exit status is zero (normal) or one
|
|
* (FATAL exit), we assume everything is all right just like normal
|
|
* backends.
|
|
*/
|
|
if (pid == WalReceiverPID)
|
|
{
|
|
WalReceiverPID = 0;
|
|
if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
|
|
HandleChildCrash(pid, exitstatus,
|
|
_("WAL receiver process"));
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Was it the autovacuum launcher? Normal exit can be ignored; we'll
|
|
* start a new one at the next iteration of the postmaster's main
|
|
* loop, if necessary. Any other exit condition is treated as a
|
|
* crash.
|
|
*/
|
|
if (pid == AutoVacPID)
|
|
{
|
|
AutoVacPID = 0;
|
|
if (!EXIT_STATUS_0(exitstatus))
|
|
HandleChildCrash(pid, exitstatus,
|
|
_("autovacuum launcher process"));
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Was it the archiver? If so, just try to start a new one; no need
|
|
* to force reset of the rest of the system. (If fail, we'll try
|
|
* again in future cycles of the main loop.). Unless we were waiting
|
|
* for it to shut down; don't restart it in that case, and and
|
|
* PostmasterStateMachine() will advance to the next shutdown step.
|
|
*/
|
|
if (pid == PgArchPID)
|
|
{
|
|
PgArchPID = 0;
|
|
if (!EXIT_STATUS_0(exitstatus))
|
|
LogChildExit(LOG, _("archiver process"),
|
|
pid, exitstatus);
|
|
if (XLogArchivingActive() && pmState == PM_RUN)
|
|
PgArchPID = pgarch_start();
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Was it the statistics collector? If so, just try to start a new
|
|
* one; no need to force reset of the rest of the system. (If fail,
|
|
* we'll try again in future cycles of the main loop.)
|
|
*/
|
|
if (pid == PgStatPID)
|
|
{
|
|
PgStatPID = 0;
|
|
if (!EXIT_STATUS_0(exitstatus))
|
|
LogChildExit(LOG, _("statistics collector process"),
|
|
pid, exitstatus);
|
|
if (pmState == PM_RUN)
|
|
PgStatPID = pgstat_start();
|
|
continue;
|
|
}
|
|
|
|
/* Was it the system logger? If so, try to start a new one */
|
|
if (pid == SysLoggerPID)
|
|
{
|
|
SysLoggerPID = 0;
|
|
/* for safety's sake, launch new logger *first* */
|
|
SysLoggerPID = SysLogger_Start();
|
|
if (!EXIT_STATUS_0(exitstatus))
|
|
LogChildExit(LOG, _("system logger process"),
|
|
pid, exitstatus);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Else do standard backend child cleanup.
|
|
*/
|
|
CleanupBackend(pid, exitstatus);
|
|
} /* loop over pending child-death reports */
|
|
|
|
/*
|
|
* After cleaning out the SIGCHLD queue, see if we have any state changes
|
|
* or actions to make.
|
|
*/
|
|
PostmasterStateMachine();
|
|
|
|
/* Done with signal handler */
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
|
|
/*
|
|
* CleanupBackend -- cleanup after terminated backend.
|
|
*
|
|
* Remove all local state associated with backend.
|
|
*/
|
|
static void
|
|
CleanupBackend(int pid,
|
|
int exitstatus) /* child's exit status. */
|
|
{
|
|
Dlelem *curr;
|
|
|
|
LogChildExit(DEBUG2, _("server process"), pid, exitstatus);
|
|
|
|
/*
|
|
* If a backend dies in an ugly way then we must signal all other backends
|
|
* to quickdie. If exit status is zero (normal) or one (FATAL exit), we
|
|
* assume everything is all right and proceed to remove the backend from
|
|
* the active backend list.
|
|
*/
|
|
if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
|
|
{
|
|
HandleChildCrash(pid, exitstatus, _("server process"));
|
|
return;
|
|
}
|
|
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
Backend *bp = (Backend *) DLE_VAL(curr);
|
|
|
|
if (bp->pid == pid)
|
|
{
|
|
if (!bp->dead_end)
|
|
{
|
|
if (!ReleasePostmasterChildSlot(bp->child_slot))
|
|
{
|
|
/*
|
|
* Uh-oh, the child failed to clean itself up. Treat as a
|
|
* crash after all.
|
|
*/
|
|
HandleChildCrash(pid, exitstatus, _("server process"));
|
|
return;
|
|
}
|
|
#ifdef EXEC_BACKEND
|
|
ShmemBackendArrayRemove(bp);
|
|
#endif
|
|
}
|
|
DLRemove(curr);
|
|
free(bp);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* HandleChildCrash -- cleanup after failed backend, bgwriter, walwriter,
|
|
* or autovacuum.
|
|
*
|
|
* The objectives here are to clean up our local state about the child
|
|
* process, and to signal all other remaining children to quickdie.
|
|
*/
|
|
static void
|
|
HandleChildCrash(int pid, int exitstatus, const char *procname)
|
|
{
|
|
Dlelem *curr,
|
|
*next;
|
|
Backend *bp;
|
|
|
|
/*
|
|
* Make log entry unless there was a previous crash (if so, nonzero exit
|
|
* status is to be expected in SIGQUIT response; don't clutter log)
|
|
*/
|
|
if (!FatalError)
|
|
{
|
|
LogChildExit(LOG, procname, pid, exitstatus);
|
|
ereport(LOG,
|
|
(errmsg("terminating any other active server processes")));
|
|
}
|
|
|
|
/* Process regular backends */
|
|
for (curr = DLGetHead(BackendList); curr; curr = next)
|
|
{
|
|
next = DLGetSucc(curr);
|
|
bp = (Backend *) DLE_VAL(curr);
|
|
if (bp->pid == pid)
|
|
{
|
|
/*
|
|
* Found entry for freshly-dead backend, so remove it.
|
|
*/
|
|
if (!bp->dead_end)
|
|
{
|
|
(void) ReleasePostmasterChildSlot(bp->child_slot);
|
|
#ifdef EXEC_BACKEND
|
|
ShmemBackendArrayRemove(bp);
|
|
#endif
|
|
}
|
|
DLRemove(curr);
|
|
free(bp);
|
|
/* Keep looping so we can signal remaining backends */
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* This backend is still alive. Unless we did so already, tell it
|
|
* to commit hara-kiri.
|
|
*
|
|
* SIGQUIT is the special signal that says exit without proc_exit
|
|
* and let the user know what's going on. But if SendStop is set
|
|
* (-s on command line), then we send SIGSTOP instead, so that we
|
|
* can get core dumps from all backends by hand.
|
|
*
|
|
* We could exclude dead_end children here, but at least in the
|
|
* SIGSTOP case it seems better to include them.
|
|
*/
|
|
if (!FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
(SendStop ? "SIGSTOP" : "SIGQUIT"),
|
|
(int) bp->pid)));
|
|
signal_child(bp->pid, (SendStop ? SIGSTOP : SIGQUIT));
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Take care of the startup process too */
|
|
if (pid == StartupPID)
|
|
StartupPID = 0;
|
|
else if (StartupPID != 0 && !FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
(SendStop ? "SIGSTOP" : "SIGQUIT"),
|
|
(int) StartupPID)));
|
|
signal_child(StartupPID, (SendStop ? SIGSTOP : SIGQUIT));
|
|
}
|
|
|
|
/* Take care of the bgwriter too */
|
|
if (pid == BgWriterPID)
|
|
BgWriterPID = 0;
|
|
else if (BgWriterPID != 0 && !FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
(SendStop ? "SIGSTOP" : "SIGQUIT"),
|
|
(int) BgWriterPID)));
|
|
signal_child(BgWriterPID, (SendStop ? SIGSTOP : SIGQUIT));
|
|
}
|
|
|
|
/* Take care of the walwriter too */
|
|
if (pid == WalWriterPID)
|
|
WalWriterPID = 0;
|
|
else if (WalWriterPID != 0 && !FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
(SendStop ? "SIGSTOP" : "SIGQUIT"),
|
|
(int) WalWriterPID)));
|
|
signal_child(WalWriterPID, (SendStop ? SIGSTOP : SIGQUIT));
|
|
}
|
|
|
|
/* Take care of the walreceiver too */
|
|
if (pid == WalReceiverPID)
|
|
WalReceiverPID = 0;
|
|
else if (WalReceiverPID != 0 && !FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
(SendStop ? "SIGSTOP" : "SIGQUIT"),
|
|
(int) WalReceiverPID)));
|
|
signal_child(WalReceiverPID, (SendStop ? SIGSTOP : SIGQUIT));
|
|
}
|
|
|
|
/* Take care of the autovacuum launcher too */
|
|
if (pid == AutoVacPID)
|
|
AutoVacPID = 0;
|
|
else if (AutoVacPID != 0 && !FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
(SendStop ? "SIGSTOP" : "SIGQUIT"),
|
|
(int) AutoVacPID)));
|
|
signal_child(AutoVacPID, (SendStop ? SIGSTOP : SIGQUIT));
|
|
}
|
|
|
|
/*
|
|
* Force a power-cycle of the pgarch process too. (This isn't absolutely
|
|
* necessary, but it seems like a good idea for robustness, and it
|
|
* simplifies the state-machine logic in the case where a shutdown request
|
|
* arrives during crash processing.)
|
|
*/
|
|
if (PgArchPID != 0 && !FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
"SIGQUIT",
|
|
(int) PgArchPID)));
|
|
signal_child(PgArchPID, SIGQUIT);
|
|
}
|
|
|
|
/*
|
|
* Force a power-cycle of the pgstat process too. (This isn't absolutely
|
|
* necessary, but it seems like a good idea for robustness, and it
|
|
* simplifies the state-machine logic in the case where a shutdown request
|
|
* arrives during crash processing.)
|
|
*/
|
|
if (PgStatPID != 0 && !FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
"SIGQUIT",
|
|
(int) PgStatPID)));
|
|
signal_child(PgStatPID, SIGQUIT);
|
|
allow_immediate_pgstat_restart();
|
|
}
|
|
|
|
/* We do NOT restart the syslogger */
|
|
|
|
FatalError = true;
|
|
/* We now transit into a state of waiting for children to die */
|
|
if (pmState == PM_RECOVERY ||
|
|
pmState == PM_RECOVERY_CONSISTENT ||
|
|
pmState == PM_RUN ||
|
|
pmState == PM_WAIT_BACKUP ||
|
|
pmState == PM_WAIT_READONLY ||
|
|
pmState == PM_SHUTDOWN)
|
|
pmState = PM_WAIT_BACKENDS;
|
|
}
|
|
|
|
/*
|
|
* Log the death of a child process.
|
|
*/
|
|
static void
|
|
LogChildExit(int lev, const char *procname, int pid, int exitstatus)
|
|
{
|
|
if (WIFEXITED(exitstatus))
|
|
ereport(lev,
|
|
|
|
/*------
|
|
translator: %s is a noun phrase describing a child process, such as
|
|
"server process" */
|
|
(errmsg("%s (PID %d) exited with exit code %d",
|
|
procname, pid, WEXITSTATUS(exitstatus))));
|
|
else if (WIFSIGNALED(exitstatus))
|
|
#if defined(WIN32)
|
|
ereport(lev,
|
|
|
|
/*------
|
|
translator: %s is a noun phrase describing a child process, such as
|
|
"server process" */
|
|
(errmsg("%s (PID %d) was terminated by exception 0x%X",
|
|
procname, pid, WTERMSIG(exitstatus)),
|
|
errhint("See C include file \"ntstatus.h\" for a description of the hexadecimal value.")));
|
|
#elif defined(HAVE_DECL_SYS_SIGLIST) && HAVE_DECL_SYS_SIGLIST
|
|
ereport(lev,
|
|
|
|
/*------
|
|
translator: %s is a noun phrase describing a child process, such as
|
|
"server process" */
|
|
(errmsg("%s (PID %d) was terminated by signal %d: %s",
|
|
procname, pid, WTERMSIG(exitstatus),
|
|
WTERMSIG(exitstatus) < NSIG ?
|
|
sys_siglist[WTERMSIG(exitstatus)] : "(unknown)")));
|
|
#else
|
|
ereport(lev,
|
|
|
|
/*------
|
|
translator: %s is a noun phrase describing a child process, such as
|
|
"server process" */
|
|
(errmsg("%s (PID %d) was terminated by signal %d",
|
|
procname, pid, WTERMSIG(exitstatus))));
|
|
#endif
|
|
else
|
|
ereport(lev,
|
|
|
|
/*------
|
|
translator: %s is a noun phrase describing a child process, such as
|
|
"server process" */
|
|
(errmsg("%s (PID %d) exited with unrecognized status %d",
|
|
procname, pid, exitstatus)));
|
|
}
|
|
|
|
/*
|
|
* Advance the postmaster's state machine and take actions as appropriate
|
|
*
|
|
* This is common code for pmdie() and reaper(), which receive the signals
|
|
* that might mean we need to change state.
|
|
*/
|
|
static void
|
|
PostmasterStateMachine(void)
|
|
{
|
|
if (pmState == PM_WAIT_BACKUP)
|
|
{
|
|
/*
|
|
* PM_WAIT_BACKUP state ends when online backup mode is not active.
|
|
*/
|
|
if (!BackupInProgress())
|
|
pmState = PM_WAIT_BACKENDS;
|
|
}
|
|
|
|
if (pmState == PM_WAIT_READONLY)
|
|
{
|
|
/*
|
|
* PM_WAIT_READONLY state ends when we have no regular backends that
|
|
* have been started during recovery. We kill the startup and
|
|
* walreceiver processes and transition to PM_WAIT_BACKENDS. Ideally,
|
|
* we might like to kill these processes first and then wait for
|
|
* backends to die off, but that doesn't work at present because
|
|
* killing the startup process doesn't release its locks.
|
|
*/
|
|
if (CountChildren(BACKEND_TYPE_NORMAL) == 0)
|
|
{
|
|
if (StartupPID != 0)
|
|
signal_child(StartupPID, SIGTERM);
|
|
if (WalReceiverPID != 0)
|
|
signal_child(WalReceiverPID, SIGTERM);
|
|
pmState = PM_WAIT_BACKENDS;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we are in a state-machine state that implies waiting for backends to
|
|
* exit, see if they're all gone, and change state if so.
|
|
*/
|
|
if (pmState == PM_WAIT_BACKENDS)
|
|
{
|
|
/*
|
|
* PM_WAIT_BACKENDS state ends when we have no regular backends
|
|
* (including autovac workers) and no walwriter or autovac launcher.
|
|
* If we are doing crash recovery then we expect the bgwriter to exit
|
|
* too, otherwise not. The archiver, stats, and syslogger processes
|
|
* are disregarded since they are not connected to shared memory; we
|
|
* also disregard dead_end children here. Walsenders are also
|
|
* disregarded, they will be terminated later after writing the
|
|
* checkpoint record, like the archiver process.
|
|
*/
|
|
if (CountChildren(BACKEND_TYPE_NORMAL | BACKEND_TYPE_AUTOVAC) == 0 &&
|
|
StartupPID == 0 &&
|
|
WalReceiverPID == 0 &&
|
|
(BgWriterPID == 0 || !FatalError) &&
|
|
WalWriterPID == 0 &&
|
|
AutoVacPID == 0)
|
|
{
|
|
if (FatalError)
|
|
{
|
|
/*
|
|
* Start waiting for dead_end children to die. This state
|
|
* change causes ServerLoop to stop creating new ones.
|
|
*/
|
|
pmState = PM_WAIT_DEAD_END;
|
|
|
|
/*
|
|
* We already SIGQUIT'd the archiver and stats processes, if
|
|
* any, when we entered FatalError state.
|
|
*/
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* If we get here, we are proceeding with normal shutdown. All
|
|
* the regular children are gone, and it's time to tell the
|
|
* bgwriter to do a shutdown checkpoint.
|
|
*/
|
|
Assert(Shutdown > NoShutdown);
|
|
/* Start the bgwriter if not running */
|
|
if (BgWriterPID == 0)
|
|
BgWriterPID = StartBackgroundWriter();
|
|
/* And tell it to shut down */
|
|
if (BgWriterPID != 0)
|
|
{
|
|
signal_child(BgWriterPID, SIGUSR2);
|
|
pmState = PM_SHUTDOWN;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* If we failed to fork a bgwriter, just shut down. Any
|
|
* required cleanup will happen at next restart. We set
|
|
* FatalError so that an "abnormal shutdown" message gets
|
|
* logged when we exit.
|
|
*/
|
|
FatalError = true;
|
|
pmState = PM_WAIT_DEAD_END;
|
|
|
|
/* Kill the walsenders, archiver and stats collector too */
|
|
SignalSomeChildren(SIGQUIT, BACKEND_TYPE_ALL);
|
|
if (PgArchPID != 0)
|
|
signal_child(PgArchPID, SIGQUIT);
|
|
if (PgStatPID != 0)
|
|
signal_child(PgStatPID, SIGQUIT);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (pmState == PM_SHUTDOWN_2)
|
|
{
|
|
/*
|
|
* PM_SHUTDOWN_2 state ends when there's no other children than
|
|
* dead_end children left. There shouldn't be any regular backends
|
|
* left by now anyway; what we're really waiting for is walsenders and
|
|
* archiver.
|
|
*
|
|
* Walreceiver should normally be dead by now, but not when a fast
|
|
* shutdown is performed during recovery.
|
|
*/
|
|
if (PgArchPID == 0 && CountChildren(BACKEND_TYPE_ALL) == 0 &&
|
|
WalReceiverPID == 0)
|
|
{
|
|
pmState = PM_WAIT_DEAD_END;
|
|
}
|
|
}
|
|
|
|
if (pmState == PM_WAIT_DEAD_END)
|
|
{
|
|
/*
|
|
* PM_WAIT_DEAD_END state ends when the BackendList is entirely empty
|
|
* (ie, no dead_end children remain), and the archiver and stats
|
|
* collector are gone too.
|
|
*
|
|
* The reason we wait for those two is to protect them against a new
|
|
* postmaster starting conflicting subprocesses; this isn't an
|
|
* ironclad protection, but it at least helps in the
|
|
* shutdown-and-immediately-restart scenario. Note that they have
|
|
* already been sent appropriate shutdown signals, either during a
|
|
* normal state transition leading up to PM_WAIT_DEAD_END, or during
|
|
* FatalError processing.
|
|
*/
|
|
if (DLGetHead(BackendList) == NULL &&
|
|
PgArchPID == 0 && PgStatPID == 0)
|
|
{
|
|
/* These other guys should be dead already */
|
|
Assert(StartupPID == 0);
|
|
Assert(WalReceiverPID == 0);
|
|
Assert(BgWriterPID == 0);
|
|
Assert(WalWriterPID == 0);
|
|
Assert(AutoVacPID == 0);
|
|
/* syslogger is not considered here */
|
|
pmState = PM_NO_CHILDREN;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we've been told to shut down, we exit as soon as there are no
|
|
* remaining children. If there was a crash, cleanup will occur at the
|
|
* next startup. (Before PostgreSQL 8.3, we tried to recover from the
|
|
* crash before exiting, but that seems unwise if we are quitting because
|
|
* we got SIGTERM from init --- there may well not be time for recovery
|
|
* before init decides to SIGKILL us.)
|
|
*
|
|
* Note that the syslogger continues to run. It will exit when it sees
|
|
* EOF on its input pipe, which happens when there are no more upstream
|
|
* processes.
|
|
*/
|
|
if (Shutdown > NoShutdown && pmState == PM_NO_CHILDREN)
|
|
{
|
|
if (FatalError)
|
|
{
|
|
ereport(LOG, (errmsg("abnormal database system shutdown")));
|
|
ExitPostmaster(1);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Terminate backup mode to avoid recovery after a clean fast
|
|
* shutdown.
|
|
*/
|
|
CancelBackup();
|
|
|
|
/* Normal exit from the postmaster is here */
|
|
ExitPostmaster(0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If recovery failed, wait for all non-syslogger children to exit, and
|
|
* then exit postmaster. We don't try to reinitialize when recovery fails,
|
|
* because more than likely it will just fail again and we will keep
|
|
* trying forever.
|
|
*/
|
|
if (RecoveryError && pmState == PM_NO_CHILDREN)
|
|
ExitPostmaster(1);
|
|
|
|
/*
|
|
* If we need to recover from a crash, wait for all non-syslogger children
|
|
* to exit, then reset shmem and StartupDataBase.
|
|
*/
|
|
if (FatalError && pmState == PM_NO_CHILDREN)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("all server processes terminated; reinitializing")));
|
|
|
|
shmem_exit(1);
|
|
reset_shared(PostPortNumber);
|
|
|
|
StartupPID = StartupDataBase();
|
|
Assert(StartupPID != 0);
|
|
pmState = PM_STARTUP;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Send a signal to a postmaster child process
|
|
*
|
|
* On systems that have setsid(), each child process sets itself up as a
|
|
* process group leader. For signals that are generally interpreted in the
|
|
* appropriate fashion, we signal the entire process group not just the
|
|
* direct child process. This allows us to, for example, SIGQUIT a blocked
|
|
* archive_recovery script, or SIGINT a script being run by a backend via
|
|
* system().
|
|
*
|
|
* There is a race condition for recently-forked children: they might not
|
|
* have executed setsid() yet. So we signal the child directly as well as
|
|
* the group. We assume such a child will handle the signal before trying
|
|
* to spawn any grandchild processes. We also assume that signaling the
|
|
* child twice will not cause any problems.
|
|
*/
|
|
static void
|
|
signal_child(pid_t pid, int signal)
|
|
{
|
|
if (kill(pid, signal) < 0)
|
|
elog(DEBUG3, "kill(%ld,%d) failed: %m", (long) pid, signal);
|
|
#ifdef HAVE_SETSID
|
|
switch (signal)
|
|
{
|
|
case SIGINT:
|
|
case SIGTERM:
|
|
case SIGQUIT:
|
|
case SIGSTOP:
|
|
if (kill(-pid, signal) < 0)
|
|
elog(DEBUG3, "kill(%ld,%d) failed: %m", (long) (-pid), signal);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Send a signal to the targeted children (but NOT special children;
|
|
* dead_end children are never signaled, either).
|
|
*/
|
|
static bool
|
|
SignalSomeChildren(int signal, int target)
|
|
{
|
|
Dlelem *curr;
|
|
bool signaled = false;
|
|
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
Backend *bp = (Backend *) DLE_VAL(curr);
|
|
|
|
if (bp->dead_end)
|
|
continue;
|
|
if (!(target & BACKEND_TYPE_NORMAL) && !bp->is_autovacuum)
|
|
continue;
|
|
if (!(target & BACKEND_TYPE_AUTOVAC) && bp->is_autovacuum)
|
|
continue;
|
|
if (!(target & BACKEND_TYPE_WALSND) &&
|
|
IsPostmasterChildWalSender(bp->child_slot))
|
|
continue;
|
|
|
|
ereport(DEBUG4,
|
|
(errmsg_internal("sending signal %d to process %d",
|
|
signal, (int) bp->pid)));
|
|
signal_child(bp->pid, signal);
|
|
signaled = true;
|
|
}
|
|
return signaled;
|
|
}
|
|
|
|
/*
|
|
* BackendStartup -- start backend process
|
|
*
|
|
* returns: STATUS_ERROR if the fork failed, STATUS_OK otherwise.
|
|
*
|
|
* Note: if you change this code, also consider StartAutovacuumWorker.
|
|
*/
|
|
static int
|
|
BackendStartup(Port *port)
|
|
{
|
|
Backend *bn; /* for backend cleanup */
|
|
pid_t pid;
|
|
|
|
/*
|
|
* Create backend data structure. Better before the fork() so we can
|
|
* handle failure cleanly.
|
|
*/
|
|
bn = (Backend *) malloc(sizeof(Backend));
|
|
if (!bn)
|
|
{
|
|
ereport(LOG,
|
|
(errcode(ERRCODE_OUT_OF_MEMORY),
|
|
errmsg("out of memory")));
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
/*
|
|
* Compute the cancel key that will be assigned to this backend. The
|
|
* backend will have its own copy in the forked-off process' value of
|
|
* MyCancelKey, so that it can transmit the key to the frontend.
|
|
*/
|
|
MyCancelKey = PostmasterRandom();
|
|
bn->cancel_key = MyCancelKey;
|
|
|
|
/* Pass down canAcceptConnections state */
|
|
port->canAcceptConnections = canAcceptConnections();
|
|
bn->dead_end = (port->canAcceptConnections != CAC_OK &&
|
|
port->canAcceptConnections != CAC_WAITBACKUP);
|
|
|
|
/*
|
|
* Unless it's a dead_end child, assign it a child slot number
|
|
*/
|
|
if (!bn->dead_end)
|
|
bn->child_slot = MyPMChildSlot = AssignPostmasterChildSlot();
|
|
else
|
|
bn->child_slot = 0;
|
|
|
|
#ifdef EXEC_BACKEND
|
|
pid = backend_forkexec(port);
|
|
#else /* !EXEC_BACKEND */
|
|
pid = fork_process();
|
|
if (pid == 0) /* child */
|
|
{
|
|
free(bn);
|
|
|
|
/*
|
|
* Let's clean up ourselves as the postmaster child, and close the
|
|
* postmaster's listen sockets. (In EXEC_BACKEND case this is all
|
|
* done in SubPostmasterMain.)
|
|
*/
|
|
IsUnderPostmaster = true; /* we are a postmaster subprocess now */
|
|
|
|
MyProcPid = getpid(); /* reset MyProcPid */
|
|
|
|
MyStartTime = time(NULL);
|
|
|
|
/* We don't want the postmaster's proc_exit() handlers */
|
|
on_exit_reset();
|
|
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(false);
|
|
|
|
/* Perform additional initialization and collect startup packet */
|
|
BackendInitialize(port);
|
|
|
|
/* And run the backend */
|
|
proc_exit(BackendRun(port));
|
|
}
|
|
#endif /* EXEC_BACKEND */
|
|
|
|
if (pid < 0)
|
|
{
|
|
/* in parent, fork failed */
|
|
int save_errno = errno;
|
|
|
|
if (!bn->dead_end)
|
|
(void) ReleasePostmasterChildSlot(bn->child_slot);
|
|
free(bn);
|
|
errno = save_errno;
|
|
ereport(LOG,
|
|
(errmsg("could not fork new process for connection: %m")));
|
|
report_fork_failure_to_client(port, save_errno);
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
/* in parent, successful fork */
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("forked new backend, pid=%d socket=%d",
|
|
(int) pid, port->sock)));
|
|
|
|
/*
|
|
* Everything's been successful, it's safe to add this backend to our list
|
|
* of backends.
|
|
*/
|
|
bn->pid = pid;
|
|
bn->is_autovacuum = false;
|
|
DLInitElem(&bn->elem, bn);
|
|
DLAddHead(BackendList, &bn->elem);
|
|
#ifdef EXEC_BACKEND
|
|
if (!bn->dead_end)
|
|
ShmemBackendArrayAdd(bn);
|
|
#endif
|
|
|
|
return STATUS_OK;
|
|
}
|
|
|
|
/*
|
|
* Try to report backend fork() failure to client before we close the
|
|
* connection. Since we do not care to risk blocking the postmaster on
|
|
* this connection, we set the connection to non-blocking and try only once.
|
|
*
|
|
* This is grungy special-purpose code; we cannot use backend libpq since
|
|
* it's not up and running.
|
|
*/
|
|
static void
|
|
report_fork_failure_to_client(Port *port, int errnum)
|
|
{
|
|
char buffer[1000];
|
|
int rc;
|
|
|
|
/* Format the error message packet (always V2 protocol) */
|
|
snprintf(buffer, sizeof(buffer), "E%s%s\n",
|
|
_("could not fork new process for connection: "),
|
|
strerror(errnum));
|
|
|
|
/* Set port to non-blocking. Don't do send() if this fails */
|
|
if (!pg_set_noblock(port->sock))
|
|
return;
|
|
|
|
/* We'll retry after EINTR, but ignore all other failures */
|
|
do
|
|
{
|
|
rc = send(port->sock, buffer, strlen(buffer) + 1, 0);
|
|
} while (rc < 0 && errno == EINTR);
|
|
}
|
|
|
|
|
|
/*
|
|
* BackendInitialize -- initialize an interactive (postmaster-child)
|
|
* backend process, and collect the client's startup packet.
|
|
*
|
|
* returns: nothing. Will not return at all if there's any failure.
|
|
*
|
|
* Note: this code does not depend on having any access to shared memory.
|
|
* In the EXEC_BACKEND case, we are physically attached to shared memory
|
|
* but have not yet set up most of our local pointers to shmem structures.
|
|
*/
|
|
static void
|
|
BackendInitialize(Port *port)
|
|
{
|
|
int status;
|
|
char remote_host[NI_MAXHOST];
|
|
char remote_port[NI_MAXSERV];
|
|
char remote_ps_data[NI_MAXHOST];
|
|
|
|
/* Save port etc. for ps status */
|
|
MyProcPort = port;
|
|
|
|
/*
|
|
* PreAuthDelay is a debugging aid for investigating problems in the
|
|
* authentication cycle: it can be set in postgresql.conf to allow time to
|
|
* attach to the newly-forked backend with a debugger. (See also
|
|
* PostAuthDelay, which we allow clients to pass through PGOPTIONS, but it
|
|
* is not honored until after authentication.)
|
|
*/
|
|
if (PreAuthDelay > 0)
|
|
pg_usleep(PreAuthDelay * 1000000L);
|
|
|
|
/* This flag will remain set until InitPostgres finishes authentication */
|
|
ClientAuthInProgress = true; /* limit visibility of log messages */
|
|
|
|
/* save process start time */
|
|
port->SessionStartTime = GetCurrentTimestamp();
|
|
MyStartTime = timestamptz_to_time_t(port->SessionStartTime);
|
|
|
|
/* set these to empty in case they are needed before we set them up */
|
|
port->remote_host = "";
|
|
port->remote_port = "";
|
|
|
|
/*
|
|
* Initialize libpq and enable reporting of ereport errors to the client.
|
|
* Must do this now because authentication uses libpq to send messages.
|
|
*/
|
|
pq_init(); /* initialize libpq to talk to client */
|
|
whereToSendOutput = DestRemote; /* now safe to ereport to client */
|
|
|
|
/*
|
|
* If possible, make this process a group leader, so that the postmaster
|
|
* can signal any child processes too. (We do this now on the off chance
|
|
* that something might spawn a child process during authentication.)
|
|
*/
|
|
#ifdef HAVE_SETSID
|
|
if (setsid() < 0)
|
|
elog(FATAL, "setsid() failed: %m");
|
|
#endif
|
|
|
|
/*
|
|
* We arrange for a simple exit(1) if we receive SIGTERM or SIGQUIT or
|
|
* timeout while trying to collect the startup packet. Otherwise the
|
|
* postmaster cannot shutdown the database FAST or IMMED cleanly if a
|
|
* buggy client fails to send the packet promptly.
|
|
*/
|
|
pqsignal(SIGTERM, startup_die);
|
|
pqsignal(SIGQUIT, startup_die);
|
|
pqsignal(SIGALRM, startup_die);
|
|
PG_SETMASK(&StartupBlockSig);
|
|
|
|
/*
|
|
* Get the remote host name and port for logging and status display.
|
|
*/
|
|
remote_host[0] = '\0';
|
|
remote_port[0] = '\0';
|
|
if (pg_getnameinfo_all(&port->raddr.addr, port->raddr.salen,
|
|
remote_host, sizeof(remote_host),
|
|
remote_port, sizeof(remote_port),
|
|
(log_hostname ? 0 : NI_NUMERICHOST) | NI_NUMERICSERV))
|
|
{
|
|
int ret = pg_getnameinfo_all(&port->raddr.addr, port->raddr.salen,
|
|
remote_host, sizeof(remote_host),
|
|
remote_port, sizeof(remote_port),
|
|
NI_NUMERICHOST | NI_NUMERICSERV);
|
|
|
|
if (ret)
|
|
ereport(WARNING,
|
|
(errmsg_internal("pg_getnameinfo_all() failed: %s",
|
|
gai_strerror(ret))));
|
|
}
|
|
snprintf(remote_ps_data, sizeof(remote_ps_data),
|
|
remote_port[0] == '\0' ? "%s" : "%s(%s)",
|
|
remote_host, remote_port);
|
|
|
|
if (Log_connections)
|
|
{
|
|
if (remote_port[0])
|
|
ereport(LOG,
|
|
(errmsg("connection received: host=%s port=%s",
|
|
remote_host,
|
|
remote_port)));
|
|
else
|
|
ereport(LOG,
|
|
(errmsg("connection received: host=%s",
|
|
remote_host)));
|
|
}
|
|
|
|
/*
|
|
* save remote_host and remote_port in port structure
|
|
*/
|
|
port->remote_host = strdup(remote_host);
|
|
port->remote_port = strdup(remote_port);
|
|
|
|
/*
|
|
* Ready to begin client interaction. We will give up and exit(1) after a
|
|
* time delay, so that a broken client can't hog a connection
|
|
* indefinitely. PreAuthDelay and any DNS interactions above don't count
|
|
* against the time limit.
|
|
*/
|
|
if (!enable_sig_alarm(AuthenticationTimeout * 1000, false))
|
|
elog(FATAL, "could not set timer for startup packet timeout");
|
|
|
|
/*
|
|
* Receive the startup packet (which might turn out to be a cancel request
|
|
* packet).
|
|
*/
|
|
status = ProcessStartupPacket(port, false);
|
|
|
|
/*
|
|
* Stop here if it was bad or a cancel packet. ProcessStartupPacket
|
|
* already did any appropriate error reporting.
|
|
*/
|
|
if (status != STATUS_OK)
|
|
proc_exit(0);
|
|
|
|
/*
|
|
* Now that we have the user and database name, we can set the process
|
|
* title for ps. It's good to do this as early as possible in startup.
|
|
*
|
|
* For a walsender, the ps display is set in the following form:
|
|
*
|
|
* postgres: wal sender process <user> <host> <activity>
|
|
*
|
|
* To achieve that, we pass "wal sender process" as username and username
|
|
* as dbname to init_ps_display(). XXX: should add a new variant of
|
|
* init_ps_display() to avoid abusing the parameters like this.
|
|
*/
|
|
if (am_walsender)
|
|
init_ps_display("wal sender process", port->user_name, remote_ps_data,
|
|
update_process_title ? "authentication" : "");
|
|
else
|
|
init_ps_display(port->user_name, port->database_name, remote_ps_data,
|
|
update_process_title ? "authentication" : "");
|
|
|
|
/*
|
|
* Disable the timeout, and prevent SIGTERM/SIGQUIT again.
|
|
*/
|
|
if (!disable_sig_alarm(false))
|
|
elog(FATAL, "could not disable timer for startup packet timeout");
|
|
PG_SETMASK(&BlockSig);
|
|
}
|
|
|
|
|
|
/*
|
|
* BackendRun -- set up the backend's argument list and invoke PostgresMain()
|
|
*
|
|
* returns:
|
|
* Shouldn't return at all.
|
|
* If PostgresMain() fails, return status.
|
|
*/
|
|
static int
|
|
BackendRun(Port *port)
|
|
{
|
|
char **av;
|
|
int maxac;
|
|
int ac;
|
|
long secs;
|
|
int usecs;
|
|
int i;
|
|
|
|
/*
|
|
* Don't want backend to be able to see the postmaster random number
|
|
* generator state. We have to clobber the static random_seed *and* start
|
|
* a new random sequence in the random() library function.
|
|
*/
|
|
random_seed = 0;
|
|
random_start_time.tv_usec = 0;
|
|
/* slightly hacky way to get integer microseconds part of timestamptz */
|
|
TimestampDifference(0, port->SessionStartTime, &secs, &usecs);
|
|
srandom((unsigned int) (MyProcPid ^ usecs));
|
|
|
|
/*
|
|
* Now, build the argv vector that will be given to PostgresMain.
|
|
*
|
|
* The maximum possible number of commandline arguments that could come
|
|
* from ExtraOptions is (strlen(ExtraOptions) + 1) / 2; see
|
|
* pg_split_opts().
|
|
*/
|
|
maxac = 5; /* for fixed args supplied below */
|
|
maxac += (strlen(ExtraOptions) + 1) / 2;
|
|
|
|
av = (char **) MemoryContextAlloc(TopMemoryContext,
|
|
maxac * sizeof(char *));
|
|
ac = 0;
|
|
|
|
av[ac++] = "postgres";
|
|
|
|
/*
|
|
* Pass any backend switches specified with -o on the postmaster's own
|
|
* command line. We assume these are secure. (It's OK to mangle
|
|
* ExtraOptions now, since we're safely inside a subprocess.)
|
|
*/
|
|
pg_split_opts(av, &ac, ExtraOptions);
|
|
|
|
/*
|
|
* Tell the backend which database to use.
|
|
*/
|
|
av[ac++] = port->database_name;
|
|
|
|
av[ac] = NULL;
|
|
|
|
Assert(ac < maxac);
|
|
|
|
/*
|
|
* Debug: print arguments being passed to backend
|
|
*/
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("%s child[%d]: starting with (",
|
|
progname, (int) getpid())));
|
|
for (i = 0; i < ac; ++i)
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("\t%s", av[i])));
|
|
ereport(DEBUG3,
|
|
(errmsg_internal(")")));
|
|
|
|
/*
|
|
* Make sure we aren't in PostmasterContext anymore. (We can't delete it
|
|
* just yet, though, because InitPostgres will need the HBA data.)
|
|
*/
|
|
MemoryContextSwitchTo(TopMemoryContext);
|
|
|
|
return (PostgresMain(ac, av, port->user_name));
|
|
}
|
|
|
|
|
|
#ifdef EXEC_BACKEND
|
|
|
|
/*
|
|
* postmaster_forkexec -- fork and exec a postmaster subprocess
|
|
*
|
|
* The caller must have set up the argv array already, except for argv[2]
|
|
* which will be filled with the name of the temp variable file.
|
|
*
|
|
* Returns the child process PID, or -1 on fork failure (a suitable error
|
|
* message has been logged on failure).
|
|
*
|
|
* All uses of this routine will dispatch to SubPostmasterMain in the
|
|
* child process.
|
|
*/
|
|
pid_t
|
|
postmaster_forkexec(int argc, char *argv[])
|
|
{
|
|
Port port;
|
|
|
|
/* This entry point passes dummy values for the Port variables */
|
|
memset(&port, 0, sizeof(port));
|
|
return internal_forkexec(argc, argv, &port);
|
|
}
|
|
|
|
/*
|
|
* backend_forkexec -- fork/exec off a backend process
|
|
*
|
|
* Some operating systems (WIN32) don't have fork() so we have to simulate
|
|
* it by storing parameters that need to be passed to the child and
|
|
* then create a new child process.
|
|
*
|
|
* returns the pid of the fork/exec'd process, or -1 on failure
|
|
*/
|
|
static pid_t
|
|
backend_forkexec(Port *port)
|
|
{
|
|
char *av[4];
|
|
int ac = 0;
|
|
|
|
av[ac++] = "postgres";
|
|
av[ac++] = "--forkbackend";
|
|
av[ac++] = NULL; /* filled in by internal_forkexec */
|
|
|
|
av[ac] = NULL;
|
|
Assert(ac < lengthof(av));
|
|
|
|
return internal_forkexec(ac, av, port);
|
|
}
|
|
|
|
#ifndef WIN32
|
|
|
|
/*
|
|
* internal_forkexec non-win32 implementation
|
|
*
|
|
* - writes out backend variables to the parameter file
|
|
* - fork():s, and then exec():s the child process
|
|
*/
|
|
static pid_t
|
|
internal_forkexec(int argc, char *argv[], Port *port)
|
|
{
|
|
static unsigned long tmpBackendFileNum = 0;
|
|
pid_t pid;
|
|
char tmpfilename[MAXPGPATH];
|
|
BackendParameters param;
|
|
FILE *fp;
|
|
|
|
if (!save_backend_variables(¶m, port))
|
|
return -1; /* log made by save_backend_variables */
|
|
|
|
/* Calculate name for temp file */
|
|
snprintf(tmpfilename, MAXPGPATH, "%s/%s.backend_var.%d.%lu",
|
|
PG_TEMP_FILES_DIR, PG_TEMP_FILE_PREFIX,
|
|
MyProcPid, ++tmpBackendFileNum);
|
|
|
|
/* Open file */
|
|
fp = AllocateFile(tmpfilename, PG_BINARY_W);
|
|
if (!fp)
|
|
{
|
|
/* As in OpenTemporaryFile, try to make the temp-file directory */
|
|
mkdir(PG_TEMP_FILES_DIR, S_IRWXU);
|
|
|
|
fp = AllocateFile(tmpfilename, PG_BINARY_W);
|
|
if (!fp)
|
|
{
|
|
ereport(LOG,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create file \"%s\": %m",
|
|
tmpfilename)));
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
if (fwrite(¶m, sizeof(param), 1, fp) != 1)
|
|
{
|
|
ereport(LOG,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to file \"%s\": %m", tmpfilename)));
|
|
FreeFile(fp);
|
|
return -1;
|
|
}
|
|
|
|
/* Release file */
|
|
if (FreeFile(fp))
|
|
{
|
|
ereport(LOG,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to file \"%s\": %m", tmpfilename)));
|
|
return -1;
|
|
}
|
|
|
|
/* Make sure caller set up argv properly */
|
|
Assert(argc >= 3);
|
|
Assert(argv[argc] == NULL);
|
|
Assert(strncmp(argv[1], "--fork", 6) == 0);
|
|
Assert(argv[2] == NULL);
|
|
|
|
/* Insert temp file name after --fork argument */
|
|
argv[2] = tmpfilename;
|
|
|
|
/* Fire off execv in child */
|
|
if ((pid = fork_process()) == 0)
|
|
{
|
|
if (execv(postgres_exec_path, argv) < 0)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("could not execute server process \"%s\": %m",
|
|
postgres_exec_path)));
|
|
/* We're already in the child process here, can't return */
|
|
exit(1);
|
|
}
|
|
}
|
|
|
|
return pid; /* Parent returns pid, or -1 on fork failure */
|
|
}
|
|
#else /* WIN32 */
|
|
|
|
/*
|
|
* internal_forkexec win32 implementation
|
|
*
|
|
* - starts backend using CreateProcess(), in suspended state
|
|
* - writes out backend variables to the parameter file
|
|
* - during this, duplicates handles and sockets required for
|
|
* inheritance into the new process
|
|
* - resumes execution of the new process once the backend parameter
|
|
* file is complete.
|
|
*/
|
|
static pid_t
|
|
internal_forkexec(int argc, char *argv[], Port *port)
|
|
{
|
|
STARTUPINFO si;
|
|
PROCESS_INFORMATION pi;
|
|
int i;
|
|
int j;
|
|
char cmdLine[MAXPGPATH * 2];
|
|
HANDLE paramHandle;
|
|
BackendParameters *param;
|
|
SECURITY_ATTRIBUTES sa;
|
|
char paramHandleStr[32];
|
|
win32_deadchild_waitinfo *childinfo;
|
|
|
|
/* Make sure caller set up argv properly */
|
|
Assert(argc >= 3);
|
|
Assert(argv[argc] == NULL);
|
|
Assert(strncmp(argv[1], "--fork", 6) == 0);
|
|
Assert(argv[2] == NULL);
|
|
|
|
/* Set up shared memory for parameter passing */
|
|
ZeroMemory(&sa, sizeof(sa));
|
|
sa.nLength = sizeof(sa);
|
|
sa.bInheritHandle = TRUE;
|
|
paramHandle = CreateFileMapping(INVALID_HANDLE_VALUE,
|
|
&sa,
|
|
PAGE_READWRITE,
|
|
0,
|
|
sizeof(BackendParameters),
|
|
NULL);
|
|
if (paramHandle == INVALID_HANDLE_VALUE)
|
|
{
|
|
elog(LOG, "could not create backend parameter file mapping: error code %d",
|
|
(int) GetLastError());
|
|
return -1;
|
|
}
|
|
|
|
param = MapViewOfFile(paramHandle, FILE_MAP_WRITE, 0, 0, sizeof(BackendParameters));
|
|
if (!param)
|
|
{
|
|
elog(LOG, "could not map backend parameter memory: error code %d",
|
|
(int) GetLastError());
|
|
CloseHandle(paramHandle);
|
|
return -1;
|
|
}
|
|
|
|
/* Insert temp file name after --fork argument */
|
|
sprintf(paramHandleStr, "%lu", (DWORD) paramHandle);
|
|
argv[2] = paramHandleStr;
|
|
|
|
/* Format the cmd line */
|
|
cmdLine[sizeof(cmdLine) - 1] = '\0';
|
|
cmdLine[sizeof(cmdLine) - 2] = '\0';
|
|
snprintf(cmdLine, sizeof(cmdLine) - 1, "\"%s\"", postgres_exec_path);
|
|
i = 0;
|
|
while (argv[++i] != NULL)
|
|
{
|
|
j = strlen(cmdLine);
|
|
snprintf(cmdLine + j, sizeof(cmdLine) - 1 - j, " \"%s\"", argv[i]);
|
|
}
|
|
if (cmdLine[sizeof(cmdLine) - 2] != '\0')
|
|
{
|
|
elog(LOG, "subprocess command line too long");
|
|
return -1;
|
|
}
|
|
|
|
memset(&pi, 0, sizeof(pi));
|
|
memset(&si, 0, sizeof(si));
|
|
si.cb = sizeof(si);
|
|
|
|
/*
|
|
* Create the subprocess in a suspended state. This will be resumed later,
|
|
* once we have written out the parameter file.
|
|
*/
|
|
if (!CreateProcess(NULL, cmdLine, NULL, NULL, TRUE, CREATE_SUSPENDED,
|
|
NULL, NULL, &si, &pi))
|
|
{
|
|
elog(LOG, "CreateProcess call failed: %m (error code %d)",
|
|
(int) GetLastError());
|
|
return -1;
|
|
}
|
|
|
|
if (!save_backend_variables(param, port, pi.hProcess, pi.dwProcessId))
|
|
{
|
|
/*
|
|
* log made by save_backend_variables, but we have to clean up the
|
|
* mess with the half-started process
|
|
*/
|
|
if (!TerminateProcess(pi.hProcess, 255))
|
|
ereport(LOG,
|
|
(errmsg_internal("could not terminate unstarted process: error code %d",
|
|
(int) GetLastError())));
|
|
CloseHandle(pi.hProcess);
|
|
CloseHandle(pi.hThread);
|
|
return -1; /* log made by save_backend_variables */
|
|
}
|
|
|
|
/* Drop the parameter shared memory that is now inherited to the backend */
|
|
if (!UnmapViewOfFile(param))
|
|
elog(LOG, "could not unmap view of backend parameter file: error code %d",
|
|
(int) GetLastError());
|
|
if (!CloseHandle(paramHandle))
|
|
elog(LOG, "could not close handle to backend parameter file: error code %d",
|
|
(int) GetLastError());
|
|
|
|
/*
|
|
* Reserve the memory region used by our main shared memory segment before
|
|
* we resume the child process.
|
|
*/
|
|
if (!pgwin32_ReserveSharedMemoryRegion(pi.hProcess))
|
|
{
|
|
/*
|
|
* Failed to reserve the memory, so terminate the newly created
|
|
* process and give up.
|
|
*/
|
|
if (!TerminateProcess(pi.hProcess, 255))
|
|
ereport(LOG,
|
|
(errmsg_internal("could not terminate process that failed to reserve memory: error code %d",
|
|
(int) GetLastError())));
|
|
CloseHandle(pi.hProcess);
|
|
CloseHandle(pi.hThread);
|
|
return -1; /* logging done made by
|
|
* pgwin32_ReserveSharedMemoryRegion() */
|
|
}
|
|
|
|
/*
|
|
* Now that the backend variables are written out, we start the child
|
|
* thread so it can start initializing while we set up the rest of the
|
|
* parent state.
|
|
*/
|
|
if (ResumeThread(pi.hThread) == -1)
|
|
{
|
|
if (!TerminateProcess(pi.hProcess, 255))
|
|
{
|
|
ereport(LOG,
|
|
(errmsg_internal("could not terminate unstartable process: error code %d",
|
|
(int) GetLastError())));
|
|
CloseHandle(pi.hProcess);
|
|
CloseHandle(pi.hThread);
|
|
return -1;
|
|
}
|
|
CloseHandle(pi.hProcess);
|
|
CloseHandle(pi.hThread);
|
|
ereport(LOG,
|
|
(errmsg_internal("could not resume thread of unstarted process: error code %d",
|
|
(int) GetLastError())));
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Queue a waiter for to signal when this child dies. The wait will be
|
|
* handled automatically by an operating system thread pool.
|
|
*
|
|
* Note: use malloc instead of palloc, since it needs to be thread-safe.
|
|
* Struct will be free():d from the callback function that runs on a
|
|
* different thread.
|
|
*/
|
|
childinfo = malloc(sizeof(win32_deadchild_waitinfo));
|
|
if (!childinfo)
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OUT_OF_MEMORY),
|
|
errmsg("out of memory")));
|
|
|
|
childinfo->procHandle = pi.hProcess;
|
|
childinfo->procId = pi.dwProcessId;
|
|
|
|
if (!RegisterWaitForSingleObject(&childinfo->waitHandle,
|
|
pi.hProcess,
|
|
pgwin32_deadchild_callback,
|
|
childinfo,
|
|
INFINITE,
|
|
WT_EXECUTEONLYONCE | WT_EXECUTEINWAITTHREAD))
|
|
ereport(FATAL,
|
|
(errmsg_internal("could not register process for wait: error code %d",
|
|
(int) GetLastError())));
|
|
|
|
/* Don't close pi.hProcess here - the wait thread needs access to it */
|
|
|
|
CloseHandle(pi.hThread);
|
|
|
|
return pi.dwProcessId;
|
|
}
|
|
#endif /* WIN32 */
|
|
|
|
|
|
/*
|
|
* SubPostmasterMain -- Get the fork/exec'd process into a state equivalent
|
|
* to what it would be if we'd simply forked on Unix, and then
|
|
* dispatch to the appropriate place.
|
|
*
|
|
* The first two command line arguments are expected to be "--forkFOO"
|
|
* (where FOO indicates which postmaster child we are to become), and
|
|
* the name of a variables file that we can read to load data that would
|
|
* have been inherited by fork() on Unix. Remaining arguments go to the
|
|
* subprocess FooMain() routine.
|
|
*/
|
|
int
|
|
SubPostmasterMain(int argc, char *argv[])
|
|
{
|
|
Port port;
|
|
|
|
/* Do this sooner rather than later... */
|
|
IsUnderPostmaster = true; /* we are a postmaster subprocess now */
|
|
|
|
MyProcPid = getpid(); /* reset MyProcPid */
|
|
|
|
MyStartTime = time(NULL);
|
|
|
|
/*
|
|
* make sure stderr is in binary mode before anything can possibly be
|
|
* written to it, in case it's actually the syslogger pipe, so the pipe
|
|
* chunking protocol isn't disturbed. Non-logpipe data gets translated on
|
|
* redirection (e.g. via pg_ctl -l) anyway.
|
|
*/
|
|
#ifdef WIN32
|
|
_setmode(fileno(stderr), _O_BINARY);
|
|
#endif
|
|
|
|
/* Lose the postmaster's on-exit routines (really a no-op) */
|
|
on_exit_reset();
|
|
|
|
/* In EXEC_BACKEND case we will not have inherited these settings */
|
|
IsPostmasterEnvironment = true;
|
|
whereToSendOutput = DestNone;
|
|
|
|
/* Setup essential subsystems (to ensure elog() behaves sanely) */
|
|
MemoryContextInit();
|
|
InitializeGUCOptions();
|
|
|
|
/* Read in the variables file */
|
|
memset(&port, 0, sizeof(Port));
|
|
read_backend_variables(argv[2], &port);
|
|
|
|
/*
|
|
* Set up memory area for GSS information. Mirrors the code in ConnCreate
|
|
* for the non-exec case.
|
|
*/
|
|
#if defined(ENABLE_GSS) || defined(ENABLE_SSPI)
|
|
port.gss = (pg_gssinfo *) calloc(1, sizeof(pg_gssinfo));
|
|
if (!port.gss)
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OUT_OF_MEMORY),
|
|
errmsg("out of memory")));
|
|
#endif
|
|
|
|
/* Check we got appropriate args */
|
|
if (argc < 3)
|
|
elog(FATAL, "invalid subpostmaster invocation");
|
|
|
|
/*
|
|
* If appropriate, physically re-attach to shared memory segment. We want
|
|
* to do this before going any further to ensure that we can attach at the
|
|
* same address the postmaster used.
|
|
*/
|
|
if (strcmp(argv[1], "--forkbackend") == 0 ||
|
|
strcmp(argv[1], "--forkavlauncher") == 0 ||
|
|
strcmp(argv[1], "--forkavworker") == 0 ||
|
|
strcmp(argv[1], "--forkboot") == 0)
|
|
PGSharedMemoryReAttach();
|
|
|
|
/* autovacuum needs this set before calling InitProcess */
|
|
if (strcmp(argv[1], "--forkavlauncher") == 0)
|
|
AutovacuumLauncherIAm();
|
|
if (strcmp(argv[1], "--forkavworker") == 0)
|
|
AutovacuumWorkerIAm();
|
|
|
|
/*
|
|
* Start our win32 signal implementation. This has to be done after we
|
|
* read the backend variables, because we need to pick up the signal pipe
|
|
* from the parent process.
|
|
*/
|
|
#ifdef WIN32
|
|
pgwin32_signal_initialize();
|
|
#endif
|
|
|
|
/* In EXEC_BACKEND case we will not have inherited these settings */
|
|
pqinitmask();
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
/* Read in remaining GUC variables */
|
|
read_nondefault_variables();
|
|
|
|
/*
|
|
* Reload any libraries that were preloaded by the postmaster. Since we
|
|
* exec'd this process, those libraries didn't come along with us; but we
|
|
* should load them into all child processes to be consistent with the
|
|
* non-EXEC_BACKEND behavior.
|
|
*/
|
|
process_shared_preload_libraries();
|
|
|
|
/* Run backend or appropriate child */
|
|
if (strcmp(argv[1], "--forkbackend") == 0)
|
|
{
|
|
Assert(argc == 3); /* shouldn't be any more args */
|
|
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(false);
|
|
|
|
/*
|
|
* Need to reinitialize the SSL library in the backend, since the
|
|
* context structures contain function pointers and cannot be passed
|
|
* through the parameter file.
|
|
*
|
|
* XXX should we do this in all child processes? For the moment it's
|
|
* enough to do it in backend children.
|
|
*/
|
|
#ifdef USE_SSL
|
|
if (EnableSSL)
|
|
secure_initialize();
|
|
#endif
|
|
|
|
/*
|
|
* Perform additional initialization and collect startup packet.
|
|
*
|
|
* We want to do this before InitProcess() for a couple of reasons: 1.
|
|
* so that we aren't eating up a PGPROC slot while waiting on the
|
|
* client. 2. so that if InitProcess() fails due to being out of
|
|
* PGPROC slots, we have already initialized libpq and are able to
|
|
* report the error to the client.
|
|
*/
|
|
BackendInitialize(&port);
|
|
|
|
/* Restore basic shared memory pointers */
|
|
InitShmemAccess(UsedShmemSegAddr);
|
|
|
|
/* Need a PGPROC to run CreateSharedMemoryAndSemaphores */
|
|
InitProcess();
|
|
|
|
/*
|
|
* Attach process to shared data structures. If testing EXEC_BACKEND
|
|
* on Linux, you must run this as root before starting the postmaster:
|
|
*
|
|
* echo 0 >/proc/sys/kernel/randomize_va_space
|
|
*
|
|
* This prevents a randomized stack base address that causes child
|
|
* shared memory to be at a different address than the parent, making
|
|
* it impossible to attached to shared memory. Return the value to
|
|
* '1' when finished.
|
|
*/
|
|
CreateSharedMemoryAndSemaphores(false, 0);
|
|
|
|
/* And run the backend */
|
|
proc_exit(BackendRun(&port));
|
|
}
|
|
if (strcmp(argv[1], "--forkboot") == 0)
|
|
{
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(false);
|
|
|
|
/* Restore basic shared memory pointers */
|
|
InitShmemAccess(UsedShmemSegAddr);
|
|
|
|
/* Need a PGPROC to run CreateSharedMemoryAndSemaphores */
|
|
InitAuxiliaryProcess();
|
|
|
|
/* Attach process to shared data structures */
|
|
CreateSharedMemoryAndSemaphores(false, 0);
|
|
|
|
AuxiliaryProcessMain(argc - 2, argv + 2);
|
|
proc_exit(0);
|
|
}
|
|
if (strcmp(argv[1], "--forkavlauncher") == 0)
|
|
{
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(false);
|
|
|
|
/* Restore basic shared memory pointers */
|
|
InitShmemAccess(UsedShmemSegAddr);
|
|
|
|
/* Need a PGPROC to run CreateSharedMemoryAndSemaphores */
|
|
InitProcess();
|
|
|
|
/* Attach process to shared data structures */
|
|
CreateSharedMemoryAndSemaphores(false, 0);
|
|
|
|
AutoVacLauncherMain(argc - 2, argv + 2);
|
|
proc_exit(0);
|
|
}
|
|
if (strcmp(argv[1], "--forkavworker") == 0)
|
|
{
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(false);
|
|
|
|
/* Restore basic shared memory pointers */
|
|
InitShmemAccess(UsedShmemSegAddr);
|
|
|
|
/* Need a PGPROC to run CreateSharedMemoryAndSemaphores */
|
|
InitProcess();
|
|
|
|
/* Attach process to shared data structures */
|
|
CreateSharedMemoryAndSemaphores(false, 0);
|
|
|
|
AutoVacWorkerMain(argc - 2, argv + 2);
|
|
proc_exit(0);
|
|
}
|
|
if (strcmp(argv[1], "--forkarch") == 0)
|
|
{
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(false);
|
|
|
|
/* Do not want to attach to shared memory */
|
|
|
|
PgArchiverMain(argc, argv);
|
|
proc_exit(0);
|
|
}
|
|
if (strcmp(argv[1], "--forkcol") == 0)
|
|
{
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(false);
|
|
|
|
/* Do not want to attach to shared memory */
|
|
|
|
PgstatCollectorMain(argc, argv);
|
|
proc_exit(0);
|
|
}
|
|
if (strcmp(argv[1], "--forklog") == 0)
|
|
{
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(true);
|
|
|
|
/* Do not want to attach to shared memory */
|
|
|
|
SysLoggerMain(argc, argv);
|
|
proc_exit(0);
|
|
}
|
|
|
|
return 1; /* shouldn't get here */
|
|
}
|
|
#endif /* EXEC_BACKEND */
|
|
|
|
|
|
/*
|
|
* ExitPostmaster -- cleanup
|
|
*
|
|
* Do NOT call exit() directly --- always go through here!
|
|
*/
|
|
static void
|
|
ExitPostmaster(int status)
|
|
{
|
|
/* should cleanup shared memory and kill all backends */
|
|
|
|
/*
|
|
* Not sure of the semantics here. When the Postmaster dies, should the
|
|
* backends all be killed? probably not.
|
|
*
|
|
* MUST -- vadim 05-10-1999
|
|
*/
|
|
|
|
proc_exit(status);
|
|
}
|
|
|
|
/*
|
|
* sigusr1_handler - handle signal conditions from child processes
|
|
*/
|
|
static void
|
|
sigusr1_handler(SIGNAL_ARGS)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
/*
|
|
* RECOVERY_STARTED and RECOVERY_CONSISTENT signals are ignored in
|
|
* unexpected states. If the startup process quickly starts up, completes
|
|
* recovery, exits, we might process the death of the startup process
|
|
* first. We don't want to go back to recovery in that case.
|
|
*/
|
|
if (CheckPostmasterSignal(PMSIGNAL_RECOVERY_STARTED) &&
|
|
pmState == PM_STARTUP)
|
|
{
|
|
/* WAL redo has started. We're out of reinitialization. */
|
|
FatalError = false;
|
|
|
|
/*
|
|
* Crank up the background writer. It doesn't matter if this fails,
|
|
* we'll just try again later.
|
|
*/
|
|
Assert(BgWriterPID == 0);
|
|
BgWriterPID = StartBackgroundWriter();
|
|
|
|
pmState = PM_RECOVERY;
|
|
}
|
|
if (CheckPostmasterSignal(PMSIGNAL_RECOVERY_CONSISTENT) &&
|
|
pmState == PM_RECOVERY)
|
|
{
|
|
/*
|
|
* Likewise, start other special children as needed.
|
|
*/
|
|
Assert(PgStatPID == 0);
|
|
PgStatPID = pgstat_start();
|
|
|
|
ereport(LOG,
|
|
(errmsg("database system is ready to accept read only connections")));
|
|
|
|
pmState = PM_RECOVERY_CONSISTENT;
|
|
}
|
|
|
|
if (CheckPostmasterSignal(PMSIGNAL_WAKEN_ARCHIVER) &&
|
|
PgArchPID != 0)
|
|
{
|
|
/*
|
|
* Send SIGUSR1 to archiver process, to wake it up and begin archiving
|
|
* next transaction log file.
|
|
*/
|
|
signal_child(PgArchPID, SIGUSR1);
|
|
}
|
|
|
|
if (CheckPostmasterSignal(PMSIGNAL_ROTATE_LOGFILE) &&
|
|
SysLoggerPID != 0)
|
|
{
|
|
/* Tell syslogger to rotate logfile */
|
|
signal_child(SysLoggerPID, SIGUSR1);
|
|
}
|
|
|
|
if (CheckPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER))
|
|
{
|
|
/*
|
|
* Start one iteration of the autovacuum daemon, even if autovacuuming
|
|
* is nominally not enabled. This is so we can have an active defense
|
|
* against transaction ID wraparound. We set a flag for the main loop
|
|
* to do it rather than trying to do it here --- this is because the
|
|
* autovac process itself may send the signal, and we want to handle
|
|
* that by launching another iteration as soon as the current one
|
|
* completes.
|
|
*/
|
|
start_autovac_launcher = true;
|
|
}
|
|
|
|
if (CheckPostmasterSignal(PMSIGNAL_START_AUTOVAC_WORKER))
|
|
{
|
|
/* The autovacuum launcher wants us to start a worker process. */
|
|
StartAutovacuumWorker();
|
|
}
|
|
|
|
if (CheckPostmasterSignal(PMSIGNAL_START_WALRECEIVER) &&
|
|
WalReceiverPID == 0)
|
|
{
|
|
/* Startup Process wants us to start the walreceiver process. */
|
|
WalReceiverPID = StartWalReceiver();
|
|
}
|
|
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
/*
|
|
* Timeout or shutdown signal from postmaster while processing startup packet.
|
|
* Cleanup and exit(1).
|
|
*
|
|
* XXX: possible future improvement: try to send a message indicating
|
|
* why we are disconnecting. Problem is to be sure we don't block while
|
|
* doing so, nor mess up SSL initialization. In practice, if the client
|
|
* has wedged here, it probably couldn't do anything with the message anyway.
|
|
*/
|
|
static void
|
|
startup_die(SIGNAL_ARGS)
|
|
{
|
|
proc_exit(1);
|
|
}
|
|
|
|
/*
|
|
* Dummy signal handler
|
|
*
|
|
* We use this for signals that we don't actually use in the postmaster,
|
|
* but we do use in backends. If we were to SIG_IGN such signals in the
|
|
* postmaster, then a newly started backend might drop a signal that arrives
|
|
* before it's able to reconfigure its signal processing. (See notes in
|
|
* tcop/postgres.c.)
|
|
*/
|
|
static void
|
|
dummy_handler(SIGNAL_ARGS)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* RandomSalt
|
|
*/
|
|
static void
|
|
RandomSalt(char *md5Salt)
|
|
{
|
|
long rand;
|
|
|
|
/*
|
|
* We use % 255, sacrificing one possible byte value, so as to ensure that
|
|
* all bits of the random() value participate in the result. While at it,
|
|
* add one to avoid generating any null bytes.
|
|
*/
|
|
rand = PostmasterRandom();
|
|
md5Salt[0] = (rand % 255) + 1;
|
|
rand = PostmasterRandom();
|
|
md5Salt[1] = (rand % 255) + 1;
|
|
rand = PostmasterRandom();
|
|
md5Salt[2] = (rand % 255) + 1;
|
|
rand = PostmasterRandom();
|
|
md5Salt[3] = (rand % 255) + 1;
|
|
}
|
|
|
|
/*
|
|
* PostmasterRandom
|
|
*/
|
|
static long
|
|
PostmasterRandom(void)
|
|
{
|
|
/*
|
|
* Select a random seed at the time of first receiving a request.
|
|
*/
|
|
if (random_seed == 0)
|
|
{
|
|
do
|
|
{
|
|
struct timeval random_stop_time;
|
|
|
|
gettimeofday(&random_stop_time, NULL);
|
|
|
|
/*
|
|
* We are not sure how much precision is in tv_usec, so we swap
|
|
* the high and low 16 bits of 'random_stop_time' and XOR them
|
|
* with 'random_start_time'. On the off chance that the result is
|
|
* 0, we loop until it isn't.
|
|
*/
|
|
random_seed = random_start_time.tv_usec ^
|
|
((random_stop_time.tv_usec << 16) |
|
|
((random_stop_time.tv_usec >> 16) & 0xffff));
|
|
}
|
|
while (random_seed == 0);
|
|
|
|
srandom(random_seed);
|
|
}
|
|
|
|
return random();
|
|
}
|
|
|
|
/*
|
|
* Count up number of child processes of specified types (dead_end chidren
|
|
* are always excluded).
|
|
*/
|
|
static int
|
|
CountChildren(int target)
|
|
{
|
|
Dlelem *curr;
|
|
int cnt = 0;
|
|
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
Backend *bp = (Backend *) DLE_VAL(curr);
|
|
|
|
if (bp->dead_end)
|
|
continue;
|
|
if (!(target & BACKEND_TYPE_NORMAL) && !bp->is_autovacuum)
|
|
continue;
|
|
if (!(target & BACKEND_TYPE_AUTOVAC) && bp->is_autovacuum)
|
|
continue;
|
|
if (!(target & BACKEND_TYPE_WALSND) &&
|
|
IsPostmasterChildWalSender(bp->child_slot))
|
|
continue;
|
|
|
|
cnt++;
|
|
}
|
|
return cnt;
|
|
}
|
|
|
|
|
|
/*
|
|
* StartChildProcess -- start an auxiliary process for the postmaster
|
|
*
|
|
* xlop determines what kind of child will be started. All child types
|
|
* initially go to AuxiliaryProcessMain, which will handle common setup.
|
|
*
|
|
* Return value of StartChildProcess is subprocess' PID, or 0 if failed
|
|
* to start subprocess.
|
|
*/
|
|
static pid_t
|
|
StartChildProcess(AuxProcType type)
|
|
{
|
|
pid_t pid;
|
|
char *av[10];
|
|
int ac = 0;
|
|
char typebuf[32];
|
|
|
|
/*
|
|
* Set up command-line arguments for subprocess
|
|
*/
|
|
av[ac++] = "postgres";
|
|
|
|
#ifdef EXEC_BACKEND
|
|
av[ac++] = "--forkboot";
|
|
av[ac++] = NULL; /* filled in by postmaster_forkexec */
|
|
#endif
|
|
|
|
snprintf(typebuf, sizeof(typebuf), "-x%d", type);
|
|
av[ac++] = typebuf;
|
|
|
|
av[ac] = NULL;
|
|
Assert(ac < lengthof(av));
|
|
|
|
#ifdef EXEC_BACKEND
|
|
pid = postmaster_forkexec(ac, av);
|
|
#else /* !EXEC_BACKEND */
|
|
pid = fork_process();
|
|
|
|
if (pid == 0) /* child */
|
|
{
|
|
IsUnderPostmaster = true; /* we are a postmaster subprocess now */
|
|
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts(false);
|
|
|
|
/* Lose the postmaster's on-exit routines and port connections */
|
|
on_exit_reset();
|
|
|
|
/* Release postmaster's working memory context */
|
|
MemoryContextSwitchTo(TopMemoryContext);
|
|
MemoryContextDelete(PostmasterContext);
|
|
PostmasterContext = NULL;
|
|
|
|
AuxiliaryProcessMain(ac, av);
|
|
ExitPostmaster(0);
|
|
}
|
|
#endif /* EXEC_BACKEND */
|
|
|
|
if (pid < 0)
|
|
{
|
|
/* in parent, fork failed */
|
|
int save_errno = errno;
|
|
|
|
errno = save_errno;
|
|
switch (type)
|
|
{
|
|
case StartupProcess:
|
|
ereport(LOG,
|
|
(errmsg("could not fork startup process: %m")));
|
|
break;
|
|
case BgWriterProcess:
|
|
ereport(LOG,
|
|
(errmsg("could not fork background writer process: %m")));
|
|
break;
|
|
case WalWriterProcess:
|
|
ereport(LOG,
|
|
(errmsg("could not fork WAL writer process: %m")));
|
|
break;
|
|
case WalReceiverProcess:
|
|
ereport(LOG,
|
|
(errmsg("could not fork WAL receiver process: %m")));
|
|
break;
|
|
default:
|
|
ereport(LOG,
|
|
(errmsg("could not fork process: %m")));
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* fork failure is fatal during startup, but there's no need to choke
|
|
* immediately if starting other child types fails.
|
|
*/
|
|
if (type == StartupProcess)
|
|
ExitPostmaster(1);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* in parent, successful fork
|
|
*/
|
|
return pid;
|
|
}
|
|
|
|
/*
|
|
* StartAutovacuumWorker
|
|
* Start an autovac worker process.
|
|
*
|
|
* This function is here because it enters the resulting PID into the
|
|
* postmaster's private backends list.
|
|
*
|
|
* NB -- this code very roughly matches BackendStartup.
|
|
*/
|
|
static void
|
|
StartAutovacuumWorker(void)
|
|
{
|
|
Backend *bn;
|
|
|
|
/*
|
|
* If not in condition to run a process, don't try, but handle it like a
|
|
* fork failure. This does not normally happen, since the signal is only
|
|
* supposed to be sent by autovacuum launcher when it's OK to do it, but
|
|
* we have to check to avoid race-condition problems during DB state
|
|
* changes.
|
|
*/
|
|
if (canAcceptConnections() == CAC_OK)
|
|
{
|
|
bn = (Backend *) malloc(sizeof(Backend));
|
|
if (bn)
|
|
{
|
|
/*
|
|
* Compute the cancel key that will be assigned to this session.
|
|
* We probably don't need cancel keys for autovac workers, but
|
|
* we'd better have something random in the field to prevent
|
|
* unfriendly people from sending cancels to them.
|
|
*/
|
|
MyCancelKey = PostmasterRandom();
|
|
bn->cancel_key = MyCancelKey;
|
|
|
|
/* Autovac workers are not dead_end and need a child slot */
|
|
bn->dead_end = false;
|
|
bn->child_slot = MyPMChildSlot = AssignPostmasterChildSlot();
|
|
|
|
bn->pid = StartAutoVacWorker();
|
|
if (bn->pid > 0)
|
|
{
|
|
bn->is_autovacuum = true;
|
|
DLInitElem(&bn->elem, bn);
|
|
DLAddHead(BackendList, &bn->elem);
|
|
#ifdef EXEC_BACKEND
|
|
ShmemBackendArrayAdd(bn);
|
|
#endif
|
|
/* all OK */
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* fork failed, fall through to report -- actual error message was
|
|
* logged by StartAutoVacWorker
|
|
*/
|
|
(void) ReleasePostmasterChildSlot(bn->child_slot);
|
|
free(bn);
|
|
}
|
|
else
|
|
ereport(LOG,
|
|
(errcode(ERRCODE_OUT_OF_MEMORY),
|
|
errmsg("out of memory")));
|
|
}
|
|
|
|
/*
|
|
* Report the failure to the launcher, if it's running. (If it's not, we
|
|
* might not even be connected to shared memory, so don't try to call
|
|
* AutoVacWorkerFailed.) Note that we also need to signal it so that it
|
|
* responds to the condition, but we don't do that here, instead waiting
|
|
* for ServerLoop to do it. This way we avoid a ping-pong signalling in
|
|
* quick succession between the autovac launcher and postmaster in case
|
|
* things get ugly.
|
|
*/
|
|
if (AutoVacPID != 0)
|
|
{
|
|
AutoVacWorkerFailed();
|
|
avlauncher_needs_signal = true;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Create the opts file
|
|
*/
|
|
static bool
|
|
CreateOptsFile(int argc, char *argv[], char *fullprogname)
|
|
{
|
|
FILE *fp;
|
|
int i;
|
|
|
|
#define OPTS_FILE "postmaster.opts"
|
|
|
|
if ((fp = fopen(OPTS_FILE, "w")) == NULL)
|
|
{
|
|
elog(LOG, "could not create file \"%s\": %m", OPTS_FILE);
|
|
return false;
|
|
}
|
|
|
|
fprintf(fp, "%s", fullprogname);
|
|
for (i = 1; i < argc; i++)
|
|
fprintf(fp, " \"%s\"", argv[i]);
|
|
fputs("\n", fp);
|
|
|
|
if (fclose(fp))
|
|
{
|
|
elog(LOG, "could not write file \"%s\": %m", OPTS_FILE);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
/*
|
|
* MaxLivePostmasterChildren
|
|
*
|
|
* This reports the number of entries needed in per-child-process arrays
|
|
* (the PMChildFlags array, and if EXEC_BACKEND the ShmemBackendArray).
|
|
* These arrays include regular backends, autovac workers and walsenders,
|
|
* but not special children nor dead_end children. This allows the arrays
|
|
* to have a fixed maximum size, to wit the same too-many-children limit
|
|
* enforced by canAcceptConnections(). The exact value isn't too critical
|
|
* as long as it's more than MaxBackends.
|
|
*/
|
|
int
|
|
MaxLivePostmasterChildren(void)
|
|
{
|
|
return 2 * MaxBackends;
|
|
}
|
|
|
|
|
|
#ifdef EXEC_BACKEND
|
|
|
|
/*
|
|
* The following need to be available to the save/restore_backend_variables
|
|
* functions
|
|
*/
|
|
extern slock_t *ShmemLock;
|
|
extern LWLock *LWLockArray;
|
|
extern slock_t *ProcStructLock;
|
|
extern PROC_HDR *ProcGlobal;
|
|
extern PGPROC *AuxiliaryProcs;
|
|
extern PMSignalData *PMSignalState;
|
|
extern pgsocket pgStatSock;
|
|
|
|
#ifndef WIN32
|
|
#define write_inheritable_socket(dest, src, childpid) ((*(dest) = (src)), true)
|
|
#define read_inheritable_socket(dest, src) (*(dest) = *(src))
|
|
#else
|
|
static bool write_duplicated_handle(HANDLE *dest, HANDLE src, HANDLE child);
|
|
static bool write_inheritable_socket(InheritableSocket *dest, SOCKET src,
|
|
pid_t childPid);
|
|
static void read_inheritable_socket(SOCKET *dest, InheritableSocket *src);
|
|
#endif
|
|
|
|
|
|
/* Save critical backend variables into the BackendParameters struct */
|
|
#ifndef WIN32
|
|
static bool
|
|
save_backend_variables(BackendParameters *param, Port *port)
|
|
#else
|
|
static bool
|
|
save_backend_variables(BackendParameters *param, Port *port,
|
|
HANDLE childProcess, pid_t childPid)
|
|
#endif
|
|
{
|
|
memcpy(¶m->port, port, sizeof(Port));
|
|
if (!write_inheritable_socket(¶m->portsocket, port->sock, childPid))
|
|
return false;
|
|
|
|
strlcpy(param->DataDir, DataDir, MAXPGPATH);
|
|
|
|
memcpy(¶m->ListenSocket, &ListenSocket, sizeof(ListenSocket));
|
|
|
|
param->MyCancelKey = MyCancelKey;
|
|
param->MyPMChildSlot = MyPMChildSlot;
|
|
|
|
param->UsedShmemSegID = UsedShmemSegID;
|
|
param->UsedShmemSegAddr = UsedShmemSegAddr;
|
|
|
|
param->ShmemLock = ShmemLock;
|
|
param->ShmemVariableCache = ShmemVariableCache;
|
|
param->ShmemBackendArray = ShmemBackendArray;
|
|
|
|
param->LWLockArray = LWLockArray;
|
|
param->ProcStructLock = ProcStructLock;
|
|
param->ProcGlobal = ProcGlobal;
|
|
param->AuxiliaryProcs = AuxiliaryProcs;
|
|
param->PMSignalState = PMSignalState;
|
|
if (!write_inheritable_socket(¶m->pgStatSock, pgStatSock, childPid))
|
|
return false;
|
|
|
|
param->PostmasterPid = PostmasterPid;
|
|
param->PgStartTime = PgStartTime;
|
|
param->PgReloadTime = PgReloadTime;
|
|
|
|
param->redirection_done = redirection_done;
|
|
|
|
#ifdef WIN32
|
|
param->PostmasterHandle = PostmasterHandle;
|
|
if (!write_duplicated_handle(¶m->initial_signal_pipe,
|
|
pgwin32_create_signal_listener(childPid),
|
|
childProcess))
|
|
return false;
|
|
#endif
|
|
|
|
memcpy(¶m->syslogPipe, &syslogPipe, sizeof(syslogPipe));
|
|
|
|
strlcpy(param->my_exec_path, my_exec_path, MAXPGPATH);
|
|
|
|
strlcpy(param->pkglib_path, pkglib_path, MAXPGPATH);
|
|
|
|
strlcpy(param->ExtraOptions, ExtraOptions, MAXPGPATH);
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
#ifdef WIN32
|
|
/*
|
|
* Duplicate a handle for usage in a child process, and write the child
|
|
* process instance of the handle to the parameter file.
|
|
*/
|
|
static bool
|
|
write_duplicated_handle(HANDLE *dest, HANDLE src, HANDLE childProcess)
|
|
{
|
|
HANDLE hChild = INVALID_HANDLE_VALUE;
|
|
|
|
if (!DuplicateHandle(GetCurrentProcess(),
|
|
src,
|
|
childProcess,
|
|
&hChild,
|
|
0,
|
|
TRUE,
|
|
DUPLICATE_CLOSE_SOURCE | DUPLICATE_SAME_ACCESS))
|
|
{
|
|
ereport(LOG,
|
|
(errmsg_internal("could not duplicate handle to be written to backend parameter file: error code %d",
|
|
(int) GetLastError())));
|
|
return false;
|
|
}
|
|
|
|
*dest = hChild;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Duplicate a socket for usage in a child process, and write the resulting
|
|
* structure to the parameter file.
|
|
* This is required because a number of LSPs (Layered Service Providers) very
|
|
* common on Windows (antivirus, firewalls, download managers etc) break
|
|
* straight socket inheritance.
|
|
*/
|
|
static bool
|
|
write_inheritable_socket(InheritableSocket *dest, SOCKET src, pid_t childpid)
|
|
{
|
|
dest->origsocket = src;
|
|
if (src != 0 && src != PGINVALID_SOCKET)
|
|
{
|
|
/* Actual socket */
|
|
if (WSADuplicateSocket(src, childpid, &dest->wsainfo) != 0)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("could not duplicate socket %d for use in backend: error code %d",
|
|
src, WSAGetLastError())));
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Read a duplicate socket structure back, and get the socket descriptor.
|
|
*/
|
|
static void
|
|
read_inheritable_socket(SOCKET *dest, InheritableSocket *src)
|
|
{
|
|
SOCKET s;
|
|
|
|
if (src->origsocket == PGINVALID_SOCKET || src->origsocket == 0)
|
|
{
|
|
/* Not a real socket! */
|
|
*dest = src->origsocket;
|
|
}
|
|
else
|
|
{
|
|
/* Actual socket, so create from structure */
|
|
s = WSASocket(FROM_PROTOCOL_INFO,
|
|
FROM_PROTOCOL_INFO,
|
|
FROM_PROTOCOL_INFO,
|
|
&src->wsainfo,
|
|
0,
|
|
0);
|
|
if (s == INVALID_SOCKET)
|
|
{
|
|
write_stderr("could not create inherited socket: error code %d\n",
|
|
WSAGetLastError());
|
|
exit(1);
|
|
}
|
|
*dest = s;
|
|
|
|
/*
|
|
* To make sure we don't get two references to the same socket, close
|
|
* the original one. (This would happen when inheritance actually
|
|
* works..
|
|
*/
|
|
closesocket(src->origsocket);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
static void
|
|
read_backend_variables(char *id, Port *port)
|
|
{
|
|
BackendParameters param;
|
|
|
|
#ifndef WIN32
|
|
/* Non-win32 implementation reads from file */
|
|
FILE *fp;
|
|
|
|
/* Open file */
|
|
fp = AllocateFile(id, PG_BINARY_R);
|
|
if (!fp)
|
|
{
|
|
write_stderr("could not read from backend variables file \"%s\": %s\n",
|
|
id, strerror(errno));
|
|
exit(1);
|
|
}
|
|
|
|
if (fread(¶m, sizeof(param), 1, fp) != 1)
|
|
{
|
|
write_stderr("could not read from backend variables file \"%s\": %s\n",
|
|
id, strerror(errno));
|
|
exit(1);
|
|
}
|
|
|
|
/* Release file */
|
|
FreeFile(fp);
|
|
if (unlink(id) != 0)
|
|
{
|
|
write_stderr("could not remove file \"%s\": %s\n",
|
|
id, strerror(errno));
|
|
exit(1);
|
|
}
|
|
#else
|
|
/* Win32 version uses mapped file */
|
|
HANDLE paramHandle;
|
|
BackendParameters *paramp;
|
|
|
|
paramHandle = (HANDLE) atol(id);
|
|
paramp = MapViewOfFile(paramHandle, FILE_MAP_READ, 0, 0, 0);
|
|
if (!paramp)
|
|
{
|
|
write_stderr("could not map view of backend variables: error code %d\n",
|
|
(int) GetLastError());
|
|
exit(1);
|
|
}
|
|
|
|
memcpy(¶m, paramp, sizeof(BackendParameters));
|
|
|
|
if (!UnmapViewOfFile(paramp))
|
|
{
|
|
write_stderr("could not unmap view of backend variables: error code %d\n",
|
|
(int) GetLastError());
|
|
exit(1);
|
|
}
|
|
|
|
if (!CloseHandle(paramHandle))
|
|
{
|
|
write_stderr("could not close handle to backend parameter variables: error code %d\n",
|
|
(int) GetLastError());
|
|
exit(1);
|
|
}
|
|
#endif
|
|
|
|
restore_backend_variables(¶m, port);
|
|
}
|
|
|
|
/* Restore critical backend variables from the BackendParameters struct */
|
|
static void
|
|
restore_backend_variables(BackendParameters *param, Port *port)
|
|
{
|
|
memcpy(port, ¶m->port, sizeof(Port));
|
|
read_inheritable_socket(&port->sock, ¶m->portsocket);
|
|
|
|
SetDataDir(param->DataDir);
|
|
|
|
memcpy(&ListenSocket, ¶m->ListenSocket, sizeof(ListenSocket));
|
|
|
|
MyCancelKey = param->MyCancelKey;
|
|
MyPMChildSlot = param->MyPMChildSlot;
|
|
|
|
UsedShmemSegID = param->UsedShmemSegID;
|
|
UsedShmemSegAddr = param->UsedShmemSegAddr;
|
|
|
|
ShmemLock = param->ShmemLock;
|
|
ShmemVariableCache = param->ShmemVariableCache;
|
|
ShmemBackendArray = param->ShmemBackendArray;
|
|
|
|
LWLockArray = param->LWLockArray;
|
|
ProcStructLock = param->ProcStructLock;
|
|
ProcGlobal = param->ProcGlobal;
|
|
AuxiliaryProcs = param->AuxiliaryProcs;
|
|
PMSignalState = param->PMSignalState;
|
|
read_inheritable_socket(&pgStatSock, ¶m->pgStatSock);
|
|
|
|
PostmasterPid = param->PostmasterPid;
|
|
PgStartTime = param->PgStartTime;
|
|
PgReloadTime = param->PgReloadTime;
|
|
|
|
redirection_done = param->redirection_done;
|
|
|
|
#ifdef WIN32
|
|
PostmasterHandle = param->PostmasterHandle;
|
|
pgwin32_initial_signal_pipe = param->initial_signal_pipe;
|
|
#endif
|
|
|
|
memcpy(&syslogPipe, ¶m->syslogPipe, sizeof(syslogPipe));
|
|
|
|
strlcpy(my_exec_path, param->my_exec_path, MAXPGPATH);
|
|
|
|
strlcpy(pkglib_path, param->pkglib_path, MAXPGPATH);
|
|
|
|
strlcpy(ExtraOptions, param->ExtraOptions, MAXPGPATH);
|
|
}
|
|
|
|
|
|
Size
|
|
ShmemBackendArraySize(void)
|
|
{
|
|
return mul_size(MaxLivePostmasterChildren(), sizeof(Backend));
|
|
}
|
|
|
|
void
|
|
ShmemBackendArrayAllocation(void)
|
|
{
|
|
Size size = ShmemBackendArraySize();
|
|
|
|
ShmemBackendArray = (Backend *) ShmemAlloc(size);
|
|
/* Mark all slots as empty */
|
|
memset(ShmemBackendArray, 0, size);
|
|
}
|
|
|
|
static void
|
|
ShmemBackendArrayAdd(Backend *bn)
|
|
{
|
|
/* The array slot corresponding to my PMChildSlot should be free */
|
|
int i = bn->child_slot - 1;
|
|
|
|
Assert(ShmemBackendArray[i].pid == 0);
|
|
ShmemBackendArray[i] = *bn;
|
|
}
|
|
|
|
static void
|
|
ShmemBackendArrayRemove(Backend *bn)
|
|
{
|
|
int i = bn->child_slot - 1;
|
|
|
|
Assert(ShmemBackendArray[i].pid == bn->pid);
|
|
/* Mark the slot as empty */
|
|
ShmemBackendArray[i].pid = 0;
|
|
}
|
|
#endif /* EXEC_BACKEND */
|
|
|
|
|
|
#ifdef WIN32
|
|
|
|
static pid_t
|
|
win32_waitpid(int *exitstatus)
|
|
{
|
|
DWORD dwd;
|
|
ULONG_PTR key;
|
|
OVERLAPPED *ovl;
|
|
|
|
/*
|
|
* Check if there are any dead children. If there are, return the pid of
|
|
* the first one that died.
|
|
*/
|
|
if (GetQueuedCompletionStatus(win32ChildQueue, &dwd, &key, &ovl, 0))
|
|
{
|
|
*exitstatus = (int) key;
|
|
return dwd;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Note! Code below executes on a thread pool! All operations must
|
|
* be thread safe! Note that elog() and friends must *not* be used.
|
|
*/
|
|
static void WINAPI
|
|
pgwin32_deadchild_callback(PVOID lpParameter, BOOLEAN TimerOrWaitFired)
|
|
{
|
|
win32_deadchild_waitinfo *childinfo = (win32_deadchild_waitinfo *) lpParameter;
|
|
DWORD exitcode;
|
|
|
|
if (TimerOrWaitFired)
|
|
return; /* timeout. Should never happen, since we use
|
|
* INFINITE as timeout value. */
|
|
|
|
/*
|
|
* Remove handle from wait - required even though it's set to wait only
|
|
* once
|
|
*/
|
|
UnregisterWaitEx(childinfo->waitHandle, NULL);
|
|
|
|
if (!GetExitCodeProcess(childinfo->procHandle, &exitcode))
|
|
{
|
|
/*
|
|
* Should never happen. Inform user and set a fixed exitcode.
|
|
*/
|
|
write_stderr("could not read exit code for process\n");
|
|
exitcode = 255;
|
|
}
|
|
|
|
if (!PostQueuedCompletionStatus(win32ChildQueue, childinfo->procId, (ULONG_PTR) exitcode, NULL))
|
|
write_stderr("could not post child completion status\n");
|
|
|
|
/*
|
|
* Handle is per-process, so we close it here instead of in the
|
|
* originating thread
|
|
*/
|
|
CloseHandle(childinfo->procHandle);
|
|
|
|
/*
|
|
* Free struct that was allocated before the call to
|
|
* RegisterWaitForSingleObject()
|
|
*/
|
|
free(childinfo);
|
|
|
|
/* Queue SIGCHLD signal */
|
|
pg_queue_signal(SIGCHLD);
|
|
}
|
|
|
|
#endif /* WIN32 */
|