tcopprot.h File Reference

#include "nodes/params.h"
#include "nodes/plannodes.h"
#include "storage/procsignal.h"
#include "utils/guc.h"
#include "utils/queryenvironment.h"

Include dependency graph for tcopprot.h:

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Go to the source code of this file.

Macros
#define	STACK_DEPTH_SLOP   (512 * 1024L)
#define	RESTRICT_RELKIND_VIEW   0x01
#define	RESTRICT_RELKIND_FOREIGN_TABLE   0x02

Enumerations
enum	LogStmtLevel { LOGSTMT_NONE , LOGSTMT_DDL , LOGSTMT_MOD , LOGSTMT_ALL }

Functions
List *	pg_parse_query (const char *query_string)
List *	pg_rewrite_query (Query *query)
List *	pg_analyze_and_rewrite_fixedparams (RawStmt *parsetree, const char *query_string, const Oid *paramTypes, int numParams, QueryEnvironment *queryEnv)
List *	pg_analyze_and_rewrite_varparams (RawStmt *parsetree, const char *query_string, Oid **paramTypes, int *numParams, QueryEnvironment *queryEnv)
List *	pg_analyze_and_rewrite_withcb (RawStmt *parsetree, const char *query_string, ParserSetupHook parserSetup, void *parserSetupArg, QueryEnvironment *queryEnv)
PlannedStmt *	pg_plan_query (Query *querytree, const char *query_string, int cursorOptions, ParamListInfo boundParams)
List *	pg_plan_queries (List *querytrees, const char *query_string, int cursorOptions, ParamListInfo boundParams)
void	die (SIGNAL_ARGS)
void	quickdie (SIGNAL_ARGS) pg_attribute_noreturn()
void	StatementCancelHandler (SIGNAL_ARGS)
void	FloatExceptionHandler (SIGNAL_ARGS) pg_attribute_noreturn()
void	HandleRecoveryConflictInterrupt (ProcSignalReason reason)
void	ProcessClientReadInterrupt (bool blocked)
void	ProcessClientWriteInterrupt (bool blocked)
void	process_postgres_switches (int argc, char *argv[], GucContext ctx, const char **dbname)
void	PostgresSingleUserMain (int argc, char *argv[], const char *username) pg_attribute_noreturn()
void	PostgresMain (const char *dbname, const char *username) pg_attribute_noreturn()
long	get_stack_depth_rlimit (void)
void	ResetUsage (void)
void	ShowUsage (const char *title)
int	check_log_duration (char *msec_str, bool was_logged)
void	set_debug_options (int debug_flag, GucContext context, GucSource source)
bool	set_plan_disabling_options (const char *arg, GucContext context, GucSource source)
const char *	get_stats_option_name (const char *arg)

Variables
PGDLLIMPORT CommandDest	whereToSendOutput
PGDLLIMPORT const char *	debug_query_string
PGDLLIMPORT int	max_stack_depth
PGDLLIMPORT int	PostAuthDelay
PGDLLIMPORT int	client_connection_check_interval
PGDLLIMPORT bool	Log_disconnections
PGDLLIMPORT int	log_statement
PGDLLIMPORT int	restrict_nonsystem_relation_kind

Macro Definition Documentation

RESTRICT_RELKIND_FOREIGN_TABLE

#define RESTRICT_RELKIND_FOREIGN_TABLE   0x02

Definition at line 48 of file tcopprot.h.

RESTRICT_RELKIND_VIEW

#define RESTRICT_RELKIND_VIEW   0x01

Definition at line 47 of file tcopprot.h.

STACK_DEPTH_SLOP

#define STACK_DEPTH_SLOP   (512 * 1024L)

Definition at line 25 of file tcopprot.h.

Enumeration Type Documentation

LogStmtLevel

enum LogStmtLevel

Enumerator
LOGSTMT_NONE
LOGSTMT_DDL
LOGSTMT_MOD
LOGSTMT_ALL

Definition at line 35 of file tcopprot.h.

{
    LOGSTMT_NONE,               /* log no statements */
    LOGSTMT_DDL,                /* log data definition statements */
    LOGSTMT_MOD,                /* log modification statements, plus DDL */
    LOGSTMT_ALL,                /* log all statements */
} LogStmtLevel;

Function Documentation

check_log_duration()

int check_log_duration	(	char *	msec_str,
		bool	was_logged
	)

Definition at line 2412 of file postgres.c.

{
    if (log_duration || log_min_duration_sample >= 0 ||
        log_min_duration_statement >= 0 || xact_is_sampled)
    {
        long        secs;
        int         usecs;
        int         msecs;
        bool        exceeded_duration;
        bool        exceeded_sample_duration;
        bool        in_sample = false;
 
        TimestampDifference(GetCurrentStatementStartTimestamp(),
                            GetCurrentTimestamp(),
                            &secs, &usecs);
        msecs = usecs / 1000;
 
        /*
         * This odd-looking test for log_min_duration_* being exceeded is
         * designed to avoid integer overflow with very long durations: don't
         * compute secs * 1000 until we've verified it will fit in int.
         */
        exceeded_duration = (log_min_duration_statement == 0 ||
                             (log_min_duration_statement > 0 &&
                              (secs > log_min_duration_statement / 1000 ||
                               secs * 1000 + msecs >= log_min_duration_statement)));
 
        exceeded_sample_duration = (log_min_duration_sample == 0 ||
                                    (log_min_duration_sample > 0 &&
                                     (secs > log_min_duration_sample / 1000 ||
                                      secs * 1000 + msecs >= log_min_duration_sample)));
 
        /*
         * Do not log if log_statement_sample_rate = 0. Log a sample if
         * log_statement_sample_rate <= 1 and avoid unnecessary PRNG call if
         * log_statement_sample_rate = 1.
         */
        if (exceeded_sample_duration)
            in_sample = log_statement_sample_rate != 0 &&
                (log_statement_sample_rate == 1 ||
                 pg_prng_double(&pg_global_prng_state) <= log_statement_sample_rate);
 
        if (exceeded_duration || in_sample || log_duration || xact_is_sampled)
        {
            snprintf(msec_str, 32, "%ld.%03d",
                     secs * 1000 + msecs, usecs % 1000);
            if ((exceeded_duration || in_sample || xact_is_sampled) && !was_logged)
                return 2;
            else
                return 1;
        }
    }
 
    return 0;
}

References GetCurrentStatementStartTimestamp(), GetCurrentTimestamp(), log_duration, log_min_duration_sample, log_min_duration_statement, log_statement_sample_rate, pg_global_prng_state, pg_prng_double(), snprintf, TimestampDifference(), and xact_is_sampled.

Referenced by exec_bind_message(), exec_execute_message(), exec_parse_message(), exec_simple_query(), and HandleFunctionRequest().

die()

void die

(

SIGNAL_ARGS

)

Definition at line 3015 of file postgres.c.

{
    /* Don't joggle the elbow of proc_exit */
    if (!proc_exit_inprogress)
    {
        InterruptPending = true;
        ProcDiePending = true;
    }
 
    /* for the cumulative stats system */
    pgStatSessionEndCause = DISCONNECT_KILLED;
 
    /* If we're still here, waken anything waiting on the process latch */
    SetLatch(MyLatch);
 
    /*
     * If we're in single user mode, we want to quit immediately - we can't
     * rely on latches as they wouldn't work when stdin/stdout is a file.
     * Rather ugly, but it's unlikely to be worthwhile to invest much more
     * effort just for the benefit of single user mode.
     */
    if (DoingCommandRead && whereToSendOutput != DestRemote)
        ProcessInterrupts();
}

References DestRemote, DISCONNECT_KILLED, DoingCommandRead, InterruptPending, MyLatch, pgStatSessionEndCause, proc_exit_inprogress, ProcDiePending, ProcessInterrupts(), SetLatch(), and whereToSendOutput.

Referenced by PostgresMain().

FloatExceptionHandler()

void FloatExceptionHandler

(

SIGNAL_ARGS

)

Definition at line 3062 of file postgres.c.

{
    /* We're not returning, so no need to save errno */
    ereport(ERROR,
            (errcode(ERRCODE_FLOATING_POINT_EXCEPTION),
             errmsg("floating-point exception"),
             errdetail("An invalid floating-point operation was signaled. "
                       "This probably means an out-of-range result or an "
                       "invalid operation, such as division by zero.")));
}

References ereport, errcode(), errdetail(), errmsg(), and ERROR.

Referenced by AutoVacWorkerMain(), BackgroundWorkerMain(), plperl_init_interp(), PostgresMain(), and ReplSlotSyncWorkerMain().

get_stack_depth_rlimit()

long get_stack_depth_rlimit

(

void

)

Definition at line 5097 of file postgres.c.

{
#if defined(HAVE_GETRLIMIT)
    static long val = 0;
 
    /* This won't change after process launch, so check just once */
    if (val == 0)
    {
        struct rlimit rlim;
 
        if (getrlimit(RLIMIT_STACK, &rlim) < 0)
            val = -1;
        else if (rlim.rlim_cur == RLIM_INFINITY)
            val = LONG_MAX;
        /* rlim_cur is probably of an unsigned type, so check for overflow */
        else if (rlim.rlim_cur >= LONG_MAX)
            val = LONG_MAX;
        else
            val = rlim.rlim_cur;
    }
    return val;
#else
    /* On Windows we set the backend stack size in src/backend/Makefile */
    return WIN32_STACK_RLIMIT;
#endif
}

References val.

Referenced by check_max_stack_depth(), and InitializeGUCOptionsFromEnvironment().

get_stats_option_name()

const char* get_stats_option_name

(

const char *

arg

)

Definition at line 3853 of file postgres.c.

{
    switch (arg[0])
    {
        case 'p':
            if (optarg[1] == 'a')   /* "parser" */
                return "log_parser_stats";
            else if (optarg[1] == 'l')  /* "planner" */
                return "log_planner_stats";
            break;
 
        case 'e':               /* "executor" */
            return "log_executor_stats";
            break;
    }
 
    return NULL;
}

References arg, and optarg.

Referenced by PostmasterMain(), and process_postgres_switches().

HandleRecoveryConflictInterrupt()

void HandleRecoveryConflictInterrupt

(

ProcSignalReason

reason

)

Definition at line 3078 of file postgres.c.

{
    RecoveryConflictPendingReasons[reason] = true;
    RecoveryConflictPending = true;
    InterruptPending = true;
    /* latch will be set by procsignal_sigusr1_handler */
}

References InterruptPending, RecoveryConflictPending, and RecoveryConflictPendingReasons.

Referenced by procsignal_sigusr1_handler().

pg_analyze_and_rewrite_fixedparams()

List* pg_analyze_and_rewrite_fixedparams	(	RawStmt *	parsetree,
		const char *	query_string,
		const Oid *	paramTypes,
		int	numParams,
		QueryEnvironment *	queryEnv
	)

Definition at line 676 of file postgres.c.

{
    Query      *query;
    List       *querytree_list;
 
    TRACE_POSTGRESQL_QUERY_REWRITE_START(query_string);
 
    /*
     * (1) Perform parse analysis.
     */
    if (log_parser_stats)
        ResetUsage();
 
    query = parse_analyze_fixedparams(parsetree, query_string, paramTypes, numParams,
                                      queryEnv);
 
    if (log_parser_stats)
        ShowUsage("PARSE ANALYSIS STATISTICS");
 
    /*
     * (2) Rewrite the queries, as necessary
     */
    querytree_list = pg_rewrite_query(query);
 
    TRACE_POSTGRESQL_QUERY_REWRITE_DONE(query_string);
 
    return querytree_list;
}

References log_parser_stats, parse_analyze_fixedparams(), pg_rewrite_query(), ResetUsage(), and ShowUsage().

Referenced by _SPI_execute_plan(), _SPI_prepare_plan(), BeginCopyTo(), exec_simple_query(), execute_sql_string(), and RevalidateCachedQuery().

pg_analyze_and_rewrite_varparams()

List* pg_analyze_and_rewrite_varparams	(	RawStmt *	parsetree,
		const char *	query_string,
		Oid **	paramTypes,
		int *	numParams,
		QueryEnvironment *	queryEnv
	)

Definition at line 715 of file postgres.c.

{
    Query      *query;
    List       *querytree_list;
 
    TRACE_POSTGRESQL_QUERY_REWRITE_START(query_string);
 
    /*
     * (1) Perform parse analysis.
     */
    if (log_parser_stats)
        ResetUsage();
 
    query = parse_analyze_varparams(parsetree, query_string, paramTypes, numParams,
                                    queryEnv);
 
    /*
     * Check all parameter types got determined.
     */
    for (int i = 0; i < *numParams; i++)
    {
        Oid         ptype = (*paramTypes)[i];
 
        if (ptype == InvalidOid || ptype == UNKNOWNOID)
            ereport(ERROR,
                    (errcode(ERRCODE_INDETERMINATE_DATATYPE),
                     errmsg("could not determine data type of parameter $%d",
                            i + 1)));
    }
 
    if (log_parser_stats)
        ShowUsage("PARSE ANALYSIS STATISTICS");
 
    /*
     * (2) Rewrite the queries, as necessary
     */
    querytree_list = pg_rewrite_query(query);
 
    TRACE_POSTGRESQL_QUERY_REWRITE_DONE(query_string);
 
    return querytree_list;
}

References ereport, errcode(), errmsg(), ERROR, i, InvalidOid, log_parser_stats, parse_analyze_varparams(), pg_rewrite_query(), ResetUsage(), and ShowUsage().

Referenced by exec_parse_message(), and PrepareQuery().

pg_analyze_and_rewrite_withcb()

List* pg_analyze_and_rewrite_withcb	(	RawStmt *	parsetree,
		const char *	query_string,
		ParserSetupHook	parserSetup,
		void *	parserSetupArg,
		QueryEnvironment *	queryEnv
	)

Definition at line 769 of file postgres.c.

{
    Query      *query;
    List       *querytree_list;
 
    TRACE_POSTGRESQL_QUERY_REWRITE_START(query_string);
 
    /*
     * (1) Perform parse analysis.
     */
    if (log_parser_stats)
        ResetUsage();
 
    query = parse_analyze_withcb(parsetree, query_string, parserSetup, parserSetupArg,
                                 queryEnv);
 
    if (log_parser_stats)
        ShowUsage("PARSE ANALYSIS STATISTICS");
 
    /*
     * (2) Rewrite the queries, as necessary
     */
    querytree_list = pg_rewrite_query(query);
 
    TRACE_POSTGRESQL_QUERY_REWRITE_DONE(query_string);
 
    return querytree_list;
}

References log_parser_stats, parse_analyze_withcb(), pg_rewrite_query(), ResetUsage(), and ShowUsage().

Referenced by _SPI_execute_plan(), _SPI_prepare_plan(), fmgr_sql_validator(), init_sql_fcache(), inline_set_returning_function(), and RevalidateCachedQuery().

pg_parse_query()

List* pg_parse_query

(

const char *

query_string

)

Definition at line 614 of file postgres.c.

{
    List       *raw_parsetree_list;
 
    TRACE_POSTGRESQL_QUERY_PARSE_START(query_string);
 
    if (log_parser_stats)
        ResetUsage();
 
    raw_parsetree_list = raw_parser(query_string, RAW_PARSE_DEFAULT);
 
    if (log_parser_stats)
        ShowUsage("PARSER STATISTICS");
 
#ifdef DEBUG_NODE_TESTS_ENABLED
 
    /* Optional debugging check: pass raw parsetrees through copyObject() */
    if (Debug_copy_parse_plan_trees)
    {
        List       *new_list = copyObject(raw_parsetree_list);
 
        /* This checks both copyObject() and the equal() routines... */
        if (!equal(new_list, raw_parsetree_list))
            elog(WARNING, "copyObject() failed to produce an equal raw parse tree");
        else
            raw_parsetree_list = new_list;
    }
 
    /*
     * Optional debugging check: pass raw parsetrees through
     * outfuncs/readfuncs
     */
    if (Debug_write_read_parse_plan_trees)
    {
        char       *str = nodeToStringWithLocations(raw_parsetree_list);
        List       *new_list = stringToNodeWithLocations(str);
 
        pfree(str);
        /* This checks both outfuncs/readfuncs and the equal() routines... */
        if (!equal(new_list, raw_parsetree_list))
            elog(WARNING, "outfuncs/readfuncs failed to produce an equal raw parse tree");
        else
            raw_parsetree_list = new_list;
    }
 
#endif                          /* DEBUG_NODE_TESTS_ENABLED */
 
    TRACE_POSTGRESQL_QUERY_PARSE_DONE(query_string);
 
    return raw_parsetree_list;
}

References copyObject, elog, equal(), log_parser_stats, new_list(), nodeToStringWithLocations(), pfree(), RAW_PARSE_DEFAULT, raw_parser(), ResetUsage(), ShowUsage(), str, and WARNING.

Referenced by exec_parse_message(), exec_simple_query(), execute_sql_string(), fmgr_sql_validator(), ImportForeignSchema(), init_sql_fcache(), inline_function(), and inline_set_returning_function().

pg_plan_queries()

List* pg_plan_queries	(	List *	querytrees,
		const char *	query_string,
		int	cursorOptions,
		ParamListInfo	boundParams
	)

Definition at line 981 of file postgres.c.

{
    List       *stmt_list = NIL;
    ListCell   *query_list;
 
    foreach(query_list, querytrees)
    {
        Query      *query = lfirst_node(Query, query_list);
        PlannedStmt *stmt;
 
        if (query->commandType == CMD_UTILITY)
        {
            /* Utility commands require no planning. */
            stmt = makeNode(PlannedStmt);
            stmt->commandType = CMD_UTILITY;
            stmt->canSetTag = query->canSetTag;
            stmt->utilityStmt = query->utilityStmt;
            stmt->stmt_location = query->stmt_location;
            stmt->stmt_len = query->stmt_len;
            stmt->queryId = query->queryId;
        }
        else
        {
            stmt = pg_plan_query(query, query_string, cursorOptions,
                                 boundParams);
        }
 
        stmt_list = lappend(stmt_list, stmt);
    }
 
    return stmt_list;
}

References CMD_UTILITY, Query::commandType, lappend(), lfirst_node, makeNode, NIL, pg_plan_query(), stmt, Query::stmt_location, and Query::utilityStmt.

Referenced by BuildCachedPlan(), exec_simple_query(), and execute_sql_string().

pg_plan_query()

PlannedStmt* pg_plan_query	(	Query *	querytree,
		const char *	query_string,
		int	cursorOptions,
		ParamListInfo	boundParams
	)

Definition at line 893 of file postgres.c.

{
    PlannedStmt *plan;
 
    /* Utility commands have no plans. */
    if (querytree->commandType == CMD_UTILITY)
        return NULL;
 
    /* Planner must have a snapshot in case it calls user-defined functions. */
    Assert(ActiveSnapshotSet());
 
    TRACE_POSTGRESQL_QUERY_PLAN_START();
 
    if (log_planner_stats)
        ResetUsage();
 
    /* call the optimizer */
    plan = planner(querytree, query_string, cursorOptions, boundParams);
 
    if (log_planner_stats)
        ShowUsage("PLANNER STATISTICS");
 
#ifdef DEBUG_NODE_TESTS_ENABLED
 
    /* Optional debugging check: pass plan tree through copyObject() */
    if (Debug_copy_parse_plan_trees)
    {
        PlannedStmt *new_plan = copyObject(plan);
 
        /*
         * equal() currently does not have routines to compare Plan nodes, so
         * don't try to test equality here.  Perhaps fix someday?
         */
#ifdef NOT_USED
        /* This checks both copyObject() and the equal() routines... */
        if (!equal(new_plan, plan))
            elog(WARNING, "copyObject() failed to produce an equal plan tree");
        else
#endif
            plan = new_plan;
    }
 
    /* Optional debugging check: pass plan tree through outfuncs/readfuncs */
    if (Debug_write_read_parse_plan_trees)
    {
        char       *str;
        PlannedStmt *new_plan;
 
        str = nodeToStringWithLocations(plan);
        new_plan = stringToNodeWithLocations(str);
        pfree(str);
 
        /*
         * equal() currently does not have routines to compare Plan nodes, so
         * don't try to test equality here.  Perhaps fix someday?
         */
#ifdef NOT_USED
        /* This checks both outfuncs/readfuncs and the equal() routines... */
        if (!equal(new_plan, plan))
            elog(WARNING, "outfuncs/readfuncs failed to produce an equal plan tree");
        else
#endif
            plan = new_plan;
    }
 
#endif                          /* DEBUG_NODE_TESTS_ENABLED */
 
    /*
     * Print plan if debugging.
     */
    if (Debug_print_plan)
        elog_node_display(LOG, "plan", plan, Debug_pretty_print);
 
    TRACE_POSTGRESQL_QUERY_PLAN_DONE();
 
    return plan;
}

References ActiveSnapshotSet(), Assert, CMD_UTILITY, copyObject, Debug_pretty_print, Debug_print_plan, elog, elog_node_display(), equal(), LOG, log_planner_stats, nodeToStringWithLocations(), pfree(), plan, planner(), querytree(), ResetUsage(), ShowUsage(), str, and WARNING.

Referenced by BeginCopyTo(), ExecCreateTableAs(), init_execution_state(), PerformCursorOpen(), pg_plan_queries(), refresh_matview_datafill(), and standard_ExplainOneQuery().

pg_rewrite_query()

List* pg_rewrite_query

(

Query *

query

)

Definition at line 809 of file postgres.c.

{
    List       *querytree_list;
 
    if (Debug_print_parse)
        elog_node_display(LOG, "parse tree", query,
                          Debug_pretty_print);
 
    if (log_parser_stats)
        ResetUsage();
 
    if (query->commandType == CMD_UTILITY)
    {
        /* don't rewrite utilities, just dump 'em into result list */
        querytree_list = list_make1(query);
    }
    else
    {
        /* rewrite regular queries */
        querytree_list = QueryRewrite(query);
    }
 
    if (log_parser_stats)
        ShowUsage("REWRITER STATISTICS");
 
#ifdef DEBUG_NODE_TESTS_ENABLED
 
    /* Optional debugging check: pass querytree through copyObject() */
    if (Debug_copy_parse_plan_trees)
    {
        List       *new_list;
 
        new_list = copyObject(querytree_list);
        /* This checks both copyObject() and the equal() routines... */
        if (!equal(new_list, querytree_list))
            elog(WARNING, "copyObject() failed to produce an equal rewritten parse tree");
        else
            querytree_list = new_list;
    }
 
    /* Optional debugging check: pass querytree through outfuncs/readfuncs */
    if (Debug_write_read_parse_plan_trees)
    {
        List       *new_list = NIL;
        ListCell   *lc;
 
        foreach(lc, querytree_list)
        {
            Query      *curr_query = lfirst_node(Query, lc);
            char       *str = nodeToStringWithLocations(curr_query);
            Query      *new_query = stringToNodeWithLocations(str);
 
            /*
             * queryId is not saved in stored rules, but we must preserve it
             * here to avoid breaking pg_stat_statements.
             */
            new_query->queryId = curr_query->queryId;
 
            new_list = lappend(new_list, new_query);
            pfree(str);
        }
 
        /* This checks both outfuncs/readfuncs and the equal() routines... */
        if (!equal(new_list, querytree_list))
            elog(WARNING, "outfuncs/readfuncs failed to produce an equal rewritten parse tree");
        else
            querytree_list = new_list;
    }
 
#endif                          /* DEBUG_NODE_TESTS_ENABLED */
 
    if (Debug_print_rewritten)
        elog_node_display(LOG, "rewritten parse tree", querytree_list,
                          Debug_pretty_print);
 
    return querytree_list;
}

References CMD_UTILITY, Query::commandType, copyObject, Debug_pretty_print, Debug_print_parse, Debug_print_rewritten, elog, elog_node_display(), equal(), lappend(), lfirst_node, list_make1, LOG, log_parser_stats, new_list(), NIL, nodeToStringWithLocations(), pfree(), QueryRewrite(), ResetUsage(), ShowUsage(), str, and WARNING.

Referenced by fmgr_sql_validator(), init_sql_fcache(), inline_set_returning_function(), pg_analyze_and_rewrite_fixedparams(), pg_analyze_and_rewrite_varparams(), and pg_analyze_and_rewrite_withcb().

PostgresMain()

void PostgresMain	(	const char *	dbname,
		const char *	username
	)

Definition at line 4264 of file postgres.c.

{
    sigjmp_buf  local_sigjmp_buf;
 
    /* these must be volatile to ensure state is preserved across longjmp: */
    volatile bool send_ready_for_query = true;
    volatile bool idle_in_transaction_timeout_enabled = false;
    volatile bool idle_session_timeout_enabled = false;
 
    Assert(dbname != NULL);
    Assert(username != NULL);
 
    Assert(GetProcessingMode() == InitProcessing);
 
    /*
     * Set up signal handlers.  (InitPostmasterChild or InitStandaloneProcess
     * has already set up BlockSig and made that the active signal mask.)
     *
     * Note that postmaster blocked all signals before forking child process,
     * so there is no race condition whereby we might receive a signal before
     * we have set up the handler.
     *
     * Also note: it's best not to use any signals that are SIG_IGNored in the
     * postmaster.  If such a signal arrives before we are able to change the
     * handler to non-SIG_IGN, it'll get dropped.  Instead, make a dummy
     * handler in the postmaster to reserve the signal. (Of course, this isn't
     * an issue for signals that are locally generated, such as SIGALRM and
     * SIGPIPE.)
     */
    if (am_walsender)
        WalSndSignals();
    else
    {
        pqsignal(SIGHUP, SignalHandlerForConfigReload);
        pqsignal(SIGINT, StatementCancelHandler);   /* cancel current query */
        pqsignal(SIGTERM, die); /* cancel current query and exit */
 
        /*
         * In a postmaster child backend, replace SignalHandlerForCrashExit
         * with quickdie, so we can tell the client we're dying.
         *
         * In a standalone backend, SIGQUIT can be generated from the keyboard
         * easily, while SIGTERM cannot, so we make both signals do die()
         * rather than quickdie().
         */
        if (IsUnderPostmaster)
            pqsignal(SIGQUIT, quickdie);    /* hard crash time */
        else
            pqsignal(SIGQUIT, die); /* cancel current query and exit */
        InitializeTimeouts();   /* establishes SIGALRM handler */
 
        /*
         * Ignore failure to write to frontend. Note: if frontend closes
         * connection, we will notice it and exit cleanly when control next
         * returns to outer loop.  This seems safer than forcing exit in the
         * midst of output during who-knows-what operation...
         */
        pqsignal(SIGPIPE, SIG_IGN);
        pqsignal(SIGUSR1, procsignal_sigusr1_handler);
        pqsignal(SIGUSR2, SIG_IGN);
        pqsignal(SIGFPE, FloatExceptionHandler);
 
        /*
         * Reset some signals that are accepted by postmaster but not by
         * backend
         */
        pqsignal(SIGCHLD, SIG_DFL); /* system() requires this on some
                                     * platforms */
    }
 
    /* Early initialization */
    BaseInit();
 
    /* We need to allow SIGINT, etc during the initial transaction */
    sigprocmask(SIG_SETMASK, &UnBlockSig, NULL);
 
    /*
     * Generate a random cancel key, if this is a backend serving a
     * connection. InitPostgres() will advertise it in shared memory.
     */
    Assert(!MyCancelKeyValid);
    if (whereToSendOutput == DestRemote)
    {
        if (!pg_strong_random(&MyCancelKey, sizeof(int32)))
        {
            ereport(ERROR,
                    (errcode(ERRCODE_INTERNAL_ERROR),
                     errmsg("could not generate random cancel key")));
        }
        MyCancelKeyValid = true;
    }
 
    /*
     * General initialization.
     *
     * NOTE: if you are tempted to add code in this vicinity, consider putting
     * it inside InitPostgres() instead.  In particular, anything that
     * involves database access should be there, not here.
     *
     * Honor session_preload_libraries if not dealing with a WAL sender.
     */
    InitPostgres(dbname, InvalidOid,    /* database to connect to */
                 username, InvalidOid,  /* role to connect as */
                 (!am_walsender) ? INIT_PG_LOAD_SESSION_LIBS : 0,
                 NULL);         /* no out_dbname */
 
    /*
     * If the PostmasterContext is still around, recycle the space; we don't
     * need it anymore after InitPostgres completes.
     */
    if (PostmasterContext)
    {
        MemoryContextDelete(PostmasterContext);
        PostmasterContext = NULL;
    }
 
    SetProcessingMode(NormalProcessing);
 
    /*
     * Now all GUC states are fully set up.  Report them to client if
     * appropriate.
     */
    BeginReportingGUCOptions();
 
    /*
     * Also set up handler to log session end; we have to wait till now to be
     * sure Log_disconnections has its final value.
     */
    if (IsUnderPostmaster && Log_disconnections)
        on_proc_exit(log_disconnections, 0);
 
    pgstat_report_connect(MyDatabaseId);
 
    /* Perform initialization specific to a WAL sender process. */
    if (am_walsender)
        InitWalSender();
 
    /*
     * Send this backend's cancellation info to the frontend.
     */
    if (whereToSendOutput == DestRemote)
    {
        StringInfoData buf;
 
        Assert(MyCancelKeyValid);
        pq_beginmessage(&buf, PqMsg_BackendKeyData);
        pq_sendint32(&buf, (int32) MyProcPid);
        pq_sendint32(&buf, (int32) MyCancelKey);
        pq_endmessage(&buf);
        /* Need not flush since ReadyForQuery will do it. */
    }
 
    /* Welcome banner for standalone case */
    if (whereToSendOutput == DestDebug)
        printf("\nPostgreSQL stand-alone backend %s\n", PG_VERSION);
 
    /*
     * Create the memory context we will use in the main loop.
     *
     * MessageContext is reset once per iteration of the main loop, ie, upon
     * completion of processing of each command message from the client.
     */
    MessageContext = AllocSetContextCreate(TopMemoryContext,
                                           "MessageContext",
                                           ALLOCSET_DEFAULT_SIZES);
 
    /*
     * Create memory context and buffer used for RowDescription messages. As
     * SendRowDescriptionMessage(), via exec_describe_statement_message(), is
     * frequently executed for ever single statement, we don't want to
     * allocate a separate buffer every time.
     */
    row_description_context = AllocSetContextCreate(TopMemoryContext,
                                                    "RowDescriptionContext",
                                                    ALLOCSET_DEFAULT_SIZES);
    MemoryContextSwitchTo(row_description_context);
    initStringInfo(&row_description_buf);
    MemoryContextSwitchTo(TopMemoryContext);
 
    /* Fire any defined login event triggers, if appropriate */
    EventTriggerOnLogin();
 
    /*
     * POSTGRES main processing loop begins here
     *
     * If an exception is encountered, processing resumes here so we abort the
     * current transaction and start a new one.
     *
     * You might wonder why this isn't coded as an infinite loop around a
     * PG_TRY construct.  The reason is that this is the bottom of the
     * exception stack, and so with PG_TRY there would be no exception handler
     * in force at all during the CATCH part.  By leaving the outermost setjmp
     * always active, we have at least some chance of recovering from an error
     * during error recovery.  (If we get into an infinite loop thereby, it
     * will soon be stopped by overflow of elog.c's internal state stack.)
     *
     * Note that we use sigsetjmp(..., 1), so that this function's signal mask
     * (to wit, UnBlockSig) will be restored when longjmp'ing to here.  This
     * is essential in case we longjmp'd out of a signal handler on a platform
     * where that leaves the signal blocked.  It's not redundant with the
     * unblock in AbortTransaction() because the latter is only called if we
     * were inside a transaction.
     */
 
    if (sigsetjmp(local_sigjmp_buf, 1) != 0)
    {
        /*
         * NOTE: if you are tempted to add more code in this if-block,
         * consider the high probability that it should be in
         * AbortTransaction() instead.  The only stuff done directly here
         * should be stuff that is guaranteed to apply *only* for outer-level
         * error recovery, such as adjusting the FE/BE protocol status.
         */
 
        /* Since not using PG_TRY, must reset error stack by hand */
        error_context_stack = NULL;
 
        /* Prevent interrupts while cleaning up */
        HOLD_INTERRUPTS();
 
        /*
         * Forget any pending QueryCancel request, since we're returning to
         * the idle loop anyway, and cancel any active timeout requests.  (In
         * future we might want to allow some timeout requests to survive, but
         * at minimum it'd be necessary to do reschedule_timeouts(), in case
         * we got here because of a query cancel interrupting the SIGALRM
         * interrupt handler.)  Note in particular that we must clear the
         * statement and lock timeout indicators, to prevent any future plain
         * query cancels from being misreported as timeouts in case we're
         * forgetting a timeout cancel.
         */
        disable_all_timeouts(false);    /* do first to avoid race condition */
        QueryCancelPending = false;
        idle_in_transaction_timeout_enabled = false;
        idle_session_timeout_enabled = false;
 
        /* Not reading from the client anymore. */
        DoingCommandRead = false;
 
        /* Make sure libpq is in a good state */
        pq_comm_reset();
 
        /* Report the error to the client and/or server log */
        EmitErrorReport();
 
        /*
         * If Valgrind noticed something during the erroneous query, print the
         * query string, assuming we have one.
         */
        valgrind_report_error_query(debug_query_string);
 
        /*
         * Make sure debug_query_string gets reset before we possibly clobber
         * the storage it points at.
         */
        debug_query_string = NULL;
 
        /*
         * Abort the current transaction in order to recover.
         */
        AbortCurrentTransaction();
 
        if (am_walsender)
            WalSndErrorCleanup();
 
        PortalErrorCleanup();
 
        /*
         * We can't release replication slots inside AbortTransaction() as we
         * need to be able to start and abort transactions while having a slot
         * acquired. But we never need to hold them across top level errors,
         * so releasing here is fine. There also is a before_shmem_exit()
         * callback ensuring correct cleanup on FATAL errors.
         */
        if (MyReplicationSlot != NULL)
            ReplicationSlotRelease();
 
        /* We also want to cleanup temporary slots on error. */
        ReplicationSlotCleanup(false);
 
        jit_reset_after_error();
 
        /*
         * Now return to normal top-level context and clear ErrorContext for
         * next time.
         */
        MemoryContextSwitchTo(MessageContext);
        FlushErrorState();
 
        /*
         * If we were handling an extended-query-protocol message, initiate
         * skip till next Sync.  This also causes us not to issue
         * ReadyForQuery (until we get Sync).
         */
        if (doing_extended_query_message)
            ignore_till_sync = true;
 
        /* We don't have a transaction command open anymore */
        xact_started = false;
 
        /*
         * If an error occurred while we were reading a message from the
         * client, we have potentially lost track of where the previous
         * message ends and the next one begins.  Even though we have
         * otherwise recovered from the error, we cannot safely read any more
         * messages from the client, so there isn't much we can do with the
         * connection anymore.
         */
        if (pq_is_reading_msg())
            ereport(FATAL,
                    (errcode(ERRCODE_PROTOCOL_VIOLATION),
                     errmsg("terminating connection because protocol synchronization was lost")));
 
        /* Now we can allow interrupts again */
        RESUME_INTERRUPTS();
    }
 
    /* We can now handle ereport(ERROR) */
    PG_exception_stack = &local_sigjmp_buf;
 
    if (!ignore_till_sync)
        send_ready_for_query = true;    /* initially, or after error */
 
    /*
     * Non-error queries loop here.
     */
 
    for (;;)
    {
        int         firstchar;
        StringInfoData input_message;
 
        /*
         * At top of loop, reset extended-query-message flag, so that any
         * errors encountered in "idle" state don't provoke skip.
         */
        doing_extended_query_message = false;
 
        /*
         * For valgrind reporting purposes, the "current query" begins here.
         */
#ifdef USE_VALGRIND
        old_valgrind_error_count = VALGRIND_COUNT_ERRORS;
#endif
 
        /*
         * Release storage left over from prior query cycle, and create a new
         * query input buffer in the cleared MessageContext.
         */
        MemoryContextSwitchTo(MessageContext);
        MemoryContextReset(MessageContext);
 
        initStringInfo(&input_message);
 
        /*
         * Also consider releasing our catalog snapshot if any, so that it's
         * not preventing advance of global xmin while we wait for the client.
         */
        InvalidateCatalogSnapshotConditionally();
 
        /*
         * (1) If we've reached idle state, tell the frontend we're ready for
         * a new query.
         *
         * Note: this includes fflush()'ing the last of the prior output.
         *
         * This is also a good time to flush out collected statistics to the
         * cumulative stats system, and to update the PS stats display.  We
         * avoid doing those every time through the message loop because it'd
         * slow down processing of batched messages, and because we don't want
         * to report uncommitted updates (that confuses autovacuum).  The
         * notification processor wants a call too, if we are not in a
         * transaction block.
         *
         * Also, if an idle timeout is enabled, start the timer for that.
         */
        if (send_ready_for_query)
        {
            if (IsAbortedTransactionBlockState())
            {
                set_ps_display("idle in transaction (aborted)");
                pgstat_report_activity(STATE_IDLEINTRANSACTION_ABORTED, NULL);
 
                /* Start the idle-in-transaction timer */
                if (IdleInTransactionSessionTimeout > 0
                    && (IdleInTransactionSessionTimeout < TransactionTimeout || TransactionTimeout == 0))
                {
                    idle_in_transaction_timeout_enabled = true;
                    enable_timeout_after(IDLE_IN_TRANSACTION_SESSION_TIMEOUT,
                                         IdleInTransactionSessionTimeout);
                }
            }
            else if (IsTransactionOrTransactionBlock())
            {
                set_ps_display("idle in transaction");
                pgstat_report_activity(STATE_IDLEINTRANSACTION, NULL);
 
                /* Start the idle-in-transaction timer */
                if (IdleInTransactionSessionTimeout > 0
                    && (IdleInTransactionSessionTimeout < TransactionTimeout || TransactionTimeout == 0))
                {
                    idle_in_transaction_timeout_enabled = true;
                    enable_timeout_after(IDLE_IN_TRANSACTION_SESSION_TIMEOUT,
                                         IdleInTransactionSessionTimeout);
                }
            }
            else
            {
                long        stats_timeout;
 
                /*
                 * Process incoming notifies (including self-notifies), if
                 * any, and send relevant messages to the client.  Doing it
                 * here helps ensure stable behavior in tests: if any notifies
                 * were received during the just-finished transaction, they'll
                 * be seen by the client before ReadyForQuery is.
                 */
                if (notifyInterruptPending)
                    ProcessNotifyInterrupt(false);
 
                /*
                 * Check if we need to report stats. If pgstat_report_stat()
                 * decides it's too soon to flush out pending stats / lock
                 * contention prevented reporting, it'll tell us when we
                 * should try to report stats again (so that stats updates
                 * aren't unduly delayed if the connection goes idle for a
                 * long time). We only enable the timeout if we don't already
                 * have a timeout in progress, because we don't disable the
                 * timeout below. enable_timeout_after() needs to determine
                 * the current timestamp, which can have a negative
                 * performance impact. That's OK because pgstat_report_stat()
                 * won't have us wake up sooner than a prior call.
                 */
                stats_timeout = pgstat_report_stat(false);
                if (stats_timeout > 0)
                {
                    if (!get_timeout_active(IDLE_STATS_UPDATE_TIMEOUT))
                        enable_timeout_after(IDLE_STATS_UPDATE_TIMEOUT,
                                             stats_timeout);
                }
                else
                {
                    /* all stats flushed, no need for the timeout */
                    if (get_timeout_active(IDLE_STATS_UPDATE_TIMEOUT))
                        disable_timeout(IDLE_STATS_UPDATE_TIMEOUT, false);
                }
 
                set_ps_display("idle");
                pgstat_report_activity(STATE_IDLE, NULL);
 
                /* Start the idle-session timer */
                if (IdleSessionTimeout > 0)
                {
                    idle_session_timeout_enabled = true;
                    enable_timeout_after(IDLE_SESSION_TIMEOUT,
                                         IdleSessionTimeout);
                }
            }
 
            /* Report any recently-changed GUC options */
            ReportChangedGUCOptions();
 
            ReadyForQuery(whereToSendOutput);
            send_ready_for_query = false;
        }
 
        /*
         * (2) Allow asynchronous signals to be executed immediately if they
         * come in while we are waiting for client input. (This must be
         * conditional since we don't want, say, reads on behalf of COPY FROM
         * STDIN doing the same thing.)
         */
        DoingCommandRead = true;
 
        /*
         * (3) read a command (loop blocks here)
         */
        firstchar = ReadCommand(&input_message);
 
        /*
         * (4) turn off the idle-in-transaction and idle-session timeouts if
         * active.  We do this before step (5) so that any last-moment timeout
         * is certain to be detected in step (5).
         *
         * At most one of these timeouts will be active, so there's no need to
         * worry about combining the timeout.c calls into one.
         */
        if (idle_in_transaction_timeout_enabled)
        {
            disable_timeout(IDLE_IN_TRANSACTION_SESSION_TIMEOUT, false);
            idle_in_transaction_timeout_enabled = false;
        }
        if (idle_session_timeout_enabled)
        {
            disable_timeout(IDLE_SESSION_TIMEOUT, false);
            idle_session_timeout_enabled = false;
        }
 
        /*
         * (5) disable async signal conditions again.
         *
         * Query cancel is supposed to be a no-op when there is no query in
         * progress, so if a query cancel arrived while we were idle, just
         * reset QueryCancelPending. ProcessInterrupts() has that effect when
         * it's called when DoingCommandRead is set, so check for interrupts
         * before resetting DoingCommandRead.
         */
        CHECK_FOR_INTERRUPTS();
        DoingCommandRead = false;
 
        /*
         * (6) check for any other interesting events that happened while we
         * slept.
         */
        if (ConfigReloadPending)
        {
            ConfigReloadPending = false;
            ProcessConfigFile(PGC_SIGHUP);
        }
 
        /*
         * (7) process the command.  But ignore it if we're skipping till
         * Sync.
         */
        if (ignore_till_sync && firstchar != EOF)
            continue;
 
        switch (firstchar)
        {
            case PqMsg_Query:
                {
                    const char *query_string;
 
                    /* Set statement_timestamp() */
                    SetCurrentStatementStartTimestamp();
 
                    query_string = pq_getmsgstring(&input_message);
                    pq_getmsgend(&input_message);
 
                    if (am_walsender)
                    {
                        if (!exec_replication_command(query_string))
                            exec_simple_query(query_string);
                    }
                    else
                        exec_simple_query(query_string);
 
                    valgrind_report_error_query(query_string);
 
                    send_ready_for_query = true;
                }
                break;
 
            case PqMsg_Parse:
                {
                    const char *stmt_name;
                    const char *query_string;
                    int         numParams;
                    Oid        *paramTypes = NULL;
 
                    forbidden_in_wal_sender(firstchar);
 
                    /* Set statement_timestamp() */
                    SetCurrentStatementStartTimestamp();
 
                    stmt_name = pq_getmsgstring(&input_message);
                    query_string = pq_getmsgstring(&input_message);
                    numParams = pq_getmsgint(&input_message, 2);
                    if (numParams > 0)
                    {
                        paramTypes = palloc_array(Oid, numParams);
                        for (int i = 0; i < numParams; i++)
                            paramTypes[i] = pq_getmsgint(&input_message, 4);
                    }
                    pq_getmsgend(&input_message);
 
                    exec_parse_message(query_string, stmt_name,
                                       paramTypes, numParams);
 
                    valgrind_report_error_query(query_string);
                }
                break;
 
            case PqMsg_Bind:
                forbidden_in_wal_sender(firstchar);
 
                /* Set statement_timestamp() */
                SetCurrentStatementStartTimestamp();
 
                /*
                 * this message is complex enough that it seems best to put
                 * the field extraction out-of-line
                 */
                exec_bind_message(&input_message);
 
                /* exec_bind_message does valgrind_report_error_query */
                break;
 
            case PqMsg_Execute:
                {
                    const char *portal_name;
                    int         max_rows;
 
                    forbidden_in_wal_sender(firstchar);
 
                    /* Set statement_timestamp() */
                    SetCurrentStatementStartTimestamp();
 
                    portal_name = pq_getmsgstring(&input_message);
                    max_rows = pq_getmsgint(&input_message, 4);
                    pq_getmsgend(&input_message);
 
                    exec_execute_message(portal_name, max_rows);
 
                    /* exec_execute_message does valgrind_report_error_query */
                }
                break;
 
            case PqMsg_FunctionCall:
                forbidden_in_wal_sender(firstchar);
 
                /* Set statement_timestamp() */
                SetCurrentStatementStartTimestamp();
 
                /* Report query to various monitoring facilities. */
                pgstat_report_activity(STATE_FASTPATH, NULL);
                set_ps_display("<FASTPATH>");
 
                /* start an xact for this function invocation */
                start_xact_command();
 
                /*
                 * Note: we may at this point be inside an aborted
                 * transaction.  We can't throw error for that until we've
                 * finished reading the function-call message, so
                 * HandleFunctionRequest() must check for it after doing so.
                 * Be careful not to do anything that assumes we're inside a
                 * valid transaction here.
                 */
 
                /* switch back to message context */
                MemoryContextSwitchTo(MessageContext);
 
                HandleFunctionRequest(&input_message);
 
                /* commit the function-invocation transaction */
                finish_xact_command();
 
                valgrind_report_error_query("fastpath function call");
 
                send_ready_for_query = true;
                break;
 
            case PqMsg_Close:
                {
                    int         close_type;
                    const char *close_target;
 
                    forbidden_in_wal_sender(firstchar);
 
                    close_type = pq_getmsgbyte(&input_message);
                    close_target = pq_getmsgstring(&input_message);
                    pq_getmsgend(&input_message);
 
                    switch (close_type)
                    {
                        case 'S':
                            if (close_target[0] != '\0')
                                DropPreparedStatement(close_target, false);
                            else
                            {
                                /* special-case the unnamed statement */
                                drop_unnamed_stmt();
                            }
                            break;
                        case 'P':
                            {
                                Portal      portal;
 
                                portal = GetPortalByName(close_target);
                                if (PortalIsValid(portal))
                                    PortalDrop(portal, false);
                            }
                            break;
                        default:
                            ereport(ERROR,
                                    (errcode(ERRCODE_PROTOCOL_VIOLATION),
                                     errmsg("invalid CLOSE message subtype %d",
                                            close_type)));
                            break;
                    }
 
                    if (whereToSendOutput == DestRemote)
                        pq_putemptymessage(PqMsg_CloseComplete);
 
                    valgrind_report_error_query("CLOSE message");
                }
                break;
 
            case PqMsg_Describe:
                {
                    int         describe_type;
                    const char *describe_target;
 
                    forbidden_in_wal_sender(firstchar);
 
                    /* Set statement_timestamp() (needed for xact) */
                    SetCurrentStatementStartTimestamp();
 
                    describe_type = pq_getmsgbyte(&input_message);
                    describe_target = pq_getmsgstring(&input_message);
                    pq_getmsgend(&input_message);
 
                    switch (describe_type)
                    {
                        case 'S':
                            exec_describe_statement_message(describe_target);
                            break;
                        case 'P':
                            exec_describe_portal_message(describe_target);
                            break;
                        default:
                            ereport(ERROR,
                                    (errcode(ERRCODE_PROTOCOL_VIOLATION),
                                     errmsg("invalid DESCRIBE message subtype %d",
                                            describe_type)));
                            break;
                    }
 
                    valgrind_report_error_query("DESCRIBE message");
                }
                break;
 
            case PqMsg_Flush:
                pq_getmsgend(&input_message);
                if (whereToSendOutput == DestRemote)
                    pq_flush();
                break;
 
            case PqMsg_Sync:
                pq_getmsgend(&input_message);
 
                /*
                 * If pipelining was used, we may be in an implicit
                 * transaction block. Close it before calling
                 * finish_xact_command.
                 */
                EndImplicitTransactionBlock();
                finish_xact_command();
                valgrind_report_error_query("SYNC message");
                send_ready_for_query = true;
                break;
 
                /*
                 * 'X' means that the frontend is closing down the socket. EOF
                 * means unexpected loss of frontend connection. Either way,
                 * perform normal shutdown.
                 */
            case EOF:
 
                /* for the cumulative statistics system */
                pgStatSessionEndCause = DISCONNECT_CLIENT_EOF;
 
                /* FALLTHROUGH */
 
            case PqMsg_Terminate:
 
                /*
                 * Reset whereToSendOutput to prevent ereport from attempting
                 * to send any more messages to client.
                 */
                if (whereToSendOutput == DestRemote)
                    whereToSendOutput = DestNone;
 
                /*
                 * NOTE: if you are tempted to add more code here, DON'T!
                 * Whatever you had in mind to do should be set up as an
                 * on_proc_exit or on_shmem_exit callback, instead. Otherwise
                 * it will fail to be called during other backend-shutdown
                 * scenarios.
                 */
                proc_exit(0);
 
            case PqMsg_CopyData:
            case PqMsg_CopyDone:
            case PqMsg_CopyFail:
 
                /*
                 * Accept but ignore these messages, per protocol spec; we
                 * probably got here because a COPY failed, and the frontend
                 * is still sending data.
                 */
                break;
 
            default:
                ereport(FATAL,
                        (errcode(ERRCODE_PROTOCOL_VIOLATION),
                         errmsg("invalid frontend message type %d",
                                firstchar)));
        }
    }                           /* end of input-reading loop */
}

References AbortCurrentTransaction(), ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, am_walsender, Assert, BaseInit(), BeginReportingGUCOptions(), buf, CHECK_FOR_INTERRUPTS, ConfigReloadPending, dbname, debug_query_string, DestDebug, DestNone, DestRemote, die(), disable_all_timeouts(), disable_timeout(), DISCONNECT_CLIENT_EOF, doing_extended_query_message, DoingCommandRead, drop_unnamed_stmt(), DropPreparedStatement(), EmitErrorReport(), enable_timeout_after(), EndImplicitTransactionBlock(), ereport, errcode(), errmsg(), ERROR, error_context_stack, EventTriggerOnLogin(), exec_bind_message(), exec_describe_portal_message(), exec_describe_statement_message(), exec_execute_message(), exec_parse_message(), exec_replication_command(), exec_simple_query(), FATAL, finish_xact_command(), FloatExceptionHandler(), FlushErrorState(), forbidden_in_wal_sender(), get_timeout_active(), GetPortalByName(), GetProcessingMode, HandleFunctionRequest(), HOLD_INTERRUPTS, i, IDLE_IN_TRANSACTION_SESSION_TIMEOUT, IDLE_SESSION_TIMEOUT, IDLE_STATS_UPDATE_TIMEOUT, IdleInTransactionSessionTimeout, IdleSessionTimeout, ignore_till_sync, INIT_PG_LOAD_SESSION_LIBS, InitializeTimeouts(), InitPostgres(), InitProcessing, initStringInfo(), InitWalSender(), InvalidateCatalogSnapshotConditionally(), InvalidOid, IsAbortedTransactionBlockState(), IsTransactionOrTransactionBlock(), IsUnderPostmaster, jit_reset_after_error(), Log_disconnections, log_disconnections(), MemoryContextDelete(), MemoryContextReset(), MemoryContextSwitchTo(), MessageContext, MyCancelKey, MyCancelKeyValid, MyDatabaseId, MyProcPid, MyReplicationSlot, NormalProcessing, notifyInterruptPending, on_proc_exit(), palloc_array, PG_exception_stack, pg_strong_random(), PGC_SIGHUP, pgstat_report_activity(), pgstat_report_connect(), pgstat_report_stat(), pgStatSessionEndCause, PortalDrop(), PortalErrorCleanup(), PortalIsValid, PostmasterContext, pq_beginmessage(), pq_comm_reset, pq_endmessage(), pq_flush, pq_getmsgbyte(), pq_getmsgend(), pq_getmsgint(), pq_getmsgstring(), pq_is_reading_msg(), pq_putemptymessage(), pq_sendint32(), PqMsg_BackendKeyData, PqMsg_Bind, PqMsg_Close, PqMsg_CloseComplete, PqMsg_CopyData, PqMsg_CopyDone, PqMsg_CopyFail, PqMsg_Describe, PqMsg_Execute, PqMsg_Flush, PqMsg_FunctionCall, PqMsg_Parse, PqMsg_Query, PqMsg_Sync, PqMsg_Terminate, pqsignal(), printf, proc_exit(), ProcessConfigFile(), ProcessNotifyInterrupt(), procsignal_sigusr1_handler(), QueryCancelPending, quickdie(), ReadCommand(), ReadyForQuery(), ReplicationSlotCleanup(), ReplicationSlotRelease(), ReportChangedGUCOptions(), RESUME_INTERRUPTS, row_description_buf, row_description_context, set_ps_display(), SetCurrentStatementStartTimestamp(), SetProcessingMode, SIG_DFL, SIG_IGN, SIGCHLD, SIGHUP, SignalHandlerForConfigReload(), SIGPIPE, SIGQUIT, SIGUSR1, SIGUSR2, start_xact_command(), STATE_FASTPATH, STATE_IDLE, STATE_IDLEINTRANSACTION, STATE_IDLEINTRANSACTION_ABORTED, StatementCancelHandler(), TopMemoryContext, TransactionTimeout, UnBlockSig, username, valgrind_report_error_query, WalSndErrorCleanup(), WalSndSignals(), whereToSendOutput, and xact_started.

Referenced by BackendMain(), and PostgresSingleUserMain().

PostgresSingleUserMain()

void PostgresSingleUserMain	(	int	argc,
		char *	argv[],
		const char *	username
	)

Definition at line 4145 of file postgres.c.

{
    const char *dbname = NULL;
 
    Assert(!IsUnderPostmaster);
 
    /* Initialize startup process environment. */
    InitStandaloneProcess(argv[0]);
 
    /*
     * Set default values for command-line options.
     */
    InitializeGUCOptions();
 
    /*
     * Parse command-line options.
     */
    process_postgres_switches(argc, argv, PGC_POSTMASTER, &dbname);
 
    /* Must have gotten a database name, or have a default (the username) */
    if (dbname == NULL)
    {
        dbname = username;
        if (dbname == NULL)
            ereport(FATAL,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("%s: no database nor user name specified",
                            progname)));
    }
 
    /* Acquire configuration parameters */
    if (!SelectConfigFiles(userDoption, progname))
        proc_exit(1);
 
    /*
     * Validate we have been given a reasonable-looking DataDir and change
     * into it.
     */
    checkDataDir();
    ChangeToDataDir();
 
    /*
     * Create lockfile for data directory.
     */
    CreateDataDirLockFile(false);
 
    /* read control file (error checking and contains config ) */
    LocalProcessControlFile(false);
 
    /*
     * process any libraries that should be preloaded at postmaster start
     */
    process_shared_preload_libraries();
 
    /* Initialize MaxBackends */
    InitializeMaxBackends();
 
    /*
     * We don't need postmaster child slots in single-user mode, but
     * initialize them anyway to avoid having special handling.
     */
    InitPostmasterChildSlots();
 
    /* Initialize size of fast-path lock cache. */
    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();
 
    CreateSharedMemoryAndSemaphores();
 
    /*
     * Remember stand-alone backend startup time,roughly at the same point
     * during startup that postmaster does so.
     */
    PgStartTime = GetCurrentTimestamp();
 
    /*
     * Create a per-backend PGPROC struct in shared memory. We must do this
     * before we can use LWLocks.
     */
    InitProcess();
 
    /*
     * Now that sufficient infrastructure has been initialized, PostgresMain()
     * can do the rest.
     */
    PostgresMain(dbname, username);
}

References Assert, ChangeToDataDir(), checkDataDir(), CreateDataDirLockFile(), CreateSharedMemoryAndSemaphores(), dbname, ereport, errcode(), errmsg(), FATAL, GetCurrentTimestamp(), InitializeFastPathLocks(), InitializeGUCOptions(), InitializeMaxBackends(), InitializeShmemGUCs(), InitializeWalConsistencyChecking(), InitPostmasterChildSlots(), InitProcess(), InitStandaloneProcess(), IsUnderPostmaster, LocalProcessControlFile(), PGC_POSTMASTER, PgStartTime, PostgresMain(), proc_exit(), process_postgres_switches(), process_shared_preload_libraries(), process_shmem_requests(), progname, SelectConfigFiles(), userDoption, and username.

Referenced by main().

process_postgres_switches()

void process_postgres_switches	(	int	argc,
		char *	argv[],
		GucContext	ctx,
		const char **	dbname
	)

Definition at line 3893 of file postgres.c.

{
    bool        secure = (ctx == PGC_POSTMASTER);
    int         errs = 0;
    GucSource   gucsource;
    int         flag;
 
    if (secure)
    {
        gucsource = PGC_S_ARGV; /* switches came from command line */
 
        /* Ignore the initial --single argument, if present */
        if (argc > 1 && strcmp(argv[1], "--single") == 0)
        {
            argv++;
            argc--;
        }
    }
    else
    {
        gucsource = PGC_S_CLIENT;   /* switches came from client */
    }
 
#ifdef HAVE_INT_OPTERR
 
    /*
     * Turn this off because it's either printed to stderr and not the log
     * where we'd want it, or argv[0] is now "--single", which would make for
     * a weird error message.  We print our own error message below.
     */
    opterr = 0;
#endif
 
    /*
     * Parse command-line options.  CAUTION: keep this in sync with
     * postmaster/postmaster.c (the option sets should not conflict) and with
     * the common help() function in main/main.c.
     */
    while ((flag = getopt(argc, argv, "B:bC:c:D:d:EeFf:h:ijk:lN:nOPp:r:S:sTt:v:W:-:")) != -1)
    {
        switch (flag)
        {
            case 'B':
                SetConfigOption("shared_buffers", optarg, ctx, gucsource);
                break;
 
            case 'b':
                /* Undocumented flag used for binary upgrades */
                if (secure)
                    IsBinaryUpgrade = true;
                break;
 
            case 'C':
                /* ignored for consistency with the postmaster */
                break;
 
            case 'c':
            case '-':
                {
                    char       *name,
                               *value;
 
                    ParseLongOption(optarg, &name, &value);
                    if (!value)
                    {
                        if (flag == '-')
                            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, ctx, gucsource);
                    pfree(name);
                    pfree(value);
                    break;
                }
 
            case 'D':
                if (secure)
                    userDoption = strdup(optarg);
                break;
 
            case 'd':
                set_debug_options(atoi(optarg), ctx, gucsource);
                break;
 
            case 'E':
                if (secure)
                    EchoQuery = true;
                break;
 
            case 'e':
                SetConfigOption("datestyle", "euro", ctx, gucsource);
                break;
 
            case 'F':
                SetConfigOption("fsync", "false", ctx, gucsource);
                break;
 
            case 'f':
                if (!set_plan_disabling_options(optarg, ctx, gucsource))
                    errs++;
                break;
 
            case 'h':
                SetConfigOption("listen_addresses", optarg, ctx, gucsource);
                break;
 
            case 'i':
                SetConfigOption("listen_addresses", "*", ctx, gucsource);
                break;
 
            case 'j':
                if (secure)
                    UseSemiNewlineNewline = true;
                break;
 
            case 'k':
                SetConfigOption("unix_socket_directories", optarg, ctx, gucsource);
                break;
 
            case 'l':
                SetConfigOption("ssl", "true", ctx, gucsource);
                break;
 
            case 'N':
                SetConfigOption("max_connections", optarg, ctx, gucsource);
                break;
 
            case 'n':
                /* ignored for consistency with postmaster */
                break;
 
            case 'O':
                SetConfigOption("allow_system_table_mods", "true", ctx, gucsource);
                break;
 
            case 'P':
                SetConfigOption("ignore_system_indexes", "true", ctx, gucsource);
                break;
 
            case 'p':
                SetConfigOption("port", optarg, ctx, gucsource);
                break;
 
            case 'r':
                /* send output (stdout and stderr) to the given file */
                if (secure)
                    strlcpy(OutputFileName, optarg, MAXPGPATH);
                break;
 
            case 'S':
                SetConfigOption("work_mem", optarg, ctx, gucsource);
                break;
 
            case 's':
                SetConfigOption("log_statement_stats", "true", ctx, gucsource);
                break;
 
            case 'T':
                /* ignored for consistency with the postmaster */
                break;
 
            case 't':
                {
                    const char *tmp = get_stats_option_name(optarg);
 
                    if (tmp)
                        SetConfigOption(tmp, "true", ctx, gucsource);
                    else
                        errs++;
                    break;
                }
 
            case 'v':
 
                /*
                 * -v is no longer used in normal operation, since
                 * FrontendProtocol is already set before we get here. We keep
                 * the switch only for possible use in standalone operation,
                 * in case we ever support using normal FE/BE protocol with a
                 * standalone backend.
                 */
                if (secure)
                    FrontendProtocol = (ProtocolVersion) atoi(optarg);
                break;
 
            case 'W':
                SetConfigOption("post_auth_delay", optarg, ctx, gucsource);
                break;
 
            default:
                errs++;
                break;
        }
 
        if (errs)
            break;
    }
 
    /*
     * Optional database name should be there only if *dbname is NULL.
     */
    if (!errs && dbname && *dbname == NULL && argc - optind >= 1)
        *dbname = strdup(argv[optind++]);
 
    if (errs || argc != optind)
    {
        if (errs)
            optind--;           /* complain about the previous argument */
 
        /* spell the error message a bit differently depending on context */
        if (IsUnderPostmaster)
            ereport(FATAL,
                    errcode(ERRCODE_SYNTAX_ERROR),
                    errmsg("invalid command-line argument for server process: %s", argv[optind]),
                    errhint("Try \"%s --help\" for more information.", progname));
        else
            ereport(FATAL,
                    errcode(ERRCODE_SYNTAX_ERROR),
                    errmsg("%s: invalid command-line argument: %s",
                           progname, argv[optind]),
                    errhint("Try \"%s --help\" for more information.", progname));
    }
 
    /*
     * Reset getopt(3) library so that it will work correctly in subprocesses
     * or when this function is called a second time with another array.
     */
    optind = 1;
#ifdef HAVE_INT_OPTRESET
    optreset = 1;               /* some systems need this too */
#endif
}

References dbname, EchoQuery, ereport, errcode(), errhint(), errmsg(), ERROR, FATAL, flag(), FrontendProtocol, get_stats_option_name(), getopt(), IsBinaryUpgrade, IsUnderPostmaster, MAXPGPATH, name, optarg, opterr, optind, OutputFileName, ParseLongOption(), pfree(), PGC_POSTMASTER, PGC_S_ARGV, PGC_S_CLIENT, progname, set_debug_options(), set_plan_disabling_options(), SetConfigOption(), strlcpy(), userDoption, UseSemiNewlineNewline, and value.

Referenced by PostgresSingleUserMain(), and process_startup_options().

ProcessClientReadInterrupt()

void ProcessClientReadInterrupt

(

bool

blocked

)

Definition at line 512 of file postgres.c.

{
    int         save_errno = errno;
 
    if (DoingCommandRead)
    {
        /* Check for general interrupts that arrived before/while reading */
        CHECK_FOR_INTERRUPTS();
 
        /* Process sinval catchup interrupts, if any */
        if (catchupInterruptPending)
            ProcessCatchupInterrupt();
 
        /* Process notify interrupts, if any */
        if (notifyInterruptPending)
            ProcessNotifyInterrupt(true);
    }
    else if (ProcDiePending)
    {
        /*
         * We're dying.  If there is no data available to read, then it's safe
         * (and sane) to handle that now.  If we haven't tried to read yet,
         * make sure the process latch is set, so that if there is no data
         * then we'll come back here and die.  If we're done reading, also
         * make sure the process latch is set, as we might've undesirably
         * cleared it while reading.
         */
        if (blocked)
            CHECK_FOR_INTERRUPTS();
        else
            SetLatch(MyLatch);
    }
 
    errno = save_errno;
}

References catchupInterruptPending, CHECK_FOR_INTERRUPTS, DoingCommandRead, MyLatch, notifyInterruptPending, ProcDiePending, ProcessCatchupInterrupt(), ProcessNotifyInterrupt(), and SetLatch().

Referenced by interactive_getc(), and secure_read().

ProcessClientWriteInterrupt()

void ProcessClientWriteInterrupt

(

bool

blocked

)

Definition at line 558 of file postgres.c.

{
    int         save_errno = errno;
 
    if (ProcDiePending)
    {
        /*
         * We're dying.  If it's not possible to write, then we should handle
         * that immediately, else a stuck client could indefinitely delay our
         * response to the signal.  If we haven't tried to write yet, make
         * sure the process latch is set, so that if the write would block
         * then we'll come back here and die.  If we're done writing, also
         * make sure the process latch is set, as we might've undesirably
         * cleared it while writing.
         */
        if (blocked)
        {
            /*
             * Don't mess with whereToSendOutput if ProcessInterrupts wouldn't
             * service ProcDiePending.
             */
            if (InterruptHoldoffCount == 0 && CritSectionCount == 0)
            {
                /*
                 * We don't want to send the client the error message, as a)
                 * that would possibly block again, and b) it would likely
                 * lead to loss of protocol sync because we may have already
                 * sent a partial protocol message.
                 */
                if (whereToSendOutput == DestRemote)
                    whereToSendOutput = DestNone;
 
                CHECK_FOR_INTERRUPTS();
            }
        }
        else
            SetLatch(MyLatch);
    }
 
    errno = save_errno;
}

References CHECK_FOR_INTERRUPTS, CritSectionCount, DestNone, DestRemote, InterruptHoldoffCount, MyLatch, ProcDiePending, SetLatch(), and whereToSendOutput.

Referenced by secure_write().

quickdie()

void quickdie

(

SIGNAL_ARGS

)

Definition at line 2918 of file postgres.c.

{
    sigaddset(&BlockSig, SIGQUIT);  /* prevent nested calls */
    sigprocmask(SIG_SETMASK, &BlockSig, NULL);
 
    /*
     * Prevent interrupts while exiting; though we just blocked signals that
     * would queue new interrupts, one may have been pending.  We don't want a
     * quickdie() downgraded to a mere query cancel.
     */
    HOLD_INTERRUPTS();
 
    /*
     * If we're aborting out of client auth, don't risk trying to send
     * anything to the client; we will likely violate the protocol, not to
     * mention that we may have interrupted the guts of OpenSSL or some
     * authentication library.
     */
    if (ClientAuthInProgress && whereToSendOutput == DestRemote)
        whereToSendOutput = DestNone;
 
    /*
     * Notify the client before exiting, to give a clue on what happened.
     *
     * It's dubious to call ereport() from a signal handler.  It is certainly
     * not async-signal safe.  But it seems better to try, than to disconnect
     * abruptly and leave the client wondering what happened.  It's remotely
     * possible that we crash or hang while trying to send the message, but
     * receiving a SIGQUIT is a sign that something has already gone badly
     * wrong, so there's not much to lose.  Assuming the postmaster is still
     * running, it will SIGKILL us soon if we get stuck for some reason.
     *
     * One thing we can do to make this a tad safer is to clear the error
     * context stack, so that context callbacks are not called.  That's a lot
     * less code that could be reached here, and the context info is unlikely
     * to be very relevant to a SIGQUIT report anyway.
     */
    error_context_stack = NULL;
 
    /*
     * When responding to a postmaster-issued signal, we send the message only
     * to the client; sending to the server log just creates log spam, plus
     * it's more code that we need to hope will work in a signal handler.
     *
     * Ideally these should be ereport(FATAL), but then we'd not get control
     * back to force the correct type of process exit.
     */
    switch (GetQuitSignalReason())
    {
        case PMQUIT_NOT_SENT:
            /* Hmm, SIGQUIT arrived out of the blue */
            ereport(WARNING,
                    (errcode(ERRCODE_ADMIN_SHUTDOWN),
                     errmsg("terminating connection because of unexpected SIGQUIT signal")));
            break;
        case PMQUIT_FOR_CRASH:
            /* A crash-and-restart cycle is in progress */
            ereport(WARNING_CLIENT_ONLY,
                    (errcode(ERRCODE_CRASH_SHUTDOWN),
                     errmsg("terminating connection because of crash of another server process"),
                     errdetail("The postmaster has commanded this server process to roll back"
                               " the current transaction and exit, because another"
                               " server process exited abnormally and possibly corrupted"
                               " shared memory."),
                     errhint("In a moment you should be able to reconnect to the"
                             " database and repeat your command.")));
            break;
        case PMQUIT_FOR_STOP:
            /* Immediate-mode stop */
            ereport(WARNING_CLIENT_ONLY,
                    (errcode(ERRCODE_ADMIN_SHUTDOWN),
                     errmsg("terminating connection due to immediate shutdown command")));
            break;
    }
 
    /*
     * We DO NOT want to run proc_exit() or atexit() callbacks -- we're here
     * because shared memory may be corrupted, so we don't want to try to
     * clean up our transaction.  Just nail the windows shut and get out of
     * town.  The callbacks wouldn't be safe to run from a signal handler,
     * anyway.
     *
     * Note we do _exit(2) not _exit(0).  This is to force the postmaster into
     * a system reset cycle if someone sends a manual SIGQUIT to a random
     * backend.  This is necessary precisely because we don't clean up our
     * shared memory state.  (The "dead man switch" mechanism in pmsignal.c
     * should ensure the postmaster sees this as a crash, too, but no harm in
     * being doubly sure.)
     */
    _exit(2);
}

References BlockSig, ClientAuthInProgress, DestNone, DestRemote, ereport, errcode(), errdetail(), errhint(), errmsg(), error_context_stack, GetQuitSignalReason(), HOLD_INTERRUPTS, PMQUIT_FOR_CRASH, PMQUIT_FOR_STOP, PMQUIT_NOT_SENT, SIGQUIT, WARNING, WARNING_CLIENT_ONLY, and whereToSendOutput.

Referenced by PostgresMain().

ResetUsage()

void ResetUsage

(

void

)

Definition at line 5129 of file postgres.c.

{
    getrusage(RUSAGE_SELF, &Save_r);
    gettimeofday(&Save_t, NULL);
}

References getrusage(), gettimeofday(), RUSAGE_SELF, Save_r, and Save_t.

Referenced by _bt_leader_participate_as_worker(), _bt_leafbuild(), _bt_parallel_build_main(), _SPI_pquery(), btbuild(), exec_bind_message(), exec_execute_message(), exec_parse_message(), exec_simple_query(), pg_analyze_and_rewrite_fixedparams(), pg_analyze_and_rewrite_varparams(), pg_analyze_and_rewrite_withcb(), pg_parse_query(), pg_plan_query(), pg_rewrite_query(), PortalRun(), and PortalRunMulti().

set_debug_options()

void set_debug_options	(	int	debug_flag,
		GucContext	context,
		GucSource	source
	)

Definition at line 3782 of file postgres.c.

{
    if (debug_flag > 0)
    {
        char        debugstr[64];
 
        sprintf(debugstr, "debug%d", debug_flag);
        SetConfigOption("log_min_messages", debugstr, context, source);
    }
    else
        SetConfigOption("log_min_messages", "notice", context, source);
 
    if (debug_flag >= 1 && context == PGC_POSTMASTER)
    {
        SetConfigOption("log_connections", "true", context, source);
        SetConfigOption("log_disconnections", "true", context, source);
    }
    if (debug_flag >= 2)
        SetConfigOption("log_statement", "all", context, source);
    if (debug_flag >= 3)
        SetConfigOption("debug_print_parse", "true", context, source);
    if (debug_flag >= 4)
        SetConfigOption("debug_print_plan", "true", context, source);
    if (debug_flag >= 5)
        SetConfigOption("debug_print_rewritten", "true", context, source);
}

References context, PGC_POSTMASTER, SetConfigOption(), source, and sprintf.

Referenced by PostmasterMain(), and process_postgres_switches().

set_plan_disabling_options()

bool set_plan_disabling_options	(	const char *	arg,
		GucContext	context,
		GucSource	source
	)

Definition at line 3811 of file postgres.c.

{
    const char *tmp = NULL;
 
    switch (arg[0])
    {
        case 's':               /* seqscan */
            tmp = "enable_seqscan";
            break;
        case 'i':               /* indexscan */
            tmp = "enable_indexscan";
            break;
        case 'o':               /* indexonlyscan */
            tmp = "enable_indexonlyscan";
            break;
        case 'b':               /* bitmapscan */
            tmp = "enable_bitmapscan";
            break;
        case 't':               /* tidscan */
            tmp = "enable_tidscan";
            break;
        case 'n':               /* nestloop */
            tmp = "enable_nestloop";
            break;
        case 'm':               /* mergejoin */
            tmp = "enable_mergejoin";
            break;
        case 'h':               /* hashjoin */
            tmp = "enable_hashjoin";
            break;
    }
    if (tmp)
    {
        SetConfigOption(tmp, "false", context, source);
        return true;
    }
    else
        return false;
}

References arg, context, SetConfigOption(), and source.

Referenced by PostmasterMain(), and process_postgres_switches().

ShowUsage()

void ShowUsage

(

const char *

title

)

Definition at line 5136 of file postgres.c.

{
    StringInfoData str;
    struct timeval user,
                sys;
    struct timeval elapse_t;
    struct rusage r;
 
    getrusage(RUSAGE_SELF, &r);
    gettimeofday(&elapse_t, NULL);
    memcpy((char *) &user, (char *) &r.ru_utime, sizeof(user));
    memcpy((char *) &sys, (char *) &r.ru_stime, sizeof(sys));
    if (elapse_t.tv_usec < Save_t.tv_usec)
    {
        elapse_t.tv_sec--;
        elapse_t.tv_usec += 1000000;
    }
    if (r.ru_utime.tv_usec < Save_r.ru_utime.tv_usec)
    {
        r.ru_utime.tv_sec--;
        r.ru_utime.tv_usec += 1000000;
    }
    if (r.ru_stime.tv_usec < Save_r.ru_stime.tv_usec)
    {
        r.ru_stime.tv_sec--;
        r.ru_stime.tv_usec += 1000000;
    }
 
    /*
     * The only stats we don't show here are ixrss, idrss, isrss.  It takes
     * some work to interpret them, and most platforms don't fill them in.
     */
    initStringInfo(&str);
 
    appendStringInfoString(&str, "! system usage stats:\n");
    appendStringInfo(&str,
                     "!\t%ld.%06ld s user, %ld.%06ld s system, %ld.%06ld s elapsed\n",
                     (long) (r.ru_utime.tv_sec - Save_r.ru_utime.tv_sec),
                     (long) (r.ru_utime.tv_usec - Save_r.ru_utime.tv_usec),
                     (long) (r.ru_stime.tv_sec - Save_r.ru_stime.tv_sec),
                     (long) (r.ru_stime.tv_usec - Save_r.ru_stime.tv_usec),
                     (long) (elapse_t.tv_sec - Save_t.tv_sec),
                     (long) (elapse_t.tv_usec - Save_t.tv_usec));
    appendStringInfo(&str,
                     "!\t[%ld.%06ld s user, %ld.%06ld s system total]\n",
                     (long) user.tv_sec,
                     (long) user.tv_usec,
                     (long) sys.tv_sec,
                     (long) sys.tv_usec);
#ifndef WIN32
 
    /*
     * The following rusage fields are not defined by POSIX, but they're
     * present on all current Unix-like systems so we use them without any
     * special checks.  Some of these could be provided in our Windows
     * emulation in src/port/win32getrusage.c with more work.
     */
    appendStringInfo(&str,
                     "!\t%ld kB max resident size\n",
#if defined(__darwin__)
    /* in bytes on macOS */
                     r.ru_maxrss / 1024
#else
    /* in kilobytes on most other platforms */
                     r.ru_maxrss
#endif
        );
    appendStringInfo(&str,
                     "!\t%ld/%ld [%ld/%ld] filesystem blocks in/out\n",
                     r.ru_inblock - Save_r.ru_inblock,
    /* they only drink coffee at dec */
                     r.ru_oublock - Save_r.ru_oublock,
                     r.ru_inblock, r.ru_oublock);
    appendStringInfo(&str,
                     "!\t%ld/%ld [%ld/%ld] page faults/reclaims, %ld [%ld] swaps\n",
                     r.ru_majflt - Save_r.ru_majflt,
                     r.ru_minflt - Save_r.ru_minflt,
                     r.ru_majflt, r.ru_minflt,
                     r.ru_nswap - Save_r.ru_nswap,
                     r.ru_nswap);
    appendStringInfo(&str,
                     "!\t%ld [%ld] signals rcvd, %ld/%ld [%ld/%ld] messages rcvd/sent\n",
                     r.ru_nsignals - Save_r.ru_nsignals,
                     r.ru_nsignals,
                     r.ru_msgrcv - Save_r.ru_msgrcv,
                     r.ru_msgsnd - Save_r.ru_msgsnd,
                     r.ru_msgrcv, r.ru_msgsnd);
    appendStringInfo(&str,
                     "!\t%ld/%ld [%ld/%ld] voluntary/involuntary context switches\n",
                     r.ru_nvcsw - Save_r.ru_nvcsw,
                     r.ru_nivcsw - Save_r.ru_nivcsw,
                     r.ru_nvcsw, r.ru_nivcsw);
#endif                          /* !WIN32 */
 
    /* remove trailing newline */
    if (str.data[str.len - 1] == '\n')
        str.data[--str.len] = '\0';
 
    ereport(LOG,
            (errmsg_internal("%s", title),
             errdetail_internal("%s", str.data)));
 
    pfree(str.data);
}

References __darwin__, appendStringInfo(), appendStringInfoString(), ereport, errdetail_internal(), errmsg_internal(), getrusage(), gettimeofday(), initStringInfo(), LOG, pfree(), rusage::ru_stime, rusage::ru_utime, RUSAGE_SELF, Save_r, Save_t, str, and user.

Referenced by _bt_leader_participate_as_worker(), _bt_leafbuild(), _bt_parallel_build_main(), _SPI_pquery(), btbuild(), exec_bind_message(), exec_execute_message(), exec_parse_message(), exec_simple_query(), pg_analyze_and_rewrite_fixedparams(), pg_analyze_and_rewrite_varparams(), pg_analyze_and_rewrite_withcb(), pg_parse_query(), pg_plan_query(), pg_rewrite_query(), PortalRun(), and PortalRunMulti().

StatementCancelHandler()

void StatementCancelHandler

(

SIGNAL_ARGS

)

Definition at line 3045 of file postgres.c.

{
    /*
     * Don't joggle the elbow of proc_exit
     */
    if (!proc_exit_inprogress)
    {
        InterruptPending = true;
        QueryCancelPending = true;
    }
 
    /* If we're still here, waken anything waiting on the process latch */
    SetLatch(MyLatch);
}

References InterruptPending, MyLatch, proc_exit_inprogress, QueryCancelPending, and SetLatch().

Referenced by AutoVacWorkerMain(), BackgroundWorkerMain(), PostgresMain(), and WalSndSignals().

Variable Documentation

client_connection_check_interval

PGDLLIMPORT int client_connection_check_interval

extern

Definition at line 104 of file postgres.c.

Referenced by ProcessInterrupts(), and start_xact_command().

debug_query_string

PGDLLIMPORT const char* debug_query_string

extern

Definition at line 87 of file postgres.c.

Referenced by _brin_begin_parallel(), _brin_parallel_build_main(), _bt_begin_parallel(), _bt_parallel_build_main(), check_log_of_query(), current_query(), errstart(), exec_bind_message(), exec_execute_message(), exec_parse_message(), exec_replication_command(), exec_simple_query(), initialize_worker_spi(), parallel_vacuum_init(), parallel_vacuum_main(), ParallelQueryMain(), PostgresMain(), proc_exit_prepare(), send_message_to_server_log(), worker_spi_main(), write_csvlog(), and write_jsonlog().

Log_disconnections

PGDLLIMPORT bool Log_disconnections

extern

Definition at line 93 of file postgres.c.

Referenced by PostgresMain().

log_statement

PGDLLIMPORT int log_statement

extern

Definition at line 95 of file postgres.c.

Referenced by check_log_statement(), and HandleFunctionRequest().

max_stack_depth

PGDLLIMPORT int max_stack_depth

extern

Definition at line 98 of file postgres.c.

Referenced by check_stack_depth().

PostAuthDelay

PGDLLIMPORT int PostAuthDelay

extern

Definition at line 101 of file postgres.c.

Referenced by AutoVacWorkerMain(), BackgroundWorkerMain(), and InitPostgres().

restrict_nonsystem_relation_kind

PGDLLIMPORT int restrict_nonsystem_relation_kind

extern

Definition at line 107 of file postgres.c.

Referenced by ApplyRetrieveRule(), assign_restrict_nonsystem_relation_kind(), get_relation_info(), GetFdwRoutine(), make_modifytable(), and rewriteTargetView().

whereToSendOutput

PGDLLIMPORT CommandDest whereToSendOutput

extern

Definition at line 90 of file postgres.c.

Referenced by BackendInitialize(), BeginCopyFrom(), BeginCopyTo(), BeginReportingGUCOptions(), die(), DoCopyTo(), errfinish(), exec_bind_message(), exec_describe_portal_message(), exec_describe_statement_message(), exec_execute_message(), exec_parse_message(), exec_simple_query(), NotifyMyFrontEnd(), PostgresMain(), PostmasterMain(), pq_cleanup_redirect_to_shm_mq(), pq_redirect_to_shm_mq(), ProcessClientWriteInterrupt(), ProcessInterrupts(), quickdie(), ReadCommand(), send_message_to_server_log(), should_output_to_client(), SocketBackend(), SyncRepWaitForLSN(), and SysLoggerMain().