postmaster.h File Reference

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

Include dependency graph for postmaster.h:

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

Go to the source code of 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, const 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 208 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 162 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 1855 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 274 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 86 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;
 
    /* Initialize them */
    slots = palloc(num_pmchild_slots * sizeof(PMChild));
    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 1932 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 70 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 240 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,
		const void *	startup_data,
		size_t	startup_data_len,
		struct ClientSocket *	client_sock
	)

Definition at line 229 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 211 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\"")));
 
    /*
     * 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) || defined(_MSC_VER)
        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, TopMemoryContext, UnBlockSig, Unix_socket_directories, unlink_external_pid_file(), UpdatePMState(), userDoption, value, wal_level, WAL_LEVEL_MINIMAL, WARNING, whereToSendOutput, write_stderr, and XLogArchiveMode.

Referenced by main().

PostmasterMarkPIDForWorkerNotify()

bool PostmasterMarkPIDForWorkerNotify

(

int

pid

)

Definition at line 4436 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 236 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 51 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

PGDLLIMPORT const char* progname

extern

Definition at line 44 of file main.c.

Referenced by _check_database_version(), BootstrapModeMain(), check_root(), checkControlFile(), cluster_all_databases(), cluster_one_database(), ConnectDatabase(), connectDatabase(), ConnectDatabaseAhx(), connectMaintenanceDatabase(), get_opts(), get_progname(), get_user_name_or_exit(), GetConnection(), help(), main(), ParallelSlotsSetup(), PostgresSingleUserMain(), PostmasterMain(), process_postgres_switches(), reindex_all_databases(), reindex_one_database(), restore_all_databases(), SelectConfigFiles(), set_dump_section(), sigTermHandler(), startup_hacks(), usage(), vacuum_all_databases(), and vacuum_one_database().

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().