mirror of
https://git.postgresql.org/git/postgresql.git
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1739 lines
40 KiB
C
1739 lines
40 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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* 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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* $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.112 1999/07/16 04:59:38 momjian 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 a few shared memory data structures
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* for the backends. It should at the very least initialize the
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* lock manager.
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*
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* Synchronization:
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* The Postmaster shares memory with the backends and will have to lock
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* the shared memory it accesses. The Postmaster should never block
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* on messages from 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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* Communication:
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*
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*-------------------------------------------------------------------------
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*/
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/* moved here to prevent double define */
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#include <sys/param.h>
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#ifdef HAVE_NETDB_H
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#include <netdb.h>
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#endif
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#include "postgres.h"
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#ifndef MAXHOSTNAMELEN
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#define MAXHOSTNAMELEN 256
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#endif
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#if !defined(NO_UNISTD_H)
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#include <unistd.h>
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#endif /* !NO_UNISTD_H */
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#include <signal.h>
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#include <string.h>
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#include <stdlib.h>
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#include <time.h>
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#ifdef HAVE_LIMITS_H
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#include <limits.h>
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#else
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#include <values.h>
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#endif
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#include <sys/wait.h>
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#include <ctype.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <sys/time.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 <stdio.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 __CYGWIN32__
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#include "getopt.h"
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#endif
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#ifndef HAVE_GETHOSTNAME
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#include "port-protos.h"
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#endif
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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 "storage/fd.h"
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#include "storage/ipc.h"
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#include "storage/proc.h"
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#include "tcop/tcopprot.h"
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#include "utils/trace.h"
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#include "version.h"
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#if !defined(MAXINT)
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#define MAXINT INT_MAX
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#endif
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#define INVALID_SOCK (-1)
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#define ARGV_SIZE 64
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/*
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* Max time in seconds for socket to linger (close() to block) waiting
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* for frontend to retrieve its message from us.
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*/
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/*
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* Info for garbage collection. Whenever a process dies, the Postmaster
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* cleans up after it. Currently, NO information is required for cleanup,
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* but I left this structure around in case that changed.
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*/
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typedef struct bkend
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{
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int 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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Port *MyBackendPort = NULL;
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/* list of active backends. For garbage collection only now. */
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static Dllist *BackendList;
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/* list of ports associated with still open, but incomplete connections */
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static Dllist *PortList;
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static unsigned short PostPortName = 0;
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static short ActiveBackends = FALSE;
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/*
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* This is a boolean indicating that there is at least one backend that
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* is accessing the current shared memory and semaphores. Between the
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* time that we start up, or throw away shared memory segments and start
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* over, and the time we generate the next backend (because we received a
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* connection request), it is false. Other times, it is true.
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*/
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static short shmem_seq = 0;
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/*
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* This is a sequence number that indicates how many times we've had to
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* throw away the shared memory and start over because we doubted its
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* integrity. It starts off at zero and is incremented every time we
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* start over. We use this to ensure that we use a new IPC shared memory
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* key for the new shared memory segment in case the old segment isn't
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* entirely gone yet.
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*
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* The sequence actually cycles back to 0 after 9, so pathologically there
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* could be an IPC failure if 10 sets of backends are all stuck and won't
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* release IPC resources.
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*/
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static IpcMemoryKey ipc_key;
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/*
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* This is the base IPC shared memory key. Other keys are generated by
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* adding to this.
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*/
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static int MaxBackends = DEF_MAXBACKENDS;
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/*
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* MaxBackends is the actual limit on the number of backends we will
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* start. The default is established by configure, but it can be
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* readjusted from 1..MAXBACKENDS with the postmaster -N switch. Note
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* that a larger MaxBackends value will increase the size of the shared
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* memory area as well as cause the postmaster to grab more kernel
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* semaphores, even if you never actually use that many backends.
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*/
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static int NextBackendTag = MAXINT; /* XXX why count down not up? */
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static char *progname = (char *) NULL;
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static char **real_argv;
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static int real_argc;
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/*
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* Default Values
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*/
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static char Execfile[MAXPATHLEN] = "";
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static int ServerSock_INET = INVALID_SOCK; /* stream socket server */
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#ifndef __CYGWIN32__
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static int ServerSock_UNIX = INVALID_SOCK; /* stream socket server */
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#endif
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/*
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* Set by the -o option
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*/
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static char ExtraOptions[MAXPATHLEN] = "";
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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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static bool NetServer = false; /* if not zero, postmaster listen for
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* non-local connections */
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/*
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* GH: For !HAVE_SIGPROCMASK (NEXTSTEP), TRH implemented an
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* alternative interface.
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*/
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#ifdef HAVE_SIGPROCMASK
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static sigset_t oldsigmask,
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newsigmask;
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#else
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static int orgsigmask = sigblock(0);
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#endif
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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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extern char *optarg;
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extern int optind,
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opterr;
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/*
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* postmaster.c - function prototypes
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*/
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static void pmdaemonize(void);
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static Port *ConnCreate(int serverFd);
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static void reset_shared(unsigned short port);
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static void pmdie(SIGNAL_ARGS);
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static void reaper(SIGNAL_ARGS);
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static void dumpstatus(SIGNAL_ARGS);
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static void CleanupProc(int pid, int exitstatus);
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static int DoBackend(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 readStartupPacket(void *arg, PacketLen len, void *pkt);
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static int processCancelRequest(Port *port, PacketLen len, void *pkt);
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static int initMasks(fd_set *rmask, fd_set *wmask);
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static long PostmasterRandom(void);
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static void RandomSalt(char *salt);
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static void SignalChildren(SIGNAL_ARGS);
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static int CountChildren(void);
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#ifdef CYR_RECODE
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void GetCharSetByHost(char *, int, char *);
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#endif
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#ifdef USE_ASSERT_CHECKING
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int assert_enabled = 1;
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#endif
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static void
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checkDataDir(const char *DataDir, bool *DataDirOK)
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{
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if (DataDir == NULL)
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{
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fprintf(stderr, "%s does not know where to find the database system "
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"data. You must specify the directory that contains the "
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"database system either by specifying the -D invocation "
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"option or by setting the PGDATA environment variable.\n\n",
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progname);
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*DataDirOK = false;
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}
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else
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{
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char path[MAXPATHLEN];
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FILE *fp;
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sprintf(path, "%s%cbase%ctemplate1%cpg_class",
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DataDir, SEP_CHAR, SEP_CHAR, SEP_CHAR);
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#ifndef __CYGWIN32__
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fp = AllocateFile(path, "r");
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#else
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fp = AllocateFile(path, "rb");
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#endif
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if (fp == NULL)
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{
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fprintf(stderr, "%s does not find the database system. "
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"Expected to find it "
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"in the PGDATA directory \"%s\", but unable to open file "
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"with pathname \"%s\".\n\n",
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progname, DataDir, path);
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*DataDirOK = false;
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}
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else
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{
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char *reason;
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/* reason ValidatePgVersion failed. NULL if didn't */
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FreeFile(fp);
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ValidatePgVersion(DataDir, &reason);
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if (reason)
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{
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fprintf(stderr,
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"Database system in directory %s "
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"is not compatible with this version of "
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"Postgres, or we are unable to read the "
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"PG_VERSION file. "
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"Explanation from ValidatePgVersion: %s\n\n",
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DataDir, reason);
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free(reason);
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*DataDirOK = false;
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}
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else
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*DataDirOK = true;
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}
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}
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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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extern int NBuffers; /* from buffer/bufmgr.c */
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int opt;
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char *hostName;
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int status;
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int silentflag = 0;
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bool DataDirOK; /* We have a usable PGDATA value */
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char hostbuf[MAXHOSTNAMELEN];
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int nonblank_argc;
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/*
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* We need three params so we can display status. If we don't get
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* them from the user, let's make them ourselves.
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*/
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if (argc < 5)
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{
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int i;
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char *new_argv[6];
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for (i = 0; i < argc; i++)
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new_argv[i] = argv[i];
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for (; i < 5; i++)
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new_argv[i] = "";
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new_argv[5] = NULL;
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if (!Execfile[0] && FindExec(Execfile, argv[0], "postmaster") < 0)
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{
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fprintf(stderr, "%s: could not find postmaster to execute...\n",
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argv[0]);
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exit(1);
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}
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new_argv[0] = Execfile;
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execv(new_argv[0], new_argv);
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/* How did we get here, error! */
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perror(new_argv[0]);
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fprintf(stderr, "PostmasterMain execv failed on %s\n", argv[0]);
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exit(1);
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}
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progname = argv[0];
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real_argv = argv;
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real_argc = argc;
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/*
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* don't process any dummy args we placed at the end for status
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* display
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*/
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for (nonblank_argc = argc; nonblank_argc > 0; nonblank_argc--)
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if (argv[nonblank_argc - 1] != NULL && argv[nonblank_argc - 1][0] != '\0')
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break;
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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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if (!(hostName = getenv("PGHOST")))
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{
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if (gethostname(hostbuf, MAXHOSTNAMELEN) < 0)
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strcpy(hostbuf, "localhost");
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hostName = hostbuf;
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}
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MyProcPid = getpid();
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DataDir = getenv("PGDATA"); /* default value */
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opterr = 0;
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while ((opt = getopt(nonblank_argc, argv, "A:a:B:b:D:dim:MN:no:p:Ss")) != EOF)
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{
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switch (opt)
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{
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case 'A':
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#ifndef USE_ASSERT_CHECKING
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fprintf(stderr, "Assert checking is not enabled\n");
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#else
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/*
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* Pass this option also to each backend.
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*/
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assert_enabled = atoi(optarg);
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strcat(ExtraOptions, " -A ");
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strcat(ExtraOptions, optarg);
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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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/*
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* The number of buffers to create. Setting this option
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* means we have to start each backend with a -B # to make
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* sure they know how many buffers were allocated.
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*/
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NBuffers = atoi(optarg);
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strcat(ExtraOptions, " -B ");
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strcat(ExtraOptions, optarg);
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break;
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case 'b':
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/* Set the backend executable file to use. */
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if (!ValidateBinary(optarg))
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strcpy(Execfile, optarg);
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else
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{
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fprintf(stderr, "%s: invalid backend \"%s\"\n",
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progname, optarg);
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exit(2);
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}
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break;
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case 'D':
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/* Set PGDATA from the command line. */
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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 and the backend
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* servers descended from it.
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*/
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if ((optind < nonblank_argc) && *argv[optind] != '-')
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{
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DebugLvl = atoi(argv[optind]);
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optind++;
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}
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else
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DebugLvl = 1;
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pg_options[TRACE_VERBOSE] = DebugLvl;
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break;
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case 'i':
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NetServer = true;
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break;
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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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/*
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* The max number of backends to start. Can't set to less
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* than 1 or more than compiled-in limit.
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*/
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MaxBackends = atoi(optarg);
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if (MaxBackends < 1)
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MaxBackends = 1;
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if (MaxBackends > MAXBACKENDS)
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MaxBackends = MAXBACKENDS;
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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
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* line -- useful only for debugging.
|
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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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/* Set PGPORT by hand. */
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PostPortName = (unsigned short) atoi(optarg);
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break;
|
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case 'S':
|
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/*
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* Start in 'S'ilent mode (disassociate from controlling
|
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* tty). You may also think of this as 'S'ysV mode since
|
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* it's most badly needed on SysV-derived systems like
|
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* SVR4 and HP-UX.
|
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*/
|
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silentflag = 1;
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break;
|
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case 's':
|
|
|
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/*
|
|
* In the event that some backend dumps core, send
|
|
* SIGSTOP, rather than SIGUSR1, to all its peers. This
|
|
* lets the wily post_hacker collect core dumps from
|
|
* everyone.
|
|
*/
|
|
SendStop = true;
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break;
|
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default:
|
|
/* usage() never returns */
|
|
usage(progname);
|
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break;
|
|
}
|
|
}
|
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|
|
/*
|
|
* Select default values for switches where needed
|
|
*/
|
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if (PostPortName == 0)
|
|
PostPortName = (unsigned short)pq_getport();
|
|
|
|
/*
|
|
* Check for invalid combinations of switches
|
|
*/
|
|
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.
|
|
*/
|
|
fprintf(stderr, "%s: -B must be at least twice -N and at least 16.\n",
|
|
progname);
|
|
exit(1);
|
|
}
|
|
|
|
checkDataDir(DataDir, &DataDirOK); /* issues error messages */
|
|
if (!DataDirOK)
|
|
{
|
|
fprintf(stderr, "No data directory -- can't proceed.\n");
|
|
exit(2);
|
|
}
|
|
|
|
if (!Execfile[0] && FindExec(Execfile, argv[0], "postgres") < 0)
|
|
{
|
|
fprintf(stderr, "%s: could not find backend to execute...\n",
|
|
argv[0]);
|
|
exit(1);
|
|
}
|
|
|
|
if (NetServer)
|
|
{
|
|
status = StreamServerPort(hostName, PostPortName, &ServerSock_INET);
|
|
if (status != STATUS_OK)
|
|
{
|
|
fprintf(stderr, "%s: cannot create INET stream port\n",
|
|
progname);
|
|
exit(1);
|
|
}
|
|
}
|
|
#ifndef __CYGWIN32__
|
|
status = StreamServerPort(NULL, PostPortName, &ServerSock_UNIX);
|
|
if (status != STATUS_OK)
|
|
{
|
|
fprintf(stderr, "%s: cannot create UNIX stream port\n",
|
|
progname);
|
|
exit(1);
|
|
}
|
|
#endif
|
|
/* set up shared memory and semaphores */
|
|
EnableMemoryContext(TRUE);
|
|
reset_shared(PostPortName);
|
|
|
|
/*
|
|
* Initialize the list of active backends. This list is only used for
|
|
* garbage collecting the backend processes.
|
|
*/
|
|
BackendList = DLNewList();
|
|
PortList = DLNewList();
|
|
|
|
if (silentflag)
|
|
pmdaemonize();
|
|
|
|
/*
|
|
* Set up signal handlers for the postmaster process.
|
|
*/
|
|
|
|
pqsignal(SIGHUP, pmdie); /* send SIGHUP, don't die */
|
|
pqsignal(SIGINT, pmdie); /* die */
|
|
pqsignal(SIGQUIT, pmdie); /* send SIGTERM and die */
|
|
pqsignal(SIGTERM, pmdie); /* send SIGTERM,SIGKILL and die */
|
|
pqsignal(SIGPIPE, SIG_IGN); /* ignored */
|
|
pqsignal(SIGUSR1, pmdie); /* send SIGUSR1 and die */
|
|
pqsignal(SIGUSR2, pmdie); /* send SIGUSR2, don't die */
|
|
pqsignal(SIGCHLD, reaper); /* handle child termination */
|
|
pqsignal(SIGTTIN, SIG_IGN); /* ignored */
|
|
pqsignal(SIGTTOU, SIG_IGN); /* ignored */
|
|
pqsignal(SIGWINCH, dumpstatus); /* dump port status */
|
|
|
|
status = ServerLoop();
|
|
|
|
ExitPostmaster(status != STATUS_OK);
|
|
return 0; /* not reached */
|
|
}
|
|
|
|
static void
|
|
pmdaemonize(void)
|
|
{
|
|
int i;
|
|
|
|
if (fork())
|
|
_exit(0);
|
|
/* 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)
|
|
{
|
|
fprintf(stderr, "%s: ", progname);
|
|
perror("cannot disassociate from controlling TTY");
|
|
exit(1);
|
|
}
|
|
#endif
|
|
#ifndef __CYGWIN32__
|
|
i = open(NULL_DEV, O_RDWR);
|
|
#else
|
|
i = open(NULL_DEV, O_RDWR | O_BINARY);
|
|
#endif
|
|
dup2(i, 0);
|
|
dup2(i, 1);
|
|
dup2(i, 2);
|
|
close(i);
|
|
}
|
|
|
|
static void
|
|
usage(const char *progname)
|
|
{
|
|
fprintf(stderr, "usage: %s [options]\n", progname);
|
|
#ifdef USE_ASSERT_CHECKING
|
|
fprintf(stderr, "\t-A [1|0]\tenable/disable runtime assert checking\n");
|
|
#endif
|
|
fprintf(stderr, "\t-B nbufs\tset number of shared buffers\n");
|
|
fprintf(stderr, "\t-D datadir\tset data directory\n");
|
|
fprintf(stderr, "\t-S \t\tsilent mode (disassociate from tty)\n");
|
|
fprintf(stderr, "\t-a system\tuse this authentication system\n");
|
|
fprintf(stderr, "\t-b backend\tuse a specific backend server executable\n");
|
|
fprintf(stderr, "\t-d [1|2|3]\tset debugging level\n");
|
|
fprintf(stderr, "\t-i \t\tlisten on TCP/IP sockets as well as Unix domain socket\n");
|
|
fprintf(stderr, "\t-N nprocs\tset max number of backends (1..%d, default %d)\n",
|
|
MAXBACKENDS, DEF_MAXBACKENDS);
|
|
fprintf(stderr, "\t-n \t\tdon't reinitialize shared memory after abnormal exit\n");
|
|
fprintf(stderr, "\t-o option\tpass 'option' to each backend servers\n");
|
|
fprintf(stderr, "\t-p port\tspecify port for postmaster to listen on\n");
|
|
fprintf(stderr, "\t-s \t\tsend SIGSTOP to all backend servers if one dies\n");
|
|
exit(1);
|
|
}
|
|
|
|
static int
|
|
ServerLoop(void)
|
|
{
|
|
fd_set readmask,
|
|
writemask;
|
|
int nSockets;
|
|
Dlelem *curr;
|
|
struct timeval now,
|
|
later;
|
|
struct timezone tz;
|
|
|
|
gettimeofday(&now, &tz);
|
|
|
|
nSockets = initMasks(&readmask, &writemask);
|
|
|
|
#ifdef HAVE_SIGPROCMASK
|
|
sigprocmask(0, NULL, &oldsigmask);
|
|
sigemptyset(&newsigmask);
|
|
sigaddset(&newsigmask, SIGCHLD);
|
|
#endif
|
|
|
|
for (;;)
|
|
{
|
|
Port *port;
|
|
fd_set rmask,
|
|
wmask;
|
|
|
|
#ifdef HAVE_SIGPROCMASK
|
|
sigprocmask(SIG_SETMASK, &oldsigmask, 0);
|
|
#else
|
|
sigsetmask(orgsigmask);
|
|
#endif
|
|
|
|
memmove((char *) &rmask, (char *) &readmask, sizeof(fd_set));
|
|
memmove((char *) &wmask, (char *) &writemask, sizeof(fd_set));
|
|
if (select(nSockets, &rmask, &wmask, (fd_set *) NULL,
|
|
(struct timeval *) NULL) < 0)
|
|
{
|
|
if (errno == EINTR)
|
|
continue;
|
|
fprintf(stderr, "%s: ServerLoop: select failed: %s\n",
|
|
progname, strerror(errno));
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
/*
|
|
* 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 'now'. On the
|
|
* off chance that the result is 0, we loop until it isn't.
|
|
*/
|
|
random_seed = now.tv_usec ^
|
|
((later.tv_usec << 16) |
|
|
((later.tv_usec >> 16) & 0xffff));
|
|
}
|
|
|
|
/*
|
|
* [TRH] To avoid race conditions, block SIGCHLD signals while we
|
|
* are handling the request. (both reaper() and ConnCreate()
|
|
* manipulate the BackEnd list, and reaper() calls free() which is
|
|
* usually non-reentrant.)
|
|
*/
|
|
#ifdef HAVE_SIGPROCMASK
|
|
sigprocmask(SIG_BLOCK, &newsigmask, &oldsigmask);
|
|
#else
|
|
sigblock(sigmask(SIGCHLD)); /* XXX[TRH] portability */
|
|
#endif
|
|
|
|
/* new connection pending on our well-known port's socket */
|
|
|
|
#ifndef __CYGWIN32__
|
|
if (ServerSock_UNIX != INVALID_SOCK &&
|
|
FD_ISSET(ServerSock_UNIX, &rmask) &&
|
|
(port = ConnCreate(ServerSock_UNIX)) != NULL)
|
|
PacketReceiveSetup(&port->pktInfo,
|
|
readStartupPacket,
|
|
(void *) port);
|
|
#endif
|
|
|
|
if (ServerSock_INET != INVALID_SOCK &&
|
|
FD_ISSET(ServerSock_INET, &rmask) &&
|
|
(port = ConnCreate(ServerSock_INET)) != NULL)
|
|
PacketReceiveSetup(&port->pktInfo,
|
|
readStartupPacket,
|
|
(void *) port);
|
|
|
|
/* Build up new masks for select(). */
|
|
|
|
nSockets = initMasks(&readmask, &writemask);
|
|
|
|
curr = DLGetHead(PortList);
|
|
|
|
while (curr)
|
|
{
|
|
Port *port = (Port *) DLE_VAL(curr);
|
|
int status = STATUS_OK;
|
|
Dlelem *next;
|
|
|
|
if (FD_ISSET(port->sock, &rmask))
|
|
{
|
|
if (DebugLvl > 1)
|
|
fprintf(stderr, "%s: ServerLoop:\t\thandling reading %d\n",
|
|
progname, port->sock);
|
|
|
|
if (PacketReceiveFragment(&port->pktInfo, port->sock) != STATUS_OK)
|
|
status = STATUS_ERROR;
|
|
}
|
|
|
|
if (FD_ISSET(port->sock, &wmask))
|
|
{
|
|
if (DebugLvl > 1)
|
|
fprintf(stderr, "%s: ServerLoop:\t\thandling writing %d\n",
|
|
progname, port->sock);
|
|
|
|
if (PacketSendFragment(&port->pktInfo, port->sock) != STATUS_OK)
|
|
status = STATUS_ERROR;
|
|
}
|
|
|
|
/* Get this before the connection might be closed. */
|
|
|
|
next = DLGetSucc(curr);
|
|
|
|
/*
|
|
* If there is no error and no outstanding data transfer going
|
|
* on, then the authentication handshake must be complete to
|
|
* the postmaster's satisfaction. So, start the backend.
|
|
*/
|
|
|
|
if (status == STATUS_OK && port->pktInfo.state == Idle)
|
|
{
|
|
/* Can't start backend if max backend count is exceeded. */
|
|
if (CountChildren() >= MaxBackends)
|
|
PacketSendError(&port->pktInfo,
|
|
"Sorry, too many clients already");
|
|
else
|
|
{
|
|
|
|
/*
|
|
* If the backend start fails then keep the connection
|
|
* open to report it. Otherwise, pretend there is an
|
|
* error to close the connection which will now be
|
|
* managed by the backend.
|
|
*/
|
|
if (BackendStartup(port) != STATUS_OK)
|
|
PacketSendError(&port->pktInfo,
|
|
"Backend startup failed");
|
|
else
|
|
status = STATUS_ERROR;
|
|
}
|
|
}
|
|
|
|
/* Close the connection if required. */
|
|
|
|
if (status != STATUS_OK)
|
|
{
|
|
StreamClose(port->sock);
|
|
DLRemove(curr);
|
|
free(port);
|
|
DLFreeElem(curr);
|
|
}
|
|
else
|
|
{
|
|
/* Set the masks for this connection. */
|
|
|
|
if (nSockets <= port->sock)
|
|
nSockets = port->sock + 1;
|
|
|
|
if (port->pktInfo.state == WritingPacket)
|
|
FD_SET(port->sock, &writemask);
|
|
else
|
|
FD_SET(port->sock, &readmask);
|
|
}
|
|
|
|
curr = next;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Initialise the read and write masks for select() for the well-known ports
|
|
* we are listening on. Return the number of sockets to listen on.
|
|
*/
|
|
|
|
static int
|
|
initMasks(fd_set *rmask, fd_set *wmask)
|
|
{
|
|
int nsocks = -1;
|
|
|
|
FD_ZERO(rmask);
|
|
FD_ZERO(wmask);
|
|
|
|
#ifndef __CYGWIN32__
|
|
if (ServerSock_UNIX != INVALID_SOCK)
|
|
{
|
|
FD_SET(ServerSock_UNIX, rmask);
|
|
|
|
if (ServerSock_UNIX > nsocks)
|
|
nsocks = ServerSock_UNIX;
|
|
}
|
|
#endif
|
|
|
|
if (ServerSock_INET != INVALID_SOCK)
|
|
{
|
|
FD_SET(ServerSock_INET, rmask);
|
|
|
|
if (ServerSock_INET > nsocks)
|
|
nsocks = ServerSock_INET;
|
|
}
|
|
|
|
return nsocks + 1;
|
|
}
|
|
|
|
|
|
/*
|
|
* Called when the startup packet has been read.
|
|
*/
|
|
|
|
static int
|
|
readStartupPacket(void *arg, PacketLen len, void *pkt)
|
|
{
|
|
Port *port;
|
|
StartupPacket *si;
|
|
|
|
port = (Port *) arg;
|
|
si = (StartupPacket *) pkt;
|
|
|
|
/*
|
|
* The first field is either a protocol version number or a special
|
|
* request code.
|
|
*/
|
|
|
|
port->proto = ntohl(si->protoVersion);
|
|
|
|
if (port->proto == CANCEL_REQUEST_CODE)
|
|
return processCancelRequest(port, len, pkt);
|
|
|
|
/* Could add additional special packet types here */
|
|
|
|
/* Check we can handle the protocol the frontend is using. */
|
|
|
|
if (PG_PROTOCOL_MAJOR(port->proto) < PG_PROTOCOL_MAJOR(PG_PROTOCOL_EARLIEST) ||
|
|
PG_PROTOCOL_MAJOR(port->proto) > PG_PROTOCOL_MAJOR(PG_PROTOCOL_LATEST) ||
|
|
(PG_PROTOCOL_MAJOR(port->proto) == PG_PROTOCOL_MAJOR(PG_PROTOCOL_LATEST) &&
|
|
PG_PROTOCOL_MINOR(port->proto) > PG_PROTOCOL_MINOR(PG_PROTOCOL_LATEST)))
|
|
{
|
|
PacketSendError(&port->pktInfo, "Unsupported frontend protocol.");
|
|
return STATUS_OK; /* don't close the connection yet */
|
|
}
|
|
|
|
/*
|
|
* Get the parameters from the startup packet as C strings. The
|
|
* packet destination was cleared first so a short packet has zeros
|
|
* silently added and a long packet is silently truncated.
|
|
*/
|
|
|
|
StrNCpy(port->database, si->database, sizeof(port->database) - 1);
|
|
StrNCpy(port->user, si->user, sizeof(port->user) - 1);
|
|
StrNCpy(port->options, si->options, sizeof(port->options) - 1);
|
|
StrNCpy(port->tty, si->tty, sizeof(port->tty) - 1);
|
|
|
|
/* The database defaults to the user name. */
|
|
|
|
if (port->database[0] == '\0')
|
|
StrNCpy(port->database, si->user, sizeof(port->database) - 1);
|
|
|
|
/* Check a user name was given. */
|
|
|
|
if (port->user[0] == '\0')
|
|
{
|
|
PacketSendError(&port->pktInfo,
|
|
"No Postgres username specified in startup packet.");
|
|
return STATUS_OK; /* don't close the connection yet */
|
|
}
|
|
|
|
/* Start the authentication itself. */
|
|
|
|
be_recvauth(port);
|
|
|
|
return STATUS_OK; /* don't close the connection yet */
|
|
}
|
|
|
|
|
|
/*
|
|
* The client has sent a cancel request packet, not a normal
|
|
* start-a-new-backend packet. Perform the necessary processing.
|
|
* Note that in any case, we return STATUS_ERROR to close the
|
|
* connection immediately. Nothing is sent back to the client.
|
|
*/
|
|
|
|
static int
|
|
processCancelRequest(Port *port, PacketLen len, void *pkt)
|
|
{
|
|
CancelRequestPacket *canc = (CancelRequestPacket *) pkt;
|
|
int backendPID;
|
|
long cancelAuthCode;
|
|
Dlelem *curr;
|
|
Backend *bp;
|
|
|
|
backendPID = (int) ntohl(canc->backendPID);
|
|
cancelAuthCode = (long) ntohl(canc->cancelAuthCode);
|
|
|
|
/* See if we have a matching backend */
|
|
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
bp = (Backend *) DLE_VAL(curr);
|
|
if (bp->pid == backendPID)
|
|
{
|
|
if (bp->cancel_key == cancelAuthCode)
|
|
{
|
|
/* Found a match; signal that backend to cancel current op */
|
|
if (DebugLvl)
|
|
fprintf(stderr, "%s: processCancelRequest: sending SIGINT to process %d\n",
|
|
progname, bp->pid);
|
|
kill(bp->pid, SIGINT);
|
|
}
|
|
else
|
|
{
|
|
/* Right PID, wrong key: no way, Jose */
|
|
if (DebugLvl)
|
|
fprintf(stderr, "%s: processCancelRequest: bad key in cancel request for process %d\n",
|
|
progname, bp->pid);
|
|
}
|
|
return STATUS_ERROR;
|
|
}
|
|
}
|
|
|
|
/* No matching backend */
|
|
if (DebugLvl)
|
|
fprintf(stderr, "%s: processCancelRequest: bad PID in cancel request for process %d\n",
|
|
progname, backendPID);
|
|
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
|
|
/*
|
|
* ConnCreate -- create a local connection data structure
|
|
*/
|
|
static Port *
|
|
ConnCreate(int serverFd)
|
|
{
|
|
Port *port;
|
|
|
|
|
|
if (!(port = (Port *) calloc(1, sizeof(Port))))
|
|
{
|
|
fprintf(stderr, "%s: ConnCreate: malloc failed\n",
|
|
progname);
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
if (StreamConnection(serverFd, port) != STATUS_OK)
|
|
{
|
|
StreamClose(port->sock);
|
|
free(port);
|
|
port = NULL;
|
|
}
|
|
else
|
|
{
|
|
DLAddHead(PortList, DLNewElem(port));
|
|
RandomSalt(port->salt);
|
|
port->pktInfo.state = Idle;
|
|
}
|
|
|
|
return port;
|
|
}
|
|
|
|
/*
|
|
* reset_shared -- reset shared memory and semaphores
|
|
*/
|
|
static void
|
|
reset_shared(unsigned short port)
|
|
{
|
|
ipc_key = port * 1000 + shmem_seq * 100;
|
|
CreateSharedMemoryAndSemaphores(ipc_key, MaxBackends);
|
|
ActiveBackends = FALSE;
|
|
shmem_seq += 1;
|
|
if (shmem_seq >= 10)
|
|
shmem_seq -= 10;
|
|
}
|
|
|
|
/*
|
|
* pmdie -- signal handler for cleaning up after a kill signal.
|
|
*/
|
|
static void
|
|
pmdie(SIGNAL_ARGS)
|
|
{
|
|
int i;
|
|
|
|
TPRINTF(TRACE_VERBOSE, "pmdie %d", postgres_signal_arg);
|
|
|
|
/*
|
|
* Kill self and/or children processes depending on signal number.
|
|
*/
|
|
switch (postgres_signal_arg)
|
|
{
|
|
case SIGHUP:
|
|
/* Send SIGHUP to all children (update options flags) */
|
|
SignalChildren(SIGHUP);
|
|
/* Don't die */
|
|
return;
|
|
case SIGINT:
|
|
/* Die without killing children */
|
|
break;
|
|
case SIGQUIT:
|
|
/* Shutdown all children with SIGTERM */
|
|
SignalChildren(SIGTERM);
|
|
/* Don't die */
|
|
return;
|
|
case SIGTERM:
|
|
/* Shutdown all children with SIGTERM and SIGKILL, then die */
|
|
SignalChildren(SIGTERM);
|
|
for (i = 0; i < 10; i++)
|
|
{
|
|
if (!DLGetHead(BackendList))
|
|
break;
|
|
sleep(1);
|
|
}
|
|
if (DLGetHead(BackendList))
|
|
SignalChildren(SIGKILL);
|
|
break;
|
|
case SIGUSR1:
|
|
/* Quick die all children with SIGUSR1 and die */
|
|
SignalChildren(SIGUSR1);
|
|
break;
|
|
case SIGUSR2:
|
|
/* Send SIGUSR2 to all children (AsyncNotifyHandler) */
|
|
SignalChildren(SIGUSR2);
|
|
/* Don't die */
|
|
return;
|
|
}
|
|
|
|
/* exit postmaster */
|
|
proc_exit(0);
|
|
}
|
|
|
|
/*
|
|
* Reaper -- signal handler to cleanup after a backend (child) dies.
|
|
*/
|
|
static void
|
|
reaper(SIGNAL_ARGS)
|
|
{
|
|
/* GH: replace waitpid for !HAVE_WAITPID. Does this work ? */
|
|
#ifdef HAVE_WAITPID
|
|
int status; /* backend exit status */
|
|
|
|
#else
|
|
union wait statusp; /* backend exit status */
|
|
|
|
#endif
|
|
int pid; /* process id of dead backend */
|
|
|
|
if (DebugLvl)
|
|
fprintf(stderr, "%s: reaping dead processes...\n",
|
|
progname);
|
|
#ifdef HAVE_WAITPID
|
|
while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
|
|
{
|
|
CleanupProc(pid, status);
|
|
pqsignal(SIGCHLD, reaper);
|
|
}
|
|
#else
|
|
while ((pid = wait3(&statusp, WNOHANG, NULL)) > 0)
|
|
{
|
|
CleanupProc(pid, statusp.w_status);
|
|
pqsignal(SIGCHLD, reaper);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* CleanupProc -- cleanup after terminated backend.
|
|
*
|
|
* Remove all local state associated with backend.
|
|
*
|
|
* Dillon's note: should log child's exit status in the system log.
|
|
*/
|
|
static void
|
|
CleanupProc(int pid,
|
|
int exitstatus) /* child's exit status. */
|
|
{
|
|
Dlelem *prev,
|
|
*curr;
|
|
Backend *bp;
|
|
int sig;
|
|
|
|
if (DebugLvl)
|
|
{
|
|
fprintf(stderr, "%s: CleanupProc: pid %d exited with status %d\n",
|
|
progname, 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)
|
|
{
|
|
curr = DLGetHead(BackendList);
|
|
while (curr)
|
|
{
|
|
bp = (Backend *) DLE_VAL(curr);
|
|
if (bp->pid == pid)
|
|
{
|
|
DLRemove(curr);
|
|
free(bp);
|
|
DLFreeElem(curr);
|
|
break;
|
|
}
|
|
curr = DLGetSucc(curr);
|
|
}
|
|
|
|
ProcRemove(pid);
|
|
|
|
return;
|
|
}
|
|
|
|
curr = DLGetHead(BackendList);
|
|
while (curr)
|
|
{
|
|
bp = (Backend *) DLE_VAL(curr);
|
|
|
|
/* -----------------
|
|
* SIGUSR1 is the special signal that says exit
|
|
* without proc_exit and let the user know what's going on.
|
|
* ProcSemaphoreKill() cleans up the backends semaphore. If
|
|
* SendStop is set (-s on command line), then we send a SIGSTOP so
|
|
* that we can core dumps from all backends by hand.
|
|
* -----------------
|
|
*/
|
|
sig = (SendStop) ? SIGSTOP : SIGUSR1;
|
|
if (bp->pid != pid)
|
|
{
|
|
if (DebugLvl)
|
|
fprintf(stderr, "%s: CleanupProc: sending %s to process %d\n",
|
|
progname,
|
|
(sig == SIGUSR1)
|
|
? "SIGUSR1" : "SIGSTOP",
|
|
bp->pid);
|
|
kill(bp->pid, sig);
|
|
}
|
|
ProcRemove(bp->pid);
|
|
|
|
prev = DLGetPred(curr);
|
|
DLRemove(curr);
|
|
free(bp);
|
|
DLFreeElem(curr);
|
|
if (!prev)
|
|
{ /* removed head */
|
|
curr = DLGetHead(BackendList);
|
|
continue;
|
|
}
|
|
curr = DLGetSucc(prev);
|
|
}
|
|
|
|
/*
|
|
* Nothing up my sleeve here, ActiveBackends means that since the last
|
|
* time we recreated shared memory and sems another frontend has
|
|
* requested and received a connection and I have forked off another
|
|
* backend. This prevents me from reinitializing shared stuff more
|
|
* than once for the set of backends that caused the failure and were
|
|
* killed off.
|
|
*/
|
|
if (ActiveBackends == TRUE && Reinit)
|
|
{
|
|
if (DebugLvl)
|
|
fprintf(stderr, "%s: CleanupProc: reinitializing shared memory and semaphores\n",
|
|
progname);
|
|
shmem_exit(0);
|
|
reset_shared(PostPortName);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Send a signal to all chidren processes.
|
|
*/
|
|
static void
|
|
SignalChildren(int signal)
|
|
{
|
|
Dlelem *curr,
|
|
*next;
|
|
Backend *bp;
|
|
int mypid = getpid();
|
|
|
|
curr = DLGetHead(BackendList);
|
|
while (curr)
|
|
{
|
|
next = DLGetSucc(curr);
|
|
bp = (Backend *) DLE_VAL(curr);
|
|
|
|
if (bp->pid != mypid)
|
|
{
|
|
TPRINTF(TRACE_VERBOSE,
|
|
"SignalChildren: sending signal %d to process %d",
|
|
signal, bp->pid);
|
|
kill(bp->pid, signal);
|
|
}
|
|
|
|
curr = next;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* BackendStartup -- start backend process
|
|
*
|
|
* returns: STATUS_ERROR if the fork/exec failed, STATUS_OK
|
|
* otherwise.
|
|
*
|
|
*/
|
|
static int
|
|
BackendStartup(Port *port)
|
|
{
|
|
Backend *bn; /* for backend cleanup */
|
|
int pid,
|
|
i;
|
|
|
|
#ifdef CYR_RECODE
|
|
#define NR_ENVIRONMENT_VBL 6
|
|
char ChTable[80];
|
|
|
|
#else
|
|
#define NR_ENVIRONMENT_VBL 5
|
|
#endif
|
|
|
|
static char envEntry[NR_ENVIRONMENT_VBL][2 * ARGV_SIZE];
|
|
|
|
for (i = 0; i < NR_ENVIRONMENT_VBL; ++i)
|
|
MemSet(envEntry[i], 0, 2 * ARGV_SIZE);
|
|
|
|
/*
|
|
* Set up the necessary environment variables for the backend This
|
|
* should really be some sort of message....
|
|
*/
|
|
sprintf(envEntry[0], "POSTPORT=%d", PostPortName);
|
|
putenv(envEntry[0]);
|
|
sprintf(envEntry[1], "POSTID=%d", NextBackendTag);
|
|
putenv(envEntry[1]);
|
|
sprintf(envEntry[2], "PG_USER=%s", port->user);
|
|
putenv(envEntry[2]);
|
|
if (!getenv("PGDATA"))
|
|
{
|
|
sprintf(envEntry[3], "PGDATA=%s", DataDir);
|
|
putenv(envEntry[3]);
|
|
}
|
|
sprintf(envEntry[4], "IPC_KEY=%d", ipc_key);
|
|
putenv(envEntry[4]);
|
|
|
|
#ifdef CYR_RECODE
|
|
GetCharSetByHost(ChTable, port->raddr.in.sin_addr.s_addr, DataDir);
|
|
if (*ChTable != '\0')
|
|
{
|
|
sprintf(envEntry[5], "PG_RECODETABLE=%s", ChTable);
|
|
putenv(envEntry[5]);
|
|
}
|
|
#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();
|
|
|
|
if (DebugLvl > 2)
|
|
{
|
|
char **p;
|
|
extern char **environ;
|
|
|
|
fprintf(stderr, "%s: BackendStartup: environ dump:\n",
|
|
progname);
|
|
fprintf(stderr, "-----------------------------------------\n");
|
|
for (p = environ; *p; ++p)
|
|
fprintf(stderr, "\t%s\n", *p);
|
|
fprintf(stderr, "-----------------------------------------\n");
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
|
|
if ((pid = fork()) == 0)
|
|
{ /* child */
|
|
if (DoBackend(port))
|
|
{
|
|
fprintf(stderr, "%s child[%d]: BackendStartup: backend startup failed\n",
|
|
progname, (int) getpid());
|
|
exit(1);
|
|
}
|
|
else
|
|
exit(0);
|
|
}
|
|
|
|
/* in parent */
|
|
if (pid < 0)
|
|
{
|
|
fprintf(stderr, "%s: BackendStartup: fork failed: %s\n",
|
|
progname, strerror(errno));
|
|
return STATUS_ERROR;
|
|
}
|
|
|
|
if (DebugLvl)
|
|
fprintf(stderr, "%s: BackendStartup: pid %d user %s db %s socket %d\n",
|
|
progname, pid, port->user, port->database,
|
|
port->sock);
|
|
|
|
/* Generate a new backend tag for every backend we start */
|
|
|
|
/*
|
|
* XXX theoretically this could wrap around, if you have the patience
|
|
* to start 2^31 backends ...
|
|
*/
|
|
NextBackendTag -= 1;
|
|
|
|
/*
|
|
* Everything's been successful, it's safe to add this backend to our
|
|
* list of backends.
|
|
*/
|
|
if (!(bn = (Backend *) calloc(1, sizeof(Backend))))
|
|
{
|
|
fprintf(stderr, "%s: BackendStartup: malloc failed\n",
|
|
progname);
|
|
ExitPostmaster(1);
|
|
}
|
|
|
|
bn->pid = pid;
|
|
bn->cancel_key = MyCancelKey;
|
|
DLAddHead(BackendList, DLNewElem(bn));
|
|
|
|
ActiveBackends = TRUE;
|
|
|
|
return STATUS_OK;
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
int i = *argcp;
|
|
|
|
while (s && *s)
|
|
{
|
|
while (isspace(*s))
|
|
++s;
|
|
if (*s == '\0')
|
|
break;
|
|
argv[i++] = s;
|
|
while (*s && !isspace(*s))
|
|
++s;
|
|
if (*s)
|
|
*s++ = '\0';
|
|
}
|
|
|
|
*argcp = i;
|
|
}
|
|
|
|
/*
|
|
* DoBackend -- set up the backend's argument list and invoke backend main().
|
|
*
|
|
* This used to perform an execv() but we no longer exec the backend;
|
|
* it's the same executable as the postmaster.
|
|
*
|
|
* returns:
|
|
* Shouldn't return at all.
|
|
* If PostgresMain() fails, return status.
|
|
*/
|
|
static int
|
|
DoBackend(Port *port)
|
|
{
|
|
char *av[ARGV_SIZE * 2];
|
|
int ac = 0;
|
|
char execbuf[MAXPATHLEN];
|
|
char debugbuf[ARGV_SIZE];
|
|
char protobuf[ARGV_SIZE];
|
|
char dbbuf[ARGV_SIZE];
|
|
char optbuf[ARGV_SIZE];
|
|
char ttybuf[ARGV_SIZE];
|
|
int i;
|
|
struct timeval now;
|
|
struct timezone tz;
|
|
|
|
/*
|
|
* Let's clean up ourselves as the postmaster child
|
|
*/
|
|
|
|
/* We don't want the postmaster's proc_exit() handlers */
|
|
on_exit_reset();
|
|
|
|
/* ----------------
|
|
* register signal handlers.
|
|
* Thanks to the postmaster, these are currently blocked.
|
|
* ----------------
|
|
*/
|
|
pqsignal(SIGINT, die);
|
|
|
|
pqsignal(SIGHUP, die);
|
|
pqsignal(SIGTERM, die);
|
|
pqsignal(SIGPIPE, die);
|
|
pqsignal(SIGUSR1, quickdie);
|
|
pqsignal(SIGUSR2, Async_NotifyHandler);
|
|
pqsignal(SIGFPE, FloatExceptionHandler);
|
|
|
|
pqsignal(SIGCHLD, SIG_DFL);
|
|
pqsignal(SIGTTIN, SIG_DFL);
|
|
pqsignal(SIGTTOU, SIG_DFL);
|
|
pqsignal(SIGCONT, SIG_DFL);
|
|
|
|
/* OK, let's unblock our signals, all together now... */
|
|
sigprocmask(SIG_SETMASK, &oldsigmask, 0);
|
|
|
|
/* Close the postmaster sockets */
|
|
if (NetServer)
|
|
StreamClose(ServerSock_INET);
|
|
#ifndef __CYGWIN32__
|
|
StreamClose(ServerSock_UNIX);
|
|
#endif
|
|
|
|
/* Save port etc. for ps status */
|
|
MyProcPort = port;
|
|
|
|
MyProcPid = getpid();
|
|
|
|
/*
|
|
* 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(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.
|
|
* ----------------
|
|
*/
|
|
|
|
StrNCpy(execbuf, Execfile, MAXPATHLEN);
|
|
av[ac++] = execbuf;
|
|
|
|
/*
|
|
* We need to set our argv[0] to an absolute path name because some
|
|
* OS's use this for dynamic loading, like BSDI. Without it, when we
|
|
* change directories to the database dir, the dynamic loader can't
|
|
* find the base executable and fails. Another advantage is that this
|
|
* changes the 'ps' displayed process name on some platforms. It does
|
|
* on BSDI. That's a big win.
|
|
*/
|
|
|
|
#ifndef linux
|
|
|
|
/*
|
|
* This doesn't work on linux and overwrites the only valid pointer to
|
|
* the argv buffer. See PS_INIT_STATUS macro.
|
|
*/
|
|
real_argv[0] = Execfile;
|
|
#endif
|
|
|
|
/*
|
|
* Pass the requested debugging level along to the backend. We
|
|
* decrement by one; level one debugging in the postmaster traces
|
|
* postmaster connection activity, and levels two and higher are
|
|
* passed along to the backend. This allows us to watch only the
|
|
* postmaster or the postmaster and the backend.
|
|
*/
|
|
if (DebugLvl > 1)
|
|
{
|
|
sprintf(debugbuf, "-d%d", DebugLvl);
|
|
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 since we are now in the child process; this won't
|
|
* change the postmaster's copy.)
|
|
*/
|
|
split_opts(av, &ac, ExtraOptions);
|
|
|
|
/* Tell the backend what protocol the frontend is using. */
|
|
sprintf(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";
|
|
|
|
StrNCpy(dbbuf, port->database, ARGV_SIZE);
|
|
av[ac++] = dbbuf;
|
|
|
|
/*
|
|
* Pass the (insecure) option switches from the connection request.
|
|
*/
|
|
StrNCpy(optbuf, port->options, ARGV_SIZE);
|
|
split_opts(av, &ac, optbuf);
|
|
|
|
/*
|
|
* Pass the (insecure) debug output file request.
|
|
*
|
|
* NOTE: currently, this is useless code, since the backend will not
|
|
* honor an insecure -o switch. I left it here since the backend
|
|
* could be modified to allow insecure -o, given adequate checking
|
|
* that the specified filename is something safe to write on.
|
|
*/
|
|
if (port->tty[0])
|
|
{
|
|
StrNCpy(ttybuf, port->tty, ARGV_SIZE);
|
|
av[ac++] = "-o";
|
|
av[ac++] = ttybuf;
|
|
}
|
|
|
|
av[ac] = (char *) NULL;
|
|
|
|
if (DebugLvl > 1)
|
|
{
|
|
fprintf(stderr, "%s child[%d]: starting with (",
|
|
progname, MyProcPid);
|
|
for (i = 0; i < ac; ++i)
|
|
fprintf(stderr, "%s ", av[i]);
|
|
fprintf(stderr, ")\n");
|
|
}
|
|
|
|
return (PostgresMain(ac, av, real_argc, real_argv));
|
|
}
|
|
|
|
/*
|
|
* ExitPostmaster -- cleanup
|
|
*/
|
|
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.
|
|
*/
|
|
if (ServerSock_INET != INVALID_SOCK)
|
|
StreamClose(ServerSock_INET);
|
|
#ifndef __CYGWIN32__
|
|
if (ServerSock_UNIX != INVALID_SOCK)
|
|
StreamClose(ServerSock_UNIX);
|
|
#endif
|
|
proc_exit(status);
|
|
}
|
|
|
|
static void
|
|
dumpstatus(SIGNAL_ARGS)
|
|
{
|
|
Dlelem *curr = DLGetHead(PortList);
|
|
|
|
while (curr)
|
|
{
|
|
Port *port = DLE_VAL(curr);
|
|
|
|
fprintf(stderr, "%s: dumpstatus:\n", progname);
|
|
fprintf(stderr, "\tsock %d\n", port->sock);
|
|
curr = DLGetSucc(curr);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* CharRemap
|
|
*/
|
|
static char
|
|
CharRemap(long int 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 *salt)
|
|
{
|
|
long rand = PostmasterRandom();
|
|
|
|
*salt = CharRemap(rand % 62);
|
|
*(salt + 1) = CharRemap(rand / 62);
|
|
}
|
|
|
|
/*
|
|
* PostmasterRandom
|
|
*/
|
|
static long
|
|
PostmasterRandom(void)
|
|
{
|
|
|
|
static bool initialized = false;
|
|
|
|
if (!initialized)
|
|
{
|
|
Assert(random_seed != 0 && !IsUnderPostmaster);
|
|
srandom(random_seed);
|
|
initialized = true;
|
|
}
|
|
|
|
return random() ^ random_seed;
|
|
}
|
|
|
|
/*
|
|
* Count up number of child processes.
|
|
*/
|
|
static int
|
|
CountChildren(void)
|
|
{
|
|
Dlelem *curr;
|
|
Backend *bp;
|
|
int mypid = getpid();
|
|
int cnt = 0;
|
|
|
|
for (curr = DLGetHead(BackendList); curr; curr = DLGetSucc(curr))
|
|
{
|
|
bp = (Backend *) DLE_VAL(curr);
|
|
if (bp->pid != mypid)
|
|
cnt++;
|
|
}
|
|
return cnt;
|
|
}
|