#include "lib/ilist.h"
#include "miscadmin.h"

Include dependency graph for postmaster.h:

This graph shows which files directly or indirectly include this file:

Data Structures
struct	PMChild

Macros
#define	POSTMASTER_FD_WATCH

#define	POSTMASTER_FD_OWN 1 /* kept open by postmaster only */

Typedefs
typedef enum DispatchOption	DispatchOption

Enumerations
enum	DispatchOption { DISPATCH_CHECK , DISPATCH_BOOT , DISPATCH_FORKCHILD , DISPATCH_DESCRIBE_CONFIG , DISPATCH_SINGLE , DISPATCH_POSTMASTER }

Functions
pg_noreturn void	PostmasterMain (int argc, char *argv[])

void	ClosePostmasterPorts (bool am_syslogger)

void	InitProcessGlobals (void)

int	MaxLivePostmasterChildren (void)

bool	PostmasterMarkPIDForWorkerNotify (int)

pid_t	postmaster_child_launch (BackendType child_type, int child_slot, void startup_data, size_t startup_data_len, struct ClientSocket client_sock)

const char *	PostmasterChildName (BackendType child_type)

void	InitPostmasterChildSlots (void)

PMChild *	AssignPostmasterChildSlot (BackendType btype)

PMChild *	AllocDeadEndChild (void)

bool	ReleasePostmasterChildSlot (PMChild *pmchild)

PMChild *	FindPostmasterChildByPid (int pid)

DispatchOption	parse_dispatch_option (const char *name)

Variables
PGDLLIMPORT bool	EnableSSL

PGDLLIMPORT int	SuperuserReservedConnections

PGDLLIMPORT int	ReservedConnections

PGDLLIMPORT int	PostPortNumber

PGDLLIMPORT int	Unix_socket_permissions

PGDLLIMPORT char *	Unix_socket_group

PGDLLIMPORT char *	Unix_socket_directories

PGDLLIMPORT char *	ListenAddresses

PGDLLIMPORT bool	ClientAuthInProgress

PGDLLIMPORT int	PreAuthDelay

PGDLLIMPORT int	AuthenticationTimeout

PGDLLIMPORT bool	log_hostname

PGDLLIMPORT bool	enable_bonjour

PGDLLIMPORT char *	bonjour_name

PGDLLIMPORT bool	restart_after_crash

PGDLLIMPORT bool	remove_temp_files_after_crash

PGDLLIMPORT bool	send_abort_for_crash

PGDLLIMPORT bool	send_abort_for_kill

PGDLLIMPORT int	postmaster_alive_fds [2]

PGDLLIMPORT const char *	progname

PGDLLIMPORT bool	redirection_done

PGDLLIMPORT bool	LoadedSSL

PGDLLIMPORT struct ClientSocket *	MyClientSocket

PGDLLIMPORT dlist_head	ActiveChildList

Macro Definition Documentation

◆ POSTMASTER_FD_OWN

#define POSTMASTER_FD_OWN 1 /* kept open by postmaster only */

Definition at line 84 of file postmaster.h.

◆ POSTMASTER_FD_WATCH

#define POSTMASTER_FD_WATCH

Value:

0 /* used in children to check for

* postmaster death */

Definition at line 83 of file postmaster.h.

Typedef Documentation

◆ DispatchOption

typedef enum DispatchOption DispatchOption

Enumeration Type Documentation

◆ DispatchOption

enum DispatchOption

Enumerator
DISPATCH_CHECK
DISPATCH_BOOT
DISPATCH_FORKCHILD
DISPATCH_DESCRIBE_CONFIG
DISPATCH_SINGLE
DISPATCH_POSTMASTER

Definition at line 132 of file postmaster.h.

{
    DISPATCH_CHECK,
    DISPATCH_BOOT,
    DISPATCH_FORKCHILD,
    DISPATCH_DESCRIBE_CONFIG,
    DISPATCH_SINGLE,
    DISPATCH_POSTMASTER,        /* must be last */

Function Documentation

◆ AllocDeadEndChild()

PMChild * AllocDeadEndChild ( void )

Definition at line 224 of file pmchild.c.

{
    PMChild    *pmchild;
 
    elog(DEBUG2, "allocating dead-end child");
 
    pmchild = (PMChild *) palloc_extended(sizeof(PMChild), MCXT_ALLOC_NO_OOM);
    if (pmchild)
    {
        pmchild->pid = 0;
        pmchild->child_slot = 0;
        pmchild->bkend_type = B_DEAD_END_BACKEND;
        pmchild->rw = NULL;
        pmchild->bgworker_notify = false;
 
        dlist_push_head(&ActiveChildList, &pmchild->elem);
    }
 
    return pmchild;
}

References ActiveChildList, B_DEAD_END_BACKEND, PMChild::bgworker_notify, PMChild::bkend_type, PMChild::child_slot, DEBUG2, dlist_push_head(), PMChild::elem, elog, MCXT_ALLOC_NO_OOM, palloc_extended(), PMChild::pid, and PMChild::rw.

Referenced by BackendStartup().

◆ AssignPostmasterChildSlot()

PMChild * AssignPostmasterChildSlot ( BackendType btype )

Definition at line 178 of file pmchild.c.

{
    dlist_head *freelist;
    PMChild    *pmchild;
 
    if (pmchild_pools[btype].size == 0)
        elog(ERROR, "cannot allocate a PMChild slot for backend type %d", btype);
 
    freelist = &pmchild_pools[btype].freelist;
    if (dlist_is_empty(freelist))
        return NULL;
 
    pmchild = dlist_container(PMChild, elem, dlist_pop_head_node(freelist));
    pmchild->pid = 0;
    pmchild->bkend_type = btype;
    pmchild->rw = NULL;
    pmchild->bgworker_notify = true;
 
    /*
     * pmchild->child_slot for each entry was initialized when the array of
     * slots was allocated.  Sanity check it.
     */
    if (!(pmchild->child_slot >= pmchild_pools[btype].first_slotno &&
          pmchild->child_slot < pmchild_pools[btype].first_slotno + pmchild_pools[btype].size))
    {
        elog(ERROR, "pmchild freelist for backend type %d is corrupt",
             pmchild->bkend_type);
    }
 
    dlist_push_head(&ActiveChildList, &pmchild->elem);
 
    /* Update the status in the shared memory array */
    MarkPostmasterChildSlotAssigned(pmchild->child_slot);
 
    elog(DEBUG2, "assigned pm child slot %d for %s",
         pmchild->child_slot, PostmasterChildName(btype));
 
    return pmchild;
}

References ActiveChildList, PMChild::bgworker_notify, PMChild::bkend_type, PMChild::child_slot, DEBUG2, dlist_container, dlist_is_empty(), dlist_pop_head_node(), dlist_push_head(), PMChild::elem, elog, ERROR, PMChildPool::first_slotno, PMChildPool::freelist, MarkPostmasterChildSlotAssigned(), PMChild::pid, pmchild_pools, PostmasterChildName(), PMChild::rw, and PMChildPool::size.

Referenced by BackendStartup(), StartBackgroundWorker(), StartChildProcess(), and StartSysLogger().

◆ ClosePostmasterPorts()

void ClosePostmasterPorts ( bool am_syslogger )

Definition at line 1866 of file postmaster.c.

{
    /* Release resources held by the postmaster's WaitEventSet. */
    if (pm_wait_set)
    {
        FreeWaitEventSetAfterFork(pm_wait_set);
        pm_wait_set = NULL;
    }
 
#ifndef WIN32
 
    /*
     * Close the write end of postmaster death watch pipe. It's important to
     * do this as early as possible, so that if postmaster dies, others won't
     * think that it's still running because we're holding the pipe open.
     */
    if (close(postmaster_alive_fds[POSTMASTER_FD_OWN]) != 0)
        ereport(FATAL,
                (errcode_for_file_access(),
                 errmsg_internal("could not close postmaster death monitoring pipe in child process: %m")));
    postmaster_alive_fds[POSTMASTER_FD_OWN] = -1;
    /* Notify fd.c that we released one pipe FD. */
    ReleaseExternalFD();
#endif
 
    /*
     * Close the postmaster's listen sockets.  These aren't tracked by fd.c,
     * so we don't call ReleaseExternalFD() here.
     *
     * The listen sockets are marked as FD_CLOEXEC, so this isn't needed in
     * EXEC_BACKEND mode.
     */
#ifndef EXEC_BACKEND
    if (ListenSockets)
    {
        for (int i = 0; i < NumListenSockets; i++)
        {
            if (closesocket(ListenSockets[i]) != 0)
                elog(LOG, "could not close listen socket: %m");
        }
        pfree(ListenSockets);
    }
    NumListenSockets = 0;
    ListenSockets = NULL;
#endif
 
    /*
     * If using syslogger, close the read side of the pipe.  We don't bother
     * tracking this in fd.c, either.
     */
    if (!am_syslogger)
    {
#ifndef WIN32
        if (syslogPipe[0] >= 0)
            close(syslogPipe[0]);
        syslogPipe[0] = -1;
#else
        if (syslogPipe[0])
            CloseHandle(syslogPipe[0]);
        syslogPipe[0] = 0;
#endif
    }
 
#ifdef USE_BONJOUR
    /* If using Bonjour, close the connection to the mDNS daemon */
    if (bonjour_sdref)
        close(DNSServiceRefSockFD(bonjour_sdref));
#endif
}

References close, closesocket, elog, ereport, errcode_for_file_access(), errmsg_internal(), FATAL, FreeWaitEventSetAfterFork(), i, ListenSockets, LOG, NumListenSockets, pfree(), pm_wait_set, postmaster_alive_fds, POSTMASTER_FD_OWN, ReleaseExternalFD(), and syslogPipe.

Referenced by postmaster_child_launch().

◆ FindPostmasterChildByPid()

PMChild * FindPostmasterChildByPid ( int pid )

Definition at line 290 of file pmchild.c.

{
    dlist_iter  iter;
 
    dlist_foreach(iter, &ActiveChildList)
    {
        PMChild    *bp = dlist_container(PMChild, elem, iter.cur);
 
        if (bp->pid == pid)
            return bp;
    }
    return NULL;
}

References ActiveChildList, dlist_iter::cur, dlist_container, dlist_foreach, and PMChild::pid.

Referenced by process_pm_child_exit().

◆ InitPostmasterChildSlots()

void InitPostmasterChildSlots ( void )

Definition at line 97 of file pmchild.c.

{
    int         slotno;
    PMChild    *slots;
 
    /*
     * We allow more connections here than we can have backends because some
     * might still be authenticating; they might fail auth, or some existing
     * backend might exit before the auth cycle is completed.  The exact
     * MaxConnections limit is enforced when a new backend tries to join the
     * PGPROC array.
     *
     * WAL senders start out as regular backends, so they share the same pool.
     */
    pmchild_pools[B_BACKEND].size = 2 * (MaxConnections + max_wal_senders);
 
    pmchild_pools[B_AUTOVAC_WORKER].size = autovacuum_worker_slots;
    pmchild_pools[B_BG_WORKER].size = max_worker_processes;
    pmchild_pools[B_IO_WORKER].size = MAX_IO_WORKERS;
 
    /*
     * There can be only one of each of these running at a time.  They each
     * get their own pool of just one entry.
     */
    pmchild_pools[B_AUTOVAC_LAUNCHER].size = 1;
    pmchild_pools[B_SLOTSYNC_WORKER].size = 1;
    pmchild_pools[B_ARCHIVER].size = 1;
    pmchild_pools[B_BG_WRITER].size = 1;
    pmchild_pools[B_CHECKPOINTER].size = 1;
    pmchild_pools[B_STARTUP].size = 1;
    pmchild_pools[B_WAL_RECEIVER].size = 1;
    pmchild_pools[B_WAL_SUMMARIZER].size = 1;
    pmchild_pools[B_WAL_WRITER].size = 1;
    pmchild_pools[B_LOGGER].size = 1;
 
    /* The rest of the pmchild_pools are left at zero size */
 
    /* Count the total number of slots */
    num_pmchild_slots = 0;
    for (int i = 0; i < BACKEND_NUM_TYPES; i++)
        num_pmchild_slots += pmchild_pools[i].size;
 
    /* Allocate enough slots, and make sure Valgrind doesn't complain */
    slots = palloc(num_pmchild_slots * sizeof(PMChild));
#ifdef USE_VALGRIND
    pmchild_array = slots;
#endif
 
    /* Initialize them */
    slotno = 0;
    for (int btype = 0; btype < BACKEND_NUM_TYPES; btype++)
    {
        pmchild_pools[btype].first_slotno = slotno + 1;
        dlist_init(&pmchild_pools[btype].freelist);
 
        for (int j = 0; j < pmchild_pools[btype].size; j++)
        {
            slots[slotno].pid = 0;
            slots[slotno].child_slot = slotno + 1;
            slots[slotno].bkend_type = B_INVALID;
            slots[slotno].rw = NULL;
            slots[slotno].bgworker_notify = false;
            dlist_push_tail(&pmchild_pools[btype].freelist, &slots[slotno].elem);
            slotno++;
        }
    }
    Assert(slotno == num_pmchild_slots);
 
    /* Initialize other structures */
    dlist_init(&ActiveChildList);
}

References ActiveChildList, Assert(), autovacuum_worker_slots, B_ARCHIVER, B_AUTOVAC_LAUNCHER, B_AUTOVAC_WORKER, B_BACKEND, B_BG_WORKER, B_BG_WRITER, B_CHECKPOINTER, B_INVALID, B_IO_WORKER, B_LOGGER, B_SLOTSYNC_WORKER, B_STARTUP, B_WAL_RECEIVER, B_WAL_SUMMARIZER, B_WAL_WRITER, BACKEND_NUM_TYPES, PMChild::bgworker_notify, PMChild::bkend_type, PMChild::child_slot, dlist_init(), dlist_push_tail(), PMChildPool::first_slotno, i, j, MAX_IO_WORKERS, max_wal_senders, max_worker_processes, MaxConnections, num_pmchild_slots, palloc(), PMChild::pid, pmchild_pools, PMChild::rw, and PMChildPool::size.

Referenced by BootstrapModeMain(), PostgresSingleUserMain(), and PostmasterMain().

◆ InitProcessGlobals()

void InitProcessGlobals ( void )

Definition at line 1943 of file postmaster.c.

{
    MyStartTimestamp = GetCurrentTimestamp();
    MyStartTime = timestamptz_to_time_t(MyStartTimestamp);
 
    /*
     * Set a different global seed in every process.  We want something
     * unpredictable, so if possible, use high-quality random bits for the
     * seed.  Otherwise, fall back to a seed based on timestamp and PID.
     */
    if (unlikely(!pg_prng_strong_seed(&pg_global_prng_state)))
    {
        uint64      rseed;
 
        /*
         * Since PIDs and timestamps tend to change more frequently in their
         * least significant bits, shift the timestamp left to allow a larger
         * total number of seeds in a given time period.  Since that would
         * leave only 20 bits of the timestamp that cycle every ~1 second,
         * also mix in some higher bits.
         */
        rseed = ((uint64) MyProcPid) ^
            ((uint64) MyStartTimestamp << 12) ^
            ((uint64) MyStartTimestamp >> 20);
 
        pg_prng_seed(&pg_global_prng_state, rseed);
    }
 
    /*
     * Also make sure that we've set a good seed for random(3).  Use of that
     * is deprecated in core Postgres, but extensions might use it.
     */
#ifndef WIN32
    srandom(pg_prng_uint32(&pg_global_prng_state));
#endif
}

References GetCurrentTimestamp(), MyProcPid, MyStartTime, MyStartTimestamp, pg_global_prng_state, pg_prng_seed(), pg_prng_strong_seed, pg_prng_uint32(), timestamptz_to_time_t(), and unlikely.

Referenced by InitPostmasterChild(), InitStandaloneProcess(), and PostmasterMain().

◆ MaxLivePostmasterChildren()

int MaxLivePostmasterChildren ( void )

Definition at line 81 of file pmchild.c.

{
    if (num_pmchild_slots == 0)
        elog(ERROR, "PM child array not initialized yet");
    return num_pmchild_slots;
}

References elog, ERROR, and num_pmchild_slots.

Referenced by PMSignalShmemInit(), and PMSignalShmemSize().

◆ parse_dispatch_option()

DispatchOption parse_dispatch_option ( const char * name )

Definition at line 244 of file main.c.

{
    for (int i = 0; i < lengthof(DispatchOptionNames); i++)
    {
        /*
         * Unlike the other dispatch options, "forkchild" takes an argument,
         * so we just look for the prefix for that one.  For non-EXEC_BACKEND
         * builds, we never want to return DISPATCH_FORKCHILD, so skip over it
         * in that case.
         */
        if (i == DISPATCH_FORKCHILD)
        {
#ifdef EXEC_BACKEND
            if (strncmp(DispatchOptionNames[DISPATCH_FORKCHILD], name,
                        strlen(DispatchOptionNames[DISPATCH_FORKCHILD])) == 0)
                return DISPATCH_FORKCHILD;
#endif
            continue;
        }
 
        if (strcmp(DispatchOptionNames[i], name) == 0)
            return (DispatchOption) i;
    }
 
    /* no match means this is a postmaster */
    return DISPATCH_POSTMASTER;
}

References DISPATCH_FORKCHILD, DISPATCH_POSTMASTER, DispatchOptionNames, i, lengthof, and name.

Referenced by BootstrapModeMain(), main(), PostmasterMain(), and process_postgres_switches().

◆ postmaster_child_launch()

pid_t postmaster_child_launch	(	BackendType	child_type,
		int	child_slot,
		void *	startup_data,
		size_t	startup_data_len,
		struct ClientSocket *	client_sock
	)

Definition at line 207 of file launch_backend.c.

{
    pid_t       pid;
 
    Assert(IsPostmasterEnvironment && !IsUnderPostmaster);
 
    /* Capture time Postmaster initiates process creation for logging */
    if (IsExternalConnectionBackend(child_type))
        ((BackendStartupData *) startup_data)->fork_started = GetCurrentTimestamp();
 
#ifdef EXEC_BACKEND
    pid = internal_forkexec(child_process_kinds[child_type].name, child_slot,
                            startup_data, startup_data_len, client_sock);
    /* the child process will arrive in SubPostmasterMain */
#else                           /* !EXEC_BACKEND */
    pid = fork_process();
    if (pid == 0)               /* child */
    {
        /* Capture and transfer timings that may be needed for logging */
        if (IsExternalConnectionBackend(child_type))
        {
            conn_timing.socket_create =
                ((BackendStartupData *) startup_data)->socket_created;
            conn_timing.fork_start =
                ((BackendStartupData *) startup_data)->fork_started;
            conn_timing.fork_end = GetCurrentTimestamp();
        }
 
        /* Close the postmaster's sockets */
        ClosePostmasterPorts(child_type == B_LOGGER);
 
        /* Detangle from postmaster */
        InitPostmasterChild();
 
        /* Detach shared memory if not needed. */
        if (!child_process_kinds[child_type].shmem_attach)
        {
            dsm_detach_all();
            PGSharedMemoryDetach();
        }
 
        /*
         * Enter the Main function with TopMemoryContext.  The startup data is
         * allocated in PostmasterContext, so we cannot release it here yet.
         * The Main function will do it after it's done handling the startup
         * data.
         */
        MemoryContextSwitchTo(TopMemoryContext);
 
        MyPMChildSlot = child_slot;
        if (client_sock)
        {
            MyClientSocket = palloc(sizeof(ClientSocket));
            memcpy(MyClientSocket, client_sock, sizeof(ClientSocket));
        }
 
        /*
         * Run the appropriate Main function
         */
        child_process_kinds[child_type].main_fn(startup_data, startup_data_len);
        pg_unreachable();       /* main_fn never returns */
    }
#endif                          /* EXEC_BACKEND */
    return pid;
}

References Assert(), B_LOGGER, child_process_kinds, ClosePostmasterPorts(), conn_timing, dsm_detach_all(), ConnectionTiming::fork_end, fork_process(), ConnectionTiming::fork_start, GetCurrentTimestamp(), InitPostmasterChild(), IsExternalConnectionBackend, IsPostmasterEnvironment, IsUnderPostmaster, child_process_kind::main_fn, MemoryContextSwitchTo(), MyClientSocket, MyPMChildSlot, name, palloc(), pg_unreachable, PGSharedMemoryDetach(), ConnectionTiming::socket_create, and TopMemoryContext.

Referenced by BackendStartup(), StartBackgroundWorker(), StartChildProcess(), and SysLogger_Start().

◆ PostmasterChildName()

const char * PostmasterChildName ( BackendType child_type )

Definition at line 189 of file launch_backend.c.

{
    return child_process_kinds[child_type].name;
}

References child_process_kinds, and child_process_kind::name.

Referenced by AssignPostmasterChildSlot(), and StartChildProcess().

◆ PostmasterMain()

pg_noreturn void PostmasterMain	(	int	argc,
		char *	argv[]
	)

Definition at line 493 of file postmaster.c.

{
    int         opt;
    int         status;
    char       *userDoption = NULL;
    bool        listen_addr_saved = false;
    char       *output_config_variable = NULL;
 
    InitProcessGlobals();
 
    PostmasterPid = MyProcPid;
 
    IsPostmasterEnvironment = true;
 
    /*
     * Start our win32 signal implementation
     */
#ifdef WIN32
    pgwin32_signal_initialize();
#endif
 
    /*
     * We should not be creating any files or directories before we check the
     * data directory (see checkDataDir()), but just in case set the umask to
     * the most restrictive (owner-only) permissions.
     *
     * checkDataDir() will reset the umask based on the data directory
     * permissions.
     */
    umask(PG_MODE_MASK_OWNER);
 
    /*
     * By default, palloc() requests in the postmaster will be allocated in
     * the PostmasterContext, which is space that can be recycled by backends.
     * Allocated data that needs to be available to backends should be
     * allocated in TopMemoryContext.
     */
    PostmasterContext = AllocSetContextCreate(TopMemoryContext,
                                              "Postmaster",
                                              ALLOCSET_DEFAULT_SIZES);
    MemoryContextSwitchTo(PostmasterContext);
 
    /* Initialize paths to installation files */
    getInstallationPaths(argv[0]);
 
    /*
     * Set up signal handlers for the postmaster process.
     *
     * CAUTION: when changing this list, check for side-effects on the signal
     * handling setup of child processes.  See tcop/postgres.c,
     * bootstrap/bootstrap.c, postmaster/bgwriter.c, postmaster/walwriter.c,
     * postmaster/autovacuum.c, postmaster/pgarch.c, postmaster/syslogger.c,
     * postmaster/bgworker.c and postmaster/checkpointer.c.
     */
    pqinitmask();
    sigprocmask(SIG_SETMASK, &BlockSig, NULL);
 
    pqsignal(SIGHUP, handle_pm_reload_request_signal);
    pqsignal(SIGINT, handle_pm_shutdown_request_signal);
    pqsignal(SIGQUIT, handle_pm_shutdown_request_signal);
    pqsignal(SIGTERM, handle_pm_shutdown_request_signal);
    pqsignal(SIGALRM, SIG_IGN); /* ignored */
    pqsignal(SIGPIPE, SIG_IGN); /* ignored */
    pqsignal(SIGUSR1, handle_pm_pmsignal_signal);
    pqsignal(SIGUSR2, dummy_handler);   /* unused, reserve for children */
    pqsignal(SIGCHLD, handle_pm_child_exit_signal);
 
    /* This may configure SIGURG, depending on platform. */
    InitializeWaitEventSupport();
    InitProcessLocalLatch();
 
    /*
     * No other place in Postgres should touch SIGTTIN/SIGTTOU handling.  We
     * ignore those signals in a postmaster environment, so that there is no
     * risk of a child process freezing up due to writing to stderr.  But for
     * a standalone backend, their default handling is reasonable.  Hence, all
     * child processes should just allow the inherited settings to stand.
     */
#ifdef SIGTTIN
    pqsignal(SIGTTIN, SIG_IGN); /* ignored */
#endif
#ifdef SIGTTOU
    pqsignal(SIGTTOU, SIG_IGN); /* ignored */
#endif
 
    /* ignore SIGXFSZ, so that ulimit violations work like disk full */
#ifdef SIGXFSZ
    pqsignal(SIGXFSZ, SIG_IGN); /* ignored */
#endif
 
    /* Begin accepting signals. */
    sigprocmask(SIG_SETMASK, &UnBlockSig, NULL);
 
    /*
     * Options setup
     */
    InitializeGUCOptions();
 
    opterr = 1;
 
    /*
     * Parse command-line options.  CAUTION: keep this in sync with
     * tcop/postgres.c (the option sets should not conflict) and with the
     * common help() function in main/main.c.
     */
    while ((opt = getopt(argc, argv, "B:bC:c:D:d:EeFf:h:ijk:lN:OPp:r:S:sTt:W:-:")) != -1)
    {
        switch (opt)
        {
            case 'B':
                SetConfigOption("shared_buffers", optarg, PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'b':
                /* Undocumented flag used for binary upgrades */
                IsBinaryUpgrade = true;
                break;
 
            case 'C':
                output_config_variable = strdup(optarg);
                break;
 
            case '-':
 
                /*
                 * Error if the user misplaced a special must-be-first option
                 * for dispatching to a subprogram.  parse_dispatch_option()
                 * returns DISPATCH_POSTMASTER if it doesn't find a match, so
                 * error for anything else.
                 */
                if (parse_dispatch_option(optarg) != DISPATCH_POSTMASTER)
                    ereport(ERROR,
                            (errcode(ERRCODE_SYNTAX_ERROR),
                             errmsg("--%s must be first argument", optarg)));
 
                /* FALLTHROUGH */
            case 'c':
                {
                    char       *name,
                               *value;
 
                    ParseLongOption(optarg, &name, &value);
                    if (!value)
                    {
                        if (opt == '-')
                            ereport(ERROR,
                                    (errcode(ERRCODE_SYNTAX_ERROR),
                                     errmsg("--%s requires a value",
                                            optarg)));
                        else
                            ereport(ERROR,
                                    (errcode(ERRCODE_SYNTAX_ERROR),
                                     errmsg("-c %s requires a value",
                                            optarg)));
                    }
 
                    SetConfigOption(name, value, PGC_POSTMASTER, PGC_S_ARGV);
                    pfree(name);
                    pfree(value);
                    break;
                }
 
            case 'D':
                userDoption = strdup(optarg);
                break;
 
            case 'd':
                set_debug_options(atoi(optarg), PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'E':
                SetConfigOption("log_statement", "all", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'e':
                SetConfigOption("datestyle", "euro", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'F':
                SetConfigOption("fsync", "false", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'f':
                if (!set_plan_disabling_options(optarg, PGC_POSTMASTER, PGC_S_ARGV))
                {
                    write_stderr("%s: invalid argument for option -f: \"%s\"\n",
                                 progname, optarg);
                    ExitPostmaster(1);
                }
                break;
 
            case 'h':
                SetConfigOption("listen_addresses", optarg, PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'i':
                SetConfigOption("listen_addresses", "*", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'j':
                /* only used by interactive backend */
                break;
 
            case 'k':
                SetConfigOption("unix_socket_directories", optarg, PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'l':
                SetConfigOption("ssl", "true", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'N':
                SetConfigOption("max_connections", optarg, PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'O':
                SetConfigOption("allow_system_table_mods", "true", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'P':
                SetConfigOption("ignore_system_indexes", "true", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'p':
                SetConfigOption("port", optarg, PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'r':
                /* only used by single-user backend */
                break;
 
            case 'S':
                SetConfigOption("work_mem", optarg, PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 's':
                SetConfigOption("log_statement_stats", "true", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 'T':
 
                /*
                 * This option used to be defined as sending SIGSTOP after a
                 * backend crash, but sending SIGABRT seems more useful.
                 */
                SetConfigOption("send_abort_for_crash", "true", PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            case 't':
                {
                    const char *tmp = get_stats_option_name(optarg);
 
                    if (tmp)
                    {
                        SetConfigOption(tmp, "true", PGC_POSTMASTER, PGC_S_ARGV);
                    }
                    else
                    {
                        write_stderr("%s: invalid argument for option -t: \"%s\"\n",
                                     progname, optarg);
                        ExitPostmaster(1);
                    }
                    break;
                }
 
            case 'W':
                SetConfigOption("post_auth_delay", optarg, PGC_POSTMASTER, PGC_S_ARGV);
                break;
 
            default:
                write_stderr("Try \"%s --help\" for more information.\n",
                             progname);
                ExitPostmaster(1);
        }
    }
 
    /*
     * Postmaster accepts no non-option switch arguments.
     */
    if (optind < argc)
    {
        write_stderr("%s: invalid argument: \"%s\"\n",
                     progname, argv[optind]);
        write_stderr("Try \"%s --help\" for more information.\n",
                     progname);
        ExitPostmaster(1);
    }
 
    /*
     * Locate the proper configuration files and data directory, and read
     * postgresql.conf for the first time.
     */
    if (!SelectConfigFiles(userDoption, progname))
        ExitPostmaster(2);
 
    if (output_config_variable != NULL)
    {
        /*
         * If this is a runtime-computed GUC, it hasn't yet been initialized,
         * and the present value is not useful.  However, this is a convenient
         * place to print the value for most GUCs because it is safe to run
         * postmaster startup to this point even if the server is already
         * running.  For the handful of runtime-computed GUCs that we cannot
         * provide meaningful values for yet, we wait until later in
         * postmaster startup to print the value.  We won't be able to use -C
         * on running servers for those GUCs, but using this option now would
         * lead to incorrect results for them.
         */
        int         flags = GetConfigOptionFlags(output_config_variable, true);
 
        if ((flags & GUC_RUNTIME_COMPUTED) == 0)
        {
            /*
             * "-C guc" was specified, so print GUC's value and exit.  No
             * extra permission check is needed because the user is reading
             * inside the data dir.
             */
            const char *config_val = GetConfigOption(output_config_variable,
                                                     false, false);
 
            puts(config_val ? config_val : "");
            ExitPostmaster(0);
        }
 
        /*
         * A runtime-computed GUC will be printed later on.  As we initialize
         * a server startup sequence, silence any log messages that may show
         * up in the output generated.  FATAL and more severe messages are
         * useful to show, even if one would only expect at least PANIC.  LOG
         * entries are hidden.
         */
        SetConfigOption("log_min_messages", "FATAL", PGC_SUSET,
                        PGC_S_OVERRIDE);
    }
 
    /* Verify that DataDir looks reasonable */
    checkDataDir();
 
    /* Check that pg_control exists */
    checkControlFile();
 
    /* And switch working directory into it */
    ChangeToDataDir();
 
    /*
     * Check for invalid combinations of GUC settings.
     */
    if (SuperuserReservedConnections + ReservedConnections >= MaxConnections)
    {
        write_stderr("%s: \"superuser_reserved_connections\" (%d) plus \"reserved_connections\" (%d) must be less than \"max_connections\" (%d)\n",
                     progname,
                     SuperuserReservedConnections, ReservedConnections,
                     MaxConnections);
        ExitPostmaster(1);
    }
    if (XLogArchiveMode > ARCHIVE_MODE_OFF && wal_level == WAL_LEVEL_MINIMAL)
        ereport(ERROR,
                (errmsg("WAL archival cannot be enabled when \"wal_level\" is \"minimal\"")));
    if (max_wal_senders > 0 && wal_level == WAL_LEVEL_MINIMAL)
        ereport(ERROR,
                (errmsg("WAL streaming (\"max_wal_senders\" > 0) requires \"wal_level\" to be \"replica\" or \"logical\"")));
    if (summarize_wal && wal_level == WAL_LEVEL_MINIMAL)
        ereport(ERROR,
                (errmsg("WAL cannot be summarized when \"wal_level\" is \"minimal\"")));
    if (sync_replication_slots && wal_level < WAL_LEVEL_LOGICAL)
        ereport(ERROR,
                (errmsg("replication slot synchronization (\"sync_replication_slots\" = on) requires \"wal_level\" >= \"logical\"")));
 
    /*
     * Other one-time internal sanity checks can go here, if they are fast.
     * (Put any slow processing further down, after postmaster.pid creation.)
     */
    if (!CheckDateTokenTables())
    {
        write_stderr("%s: invalid datetoken tables, please fix\n", progname);
        ExitPostmaster(1);
    }
 
    /*
     * Now that we are done processing the postmaster arguments, reset
     * getopt(3) library so that it will work correctly in subprocesses.
     */
    optind = 1;
#ifdef HAVE_INT_OPTRESET
    optreset = 1;               /* some systems need this too */
#endif
 
    /* For debugging: display postmaster environment */
    if (message_level_is_interesting(DEBUG3))
    {
#if !defined(WIN32)
        extern char **environ;
#endif
        char      **p;
        StringInfoData si;
 
        initStringInfo(&si);
 
        appendStringInfoString(&si, "initial environment dump:");
        for (p = environ; *p; ++p)
            appendStringInfo(&si, "\n%s", *p);
 
        ereport(DEBUG3, errmsg_internal("%s", si.data));
        pfree(si.data);
    }
 
    /*
     * 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(s).
     *
     * Also note that this internally sets up the on_proc_exit function that
     * is responsible for removing both data directory and socket lockfiles;
     * so it must happen before opening sockets so that at exit, the socket
     * lockfiles go away after CloseServerPorts runs.
     */
    CreateDataDirLockFile(true);
 
    /*
     * Read the control file (for error checking and config info).
     *
     * Since we verify the control file's CRC, this has a useful side effect
     * on machines where we need a run-time test for CRC support instructions.
     * The postmaster will do the test once at startup, and then its child
     * processes will inherit the correct function pointer and not need to
     * repeat the test.
     */
    LocalProcessControlFile(false);
 
    /*
     * Register the apply launcher.  It's probably a good idea to call this
     * before any modules had a chance to take the background worker slots.
     */
    ApplyLauncherRegister();
 
    /*
     * process any libraries that should be preloaded at postmaster start
     */
    process_shared_preload_libraries();
 
    /*
     * Initialize SSL library, if specified.
     */
#ifdef USE_SSL
    if (EnableSSL)
    {
        (void) secure_initialize(true);
        LoadedSSL = true;
    }
#endif
 
    /*
     * Now that loadable modules have had their chance to alter any GUCs,
     * calculate MaxBackends and initialize the machinery to track child
     * processes.
     */
    InitializeMaxBackends();
    InitPostmasterChildSlots();
 
    /*
     * Calculate the size of the PGPROC fast-path lock arrays.
     */
    InitializeFastPathLocks();
 
    /*
     * Give preloaded libraries a chance to request additional shared memory.
     */
    process_shmem_requests();
 
    /*
     * Now that loadable modules have had their chance to request additional
     * shared memory, determine the value of any runtime-computed GUCs that
     * depend on the amount of shared memory required.
     */
    InitializeShmemGUCs();
 
    /*
     * Now that modules have been loaded, we can process any custom resource
     * managers specified in the wal_consistency_checking GUC.
     */
    InitializeWalConsistencyChecking();
 
    /*
     * If -C was specified with a runtime-computed GUC, we held off printing
     * the value earlier, as the GUC was not yet initialized.  We handle -C
     * for most GUCs before we lock the data directory so that the option may
     * be used on a running server.  However, a handful of GUCs are runtime-
     * computed and do not have meaningful values until after locking the data
     * directory, and we cannot safely calculate their values earlier on a
     * running server.  At this point, such GUCs should be properly
     * initialized, and we haven't yet set up shared memory, so this is a good
     * time to handle the -C option for these special GUCs.
     */
    if (output_config_variable != NULL)
    {
        const char *config_val = GetConfigOption(output_config_variable,
                                                 false, false);
 
        puts(config_val ? config_val : "");
        ExitPostmaster(0);
    }
 
    /*
     * Set up shared memory and semaphores.
     *
     * Note: if using SysV shmem and/or semas, each postmaster startup will
     * normally choose the same IPC keys.  This helps ensure that we will
     * clean up dead IPC objects if the postmaster crashes and is restarted.
     */
    CreateSharedMemoryAndSemaphores();
 
    /*
     * 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 pipe (or process handle on Windows) that allows children to
     * wake up from sleep on postmaster death.
     */
    InitPostmasterDeathWatchHandle();
 
#ifdef WIN32
 
    /*
     * Initialize I/O completion port used to deliver list of dead children.
     */
    win32ChildQueue = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 1);
    if (win32ChildQueue == NULL)
        ereport(FATAL,
                (errmsg("could not create I/O completion port for child queue")));
#endif
 
#ifdef EXEC_BACKEND
    /* Write out nondefault GUC settings for child processes to use */
    write_nondefault_variables(PGC_POSTMASTER);
 
    /*
     * Clean out the temp directory used to transmit parameters to child
     * processes (see internal_forkexec).  We must do this before launching
     * any child processes, else we have a race condition: we could remove a
     * parameter file before the child can read it.  It should be safe to do
     * so now, because we verified earlier that there are no conflicting
     * Postgres processes in this data directory.
     */
    RemovePgTempFilesInDir(PG_TEMP_FILES_DIR, true, false);
#endif
 
    /*
     * Forcibly remove the files signaling a standby promotion request.
     * Otherwise, the existence of those files triggers a promotion too early,
     * whether a user wants that or not.
     *
     * This removal of files is usually unnecessary because they can exist
     * only during a few moments during a standby promotion. However there is
     * a race condition: if pg_ctl promote is executed and creates the files
     * during a promotion, the files can stay around even after the server is
     * brought up to be the primary.  Then, if a new standby starts by using
     * the backup taken from the new primary, the files can exist at server
     * startup and must be removed in order to avoid an unexpected promotion.
     *
     * Note that promotion signal files need to be removed before the startup
     * process is invoked. Because, after that, they can be used by
     * postmaster's SIGUSR1 signal handler.
     */
    RemovePromoteSignalFiles();
 
    /* Do the same for logrotate signal file */
    RemoveLogrotateSignalFiles();
 
    /* Remove any outdated file holding the current log filenames. */
    if (unlink(LOG_METAINFO_DATAFILE) < 0 && errno != ENOENT)
        ereport(LOG,
                (errcode_for_file_access(),
                 errmsg("could not remove file \"%s\": %m",
                        LOG_METAINFO_DATAFILE)));
 
    /*
     * If enabled, start up syslogger collection subprocess
     */
    if (Logging_collector)
        StartSysLogger();
 
    /*
     * Reset whereToSendOutput from DestDebug (its starting state) to
     * DestNone. This stops ereport from sending log messages to stderr unless
     * Log_destination permits.  We don't do this until the postmaster is
     * fully launched, since startup failures may as well be reported to
     * stderr.
     *
     * If we are in fact disabling logging to stderr, first emit a log message
     * saying so, to provide a breadcrumb trail for users who may not remember
     * that their logging is configured to go somewhere else.
     */
    if (!(Log_destination & LOG_DESTINATION_STDERR))
        ereport(LOG,
                (errmsg("ending log output to stderr"),
                 errhint("Future log output will go to log destination \"%s\".",
                         Log_destination_string)));
 
    whereToSendOutput = DestNone;
 
    /*
     * Report server startup in log.  While we could emit this much earlier,
     * it seems best to do so after starting the log collector, if we intend
     * to use one.
     */
    ereport(LOG,
            (errmsg("starting %s", PG_VERSION_STR)));
 
    /*
     * Establish input sockets.
     *
     * First set up an on_proc_exit function that's charged with closing the
     * sockets again at postmaster shutdown.
     */
    ListenSockets = palloc(MAXLISTEN * sizeof(pgsocket));
    on_proc_exit(CloseServerPorts, 0);
 
    if (ListenAddresses)
    {
        char       *rawstring;
        List       *elemlist;
        ListCell   *l;
        int         success = 0;
 
        /* Need a modifiable copy of ListenAddresses */
        rawstring = pstrdup(ListenAddresses);
 
        /* Parse string into list of hostnames */
        if (!SplitGUCList(rawstring, ',', &elemlist))
        {
            /* syntax error in list */
            ereport(FATAL,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("invalid list syntax in parameter \"%s\"",
                            "listen_addresses")));
        }
 
        foreach(l, elemlist)
        {
            char       *curhost = (char *) lfirst(l);
 
            if (strcmp(curhost, "*") == 0)
                status = ListenServerPort(AF_UNSPEC, NULL,
                                          (unsigned short) PostPortNumber,
                                          NULL,
                                          ListenSockets,
                                          &NumListenSockets,
                                          MAXLISTEN);
            else
                status = ListenServerPort(AF_UNSPEC, curhost,
                                          (unsigned short) PostPortNumber,
                                          NULL,
                                          ListenSockets,
                                          &NumListenSockets,
                                          MAXLISTEN);
 
            if (status == STATUS_OK)
            {
                success++;
                /* record the first successful host addr in lockfile */
                if (!listen_addr_saved)
                {
                    AddToDataDirLockFile(LOCK_FILE_LINE_LISTEN_ADDR, curhost);
                    listen_addr_saved = true;
                }
            }
            else
                ereport(WARNING,
                        (errmsg("could not create listen socket for \"%s\"",
                                curhost)));
        }
 
        if (!success && elemlist != NIL)
            ereport(FATAL,
                    (errmsg("could not create any TCP/IP sockets")));
 
        list_free(elemlist);
        pfree(rawstring);
    }
 
#ifdef USE_BONJOUR
    /* Register for Bonjour only if we opened TCP socket(s) */
    if (enable_bonjour && NumListenSockets > 0)
    {
        DNSServiceErrorType err;
 
        /*
         * We pass 0 for interface_index, which will result in registering on
         * all "applicable" interfaces.  It's not entirely clear from the
         * DNS-SD docs whether this would be appropriate if we have bound to
         * just a subset of the available network interfaces.
         */
        err = DNSServiceRegister(&bonjour_sdref,
                                 0,
                                 0,
                                 bonjour_name,
                                 "_postgresql._tcp.",
                                 NULL,
                                 NULL,
                                 pg_hton16(PostPortNumber),
                                 0,
                                 NULL,
                                 NULL,
                                 NULL);
        if (err != kDNSServiceErr_NoError)
            ereport(LOG,
                    (errmsg("DNSServiceRegister() failed: error code %ld",
                            (long) err)));
 
        /*
         * We don't bother to read the mDNS daemon's reply, and we expect that
         * it will automatically terminate our registration when the socket is
         * closed at postmaster termination.  So there's nothing more to be
         * done here.  However, the bonjour_sdref is kept around so that
         * forked children can close their copies of the socket.
         */
    }
#endif
 
    if (Unix_socket_directories)
    {
        char       *rawstring;
        List       *elemlist;
        ListCell   *l;
        int         success = 0;
 
        /* Need a modifiable copy of Unix_socket_directories */
        rawstring = pstrdup(Unix_socket_directories);
 
        /* Parse string into list of directories */
        if (!SplitDirectoriesString(rawstring, ',', &elemlist))
        {
            /* syntax error in list */
            ereport(FATAL,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("invalid list syntax in parameter \"%s\"",
                            "unix_socket_directories")));
        }
 
        foreach(l, elemlist)
        {
            char       *socketdir = (char *) lfirst(l);
 
            status = ListenServerPort(AF_UNIX, NULL,
                                      (unsigned short) PostPortNumber,
                                      socketdir,
                                      ListenSockets,
                                      &NumListenSockets,
                                      MAXLISTEN);
 
            if (status == STATUS_OK)
            {
                success++;
                /* record the first successful Unix socket in lockfile */
                if (success == 1)
                    AddToDataDirLockFile(LOCK_FILE_LINE_SOCKET_DIR, socketdir);
            }
            else
                ereport(WARNING,
                        (errmsg("could not create Unix-domain socket in directory \"%s\"",
                                socketdir)));
        }
 
        if (!success && elemlist != NIL)
            ereport(FATAL,
                    (errmsg("could not create any Unix-domain sockets")));
 
        list_free_deep(elemlist);
        pfree(rawstring);
    }
 
    /*
     * check that we have some socket to listen on
     */
    if (NumListenSockets == 0)
        ereport(FATAL,
                (errmsg("no socket created for listening")));
 
    /*
     * If no valid TCP ports, write an empty line for listen address,
     * indicating the Unix socket must be used.  Note that this line is not
     * added to the lock file until there is a socket backing it.
     */
    if (!listen_addr_saved)
        AddToDataDirLockFile(LOCK_FILE_LINE_LISTEN_ADDR, "");
 
    /*
     * Record postmaster options.  We delay this till now to avoid recording
     * bogus options (eg, unusable port number).
     */
    if (!CreateOptsFile(argc, argv, my_exec_path))
        ExitPostmaster(1);
 
    /*
     * Write the external PID file if requested
     */
    if (external_pid_file)
    {
        FILE       *fpidfile = fopen(external_pid_file, "w");
 
        if (fpidfile)
        {
            fprintf(fpidfile, "%d\n", MyProcPid);
            fclose(fpidfile);
 
            /* Make PID file world readable */
            if (chmod(external_pid_file, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) != 0)
                write_stderr("%s: could not change permissions of external PID file \"%s\": %m\n",
                             progname, external_pid_file);
        }
        else
            write_stderr("%s: could not write external PID file \"%s\": %m\n",
                         progname, external_pid_file);
 
        on_proc_exit(unlink_external_pid_file, 0);
    }
 
    /*
     * Remove old temporary files.  At this point there can be no other
     * Postgres processes running in this directory, so this should be safe.
     */
    RemovePgTempFiles();
 
    /*
     * Initialize the autovacuum subsystem (again, no process start yet)
     */
    autovac_init();
 
    /*
     * Load configuration files for client authentication.
     */
    if (!load_hba())
    {
        /*
         * It makes no sense to continue if we fail to load the HBA file,
         * since there is no way to connect to the database in this case.
         */
        ereport(FATAL,
        /* translator: %s is a configuration file */
                (errmsg("could not load %s", HbaFileName)));
    }
    if (!load_ident())
    {
        /*
         * We can start up without the IDENT file, although it means that you
         * cannot log in using any of the authentication methods that need a
         * user name mapping. load_ident() already logged the details of error
         * to the log.
         */
    }
 
#ifdef HAVE_PTHREAD_IS_THREADED_NP
 
    /*
     * On macOS, libintl replaces setlocale() with a version that calls
     * CFLocaleCopyCurrent() when its second argument is "" and every relevant
     * environment variable is unset or empty.  CFLocaleCopyCurrent() makes
     * the process multithreaded.  The postmaster calls sigprocmask() and
     * calls fork() without an immediate exec(), both of which have undefined
     * behavior in a multithreaded program.  A multithreaded postmaster is the
     * normal case on Windows, which offers neither fork() nor sigprocmask().
     * Currently, macOS is the only platform having pthread_is_threaded_np(),
     * so we need not worry whether this HINT is appropriate elsewhere.
     */
    if (pthread_is_threaded_np() != 0)
        ereport(FATAL,
                (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
                 errmsg("postmaster became multithreaded during startup"),
                 errhint("Set the LC_ALL environment variable to a valid locale.")));
#endif
 
    /*
     * Remember postmaster startup time
     */
    PgStartTime = GetCurrentTimestamp();
 
    /*
     * Report postmaster status in the postmaster.pid file, to allow pg_ctl to
     * see what's happening.
     */
    AddToDataDirLockFile(LOCK_FILE_LINE_PM_STATUS, PM_STATUS_STARTING);
 
    UpdatePMState(PM_STARTUP);
 
    /* Make sure we can perform I/O while starting up. */
    maybe_adjust_io_workers();
 
    /* Start bgwriter and checkpointer so they can help with recovery */
    if (CheckpointerPMChild == NULL)
        CheckpointerPMChild = StartChildProcess(B_CHECKPOINTER);
    if (BgWriterPMChild == NULL)
        BgWriterPMChild = StartChildProcess(B_BG_WRITER);
 
    /*
     * We're ready to rock and roll...
     */
    StartupPMChild = StartChildProcess(B_STARTUP);
    Assert(StartupPMChild != NULL);
    StartupStatus = STARTUP_RUNNING;
 
    /* Some workers may be scheduled to start now */
    maybe_start_bgworkers();
 
    status = ServerLoop();
 
    /*
     * ServerLoop probably shouldn't ever return, but if it does, close down.
     */
    ExitPostmaster(status != STATUS_OK);
 
    abort();                    /* not reached */
}

References AddToDataDirLockFile(), ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, appendStringInfo(), appendStringInfoString(), ApplyLauncherRegister(), ARCHIVE_MODE_OFF, Assert(), autovac_init(), B_BG_WRITER, B_CHECKPOINTER, B_STARTUP, BgWriterPMChild, BlockSig, bonjour_name, ChangeToDataDir(), checkControlFile(), checkDataDir(), CheckDateTokenTables(), CheckpointerPMChild, CloseServerPorts(), CreateDataDirLockFile(), CreateOptsFile(), CreateSharedMemoryAndSemaphores(), StringInfoData::data, DEBUG3, DestNone, DISPATCH_POSTMASTER, dummy_handler(), enable_bonjour, EnableSSL, environ, ereport, err(), errcode(), errcode_for_file_access(), errhint(), errmsg(), errmsg_internal(), ERROR, ExitPostmaster(), external_pid_file, FATAL, fprintf, get_stats_option_name(), GetConfigOption(), GetConfigOptionFlags(), GetCurrentTimestamp(), getInstallationPaths(), getopt(), GUC_RUNTIME_COMPUTED, handle_pm_child_exit_signal(), handle_pm_pmsignal_signal(), handle_pm_reload_request_signal(), handle_pm_shutdown_request_signal(), HbaFileName, InitializeFastPathLocks(), InitializeGUCOptions(), InitializeMaxBackends(), InitializeShmemGUCs(), InitializeWaitEventSupport(), InitializeWalConsistencyChecking(), InitPostmasterChildSlots(), InitPostmasterDeathWatchHandle(), InitProcessGlobals(), InitProcessLocalLatch(), initStringInfo(), IsBinaryUpgrade, IsPostmasterEnvironment, lfirst, list_free(), list_free_deep(), ListenAddresses, ListenServerPort(), ListenSockets, load_hba(), load_ident(), LoadedSSL, LocalProcessControlFile(), LOCK_FILE_LINE_LISTEN_ADDR, LOCK_FILE_LINE_PM_STATUS, LOCK_FILE_LINE_SOCKET_DIR, LOG, Log_destination, LOG_DESTINATION_STDERR, Log_destination_string, LOG_METAINFO_DATAFILE, Logging_collector, max_wal_senders, MaxConnections, MAXLISTEN, maybe_adjust_io_workers(), maybe_start_bgworkers(), MemoryContextSwitchTo(), message_level_is_interesting(), my_exec_path, MyProcPid, name, NIL, NumListenSockets, on_proc_exit(), optarg, opterr, optind, palloc(), parse_dispatch_option(), ParseLongOption(), pfree(), pg_hton16, PG_MODE_MASK_OWNER, PG_TEMP_FILES_DIR, PGC_POSTMASTER, PGC_S_ARGV, PGC_S_OVERRIDE, PGC_SUSET, PgStartTime, pgwin32_signal_initialize(), PM_STARTUP, PM_STATUS_STARTING, PostmasterContext, PostmasterPid, PostPortNumber, pqinitmask(), pqsignal, process_shared_preload_libraries(), process_shmem_requests(), progname, pstrdup(), RemoveLogrotateSignalFiles(), RemovePgTempFiles(), RemovePgTempFilesInDir(), RemovePromoteSignalFiles(), ReservedConnections, S_IRGRP, S_IROTH, S_IRUSR, S_IWUSR, secure_initialize(), SelectConfigFiles(), ServerLoop(), set_debug_options(), set_max_safe_fds(), set_plan_disabling_options(), SetConfigOption(), SIGALRM, SIGCHLD, SIGHUP, SIGPIPE, SIGQUIT, SIGUSR1, SIGUSR2, SplitDirectoriesString(), SplitGUCList(), StartChildProcess(), StartSysLogger(), STARTUP_RUNNING, StartupPMChild, StartupStatus, STATUS_OK, success, summarize_wal, SuperuserReservedConnections, sync_replication_slots, TopMemoryContext, UnBlockSig, Unix_socket_directories, unlink_external_pid_file(), UpdatePMState(), userDoption, value, wal_level, WAL_LEVEL_LOGICAL, WAL_LEVEL_MINIMAL, WARNING, whereToSendOutput, write_stderr, and XLogArchiveMode.

Referenced by main().

◆ PostmasterMarkPIDForWorkerNotify()

bool PostmasterMarkPIDForWorkerNotify ( int pid )

Definition at line 4454 of file postmaster.c.

{
    dlist_iter  iter;
    PMChild    *bp;
 
    dlist_foreach(iter, &ActiveChildList)
    {
        bp = dlist_container(PMChild, elem, iter.cur);
        if (bp->pid == pid)
        {
            bp->bgworker_notify = true;
            return true;
        }
    }
    return false;
}

References ActiveChildList, PMChild::bgworker_notify, dlist_iter::cur, dlist_container, dlist_foreach, and PMChild::pid.

Referenced by BackgroundWorkerStateChange().

◆ ReleasePostmasterChildSlot()

bool ReleasePostmasterChildSlot ( PMChild * pmchild )

Definition at line 252 of file pmchild.c.

{
    dlist_delete(&pmchild->elem);
    if (pmchild->bkend_type == B_DEAD_END_BACKEND)
    {
        elog(DEBUG2, "releasing dead-end backend");
        pfree(pmchild);
        return true;
    }
    else
    {
        PMChildPool *pool;
 
        elog(DEBUG2, "releasing pm child slot %d", pmchild->child_slot);
 
        /* WAL senders start out as regular backends, and share the pool */
        if (pmchild->bkend_type == B_WAL_SENDER)
            pool = &pmchild_pools[B_BACKEND];
        else
            pool = &pmchild_pools[pmchild->bkend_type];
 
        /* sanity check that we return the entry to the right pool */
        if (!(pmchild->child_slot >= pool->first_slotno &&
              pmchild->child_slot < pool->first_slotno + pool->size))
        {
            elog(ERROR, "pmchild freelist for backend type %d is corrupt",
                 pmchild->bkend_type);
        }
 
        dlist_push_head(&pool->freelist, &pmchild->elem);
        return MarkPostmasterChildSlotUnassigned(pmchild->child_slot);
    }
}

References B_BACKEND, B_DEAD_END_BACKEND, B_WAL_SENDER, PMChild::bkend_type, PMChild::child_slot, DEBUG2, dlist_delete(), dlist_push_head(), PMChild::elem, elog, ERROR, PMChildPool::first_slotno, PMChildPool::freelist, MarkPostmasterChildSlotUnassigned(), pfree(), pmchild_pools, and PMChildPool::size.

Referenced by BackendStartup(), CleanupBackend(), maybe_reap_io_worker(), process_pm_child_exit(), StartBackgroundWorker(), StartChildProcess(), and StartSysLogger().

Variable Documentation

◆ ActiveChildList

PGDLLIMPORT dlist_head ActiveChildList

extern

Definition at line 60 of file pmchild.c.

Referenced by AllocDeadEndChild(), AssignPostmasterChildSlot(), CountChildren(), FindPostmasterChildByPid(), InitPostmasterChildSlots(), PostmasterMarkPIDForWorkerNotify(), and SignalChildren().

◆ AuthenticationTimeout

PGDLLIMPORT int AuthenticationTimeout

extern

Definition at line 241 of file postmaster.c.

Referenced by BackendInitialize(), and PerformAuthentication().

◆ bonjour_name

PGDLLIMPORT char* bonjour_name

extern

Definition at line 246 of file postmaster.c.

Referenced by PostmasterMain().

◆ ClientAuthInProgress

PGDLLIMPORT bool ClientAuthInProgress

extern

Definition at line 372 of file postmaster.c.

Referenced by BackendInitialize(), PerformAuthentication(), ProcessInterrupts(), quickdie(), should_output_to_client(), and StatementTimeoutHandler().

◆ enable_bonjour

PGDLLIMPORT bool enable_bonjour

extern

Definition at line 245 of file postmaster.c.

Referenced by PostmasterMain().

◆ EnableSSL

PGDLLIMPORT bool EnableSSL

extern

Definition at line 238 of file postmaster.c.

Referenced by BackendMain(), parse_hba_line(), PostmasterMain(), and process_pm_reload_request().

◆ ListenAddresses

PGDLLIMPORT char* ListenAddresses

extern

Definition at line 209 of file postmaster.c.

Referenced by PostmasterMain().

◆ LoadedSSL

PGDLLIMPORT bool LoadedSSL

extern

Referenced by BackendMain(), PostmasterMain(), process_pm_reload_request(), ProcessSSLStartup(), and ProcessStartupPacket().

◆ log_hostname

PGDLLIMPORT bool log_hostname

extern

Definition at line 243 of file postmaster.c.

Referenced by BackendInitialize().

◆ MyClientSocket

PGDLLIMPORT struct ClientSocket* MyClientSocket

extern

Definition at line 50 of file globals.c.

Referenced by BackendMain(), and postmaster_child_launch().

◆ postmaster_alive_fds

PGDLLIMPORT int postmaster_alive_fds[2]

extern

Definition at line 483 of file postmaster.c.

Referenced by AddWaitEventToSet(), ClosePostmasterPorts(), InitPostmasterChild(), InitPostmasterDeathWatchHandle(), and PostmasterIsAliveInternal().

◆ PostPortNumber

PGDLLIMPORT int PostPortNumber

extern

Definition at line 203 of file postmaster.c.

Referenced by CreateLockFile(), and PostmasterMain().

◆ PreAuthDelay

PGDLLIMPORT int PreAuthDelay

extern

Definition at line 240 of file postmaster.c.

Referenced by BackendInitialize().

◆ progname

◆ redirection_done

PGDLLIMPORT bool redirection_done

extern

Definition at line 375 of file postmaster.c.

Referenced by send_message_to_server_log(), SysLogger_Start(), SysLoggerMain(), and write_console().

◆ remove_temp_files_after_crash

PGDLLIMPORT bool remove_temp_files_after_crash

extern

Definition at line 248 of file postmaster.c.

Referenced by PostmasterStateMachine().

◆ ReservedConnections

PGDLLIMPORT int ReservedConnections

extern

Definition at line 230 of file postmaster.c.

Referenced by InitPostgres(), and PostmasterMain().

◆ restart_after_crash

PGDLLIMPORT bool restart_after_crash

extern

Definition at line 247 of file postmaster.c.

Referenced by PostmasterStateMachine().

◆ send_abort_for_crash

PGDLLIMPORT bool send_abort_for_crash

extern

Definition at line 256 of file postmaster.c.

Referenced by HandleFatalError().

◆ send_abort_for_kill

PGDLLIMPORT bool send_abort_for_kill

extern

Definition at line 257 of file postmaster.c.

Referenced by ServerLoop().

◆ SuperuserReservedConnections

PGDLLIMPORT int SuperuserReservedConnections

extern

Definition at line 229 of file postmaster.c.

Referenced by InitPostgres(), and PostmasterMain().

◆ Unix_socket_directories

PGDLLIMPORT char* Unix_socket_directories

extern

Definition at line 206 of file postmaster.c.

Referenced by PostmasterMain().

◆ Unix_socket_group

PGDLLIMPORT char* Unix_socket_group

extern

Definition at line 107 of file pqcomm.c.

Referenced by Setup_AF_UNIX().

◆ Unix_socket_permissions

PGDLLIMPORT int Unix_socket_permissions

extern

Definition at line 106 of file pqcomm.c.

Referenced by Setup_AF_UNIX(), and show_unix_socket_permissions().

Data Structures

Macros

Typedefs

Enumerations

Functions

Variables

Macro Definition Documentation

◆ POSTMASTER_FD_OWN

◆ POSTMASTER_FD_WATCH

Typedef Documentation

◆ DispatchOption

Enumeration Type Documentation

◆ DispatchOption

Function Documentation

◆ AllocDeadEndChild()

◆ AssignPostmasterChildSlot()

◆ ClosePostmasterPorts()

◆ FindPostmasterChildByPid()

◆ InitPostmasterChildSlots()

◆ InitProcessGlobals()

◆ MaxLivePostmasterChildren()

◆ parse_dispatch_option()

◆ postmaster_child_launch()

◆ PostmasterChildName()

◆ PostmasterMain()

◆ PostmasterMarkPIDForWorkerNotify()

◆ ReleasePostmasterChildSlot()

Variable Documentation

◆ ActiveChildList

◆ AuthenticationTimeout

◆ bonjour_name

◆ ClientAuthInProgress

◆ enable_bonjour

◆ EnableSSL

◆ ListenAddresses

◆ LoadedSSL

◆ log_hostname

◆ MyClientSocket

◆ postmaster_alive_fds

◆ PostPortNumber

◆ PreAuthDelay

◆ progname

◆ redirection_done

◆ remove_temp_files_after_crash

◆ ReservedConnections

◆ restart_after_crash

◆ send_abort_for_crash

◆ send_abort_for_kill

◆ SuperuserReservedConnections

◆ Unix_socket_directories

◆ Unix_socket_group

◆ Unix_socket_permissions