/*------------------------------------------------------------------------- * * postgres.c * POSTGRES C Backend Interface * * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION * src/backend/tcop/postgres.c * * NOTES * this is the "main" module of the postgres backend and * hence the main module of the "traffic cop". * *------------------------------------------------------------------------- */ #include "postgres.h" #include #include #include #include #include #ifdef HAVE_SYS_SELECT_H #include #endif #ifdef HAVE_SYS_RESOURCE_H #include #include #endif #ifndef HAVE_GETRUSAGE #include "rusagestub.h" #endif #include "access/parallel.h" #include "access/printtup.h" #include "access/xact.h" #include "catalog/pg_type.h" #include "commands/async.h" #include "commands/prepare.h" #include "jit/jit.h" #include "libpq/libpq.h" #include "libpq/pqformat.h" #include "libpq/pqsignal.h" #include "mb/pg_wchar.h" #include "mb/stringinfo_mb.h" #include "miscadmin.h" #include "nodes/print.h" #include "optimizer/optimizer.h" #include "parser/analyze.h" #include "parser/parser.h" #include "pg_getopt.h" #include "pg_trace.h" #include "pgstat.h" #include "postmaster/autovacuum.h" #include "postmaster/interrupt.h" #include "postmaster/postmaster.h" #include "replication/logicallauncher.h" #include "replication/logicalworker.h" #include "replication/slot.h" #include "replication/walsender.h" #include "rewrite/rewriteHandler.h" #include "storage/bufmgr.h" #include "storage/ipc.h" #include "storage/pmsignal.h" #include "storage/proc.h" #include "storage/procsignal.h" #include "storage/sinval.h" #include "tcop/fastpath.h" #include "tcop/pquery.h" #include "tcop/tcopprot.h" #include "tcop/utility.h" #include "utils/lsyscache.h" #include "utils/memutils.h" #include "utils/ps_status.h" #include "utils/snapmgr.h" #include "utils/timeout.h" #include "utils/timestamp.h" /* ---------------- * global variables * ---------------- */ const char *debug_query_string; /* client-supplied query string */ /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */ CommandDest whereToSendOutput = DestDebug; /* flag for logging end of session */ bool Log_disconnections = false; int log_statement = LOGSTMT_NONE; /* GUC variable for maximum stack depth (measured in kilobytes) */ int max_stack_depth = 100; /* wait N seconds to allow attach from a debugger */ int PostAuthDelay = 0; /* Time between checks that the client is still connected. */ int client_connection_check_interval = 0; /* ---------------- * private typedefs etc * ---------------- */ /* type of argument for bind_param_error_callback */ typedef struct BindParamCbData { const char *portalName; int paramno; /* zero-based param number, or -1 initially */ const char *paramval; /* textual input string, if available */ } BindParamCbData; /* ---------------- * private variables * ---------------- */ /* max_stack_depth converted to bytes for speed of checking */ static long max_stack_depth_bytes = 100 * 1024L; /* * Stack base pointer -- initialized by PostmasterMain and inherited by * subprocesses. This is not static because old versions of PL/Java modify * it directly. Newer versions use set_stack_base(), but we want to stay * binary-compatible for the time being. */ char *stack_base_ptr = NULL; /* * On IA64 we also have to remember the register stack base. */ #if defined(__ia64__) || defined(__ia64) char *register_stack_base_ptr = NULL; #endif /* * Flag to keep track of whether we have started a transaction. * For extended query protocol this has to be remembered across messages. */ static bool xact_started = false; /* * Flag to indicate that we are doing the outer loop's read-from-client, * as opposed to any random read from client that might happen within * commands like COPY FROM STDIN. */ static bool DoingCommandRead = false; /* * Flags to implement skip-till-Sync-after-error behavior for messages of * the extended query protocol. */ static bool doing_extended_query_message = false; static bool ignore_till_sync = false; /* * If an unnamed prepared statement exists, it's stored here. * We keep it separate from the hashtable kept by commands/prepare.c * in order to reduce overhead for short-lived queries. */ static CachedPlanSource *unnamed_stmt_psrc = NULL; /* assorted command-line switches */ static const char *userDoption = NULL; /* -D switch */ static bool EchoQuery = false; /* -E switch */ static bool UseSemiNewlineNewline = false; /* -j switch */ /* whether or not, and why, we were canceled by conflict with recovery */ static bool RecoveryConflictPending = false; static bool RecoveryConflictRetryable = true; static ProcSignalReason RecoveryConflictReason; /* reused buffer to pass to SendRowDescriptionMessage() */ static MemoryContext row_description_context = NULL; static StringInfoData row_description_buf; /* ---------------------------------------------------------------- * decls for routines only used in this file * ---------------------------------------------------------------- */ static int InteractiveBackend(StringInfo inBuf); static int interactive_getc(void); static int SocketBackend(StringInfo inBuf); static int ReadCommand(StringInfo inBuf); static void forbidden_in_wal_sender(char firstchar); static bool check_log_statement(List *stmt_list); static int errdetail_execute(List *raw_parsetree_list); static int errdetail_params(ParamListInfo params); static int errdetail_abort(void); static int errdetail_recovery_conflict(void); static void bind_param_error_callback(void *arg); static void start_xact_command(void); static void finish_xact_command(void); static bool IsTransactionExitStmt(Node *parsetree); static bool IsTransactionExitStmtList(List *pstmts); static bool IsTransactionStmtList(List *pstmts); static void drop_unnamed_stmt(void); static void log_disconnections(int code, Datum arg); static void enable_statement_timeout(void); static void disable_statement_timeout(void); /* ---------------------------------------------------------------- * routines to obtain user input * ---------------------------------------------------------------- */ /* ---------------- * InteractiveBackend() is called for user interactive connections * * the string entered by the user is placed in its parameter inBuf, * and we act like a Q message was received. * * EOF is returned if end-of-file input is seen; time to shut down. * ---------------- */ static int InteractiveBackend(StringInfo inBuf) { int c; /* character read from getc() */ /* * display a prompt and obtain input from the user */ printf("backend> "); fflush(stdout); resetStringInfo(inBuf); /* * Read characters until EOF or the appropriate delimiter is seen. */ while ((c = interactive_getc()) != EOF) { if (c == '\n') { if (UseSemiNewlineNewline) { /* * In -j mode, semicolon followed by two newlines ends the * command; otherwise treat newline as regular character. */ if (inBuf->len > 1 && inBuf->data[inBuf->len - 1] == '\n' && inBuf->data[inBuf->len - 2] == ';') { /* might as well drop the second newline */ break; } } else { /* * In plain mode, newline ends the command unless preceded by * backslash. */ if (inBuf->len > 0 && inBuf->data[inBuf->len - 1] == '\\') { /* discard backslash from inBuf */ inBuf->data[--inBuf->len] = '\0'; /* discard newline too */ continue; } else { /* keep the newline character, but end the command */ appendStringInfoChar(inBuf, '\n'); break; } } } /* Not newline, or newline treated as regular character */ appendStringInfoChar(inBuf, (char) c); } /* No input before EOF signal means time to quit. */ if (c == EOF && inBuf->len == 0) return EOF; /* * otherwise we have a user query so process it. */ /* Add '\0' to make it look the same as message case. */ appendStringInfoChar(inBuf, (char) '\0'); /* * if the query echo flag was given, print the query.. */ if (EchoQuery) printf("statement: %s\n", inBuf->data); fflush(stdout); return 'Q'; } /* * interactive_getc -- collect one character from stdin * * Even though we are not reading from a "client" process, we still want to * respond to signals, particularly SIGTERM/SIGQUIT. */ static int interactive_getc(void) { int c; /* * This will not process catchup interrupts or notifications while * reading. But those can't really be relevant for a standalone backend * anyway. To properly handle SIGTERM there's a hack in die() that * directly processes interrupts at this stage... */ CHECK_FOR_INTERRUPTS(); c = getc(stdin); ProcessClientReadInterrupt(false); return c; } /* ---------------- * SocketBackend() Is called for frontend-backend connections * * Returns the message type code, and loads message body data into inBuf. * * EOF is returned if the connection is lost. * ---------------- */ static int SocketBackend(StringInfo inBuf) { int qtype; int maxmsglen; /* * Get message type code from the frontend. */ HOLD_CANCEL_INTERRUPTS(); pq_startmsgread(); qtype = pq_getbyte(); if (qtype == EOF) /* frontend disconnected */ { if (IsTransactionState()) ereport(COMMERROR, (errcode(ERRCODE_CONNECTION_FAILURE), errmsg("unexpected EOF on client connection with an open transaction"))); else { /* * Can't send DEBUG log messages to client at this point. Since * we're disconnecting right away, we don't need to restore * whereToSendOutput. */ whereToSendOutput = DestNone; ereport(DEBUG1, (errcode(ERRCODE_CONNECTION_DOES_NOT_EXIST), errmsg_internal("unexpected EOF on client connection"))); } return qtype; } /* * Validate message type code before trying to read body; if we have lost * sync, better to say "command unknown" than to run out of memory because * we used garbage as a length word. We can also select a type-dependent * limit on what a sane length word could be. (The limit could be chosen * more granularly, but it's not clear it's worth fussing over.) * * This also gives us a place to set the doing_extended_query_message flag * as soon as possible. */ switch (qtype) { case 'Q': /* simple query */ maxmsglen = PQ_LARGE_MESSAGE_LIMIT; doing_extended_query_message = false; break; case 'F': /* fastpath function call */ maxmsglen = PQ_LARGE_MESSAGE_LIMIT; doing_extended_query_message = false; break; case 'X': /* terminate */ maxmsglen = PQ_SMALL_MESSAGE_LIMIT; doing_extended_query_message = false; ignore_till_sync = false; break; case 'B': /* bind */ case 'P': /* parse */ maxmsglen = PQ_LARGE_MESSAGE_LIMIT; doing_extended_query_message = true; break; case 'C': /* close */ case 'D': /* describe */ case 'E': /* execute */ case 'H': /* flush */ maxmsglen = PQ_SMALL_MESSAGE_LIMIT; doing_extended_query_message = true; break; case 'S': /* sync */ maxmsglen = PQ_SMALL_MESSAGE_LIMIT; /* stop any active skip-till-Sync */ ignore_till_sync = false; /* mark not-extended, so that a new error doesn't begin skip */ doing_extended_query_message = false; break; case 'd': /* copy data */ maxmsglen = PQ_LARGE_MESSAGE_LIMIT; doing_extended_query_message = false; break; case 'c': /* copy done */ case 'f': /* copy fail */ maxmsglen = PQ_SMALL_MESSAGE_LIMIT; doing_extended_query_message = false; break; default: /* * Otherwise we got garbage from the frontend. We treat this as * fatal because we have probably lost message boundary sync, and * there's no good way to recover. */ ereport(FATAL, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("invalid frontend message type %d", qtype))); maxmsglen = 0; /* keep compiler quiet */ break; } /* * In protocol version 3, all frontend messages have a length word next * after the type code; we can read the message contents independently of * the type. */ if (pq_getmessage(inBuf, maxmsglen)) return EOF; /* suitable message already logged */ RESUME_CANCEL_INTERRUPTS(); return qtype; } /* ---------------- * ReadCommand reads a command from either the frontend or * standard input, places it in inBuf, and returns the * message type code (first byte of the message). * EOF is returned if end of file. * ---------------- */ static int ReadCommand(StringInfo inBuf) { int result; if (whereToSendOutput == DestRemote) result = SocketBackend(inBuf); else result = InteractiveBackend(inBuf); return result; } /* * ProcessClientReadInterrupt() - Process interrupts specific to client reads * * This is called just before and after low-level reads. * 'blocked' is true if no data was available to read and we plan to retry, * false if about to read or done reading. * * Must preserve errno! */ void ProcessClientReadInterrupt(bool blocked) { 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; } /* * ProcessClientWriteInterrupt() - Process interrupts specific to client writes * * This is called just before and after low-level writes. * 'blocked' is true if no data could be written and we plan to retry, * false if about to write or done writing. * * Must preserve errno! */ void ProcessClientWriteInterrupt(bool blocked) { 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; } /* * Do raw parsing (only). * * A list of parsetrees (RawStmt nodes) is returned, since there might be * multiple commands in the given string. * * NOTE: for interactive queries, it is important to keep this routine * separate from the analysis & rewrite stages. Analysis and rewriting * cannot be done in an aborted transaction, since they require access to * database tables. So, we rely on the raw parser to determine whether * we've seen a COMMIT or ABORT command; when we are in abort state, other * commands are not processed any further than the raw parse stage. */ List * pg_parse_query(const char *query_string) { 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 COPY_PARSE_PLAN_TREES /* Optional debugging check: pass raw parsetrees through copyObject() */ { 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; } #endif /* * Currently, outfuncs/readfuncs support is missing for many raw parse * tree nodes, so we don't try to implement WRITE_READ_PARSE_PLAN_TREES * here. */ TRACE_POSTGRESQL_QUERY_PARSE_DONE(query_string); return raw_parsetree_list; } /* * Given a raw parsetree (gram.y output), and optionally information about * types of parameter symbols ($n), perform parse analysis and rule rewriting. * * A list of Query nodes is returned, since either the analyzer or the * rewriter might expand one query to several. * * NOTE: for reasons mentioned above, this must be separate from raw parsing. */ List * pg_analyze_and_rewrite(RawStmt *parsetree, const char *query_string, Oid *paramTypes, int numParams, QueryEnvironment *queryEnv) { Query *query; List *querytree_list; TRACE_POSTGRESQL_QUERY_REWRITE_START(query_string); /* * (1) Perform parse analysis. */ if (log_parser_stats) ResetUsage(); query = parse_analyze(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; } /* * Do parse analysis and rewriting. This is the same as pg_analyze_and_rewrite * except that external-parameter resolution is determined by parser callback * hooks instead of a fixed list of parameter datatypes. */ List * pg_analyze_and_rewrite_params(RawStmt *parsetree, const char *query_string, ParserSetupHook parserSetup, void *parserSetupArg, QueryEnvironment *queryEnv) { ParseState *pstate; Query *query; List *querytree_list; JumbleState *jstate = NULL; Assert(query_string != NULL); /* required as of 8.4 */ TRACE_POSTGRESQL_QUERY_REWRITE_START(query_string); /* * (1) Perform parse analysis. */ if (log_parser_stats) ResetUsage(); pstate = make_parsestate(NULL); pstate->p_sourcetext = query_string; pstate->p_queryEnv = queryEnv; (*parserSetup) (pstate, parserSetupArg); query = transformTopLevelStmt(pstate, parsetree); if (IsQueryIdEnabled()) jstate = JumbleQuery(query, query_string); if (post_parse_analyze_hook) (*post_parse_analyze_hook) (pstate, query, jstate); free_parsestate(pstate); pgstat_report_query_id(query->queryId, false); 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; } /* * Perform rewriting of a query produced by parse analysis. * * Note: query must just have come from the parser, because we do not do * AcquireRewriteLocks() on it. */ List * pg_rewrite_query(Query *query) { 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 COPY_PARSE_PLAN_TREES /* Optional debugging check: pass querytree through copyObject() */ { 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 equal parse tree"); else querytree_list = new_list; } #endif #ifdef WRITE_READ_PARSE_PLAN_TREES /* Optional debugging check: pass querytree through outfuncs/readfuncs */ { List *new_list = NIL; ListCell *lc; /* * We currently lack outfuncs/readfuncs support for most utility * statement types, so only attempt to write/read non-utility queries. */ foreach(lc, querytree_list) { Query *query = castNode(Query, lfirst(lc)); if (query->commandType != CMD_UTILITY) { char *str = nodeToString(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 = query->queryId; new_list = lappend(new_list, new_query); pfree(str); } else new_list = lappend(new_list, query); } /* This checks both outfuncs/readfuncs and the equal() routines... */ if (!equal(new_list, querytree_list)) elog(WARNING, "outfuncs/readfuncs failed to produce equal parse tree"); else querytree_list = new_list; } #endif if (Debug_print_rewritten) elog_node_display(LOG, "rewritten parse tree", querytree_list, Debug_pretty_print); return querytree_list; } /* * Generate a plan for a single already-rewritten query. * This is a thin wrapper around planner() and takes the same parameters. */ PlannedStmt * pg_plan_query(Query *querytree, const char *query_string, int cursorOptions, ParamListInfo boundParams) { 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 COPY_PARSE_PLAN_TREES /* Optional debugging check: pass plan tree through copyObject() */ { 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; } #endif #ifdef WRITE_READ_PARSE_PLAN_TREES /* Optional debugging check: pass plan tree through outfuncs/readfuncs */ { char *str; PlannedStmt *new_plan; str = nodeToString(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 /* * Print plan if debugging. */ if (Debug_print_plan) elog_node_display(LOG, "plan", plan, Debug_pretty_print); TRACE_POSTGRESQL_QUERY_PLAN_DONE(); return plan; } /* * Generate plans for a list of already-rewritten queries. * * For normal optimizable statements, invoke the planner. For utility * statements, just make a wrapper PlannedStmt node. * * The result is a list of PlannedStmt nodes. */ List * pg_plan_queries(List *querytrees, const char *query_string, int cursorOptions, ParamListInfo boundParams) { 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; } /* * exec_simple_query * * Execute a "simple Query" protocol message. */ static void exec_simple_query(const char *query_string) { CommandDest dest = whereToSendOutput; MemoryContext oldcontext; List *parsetree_list; ListCell *parsetree_item; bool save_log_statement_stats = log_statement_stats; bool was_logged = false; bool use_implicit_block; char msec_str[32]; /* * Report query to various monitoring facilities. */ debug_query_string = query_string; pgstat_report_activity(STATE_RUNNING, query_string); TRACE_POSTGRESQL_QUERY_START(query_string); /* * We use save_log_statement_stats so ShowUsage doesn't report incorrect * results because ResetUsage wasn't called. */ if (save_log_statement_stats) ResetUsage(); /* * Start up a transaction command. All queries generated by the * query_string will be in this same command block, *unless* we find a * BEGIN/COMMIT/ABORT statement; we have to force a new xact command after * one of those, else bad things will happen in xact.c. (Note that this * will normally change current memory context.) */ start_xact_command(); /* * Zap any pre-existing unnamed statement. (While not strictly necessary, * it seems best to define simple-Query mode as if it used the unnamed * statement and portal; this ensures we recover any storage used by prior * unnamed operations.) */ drop_unnamed_stmt(); /* * Switch to appropriate context for constructing parsetrees. */ oldcontext = MemoryContextSwitchTo(MessageContext); /* * Do basic parsing of the query or queries (this should be safe even if * we are in aborted transaction state!) */ parsetree_list = pg_parse_query(query_string); /* Log immediately if dictated by log_statement */ if (check_log_statement(parsetree_list)) { ereport(LOG, (errmsg("statement: %s", query_string), errhidestmt(true), errdetail_execute(parsetree_list))); was_logged = true; } /* * Switch back to transaction context to enter the loop. */ MemoryContextSwitchTo(oldcontext); /* * For historical reasons, if multiple SQL statements are given in a * single "simple Query" message, we execute them as a single transaction, * unless explicit transaction control commands are included to make * portions of the list be separate transactions. To represent this * behavior properly in the transaction machinery, we use an "implicit" * transaction block. */ use_implicit_block = (list_length(parsetree_list) > 1); /* * Run through the raw parsetree(s) and process each one. */ foreach(parsetree_item, parsetree_list) { RawStmt *parsetree = lfirst_node(RawStmt, parsetree_item); bool snapshot_set = false; CommandTag commandTag; QueryCompletion qc; MemoryContext per_parsetree_context = NULL; List *querytree_list, *plantree_list; Portal portal; DestReceiver *receiver; int16 format; pgstat_report_query_id(0, true); /* * Get the command name for use in status display (it also becomes the * default completion tag, down inside PortalRun). Set ps_status and * do any special start-of-SQL-command processing needed by the * destination. */ commandTag = CreateCommandTag(parsetree->stmt); set_ps_display(GetCommandTagName(commandTag)); BeginCommand(commandTag, dest); /* * If we are in an aborted transaction, reject all commands except * COMMIT/ABORT. It is important that this test occur before we try * to do parse analysis, rewrite, or planning, since all those phases * try to do database accesses, which may fail in abort state. (It * might be safe to allow some additional utility commands in this * state, but not many...) */ if (IsAbortedTransactionBlockState() && !IsTransactionExitStmt(parsetree->stmt)) ereport(ERROR, (errcode(ERRCODE_IN_FAILED_SQL_TRANSACTION), errmsg("current transaction is aborted, " "commands ignored until end of transaction block"), errdetail_abort())); /* Make sure we are in a transaction command */ start_xact_command(); /* * If using an implicit transaction block, and we're not already in a * transaction block, start an implicit block to force this statement * to be grouped together with any following ones. (We must do this * each time through the loop; otherwise, a COMMIT/ROLLBACK in the * list would cause later statements to not be grouped.) */ if (use_implicit_block) BeginImplicitTransactionBlock(); /* If we got a cancel signal in parsing or prior command, quit */ CHECK_FOR_INTERRUPTS(); /* * Set up a snapshot if parse analysis/planning will need one. */ if (analyze_requires_snapshot(parsetree)) { PushActiveSnapshot(GetTransactionSnapshot()); snapshot_set = true; } /* * OK to analyze, rewrite, and plan this query. * * Switch to appropriate context for constructing query and plan trees * (these can't be in the transaction context, as that will get reset * when the command is COMMIT/ROLLBACK). If we have multiple * parsetrees, we use a separate context for each one, so that we can * free that memory before moving on to the next one. But for the * last (or only) parsetree, just use MessageContext, which will be * reset shortly after completion anyway. In event of an error, the * per_parsetree_context will be deleted when MessageContext is reset. */ if (lnext(parsetree_list, parsetree_item) != NULL) { per_parsetree_context = AllocSetContextCreate(MessageContext, "per-parsetree message context", ALLOCSET_DEFAULT_SIZES); oldcontext = MemoryContextSwitchTo(per_parsetree_context); } else oldcontext = MemoryContextSwitchTo(MessageContext); querytree_list = pg_analyze_and_rewrite(parsetree, query_string, NULL, 0, NULL); plantree_list = pg_plan_queries(querytree_list, query_string, CURSOR_OPT_PARALLEL_OK, NULL); /* * Done with the snapshot used for parsing/planning. * * While it looks promising to reuse the same snapshot for query * execution (at least for simple protocol), unfortunately it causes * execution to use a snapshot that has been acquired before locking * any of the tables mentioned in the query. This creates user- * visible anomalies, so refrain. Refer to * https://postgr.es/m/flat/5075D8DF.6050500@fuzzy.cz for details. */ if (snapshot_set) PopActiveSnapshot(); /* If we got a cancel signal in analysis or planning, quit */ CHECK_FOR_INTERRUPTS(); /* * Create unnamed portal to run the query or queries in. If there * already is one, silently drop it. */ portal = CreatePortal("", true, true); /* Don't display the portal in pg_cursors */ portal->visible = false; /* * We don't have to copy anything into the portal, because everything * we are passing here is in MessageContext or the * per_parsetree_context, and so will outlive the portal anyway. */ PortalDefineQuery(portal, NULL, query_string, commandTag, plantree_list, NULL); /* * Start the portal. No parameters here. */ PortalStart(portal, NULL, 0, InvalidSnapshot); /* * Select the appropriate output format: text unless we are doing a * FETCH from a binary cursor. (Pretty grotty to have to do this here * --- but it avoids grottiness in other places. Ah, the joys of * backward compatibility...) */ format = 0; /* TEXT is default */ if (IsA(parsetree->stmt, FetchStmt)) { FetchStmt *stmt = (FetchStmt *) parsetree->stmt; if (!stmt->ismove) { Portal fportal = GetPortalByName(stmt->portalname); if (PortalIsValid(fportal) && (fportal->cursorOptions & CURSOR_OPT_BINARY)) format = 1; /* BINARY */ } } PortalSetResultFormat(portal, 1, &format); /* * Now we can create the destination receiver object. */ receiver = CreateDestReceiver(dest); if (dest == DestRemote) SetRemoteDestReceiverParams(receiver, portal); /* * Switch back to transaction context for execution. */ MemoryContextSwitchTo(oldcontext); /* * Run the portal to completion, and then drop it (and the receiver). */ (void) PortalRun(portal, FETCH_ALL, true, /* always top level */ true, receiver, receiver, &qc); receiver->rDestroy(receiver); PortalDrop(portal, false); if (lnext(parsetree_list, parsetree_item) == NULL) { /* * If this is the last parsetree of the query string, close down * transaction statement before reporting command-complete. This * is so that any end-of-transaction errors are reported before * the command-complete message is issued, to avoid confusing * clients who will expect either a command-complete message or an * error, not one and then the other. Also, if we're using an * implicit transaction block, we must close that out first. */ if (use_implicit_block) EndImplicitTransactionBlock(); finish_xact_command(); } else if (IsA(parsetree->stmt, TransactionStmt)) { /* * If this was a transaction control statement, commit it. We will * start a new xact command for the next command. */ finish_xact_command(); } else { /* * We had better not see XACT_FLAGS_NEEDIMMEDIATECOMMIT set if * we're not calling finish_xact_command(). (The implicit * transaction block should have prevented it from getting set.) */ Assert(!(MyXactFlags & XACT_FLAGS_NEEDIMMEDIATECOMMIT)); /* * We need a CommandCounterIncrement after every query, except * those that start or end a transaction block. */ CommandCounterIncrement(); /* * Disable statement timeout between queries of a multi-query * string, so that the timeout applies separately to each query. * (Our next loop iteration will start a fresh timeout.) */ disable_statement_timeout(); } /* * Tell client that we're done with this query. Note we emit exactly * one EndCommand report for each raw parsetree, thus one for each SQL * command the client sent, regardless of rewriting. (But a command * aborted by error will not send an EndCommand report at all.) */ EndCommand(&qc, dest, false); /* Now we may drop the per-parsetree context, if one was created. */ if (per_parsetree_context) MemoryContextDelete(per_parsetree_context); } /* end loop over parsetrees */ /* * Close down transaction statement, if one is open. (This will only do * something if the parsetree list was empty; otherwise the last loop * iteration already did it.) */ finish_xact_command(); /* * If there were no parsetrees, return EmptyQueryResponse message. */ if (!parsetree_list) NullCommand(dest); /* * Emit duration logging if appropriate. */ switch (check_log_duration(msec_str, was_logged)) { case 1: ereport(LOG, (errmsg("duration: %s ms", msec_str), errhidestmt(true))); break; case 2: ereport(LOG, (errmsg("duration: %s ms statement: %s", msec_str, query_string), errhidestmt(true), errdetail_execute(parsetree_list))); break; } if (save_log_statement_stats) ShowUsage("QUERY STATISTICS"); TRACE_POSTGRESQL_QUERY_DONE(query_string); debug_query_string = NULL; } /* * exec_parse_message * * Execute a "Parse" protocol message. */ static void exec_parse_message(const char *query_string, /* string to execute */ const char *stmt_name, /* name for prepared stmt */ Oid *paramTypes, /* parameter types */ int numParams) /* number of parameters */ { MemoryContext unnamed_stmt_context = NULL; MemoryContext oldcontext; List *parsetree_list; RawStmt *raw_parse_tree; List *querytree_list; CachedPlanSource *psrc; bool is_named; bool save_log_statement_stats = log_statement_stats; char msec_str[32]; /* * Report query to various monitoring facilities. */ debug_query_string = query_string; pgstat_report_activity(STATE_RUNNING, query_string); set_ps_display("PARSE"); if (save_log_statement_stats) ResetUsage(); ereport(DEBUG2, (errmsg_internal("parse %s: %s", *stmt_name ? stmt_name : "", query_string))); /* * Start up a transaction command so we can run parse analysis etc. (Note * that this will normally change current memory context.) Nothing happens * if we are already in one. This also arms the statement timeout if * necessary. */ start_xact_command(); /* * Switch to appropriate context for constructing parsetrees. * * We have two strategies depending on whether the prepared statement is * named or not. For a named prepared statement, we do parsing in * MessageContext and copy the finished trees into the prepared * statement's plancache entry; then the reset of MessageContext releases * temporary space used by parsing and rewriting. For an unnamed prepared * statement, we assume the statement isn't going to hang around long, so * getting rid of temp space quickly is probably not worth the costs of * copying parse trees. So in this case, we create the plancache entry's * query_context here, and do all the parsing work therein. */ is_named = (stmt_name[0] != '\0'); if (is_named) { /* Named prepared statement --- parse in MessageContext */ oldcontext = MemoryContextSwitchTo(MessageContext); } else { /* Unnamed prepared statement --- release any prior unnamed stmt */ drop_unnamed_stmt(); /* Create context for parsing */ unnamed_stmt_context = AllocSetContextCreate(MessageContext, "unnamed prepared statement", ALLOCSET_DEFAULT_SIZES); oldcontext = MemoryContextSwitchTo(unnamed_stmt_context); } /* * Do basic parsing of the query or queries (this should be safe even if * we are in aborted transaction state!) */ parsetree_list = pg_parse_query(query_string); /* * We only allow a single user statement in a prepared statement. This is * mainly to keep the protocol simple --- otherwise we'd need to worry * about multiple result tupdescs and things like that. */ if (list_length(parsetree_list) > 1) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("cannot insert multiple commands into a prepared statement"))); if (parsetree_list != NIL) { Query *query; bool snapshot_set = false; raw_parse_tree = linitial_node(RawStmt, parsetree_list); /* * If we are in an aborted transaction, reject all commands except * COMMIT/ROLLBACK. It is important that this test occur before we * try to do parse analysis, rewrite, or planning, since all those * phases try to do database accesses, which may fail in abort state. * (It might be safe to allow some additional utility commands in this * state, but not many...) */ if (IsAbortedTransactionBlockState() && !IsTransactionExitStmt(raw_parse_tree->stmt)) ereport(ERROR, (errcode(ERRCODE_IN_FAILED_SQL_TRANSACTION), errmsg("current transaction is aborted, " "commands ignored until end of transaction block"), errdetail_abort())); /* * Create the CachedPlanSource before we do parse analysis, since it * needs to see the unmodified raw parse tree. */ psrc = CreateCachedPlan(raw_parse_tree, query_string, CreateCommandTag(raw_parse_tree->stmt)); /* * Set up a snapshot if parse analysis will need one. */ if (analyze_requires_snapshot(raw_parse_tree)) { PushActiveSnapshot(GetTransactionSnapshot()); snapshot_set = true; } /* * Analyze and rewrite the query. Note that the originally specified * parameter set is not required to be complete, so we have to use * parse_analyze_varparams(). */ if (log_parser_stats) ResetUsage(); query = parse_analyze_varparams(raw_parse_tree, query_string, ¶mTypes, &numParams); /* * 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"); querytree_list = pg_rewrite_query(query); /* Done with the snapshot used for parsing */ if (snapshot_set) PopActiveSnapshot(); } else { /* Empty input string. This is legal. */ raw_parse_tree = NULL; psrc = CreateCachedPlan(raw_parse_tree, query_string, CMDTAG_UNKNOWN); querytree_list = NIL; } /* * CachedPlanSource must be a direct child of MessageContext before we * reparent unnamed_stmt_context under it, else we have a disconnected * circular subgraph. Klugy, but less so than flipping contexts even more * above. */ if (unnamed_stmt_context) MemoryContextSetParent(psrc->context, MessageContext); /* Finish filling in the CachedPlanSource */ CompleteCachedPlan(psrc, querytree_list, unnamed_stmt_context, paramTypes, numParams, NULL, NULL, CURSOR_OPT_PARALLEL_OK, /* allow parallel mode */ true); /* fixed result */ /* If we got a cancel signal during analysis, quit */ CHECK_FOR_INTERRUPTS(); if (is_named) { /* * Store the query as a prepared statement. */ StorePreparedStatement(stmt_name, psrc, false); } else { /* * We just save the CachedPlanSource into unnamed_stmt_psrc. */ SaveCachedPlan(psrc); unnamed_stmt_psrc = psrc; } MemoryContextSwitchTo(oldcontext); /* * We do NOT close the open transaction command here; that only happens * when the client sends Sync. Instead, do CommandCounterIncrement just * in case something happened during parse/plan. */ CommandCounterIncrement(); /* * Send ParseComplete. */ if (whereToSendOutput == DestRemote) pq_putemptymessage('1'); /* * Emit duration logging if appropriate. */ switch (check_log_duration(msec_str, false)) { case 1: ereport(LOG, (errmsg("duration: %s ms", msec_str), errhidestmt(true))); break; case 2: ereport(LOG, (errmsg("duration: %s ms parse %s: %s", msec_str, *stmt_name ? stmt_name : "", query_string), errhidestmt(true))); break; } if (save_log_statement_stats) ShowUsage("PARSE MESSAGE STATISTICS"); debug_query_string = NULL; } /* * exec_bind_message * * Process a "Bind" message to create a portal from a prepared statement */ static void exec_bind_message(StringInfo input_message) { const char *portal_name; const char *stmt_name; int numPFormats; int16 *pformats = NULL; int numParams; int numRFormats; int16 *rformats = NULL; CachedPlanSource *psrc; CachedPlan *cplan; Portal portal; char *query_string; char *saved_stmt_name; ParamListInfo params; MemoryContext oldContext; bool save_log_statement_stats = log_statement_stats; bool snapshot_set = false; char msec_str[32]; ParamsErrorCbData params_data; ErrorContextCallback params_errcxt; /* Get the fixed part of the message */ portal_name = pq_getmsgstring(input_message); stmt_name = pq_getmsgstring(input_message); ereport(DEBUG2, (errmsg_internal("bind %s to %s", *portal_name ? portal_name : "", *stmt_name ? stmt_name : ""))); /* Find prepared statement */ if (stmt_name[0] != '\0') { PreparedStatement *pstmt; pstmt = FetchPreparedStatement(stmt_name, true); psrc = pstmt->plansource; } else { /* special-case the unnamed statement */ psrc = unnamed_stmt_psrc; if (!psrc) ereport(ERROR, (errcode(ERRCODE_UNDEFINED_PSTATEMENT), errmsg("unnamed prepared statement does not exist"))); } /* * Report query to various monitoring facilities. */ debug_query_string = psrc->query_string; pgstat_report_activity(STATE_RUNNING, psrc->query_string); set_ps_display("BIND"); if (save_log_statement_stats) ResetUsage(); /* * Start up a transaction command so we can call functions etc. (Note that * this will normally change current memory context.) Nothing happens if * we are already in one. This also arms the statement timeout if * necessary. */ start_xact_command(); /* Switch back to message context */ MemoryContextSwitchTo(MessageContext); /* Get the parameter format codes */ numPFormats = pq_getmsgint(input_message, 2); if (numPFormats > 0) { pformats = (int16 *) palloc(numPFormats * sizeof(int16)); for (int i = 0; i < numPFormats; i++) pformats[i] = pq_getmsgint(input_message, 2); } /* Get the parameter value count */ numParams = pq_getmsgint(input_message, 2); if (numPFormats > 1 && numPFormats != numParams) ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("bind message has %d parameter formats but %d parameters", numPFormats, numParams))); if (numParams != psrc->num_params) ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("bind message supplies %d parameters, but prepared statement \"%s\" requires %d", numParams, stmt_name, psrc->num_params))); /* * If we are in aborted transaction state, the only portals we can * actually run are those containing COMMIT or ROLLBACK commands. We * disallow binding anything else to avoid problems with infrastructure * that expects to run inside a valid transaction. We also disallow * binding any parameters, since we can't risk calling user-defined I/O * functions. */ if (IsAbortedTransactionBlockState() && (!(psrc->raw_parse_tree && IsTransactionExitStmt(psrc->raw_parse_tree->stmt)) || numParams != 0)) ereport(ERROR, (errcode(ERRCODE_IN_FAILED_SQL_TRANSACTION), errmsg("current transaction is aborted, " "commands ignored until end of transaction block"), errdetail_abort())); /* * Create the portal. Allow silent replacement of an existing portal only * if the unnamed portal is specified. */ if (portal_name[0] == '\0') portal = CreatePortal(portal_name, true, true); else portal = CreatePortal(portal_name, false, false); /* * Prepare to copy stuff into the portal's memory context. We do all this * copying first, because it could possibly fail (out-of-memory) and we * don't want a failure to occur between GetCachedPlan and * PortalDefineQuery; that would result in leaking our plancache refcount. */ oldContext = MemoryContextSwitchTo(portal->portalContext); /* Copy the plan's query string into the portal */ query_string = pstrdup(psrc->query_string); /* Likewise make a copy of the statement name, unless it's unnamed */ if (stmt_name[0]) saved_stmt_name = pstrdup(stmt_name); else saved_stmt_name = NULL; /* * Set a snapshot if we have parameters to fetch (since the input * functions might need it) or the query isn't a utility command (and * hence could require redoing parse analysis and planning). We keep the * snapshot active till we're done, so that plancache.c doesn't have to * take new ones. */ if (numParams > 0 || (psrc->raw_parse_tree && analyze_requires_snapshot(psrc->raw_parse_tree))) { PushActiveSnapshot(GetTransactionSnapshot()); snapshot_set = true; } /* * Fetch parameters, if any, and store in the portal's memory context. */ if (numParams > 0) { char **knownTextValues = NULL; /* allocate on first use */ BindParamCbData one_param_data; /* * Set up an error callback so that if there's an error in this phase, * we can report the specific parameter causing the problem. */ one_param_data.portalName = portal->name; one_param_data.paramno = -1; one_param_data.paramval = NULL; params_errcxt.previous = error_context_stack; params_errcxt.callback = bind_param_error_callback; params_errcxt.arg = (void *) &one_param_data; error_context_stack = ¶ms_errcxt; params = makeParamList(numParams); for (int paramno = 0; paramno < numParams; paramno++) { Oid ptype = psrc->param_types[paramno]; int32 plength; Datum pval; bool isNull; StringInfoData pbuf; char csave; int16 pformat; one_param_data.paramno = paramno; one_param_data.paramval = NULL; plength = pq_getmsgint(input_message, 4); isNull = (plength == -1); if (!isNull) { const char *pvalue = pq_getmsgbytes(input_message, plength); /* * Rather than copying data around, we just set up a phony * StringInfo pointing to the correct portion of the message * buffer. We assume we can scribble on the message buffer so * as to maintain the convention that StringInfos have a * trailing null. This is grotty but is a big win when * dealing with very large parameter strings. */ pbuf.data = unconstify(char *, pvalue); pbuf.maxlen = plength + 1; pbuf.len = plength; pbuf.cursor = 0; csave = pbuf.data[plength]; pbuf.data[plength] = '\0'; } else { pbuf.data = NULL; /* keep compiler quiet */ csave = 0; } if (numPFormats > 1) pformat = pformats[paramno]; else if (numPFormats > 0) pformat = pformats[0]; else pformat = 0; /* default = text */ if (pformat == 0) /* text mode */ { Oid typinput; Oid typioparam; char *pstring; getTypeInputInfo(ptype, &typinput, &typioparam); /* * We have to do encoding conversion before calling the * typinput routine. */ if (isNull) pstring = NULL; else pstring = pg_client_to_server(pbuf.data, plength); /* Now we can log the input string in case of error */ one_param_data.paramval = pstring; pval = OidInputFunctionCall(typinput, pstring, typioparam, -1); one_param_data.paramval = NULL; /* * If we might need to log parameters later, save a copy of * the converted string in MessageContext; then free the * result of encoding conversion, if any was done. */ if (pstring) { if (log_parameter_max_length_on_error != 0) { MemoryContext oldcxt; oldcxt = MemoryContextSwitchTo(MessageContext); if (knownTextValues == NULL) knownTextValues = palloc0(numParams * sizeof(char *)); if (log_parameter_max_length_on_error < 0) knownTextValues[paramno] = pstrdup(pstring); else { /* * We can trim the saved string, knowing that we * won't print all of it. But we must copy at * least two more full characters than * BuildParamLogString wants to use; otherwise it * might fail to include the trailing ellipsis. */ knownTextValues[paramno] = pnstrdup(pstring, log_parameter_max_length_on_error + 2 * MAX_MULTIBYTE_CHAR_LEN); } MemoryContextSwitchTo(oldcxt); } if (pstring != pbuf.data) pfree(pstring); } } else if (pformat == 1) /* binary mode */ { Oid typreceive; Oid typioparam; StringInfo bufptr; /* * Call the parameter type's binary input converter */ getTypeBinaryInputInfo(ptype, &typreceive, &typioparam); if (isNull) bufptr = NULL; else bufptr = &pbuf; pval = OidReceiveFunctionCall(typreceive, bufptr, typioparam, -1); /* Trouble if it didn't eat the whole buffer */ if (!isNull && pbuf.cursor != pbuf.len) ereport(ERROR, (errcode(ERRCODE_INVALID_BINARY_REPRESENTATION), errmsg("incorrect binary data format in bind parameter %d", paramno + 1))); } else { ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("unsupported format code: %d", pformat))); pval = 0; /* keep compiler quiet */ } /* Restore message buffer contents */ if (!isNull) pbuf.data[plength] = csave; params->params[paramno].value = pval; params->params[paramno].isnull = isNull; /* * We mark the params as CONST. This ensures that any custom plan * makes full use of the parameter values. */ params->params[paramno].pflags = PARAM_FLAG_CONST; params->params[paramno].ptype = ptype; } /* Pop the per-parameter error callback */ error_context_stack = error_context_stack->previous; /* * Once all parameters have been received, prepare for printing them * in future errors, if configured to do so. (This is saved in the * portal, so that they'll appear when the query is executed later.) */ if (log_parameter_max_length_on_error != 0) params->paramValuesStr = BuildParamLogString(params, knownTextValues, log_parameter_max_length_on_error); } else params = NULL; /* Done storing stuff in portal's context */ MemoryContextSwitchTo(oldContext); /* * Set up another error callback so that all the parameters are logged if * we get an error during the rest of the BIND processing. */ params_data.portalName = portal->name; params_data.params = params; params_errcxt.previous = error_context_stack; params_errcxt.callback = ParamsErrorCallback; params_errcxt.arg = (void *) ¶ms_data; error_context_stack = ¶ms_errcxt; /* Get the result format codes */ numRFormats = pq_getmsgint(input_message, 2); if (numRFormats > 0) { rformats = (int16 *) palloc(numRFormats * sizeof(int16)); for (int i = 0; i < numRFormats; i++) rformats[i] = pq_getmsgint(input_message, 2); } pq_getmsgend(input_message); /* * Obtain a plan from the CachedPlanSource. Any cruft from (re)planning * will be generated in MessageContext. The plan refcount will be * assigned to the Portal, so it will be released at portal destruction. */ cplan = GetCachedPlan(psrc, params, NULL, NULL); /* * Now we can define the portal. * * DO NOT put any code that could possibly throw an error between the * above GetCachedPlan call and here. */ PortalDefineQuery(portal, saved_stmt_name, query_string, psrc->commandTag, cplan->stmt_list, cplan); /* Done with the snapshot used for parameter I/O and parsing/planning */ if (snapshot_set) PopActiveSnapshot(); /* * And we're ready to start portal execution. */ PortalStart(portal, params, 0, InvalidSnapshot); /* * Apply the result format requests to the portal. */ PortalSetResultFormat(portal, numRFormats, rformats); /* * Done binding; remove the parameters error callback. Entries emitted * later determine independently whether to log the parameters or not. */ error_context_stack = error_context_stack->previous; /* * Send BindComplete. */ if (whereToSendOutput == DestRemote) pq_putemptymessage('2'); /* * Emit duration logging if appropriate. */ switch (check_log_duration(msec_str, false)) { case 1: ereport(LOG, (errmsg("duration: %s ms", msec_str), errhidestmt(true))); break; case 2: ereport(LOG, (errmsg("duration: %s ms bind %s%s%s: %s", msec_str, *stmt_name ? stmt_name : "", *portal_name ? "/" : "", *portal_name ? portal_name : "", psrc->query_string), errhidestmt(true), errdetail_params(params))); break; } if (save_log_statement_stats) ShowUsage("BIND MESSAGE STATISTICS"); debug_query_string = NULL; } /* * exec_execute_message * * Process an "Execute" message for a portal */ static void exec_execute_message(const char *portal_name, long max_rows) { CommandDest dest; DestReceiver *receiver; Portal portal; bool completed; QueryCompletion qc; const char *sourceText; const char *prepStmtName; ParamListInfo portalParams; bool save_log_statement_stats = log_statement_stats; bool is_xact_command; bool execute_is_fetch; bool was_logged = false; char msec_str[32]; ParamsErrorCbData params_data; ErrorContextCallback params_errcxt; /* Adjust destination to tell printtup.c what to do */ dest = whereToSendOutput; if (dest == DestRemote) dest = DestRemoteExecute; portal = GetPortalByName(portal_name); if (!PortalIsValid(portal)) ereport(ERROR, (errcode(ERRCODE_UNDEFINED_CURSOR), errmsg("portal \"%s\" does not exist", portal_name))); /* * If the original query was a null string, just return * EmptyQueryResponse. */ if (portal->commandTag == CMDTAG_UNKNOWN) { Assert(portal->stmts == NIL); NullCommand(dest); return; } /* Does the portal contain a transaction command? */ is_xact_command = IsTransactionStmtList(portal->stmts); /* * We must copy the sourceText and prepStmtName into MessageContext in * case the portal is destroyed during finish_xact_command. We do not * make a copy of the portalParams though, preferring to just not print * them in that case. */ sourceText = pstrdup(portal->sourceText); if (portal->prepStmtName) prepStmtName = pstrdup(portal->prepStmtName); else prepStmtName = ""; portalParams = portal->portalParams; /* * Report query to various monitoring facilities. */ debug_query_string = sourceText; pgstat_report_activity(STATE_RUNNING, sourceText); set_ps_display(GetCommandTagName(portal->commandTag)); if (save_log_statement_stats) ResetUsage(); BeginCommand(portal->commandTag, dest); /* * Create dest receiver in MessageContext (we don't want it in transaction * context, because that may get deleted if portal contains VACUUM). */ receiver = CreateDestReceiver(dest); if (dest == DestRemoteExecute) SetRemoteDestReceiverParams(receiver, portal); /* * Ensure we are in a transaction command (this should normally be the * case already due to prior BIND). */ start_xact_command(); /* * If we re-issue an Execute protocol request against an existing portal, * then we are only fetching more rows rather than completely re-executing * the query from the start. atStart is never reset for a v3 portal, so we * are safe to use this check. */ execute_is_fetch = !portal->atStart; /* Log immediately if dictated by log_statement */ if (check_log_statement(portal->stmts)) { ereport(LOG, (errmsg("%s %s%s%s: %s", execute_is_fetch ? _("execute fetch from") : _("execute"), prepStmtName, *portal_name ? "/" : "", *portal_name ? portal_name : "", sourceText), errhidestmt(true), errdetail_params(portalParams))); was_logged = true; } /* * If we are in aborted transaction state, the only portals we can * actually run are those containing COMMIT or ROLLBACK commands. */ if (IsAbortedTransactionBlockState() && !IsTransactionExitStmtList(portal->stmts)) ereport(ERROR, (errcode(ERRCODE_IN_FAILED_SQL_TRANSACTION), errmsg("current transaction is aborted, " "commands ignored until end of transaction block"), errdetail_abort())); /* Check for cancel signal before we start execution */ CHECK_FOR_INTERRUPTS(); /* * Okay to run the portal. Set the error callback so that parameters are * logged. The parameters must have been saved during the bind phase. */ params_data.portalName = portal->name; params_data.params = portalParams; params_errcxt.previous = error_context_stack; params_errcxt.callback = ParamsErrorCallback; params_errcxt.arg = (void *) ¶ms_data; error_context_stack = ¶ms_errcxt; if (max_rows <= 0) max_rows = FETCH_ALL; completed = PortalRun(portal, max_rows, true, /* always top level */ !execute_is_fetch && max_rows == FETCH_ALL, receiver, receiver, &qc); receiver->rDestroy(receiver); /* Done executing; remove the params error callback */ error_context_stack = error_context_stack->previous; if (completed) { if (is_xact_command || (MyXactFlags & XACT_FLAGS_NEEDIMMEDIATECOMMIT)) { /* * If this was a transaction control statement, commit it. We * will start a new xact command for the next command (if any). * Likewise if the statement required immediate commit. Without * this provision, we wouldn't force commit until Sync is * received, which creates a hazard if the client tries to * pipeline immediate-commit statements. */ finish_xact_command(); /* * These commands typically don't have any parameters, and even if * one did we couldn't print them now because the storage went * away during finish_xact_command. So pretend there were none. */ portalParams = NULL; } else { /* * We need a CommandCounterIncrement after every query, except * those that start or end a transaction block. */ CommandCounterIncrement(); /* * Disable statement timeout whenever we complete an Execute * message. The next protocol message will start a fresh timeout. */ disable_statement_timeout(); } /* Send appropriate CommandComplete to client */ EndCommand(&qc, dest, false); } else { /* Portal run not complete, so send PortalSuspended */ if (whereToSendOutput == DestRemote) pq_putemptymessage('s'); } /* * Emit duration logging if appropriate. */ switch (check_log_duration(msec_str, was_logged)) { case 1: ereport(LOG, (errmsg("duration: %s ms", msec_str), errhidestmt(true))); break; case 2: ereport(LOG, (errmsg("duration: %s ms %s %s%s%s: %s", msec_str, execute_is_fetch ? _("execute fetch from") : _("execute"), prepStmtName, *portal_name ? "/" : "", *portal_name ? portal_name : "", sourceText), errhidestmt(true), errdetail_params(portalParams))); break; } if (save_log_statement_stats) ShowUsage("EXECUTE MESSAGE STATISTICS"); debug_query_string = NULL; } /* * check_log_statement * Determine whether command should be logged because of log_statement * * stmt_list can be either raw grammar output or a list of planned * statements */ static bool check_log_statement(List *stmt_list) { ListCell *stmt_item; if (log_statement == LOGSTMT_NONE) return false; if (log_statement == LOGSTMT_ALL) return true; /* Else we have to inspect the statement(s) to see whether to log */ foreach(stmt_item, stmt_list) { Node *stmt = (Node *) lfirst(stmt_item); if (GetCommandLogLevel(stmt) <= log_statement) return true; } return false; } /* * check_log_duration * Determine whether current command's duration should be logged * We also check if this statement in this transaction must be logged * (regardless of its duration). * * Returns: * 0 if no logging is needed * 1 if just the duration should be logged * 2 if duration and query details should be logged * * If logging is needed, the duration in msec is formatted into msec_str[], * which must be a 32-byte buffer. * * was_logged should be true if caller already logged query details (this * essentially prevents 2 from being returned). */ int check_log_duration(char *msec_str, bool was_logged) { 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 random() call * if log_statement_sample_rate = 1. */ if (exceeded_sample_duration) in_sample = log_statement_sample_rate != 0 && (log_statement_sample_rate == 1 || random() <= log_statement_sample_rate * MAX_RANDOM_VALUE); 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; } /* * errdetail_execute * * Add an errdetail() line showing the query referenced by an EXECUTE, if any. * The argument is the raw parsetree list. */ static int errdetail_execute(List *raw_parsetree_list) { ListCell *parsetree_item; foreach(parsetree_item, raw_parsetree_list) { RawStmt *parsetree = lfirst_node(RawStmt, parsetree_item); if (IsA(parsetree->stmt, ExecuteStmt)) { ExecuteStmt *stmt = (ExecuteStmt *) parsetree->stmt; PreparedStatement *pstmt; pstmt = FetchPreparedStatement(stmt->name, false); if (pstmt) { errdetail("prepare: %s", pstmt->plansource->query_string); return 0; } } } return 0; } /* * errdetail_params * * Add an errdetail() line showing bind-parameter data, if available. * Note that this is only used for statement logging, so it is controlled * by log_parameter_max_length not log_parameter_max_length_on_error. */ static int errdetail_params(ParamListInfo params) { if (params && params->numParams > 0 && log_parameter_max_length != 0) { char *str; str = BuildParamLogString(params, NULL, log_parameter_max_length); if (str && str[0] != '\0') errdetail("parameters: %s", str); } return 0; } /* * errdetail_abort * * Add an errdetail() line showing abort reason, if any. */ static int errdetail_abort(void) { if (MyProc->recoveryConflictPending) errdetail("abort reason: recovery conflict"); return 0; } /* * errdetail_recovery_conflict * * Add an errdetail() line showing conflict source. */ static int errdetail_recovery_conflict(void) { switch (RecoveryConflictReason) { case PROCSIG_RECOVERY_CONFLICT_BUFFERPIN: errdetail("User was holding shared buffer pin for too long."); break; case PROCSIG_RECOVERY_CONFLICT_LOCK: errdetail("User was holding a relation lock for too long."); break; case PROCSIG_RECOVERY_CONFLICT_TABLESPACE: errdetail("User was or might have been using tablespace that must be dropped."); break; case PROCSIG_RECOVERY_CONFLICT_SNAPSHOT: errdetail("User query might have needed to see row versions that must be removed."); break; case PROCSIG_RECOVERY_CONFLICT_STARTUP_DEADLOCK: errdetail("User transaction caused buffer deadlock with recovery."); break; case PROCSIG_RECOVERY_CONFLICT_DATABASE: errdetail("User was connected to a database that must be dropped."); break; default: break; /* no errdetail */ } return 0; } /* * bind_param_error_callback * * Error context callback used while parsing parameters in a Bind message */ static void bind_param_error_callback(void *arg) { BindParamCbData *data = (BindParamCbData *) arg; StringInfoData buf; char *quotedval; if (data->paramno < 0) return; /* If we have a textual value, quote it, and trim if necessary */ if (data->paramval) { initStringInfo(&buf); appendStringInfoStringQuoted(&buf, data->paramval, log_parameter_max_length_on_error); quotedval = buf.data; } else quotedval = NULL; if (data->portalName && data->portalName[0] != '\0') { if (quotedval) errcontext("portal \"%s\" parameter $%d = %s", data->portalName, data->paramno + 1, quotedval); else errcontext("portal \"%s\" parameter $%d", data->portalName, data->paramno + 1); } else { if (quotedval) errcontext("unnamed portal parameter $%d = %s", data->paramno + 1, quotedval); else errcontext("unnamed portal parameter $%d", data->paramno + 1); } if (quotedval) pfree(quotedval); } /* * exec_describe_statement_message * * Process a "Describe" message for a prepared statement */ static void exec_describe_statement_message(const char *stmt_name) { CachedPlanSource *psrc; /* * Start up a transaction command. (Note that this will normally change * current memory context.) Nothing happens if we are already in one. */ start_xact_command(); /* Switch back to message context */ MemoryContextSwitchTo(MessageContext); /* Find prepared statement */ if (stmt_name[0] != '\0') { PreparedStatement *pstmt; pstmt = FetchPreparedStatement(stmt_name, true); psrc = pstmt->plansource; } else { /* special-case the unnamed statement */ psrc = unnamed_stmt_psrc; if (!psrc) ereport(ERROR, (errcode(ERRCODE_UNDEFINED_PSTATEMENT), errmsg("unnamed prepared statement does not exist"))); } /* Prepared statements shouldn't have changeable result descs */ Assert(psrc->fixed_result); /* * If we are in aborted transaction state, we can't run * SendRowDescriptionMessage(), because that needs catalog accesses. * Hence, refuse to Describe statements that return data. (We shouldn't * just refuse all Describes, since that might break the ability of some * clients to issue COMMIT or ROLLBACK commands, if they use code that * blindly Describes whatever it does.) We can Describe parameters * without doing anything dangerous, so we don't restrict that. */ if (IsAbortedTransactionBlockState() && psrc->resultDesc) ereport(ERROR, (errcode(ERRCODE_IN_FAILED_SQL_TRANSACTION), errmsg("current transaction is aborted, " "commands ignored until end of transaction block"), errdetail_abort())); if (whereToSendOutput != DestRemote) return; /* can't actually do anything... */ /* * First describe the parameters... */ pq_beginmessage_reuse(&row_description_buf, 't'); /* parameter description * message type */ pq_sendint16(&row_description_buf, psrc->num_params); for (int i = 0; i < psrc->num_params; i++) { Oid ptype = psrc->param_types[i]; pq_sendint32(&row_description_buf, (int) ptype); } pq_endmessage_reuse(&row_description_buf); /* * Next send RowDescription or NoData to describe the result... */ if (psrc->resultDesc) { List *tlist; /* Get the plan's primary targetlist */ tlist = CachedPlanGetTargetList(psrc, NULL); SendRowDescriptionMessage(&row_description_buf, psrc->resultDesc, tlist, NULL); } else pq_putemptymessage('n'); /* NoData */ } /* * exec_describe_portal_message * * Process a "Describe" message for a portal */ static void exec_describe_portal_message(const char *portal_name) { Portal portal; /* * Start up a transaction command. (Note that this will normally change * current memory context.) Nothing happens if we are already in one. */ start_xact_command(); /* Switch back to message context */ MemoryContextSwitchTo(MessageContext); portal = GetPortalByName(portal_name); if (!PortalIsValid(portal)) ereport(ERROR, (errcode(ERRCODE_UNDEFINED_CURSOR), errmsg("portal \"%s\" does not exist", portal_name))); /* * If we are in aborted transaction state, we can't run * SendRowDescriptionMessage(), because that needs catalog accesses. * Hence, refuse to Describe portals that return data. (We shouldn't just * refuse all Describes, since that might break the ability of some * clients to issue COMMIT or ROLLBACK commands, if they use code that * blindly Describes whatever it does.) */ if (IsAbortedTransactionBlockState() && portal->tupDesc) ereport(ERROR, (errcode(ERRCODE_IN_FAILED_SQL_TRANSACTION), errmsg("current transaction is aborted, " "commands ignored until end of transaction block"), errdetail_abort())); if (whereToSendOutput != DestRemote) return; /* can't actually do anything... */ if (portal->tupDesc) SendRowDescriptionMessage(&row_description_buf, portal->tupDesc, FetchPortalTargetList(portal), portal->formats); else pq_putemptymessage('n'); /* NoData */ } /* * Convenience routines for starting/committing a single command. */ static void start_xact_command(void) { if (!xact_started) { StartTransactionCommand(); xact_started = true; } /* * Start statement timeout if necessary. Note that this'll intentionally * not reset the clock on an already started timeout, to avoid the timing * overhead when start_xact_command() is invoked repeatedly, without an * interceding finish_xact_command() (e.g. parse/bind/execute). If that's * not desired, the timeout has to be disabled explicitly. */ enable_statement_timeout(); /* Start timeout for checking if the client has gone away if necessary. */ if (client_connection_check_interval > 0 && IsUnderPostmaster && MyProcPort && !get_timeout_active(CLIENT_CONNECTION_CHECK_TIMEOUT)) enable_timeout_after(CLIENT_CONNECTION_CHECK_TIMEOUT, client_connection_check_interval); } static void finish_xact_command(void) { /* cancel active statement timeout after each command */ disable_statement_timeout(); if (xact_started) { CommitTransactionCommand(); #ifdef MEMORY_CONTEXT_CHECKING /* Check all memory contexts that weren't freed during commit */ /* (those that were, were checked before being deleted) */ MemoryContextCheck(TopMemoryContext); #endif #ifdef SHOW_MEMORY_STATS /* Print mem stats after each commit for leak tracking */ MemoryContextStats(TopMemoryContext); #endif xact_started = false; } } /* * Convenience routines for checking whether a statement is one of the * ones that we allow in transaction-aborted state. */ /* Test a bare parsetree */ static bool IsTransactionExitStmt(Node *parsetree) { if (parsetree && IsA(parsetree, TransactionStmt)) { TransactionStmt *stmt = (TransactionStmt *) parsetree; if (stmt->kind == TRANS_STMT_COMMIT || stmt->kind == TRANS_STMT_PREPARE || stmt->kind == TRANS_STMT_ROLLBACK || stmt->kind == TRANS_STMT_ROLLBACK_TO) return true; } return false; } /* Test a list that contains PlannedStmt nodes */ static bool IsTransactionExitStmtList(List *pstmts) { if (list_length(pstmts) == 1) { PlannedStmt *pstmt = linitial_node(PlannedStmt, pstmts); if (pstmt->commandType == CMD_UTILITY && IsTransactionExitStmt(pstmt->utilityStmt)) return true; } return false; } /* Test a list that contains PlannedStmt nodes */ static bool IsTransactionStmtList(List *pstmts) { if (list_length(pstmts) == 1) { PlannedStmt *pstmt = linitial_node(PlannedStmt, pstmts); if (pstmt->commandType == CMD_UTILITY && IsA(pstmt->utilityStmt, TransactionStmt)) return true; } return false; } /* Release any existing unnamed prepared statement */ static void drop_unnamed_stmt(void) { /* paranoia to avoid a dangling pointer in case of error */ if (unnamed_stmt_psrc) { CachedPlanSource *psrc = unnamed_stmt_psrc; unnamed_stmt_psrc = NULL; DropCachedPlan(psrc); } } /* -------------------------------- * signal handler routines used in PostgresMain() * -------------------------------- */ /* * quickdie() occurs when signaled SIGQUIT by the postmaster. * * Either some backend has bought the farm, or we've been told to shut down * "immediately"; so we need to stop what we're doing and exit. */ void quickdie(SIGNAL_ARGS) { sigaddset(&BlockSig, SIGQUIT); /* prevent nested calls */ PG_SETMASK(&BlockSig); /* * 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); } /* * Shutdown signal from postmaster: abort transaction and exit * at soonest convenient time */ void die(SIGNAL_ARGS) { int save_errno = errno; /* Don't joggle the elbow of proc_exit */ if (!proc_exit_inprogress) { InterruptPending = true; ProcDiePending = true; } /* for the statistics collector */ 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(); errno = save_errno; } /* * Query-cancel signal from postmaster: abort current transaction * at soonest convenient time */ void StatementCancelHandler(SIGNAL_ARGS) { int save_errno = errno; /* * 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); errno = save_errno; } /* signal handler for floating point exception */ void FloatExceptionHandler(SIGNAL_ARGS) { /* 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."))); } /* * RecoveryConflictInterrupt: out-of-line portion of recovery conflict * handling following receipt of SIGUSR1. Designed to be similar to die() * and StatementCancelHandler(). Called only by a normal user backend * that begins a transaction during recovery. */ void RecoveryConflictInterrupt(ProcSignalReason reason) { int save_errno = errno; /* * Don't joggle the elbow of proc_exit */ if (!proc_exit_inprogress) { RecoveryConflictReason = reason; switch (reason) { case PROCSIG_RECOVERY_CONFLICT_STARTUP_DEADLOCK: /* * If we aren't waiting for a lock we can never deadlock. */ if (!IsWaitingForLock()) return; /* Intentional fall through to check wait for pin */ /* FALLTHROUGH */ case PROCSIG_RECOVERY_CONFLICT_BUFFERPIN: /* * If PROCSIG_RECOVERY_CONFLICT_BUFFERPIN is requested but we * aren't blocking the Startup process there is nothing more * to do. * * When PROCSIG_RECOVERY_CONFLICT_STARTUP_DEADLOCK is * requested, if we're waiting for locks and the startup * process is not waiting for buffer pin (i.e., also waiting * for locks), we set the flag so that ProcSleep() will check * for deadlocks. */ if (!HoldingBufferPinThatDelaysRecovery()) { if (reason == PROCSIG_RECOVERY_CONFLICT_STARTUP_DEADLOCK && GetStartupBufferPinWaitBufId() < 0) CheckDeadLockAlert(); return; } MyProc->recoveryConflictPending = true; /* Intentional fall through to error handling */ /* FALLTHROUGH */ case PROCSIG_RECOVERY_CONFLICT_LOCK: case PROCSIG_RECOVERY_CONFLICT_TABLESPACE: case PROCSIG_RECOVERY_CONFLICT_SNAPSHOT: /* * If we aren't in a transaction any longer then ignore. */ if (!IsTransactionOrTransactionBlock()) return; /* * If we can abort just the current subtransaction then we are * OK to throw an ERROR to resolve the conflict. Otherwise * drop through to the FATAL case. * * XXX other times that we can throw just an ERROR *may* be * PROCSIG_RECOVERY_CONFLICT_LOCK if no locks are held in * parent transactions * * PROCSIG_RECOVERY_CONFLICT_SNAPSHOT if no snapshots are held * by parent transactions and the transaction is not * transaction-snapshot mode * * PROCSIG_RECOVERY_CONFLICT_TABLESPACE if no temp files or * cursors open in parent transactions */ if (!IsSubTransaction()) { /* * If we already aborted then we no longer need to cancel. * We do this here since we do not wish to ignore aborted * subtransactions, which must cause FATAL, currently. */ if (IsAbortedTransactionBlockState()) return; RecoveryConflictPending = true; QueryCancelPending = true; InterruptPending = true; break; } /* Intentional fall through to session cancel */ /* FALLTHROUGH */ case PROCSIG_RECOVERY_CONFLICT_DATABASE: RecoveryConflictPending = true; ProcDiePending = true; InterruptPending = true; break; default: elog(FATAL, "unrecognized conflict mode: %d", (int) reason); } Assert(RecoveryConflictPending && (QueryCancelPending || ProcDiePending)); /* * All conflicts apart from database cause dynamic errors where the * command or transaction can be retried at a later point with some * potential for success. No need to reset this, since non-retryable * conflict errors are currently FATAL. */ if (reason == PROCSIG_RECOVERY_CONFLICT_DATABASE) RecoveryConflictRetryable = false; } /* * Set the process latch. This function essentially emulates signal * handlers like die() and StatementCancelHandler() and it seems prudent * to behave similarly as they do. */ SetLatch(MyLatch); errno = save_errno; } /* * ProcessInterrupts: out-of-line portion of CHECK_FOR_INTERRUPTS() macro * * If an interrupt condition is pending, and it's safe to service it, * then clear the flag and accept the interrupt. Called only when * InterruptPending is true. * * Note: if INTERRUPTS_CAN_BE_PROCESSED() is true, then ProcessInterrupts * is guaranteed to clear the InterruptPending flag before returning. * (This is not the same as guaranteeing that it's still clear when we * return; another interrupt could have arrived. But we promise that * any pre-existing one will have been serviced.) */ void ProcessInterrupts(void) { /* OK to accept any interrupts now? */ if (InterruptHoldoffCount != 0 || CritSectionCount != 0) return; InterruptPending = false; if (ProcDiePending) { ProcDiePending = false; QueryCancelPending = false; /* ProcDie trumps QueryCancel */ LockErrorCleanup(); /* As in quickdie, don't risk sending to client during auth */ if (ClientAuthInProgress && whereToSendOutput == DestRemote) whereToSendOutput = DestNone; if (ClientAuthInProgress) ereport(FATAL, (errcode(ERRCODE_QUERY_CANCELED), errmsg("canceling authentication due to timeout"))); else if (IsAutoVacuumWorkerProcess()) ereport(FATAL, (errcode(ERRCODE_ADMIN_SHUTDOWN), errmsg("terminating autovacuum process due to administrator command"))); else if (IsLogicalWorker()) ereport(FATAL, (errcode(ERRCODE_ADMIN_SHUTDOWN), errmsg("terminating logical replication worker due to administrator command"))); else if (IsLogicalLauncher()) { ereport(DEBUG1, (errmsg_internal("logical replication launcher shutting down"))); /* * The logical replication launcher can be stopped at any time. * Use exit status 1 so the background worker is restarted. */ proc_exit(1); } else if (RecoveryConflictPending && RecoveryConflictRetryable) { pgstat_report_recovery_conflict(RecoveryConflictReason); ereport(FATAL, (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE), errmsg("terminating connection due to conflict with recovery"), errdetail_recovery_conflict())); } else if (RecoveryConflictPending) { /* Currently there is only one non-retryable recovery conflict */ Assert(RecoveryConflictReason == PROCSIG_RECOVERY_CONFLICT_DATABASE); pgstat_report_recovery_conflict(RecoveryConflictReason); ereport(FATAL, (errcode(ERRCODE_DATABASE_DROPPED), errmsg("terminating connection due to conflict with recovery"), errdetail_recovery_conflict())); } else if (IsBackgroundWorker) ereport(FATAL, (errcode(ERRCODE_ADMIN_SHUTDOWN), errmsg("terminating background worker \"%s\" due to administrator command", MyBgworkerEntry->bgw_type))); else ereport(FATAL, (errcode(ERRCODE_ADMIN_SHUTDOWN), errmsg("terminating connection due to administrator command"))); } if (CheckClientConnectionPending) { CheckClientConnectionPending = false; /* * Check for lost connection and re-arm, if still configured, but not * if we've arrived back at DoingCommandRead state. We don't want to * wake up idle sessions, and they already know how to detect lost * connections. */ if (!DoingCommandRead && client_connection_check_interval > 0) { if (!pq_check_connection()) ClientConnectionLost = true; else enable_timeout_after(CLIENT_CONNECTION_CHECK_TIMEOUT, client_connection_check_interval); } } if (ClientConnectionLost) { QueryCancelPending = false; /* lost connection trumps QueryCancel */ LockErrorCleanup(); /* don't send to client, we already know the connection to be dead. */ whereToSendOutput = DestNone; ereport(FATAL, (errcode(ERRCODE_CONNECTION_FAILURE), errmsg("connection to client lost"))); } /* * If a recovery conflict happens while we are waiting for input from the * client, the client is presumably just sitting idle in a transaction, * preventing recovery from making progress. Terminate the connection to * dislodge it. */ if (RecoveryConflictPending && DoingCommandRead) { QueryCancelPending = false; /* this trumps QueryCancel */ RecoveryConflictPending = false; LockErrorCleanup(); pgstat_report_recovery_conflict(RecoveryConflictReason); ereport(FATAL, (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE), errmsg("terminating connection due to conflict with recovery"), errdetail_recovery_conflict(), errhint("In a moment you should be able to reconnect to the" " database and repeat your command."))); } /* * Don't allow query cancel interrupts while reading input from the * client, because we might lose sync in the FE/BE protocol. (Die * interrupts are OK, because we won't read any further messages from the * client in that case.) */ if (QueryCancelPending && QueryCancelHoldoffCount != 0) { /* * Re-arm InterruptPending so that we process the cancel request as * soon as we're done reading the message. (XXX this is seriously * ugly: it complicates INTERRUPTS_CAN_BE_PROCESSED(), and it means we * can't use that macro directly as the initial test in this function, * meaning that this code also creates opportunities for other bugs to * appear.) */ InterruptPending = true; } else if (QueryCancelPending) { bool lock_timeout_occurred; bool stmt_timeout_occurred; QueryCancelPending = false; /* * If LOCK_TIMEOUT and STATEMENT_TIMEOUT indicators are both set, we * need to clear both, so always fetch both. */ lock_timeout_occurred = get_timeout_indicator(LOCK_TIMEOUT, true); stmt_timeout_occurred = get_timeout_indicator(STATEMENT_TIMEOUT, true); /* * If both were set, we want to report whichever timeout completed * earlier; this ensures consistent behavior if the machine is slow * enough that the second timeout triggers before we get here. A tie * is arbitrarily broken in favor of reporting a lock timeout. */ if (lock_timeout_occurred && stmt_timeout_occurred && get_timeout_finish_time(STATEMENT_TIMEOUT) < get_timeout_finish_time(LOCK_TIMEOUT)) lock_timeout_occurred = false; /* report stmt timeout */ if (lock_timeout_occurred) { LockErrorCleanup(); ereport(ERROR, (errcode(ERRCODE_LOCK_NOT_AVAILABLE), errmsg("canceling statement due to lock timeout"))); } if (stmt_timeout_occurred) { LockErrorCleanup(); ereport(ERROR, (errcode(ERRCODE_QUERY_CANCELED), errmsg("canceling statement due to statement timeout"))); } if (IsAutoVacuumWorkerProcess()) { LockErrorCleanup(); ereport(ERROR, (errcode(ERRCODE_QUERY_CANCELED), errmsg("canceling autovacuum task"))); } if (RecoveryConflictPending) { RecoveryConflictPending = false; LockErrorCleanup(); pgstat_report_recovery_conflict(RecoveryConflictReason); ereport(ERROR, (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE), errmsg("canceling statement due to conflict with recovery"), errdetail_recovery_conflict())); } /* * If we are reading a command from the client, just ignore the cancel * request --- sending an extra error message won't accomplish * anything. Otherwise, go ahead and throw the error. */ if (!DoingCommandRead) { LockErrorCleanup(); ereport(ERROR, (errcode(ERRCODE_QUERY_CANCELED), errmsg("canceling statement due to user request"))); } } if (IdleInTransactionSessionTimeoutPending) { /* * If the GUC has been reset to zero, ignore the signal. This is * important because the GUC update itself won't disable any pending * interrupt. */ if (IdleInTransactionSessionTimeout > 0) ereport(FATAL, (errcode(ERRCODE_IDLE_IN_TRANSACTION_SESSION_TIMEOUT), errmsg("terminating connection due to idle-in-transaction timeout"))); else IdleInTransactionSessionTimeoutPending = false; } if (IdleSessionTimeoutPending) { /* As above, ignore the signal if the GUC has been reset to zero. */ if (IdleSessionTimeout > 0) ereport(FATAL, (errcode(ERRCODE_IDLE_SESSION_TIMEOUT), errmsg("terminating connection due to idle-session timeout"))); else IdleSessionTimeoutPending = false; } if (ProcSignalBarrierPending) ProcessProcSignalBarrier(); if (ParallelMessagePending) HandleParallelMessages(); if (LogMemoryContextPending) ProcessLogMemoryContextInterrupt(); } /* * IA64-specific code to fetch the AR.BSP register for stack depth checks. * * We currently support gcc, icc, and HP-UX's native compiler here. * * Note: while icc accepts gcc asm blocks on x86[_64], this is not true on * ia64 (at least not in icc versions before 12.x). So we have to carry a * separate implementation for it. */ #if defined(__ia64__) || defined(__ia64) #if defined(__hpux) && !defined(__GNUC__) && !defined(__INTEL_COMPILER) /* Assume it's HP-UX native compiler */ #include #define ia64_get_bsp() ((char *) (_Asm_mov_from_ar(_AREG_BSP, _NO_FENCE))) #elif defined(__INTEL_COMPILER) /* icc */ #include #define ia64_get_bsp() ((char *) __getReg(_IA64_REG_AR_BSP)) #else /* gcc */ static __inline__ char * ia64_get_bsp(void) { char *ret; /* the ;; is a "stop", seems to be required before fetching BSP */ __asm__ __volatile__( ";;\n" " mov %0=ar.bsp \n" : "=r"(ret)); return ret; } #endif #endif /* IA64 */ /* * set_stack_base: set up reference point for stack depth checking * * Returns the old reference point, if any. */ pg_stack_base_t set_stack_base(void) { #ifndef HAVE__BUILTIN_FRAME_ADDRESS char stack_base; #endif pg_stack_base_t old; #if defined(__ia64__) || defined(__ia64) old.stack_base_ptr = stack_base_ptr; old.register_stack_base_ptr = register_stack_base_ptr; #else old = stack_base_ptr; #endif /* * Set up reference point for stack depth checking. On recent gcc we use * __builtin_frame_address() to avoid a warning about storing a local * variable's address in a long-lived variable. */ #ifdef HAVE__BUILTIN_FRAME_ADDRESS stack_base_ptr = __builtin_frame_address(0); #else stack_base_ptr = &stack_base; #endif #if defined(__ia64__) || defined(__ia64) register_stack_base_ptr = ia64_get_bsp(); #endif return old; } /* * restore_stack_base: restore reference point for stack depth checking * * This can be used after set_stack_base() to restore the old value. This * is currently only used in PL/Java. When PL/Java calls a backend function * from different thread, the thread's stack is at a different location than * the main thread's stack, so it sets the base pointer before the call, and * restores it afterwards. */ void restore_stack_base(pg_stack_base_t base) { #if defined(__ia64__) || defined(__ia64) stack_base_ptr = base.stack_base_ptr; register_stack_base_ptr = base.register_stack_base_ptr; #else stack_base_ptr = base; #endif } /* * check_stack_depth/stack_is_too_deep: check for excessively deep recursion * * This should be called someplace in any recursive routine that might possibly * recurse deep enough to overflow the stack. Most Unixen treat stack * overflow as an unrecoverable SIGSEGV, so we want to error out ourselves * before hitting the hardware limit. * * check_stack_depth() just throws an error summarily. stack_is_too_deep() * can be used by code that wants to handle the error condition itself. */ void check_stack_depth(void) { if (stack_is_too_deep()) { ereport(ERROR, (errcode(ERRCODE_STATEMENT_TOO_COMPLEX), errmsg("stack depth limit exceeded"), errhint("Increase the configuration parameter \"max_stack_depth\" (currently %dkB), " "after ensuring the platform's stack depth limit is adequate.", max_stack_depth))); } } bool stack_is_too_deep(void) { char stack_top_loc; long stack_depth; /* * Compute distance from reference point to my local variables */ stack_depth = (long) (stack_base_ptr - &stack_top_loc); /* * Take abs value, since stacks grow up on some machines, down on others */ if (stack_depth < 0) stack_depth = -stack_depth; /* * Trouble? * * The test on stack_base_ptr prevents us from erroring out if called * during process setup or in a non-backend process. Logically it should * be done first, but putting it here avoids wasting cycles during normal * cases. */ if (stack_depth > max_stack_depth_bytes && stack_base_ptr != NULL) return true; /* * On IA64 there is a separate "register" stack that requires its own * independent check. For this, we have to measure the change in the * "BSP" pointer from PostgresMain to here. Logic is just as above, * except that we know IA64's register stack grows up. * * Note we assume that the same max_stack_depth applies to both stacks. */ #if defined(__ia64__) || defined(__ia64) stack_depth = (long) (ia64_get_bsp() - register_stack_base_ptr); if (stack_depth > max_stack_depth_bytes && register_stack_base_ptr != NULL) return true; #endif /* IA64 */ return false; } /* GUC check hook for max_stack_depth */ bool check_max_stack_depth(int *newval, void **extra, GucSource source) { long newval_bytes = *newval * 1024L; long stack_rlimit = get_stack_depth_rlimit(); if (stack_rlimit > 0 && newval_bytes > stack_rlimit - STACK_DEPTH_SLOP) { GUC_check_errdetail("\"max_stack_depth\" must not exceed %ldkB.", (stack_rlimit - STACK_DEPTH_SLOP) / 1024L); GUC_check_errhint("Increase the platform's stack depth limit via \"ulimit -s\" or local equivalent."); return false; } return true; } /* GUC assign hook for max_stack_depth */ void assign_max_stack_depth(int newval, void *extra) { long newval_bytes = newval * 1024L; max_stack_depth_bytes = newval_bytes; } /* * set_debug_options --- apply "-d N" command line option * * -d is not quite the same as setting log_min_messages because it enables * other output options. */ void set_debug_options(int debug_flag, GucContext context, GucSource source) { 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); } bool set_plan_disabling_options(const char *arg, GucContext context, GucSource source) { 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; } const char * get_stats_option_name(const char *arg) { 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; } /* ---------------------------------------------------------------- * process_postgres_switches * Parse command line arguments for PostgresMain * * This is called twice, once for the "secure" options coming from the * postmaster or command line, and once for the "insecure" options coming * from the client's startup packet. The latter have the same syntax but * may be restricted in what they can do. * * argv[0] is ignored in either case (it's assumed to be the program name). * * ctx is PGC_POSTMASTER for secure options, PGC_BACKEND for insecure options * coming from the client, or PGC_SU_BACKEND for insecure options coming from * a superuser client. * * If a database name is present in the command line arguments, it's * returned into *dbname (this is allowed only if *dbname is initially NULL). * ---------------------------------------------------------------- */ void process_postgres_switches(int argc, char *argv[], GucContext ctx, const char **dbname) { 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 '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; 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); free(name); if (value) free(value); 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 } /* ---------------------------------------------------------------- * PostgresMain * postgres main loop -- all backends, interactive or otherwise start here * * argc/argv are the command line arguments to be used. (When being forked * by the postmaster, these are not the original argv array of the process.) * dbname is the name of the database to connect to, or NULL if the database * name should be extracted from the command line arguments or defaulted. * username is the PostgreSQL user name to be used for the session. * ---------------------------------------------------------------- */ void PostgresMain(int argc, char *argv[], const char *dbname, const char *username) { int firstchar; StringInfoData input_message; sigjmp_buf local_sigjmp_buf; volatile bool send_ready_for_query = true; bool idle_in_transaction_timeout_enabled = false; bool idle_session_timeout_enabled = false; /* Initialize startup process environment if necessary. */ if (!IsUnderPostmaster) InitStandaloneProcess(argv[0]); SetProcessingMode(InitProcessing); /* * Set default values for command-line options. */ if (!IsUnderPostmaster) 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, unless inherited from postmaster */ if (!IsUnderPostmaster) { if (!SelectConfigFiles(userDoption, progname)) proc_exit(1); } /* * 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 */ } if (!IsUnderPostmaster) { /* * Validate we have been given a reasonable-looking DataDir (if under * postmaster, assume postmaster did this already). */ checkDataDir(); /* Change into DataDir (if under postmaster, was done already) */ ChangeToDataDir(); /* * Create lockfile for data directory. */ CreateDataDirLockFile(false); /* read control file (error checking and contains config ) */ LocalProcessControlFile(false); /* Initialize MaxBackends (if under postmaster, was done already) */ InitializeMaxBackends(); } /* Early initialization */ BaseInit(); /* * Create a per-backend PGPROC struct in shared memory, except in the * EXEC_BACKEND case where this was done in SubPostmasterMain. We must do * this before we can use LWLocks (and in the EXEC_BACKEND case we already * had to do some stuff with LWLocks). */ #ifdef EXEC_BACKEND if (!IsUnderPostmaster) InitProcess(); #else InitProcess(); #endif /* We need to allow SIGINT, etc during the initial transaction */ PG_SETMASK(&UnBlockSig); /* * 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. */ InitPostgres(dbname, InvalidOid, username, InvalidOid, NULL, false); /* * If the PostmasterContext is still around, recycle the space; we don't * need it anymore after InitPostgres completes. Note this does not trash * *MyProcPort, because ConnCreate() allocated that space with malloc() * ... else we'd need to copy the Port data first. Also, subsidiary data * such as the username isn't lost either; see ProcessStartupPacket(). */ 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(); /* * process any libraries that should be preloaded at backend start (this * likewise can't be done until GUC settings are complete) */ process_session_preload_libraries(); /* * Send this backend's cancellation info to the frontend. */ if (whereToSendOutput == DestRemote) { StringInfoData buf; pq_beginmessage(&buf, 'K'); 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); /* * Remember stand-alone backend startup time */ if (!IsUnderPostmaster) PgStartTime = GetCurrentTimestamp(); /* * 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); QueryCancelPending = false; /* second to avoid race condition */ /* 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(); /* * 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's another cleanup in ProcKill() * ensuring we'll correctly cleanup on FATAL errors as well. */ if (MyReplicationSlot != NULL) ReplicationSlotRelease(); /* We also want to cleanup temporary slots on error. */ ReplicationSlotCleanup(); jit_reset_after_error(); /* * Now return to normal top-level context and clear ErrorContext for * next time. */ MemoryContextSwitchTo(TopMemoryContext); 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 (;;) { /* * 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; /* * Release storage left over from prior query cycle, and create a new * query input buffer in the cleared MessageContext. */ MemoryContextSwitchTo(MessageContext); MemoryContextResetAndDeleteChildren(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 send collected statistics to the * collector, 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) { 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) { idle_in_transaction_timeout_enabled = true; enable_timeout_after(IDLE_IN_TRANSACTION_SESSION_TIMEOUT, IdleInTransactionSessionTimeout); } } else { /* * 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); pgstat_report_stat(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 'Q': /* simple 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); send_ready_for_query = true; } break; case 'P': /* 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 = (Oid *) palloc(numParams * sizeof(Oid)); 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); } break; case 'B': /* 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); break; case 'E': /* 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); } break; case 'F': /* fastpath function call */ forbidden_in_wal_sender(firstchar); /* Set statement_timestamp() */ SetCurrentStatementStartTimestamp(); /* Report query to various monitoring facilities. */ pgstat_report_activity(STATE_FASTPATH, NULL); set_ps_display(""); /* 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(); send_ready_for_query = true; break; case 'C': /* 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('3'); /* CloseComplete */ } break; case 'D': /* 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; } } break; case 'H': /* flush */ pq_getmsgend(&input_message); if (whereToSendOutput == DestRemote) pq_flush(); break; case 'S': /* sync */ pq_getmsgend(&input_message); finish_xact_command(); 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 statistics collector */ pgStatSessionEndCause = DISCONNECT_CLIENT_EOF; /* FALLTHROUGH */ case 'X': /* * 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 'd': /* copy data */ case 'c': /* copy done */ case 'f': /* copy fail */ /* * 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 */ } /* * Throw an error if we're a WAL sender process. * * This is used to forbid anything else than simple query protocol messages * in a WAL sender process. 'firstchar' specifies what kind of a forbidden * message was received, and is used to construct the error message. */ static void forbidden_in_wal_sender(char firstchar) { if (am_walsender) { if (firstchar == 'F') ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("fastpath function calls not supported in a replication connection"))); else ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("extended query protocol not supported in a replication connection"))); } } /* * Obtain platform stack depth limit (in bytes) * * Return -1 if unknown */ long get_stack_depth_rlimit(void) { #if defined(HAVE_GETRLIMIT) && defined(RLIMIT_STACK) 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 /* no getrlimit */ #if defined(WIN32) || defined(__CYGWIN__) /* On Windows we set the backend stack size in src/backend/Makefile */ return WIN32_STACK_RLIMIT; #else /* not windows ... give up */ return -1; #endif #endif } static struct rusage Save_r; static struct timeval Save_t; void ResetUsage(void) { getrusage(RUSAGE_SELF, &Save_r); gettimeofday(&Save_t, NULL); } void ShowUsage(const char *title) { 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); #if defined(HAVE_GETRUSAGE) 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 /* HAVE_GETRUSAGE */ /* 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); } /* * on_proc_exit handler to log end of session */ static void log_disconnections(int code, Datum arg) { Port *port = MyProcPort; long secs; int usecs; int msecs; int hours, minutes, seconds; TimestampDifference(MyStartTimestamp, GetCurrentTimestamp(), &secs, &usecs); msecs = usecs / 1000; hours = secs / SECS_PER_HOUR; secs %= SECS_PER_HOUR; minutes = secs / SECS_PER_MINUTE; seconds = secs % SECS_PER_MINUTE; ereport(LOG, (errmsg("disconnection: session time: %d:%02d:%02d.%03d " "user=%s database=%s host=%s%s%s", hours, minutes, seconds, msecs, port->user_name, port->database_name, port->remote_host, port->remote_port[0] ? " port=" : "", port->remote_port))); } /* * Start statement timeout timer, if enabled. * * If there's already a timeout running, don't restart the timer. That * enables compromises between accuracy of timeouts and cost of starting a * timeout. */ static void enable_statement_timeout(void) { /* must be within an xact */ Assert(xact_started); if (StatementTimeout > 0) { if (!get_timeout_active(STATEMENT_TIMEOUT)) enable_timeout_after(STATEMENT_TIMEOUT, StatementTimeout); } else { if (get_timeout_active(STATEMENT_TIMEOUT)) disable_timeout(STATEMENT_TIMEOUT, false); } } /* * Disable statement timeout, if active. */ static void disable_statement_timeout(void) { if (get_timeout_active(STATEMENT_TIMEOUT)) disable_timeout(STATEMENT_TIMEOUT, false); }