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routine to do something appropriate on Win32. Also, add a security check on Win32 that parallels the can't-run-as-root check on Unix. Magnus Hagander
3600 lines
89 KiB
C
3600 lines
89 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) 1996-2003, 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 1.405 2004/06/24 21:02:55 tgl 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 <errno.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_RENDEZVOUS
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#include <DNSServiceDiscovery/DNSServiceDiscovery.h>
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#endif
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#include "catalog/pg_database.h"
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#include "commands/async.h"
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#include "lib/dllist.h"
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#include "libpq/auth.h"
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#include "libpq/crypt.h"
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#include "libpq/libpq.h"
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#include "libpq/pqcomm.h"
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#include "libpq/pqsignal.h"
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#include "miscadmin.h"
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#include "nodes/nodes.h"
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#include "postmaster/postmaster.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 "storage/bufmgr.h"
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#include "access/xlog.h"
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#include "tcop/tcopprot.h"
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#include "utils/guc.h"
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#include "utils/memutils.h"
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#include "utils/ps_status.h"
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#include "bootstrap/bootstrap.h"
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#include "pgstat.h"
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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 and bgwriter tasks are not in
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* this list.
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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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} Backend;
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static Dllist *BackendList;
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#ifdef EXEC_BACKEND
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#define NUM_BACKENDARRAY_ELEMS (2*MaxBackends)
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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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static const char *progname = NULL;
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/* The socket(s) we're listening to. */
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#define MAXLISTEN 10
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static int 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.
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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 (-S) */
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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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char *rendezvous_name;
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/* list of library:init-function to be preloaded */
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char *preload_libraries_string = NULL;
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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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PgStatPID = 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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bool ClientAuthInProgress = false; /* T during new-client
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* authentication */
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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 int debug_flag = 0;
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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;
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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 checkDataDir(const char *checkdir);
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#ifdef USE_RENDEZVOUS
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static void reg_reply(DNSServiceRegistrationReplyErrorType errorCode,
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void *context);
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#endif
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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(unsigned short 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 dummy_handler(SIGNAL_ARGS);
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static void CleanupProc(int pid, int exitstatus);
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static void HandleChildCrash(int pid, int exitstatus);
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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 int BackendRun(Port *port);
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static void ExitPostmaster(int status);
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static void usage(const char *);
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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 *cryptSalt, char *md5Salt);
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static void SignalChildren(int signal);
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static int CountChildren(void);
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static bool CreateOptsFile(int argc, char *argv[], char *fullprogname);
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static pid_t StartChildProcess(int xlop);
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#ifdef EXEC_BACKEND
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#ifdef WIN32
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static pid_t win32_forkexec(const char *path, char *argv[]);
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static void win32_AddChild(pid_t pid, HANDLE handle);
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static void win32_RemoveChild(pid_t pid);
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static pid_t win32_waitpid(int *exitstatus);
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static DWORD WINAPI win32_sigchld_waiter(LPVOID param);
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static pid_t *win32_childPIDArray;
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static HANDLE *win32_childHNDArray;
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static unsigned long win32_numChildren = 0;
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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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static void read_backend_variables(char *filename, Port *port);
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static bool write_backend_variables(char *filename, Port *port);
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static void ShmemBackendArrayAdd(Backend *bn);
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static void ShmemBackendArrayRemove(pid_t pid);
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#endif /* EXEC_BACKEND */
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#define StartupDataBase() StartChildProcess(BS_XLOG_STARTUP)
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#define StartBackgroundWriter() StartChildProcess(BS_XLOG_BGWRITER)
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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 *potential_DataDir = NULL;
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int i;
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progname = get_progname(argv[0]);
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MyProcPid = PostmasterPid = getpid();
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IsPostmasterEnvironment = true;
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/*
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* Catch standard options before doing much else. This even works on
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* systems without getopt_long.
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*/
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if (argc > 1)
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{
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if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
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{
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usage(progname);
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ExitPostmaster(0);
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}
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if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
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{
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puts("postmaster (PostgreSQL) " PG_VERSION);
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ExitPostmaster(0);
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}
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}
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/*
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* for security, no dir or file created can be group or other
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* accessible
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*/
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umask((mode_t) 0077);
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/*
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* Fire up essential subsystems: memory management
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*/
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MemoryContextInit();
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/*
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* By default, palloc() requests in the postmaster will be allocated
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* in the PostmasterContext, which is space that can be recycled by
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* backends. Allocated data that needs to be available to backends
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* should be allocated in TopMemoryContext.
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*/
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PostmasterContext = AllocSetContextCreate(TopMemoryContext,
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"Postmaster",
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ALLOCSET_DEFAULT_MINSIZE,
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ALLOCSET_DEFAULT_INITSIZE,
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ALLOCSET_DEFAULT_MAXSIZE);
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MemoryContextSwitchTo(PostmasterContext);
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IgnoreSystemIndexes(false);
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if (find_my_exec(argv[0], my_exec_path) < 0)
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elog(FATAL, "%s: could not locate my own executable path",
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argv[0]);
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get_pkglib_path(my_exec_path, pkglib_path);
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/*
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* Options setup
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*/
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InitializeGUCOptions();
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potential_DataDir = getenv("PGDATA"); /* default value */
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opterr = 1;
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while ((opt = getopt(argc, argv, "A:a:B:b:c:D:d:Fh:ik:lm:MN:no:p:Ss-:")) != -1)
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{
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switch (opt)
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{
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case 'A':
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#ifdef USE_ASSERT_CHECKING
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SetConfigOption("debug_assertions", optarg, PGC_POSTMASTER, PGC_S_ARGV);
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#else
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write_stderr("%s: assert checking is not compiled in\n", progname);
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#endif
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break;
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case 'a':
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/* Can no longer set authentication method. */
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break;
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case 'B':
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SetConfigOption("shared_buffers", optarg, PGC_POSTMASTER, PGC_S_ARGV);
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break;
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case 'b':
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/* Can no longer set the backend executable file to use. */
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break;
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case 'D':
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potential_DataDir = optarg;
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break;
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case 'd':
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{
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/* Turn on debugging for the postmaster. */
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char *debugstr = palloc(strlen("debug") + strlen(optarg) + 1);
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sprintf(debugstr, "debug%s", optarg);
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SetConfigOption("log_min_messages", debugstr,
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PGC_POSTMASTER, PGC_S_ARGV);
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pfree(debugstr);
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debug_flag = atoi(optarg);
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break;
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}
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case 'F':
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SetConfigOption("fsync", "false", PGC_POSTMASTER, PGC_S_ARGV);
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break;
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case 'h':
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SetConfigOption("listen_addresses", optarg, PGC_POSTMASTER, PGC_S_ARGV);
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break;
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case 'i':
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SetConfigOption("listen_addresses", "*", PGC_POSTMASTER, PGC_S_ARGV);
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break;
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case 'k':
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SetConfigOption("unix_socket_directory", optarg, PGC_POSTMASTER, PGC_S_ARGV);
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break;
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#ifdef USE_SSL
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case 'l':
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SetConfigOption("ssl", "true", PGC_POSTMASTER, PGC_S_ARGV);
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break;
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#endif
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case 'm':
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/* Multiplexed backends no longer supported. */
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break;
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case 'M':
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/*
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* ignore this flag. This may be passed in because the
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* program was run as 'postgres -M' instead of
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* 'postmaster'
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*/
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break;
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case 'N':
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/* The max number of backends to start. */
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SetConfigOption("max_connections", optarg, PGC_POSTMASTER, PGC_S_ARGV);
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break;
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case 'n':
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/* Don't reinit shared mem after abnormal exit */
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Reinit = false;
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break;
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case 'o':
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|
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|
/*
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* Other options to pass to the backend on the command line
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*/
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strcat(ExtraOptions, " ");
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strcat(ExtraOptions, optarg);
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break;
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case 'p':
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SetConfigOption("port", optarg, PGC_POSTMASTER, PGC_S_ARGV);
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break;
|
|
case 'S':
|
|
|
|
/*
|
|
* Start in 'S'ilent mode (disassociate from controlling
|
|
* tty). You may also think of this as 'S'ysV mode since
|
|
* it's most badly needed on SysV-derived systems like
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* SVR4 and HP-UX.
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|
*/
|
|
SetConfigOption("silent_mode", "true", PGC_POSTMASTER, PGC_S_ARGV);
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break;
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|
case 's':
|
|
|
|
/*
|
|
* 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
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|
* everyone.
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|
*/
|
|
SendStop = true;
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|
break;
|
|
case 'c':
|
|
case '-':
|
|
{
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|
char *name,
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|
*value;
|
|
|
|
ParseLongOption(optarg, &name, &value);
|
|
if (!value)
|
|
{
|
|
if (opt == '-')
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|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("--%s requires a value",
|
|
optarg)));
|
|
else
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
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|
errmsg("-c %s requires a value",
|
|
optarg)));
|
|
}
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|
|
SetConfigOption(name, value, PGC_POSTMASTER, PGC_S_ARGV);
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free(name);
|
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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);
|
|
}
|
|
|
|
/*
|
|
* Now we can set the data directory, and then read postgresql.conf.
|
|
*/
|
|
checkDataDir(potential_DataDir); /* issues error messages */
|
|
SetDataDir(potential_DataDir);
|
|
|
|
ProcessConfigFile(PGC_POSTMASTER);
|
|
|
|
/* If timezone is not set, determine what the OS uses */
|
|
pg_timezone_initialize();
|
|
|
|
#ifdef EXEC_BACKEND
|
|
write_nondefault_variables(PGC_POSTMASTER);
|
|
#endif
|
|
|
|
/*
|
|
* Check for invalid combinations of GUC settings.
|
|
*/
|
|
if (NBuffers < 2 * MaxBackends || NBuffers < 16)
|
|
{
|
|
/*
|
|
* Do not accept -B so small that backends are likely to starve
|
|
* for lack of buffers. The specific choices here are somewhat
|
|
* arbitrary.
|
|
*/
|
|
write_stderr("%s: the number of buffers (-B) must be at least twice the number of allowed connections (-N) and at least 16\n", progname);
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
if (ReservedBackends >= MaxBackends)
|
|
{
|
|
write_stderr("%s: superuser_reserved_connections must be less than max_connections\n", progname);
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
/*
|
|
* Other one-time internal sanity checks can go here.
|
|
*/
|
|
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("-----------------------------------------")));
|
|
}
|
|
|
|
#ifdef EXEC_BACKEND
|
|
if (find_other_exec(argv[0], "postgres", PG_VERSIONSTR,
|
|
postgres_exec_path) < 0)
|
|
ereport(FATAL,
|
|
(errmsg("%s: could not locate matching postgres executable",
|
|
progname)));
|
|
#endif
|
|
|
|
/*
|
|
* Initialize SSL library, if specified.
|
|
*/
|
|
#ifdef USE_SSL
|
|
if (EnableSSL)
|
|
secure_initialize();
|
|
#endif
|
|
|
|
/*
|
|
* process any libraries that should be preloaded and optionally
|
|
* pre-initialized
|
|
*/
|
|
if (preload_libraries_string)
|
|
process_preload_libraries(preload_libraries_string);
|
|
|
|
/*
|
|
* Fork away from controlling terminal, if -S 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(DataDir, true);
|
|
|
|
/*
|
|
* 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] = -1;
|
|
|
|
if (ListenAddresses)
|
|
{
|
|
char *curhost,
|
|
*endptr;
|
|
char c;
|
|
|
|
curhost = ListenAddresses;
|
|
for (;;)
|
|
{
|
|
/* ignore whitespace */
|
|
while (isspace((unsigned char) *curhost))
|
|
curhost++;
|
|
if (*curhost == '\0')
|
|
break;
|
|
endptr = curhost;
|
|
while (*endptr != '\0' && !isspace((unsigned char) *endptr))
|
|
endptr++;
|
|
c = *endptr;
|
|
*endptr = '\0';
|
|
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)
|
|
ereport(WARNING,
|
|
(errmsg("could not create listen socket for \"%s\"",
|
|
curhost)));
|
|
*endptr = c;
|
|
if (c != '\0')
|
|
curhost = endptr + 1;
|
|
else
|
|
break;
|
|
}
|
|
}
|
|
|
|
#ifdef USE_RENDEZVOUS
|
|
/* Register for Rendezvous only if we opened TCP socket(s) */
|
|
if (ListenSocket[0] != -1 && rendezvous_name != NULL)
|
|
{
|
|
DNSServiceRegistrationCreate(rendezvous_name,
|
|
"_postgresql._tcp.",
|
|
"",
|
|
htonl(PostPortNumber),
|
|
"",
|
|
(DNSServiceRegistrationReply) reg_reply,
|
|
NULL);
|
|
}
|
|
#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] == -1)
|
|
ereport(FATAL,
|
|
(errmsg("no socket created for listening")));
|
|
|
|
XLOGPathInit();
|
|
|
|
/*
|
|
* 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 the child pid/HANDLE arrays for signal handling.
|
|
*/
|
|
win32_childPIDArray = (pid_t *)
|
|
malloc(NUM_BACKENDARRAY_ELEMS * sizeof(pid_t));
|
|
win32_childHNDArray = (HANDLE *)
|
|
malloc(NUM_BACKENDARRAY_ELEMS * sizeof(HANDLE));
|
|
if (!win32_childPIDArray || !win32_childHNDArray)
|
|
ereport(FATAL,
|
|
(errcode(ERRCODE_OUT_OF_MEMORY),
|
|
errmsg("out of memory")));
|
|
|
|
/*
|
|
* 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: %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);
|
|
|
|
/*
|
|
* 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, and postmaster/pgstat.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
|
|
|
|
/*
|
|
* Reset whereToSendOutput from Debug (its starting state) to None.
|
|
* This prevents ereport from sending log messages to stderr unless
|
|
* the syslog/stderr switch permits. We don't do this until the
|
|
* postmaster is fully launched, since startup failures may as well be
|
|
* reported to stderr.
|
|
*/
|
|
whereToSendOutput = None;
|
|
|
|
/*
|
|
* Initialize the statistics collector stuff
|
|
*/
|
|
pgstat_init();
|
|
|
|
/*
|
|
* Load cached files for client authentication.
|
|
*/
|
|
load_hba();
|
|
load_ident();
|
|
load_user();
|
|
load_group();
|
|
|
|
/*
|
|
* We're ready to rock and roll...
|
|
*/
|
|
StartupPID = StartupDataBase();
|
|
|
|
#ifdef EXEC_BACKEND
|
|
write_nondefault_variables(PGC_POSTMASTER);
|
|
#endif
|
|
|
|
status = ServerLoop();
|
|
|
|
/*
|
|
* ServerLoop probably shouldn't ever return, but if it does, close
|
|
* down.
|
|
*/
|
|
ExitPostmaster(status != STATUS_OK);
|
|
|
|
return 0; /* not reached */
|
|
}
|
|
|
|
|
|
/*
|
|
* Validate the proposed data directory
|
|
*/
|
|
static void
|
|
checkDataDir(const char *checkdir)
|
|
{
|
|
char path[MAXPGPATH];
|
|
FILE *fp;
|
|
struct stat stat_buf;
|
|
|
|
if (checkdir == NULL)
|
|
{
|
|
write_stderr("%s does not know where to find the database system data.\n"
|
|
"You must specify the directory that contains the database system\n"
|
|
"either by specifying the -D invocation option or by setting the\n"
|
|
"PGDATA environment variable.\n",
|
|
progname);
|
|
ExitPostmaster(2);
|
|
}
|
|
|
|
if (stat(checkdir, &stat_buf) == -1)
|
|
{
|
|
if (errno == ENOENT)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("data directory \"%s\" does not exist",
|
|
checkdir)));
|
|
else
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read permissions of directory \"%s\": %m",
|
|
checkdir)));
|
|
}
|
|
|
|
/*
|
|
* Check if the directory has group or world access. If so, reject.
|
|
*
|
|
* 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(__CYGWIN__) && !defined(WIN32)
|
|
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",
|
|
checkdir),
|
|
errdetail("Permissions should be u=rwx (0700).")));
|
|
#endif
|
|
|
|
/* Look for PG_VERSION before looking for pg_control */
|
|
ValidatePgVersion(checkdir);
|
|
|
|
snprintf(path, sizeof(path), "%s/global/pg_control", checkdir);
|
|
|
|
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, checkdir, path, strerror(errno));
|
|
ExitPostmaster(2);
|
|
}
|
|
FreeFile(fp);
|
|
}
|
|
|
|
|
|
#ifdef USE_RENDEZVOUS
|
|
|
|
/*
|
|
* empty callback function for DNSServiceRegistrationCreate()
|
|
*/
|
|
static void
|
|
reg_reply(DNSServiceRegistrationReplyErrorType errorCode, void *context)
|
|
{
|
|
|
|
}
|
|
|
|
#endif /* USE_RENDEZVOUS */
|
|
|
|
|
|
/*
|
|
* Fork away from the controlling terminal (-S option)
|
|
*/
|
|
static void
|
|
pmdaemonize(void)
|
|
{
|
|
#ifndef WIN32
|
|
int i;
|
|
pid_t pid;
|
|
|
|
#ifdef LINUX_PROFILE
|
|
struct itimerval prof_itimer;
|
|
#endif
|
|
|
|
#ifdef LINUX_PROFILE
|
|
/* see comments in BackendStartup */
|
|
getitimer(ITIMER_PROF, &prof_itimer);
|
|
#endif
|
|
|
|
pid = fork();
|
|
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);
|
|
}
|
|
|
|
#ifdef LINUX_PROFILE
|
|
setitimer(ITIMER_PROF, &prof_itimer, NULL);
|
|
#endif
|
|
|
|
MyProcPid = PostmasterPid = getpid(); /* reset PID vars to child */
|
|
|
|
/* GH: If there's no setsid(), we hopefully don't need silent mode.
|
|
* Until there's a better solution.
|
|
*/
|
|
#ifdef HAVE_SETSID
|
|
if (setsid() < 0)
|
|
{
|
|
write_stderr("%s: could not dissociate from controlling TTY: %s\n",
|
|
progname, strerror(errno));
|
|
ExitPostmaster(1);
|
|
}
|
|
#endif
|
|
i = open(NULL_DEV, O_RDWR | PG_BINARY);
|
|
dup2(i, 0);
|
|
dup2(i, 1);
|
|
dup2(i, 2);
|
|
close(i);
|
|
#else /* WIN32 */
|
|
/* not supported */
|
|
elog(FATAL, "SilentMode not supported under WIN32");
|
|
#endif /* WIN32 */
|
|
}
|
|
|
|
|
|
/*
|
|
* Print out help message
|
|
*/
|
|
static void
|
|
usage(const char *progname)
|
|
{
|
|
printf(gettext("%s is the PostgreSQL server.\n\n"), progname);
|
|
printf(gettext("Usage:\n %s [OPTION]...\n\n"), progname);
|
|
printf(gettext("Options:\n"));
|
|
#ifdef USE_ASSERT_CHECKING
|
|
printf(gettext(" -A 1|0 enable/disable run-time assert checking\n"));
|
|
#endif
|
|
printf(gettext(" -B NBUFFERS number of shared buffers\n"));
|
|
printf(gettext(" -c NAME=VALUE set run-time parameter\n"));
|
|
printf(gettext(" -d 1-5 debugging level\n"));
|
|
printf(gettext(" -D DATADIR database directory\n"));
|
|
printf(gettext(" -F turn fsync off\n"));
|
|
printf(gettext(" -h HOSTNAME host name or IP address to listen on\n"));
|
|
printf(gettext(" -i enable TCP/IP connections\n"));
|
|
printf(gettext(" -k DIRECTORY Unix-domain socket location\n"));
|
|
#ifdef USE_SSL
|
|
printf(gettext(" -l enable SSL connections\n"));
|
|
#endif
|
|
printf(gettext(" -N MAX-CONNECT maximum number of allowed connections\n"));
|
|
printf(gettext(" -o OPTIONS pass \"OPTIONS\" to each server process\n"));
|
|
printf(gettext(" -p PORT port number to listen on\n"));
|
|
printf(gettext(" -S silent mode (start in background without logging output)\n"));
|
|
printf(gettext(" --help show this help, then exit\n"));
|
|
printf(gettext(" --version output version information, then exit\n"));
|
|
|
|
printf(gettext("\nDeveloper options:\n"));
|
|
printf(gettext(" -n do not reinitialize shared memory after abnormal exit\n"));
|
|
printf(gettext(" -s send SIGSTOP to all backend servers if one dies\n"));
|
|
|
|
printf(gettext("\nPlease read the documentation for the complete list of run-time\n"
|
|
"configuration settings and how to set them on the command line or in\n"
|
|
"the configuration file.\n\n"
|
|
"Report bugs to <pgsql-bugs@postgresql.org>.\n"));
|
|
}
|
|
|
|
|
|
/*
|
|
* Main idle loop of postmaster
|
|
*/
|
|
static int
|
|
ServerLoop(void)
|
|
{
|
|
fd_set readmask;
|
|
int nSockets;
|
|
time_t now,
|
|
last_touch_time;
|
|
struct timeval earlier,
|
|
later;
|
|
struct timezone tz;
|
|
|
|
gettimeofday(&earlier, &tz);
|
|
last_touch_time = time(NULL);
|
|
|
|
nSockets = initMasks(&readmask);
|
|
|
|
for (;;)
|
|
{
|
|
Port *port;
|
|
fd_set rmask;
|
|
struct timeval timeout;
|
|
int selres;
|
|
int i;
|
|
|
|
/*
|
|
* Wait for something to happen.
|
|
*
|
|
* We wait at most one minute, to ensure that the other background
|
|
* tasks handled below get done even when no requests are arriving.
|
|
*/
|
|
memcpy((char *) &rmask, (char *) &readmask, sizeof(fd_set));
|
|
|
|
timeout.tv_sec = 60;
|
|
timeout.tv_usec = 0;
|
|
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
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);
|
|
|
|
if (selres < 0)
|
|
{
|
|
if (errno == EINTR || errno == EWOULDBLOCK)
|
|
continue;
|
|
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)
|
|
{
|
|
/*
|
|
* Select a random seed at the time of first receiving a request.
|
|
*/
|
|
while (random_seed == 0)
|
|
{
|
|
gettimeofday(&later, &tz);
|
|
|
|
/*
|
|
* We are not sure how much precision is in tv_usec, so we
|
|
* swap the nibbles of 'later' and XOR them with 'earlier'. On
|
|
* the off chance that the result is 0, we loop until it isn't.
|
|
*/
|
|
random_seed = earlier.tv_usec ^
|
|
((later.tv_usec << 16) |
|
|
((later.tv_usec >> 16) & 0xffff));
|
|
}
|
|
|
|
for (i = 0; i < MAXLISTEN; i++)
|
|
{
|
|
if (ListenSocket[i] == -1)
|
|
break;
|
|
if (FD_ISSET(ListenSocket[i], &rmask))
|
|
{
|
|
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 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 && StartupPID == 0 && !FatalError)
|
|
{
|
|
BgWriterPID = StartBackgroundWriter();
|
|
/* If shutdown is pending, set it going */
|
|
if (Shutdown > NoShutdown && BgWriterPID != 0)
|
|
kill(BgWriterPID, SIGUSR2);
|
|
}
|
|
|
|
/* If we have lost the stats collector, try to start a new one */
|
|
if (PgStatPID == 0 &&
|
|
StartupPID == 0 && !FatalError && Shutdown == NoShutdown)
|
|
PgStatPID = pgstat_start();
|
|
|
|
/*
|
|
* Touch the socket and lock file at least every ten minutes, to ensure
|
|
* that they are not removed by overzealous /tmp-cleaning tasks.
|
|
*/
|
|
now = time(NULL);
|
|
if (now - last_touch_time >= 10 * 60)
|
|
{
|
|
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 nsocks = -1;
|
|
int i;
|
|
|
|
FD_ZERO(rmask);
|
|
|
|
for (i = 0; i < MAXLISTEN; i++)
|
|
{
|
|
int fd = ListenSocket[i];
|
|
|
|
if (fd == -1)
|
|
break;
|
|
FD_SET(fd, rmask);
|
|
if (fd > nsocks)
|
|
nsocks = fd;
|
|
}
|
|
|
|
return nsocks + 1;
|
|
}
|
|
|
|
|
|
/*
|
|
* Read the 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);
|
|
return 127; /* XXX */
|
|
}
|
|
|
|
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
|
|
if (send(port->sock, &SSLok, 1, 0) != 1)
|
|
{
|
|
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 won't disappear
|
|
* when we pass them to PostgresMain (see BackendRun). 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
|
|
{
|
|
/* 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';
|
|
|
|
/*
|
|
* 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_OK:
|
|
default:
|
|
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 = 0; i < NUM_BACKENDARRAY_ELEMS; 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)));
|
|
kill(bp->pid, SIGINT);
|
|
}
|
|
else
|
|
/* Right PID, wrong key: no way, Jose */
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("bad key in cancel request for process %d",
|
|
backendPID)));
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* No matching backend */
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("bad pid in cancel request for process %d",
|
|
backendPID)));
|
|
}
|
|
|
|
/*
|
|
* canAcceptConnections --- check to see if database state allows connections.
|
|
*/
|
|
static enum CAC_state
|
|
canAcceptConnections(void)
|
|
{
|
|
/* Can't start backends when in startup/shutdown/recovery state. */
|
|
if (Shutdown > NoShutdown)
|
|
return CAC_SHUTDOWN;
|
|
if (StartupPID)
|
|
return CAC_STARTUP;
|
|
if (FatalError)
|
|
return CAC_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.
|
|
*/
|
|
if (CountChildren() >= 2 * MaxBackends)
|
|
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)
|
|
{
|
|
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->cryptSalt, port->md5Salt);
|
|
}
|
|
|
|
return port;
|
|
}
|
|
|
|
|
|
/*
|
|
* ConnFree -- free a local connection data structure
|
|
*/
|
|
static void
|
|
ConnFree(Port *conn)
|
|
{
|
|
#ifdef USE_SSL
|
|
secure_close(conn);
|
|
#endif
|
|
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.
|
|
*/
|
|
void
|
|
ClosePostmasterPorts(void)
|
|
{
|
|
int i;
|
|
|
|
/* Close the listen sockets */
|
|
for (i = 0; i < MAXLISTEN; i++)
|
|
{
|
|
if (ListenSocket[i] != -1)
|
|
{
|
|
StreamClose(ListenSocket[i]);
|
|
ListenSocket[i] = -1;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* reset_shared -- reset shared memory and semaphores
|
|
*/
|
|
static void
|
|
reset_shared(unsigned short 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, MaxBackends, 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 (BgWriterPID != 0)
|
|
kill(BgWriterPID, SIGHUP);
|
|
/* PgStatPID does not currently need SIGHUP */
|
|
load_hba();
|
|
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 (DLGetHead(BackendList))
|
|
break; /* let reaper() handle this */
|
|
|
|
/*
|
|
* No children left. Begin shutdown of data base system.
|
|
*/
|
|
if (StartupPID != 0 || FatalError)
|
|
break; /* let reaper() handle this */
|
|
/* Start the bgwriter if not running */
|
|
if (BgWriterPID == 0)
|
|
BgWriterPID = StartBackgroundWriter();
|
|
/* And tell it to shut down */
|
|
if (BgWriterPID != 0)
|
|
kill(BgWriterPID, SIGUSR2);
|
|
/* Tell pgstat to shut down too; nothing left for it to do */
|
|
if (PgStatPID != 0)
|
|
kill(PgStatPID, SIGQUIT);
|
|
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 (DLGetHead(BackendList))
|
|
{
|
|
if (!FatalError)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("aborting any active transactions")));
|
|
SignalChildren(SIGTERM);
|
|
/* reaper() does the rest */
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* No children left. Begin shutdown of data base system.
|
|
*
|
|
* Note: if we previously got SIGTERM then we may send SIGUSR2
|
|
* to the bgwriter a second time here. This should be harmless.
|
|
*/
|
|
if (StartupPID != 0 || FatalError)
|
|
break; /* let reaper() handle this */
|
|
/* Start the bgwriter if not running */
|
|
if (BgWriterPID == 0)
|
|
BgWriterPID = StartBackgroundWriter();
|
|
/* And tell it to shut down */
|
|
if (BgWriterPID != 0)
|
|
kill(BgWriterPID, SIGUSR2);
|
|
/* Tell pgstat to shut down too; nothing left for it to do */
|
|
if (PgStatPID != 0)
|
|
kill(PgStatPID, SIGQUIT);
|
|
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")));
|
|
if (StartupPID != 0)
|
|
kill(StartupPID, SIGQUIT);
|
|
if (BgWriterPID != 0)
|
|
kill(BgWriterPID, SIGQUIT);
|
|
if (PgStatPID != 0)
|
|
kill(PgStatPID, SIGQUIT);
|
|
if (DLGetHead(BackendList))
|
|
SignalChildren(SIGQUIT);
|
|
ExitPostmaster(0);
|
|
break;
|
|
}
|
|
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
/*
|
|
* Reaper -- signal handler to cleanup after a backend (child) dies.
|
|
*/
|
|
static void
|
|
reaper(SIGNAL_ARGS)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
#ifdef HAVE_WAITPID
|
|
int status; /* backend exit status */
|
|
|
|
#else
|
|
#ifndef WIN32
|
|
union wait status; /* backend exit status */
|
|
#endif
|
|
#endif
|
|
int exitstatus;
|
|
int pid; /* process id of dead backend */
|
|
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
ereport(DEBUG4,
|
|
(errmsg_internal("reaping dead processes")));
|
|
#ifdef HAVE_WAITPID
|
|
while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
|
|
{
|
|
exitstatus = status;
|
|
#else
|
|
#ifndef WIN32
|
|
while ((pid = wait3(&status, WNOHANG, NULL)) > 0)
|
|
{
|
|
exitstatus = status.w_status;
|
|
#else
|
|
while ((pid = win32_waitpid(&exitstatus)) > 0)
|
|
{
|
|
/*
|
|
* We need to do this here, and not in CleanupProc, since this is
|
|
* to be called on all children when we are done with them. Could
|
|
* move to LogChildExit, but that seems like asking for future
|
|
* trouble...
|
|
*/
|
|
win32_RemoveChild(pid);
|
|
#endif /* WIN32 */
|
|
#endif /* HAVE_WAITPID */
|
|
|
|
/*
|
|
* Check if this child was a startup process.
|
|
*/
|
|
if (StartupPID != 0 && pid == StartupPID)
|
|
{
|
|
StartupPID = 0;
|
|
if (exitstatus != 0)
|
|
{
|
|
LogChildExit(LOG, gettext("startup process"),
|
|
pid, exitstatus);
|
|
ereport(LOG,
|
|
(errmsg("aborting startup due to startup process failure")));
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
/*
|
|
* Startup succeeded - we are done with system startup or recovery.
|
|
*/
|
|
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();
|
|
|
|
/*
|
|
* Go to shutdown mode if a shutdown request was pending.
|
|
* Otherwise, try to start the stats collector too.
|
|
*/
|
|
if (Shutdown > NoShutdown && BgWriterPID != 0)
|
|
kill(BgWriterPID, SIGUSR2);
|
|
else if (PgStatPID == 0 && Shutdown == NoShutdown)
|
|
PgStatPID = pgstat_start();
|
|
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Was it the bgwriter?
|
|
*/
|
|
if (BgWriterPID != 0 && pid == BgWriterPID)
|
|
{
|
|
BgWriterPID = 0;
|
|
if (exitstatus == 0 && Shutdown > NoShutdown &&
|
|
!FatalError && !DLGetHead(BackendList))
|
|
{
|
|
/*
|
|
* Normal postmaster exit is here: we've seen 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.)
|
|
*/
|
|
ExitPostmaster(0);
|
|
}
|
|
/*
|
|
* Any unexpected exit of the bgwriter is treated as a crash.
|
|
*/
|
|
LogChildExit(LOG, gettext("background writer process"),
|
|
pid, exitstatus);
|
|
HandleChildCrash(pid, exitstatus);
|
|
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 (PgStatPID != 0 && pid == PgStatPID)
|
|
{
|
|
PgStatPID = 0;
|
|
if (exitstatus != 0)
|
|
LogChildExit(LOG, gettext("statistics collector process"),
|
|
pid, exitstatus);
|
|
if (StartupPID == 0 && !FatalError && Shutdown == NoShutdown)
|
|
PgStatPID = pgstat_start();
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Else do standard backend child cleanup.
|
|
*/
|
|
CleanupProc(pid, exitstatus);
|
|
} /* loop over pending child-death reports */
|
|
|
|
if (FatalError)
|
|
{
|
|
/*
|
|
* Wait for all children exit, then reset shmem and
|
|
* StartupDataBase.
|
|
*/
|
|
if (DLGetHead(BackendList) || StartupPID != 0 || BgWriterPID != 0)
|
|
goto reaper_done;
|
|
ereport(LOG,
|
|
(errmsg("all server processes terminated; reinitializing")));
|
|
|
|
shmem_exit(0);
|
|
reset_shared(PostPortNumber);
|
|
|
|
StartupPID = StartupDataBase();
|
|
|
|
goto reaper_done;
|
|
}
|
|
|
|
if (Shutdown > NoShutdown)
|
|
{
|
|
if (DLGetHead(BackendList) || StartupPID != 0)
|
|
goto reaper_done;
|
|
/* Start the bgwriter if not running */
|
|
if (BgWriterPID == 0)
|
|
BgWriterPID = StartBackgroundWriter();
|
|
/* And tell it to shut down */
|
|
if (BgWriterPID != 0)
|
|
kill(BgWriterPID, SIGUSR2);
|
|
}
|
|
|
|
reaper_done:
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
|
|
/*
|
|
* CleanupProc -- cleanup after terminated backend.
|
|
*
|
|
* Remove all local state associated with backend.
|
|
*/
|
|
static void
|
|
CleanupProc(int pid,
|
|
int exitstatus) /* child's exit status. */
|
|
{
|
|
Dlelem *curr;
|
|
|
|
LogChildExit(DEBUG2, gettext("server process"), pid, exitstatus);
|
|
|
|
/*
|
|
* If a backend dies in an ugly way (i.e. exit status not 0) then we
|
|
* must signal all other backends to quickdie. If exit status is zero
|
|
* we assume everything is hunky dory and simply remove the backend
|
|
* from the active backend list.
|
|
*/
|
|
if (exitstatus != 0)
|
|
{
|
|
HandleChildCrash(pid, exitstatus);
|
|
return;
|
|
}
|
|
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
Backend *bp = (Backend *) DLE_VAL(curr);
|
|
|
|
if (bp->pid == pid)
|
|
{
|
|
DLRemove(curr);
|
|
free(bp);
|
|
DLFreeElem(curr);
|
|
#ifdef EXEC_BACKEND
|
|
ShmemBackendArrayRemove(pid);
|
|
#endif
|
|
/* Tell the collector about backend termination */
|
|
pgstat_beterm(pid);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* HandleChildCrash -- cleanup after failed backend or bgwriter.
|
|
*
|
|
* 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) /* child's exit status. */
|
|
{
|
|
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,
|
|
(pid == BgWriterPID) ?
|
|
gettext("background writer process") :
|
|
gettext("server process"),
|
|
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.
|
|
*/
|
|
DLRemove(curr);
|
|
free(bp);
|
|
DLFreeElem(curr);
|
|
#ifdef EXEC_BACKEND
|
|
ShmemBackendArrayRemove(pid);
|
|
#endif
|
|
/* Tell the collector about backend termination */
|
|
pgstat_beterm(pid);
|
|
/* 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.
|
|
*/
|
|
if (!FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
(SendStop ? "SIGSTOP" : "SIGQUIT"),
|
|
(int) bp->pid)));
|
|
kill(bp->pid, (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)));
|
|
kill(BgWriterPID, (SendStop ? SIGSTOP : SIGQUIT));
|
|
}
|
|
|
|
/* Force a power-cycle of the pgstat processes too */
|
|
/* (Shouldn't be necessary, but just for luck) */
|
|
if (PgStatPID != 0 && !FatalError)
|
|
{
|
|
ereport(DEBUG2,
|
|
(errmsg_internal("sending %s to process %d",
|
|
"SIGQUIT",
|
|
(int) PgStatPID)));
|
|
kill(PgStatPID, SIGQUIT);
|
|
}
|
|
|
|
FatalError = true;
|
|
}
|
|
|
|
/*
|
|
* 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))
|
|
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))));
|
|
else
|
|
ereport(lev,
|
|
|
|
/*
|
|
* translator: %s is a noun phrase describing a child process,
|
|
* such as "server process"
|
|
*/
|
|
(errmsg("%s (PID %d) exited with unexpected status %d",
|
|
procname, pid, exitstatus)));
|
|
}
|
|
|
|
/*
|
|
* Send a signal to all backend children (but NOT special children)
|
|
*/
|
|
static void
|
|
SignalChildren(int signal)
|
|
{
|
|
Dlelem *curr;
|
|
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
Backend *bp = (Backend *) DLE_VAL(curr);
|
|
|
|
ereport(DEBUG4,
|
|
(errmsg_internal("sending signal %d to process %d",
|
|
signal, (int) bp->pid)));
|
|
kill(bp->pid, signal);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* BackendStartup -- start backend process
|
|
*
|
|
* returns: STATUS_ERROR if the fork failed, STATUS_OK otherwise.
|
|
*/
|
|
static int
|
|
BackendStartup(Port *port)
|
|
{
|
|
Backend *bn; /* for backend cleanup */
|
|
pid_t pid;
|
|
|
|
#ifdef LINUX_PROFILE
|
|
struct itimerval prof_itimer;
|
|
#endif
|
|
|
|
/*
|
|
* 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();
|
|
|
|
/*
|
|
* Make room for 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;
|
|
}
|
|
|
|
/* Pass down canAcceptConnections state (kluge for EXEC_BACKEND case) */
|
|
port->canAcceptConnections = canAcceptConnections();
|
|
|
|
/*
|
|
* Flush stdio channels just before fork, to avoid double-output
|
|
* problems. Ideally we'd use fflush(NULL) here, but there are still a
|
|
* few non-ANSI stdio libraries out there (like SunOS 4.1.x) that
|
|
* coredump if we do. Presently stdout and stderr are the only stdio
|
|
* output channels used by the postmaster, so fflush'ing them should
|
|
* be sufficient.
|
|
*/
|
|
fflush(stdout);
|
|
fflush(stderr);
|
|
|
|
#ifdef EXEC_BACKEND
|
|
|
|
pid = backend_forkexec(port);
|
|
|
|
#else /* !EXEC_BACKEND */
|
|
|
|
#ifdef LINUX_PROFILE
|
|
|
|
/*
|
|
* Linux's fork() resets the profiling timer in the child process. If
|
|
* we want to profile child processes then we need to save and restore
|
|
* the timer setting. This is a waste of time if not profiling,
|
|
* however, so only do it if commanded by specific -DLINUX_PROFILE
|
|
* switch.
|
|
*/
|
|
getitimer(ITIMER_PROF, &prof_itimer);
|
|
#endif
|
|
|
|
#ifdef __BEOS__
|
|
/* Specific beos actions before backend startup */
|
|
beos_before_backend_startup();
|
|
#endif
|
|
|
|
pid = fork();
|
|
|
|
if (pid == 0) /* child */
|
|
{
|
|
#ifdef LINUX_PROFILE
|
|
setitimer(ITIMER_PROF, &prof_itimer, NULL);
|
|
#endif
|
|
|
|
#ifdef __BEOS__
|
|
/* Specific beos backend startup actions */
|
|
beos_backend_startup();
|
|
#endif
|
|
free(bn);
|
|
|
|
proc_exit(BackendRun(port));
|
|
}
|
|
|
|
#endif /* EXEC_BACKEND */
|
|
|
|
if (pid < 0)
|
|
{
|
|
/* in parent, fork failed */
|
|
int save_errno = errno;
|
|
|
|
#ifdef __BEOS__
|
|
/* Specific beos backend startup actions */
|
|
beos_backend_startup_failed();
|
|
#endif
|
|
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->cancel_key = MyCancelKey;
|
|
DLAddHead(BackendList, DLNewElem(bn));
|
|
#ifdef EXEC_BACKEND
|
|
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];
|
|
|
|
/* Format the error message packet (always V2 protocol) */
|
|
snprintf(buffer, sizeof(buffer), "E%s%s\n",
|
|
gettext("could not fork new process for connection: "),
|
|
strerror(errnum));
|
|
|
|
/* Set port to non-blocking. Don't do send() if this fails */
|
|
if (!set_noblock(port->sock))
|
|
return;
|
|
|
|
send(port->sock, buffer, strlen(buffer) + 1, 0);
|
|
}
|
|
|
|
|
|
/*
|
|
* split_opts -- split a string of options and append it to an argv array
|
|
*
|
|
* NB: the string is destructively modified!
|
|
*
|
|
* Since no current POSTGRES arguments require any quoting characters,
|
|
* we can use the simple-minded tactic of assuming each set of space-
|
|
* delimited characters is a separate argv element.
|
|
*
|
|
* If you don't like that, well, we *used* to pass the whole option string
|
|
* as ONE argument to execl(), which was even less intelligent...
|
|
*/
|
|
static void
|
|
split_opts(char **argv, int *argcp, char *s)
|
|
{
|
|
while (s && *s)
|
|
{
|
|
while (isspace((unsigned char) *s))
|
|
++s;
|
|
if (*s == '\0')
|
|
break;
|
|
argv[(*argcp)++] = s;
|
|
while (*s && !isspace((unsigned char) *s))
|
|
++s;
|
|
if (*s)
|
|
*s++ = '\0';
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* BackendRun -- perform authentication, and if successful,
|
|
* 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)
|
|
{
|
|
int status;
|
|
struct timeval now;
|
|
struct timezone tz;
|
|
char remote_host[NI_MAXHOST];
|
|
char remote_port[NI_MAXSERV];
|
|
char remote_ps_data[NI_MAXHOST];
|
|
char **av;
|
|
int maxac;
|
|
int ac;
|
|
char debugbuf[32];
|
|
char protobuf[32];
|
|
int i;
|
|
|
|
IsUnderPostmaster = true; /* we are a postmaster subprocess now */
|
|
|
|
/*
|
|
* Let's clean up ourselves as the postmaster child, and close the
|
|
* postmaster's listen sockets
|
|
*/
|
|
ClosePostmasterPorts();
|
|
|
|
/* We don't want the postmaster's proc_exit() handlers */
|
|
on_exit_reset();
|
|
|
|
/*
|
|
* Signal handlers setting is moved to tcop/postgres...
|
|
*/
|
|
|
|
/* Save port etc. for ps status */
|
|
MyProcPort = port;
|
|
|
|
/* Reset MyProcPid to new backend's pid */
|
|
MyProcPid = getpid();
|
|
|
|
/*
|
|
* 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 the -W backend switch, which we allow clients to pass through
|
|
* PGOPTIONS, but it is not honored until after authentication.)
|
|
*/
|
|
if (PreAuthDelay > 0)
|
|
pg_usleep(PreAuthDelay * 1000000L);
|
|
|
|
ClientAuthInProgress = true; /* limit visibility of log messages */
|
|
|
|
/* save start time for end of session reporting */
|
|
gettimeofday(&(port->session_start), NULL);
|
|
|
|
/* set these to empty in case they are needed before we set them up */
|
|
port->remote_host = "";
|
|
port->remote_port = "";
|
|
port->commandTag = "";
|
|
|
|
/*
|
|
* 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 = Remote; /* now safe to ereport to client */
|
|
|
|
/*
|
|
* We arrange for a simple exit(0) if we receive SIGTERM or SIGQUIT
|
|
* during any client authentication related communication. Otherwise
|
|
* the postmaster cannot shutdown the database FAST or IMMED cleanly
|
|
* if a buggy client blocks a backend during authentication.
|
|
*/
|
|
pqsignal(SIGTERM, authdie);
|
|
pqsignal(SIGQUIT, authdie);
|
|
pqsignal(SIGALRM, authdie);
|
|
PG_SETMASK(&AuthBlockSig);
|
|
|
|
/*
|
|
* Get the remote host name and port for logging and status display.
|
|
*/
|
|
remote_host[0] = '\0';
|
|
remote_port[0] = '\0';
|
|
if (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 = 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("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)
|
|
ereport(LOG,
|
|
(errmsg("connection received: host=%s port=%s",
|
|
remote_host, remote_port)));
|
|
|
|
/*
|
|
* save remote_host and remote_port in port stucture
|
|
*/
|
|
port->remote_host = strdup(remote_host);
|
|
port->remote_port = strdup(remote_port);
|
|
|
|
/*
|
|
* In EXEC_BACKEND case, we didn't inherit the contents of pg_hba.c
|
|
* etcetera from the postmaster, and have to load them ourselves.
|
|
* Build the PostmasterContext (which didn't exist before, in this
|
|
* process) to contain the data.
|
|
*
|
|
* FIXME: [fork/exec] Ugh. Is there a way around this overhead?
|
|
*/
|
|
#ifdef EXEC_BACKEND
|
|
Assert(PostmasterContext == NULL);
|
|
PostmasterContext = AllocSetContextCreate(TopMemoryContext,
|
|
"Postmaster",
|
|
ALLOCSET_DEFAULT_MINSIZE,
|
|
ALLOCSET_DEFAULT_INITSIZE,
|
|
ALLOCSET_DEFAULT_MAXSIZE);
|
|
MemoryContextSwitchTo(PostmasterContext);
|
|
|
|
load_hba();
|
|
load_ident();
|
|
load_user();
|
|
load_group();
|
|
#endif
|
|
|
|
/*
|
|
* Ready to begin client interaction. We will give up and exit(0)
|
|
* after a time delay, so that a broken client can't hog a connection
|
|
* indefinitely. PreAuthDelay doesn't count against the time limit.
|
|
*/
|
|
if (!enable_sig_alarm(AuthenticationTimeout * 1000, false))
|
|
elog(FATAL, "could not set timer for authorization timeout");
|
|
|
|
/*
|
|
* Receive the startup packet (which might turn out to be a cancel
|
|
* request packet).
|
|
*/
|
|
status = ProcessStartupPacket(port, false);
|
|
|
|
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.
|
|
*/
|
|
init_ps_display(port->user_name, port->database_name, remote_ps_data);
|
|
set_ps_display("authentication");
|
|
|
|
/*
|
|
* Now perform authentication exchange.
|
|
*/
|
|
ClientAuthentication(port); /* might not return, if failure */
|
|
|
|
/*
|
|
* Done with authentication. Disable timeout, and prevent
|
|
* SIGTERM/SIGQUIT again until backend startup is complete.
|
|
*/
|
|
if (!disable_sig_alarm(false))
|
|
elog(FATAL, "could not disable timer for authorization timeout");
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
if (Log_connections)
|
|
ereport(LOG,
|
|
(errmsg("connection authorized: user=%s database=%s",
|
|
port->user_name, port->database_name)));
|
|
|
|
/*
|
|
* 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;
|
|
gettimeofday(&now, &tz);
|
|
srandom((unsigned int) now.tv_usec);
|
|
|
|
|
|
/* ----------------
|
|
* Now, build the argv vector that will be given to PostgresMain.
|
|
*
|
|
* The layout of the command line is
|
|
* postgres [secure switches] -p databasename [insecure switches]
|
|
* where the switches after -p come from the client request.
|
|
*
|
|
* The maximum possible number of commandline arguments that could come
|
|
* from ExtraOptions or port->cmdline_options is (strlen + 1) / 2; see
|
|
* split_opts().
|
|
* ----------------
|
|
*/
|
|
maxac = 10; /* for fixed args supplied below */
|
|
maxac += (strlen(ExtraOptions) + 1) / 2;
|
|
if (port->cmdline_options)
|
|
maxac += (strlen(port->cmdline_options) + 1) / 2;
|
|
|
|
av = (char **) MemoryContextAlloc(TopMemoryContext,
|
|
maxac * sizeof(char *));
|
|
ac = 0;
|
|
|
|
av[ac++] = "postgres";
|
|
|
|
/*
|
|
* Pass the requested debugging level along to the backend.
|
|
*/
|
|
if (debug_flag > 0)
|
|
{
|
|
snprintf(debugbuf, sizeof(debugbuf), "-d%d", debug_flag);
|
|
av[ac++] = debugbuf;
|
|
}
|
|
|
|
/*
|
|
* Pass any backend switches specified with -o in 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.)
|
|
*/
|
|
split_opts(av, &ac, ExtraOptions);
|
|
|
|
/* Tell the backend what protocol the frontend is using. */
|
|
snprintf(protobuf, sizeof(protobuf), "-v%u", port->proto);
|
|
av[ac++] = protobuf;
|
|
|
|
/*
|
|
* Tell the backend it is being called from the postmaster, and which
|
|
* database to use. -p marks the end of secure switches.
|
|
*/
|
|
av[ac++] = "-p";
|
|
av[ac++] = port->database_name;
|
|
|
|
/*
|
|
* Pass the (insecure) option switches from the connection request.
|
|
* (It's OK to mangle port->cmdline_options now.)
|
|
*/
|
|
if (port->cmdline_options)
|
|
split_opts(av, &ac, port->cmdline_options);
|
|
|
|
av[ac] = NULL;
|
|
|
|
Assert(ac < maxac);
|
|
|
|
/*
|
|
* Release postmaster's working memory context so that backend can
|
|
* recycle the space. Note this does not trash *MyProcPort, because
|
|
* ConnCreate() allocated that space with malloc() ... else we'd need
|
|
* to copy the Port data here. Also, subsidiary data such as the
|
|
* username isn't lost either; see ProcessStartupPacket().
|
|
*/
|
|
MemoryContextSwitchTo(TopMemoryContext);
|
|
MemoryContextDelete(PostmasterContext);
|
|
PostmasterContext = NULL;
|
|
|
|
/*
|
|
* Debug: print arguments being passed to backend
|
|
*/
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("%s child[%d]: starting with (",
|
|
progname, getpid())));
|
|
for (i = 0; i < ac; ++i)
|
|
ereport(DEBUG3,
|
|
(errmsg_internal("\t%s", av[i])));
|
|
ereport(DEBUG3,
|
|
(errmsg_internal(")")));
|
|
|
|
ClientAuthInProgress = false; /* client_min_messages is active
|
|
* now */
|
|
|
|
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
|
|
*
|
|
* 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);
|
|
}
|
|
|
|
static pid_t
|
|
internal_forkexec(int argc, char *argv[], Port *port)
|
|
{
|
|
pid_t pid;
|
|
char tmpfilename[MAXPGPATH];
|
|
|
|
if (!write_backend_variables(tmpfilename, port))
|
|
return -1; /* log made by write_backend_variables */
|
|
|
|
/* Make sure caller set up argv properly */
|
|
Assert(argc >= 3);
|
|
Assert(argv[argc] == NULL);
|
|
Assert(strncmp(argv[1], "-fork", 5) == 0);
|
|
Assert(argv[2] == NULL);
|
|
|
|
/* Insert temp file name after -fork argument */
|
|
argv[2] = tmpfilename;
|
|
|
|
#ifdef WIN32
|
|
pid = win32_forkexec(postgres_exec_path, argv);
|
|
#else
|
|
/* Fire off execv in child */
|
|
if ((pid = fork()) == 0)
|
|
{
|
|
if (execv(postgres_exec_path, argv) < 0)
|
|
{
|
|
ereport(LOG,
|
|
(errmsg("could not exec backend process \"%s\": %m",
|
|
postgres_exec_path)));
|
|
/* We're already in the child process here, can't return */
|
|
exit(1);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
return pid; /* Parent returns pid, or -1 on fork failure */
|
|
}
|
|
|
|
/*
|
|
* 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 */
|
|
|
|
/* In EXEC_BACKEND case we will not have inherited these settings */
|
|
IsPostmasterEnvironment = true;
|
|
whereToSendOutput = None;
|
|
pqinitmask();
|
|
PG_SETMASK(&BlockSig);
|
|
|
|
/* Setup essential subsystems */
|
|
MemoryContextInit();
|
|
InitializeGUCOptions();
|
|
|
|
/* Check we got appropriate args */
|
|
if (argc < 3)
|
|
elog(FATAL, "invalid subpostmaster invocation");
|
|
|
|
/* Read in file-based context */
|
|
memset(&port, 0, sizeof(Port));
|
|
read_backend_variables(argv[2], &port);
|
|
read_nondefault_variables();
|
|
|
|
/* Run backend or appropriate child */
|
|
if (strcmp(argv[1], "-forkbackend") == 0)
|
|
{
|
|
/* BackendRun will close sockets */
|
|
|
|
/* Attach process to shared segments */
|
|
CreateSharedMemoryAndSemaphores(false, MaxBackends, 0);
|
|
|
|
Assert(argc == 3); /* shouldn't be any more args */
|
|
proc_exit(BackendRun(&port));
|
|
}
|
|
if (strcmp(argv[1], "-forkboot") == 0)
|
|
{
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts();
|
|
|
|
/* Attach process to shared segments */
|
|
CreateSharedMemoryAndSemaphores(false, MaxBackends, 0);
|
|
|
|
BootstrapMain(argc - 2, argv + 2);
|
|
proc_exit(0);
|
|
}
|
|
if (strcmp(argv[1], "-forkbuf") == 0)
|
|
{
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts();
|
|
|
|
/* Do not want to attach to shared memory */
|
|
|
|
PgstatBufferMain(argc, argv);
|
|
proc_exit(0);
|
|
}
|
|
if (strcmp(argv[1], "-forkcol") == 0)
|
|
{
|
|
/*
|
|
* Do NOT close postmaster sockets here, because we are forking from
|
|
* pgstat buffer process, which already did it.
|
|
*/
|
|
|
|
/* Do not want to attach to shared memory */
|
|
|
|
PgstatCollectorMain(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);
|
|
|
|
if (CheckPostmasterSignal(PMSIGNAL_PASSWORD_CHANGE))
|
|
{
|
|
/*
|
|
* Password or group file has changed.
|
|
*/
|
|
load_user();
|
|
load_group();
|
|
}
|
|
|
|
if (CheckPostmasterSignal(PMSIGNAL_WAKEN_CHILDREN))
|
|
{
|
|
/*
|
|
* Send SIGUSR1 to all children (triggers
|
|
* CatchupInterruptHandler). See storage/ipc/sinval[adt].c for the
|
|
* use of this.
|
|
*/
|
|
if (Shutdown <= SmartShutdown)
|
|
SignalChildren(SIGUSR1);
|
|
}
|
|
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
}
|
|
|
|
|
|
/*
|
|
* CharRemap: given an int in range 0..61, produce textual encoding of it
|
|
* per crypt(3) conventions.
|
|
*/
|
|
static char
|
|
CharRemap(long ch)
|
|
{
|
|
if (ch < 0)
|
|
ch = -ch;
|
|
ch = ch % 62;
|
|
|
|
if (ch < 26)
|
|
return 'A' + ch;
|
|
|
|
ch -= 26;
|
|
if (ch < 26)
|
|
return 'a' + ch;
|
|
|
|
ch -= 26;
|
|
return '0' + ch;
|
|
}
|
|
|
|
/*
|
|
* RandomSalt
|
|
*/
|
|
static void
|
|
RandomSalt(char *cryptSalt, char *md5Salt)
|
|
{
|
|
long rand = PostmasterRandom();
|
|
|
|
cryptSalt[0] = CharRemap(rand % 62);
|
|
cryptSalt[1] = CharRemap(rand / 62);
|
|
|
|
/*
|
|
* It's okay to reuse the first random value for one of the MD5 salt
|
|
* bytes, since only one of the two salts will be sent to the client.
|
|
* After that we need to compute more random bits.
|
|
*
|
|
* 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.
|
|
*/
|
|
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)
|
|
{
|
|
static bool initialized = false;
|
|
|
|
if (!initialized)
|
|
{
|
|
Assert(random_seed != 0);
|
|
srandom(random_seed);
|
|
initialized = true;
|
|
}
|
|
|
|
return random();
|
|
}
|
|
|
|
/*
|
|
* Count up number of child processes (regular backends only)
|
|
*/
|
|
static int
|
|
CountChildren(void)
|
|
{
|
|
Dlelem *curr;
|
|
int cnt = 0;
|
|
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
cnt++;
|
|
}
|
|
return cnt;
|
|
}
|
|
|
|
|
|
/*
|
|
* StartChildProcess -- start a non-backend child process for the postmaster
|
|
*
|
|
* xlog determines what kind of child will be started. All child types
|
|
* initially go to BootstrapMain, which will handle common setup.
|
|
*
|
|
* Return value of StartChildProcess is subprocess' PID, or 0 if failed
|
|
* to start subprocess.
|
|
*/
|
|
static pid_t
|
|
StartChildProcess(int xlop)
|
|
{
|
|
pid_t pid;
|
|
char *av[10];
|
|
int ac = 0;
|
|
char xlbuf[32];
|
|
#ifdef LINUX_PROFILE
|
|
struct itimerval prof_itimer;
|
|
#endif
|
|
|
|
/*
|
|
* 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(xlbuf, sizeof(xlbuf), "-x%d", xlop);
|
|
av[ac++] = xlbuf;
|
|
|
|
av[ac++] = "-p";
|
|
av[ac++] = "template1";
|
|
|
|
av[ac] = NULL;
|
|
Assert(ac < lengthof(av));
|
|
|
|
/*
|
|
* Flush stdio channels (see comments in BackendStartup)
|
|
*/
|
|
fflush(stdout);
|
|
fflush(stderr);
|
|
|
|
#ifdef EXEC_BACKEND
|
|
|
|
pid = postmaster_forkexec(ac, av);
|
|
|
|
#else /* !EXEC_BACKEND */
|
|
|
|
#ifdef LINUX_PROFILE
|
|
/* see comments in BackendStartup */
|
|
getitimer(ITIMER_PROF, &prof_itimer);
|
|
#endif
|
|
|
|
#ifdef __BEOS__
|
|
/* Specific beos actions before backend startup */
|
|
beos_before_backend_startup();
|
|
#endif
|
|
|
|
pid = fork();
|
|
|
|
if (pid == 0) /* child */
|
|
{
|
|
#ifdef LINUX_PROFILE
|
|
setitimer(ITIMER_PROF, &prof_itimer, NULL);
|
|
#endif
|
|
|
|
#ifdef __BEOS__
|
|
/* Specific beos actions after backend startup */
|
|
beos_backend_startup();
|
|
#endif
|
|
|
|
IsUnderPostmaster = true; /* we are a postmaster subprocess now */
|
|
|
|
/* Close the postmaster's sockets */
|
|
ClosePostmasterPorts();
|
|
|
|
/* Lose the postmaster's on-exit routines and port connections */
|
|
on_exit_reset();
|
|
|
|
BootstrapMain(ac, av);
|
|
ExitPostmaster(0);
|
|
}
|
|
|
|
#endif /* EXEC_BACKEND */
|
|
|
|
if (pid < 0)
|
|
{
|
|
/* in parent, fork failed */
|
|
int save_errno = errno;
|
|
|
|
#ifdef __BEOS__
|
|
/* Specific beos actions before backend startup */
|
|
beos_backend_startup_failed();
|
|
#endif
|
|
errno = save_errno;
|
|
switch (xlop)
|
|
{
|
|
case BS_XLOG_STARTUP:
|
|
ereport(LOG,
|
|
(errmsg("could not fork startup process: %m")));
|
|
break;
|
|
case BS_XLOG_BGWRITER:
|
|
ereport(LOG,
|
|
(errmsg("could not fork background writer 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 (xlop == BS_XLOG_STARTUP)
|
|
ExitPostmaster(1);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* in parent, successful fork
|
|
*/
|
|
return pid;
|
|
}
|
|
|
|
|
|
/*
|
|
* Create the opts file
|
|
*/
|
|
static bool
|
|
CreateOptsFile(int argc, char *argv[], char *fullprogname)
|
|
{
|
|
char filename[MAXPGPATH];
|
|
FILE *fp;
|
|
int i;
|
|
|
|
snprintf(filename, sizeof(filename), "%s/postmaster.opts", DataDir);
|
|
|
|
if ((fp = fopen(filename, "w")) == NULL)
|
|
{
|
|
elog(LOG, "could not create file \"%s\": %m", filename);
|
|
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", filename);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
#ifdef EXEC_BACKEND
|
|
|
|
/*
|
|
* The following need to be available to the read/write_backend_variables
|
|
* functions
|
|
*/
|
|
#include "storage/spin.h"
|
|
|
|
extern slock_t *ShmemLock;
|
|
extern slock_t *ShmemIndexLock;
|
|
extern void *ShmemIndexAlloc;
|
|
typedef struct LWLock LWLock;
|
|
extern LWLock *LWLockArray;
|
|
extern slock_t *ProcStructLock;
|
|
extern int pgStatSock;
|
|
|
|
#define write_var(var,fp) fwrite((void*)&(var),sizeof(var),1,fp)
|
|
#define read_var(var,fp) fread((void*)&(var),sizeof(var),1,fp)
|
|
#define write_array_var(var,fp) fwrite((void*)(var),sizeof(var),1,fp)
|
|
#define read_array_var(var,fp) fread((void*)(var),sizeof(var),1,fp)
|
|
|
|
static bool
|
|
write_backend_variables(char *filename, Port *port)
|
|
{
|
|
static unsigned long tmpBackendFileNum = 0;
|
|
FILE *fp;
|
|
char str_buf[MAXPGPATH];
|
|
|
|
/* Calculate name for temp file in caller's buffer */
|
|
Assert(DataDir);
|
|
snprintf(filename, MAXPGPATH, "%s/%s/%s.backend_var.%d.%lu",
|
|
DataDir, PG_TEMP_FILES_DIR, PG_TEMP_FILE_PREFIX,
|
|
MyProcPid, ++tmpBackendFileNum);
|
|
|
|
/* Open file */
|
|
fp = AllocateFile(filename, PG_BINARY_W);
|
|
if (!fp)
|
|
{
|
|
/* As per OpenTemporaryFile... */
|
|
char dirname[MAXPGPATH];
|
|
|
|
snprintf(dirname, MAXPGPATH, "%s/%s", DataDir, PG_TEMP_FILES_DIR);
|
|
mkdir(dirname, S_IRWXU);
|
|
|
|
fp = AllocateFile(filename, PG_BINARY_W);
|
|
if (!fp)
|
|
{
|
|
ereport(LOG,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not create file \"%s\": %m",
|
|
filename)));
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/* Write vars */
|
|
write_var(port->sock, fp);
|
|
write_var(port->proto, fp);
|
|
write_var(port->laddr, fp);
|
|
write_var(port->raddr, fp);
|
|
write_var(port->canAcceptConnections, fp);
|
|
write_var(port->cryptSalt, fp);
|
|
write_var(port->md5Salt, fp);
|
|
|
|
/*
|
|
* XXX FIXME later: writing these strings as MAXPGPATH bytes always is
|
|
* probably a waste of resources
|
|
*/
|
|
|
|
StrNCpy(str_buf, DataDir, MAXPGPATH);
|
|
write_array_var(str_buf, fp);
|
|
|
|
write_array_var(ListenSocket, fp);
|
|
|
|
write_var(MyCancelKey, fp);
|
|
|
|
write_var(UsedShmemSegID, fp);
|
|
write_var(UsedShmemSegAddr, fp);
|
|
|
|
write_var(ShmemLock, fp);
|
|
write_var(ShmemIndexLock, fp);
|
|
write_var(ShmemVariableCache, fp);
|
|
write_var(ShmemIndexAlloc, fp);
|
|
write_var(ShmemBackendArray, fp);
|
|
|
|
write_var(LWLockArray, fp);
|
|
write_var(ProcStructLock, fp);
|
|
write_var(pgStatSock, fp);
|
|
|
|
write_var(debug_flag, fp);
|
|
write_var(PostmasterPid, fp);
|
|
#ifdef WIN32
|
|
write_var(PostmasterHandle, fp);
|
|
#endif
|
|
|
|
StrNCpy(str_buf, my_exec_path, MAXPGPATH);
|
|
write_array_var(str_buf, fp);
|
|
|
|
write_array_var(ExtraOptions, fp);
|
|
|
|
StrNCpy(str_buf, setlocale(LC_COLLATE, NULL), MAXPGPATH);
|
|
write_array_var(str_buf, fp);
|
|
StrNCpy(str_buf, setlocale(LC_CTYPE, NULL), MAXPGPATH);
|
|
write_array_var(str_buf, fp);
|
|
|
|
/* Release file */
|
|
if (FreeFile(fp))
|
|
{
|
|
ereport(ERROR,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not write to file \"%s\": %m", filename)));
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
static void
|
|
read_backend_variables(char *filename, Port *port)
|
|
{
|
|
FILE *fp;
|
|
char str_buf[MAXPGPATH];
|
|
|
|
/* Open file */
|
|
fp = AllocateFile(filename, PG_BINARY_R);
|
|
if (!fp)
|
|
ereport(FATAL,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not read from backend variables file \"%s\": %m",
|
|
filename)));
|
|
|
|
/* Read vars */
|
|
read_var(port->sock, fp);
|
|
read_var(port->proto, fp);
|
|
read_var(port->laddr, fp);
|
|
read_var(port->raddr, fp);
|
|
read_var(port->canAcceptConnections, fp);
|
|
read_var(port->cryptSalt, fp);
|
|
read_var(port->md5Salt, fp);
|
|
|
|
read_array_var(str_buf, fp);
|
|
SetDataDir(str_buf);
|
|
|
|
read_array_var(ListenSocket, fp);
|
|
|
|
read_var(MyCancelKey, fp);
|
|
|
|
read_var(UsedShmemSegID, fp);
|
|
read_var(UsedShmemSegAddr, fp);
|
|
|
|
read_var(ShmemLock, fp);
|
|
read_var(ShmemIndexLock, fp);
|
|
read_var(ShmemVariableCache, fp);
|
|
read_var(ShmemIndexAlloc, fp);
|
|
read_var(ShmemBackendArray, fp);
|
|
|
|
read_var(LWLockArray, fp);
|
|
read_var(ProcStructLock, fp);
|
|
read_var(pgStatSock, fp);
|
|
|
|
read_var(debug_flag, fp);
|
|
read_var(PostmasterPid, fp);
|
|
#ifdef WIN32
|
|
read_var(PostmasterHandle, fp);
|
|
#endif
|
|
|
|
read_array_var(str_buf, fp);
|
|
StrNCpy(my_exec_path, str_buf, MAXPGPATH);
|
|
|
|
read_array_var(ExtraOptions, fp);
|
|
|
|
read_array_var(str_buf, fp);
|
|
setlocale(LC_COLLATE, str_buf);
|
|
read_array_var(str_buf, fp);
|
|
setlocale(LC_CTYPE, str_buf);
|
|
|
|
/* Release file */
|
|
FreeFile(fp);
|
|
if (unlink(filename) != 0)
|
|
ereport(WARNING,
|
|
(errcode_for_file_access(),
|
|
errmsg("could not remove file \"%s\": %m", filename)));
|
|
}
|
|
|
|
|
|
size_t
|
|
ShmemBackendArraySize(void)
|
|
{
|
|
return (NUM_BACKENDARRAY_ELEMS * sizeof(Backend));
|
|
}
|
|
|
|
void
|
|
ShmemBackendArrayAllocation(void)
|
|
{
|
|
size_t size = ShmemBackendArraySize();
|
|
|
|
ShmemBackendArray = (Backend *) ShmemAlloc(size);
|
|
/* Mark all slots as empty */
|
|
memset(ShmemBackendArray, 0, size);
|
|
}
|
|
|
|
static void
|
|
ShmemBackendArrayAdd(Backend *bn)
|
|
{
|
|
int i;
|
|
|
|
/* Find an empty slot */
|
|
for (i = 0; i < NUM_BACKENDARRAY_ELEMS; i++)
|
|
{
|
|
if (ShmemBackendArray[i].pid == 0)
|
|
{
|
|
ShmemBackendArray[i] = *bn;
|
|
return;
|
|
}
|
|
}
|
|
|
|
ereport(FATAL,
|
|
(errmsg_internal("no free slots in shmem backend array")));
|
|
}
|
|
|
|
static void
|
|
ShmemBackendArrayRemove(pid_t pid)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < NUM_BACKENDARRAY_ELEMS; i++)
|
|
{
|
|
if (ShmemBackendArray[i].pid == pid)
|
|
{
|
|
/* Mark the slot as empty */
|
|
ShmemBackendArray[i].pid = 0;
|
|
return;
|
|
}
|
|
}
|
|
|
|
ereport(WARNING,
|
|
(errmsg_internal("could not find backend entry with pid %d",
|
|
(int) pid)));
|
|
}
|
|
|
|
#endif /* EXEC_BACKEND */
|
|
|
|
|
|
#ifdef WIN32
|
|
|
|
static pid_t
|
|
win32_forkexec(const char *path, char *argv[])
|
|
{
|
|
STARTUPINFO si;
|
|
PROCESS_INFORMATION pi;
|
|
int i;
|
|
int j;
|
|
char cmdLine[MAXPGPATH * 2];
|
|
HANDLE childHandleCopy;
|
|
HANDLE waiterThread;
|
|
|
|
/* Format the cmd line */
|
|
cmdLine[sizeof(cmdLine)-1] = '\0';
|
|
cmdLine[sizeof(cmdLine)-2] = '\0';
|
|
snprintf(cmdLine, sizeof(cmdLine)-1, "\"%s\"", 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);
|
|
if (!CreateProcess(NULL, cmdLine, NULL, NULL, TRUE, 0, NULL, NULL, &si, &pi))
|
|
{
|
|
elog(LOG, "CreateProcess call failed (%d): %m", (int) GetLastError());
|
|
return -1;
|
|
}
|
|
|
|
if (!IsUnderPostmaster)
|
|
{
|
|
/* We are the Postmaster creating a child... */
|
|
win32_AddChild(pi.dwProcessId, pi.hProcess);
|
|
}
|
|
|
|
if (DuplicateHandle(GetCurrentProcess(),
|
|
pi.hProcess,
|
|
GetCurrentProcess(),
|
|
&childHandleCopy,
|
|
0,
|
|
FALSE,
|
|
DUPLICATE_SAME_ACCESS) == 0)
|
|
ereport(FATAL,
|
|
(errmsg_internal("could not duplicate child handle: %d",
|
|
(int) GetLastError())));
|
|
|
|
waiterThread = CreateThread(NULL, 64 * 1024, win32_sigchld_waiter,
|
|
(LPVOID) childHandleCopy, 0, NULL);
|
|
if (!waiterThread)
|
|
ereport(FATAL,
|
|
(errmsg_internal("could not create sigchld waiter thread: %d",
|
|
(int) GetLastError())));
|
|
CloseHandle(waiterThread);
|
|
|
|
if (IsUnderPostmaster)
|
|
CloseHandle(pi.hProcess);
|
|
CloseHandle(pi.hThread);
|
|
|
|
return pi.dwProcessId;
|
|
}
|
|
|
|
/*
|
|
* Note: The following three functions must not be interrupted (eg. by
|
|
* signals). As the Postgres Win32 signalling architecture (currently)
|
|
* requires polling, or APC checking functions which aren't used here, this
|
|
* is not an issue.
|
|
*
|
|
* We keep two separate arrays, instead of a single array of pid/HANDLE
|
|
* structs, to avoid having to re-create a handle array for
|
|
* WaitForMultipleObjects on each call to win32_waitpid.
|
|
*/
|
|
|
|
static void
|
|
win32_AddChild(pid_t pid, HANDLE handle)
|
|
{
|
|
Assert(win32_childPIDArray && win32_childHNDArray);
|
|
if (win32_numChildren < NUM_BACKENDARRAY_ELEMS)
|
|
{
|
|
win32_childPIDArray[win32_numChildren] = pid;
|
|
win32_childHNDArray[win32_numChildren] = handle;
|
|
++win32_numChildren;
|
|
}
|
|
else
|
|
ereport(FATAL,
|
|
(errmsg_internal("no room for child entry with pid %lu",
|
|
(unsigned long) pid)));
|
|
}
|
|
|
|
static void
|
|
win32_RemoveChild(pid_t pid)
|
|
{
|
|
int i;
|
|
|
|
Assert(win32_childPIDArray && win32_childHNDArray);
|
|
|
|
for (i = 0; i < win32_numChildren; i++)
|
|
{
|
|
if (win32_childPIDArray[i] == pid)
|
|
{
|
|
CloseHandle(win32_childHNDArray[i]);
|
|
|
|
/* Swap last entry into the "removed" one */
|
|
--win32_numChildren;
|
|
win32_childPIDArray[i] = win32_childPIDArray[win32_numChildren];
|
|
win32_childHNDArray[i] = win32_childHNDArray[win32_numChildren];
|
|
return;
|
|
}
|
|
}
|
|
|
|
ereport(WARNING,
|
|
(errmsg_internal("could not find child entry with pid %lu",
|
|
(unsigned long) pid)));
|
|
}
|
|
|
|
static pid_t
|
|
win32_waitpid(int *exitstatus)
|
|
{
|
|
Assert(win32_childPIDArray && win32_childHNDArray);
|
|
elog(DEBUG3, "waiting on %lu children", win32_numChildren);
|
|
|
|
if (win32_numChildren > 0)
|
|
{
|
|
/*
|
|
* Note: Do NOT use WaitForMultipleObjectsEx, as we don't want to
|
|
* run queued APCs here.
|
|
*/
|
|
int index;
|
|
DWORD exitCode;
|
|
DWORD ret;
|
|
|
|
ret = WaitForMultipleObjects(win32_numChildren, win32_childHNDArray,
|
|
FALSE, 0);
|
|
switch (ret)
|
|
{
|
|
case WAIT_FAILED:
|
|
ereport(LOG,
|
|
(errmsg_internal("failed to wait on %lu children: %d",
|
|
win32_numChildren, (int) GetLastError())));
|
|
return -1;
|
|
|
|
case WAIT_TIMEOUT:
|
|
/* No children have finished */
|
|
return -1;
|
|
|
|
default:
|
|
|
|
/*
|
|
* Get the exit code, and return the PID of, the
|
|
* respective process
|
|
*/
|
|
index = ret - WAIT_OBJECT_0;
|
|
Assert(index >= 0 && index < win32_numChildren);
|
|
if (!GetExitCodeProcess(win32_childHNDArray[index], &exitCode))
|
|
{
|
|
/*
|
|
* If we get this far, this should never happen, but,
|
|
* then again... No choice other than to assume a
|
|
* catastrophic failure.
|
|
*/
|
|
ereport(FATAL,
|
|
(errmsg_internal("failed to get exit code for child %lu",
|
|
win32_childPIDArray[index])));
|
|
}
|
|
*exitstatus = (int) exitCode;
|
|
return win32_childPIDArray[index];
|
|
}
|
|
}
|
|
|
|
/* No children */
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Note! Code below executes on separate threads, one for
|
|
* each child process created
|
|
*/
|
|
static DWORD WINAPI
|
|
win32_sigchld_waiter(LPVOID param)
|
|
{
|
|
HANDLE procHandle = (HANDLE) param;
|
|
|
|
DWORD r = WaitForSingleObject(procHandle, INFINITE);
|
|
|
|
if (r == WAIT_OBJECT_0)
|
|
pg_queue_signal(SIGCHLD);
|
|
else
|
|
write_stderr("ERROR: failed to wait on child process handle: %d\n",
|
|
(int) GetLastError());
|
|
CloseHandle(procHandle);
|
|
return 0;
|
|
}
|
|
|
|
#endif /* WIN32 */
|