LCOV - code coverage report
Current view: top level - src/backend/utils/init - postinit.c (source / functions) Coverage Total Hit
Test: PostgreSQL 19devel Lines: 91.4 % 371 339
Test Date: 2026-02-17 17:20:33 Functions: 95.5 % 22 21
Legend: Lines:     hit not hit

            Line data    Source code
       1              : /*-------------------------------------------------------------------------
       2              :  *
       3              :  * postinit.c
       4              :  *    postgres initialization utilities
       5              :  *
       6              :  * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
       7              :  * Portions Copyright (c) 1994, Regents of the University of California
       8              :  *
       9              :  *
      10              :  * IDENTIFICATION
      11              :  *    src/backend/utils/init/postinit.c
      12              :  *
      13              :  *
      14              :  *-------------------------------------------------------------------------
      15              :  */
      16              : #include "postgres.h"
      17              : 
      18              : #include <ctype.h>
      19              : #include <fcntl.h>
      20              : #include <unistd.h>
      21              : 
      22              : #include "access/genam.h"
      23              : #include "access/heapam.h"
      24              : #include "access/htup_details.h"
      25              : #include "access/session.h"
      26              : #include "access/tableam.h"
      27              : #include "access/xact.h"
      28              : #include "access/xlog.h"
      29              : #include "access/xloginsert.h"
      30              : #include "catalog/namespace.h"
      31              : #include "catalog/pg_authid.h"
      32              : #include "catalog/pg_collation.h"
      33              : #include "catalog/pg_database.h"
      34              : #include "catalog/pg_db_role_setting.h"
      35              : #include "catalog/pg_tablespace.h"
      36              : #include "libpq/auth.h"
      37              : #include "libpq/libpq-be.h"
      38              : #include "mb/pg_wchar.h"
      39              : #include "miscadmin.h"
      40              : #include "pgstat.h"
      41              : #include "postmaster/autovacuum.h"
      42              : #include "postmaster/postmaster.h"
      43              : #include "replication/slot.h"
      44              : #include "replication/slotsync.h"
      45              : #include "replication/walsender.h"
      46              : #include "storage/aio_subsys.h"
      47              : #include "storage/bufmgr.h"
      48              : #include "storage/fd.h"
      49              : #include "storage/ipc.h"
      50              : #include "storage/lmgr.h"
      51              : #include "storage/proc.h"
      52              : #include "storage/procarray.h"
      53              : #include "storage/procnumber.h"
      54              : #include "storage/procsignal.h"
      55              : #include "storage/sinvaladt.h"
      56              : #include "storage/smgr.h"
      57              : #include "storage/sync.h"
      58              : #include "tcop/backend_startup.h"
      59              : #include "tcop/tcopprot.h"
      60              : #include "utils/acl.h"
      61              : #include "utils/builtins.h"
      62              : #include "utils/fmgroids.h"
      63              : #include "utils/guc_hooks.h"
      64              : #include "utils/injection_point.h"
      65              : #include "utils/memutils.h"
      66              : #include "utils/pg_locale.h"
      67              : #include "utils/portal.h"
      68              : #include "utils/ps_status.h"
      69              : #include "utils/snapmgr.h"
      70              : #include "utils/syscache.h"
      71              : #include "utils/timeout.h"
      72              : 
      73              : /* has this backend called EmitConnectionWarnings()? */
      74              : static bool ConnectionWarningsEmitted;
      75              : 
      76              : /* content of warnings to send via EmitConnectionWarnings() */
      77              : static List *ConnectionWarningMessages;
      78              : static List *ConnectionWarningDetails;
      79              : 
      80              : static HeapTuple GetDatabaseTuple(const char *dbname);
      81              : static HeapTuple GetDatabaseTupleByOid(Oid dboid);
      82              : static void PerformAuthentication(Port *port);
      83              : static void CheckMyDatabase(const char *name, bool am_superuser, bool override_allow_connections);
      84              : static void ShutdownPostgres(int code, Datum arg);
      85              : static void StatementTimeoutHandler(void);
      86              : static void LockTimeoutHandler(void);
      87              : static void IdleInTransactionSessionTimeoutHandler(void);
      88              : static void TransactionTimeoutHandler(void);
      89              : static void IdleSessionTimeoutHandler(void);
      90              : static void IdleStatsUpdateTimeoutHandler(void);
      91              : static void ClientCheckTimeoutHandler(void);
      92              : static bool ThereIsAtLeastOneRole(void);
      93              : static void process_startup_options(Port *port, bool am_superuser);
      94              : static void process_settings(Oid databaseid, Oid roleid);
      95              : static void EmitConnectionWarnings(void);
      96              : 
      97              : 
      98              : /*** InitPostgres support ***/
      99              : 
     100              : 
     101              : /*
     102              :  * GetDatabaseTuple -- fetch the pg_database row for a database
     103              :  *
     104              :  * This is used during backend startup when we don't yet have any access to
     105              :  * system catalogs in general.  In the worst case, we can seqscan pg_database
     106              :  * using nothing but the hard-wired descriptor that relcache.c creates for
     107              :  * pg_database.  In more typical cases, relcache.c was able to load
     108              :  * descriptors for both pg_database and its indexes from the shared relcache
     109              :  * cache file, and so we can do an indexscan.  criticalSharedRelcachesBuilt
     110              :  * tells whether we got the cached descriptors.
     111              :  */
     112              : static HeapTuple
     113        13342 : GetDatabaseTuple(const char *dbname)
     114              : {
     115              :     HeapTuple   tuple;
     116              :     Relation    relation;
     117              :     SysScanDesc scan;
     118              :     ScanKeyData key[1];
     119              : 
     120              :     /*
     121              :      * form a scan key
     122              :      */
     123        13342 :     ScanKeyInit(&key[0],
     124              :                 Anum_pg_database_datname,
     125              :                 BTEqualStrategyNumber, F_NAMEEQ,
     126              :                 CStringGetDatum(dbname));
     127              : 
     128              :     /*
     129              :      * Open pg_database and fetch a tuple.  Force heap scan if we haven't yet
     130              :      * built the critical shared relcache entries (i.e., we're starting up
     131              :      * without a shared relcache cache file).
     132              :      */
     133        13342 :     relation = table_open(DatabaseRelationId, AccessShareLock);
     134        13342 :     scan = systable_beginscan(relation, DatabaseNameIndexId,
     135              :                               criticalSharedRelcachesBuilt,
     136              :                               NULL,
     137              :                               1, key);
     138              : 
     139        13342 :     tuple = systable_getnext(scan);
     140              : 
     141              :     /* Must copy tuple before releasing buffer */
     142        13342 :     if (HeapTupleIsValid(tuple))
     143        13333 :         tuple = heap_copytuple(tuple);
     144              : 
     145              :     /* all done */
     146        13342 :     systable_endscan(scan);
     147        13342 :     table_close(relation, AccessShareLock);
     148              : 
     149        13342 :     return tuple;
     150              : }
     151              : 
     152              : /*
     153              :  * GetDatabaseTupleByOid -- as above, but search by database OID
     154              :  */
     155              : static HeapTuple
     156        17101 : GetDatabaseTupleByOid(Oid dboid)
     157              : {
     158              :     HeapTuple   tuple;
     159              :     Relation    relation;
     160              :     SysScanDesc scan;
     161              :     ScanKeyData key[1];
     162              : 
     163              :     /*
     164              :      * form a scan key
     165              :      */
     166        17101 :     ScanKeyInit(&key[0],
     167              :                 Anum_pg_database_oid,
     168              :                 BTEqualStrategyNumber, F_OIDEQ,
     169              :                 ObjectIdGetDatum(dboid));
     170              : 
     171              :     /*
     172              :      * Open pg_database and fetch a tuple.  Force heap scan if we haven't yet
     173              :      * built the critical shared relcache entries (i.e., we're starting up
     174              :      * without a shared relcache cache file).
     175              :      */
     176        17101 :     relation = table_open(DatabaseRelationId, AccessShareLock);
     177        17101 :     scan = systable_beginscan(relation, DatabaseOidIndexId,
     178              :                               criticalSharedRelcachesBuilt,
     179              :                               NULL,
     180              :                               1, key);
     181              : 
     182        17101 :     tuple = systable_getnext(scan);
     183              : 
     184              :     /* Must copy tuple before releasing buffer */
     185        17101 :     if (HeapTupleIsValid(tuple))
     186        17101 :         tuple = heap_copytuple(tuple);
     187              : 
     188              :     /* all done */
     189        17101 :     systable_endscan(scan);
     190        17101 :     table_close(relation, AccessShareLock);
     191              : 
     192        17101 :     return tuple;
     193              : }
     194              : 
     195              : 
     196              : /*
     197              :  * PerformAuthentication -- authenticate a remote client
     198              :  *
     199              :  * returns: nothing.  Will not return at all if there's any failure.
     200              :  */
     201              : static void
     202        13817 : PerformAuthentication(Port *port)
     203              : {
     204              :     /* This should be set already, but let's make sure */
     205        13817 :     ClientAuthInProgress = true;    /* limit visibility of log messages */
     206              : 
     207              :     /*
     208              :      * In EXEC_BACKEND case, we didn't inherit the contents of pg_hba.conf
     209              :      * etcetera from the postmaster, and have to load them ourselves.
     210              :      *
     211              :      * FIXME: [fork/exec] Ugh.  Is there a way around this overhead?
     212              :      */
     213              : #ifdef EXEC_BACKEND
     214              : 
     215              :     /*
     216              :      * load_hba() and load_ident() want to work within the PostmasterContext,
     217              :      * so create that if it doesn't exist (which it won't).  We'll delete it
     218              :      * again later, in PostgresMain.
     219              :      */
     220              :     if (PostmasterContext == NULL)
     221              :         PostmasterContext = AllocSetContextCreate(TopMemoryContext,
     222              :                                                   "Postmaster",
     223              :                                                   ALLOCSET_DEFAULT_SIZES);
     224              : 
     225              :     if (!load_hba())
     226              :     {
     227              :         /*
     228              :          * It makes no sense to continue if we fail to load the HBA file,
     229              :          * since there is no way to connect to the database in this case.
     230              :          */
     231              :         ereport(FATAL,
     232              :         /* translator: %s is a configuration file */
     233              :                 (errmsg("could not load %s", HbaFileName)));
     234              :     }
     235              : 
     236              :     if (!load_ident())
     237              :     {
     238              :         /*
     239              :          * It is ok to continue if we fail to load the IDENT file, although it
     240              :          * means that you cannot log in using any of the authentication
     241              :          * methods that need a user name mapping. load_ident() already logged
     242              :          * the details of error to the log.
     243              :          */
     244              :     }
     245              : #endif
     246              : 
     247              :     /* Capture authentication start time for logging */
     248        13817 :     conn_timing.auth_start = GetCurrentTimestamp();
     249              : 
     250              :     /*
     251              :      * Set up a timeout in case a buggy or malicious client fails to respond
     252              :      * during authentication.  Since we're inside a transaction and might do
     253              :      * database access, we have to use the statement_timeout infrastructure.
     254              :      */
     255        13817 :     enable_timeout_after(STATEMENT_TIMEOUT, AuthenticationTimeout * 1000);
     256              : 
     257              :     /*
     258              :      * Now perform authentication exchange.
     259              :      */
     260        13817 :     set_ps_display("authentication");
     261        13817 :     ClientAuthentication(port); /* might not return, if failure */
     262              : 
     263              :     /*
     264              :      * Done with authentication.  Disable the timeout, and log if needed.
     265              :      */
     266        13750 :     disable_timeout(STATEMENT_TIMEOUT, false);
     267              : 
     268              :     /* Capture authentication end time for logging */
     269        13750 :     conn_timing.auth_end = GetCurrentTimestamp();
     270              : 
     271        13750 :     if (log_connections & LOG_CONNECTION_AUTHORIZATION)
     272              :     {
     273              :         StringInfoData logmsg;
     274              : 
     275          219 :         initStringInfo(&logmsg);
     276          219 :         if (am_walsender)
     277            0 :             appendStringInfo(&logmsg, _("replication connection authorized: user=%s"),
     278              :                              port->user_name);
     279              :         else
     280          219 :             appendStringInfo(&logmsg, _("connection authorized: user=%s"),
     281              :                              port->user_name);
     282          219 :         if (!am_walsender)
     283          219 :             appendStringInfo(&logmsg, _(" database=%s"), port->database_name);
     284              : 
     285          219 :         if (port->application_name != NULL)
     286          219 :             appendStringInfo(&logmsg, _(" application_name=%s"),
     287              :                              port->application_name);
     288              : 
     289              : #ifdef USE_SSL
     290          219 :         if (port->ssl_in_use)
     291           89 :             appendStringInfo(&logmsg, _(" SSL enabled (protocol=%s, cipher=%s, bits=%d)"),
     292              :                              be_tls_get_version(port),
     293              :                              be_tls_get_cipher(port),
     294              :                              be_tls_get_cipher_bits(port));
     295              : #endif
     296              : #ifdef ENABLE_GSS
     297              :         if (port->gss)
     298              :         {
     299              :             const char *princ = be_gssapi_get_princ(port);
     300              : 
     301              :             if (princ)
     302              :                 appendStringInfo(&logmsg,
     303              :                                  _(" GSS (authenticated=%s, encrypted=%s, delegated_credentials=%s, principal=%s)"),
     304              :                                  be_gssapi_get_auth(port) ? _("yes") : _("no"),
     305              :                                  be_gssapi_get_enc(port) ? _("yes") : _("no"),
     306              :                                  be_gssapi_get_delegation(port) ? _("yes") : _("no"),
     307              :                                  princ);
     308              :             else
     309              :                 appendStringInfo(&logmsg,
     310              :                                  _(" GSS (authenticated=%s, encrypted=%s, delegated_credentials=%s)"),
     311              :                                  be_gssapi_get_auth(port) ? _("yes") : _("no"),
     312              :                                  be_gssapi_get_enc(port) ? _("yes") : _("no"),
     313              :                                  be_gssapi_get_delegation(port) ? _("yes") : _("no"));
     314              :         }
     315              : #endif
     316              : 
     317          219 :         ereport(LOG, errmsg_internal("%s", logmsg.data));
     318          219 :         pfree(logmsg.data);
     319              :     }
     320              : 
     321        13750 :     set_ps_display("startup");
     322              : 
     323        13750 :     ClientAuthInProgress = false;   /* client_min_messages is active now */
     324        13750 : }
     325              : 
     326              : 
     327              : /*
     328              :  * CheckMyDatabase -- fetch information from the pg_database entry for our DB
     329              :  */
     330              : static void
     331        17094 : CheckMyDatabase(const char *name, bool am_superuser, bool override_allow_connections)
     332              : {
     333              :     HeapTuple   tup;
     334              :     Form_pg_database dbform;
     335              :     Datum       datum;
     336              :     bool        isnull;
     337              :     char       *collate;
     338              :     char       *ctype;
     339              : 
     340              :     /* Fetch our pg_database row normally, via syscache */
     341        17094 :     tup = SearchSysCache1(DATABASEOID, ObjectIdGetDatum(MyDatabaseId));
     342        17094 :     if (!HeapTupleIsValid(tup))
     343            0 :         elog(ERROR, "cache lookup failed for database %u", MyDatabaseId);
     344        17094 :     dbform = (Form_pg_database) GETSTRUCT(tup);
     345              : 
     346              :     /* This recheck is strictly paranoia */
     347        17094 :     if (strcmp(name, NameStr(dbform->datname)) != 0)
     348            0 :         ereport(FATAL,
     349              :                 (errcode(ERRCODE_UNDEFINED_DATABASE),
     350              :                  errmsg("database \"%s\" has disappeared from pg_database",
     351              :                         name),
     352              :                  errdetail("Database OID %u now seems to belong to \"%s\".",
     353              :                            MyDatabaseId, NameStr(dbform->datname))));
     354              : 
     355              :     /*
     356              :      * Check permissions to connect to the database.
     357              :      *
     358              :      * These checks are not enforced when in standalone mode, so that there is
     359              :      * a way to recover from disabling all access to all databases, for
     360              :      * example "UPDATE pg_database SET datallowconn = false;".
     361              :      */
     362        17094 :     if (IsUnderPostmaster)
     363              :     {
     364              :         /*
     365              :          * Check that the database is currently allowing connections.
     366              :          * (Background processes can override this test and the next one by
     367              :          * setting override_allow_connections.)
     368              :          */
     369        17024 :         if (!dbform->datallowconn && !override_allow_connections)
     370            1 :             ereport(FATAL,
     371              :                     (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
     372              :                      errmsg("database \"%s\" is not currently accepting connections",
     373              :                             name)));
     374              : 
     375              :         /*
     376              :          * Check privilege to connect to the database.  (The am_superuser test
     377              :          * is redundant, but since we have the flag, might as well check it
     378              :          * and save a few cycles.)
     379              :          */
     380        17302 :         if (!am_superuser && !override_allow_connections &&
     381          279 :             object_aclcheck(DatabaseRelationId, MyDatabaseId, GetUserId(),
     382              :                             ACL_CONNECT) != ACLCHECK_OK)
     383            0 :             ereport(FATAL,
     384              :                     (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
     385              :                      errmsg("permission denied for database \"%s\"", name),
     386              :                      errdetail("User does not have CONNECT privilege.")));
     387              : 
     388              :         /*
     389              :          * Check connection limit for this database.  We enforce the limit
     390              :          * only for regular backends, since other process types have their own
     391              :          * PGPROC pools.
     392              :          *
     393              :          * There is a race condition here --- we create our PGPROC before
     394              :          * checking for other PGPROCs.  If two backends did this at about the
     395              :          * same time, they might both think they were over the limit, while
     396              :          * ideally one should succeed and one fail.  Getting that to work
     397              :          * exactly seems more trouble than it is worth, however; instead we
     398              :          * just document that the connection limit is approximate.
     399              :          */
     400        17023 :         if (dbform->datconnlimit >= 0 &&
     401            0 :             AmRegularBackendProcess() &&
     402            0 :             !am_superuser &&
     403            0 :             CountDBConnections(MyDatabaseId) > dbform->datconnlimit)
     404            0 :             ereport(FATAL,
     405              :                     (errcode(ERRCODE_TOO_MANY_CONNECTIONS),
     406              :                      errmsg("too many connections for database \"%s\"",
     407              :                             name)));
     408              :     }
     409              : 
     410              :     /*
     411              :      * OK, we're golden.  Next to-do item is to save the encoding info out of
     412              :      * the pg_database tuple.
     413              :      */
     414        17093 :     SetDatabaseEncoding(dbform->encoding);
     415              :     /* Record it as a GUC internal option, too */
     416        17093 :     SetConfigOption("server_encoding", GetDatabaseEncodingName(),
     417              :                     PGC_INTERNAL, PGC_S_DYNAMIC_DEFAULT);
     418              :     /* If we have no other source of client_encoding, use server encoding */
     419        17093 :     SetConfigOption("client_encoding", GetDatabaseEncodingName(),
     420              :                     PGC_BACKEND, PGC_S_DYNAMIC_DEFAULT);
     421              : 
     422              :     /* assign locale variables */
     423        17093 :     datum = SysCacheGetAttrNotNull(DATABASEOID, tup, Anum_pg_database_datcollate);
     424        17093 :     collate = TextDatumGetCString(datum);
     425        17093 :     datum = SysCacheGetAttrNotNull(DATABASEOID, tup, Anum_pg_database_datctype);
     426        17093 :     ctype = TextDatumGetCString(datum);
     427              : 
     428              :     /*
     429              :      * Historically, we set LC_COLLATE from datcollate, as well. That's no
     430              :      * longer necessary because all collation behavior is handled through
     431              :      * pg_locale_t.
     432              :      */
     433              : 
     434        17093 :     if (pg_perm_setlocale(LC_CTYPE, ctype) == NULL)
     435            0 :         ereport(FATAL,
     436              :                 (errmsg("database locale is incompatible with operating system"),
     437              :                  errdetail("The database was initialized with LC_CTYPE \"%s\", "
     438              :                            " which is not recognized by setlocale().", ctype),
     439              :                  errhint("Recreate the database with another locale or install the missing locale.")));
     440              : 
     441        17093 :     init_database_collation();
     442              : 
     443              :     /*
     444              :      * Check collation version.  See similar code in
     445              :      * pg_newlocale_from_collation().  Note that here we warn instead of error
     446              :      * in any case, so that we don't prevent connecting.
     447              :      */
     448        17091 :     datum = SysCacheGetAttr(DATABASEOID, tup, Anum_pg_database_datcollversion,
     449              :                             &isnull);
     450        17091 :     if (!isnull)
     451              :     {
     452              :         char       *actual_versionstr;
     453              :         char       *collversionstr;
     454              :         char       *locale;
     455              : 
     456        16227 :         collversionstr = TextDatumGetCString(datum);
     457              : 
     458        16227 :         if (dbform->datlocprovider == COLLPROVIDER_LIBC)
     459        15313 :             locale = collate;
     460              :         else
     461              :         {
     462          914 :             datum = SysCacheGetAttrNotNull(DATABASEOID, tup, Anum_pg_database_datlocale);
     463          914 :             locale = TextDatumGetCString(datum);
     464              :         }
     465              : 
     466        16227 :         actual_versionstr = get_collation_actual_version(dbform->datlocprovider, locale);
     467        16227 :         if (!actual_versionstr)
     468              :             /* should not happen */
     469            0 :             elog(WARNING,
     470              :                  "database \"%s\" has no actual collation version, but a version was recorded",
     471              :                  name);
     472        16227 :         else if (strcmp(actual_versionstr, collversionstr) != 0)
     473            0 :             ereport(WARNING,
     474              :                     (errmsg("database \"%s\" has a collation version mismatch",
     475              :                             name),
     476              :                      errdetail("The database was created using collation version %s, "
     477              :                                "but the operating system provides version %s.",
     478              :                                collversionstr, actual_versionstr),
     479              :                      errhint("Rebuild all objects in this database that use the default collation and run "
     480              :                              "ALTER DATABASE %s REFRESH COLLATION VERSION, "
     481              :                              "or build PostgreSQL with the right library version.",
     482              :                              quote_identifier(name))));
     483              :     }
     484              : 
     485        17091 :     ReleaseSysCache(tup);
     486        17091 : }
     487              : 
     488              : 
     489              : /*
     490              :  * pg_split_opts -- split a string of options and append it to an argv array
     491              :  *
     492              :  * The caller is responsible for ensuring the argv array is large enough.  The
     493              :  * maximum possible number of arguments added by this routine is
     494              :  * (strlen(optstr) + 1) / 2.
     495              :  *
     496              :  * Because some option values can contain spaces we allow escaping using
     497              :  * backslashes, with \\ representing a literal backslash.
     498              :  */
     499              : void
     500         3875 : pg_split_opts(char **argv, int *argcp, const char *optstr)
     501              : {
     502              :     StringInfoData s;
     503              : 
     504         3875 :     initStringInfo(&s);
     505              : 
     506        14257 :     while (*optstr)
     507              :     {
     508        10382 :         bool        last_was_escape = false;
     509              : 
     510        10382 :         resetStringInfo(&s);
     511              : 
     512              :         /* skip over leading space */
     513        19837 :         while (isspace((unsigned char) *optstr))
     514         9455 :             optstr++;
     515              : 
     516        10382 :         if (*optstr == '\0')
     517            0 :             break;
     518              : 
     519              :         /*
     520              :          * Parse a single option, stopping at the first space, unless it's
     521              :          * escaped.
     522              :          */
     523       158275 :         while (*optstr)
     524              :         {
     525       154400 :             if (isspace((unsigned char) *optstr) && !last_was_escape)
     526         6507 :                 break;
     527              : 
     528       147893 :             if (!last_was_escape && *optstr == '\\')
     529           20 :                 last_was_escape = true;
     530              :             else
     531              :             {
     532       147873 :                 last_was_escape = false;
     533       147873 :                 appendStringInfoChar(&s, *optstr);
     534              :             }
     535              : 
     536       147893 :             optstr++;
     537              :         }
     538              : 
     539              :         /* now store the option in the next argv[] position */
     540        10382 :         argv[(*argcp)++] = pstrdup(s.data);
     541              :     }
     542              : 
     543         3875 :     pfree(s.data);
     544         3875 : }
     545              : 
     546              : /*
     547              :  * Initialize MaxBackends value from config options.
     548              :  *
     549              :  * This must be called after modules have had the chance to alter GUCs in
     550              :  * shared_preload_libraries and before shared memory size is determined.
     551              :  *
     552              :  * Note that in EXEC_BACKEND environment, the value is passed down from
     553              :  * postmaster to subprocesses via BackendParameters in SubPostmasterMain; only
     554              :  * postmaster itself and processes not under postmaster control should call
     555              :  * this.
     556              :  */
     557              : void
     558         1138 : InitializeMaxBackends(void)
     559              : {
     560              :     Assert(MaxBackends == 0);
     561              : 
     562              :     /* Note that this does not include "auxiliary" processes */
     563         1138 :     MaxBackends = MaxConnections + autovacuum_worker_slots +
     564         1138 :         max_worker_processes + max_wal_senders + NUM_SPECIAL_WORKER_PROCS;
     565              : 
     566         1138 :     if (MaxBackends > MAX_BACKENDS)
     567            0 :         ereport(ERROR,
     568              :                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
     569              :                  errmsg("too many server processes configured"),
     570              :                  errdetail("\"max_connections\" (%d) plus \"autovacuum_worker_slots\" (%d) plus \"max_worker_processes\" (%d) plus \"max_wal_senders\" (%d) must be less than %d.",
     571              :                            MaxConnections, autovacuum_worker_slots,
     572              :                            max_worker_processes, max_wal_senders,
     573              :                            MAX_BACKENDS - (NUM_SPECIAL_WORKER_PROCS - 1))));
     574         1138 : }
     575              : 
     576              : /*
     577              :  * Initialize the number of fast-path lock slots in PGPROC.
     578              :  *
     579              :  * This must be called after modules have had the chance to alter GUCs in
     580              :  * shared_preload_libraries and before shared memory size is determined.
     581              :  */
     582              : void
     583         1138 : InitializeFastPathLocks(void)
     584              : {
     585              :     /* Should be initialized only once. */
     586              :     Assert(FastPathLockGroupsPerBackend == 0);
     587              : 
     588              :     /*
     589              :      * Based on the max_locks_per_transaction GUC, as that's a good indicator
     590              :      * of the expected number of locks, figure out the value for
     591              :      * FastPathLockGroupsPerBackend.  This must be a power-of-two.  We cap the
     592              :      * value at FP_LOCK_GROUPS_PER_BACKEND_MAX and insist the value is at
     593              :      * least 1.
     594              :      *
     595              :      * The default max_locks_per_transaction = 64 means 4 groups by default.
     596              :      */
     597         1138 :     FastPathLockGroupsPerBackend =
     598         1138 :         Max(Min(pg_nextpower2_32(max_locks_per_xact) / FP_LOCK_SLOTS_PER_GROUP,
     599              :                 FP_LOCK_GROUPS_PER_BACKEND_MAX), 1);
     600              : 
     601              :     /* Validate we did get a power-of-two */
     602              :     Assert(FastPathLockGroupsPerBackend ==
     603              :            pg_nextpower2_32(FastPathLockGroupsPerBackend));
     604         1138 : }
     605              : 
     606              : /*
     607              :  * Early initialization of a backend (either standalone or under postmaster).
     608              :  * This happens even before InitPostgres.
     609              :  *
     610              :  * This is separate from InitPostgres because it is also called by auxiliary
     611              :  * processes, such as the background writer process, which may not call
     612              :  * InitPostgres at all.
     613              :  */
     614              : void
     615        23122 : BaseInit(void)
     616              : {
     617              :     Assert(MyProc != NULL);
     618              : 
     619              :     /*
     620              :      * Initialize our input/output/debugging file descriptors.
     621              :      */
     622        23122 :     DebugFileOpen();
     623              : 
     624              :     /*
     625              :      * Initialize file access. Done early so other subsystems can access
     626              :      * files.
     627              :      */
     628        23122 :     InitFileAccess();
     629              : 
     630              :     /*
     631              :      * Initialize statistics reporting. This needs to happen early to ensure
     632              :      * that pgstat's shutdown callback runs after the shutdown callbacks of
     633              :      * all subsystems that can produce stats (like e.g. transaction commits
     634              :      * can).
     635              :      */
     636        23122 :     pgstat_initialize();
     637              : 
     638              :     /*
     639              :      * Initialize AIO before infrastructure that might need to actually
     640              :      * execute AIO.
     641              :      */
     642        23122 :     pgaio_init_backend();
     643              : 
     644              :     /* Do local initialization of storage and buffer managers */
     645        23122 :     InitSync();
     646        23122 :     smgrinit();
     647        23122 :     InitBufferManagerAccess();
     648              : 
     649              :     /*
     650              :      * Initialize temporary file access after pgstat, so that the temporary
     651              :      * file shutdown hook can report temporary file statistics.
     652              :      */
     653        23122 :     InitTemporaryFileAccess();
     654              : 
     655              :     /*
     656              :      * Initialize local buffers for WAL record construction, in case we ever
     657              :      * try to insert XLOG.
     658              :      */
     659        23122 :     InitXLogInsert();
     660              : 
     661              :     /* Initialize lock manager's local structs */
     662        23122 :     InitLockManagerAccess();
     663              : 
     664              :     /* Initialize logical info WAL logging state */
     665        23122 :     InitializeProcessXLogLogicalInfo();
     666              : 
     667              :     /*
     668              :      * Initialize replication slots after pgstat. The exit hook might need to
     669              :      * drop ephemeral slots, which in turn triggers stats reporting.
     670              :      */
     671        23122 :     ReplicationSlotInitialize();
     672        23122 : }
     673              : 
     674              : 
     675              : /* --------------------------------
     676              :  * InitPostgres
     677              :  *      Initialize POSTGRES.
     678              :  *
     679              :  * Parameters:
     680              :  *  in_dbname, dboid: specify database to connect to, as described below
     681              :  *  username, useroid: specify role to connect as, as described below
     682              :  *  flags:
     683              :  *    - INIT_PG_LOAD_SESSION_LIBS to honor [session|local]_preload_libraries.
     684              :  *    - INIT_PG_OVERRIDE_ALLOW_CONNS to connect despite !datallowconn.
     685              :  *    - INIT_PG_OVERRIDE_ROLE_LOGIN to connect despite !rolcanlogin.
     686              :  *  out_dbname: optional output parameter, see below; pass NULL if not used
     687              :  *
     688              :  * The database can be specified by name, using the in_dbname parameter, or by
     689              :  * OID, using the dboid parameter.  Specify NULL or InvalidOid respectively
     690              :  * for the unused parameter.  If dboid is provided, the actual database
     691              :  * name can be returned to the caller in out_dbname.  If out_dbname isn't
     692              :  * NULL, it must point to a buffer of size NAMEDATALEN.
     693              :  *
     694              :  * Similarly, the role can be passed by name, using the username parameter,
     695              :  * or by OID using the useroid parameter.
     696              :  *
     697              :  * In bootstrap mode the database and username parameters are NULL/InvalidOid.
     698              :  * The autovacuum launcher process doesn't specify these parameters either,
     699              :  * because it only goes far enough to be able to read pg_database; it doesn't
     700              :  * connect to any particular database.  An autovacuum worker specifies a
     701              :  * database but not a username; conversely, a physical walsender specifies
     702              :  * username but not database.
     703              :  *
     704              :  * By convention, INIT_PG_LOAD_SESSION_LIBS should be passed in "flags" in
     705              :  * "interactive" sessions (including standalone backends), but not in
     706              :  * background processes such as autovacuum.  Note in particular that it
     707              :  * shouldn't be true in parallel worker processes; those have another
     708              :  * mechanism for replicating their leader's set of loaded libraries.
     709              :  *
     710              :  * We expect that InitProcess() was already called, so we already have a
     711              :  * PGPROC struct ... but it's not completely filled in yet.
     712              :  *
     713              :  * Note:
     714              :  *      Be very careful with the order of calls in the InitPostgres function.
     715              :  * --------------------------------
     716              :  */
     717              : void
     718        18578 : InitPostgres(const char *in_dbname, Oid dboid,
     719              :              const char *username, Oid useroid,
     720              :              bits32 flags,
     721              :              char *out_dbname)
     722              : {
     723        18578 :     bool        bootstrap = IsBootstrapProcessingMode();
     724              :     bool        am_superuser;
     725              :     char       *fullpath;
     726              :     char        dbname[NAMEDATALEN];
     727        18578 :     int         nfree = 0;
     728              : 
     729        18578 :     elog(DEBUG3, "InitPostgres");
     730              : 
     731              :     /*
     732              :      * Add my PGPROC struct to the ProcArray.
     733              :      *
     734              :      * Once I have done this, I am visible to other backends!
     735              :      */
     736        18578 :     InitProcessPhase2();
     737              : 
     738              :     /* Initialize status reporting */
     739        18578 :     pgstat_beinit();
     740              : 
     741              :     /*
     742              :      * And initialize an entry in the PgBackendStatus array.  That way, if
     743              :      * LWLocks or third-party authentication should happen to hang, it is
     744              :      * possible to retrieve some information about what is going on.
     745              :      */
     746        18578 :     if (!bootstrap)
     747              :     {
     748        18527 :         pgstat_bestart_initial();
     749        18527 :         INJECTION_POINT("init-pre-auth", NULL);
     750              :     }
     751              : 
     752              :     /*
     753              :      * Initialize my entry in the shared-invalidation manager's array of
     754              :      * per-backend data.
     755              :      */
     756        18578 :     SharedInvalBackendInit(false);
     757              : 
     758        18578 :     ProcSignalInit(MyCancelKey, MyCancelKeyLength);
     759              : 
     760              :     /*
     761              :      * Also set up timeout handlers needed for backend operation.  We need
     762              :      * these in every case except bootstrap.
     763              :      */
     764        18578 :     if (!bootstrap)
     765              :     {
     766        18527 :         RegisterTimeout(DEADLOCK_TIMEOUT, CheckDeadLockAlert);
     767        18527 :         RegisterTimeout(STATEMENT_TIMEOUT, StatementTimeoutHandler);
     768        18527 :         RegisterTimeout(LOCK_TIMEOUT, LockTimeoutHandler);
     769        18527 :         RegisterTimeout(IDLE_IN_TRANSACTION_SESSION_TIMEOUT,
     770              :                         IdleInTransactionSessionTimeoutHandler);
     771        18527 :         RegisterTimeout(TRANSACTION_TIMEOUT, TransactionTimeoutHandler);
     772        18527 :         RegisterTimeout(IDLE_SESSION_TIMEOUT, IdleSessionTimeoutHandler);
     773        18527 :         RegisterTimeout(CLIENT_CONNECTION_CHECK_TIMEOUT, ClientCheckTimeoutHandler);
     774        18527 :         RegisterTimeout(IDLE_STATS_UPDATE_TIMEOUT,
     775              :                         IdleStatsUpdateTimeoutHandler);
     776              :     }
     777              : 
     778              :     /*
     779              :      * If this is either a bootstrap process or a standalone backend, start up
     780              :      * the XLOG machinery, and register to have it closed down at exit. In
     781              :      * other cases, the startup process is responsible for starting up the
     782              :      * XLOG machinery, and the checkpointer for closing it down.
     783              :      */
     784        18578 :     if (!IsUnderPostmaster)
     785              :     {
     786              :         /*
     787              :          * We don't yet have an aux-process resource owner, but StartupXLOG
     788              :          * and ShutdownXLOG will need one.  Hence, create said resource owner
     789              :          * (and register a callback to clean it up after ShutdownXLOG runs).
     790              :          */
     791          121 :         CreateAuxProcessResourceOwner();
     792              : 
     793          121 :         StartupXLOG();
     794              :         /* Release (and warn about) any buffer pins leaked in StartupXLOG */
     795          121 :         ReleaseAuxProcessResources(true);
     796              :         /* Reset CurrentResourceOwner to nothing for the moment */
     797          121 :         CurrentResourceOwner = NULL;
     798              : 
     799              :         /*
     800              :          * Use before_shmem_exit() so that ShutdownXLOG() can rely on DSM
     801              :          * segments etc to work (which in turn is required for pgstats).
     802              :          */
     803          121 :         before_shmem_exit(pgstat_before_server_shutdown, 0);
     804          121 :         before_shmem_exit(ShutdownXLOG, 0);
     805              :     }
     806              : 
     807              :     /*
     808              :      * Initialize the relation cache and the system catalog caches.  Note that
     809              :      * no catalog access happens here; we only set up the hashtable structure.
     810              :      * We must do this before starting a transaction because transaction abort
     811              :      * would try to touch these hashtables.
     812              :      */
     813        18578 :     RelationCacheInitialize();
     814        18578 :     InitCatalogCache();
     815        18578 :     InitPlanCache();
     816              : 
     817              :     /* Initialize portal manager */
     818        18578 :     EnablePortalManager();
     819              : 
     820              :     /*
     821              :      * Load relcache entries for the shared system catalogs.  This must create
     822              :      * at least entries for pg_database and catalogs used for authentication.
     823              :      */
     824        18578 :     RelationCacheInitializePhase2();
     825              : 
     826              :     /*
     827              :      * Set up process-exit callback to do pre-shutdown cleanup.  This is one
     828              :      * of the first before_shmem_exit callbacks we register; thus, this will
     829              :      * be one of the last things we do before low-level modules like the
     830              :      * buffer manager begin to close down.  We need to have this in place
     831              :      * before we begin our first transaction --- if we fail during the
     832              :      * initialization transaction, as is entirely possible, we need the
     833              :      * AbortTransaction call to clean up.
     834              :      */
     835        18578 :     before_shmem_exit(ShutdownPostgres, 0);
     836              : 
     837              :     /* The autovacuum launcher is done here */
     838        18578 :     if (AmAutoVacuumLauncherProcess())
     839              :     {
     840              :         /* fill in the remainder of this entry in the PgBackendStatus array */
     841          417 :         pgstat_bestart_final();
     842              : 
     843         1343 :         return;
     844              :     }
     845              : 
     846              :     /*
     847              :      * Start a new transaction here before first access to db.
     848              :      */
     849        18161 :     if (!bootstrap)
     850              :     {
     851              :         /* statement_timestamp must be set for timeouts to work correctly */
     852        18110 :         SetCurrentStatementStartTimestamp();
     853        18110 :         StartTransactionCommand();
     854              : 
     855              :         /*
     856              :          * transaction_isolation will have been set to the default by the
     857              :          * above.  If the default is "serializable", and we are in hot
     858              :          * standby, we will fail if we don't change it to something lower.
     859              :          * Fortunately, "read committed" is plenty good enough.
     860              :          */
     861        18110 :         XactIsoLevel = XACT_READ_COMMITTED;
     862              :     }
     863              : 
     864              :     /*
     865              :      * Perform client authentication if necessary, then figure out our
     866              :      * postgres user ID, and see if we are a superuser.
     867              :      *
     868              :      * In standalone mode, autovacuum worker processes and slot sync worker
     869              :      * process, we use a fixed ID, otherwise we figure it out from the
     870              :      * authenticated user name.
     871              :      */
     872        18161 :     if (bootstrap || AmAutoVacuumWorkerProcess() || AmLogicalSlotSyncWorkerProcess())
     873              :     {
     874         1779 :         InitializeSessionUserIdStandalone();
     875         1779 :         am_superuser = true;
     876              :     }
     877        16382 :     else if (!IsUnderPostmaster)
     878              :     {
     879           70 :         InitializeSessionUserIdStandalone();
     880           70 :         am_superuser = true;
     881           70 :         if (!ThereIsAtLeastOneRole())
     882            0 :             ereport(WARNING,
     883              :                     (errcode(ERRCODE_UNDEFINED_OBJECT),
     884              :                      errmsg("no roles are defined in this database system"),
     885              :                      errhint("You should immediately run CREATE USER \"%s\" SUPERUSER;.",
     886              :                              username != NULL ? username : "postgres")));
     887              :     }
     888        16312 :     else if (AmBackgroundWorkerProcess())
     889              :     {
     890         2495 :         if (username == NULL && !OidIsValid(useroid))
     891              :         {
     892          456 :             InitializeSessionUserIdStandalone();
     893          456 :             am_superuser = true;
     894              :         }
     895              :         else
     896              :         {
     897         2039 :             InitializeSessionUserId(username, useroid,
     898         2039 :                                     (flags & INIT_PG_OVERRIDE_ROLE_LOGIN) != 0);
     899         2038 :             am_superuser = superuser();
     900              :         }
     901              :     }
     902              :     else
     903              :     {
     904              :         /* normal multiuser case */
     905              :         Assert(MyProcPort != NULL);
     906        13817 :         PerformAuthentication(MyProcPort);
     907        13750 :         InitializeSessionUserId(username, useroid, false);
     908              :         /* ensure that auth_method is actually valid, aka authn_id is not NULL */
     909        13746 :         if (MyClientConnectionInfo.authn_id)
     910          126 :             InitializeSystemUser(MyClientConnectionInfo.authn_id,
     911              :                                  hba_authname(MyClientConnectionInfo.auth_method));
     912        13746 :         am_superuser = superuser();
     913              :     }
     914              : 
     915              :     /* Report any SSL/GSS details for the session. */
     916        18089 :     if (MyProcPort != NULL)
     917              :     {
     918              :         Assert(!bootstrap);
     919              : 
     920        13746 :         pgstat_bestart_security();
     921              :     }
     922              : 
     923              :     /*
     924              :      * Binary upgrades only allowed super-user connections
     925              :      */
     926        18089 :     if (IsBinaryUpgrade && !am_superuser)
     927              :     {
     928            0 :         ereport(FATAL,
     929              :                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
     930              :                  errmsg("must be superuser to connect in binary upgrade mode")));
     931              :     }
     932              : 
     933              :     /*
     934              :      * The last few regular connection slots are reserved for superusers and
     935              :      * roles with privileges of pg_use_reserved_connections.  We do not apply
     936              :      * these limits to background processes, since they all have their own
     937              :      * pools of PGPROC slots.
     938              :      *
     939              :      * Note: At this point, the new backend has already claimed a proc struct,
     940              :      * so we must check whether the number of free slots is strictly less than
     941              :      * the reserved connection limits.
     942              :      */
     943        18089 :     if (AmRegularBackendProcess() && !am_superuser &&
     944          254 :         (SuperuserReservedConnections + ReservedConnections) > 0 &&
     945          254 :         !HaveNFreeProcs(SuperuserReservedConnections + ReservedConnections, &nfree))
     946              :     {
     947            4 :         if (nfree < SuperuserReservedConnections)
     948            1 :             ereport(FATAL,
     949              :                     (errcode(ERRCODE_TOO_MANY_CONNECTIONS),
     950              :                      errmsg("remaining connection slots are reserved for roles with the %s attribute",
     951              :                             "SUPERUSER")));
     952              : 
     953            3 :         if (!has_privs_of_role(GetUserId(), ROLE_PG_USE_RESERVED_CONNECTIONS))
     954            1 :             ereport(FATAL,
     955              :                     (errcode(ERRCODE_TOO_MANY_CONNECTIONS),
     956              :                      errmsg("remaining connection slots are reserved for roles with privileges of the \"%s\" role",
     957              :                             "pg_use_reserved_connections")));
     958              :     }
     959              : 
     960              :     /* Check replication permissions needed for walsender processes. */
     961        18087 :     if (am_walsender)
     962              :     {
     963              :         Assert(!bootstrap);
     964              : 
     965         1213 :         if (!has_rolreplication(GetUserId()))
     966            0 :             ereport(FATAL,
     967              :                     (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
     968              :                      errmsg("permission denied to start WAL sender"),
     969              :                      errdetail("Only roles with the %s attribute may start a WAL sender process.",
     970              :                                "REPLICATION")));
     971              :     }
     972              : 
     973              :     /*
     974              :      * If this is a plain walsender only supporting physical replication, we
     975              :      * don't want to connect to any particular database. Just finish the
     976              :      * backend startup by processing any options from the startup packet, and
     977              :      * we're done.
     978              :      */
     979        18087 :     if (am_walsender && !am_db_walsender)
     980              :     {
     981              :         /* process any options passed in the startup packet */
     982          477 :         if (MyProcPort != NULL)
     983          477 :             process_startup_options(MyProcPort, am_superuser);
     984              : 
     985              :         /* Apply PostAuthDelay as soon as we've read all options */
     986          477 :         if (PostAuthDelay > 0)
     987            0 :             pg_usleep(PostAuthDelay * 1000000L);
     988              : 
     989              :         /* initialize client encoding */
     990          477 :         InitializeClientEncoding();
     991              : 
     992              :         /* fill in the remainder of this entry in the PgBackendStatus array */
     993          477 :         pgstat_bestart_final();
     994              : 
     995              :         /* close the transaction we started above */
     996          477 :         CommitTransactionCommand();
     997              : 
     998              :         /* send any WARNINGs we've accumulated during initialization */
     999          477 :         EmitConnectionWarnings();
    1000              : 
    1001          477 :         return;
    1002              :     }
    1003              : 
    1004              :     /*
    1005              :      * Set up the global variables holding database id and default tablespace.
    1006              :      * But note we won't actually try to touch the database just yet.
    1007              :      *
    1008              :      * We take a shortcut in the bootstrap case, otherwise we have to look up
    1009              :      * the db's entry in pg_database.
    1010              :      */
    1011        17610 :     if (bootstrap)
    1012              :     {
    1013           51 :         dboid = Template1DbOid;
    1014           51 :         MyDatabaseTableSpace = DEFAULTTABLESPACE_OID;
    1015              :     }
    1016        17559 :     else if (in_dbname != NULL)
    1017              :     {
    1018              :         HeapTuple   tuple;
    1019              :         Form_pg_database dbform;
    1020              : 
    1021        13342 :         tuple = GetDatabaseTuple(in_dbname);
    1022        13342 :         if (!HeapTupleIsValid(tuple))
    1023            9 :             ereport(FATAL,
    1024              :                     (errcode(ERRCODE_UNDEFINED_DATABASE),
    1025              :                      errmsg("database \"%s\" does not exist", in_dbname)));
    1026        13333 :         dbform = (Form_pg_database) GETSTRUCT(tuple);
    1027        13333 :         dboid = dbform->oid;
    1028              :     }
    1029         4217 :     else if (!OidIsValid(dboid))
    1030              :     {
    1031              :         /*
    1032              :          * If this is a background worker not bound to any particular
    1033              :          * database, we're done now.  Everything that follows only makes sense
    1034              :          * if we are bound to a specific database.  We do need to close the
    1035              :          * transaction we started before returning.
    1036              :          */
    1037          449 :         if (!bootstrap)
    1038              :         {
    1039          449 :             pgstat_bestart_final();
    1040          449 :             CommitTransactionCommand();
    1041              :         }
    1042          449 :         return;
    1043              :     }
    1044              : 
    1045              :     /*
    1046              :      * Now, take a writer's lock on the database we are trying to connect to.
    1047              :      * If there is a concurrently running DROP DATABASE on that database, this
    1048              :      * will block us until it finishes (and has committed its update of
    1049              :      * pg_database).
    1050              :      *
    1051              :      * Note that the lock is not held long, only until the end of this startup
    1052              :      * transaction.  This is OK since we will advertise our use of the
    1053              :      * database in the ProcArray before dropping the lock (in fact, that's the
    1054              :      * next thing to do).  Anyone trying a DROP DATABASE after this point will
    1055              :      * see us in the array once they have the lock.  Ordering is important for
    1056              :      * this because we don't want to advertise ourselves as being in this
    1057              :      * database until we have the lock; otherwise we create what amounts to a
    1058              :      * deadlock with CountOtherDBBackends().
    1059              :      *
    1060              :      * Note: use of RowExclusiveLock here is reasonable because we envision
    1061              :      * our session as being a concurrent writer of the database.  If we had a
    1062              :      * way of declaring a session as being guaranteed-read-only, we could use
    1063              :      * AccessShareLock for such sessions and thereby not conflict against
    1064              :      * CREATE DATABASE.
    1065              :      */
    1066        17152 :     if (!bootstrap)
    1067        17101 :         LockSharedObject(DatabaseRelationId, dboid, 0, RowExclusiveLock);
    1068              : 
    1069              :     /*
    1070              :      * Recheck pg_database to make sure the target database hasn't gone away.
    1071              :      * If there was a concurrent DROP DATABASE, this ensures we will die
    1072              :      * cleanly without creating a mess.
    1073              :      */
    1074        17152 :     if (!bootstrap)
    1075              :     {
    1076              :         HeapTuple   tuple;
    1077              :         Form_pg_database datform;
    1078              : 
    1079        17101 :         tuple = GetDatabaseTupleByOid(dboid);
    1080        17101 :         if (HeapTupleIsValid(tuple))
    1081        17101 :             datform = (Form_pg_database) GETSTRUCT(tuple);
    1082              : 
    1083        17101 :         if (!HeapTupleIsValid(tuple) ||
    1084        13333 :             (in_dbname && namestrcmp(&datform->datname, in_dbname)))
    1085              :         {
    1086            0 :             if (in_dbname)
    1087            0 :                 ereport(FATAL,
    1088              :                         (errcode(ERRCODE_UNDEFINED_DATABASE),
    1089              :                          errmsg("database \"%s\" does not exist", in_dbname),
    1090              :                          errdetail("It seems to have just been dropped or renamed.")));
    1091              :             else
    1092            0 :                 ereport(FATAL,
    1093              :                         (errcode(ERRCODE_UNDEFINED_DATABASE),
    1094              :                          errmsg("database %u does not exist", dboid)));
    1095              :         }
    1096              : 
    1097        17101 :         strlcpy(dbname, NameStr(datform->datname), sizeof(dbname));
    1098              : 
    1099        17101 :         if (database_is_invalid_form(datform))
    1100              :         {
    1101            5 :             ereport(FATAL,
    1102              :                     errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
    1103              :                     errmsg("cannot connect to invalid database \"%s\"", dbname),
    1104              :                     errhint("Use DROP DATABASE to drop invalid databases."));
    1105              :         }
    1106              : 
    1107        17096 :         MyDatabaseTableSpace = datform->dattablespace;
    1108        17096 :         MyDatabaseHasLoginEventTriggers = datform->dathasloginevt;
    1109              :         /* pass the database name back to the caller */
    1110        17096 :         if (out_dbname)
    1111         1723 :             strcpy(out_dbname, dbname);
    1112              :     }
    1113              : 
    1114              :     /*
    1115              :      * Now that we rechecked, we are certain to be connected to a database and
    1116              :      * thus can set MyDatabaseId.
    1117              :      *
    1118              :      * It is important that MyDatabaseId only be set once we are sure that the
    1119              :      * target database can no longer be concurrently dropped or renamed.  For
    1120              :      * example, without this guarantee, pgstat_update_dbstats() could create
    1121              :      * entries for databases that were just dropped in the pgstat shutdown
    1122              :      * callback, which could confuse other code paths like the autovacuum
    1123              :      * scheduler.
    1124              :      */
    1125        17147 :     MyDatabaseId = dboid;
    1126              : 
    1127              :     /*
    1128              :      * Now we can mark our PGPROC entry with the database ID.
    1129              :      *
    1130              :      * We assume this is an atomic store so no lock is needed; though actually
    1131              :      * things would work fine even if it weren't atomic.  Anyone searching the
    1132              :      * ProcArray for this database's ID should hold the database lock, so they
    1133              :      * would not be executing concurrently with this store.  A process looking
    1134              :      * for another database's ID could in theory see a chance match if it read
    1135              :      * a partially-updated databaseId value; but as long as all such searches
    1136              :      * wait and retry, as in CountOtherDBBackends(), they will certainly see
    1137              :      * the correct value on their next try.
    1138              :      */
    1139        17147 :     MyProc->databaseId = MyDatabaseId;
    1140              : 
    1141              :     /*
    1142              :      * We established a catalog snapshot while reading pg_authid and/or
    1143              :      * pg_database; but until we have set up MyDatabaseId, we won't react to
    1144              :      * incoming sinval messages for unshared catalogs, so we won't realize it
    1145              :      * if the snapshot has been invalidated.  Assume it's no good anymore.
    1146              :      */
    1147        17147 :     InvalidateCatalogSnapshot();
    1148              : 
    1149              :     /*
    1150              :      * Now we should be able to access the database directory safely. Verify
    1151              :      * it's there and looks reasonable.
    1152              :      */
    1153        17147 :     fullpath = GetDatabasePath(MyDatabaseId, MyDatabaseTableSpace);
    1154              : 
    1155        17147 :     if (!bootstrap)
    1156              :     {
    1157        17096 :         if (access(fullpath, F_OK) == -1)
    1158              :         {
    1159            0 :             if (errno == ENOENT)
    1160            0 :                 ereport(FATAL,
    1161              :                         (errcode(ERRCODE_UNDEFINED_DATABASE),
    1162              :                          errmsg("database \"%s\" does not exist",
    1163              :                                 dbname),
    1164              :                          errdetail("The database subdirectory \"%s\" is missing.",
    1165              :                                    fullpath)));
    1166              :             else
    1167            0 :                 ereport(FATAL,
    1168              :                         (errcode_for_file_access(),
    1169              :                          errmsg("could not access directory \"%s\": %m",
    1170              :                                 fullpath)));
    1171              :         }
    1172              : 
    1173        17096 :         ValidatePgVersion(fullpath);
    1174              :     }
    1175              : 
    1176        17147 :     SetDatabasePath(fullpath);
    1177        17147 :     pfree(fullpath);
    1178              : 
    1179              :     /*
    1180              :      * It's now possible to do real access to the system catalogs.
    1181              :      *
    1182              :      * Load relcache entries for the system catalogs.  This must create at
    1183              :      * least the minimum set of "nailed-in" cache entries.
    1184              :      */
    1185        17147 :     RelationCacheInitializePhase3();
    1186              : 
    1187              :     /* set up ACL framework (so CheckMyDatabase can check permissions) */
    1188        17145 :     initialize_acl();
    1189              : 
    1190              :     /*
    1191              :      * Re-read the pg_database row for our database, check permissions and set
    1192              :      * up database-specific GUC settings.  We can't do this until all the
    1193              :      * database-access infrastructure is up.  (Also, it wants to know if the
    1194              :      * user is a superuser, so the above stuff has to happen first.)
    1195              :      */
    1196        17145 :     if (!bootstrap)
    1197        17094 :         CheckMyDatabase(dbname, am_superuser,
    1198        17094 :                         (flags & INIT_PG_OVERRIDE_ALLOW_CONNS) != 0);
    1199              : 
    1200              :     /*
    1201              :      * Now process any command-line switches and any additional GUC variable
    1202              :      * settings passed in the startup packet.   We couldn't do this before
    1203              :      * because we didn't know if client is a superuser.
    1204              :      */
    1205        17142 :     if (MyProcPort != NULL)
    1206        13253 :         process_startup_options(MyProcPort, am_superuser);
    1207              : 
    1208              :     /* Process pg_db_role_setting options */
    1209        17142 :     process_settings(MyDatabaseId, GetSessionUserId());
    1210              : 
    1211              :     /* Apply PostAuthDelay as soon as we've read all options */
    1212        17142 :     if (PostAuthDelay > 0)
    1213            0 :         pg_usleep(PostAuthDelay * 1000000L);
    1214              : 
    1215              :     /*
    1216              :      * Initialize various default states that can't be set up until we've
    1217              :      * selected the active user and gotten the right GUC settings.
    1218              :      */
    1219              : 
    1220              :     /* set default namespace search path */
    1221        17142 :     InitializeSearchPath();
    1222              : 
    1223              :     /* initialize client encoding */
    1224        17142 :     InitializeClientEncoding();
    1225              : 
    1226              :     /* Initialize this backend's session state. */
    1227        17142 :     InitializeSession();
    1228              : 
    1229              :     /*
    1230              :      * If this is an interactive session, load any libraries that should be
    1231              :      * preloaded at backend start.  Since those are determined by GUCs, this
    1232              :      * can't happen until GUC settings are complete, but we want it to happen
    1233              :      * during the initial transaction in case anything that requires database
    1234              :      * access needs to be done.
    1235              :      */
    1236        17142 :     if ((flags & INIT_PG_LOAD_SESSION_LIBS) != 0)
    1237        12585 :         process_session_preload_libraries();
    1238              : 
    1239              :     /* fill in the remainder of this entry in the PgBackendStatus array */
    1240        17142 :     if (!bootstrap)
    1241        17091 :         pgstat_bestart_final();
    1242              : 
    1243              :     /* close the transaction we started above */
    1244        17142 :     if (!bootstrap)
    1245        17091 :         CommitTransactionCommand();
    1246              : 
    1247              :     /* send any WARNINGs we've accumulated during initialization */
    1248        17142 :     EmitConnectionWarnings();
    1249              : }
    1250              : 
    1251              : /*
    1252              :  * Process any command-line switches and any additional GUC variable
    1253              :  * settings passed in the startup packet.
    1254              :  */
    1255              : static void
    1256        13730 : process_startup_options(Port *port, bool am_superuser)
    1257              : {
    1258              :     GucContext  gucctx;
    1259              :     ListCell   *gucopts;
    1260              : 
    1261        13730 :     gucctx = am_superuser ? PGC_SU_BACKEND : PGC_BACKEND;
    1262              : 
    1263              :     /*
    1264              :      * First process any command-line switches that were included in the
    1265              :      * startup packet, if we are in a regular backend.
    1266              :      */
    1267        13730 :     if (port->cmdline_options != NULL)
    1268              :     {
    1269              :         /*
    1270              :          * The maximum possible number of commandline arguments that could
    1271              :          * come from port->cmdline_options is (strlen + 1) / 2; see
    1272              :          * pg_split_opts().
    1273              :          */
    1274              :         char      **av;
    1275              :         int         maxac;
    1276              :         int         ac;
    1277              : 
    1278         3875 :         maxac = 2 + (strlen(port->cmdline_options) + 1) / 2;
    1279              : 
    1280         3875 :         av = palloc_array(char *, maxac);
    1281         3875 :         ac = 0;
    1282              : 
    1283         3875 :         av[ac++] = "postgres";
    1284              : 
    1285         3875 :         pg_split_opts(av, &ac, port->cmdline_options);
    1286              : 
    1287         3875 :         av[ac] = NULL;
    1288              : 
    1289              :         Assert(ac < maxac);
    1290              : 
    1291         3875 :         (void) process_postgres_switches(ac, av, gucctx, NULL);
    1292              :     }
    1293              : 
    1294              :     /*
    1295              :      * Process any additional GUC variable settings passed in startup packet.
    1296              :      * These are handled exactly like command-line variables.
    1297              :      */
    1298        13730 :     gucopts = list_head(port->guc_options);
    1299        32872 :     while (gucopts)
    1300              :     {
    1301              :         char       *name;
    1302              :         char       *value;
    1303              : 
    1304        19142 :         name = lfirst(gucopts);
    1305        19142 :         gucopts = lnext(port->guc_options, gucopts);
    1306              : 
    1307        19142 :         value = lfirst(gucopts);
    1308        19142 :         gucopts = lnext(port->guc_options, gucopts);
    1309              : 
    1310        19142 :         SetConfigOption(name, value, gucctx, PGC_S_CLIENT);
    1311              :     }
    1312        13730 : }
    1313              : 
    1314              : /*
    1315              :  * Load GUC settings from pg_db_role_setting.
    1316              :  *
    1317              :  * We try specific settings for the database/role combination, as well as
    1318              :  * general for this database and for this user.
    1319              :  */
    1320              : static void
    1321        17142 : process_settings(Oid databaseid, Oid roleid)
    1322              : {
    1323              :     Relation    relsetting;
    1324              :     Snapshot    snapshot;
    1325              : 
    1326        17142 :     if (!IsUnderPostmaster)
    1327          119 :         return;
    1328              : 
    1329        17023 :     relsetting = table_open(DbRoleSettingRelationId, AccessShareLock);
    1330              : 
    1331              :     /* read all the settings under the same snapshot for efficiency */
    1332        17023 :     snapshot = RegisterSnapshot(GetCatalogSnapshot(DbRoleSettingRelationId));
    1333              : 
    1334              :     /* Later settings are ignored if set earlier. */
    1335        17023 :     ApplySetting(snapshot, databaseid, roleid, relsetting, PGC_S_DATABASE_USER);
    1336        17023 :     ApplySetting(snapshot, InvalidOid, roleid, relsetting, PGC_S_USER);
    1337        17023 :     ApplySetting(snapshot, databaseid, InvalidOid, relsetting, PGC_S_DATABASE);
    1338        17023 :     ApplySetting(snapshot, InvalidOid, InvalidOid, relsetting, PGC_S_GLOBAL);
    1339              : 
    1340        17023 :     UnregisterSnapshot(snapshot);
    1341        17023 :     table_close(relsetting, AccessShareLock);
    1342              : }
    1343              : 
    1344              : /*
    1345              :  * Backend-shutdown callback.  Do cleanup that we want to be sure happens
    1346              :  * before all the supporting modules begin to nail their doors shut via
    1347              :  * their own callbacks.
    1348              :  *
    1349              :  * User-level cleanup, such as temp-relation removal and UNLISTEN, happens
    1350              :  * via separate callbacks that execute before this one.  We don't combine the
    1351              :  * callbacks because we still want this one to happen if the user-level
    1352              :  * cleanup fails.
    1353              :  */
    1354              : static void
    1355        18578 : ShutdownPostgres(int code, Datum arg)
    1356              : {
    1357              :     /* Make sure we've killed any active transaction */
    1358        18578 :     AbortOutOfAnyTransaction();
    1359              : 
    1360              :     /*
    1361              :      * User locks are not released by transaction end, so be sure to release
    1362              :      * them explicitly.
    1363              :      */
    1364        18578 :     LockReleaseAll(USER_LOCKMETHOD, true);
    1365        18578 : }
    1366              : 
    1367              : 
    1368              : /*
    1369              :  * STATEMENT_TIMEOUT handler: trigger a query-cancel interrupt.
    1370              :  */
    1371              : static void
    1372            6 : StatementTimeoutHandler(void)
    1373              : {
    1374            6 :     int         sig = SIGINT;
    1375              : 
    1376              :     /*
    1377              :      * During authentication the timeout is used to deal with
    1378              :      * authentication_timeout - we want to quit in response to such timeouts.
    1379              :      */
    1380            6 :     if (ClientAuthInProgress)
    1381            0 :         sig = SIGTERM;
    1382              : 
    1383              : #ifdef HAVE_SETSID
    1384              :     /* try to signal whole process group */
    1385            6 :     kill(-MyProcPid, sig);
    1386              : #endif
    1387            6 :     kill(MyProcPid, sig);
    1388            6 : }
    1389              : 
    1390              : /*
    1391              :  * LOCK_TIMEOUT handler: trigger a query-cancel interrupt.
    1392              :  */
    1393              : static void
    1394            4 : LockTimeoutHandler(void)
    1395              : {
    1396              : #ifdef HAVE_SETSID
    1397              :     /* try to signal whole process group */
    1398            4 :     kill(-MyProcPid, SIGINT);
    1399              : #endif
    1400            4 :     kill(MyProcPid, SIGINT);
    1401            4 : }
    1402              : 
    1403              : static void
    1404            1 : TransactionTimeoutHandler(void)
    1405              : {
    1406            1 :     TransactionTimeoutPending = true;
    1407            1 :     InterruptPending = true;
    1408            1 :     SetLatch(MyLatch);
    1409            1 : }
    1410              : 
    1411              : static void
    1412            1 : IdleInTransactionSessionTimeoutHandler(void)
    1413              : {
    1414            1 :     IdleInTransactionSessionTimeoutPending = true;
    1415            1 :     InterruptPending = true;
    1416            1 :     SetLatch(MyLatch);
    1417            1 : }
    1418              : 
    1419              : static void
    1420            1 : IdleSessionTimeoutHandler(void)
    1421              : {
    1422            1 :     IdleSessionTimeoutPending = true;
    1423            1 :     InterruptPending = true;
    1424            1 :     SetLatch(MyLatch);
    1425            1 : }
    1426              : 
    1427              : static void
    1428            9 : IdleStatsUpdateTimeoutHandler(void)
    1429              : {
    1430            9 :     IdleStatsUpdateTimeoutPending = true;
    1431            9 :     InterruptPending = true;
    1432            9 :     SetLatch(MyLatch);
    1433            9 : }
    1434              : 
    1435              : static void
    1436            0 : ClientCheckTimeoutHandler(void)
    1437              : {
    1438            0 :     CheckClientConnectionPending = true;
    1439            0 :     InterruptPending = true;
    1440            0 :     SetLatch(MyLatch);
    1441            0 : }
    1442              : 
    1443              : /*
    1444              :  * Returns true if at least one role is defined in this database cluster.
    1445              :  */
    1446              : static bool
    1447           70 : ThereIsAtLeastOneRole(void)
    1448              : {
    1449              :     Relation    pg_authid_rel;
    1450              :     TableScanDesc scan;
    1451              :     bool        result;
    1452              : 
    1453           70 :     pg_authid_rel = table_open(AuthIdRelationId, AccessShareLock);
    1454              : 
    1455           70 :     scan = table_beginscan_catalog(pg_authid_rel, 0, NULL);
    1456           70 :     result = (heap_getnext(scan, ForwardScanDirection) != NULL);
    1457              : 
    1458           70 :     table_endscan(scan);
    1459           70 :     table_close(pg_authid_rel, AccessShareLock);
    1460              : 
    1461           70 :     return result;
    1462              : }
    1463              : 
    1464              : /*
    1465              :  * Stores a warning message to be sent later via EmitConnectionWarnings().
    1466              :  * Both msg and detail must be non-NULL.
    1467              :  *
    1468              :  * NB: Caller should ensure the strings are allocated in a long-lived context
    1469              :  * like TopMemoryContext.
    1470              :  */
    1471              : void
    1472            1 : StoreConnectionWarning(char *msg, char *detail)
    1473              : {
    1474              :     MemoryContext oldcontext;
    1475              : 
    1476              :     Assert(msg);
    1477              :     Assert(detail);
    1478              : 
    1479            1 :     if (ConnectionWarningsEmitted)
    1480            0 :         elog(ERROR, "StoreConnectionWarning() called after EmitConnectionWarnings()");
    1481              : 
    1482            1 :     oldcontext = MemoryContextSwitchTo(TopMemoryContext);
    1483              : 
    1484            1 :     ConnectionWarningMessages = lappend(ConnectionWarningMessages, msg);
    1485            1 :     ConnectionWarningDetails = lappend(ConnectionWarningDetails, detail);
    1486              : 
    1487            1 :     MemoryContextSwitchTo(oldcontext);
    1488            1 : }
    1489              : 
    1490              : /*
    1491              :  * Sends the warning messages saved via StoreConnectionWarning() and frees the
    1492              :  * strings and lists.
    1493              :  *
    1494              :  * NB: This can only be called once per backend.
    1495              :  */
    1496              : static void
    1497        17619 : EmitConnectionWarnings(void)
    1498              : {
    1499              :     ListCell   *lc_msg;
    1500              :     ListCell   *lc_detail;
    1501              : 
    1502        17619 :     if (ConnectionWarningsEmitted)
    1503            0 :         elog(ERROR, "EmitConnectionWarnings() called more than once");
    1504              :     else
    1505        17619 :         ConnectionWarningsEmitted = true;
    1506              : 
    1507        17620 :     forboth(lc_msg, ConnectionWarningMessages,
    1508              :             lc_detail, ConnectionWarningDetails)
    1509              :     {
    1510            1 :         ereport(WARNING,
    1511              :                 (errmsg("%s", (char *) lfirst(lc_msg)),
    1512              :                  errdetail("%s", (char *) lfirst(lc_detail))));
    1513              :     }
    1514              : 
    1515        17619 :     list_free_deep(ConnectionWarningMessages);
    1516        17619 :     list_free_deep(ConnectionWarningDetails);
    1517        17619 : }
        

Generated by: LCOV version 2.0-1