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2065 lines
51 KiB
C
2065 lines
51 KiB
C
/*-------------------------------------------------------------------------
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*
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* postgres.c
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* POSTGRES C Backend Interface
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*
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* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.331 2003/05/03 05:13:20 momjian Exp $
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*
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* NOTES
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* this is the "main" module of the postgres backend and
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* hence the main module of the "traffic cop".
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include <unistd.h>
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#include <signal.h>
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#include <time.h>
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#include <sys/time.h>
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#include <fcntl.h>
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#include <sys/socket.h>
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#include <errno.h>
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#if HAVE_SYS_SELECT_H
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#include <sys/select.h>
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#endif
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#ifdef HAVE_GETOPT_H
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#include <getopt.h>
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#endif
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#include "access/xlog.h"
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#include "commands/async.h"
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#include "commands/trigger.h"
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#include "libpq/libpq.h"
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#include "libpq/pqformat.h"
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#include "libpq/pqsignal.h"
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#include "miscadmin.h"
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#include "nodes/print.h"
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#include "optimizer/cost.h"
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#include "optimizer/planner.h"
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#include "parser/analyze.h"
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#include "parser/parser.h"
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#include "rewrite/rewriteHandler.h"
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#include "storage/freespace.h"
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#include "storage/ipc.h"
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#include "storage/proc.h"
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#include "tcop/fastpath.h"
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#include "tcop/pquery.h"
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#include "tcop/tcopprot.h"
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#include "tcop/utility.h"
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#include "utils/guc.h"
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#include "utils/memutils.h"
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#include "utils/ps_status.h"
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#include "mb/pg_wchar.h"
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#include "pgstat.h"
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extern int optind;
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extern char *optarg;
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/* ----------------
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* global variables
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* ----------------
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*/
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const char *debug_query_string; /* for pgmonitor and
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* log_min_error_statement */
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/* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
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CommandDest whereToSendOutput = Debug;
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/* note: these declarations had better match tcopprot.h */
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sigjmp_buf Warn_restart;
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bool Warn_restart_ready = false;
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bool InError = false;
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extern bool autocommit;
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static bool EchoQuery = false; /* default don't echo */
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/*
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* Flag to mark SIGHUP. Whenever the main loop comes around it
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* will reread the configuration file. (Better than doing the
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* reading in the signal handler, ey?)
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*/
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static volatile bool got_SIGHUP = false;
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/* ----------------
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* people who want to use EOF should #define DONTUSENEWLINE in
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* tcop/tcopdebug.h
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* ----------------
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*/
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#ifndef TCOP_DONTUSENEWLINE
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int UseNewLine = 1; /* Use newlines query delimiters (the
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* default) */
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#else
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int UseNewLine = 0; /* Use EOF as query delimiters */
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#endif /* TCOP_DONTUSENEWLINE */
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/*
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** Flags for expensive function optimization -- JMH 3/9/92
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*/
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int XfuncMode = 0;
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/* ----------------------------------------------------------------
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* decls for routines only used in this file
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* ----------------------------------------------------------------
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*/
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static int InteractiveBackend(StringInfo inBuf);
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static int SocketBackend(StringInfo inBuf);
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static int ReadCommand(StringInfo inBuf);
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static void start_xact_command(void);
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static void finish_xact_command(bool forceCommit);
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static void SigHupHandler(SIGNAL_ARGS);
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static void FloatExceptionHandler(SIGNAL_ARGS);
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/* ----------------------------------------------------------------
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* routines to obtain user input
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* ----------------------------------------------------------------
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*/
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/* ----------------
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* InteractiveBackend() is called for user interactive connections
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*
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* the string entered by the user is placed in its parameter inBuf,
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* and we act like a Q message was received.
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*
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* EOF is returned if end-of-file input is seen; time to shut down.
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* ----------------
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*/
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static int
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InteractiveBackend(StringInfo inBuf)
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{
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int c; /* character read from getc() */
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bool end = false; /* end-of-input flag */
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bool backslashSeen = false; /* have we seen a \ ? */
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/*
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* display a prompt and obtain input from the user
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*/
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printf("backend> ");
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fflush(stdout);
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/* Reset inBuf to empty */
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inBuf->len = 0;
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inBuf->data[0] = '\0';
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inBuf->cursor = 0;
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for (;;)
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{
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if (UseNewLine)
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{
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/*
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* if we are using \n as a delimiter, then read characters
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* until the \n.
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*/
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while ((c = getc(stdin)) != EOF)
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{
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if (c == '\n')
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{
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if (backslashSeen)
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{
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/* discard backslash from inBuf */
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inBuf->data[--inBuf->len] = '\0';
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backslashSeen = false;
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continue;
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}
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else
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{
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/* keep the newline character */
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appendStringInfoChar(inBuf, '\n');
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break;
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}
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}
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else if (c == '\\')
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backslashSeen = true;
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else
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backslashSeen = false;
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appendStringInfoChar(inBuf, (char) c);
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}
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if (c == EOF)
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end = true;
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}
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else
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{
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/*
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* otherwise read characters until EOF.
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*/
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while ((c = getc(stdin)) != EOF)
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appendStringInfoChar(inBuf, (char) c);
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if (inBuf->len == 0)
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end = true;
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}
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if (end)
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return EOF;
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/*
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* otherwise we have a user query so process it.
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*/
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break;
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}
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/* Add '\0' to make it look the same as message case. */
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appendStringInfoChar(inBuf, (char) '\0');
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/*
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* if the query echo flag was given, print the query..
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*/
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if (EchoQuery)
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printf("statement: %s\n", inBuf->data);
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fflush(stdout);
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return 'Q';
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}
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/* ----------------
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* SocketBackend() Is called for frontend-backend connections
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*
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* Returns the message type code, and loads message body data into inBuf.
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*
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* EOF is returned if the connection is lost.
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* ----------------
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*/
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static int
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SocketBackend(StringInfo inBuf)
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{
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int qtype;
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/*
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* Get message type code from the frontend.
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*/
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qtype = pq_getbyte();
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if (qtype == EOF) /* frontend disconnected */
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{
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elog(COMMERROR, "unexpected EOF on client connection");
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return qtype;
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}
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/*
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* Validate message type code before trying to read body; if we have
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* lost sync, better to say "command unknown" than to run out of memory
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* because we used garbage as a length word.
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*/
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switch (qtype)
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{
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case 'Q': /* simple query */
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if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3)
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{
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/* old style without length word; convert */
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if (pq_getstring(inBuf))
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{
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elog(COMMERROR, "unexpected EOF on client connection");
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return EOF;
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}
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}
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break;
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case 'F': /* fastpath function call */
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break;
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case 'X': /* terminate */
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break;
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case 'd': /* copy data */
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case 'c': /* copy done */
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case 'f': /* copy fail */
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/* Accept but ignore these messages, per protocol spec */
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break;
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default:
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/*
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* Otherwise we got garbage from the frontend. We treat this
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* as fatal because we have probably lost message boundary sync,
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* and there's no good way to recover.
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*/
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elog(FATAL, "Socket command type %c unknown", qtype);
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break;
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}
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/*
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* In protocol version 3, all frontend messages have a length word
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* next after the type code; we can read the message contents
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* independently of the type.
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*/
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if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 3)
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{
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if (pq_getmessage(inBuf, 0))
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return EOF; /* suitable message already logged */
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}
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return qtype;
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}
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/* ----------------
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* ReadCommand reads a command from either the frontend or
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* standard input, places it in inBuf, and returns the
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* message type code (first byte of the message).
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* EOF is returned if end of file.
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* ----------------
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*/
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static int
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ReadCommand(StringInfo inBuf)
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{
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int result;
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if (IsUnderPostmaster)
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result = SocketBackend(inBuf);
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else
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result = InteractiveBackend(inBuf);
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return result;
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}
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/*
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* Parse a query string and pass it through the rewriter.
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*
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* A list of Query nodes is returned, since the string might contain
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* multiple queries and/or the rewriter might expand one query to several.
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*
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* NOTE: this routine is no longer used for processing interactive queries,
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* but it is still needed for parsing of SQL function bodies.
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*/
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List *
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pg_parse_and_rewrite(const char *query_string, /* string to execute */
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Oid *paramTypes, /* parameter types */
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int numParams) /* number of parameters */
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{
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List *raw_parsetree_list;
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List *querytree_list;
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List *list_item;
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/*
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* (1) parse the request string into a list of raw parse trees.
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*/
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raw_parsetree_list = pg_parse_query(query_string);
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/*
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* (2) Do parse analysis and rule rewrite.
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*/
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querytree_list = NIL;
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foreach(list_item, raw_parsetree_list)
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{
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Node *parsetree = (Node *) lfirst(list_item);
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querytree_list = nconc(querytree_list,
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pg_analyze_and_rewrite(parsetree,
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paramTypes,
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numParams));
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}
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return querytree_list;
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}
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/*
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* Do raw parsing (only).
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*
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* A list of parsetrees is returned, since there might be multiple
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* commands in the given string.
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*
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* NOTE: for interactive queries, it is important to keep this routine
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* separate from the analysis & rewrite stages. Analysis and rewriting
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* cannot be done in an aborted transaction, since they require access to
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* database tables. So, we rely on the raw parser to determine whether
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* we've seen a COMMIT or ABORT command; when we are in abort state, other
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* commands are not processed any further than the raw parse stage.
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*/
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List *
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pg_parse_query(const char *query_string)
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{
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List *raw_parsetree_list;
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if (log_statement)
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elog(LOG, "query: %s", query_string);
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if (log_parser_stats)
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ResetUsage();
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raw_parsetree_list = raw_parser(query_string);
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if (log_parser_stats)
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ShowUsage("PARSER STATISTICS");
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return raw_parsetree_list;
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}
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/*
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* Given a raw parsetree (gram.y output), and optionally information about
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* types of parameter symbols ($n), perform parse analysis and rule rewriting.
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*
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* A list of Query nodes is returned, since either the analyzer or the
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* rewriter might expand one query to several.
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*
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* NOTE: for reasons mentioned above, this must be separate from raw parsing.
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*/
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List *
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pg_analyze_and_rewrite(Node *parsetree, Oid *paramTypes, int numParams)
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{
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List *querytree_list;
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List *list_item;
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Query *querytree;
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List *new_list;
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/*
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* (1) Perform parse analysis.
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*/
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if (log_parser_stats)
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ResetUsage();
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querytree_list = parse_analyze(parsetree, paramTypes, numParams);
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if (log_parser_stats)
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{
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ShowUsage("PARSE ANALYSIS STATISTICS");
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ResetUsage();
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}
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/*
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* (2) Rewrite the queries, as necessary
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*
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* rewritten queries are collected in new_list. Note there may be more
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* or fewer than in the original list.
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*/
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new_list = NIL;
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foreach(list_item, querytree_list)
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{
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querytree = (Query *) lfirst(list_item);
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if (Debug_print_parse)
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elog_node_display(LOG, "parse tree", querytree,
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Debug_pretty_print);
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if (querytree->commandType == CMD_UTILITY)
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{
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/* don't rewrite utilities, just dump 'em into new_list */
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new_list = lappend(new_list, querytree);
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}
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else
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{
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/* rewrite regular queries */
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List *rewritten = QueryRewrite(querytree);
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new_list = nconc(new_list, rewritten);
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}
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}
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querytree_list = new_list;
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if (log_parser_stats)
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ShowUsage("REWRITER STATISTICS");
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#ifdef COPY_PARSE_PLAN_TREES
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/*
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* Optional debugging check: pass querytree output through
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* copyObject()
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*/
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new_list = (List *) copyObject(querytree_list);
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/* This checks both copyObject() and the equal() routines... */
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if (!equal(new_list, querytree_list))
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elog(WARNING, "pg_analyze_and_rewrite: copyObject failed on parse tree");
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else
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querytree_list = new_list;
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#endif
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if (Debug_print_rewritten)
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elog_node_display(LOG, "rewritten parse tree", querytree_list,
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Debug_pretty_print);
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return querytree_list;
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}
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/* Generate a plan for a single already-rewritten query. */
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Plan *
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pg_plan_query(Query *querytree)
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{
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Plan *plan;
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/* Utility commands have no plans. */
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if (querytree->commandType == CMD_UTILITY)
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return NULL;
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if (log_planner_stats)
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ResetUsage();
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/* call the optimizer */
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plan = planner(querytree, false, 0);
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if (log_planner_stats)
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ShowUsage("PLANNER STATISTICS");
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#ifdef COPY_PARSE_PLAN_TREES
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/* Optional debugging check: pass plan output through copyObject() */
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{
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Plan *new_plan = (Plan *) copyObject(plan);
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|
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/*
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* equal() currently does not have routines to compare Plan nodes,
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* so don't try to test equality here. Perhaps fix someday?
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*/
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#ifdef NOT_USED
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/* This checks both copyObject() and the equal() routines... */
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if (!equal(new_plan, plan))
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elog(WARNING, "pg_plan_query: copyObject failed on plan tree");
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else
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#endif
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plan = new_plan;
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}
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#endif
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/*
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* Print plan if debugging.
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*/
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if (Debug_print_plan)
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elog_node_display(LOG, "plan", plan, Debug_pretty_print);
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return plan;
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}
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|
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/*
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* Generate plans for a list of already-rewritten queries.
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*
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* If needSnapshot is TRUE, we haven't yet set a snapshot for the current
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* query. A snapshot must be set before invoking the planner, since it
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* might try to evaluate user-defined functions. But we must not set a
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* snapshot if the list contains only utility statements, because some
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* utility statements depend on not having frozen the snapshot yet.
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* (We assume that such statements cannot appear together with plannable
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* statements in the rewriter's output.)
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*/
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List *
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pg_plan_queries(List *querytrees, bool needSnapshot)
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{
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List *plan_list = NIL;
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List *query_list;
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foreach(query_list, querytrees)
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{
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Query *query = (Query *) lfirst(query_list);
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Plan *plan;
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|
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if (query->commandType == CMD_UTILITY)
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{
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/* Utility commands have no plans. */
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plan = NULL;
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}
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else
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{
|
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if (needSnapshot)
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{
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SetQuerySnapshot();
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needSnapshot = false;
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}
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plan = pg_plan_query(query);
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}
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plan_list = lappend(plan_list, plan);
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}
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return plan_list;
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}
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|
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|
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/*
|
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* exec_simple_query()
|
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*
|
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* Execute a "simple Query" protocol message.
|
|
*/
|
|
static void
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|
exec_simple_query(const char *query_string, /* string to execute */
|
|
CommandDest dest) /* where results should go */
|
|
{
|
|
bool xact_started;
|
|
MemoryContext oldcontext;
|
|
List *parsetree_list,
|
|
*parsetree_item;
|
|
struct timeval start_t,
|
|
stop_t;
|
|
bool save_log_duration = log_duration;
|
|
bool save_log_statement_stats = log_statement_stats;
|
|
|
|
/*
|
|
* Report query to various monitoring facilities.
|
|
*/
|
|
debug_query_string = query_string;
|
|
|
|
pgstat_report_activity(query_string);
|
|
|
|
/*
|
|
* We use save_log_duration so "SET log_duration = true" doesn't
|
|
* report incorrect time because gettimeofday() wasn't called.
|
|
* Similarly, log_statement_stats has to be captured once.
|
|
*/
|
|
if (save_log_duration)
|
|
gettimeofday(&start_t, NULL);
|
|
|
|
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();
|
|
xact_started = true;
|
|
|
|
/*
|
|
* 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);
|
|
|
|
/*
|
|
* Switch back to transaction context to enter the loop.
|
|
*/
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/*
|
|
* Run through the raw parsetree(s) and process each one.
|
|
*/
|
|
foreach(parsetree_item, parsetree_list)
|
|
{
|
|
Node *parsetree = (Node *) lfirst(parsetree_item);
|
|
const char *commandTag;
|
|
char completionTag[COMPLETION_TAG_BUFSIZE];
|
|
List *querytree_list,
|
|
*plantree_list;
|
|
Portal portal;
|
|
|
|
/*
|
|
* 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);
|
|
|
|
set_ps_display(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())
|
|
{
|
|
bool allowit = false;
|
|
|
|
if (IsA(parsetree, TransactionStmt))
|
|
{
|
|
TransactionStmt *stmt = (TransactionStmt *) parsetree;
|
|
|
|
if (stmt->kind == TRANS_STMT_COMMIT ||
|
|
stmt->kind == TRANS_STMT_ROLLBACK)
|
|
allowit = true;
|
|
}
|
|
|
|
if (!allowit)
|
|
elog(ERROR, "current transaction is aborted, "
|
|
"queries ignored until end of transaction block");
|
|
}
|
|
|
|
/* Make sure we are in a transaction command */
|
|
if (!xact_started)
|
|
{
|
|
start_xact_command();
|
|
xact_started = true;
|
|
}
|
|
|
|
/* If we got a cancel signal in parsing or prior command, quit */
|
|
CHECK_FOR_INTERRUPTS();
|
|
|
|
/*
|
|
* OK to analyze, rewrite, and plan this query.
|
|
*
|
|
* Switch to appropriate context for constructing querytrees (again,
|
|
* these must outlive the execution context).
|
|
*/
|
|
oldcontext = MemoryContextSwitchTo(MessageContext);
|
|
|
|
querytree_list = pg_analyze_and_rewrite(parsetree, NULL, 0);
|
|
|
|
plantree_list = pg_plan_queries(querytree_list, true);
|
|
|
|
/* If we got a cancel signal in analysis or planning, quit */
|
|
CHECK_FOR_INTERRUPTS();
|
|
|
|
/*
|
|
* Switch back to transaction context for execution.
|
|
*/
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/*
|
|
* Create unnamed portal to run the query or queries in.
|
|
* If there already is one, silently drop it.
|
|
*/
|
|
portal = CreatePortal("", true, true);
|
|
|
|
PortalDefineQuery(portal,
|
|
query_string,
|
|
commandTag,
|
|
querytree_list,
|
|
plantree_list,
|
|
MessageContext);
|
|
|
|
/*
|
|
* Run the portal to completion, and then drop it.
|
|
*/
|
|
PortalStart(portal, NULL);
|
|
|
|
(void) PortalRun(portal, FETCH_ALL, dest, dest, completionTag);
|
|
|
|
PortalDrop(portal, false);
|
|
|
|
/*
|
|
* If this was a transaction control statement or a variable
|
|
* set/show/reset statement, commit it and arrange to start a
|
|
* new xact command for the next command (if any).
|
|
*/
|
|
if (IsA(parsetree, TransactionStmt) ||
|
|
IsA(parsetree, VariableSetStmt) ||
|
|
IsA(parsetree, VariableShowStmt) ||
|
|
IsA(parsetree, VariableResetStmt))
|
|
{
|
|
finish_xact_command(true);
|
|
xact_started = false;
|
|
}
|
|
/*
|
|
* 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. But for compatibility with
|
|
* historical Postgres behavior, we do not force a transaction
|
|
* boundary between queries appearing in a single query string.
|
|
*/
|
|
else if (lnext(parsetree_item) == NIL || !autocommit)
|
|
{
|
|
finish_xact_command(false);
|
|
xact_started = false;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* We need a CommandCounterIncrement after every query,
|
|
* except those that start or end a transaction block.
|
|
*/
|
|
CommandCounterIncrement();
|
|
}
|
|
|
|
/*
|
|
* 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(completionTag, dest);
|
|
} /* end loop over parsetrees */
|
|
|
|
/*
|
|
* If there were no parsetrees, return EmptyQueryResponse message.
|
|
*/
|
|
if (!parsetree_list)
|
|
NullCommand(dest);
|
|
|
|
/*
|
|
* Close down transaction statement, if one is open.
|
|
*/
|
|
if (xact_started)
|
|
finish_xact_command(false);
|
|
|
|
/*
|
|
* Finish up monitoring.
|
|
*/
|
|
if (save_log_duration)
|
|
{
|
|
gettimeofday(&stop_t, NULL);
|
|
if (stop_t.tv_usec < start_t.tv_usec)
|
|
{
|
|
stop_t.tv_sec--;
|
|
stop_t.tv_usec += 1000000;
|
|
}
|
|
elog(LOG, "duration: %ld.%06ld sec",
|
|
(long) (stop_t.tv_sec - start_t.tv_sec),
|
|
(long) (stop_t.tv_usec - start_t.tv_usec));
|
|
}
|
|
|
|
if (save_log_statement_stats)
|
|
ShowUsage("QUERY STATISTICS");
|
|
|
|
debug_query_string = NULL;
|
|
}
|
|
|
|
/*
|
|
* Convenience routines for starting/committing a single command.
|
|
*/
|
|
static void
|
|
start_xact_command(void)
|
|
{
|
|
elog(DEBUG1, "StartTransactionCommand");
|
|
StartTransactionCommand(false);
|
|
|
|
/* Set statement timeout running, if any */
|
|
if (StatementTimeout > 0)
|
|
enable_sig_alarm(StatementTimeout, true);
|
|
}
|
|
|
|
static void
|
|
finish_xact_command(bool forceCommit)
|
|
{
|
|
/* Invoke IMMEDIATE constraint triggers */
|
|
DeferredTriggerEndQuery();
|
|
|
|
/* Cancel any active statement timeout before committing */
|
|
disable_sig_alarm(true);
|
|
|
|
/* Now commit the command */
|
|
elog(DEBUG1, "CommitTransactionCommand");
|
|
|
|
CommitTransactionCommand(forceCommit);
|
|
|
|
#ifdef SHOW_MEMORY_STATS
|
|
/* Print mem stats at each commit for leak tracking */
|
|
if (ShowStats)
|
|
MemoryContextStats(TopMemoryContext);
|
|
#endif
|
|
}
|
|
|
|
|
|
/* --------------------------------
|
|
* signal handler routines used in PostgresMain()
|
|
* --------------------------------
|
|
*/
|
|
|
|
/*
|
|
* quickdie() occurs when signalled SIGQUIT by the postmaster.
|
|
*
|
|
* Some backend has bought the farm,
|
|
* so we need to stop what we're doing and exit.
|
|
*/
|
|
void
|
|
quickdie(SIGNAL_ARGS)
|
|
{
|
|
PG_SETMASK(&BlockSig);
|
|
elog(WARNING, "Message from PostgreSQL backend:"
|
|
"\n\tThe Postmaster has informed me that some other backend"
|
|
"\n\tdied abnormally and possibly corrupted shared memory."
|
|
"\n\tI have rolled back the current transaction and am"
|
|
"\n\tgoing to terminate your database system connection and exit."
|
|
"\n\tPlease reconnect to the database system and repeat your query.");
|
|
|
|
/*
|
|
* DO NOT proc_exit() -- 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.
|
|
*
|
|
* Note we do exit(1) not exit(0). This is to force the postmaster into
|
|
* a system reset cycle if some idiot DBA sends a manual SIGQUIT to a
|
|
* random backend. This is necessary precisely because we don't clean
|
|
* up our shared memory state.
|
|
*/
|
|
|
|
exit(1);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
|
|
/*
|
|
* If it's safe to interrupt, and we're waiting for input or a
|
|
* lock, service the interrupt immediately
|
|
*/
|
|
if (ImmediateInterruptOK && InterruptHoldoffCount == 0 &&
|
|
CritSectionCount == 0)
|
|
{
|
|
/* bump holdoff count to make ProcessInterrupts() a no-op */
|
|
/* until we are done getting ready for it */
|
|
InterruptHoldoffCount++;
|
|
DisableNotifyInterrupt();
|
|
/* Make sure CheckDeadLock won't run while shutting down... */
|
|
LockWaitCancel();
|
|
InterruptHoldoffCount--;
|
|
ProcessInterrupts();
|
|
}
|
|
}
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
/*
|
|
* Timeout or shutdown signal from postmaster during client authentication.
|
|
* Simply exit(0).
|
|
*
|
|
* XXX: possible future improvement: try to send a message indicating
|
|
* why we are disconnecting. Problem is to be sure we don't block while
|
|
* doing so, nor mess up the authentication message exchange.
|
|
*/
|
|
void
|
|
authdie(SIGNAL_ARGS)
|
|
{
|
|
exit(0);
|
|
}
|
|
|
|
/*
|
|
* Query-cancel signal from postmaster: abort current transaction
|
|
* at soonest convenient time
|
|
*/
|
|
static void
|
|
StatementCancelHandler(SIGNAL_ARGS)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
/*
|
|
* Don't joggle the elbow of proc_exit, nor an already-in-progress
|
|
* abort
|
|
*/
|
|
if (!proc_exit_inprogress && !InError)
|
|
{
|
|
InterruptPending = true;
|
|
QueryCancelPending = true;
|
|
|
|
/*
|
|
* If it's safe to interrupt, and we're waiting for a lock,
|
|
* service the interrupt immediately. No point in interrupting if
|
|
* we're waiting for input, however.
|
|
*/
|
|
if (ImmediateInterruptOK && InterruptHoldoffCount == 0 &&
|
|
CritSectionCount == 0)
|
|
{
|
|
/* bump holdoff count to make ProcessInterrupts() a no-op */
|
|
/* until we are done getting ready for it */
|
|
InterruptHoldoffCount++;
|
|
if (LockWaitCancel())
|
|
{
|
|
DisableNotifyInterrupt();
|
|
InterruptHoldoffCount--;
|
|
ProcessInterrupts();
|
|
}
|
|
else
|
|
InterruptHoldoffCount--;
|
|
}
|
|
}
|
|
|
|
errno = save_errno;
|
|
}
|
|
|
|
/* signal handler for floating point exception */
|
|
static void
|
|
FloatExceptionHandler(SIGNAL_ARGS)
|
|
{
|
|
elog(ERROR, "floating point exception!"
|
|
" The last floating point operation either exceeded legal ranges"
|
|
" or was a divide by zero");
|
|
}
|
|
|
|
/* SIGHUP: set flag to re-read config file at next convenient time */
|
|
static void
|
|
SigHupHandler(SIGNAL_ARGS)
|
|
{
|
|
got_SIGHUP = true;
|
|
}
|
|
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
void
|
|
ProcessInterrupts(void)
|
|
{
|
|
/* OK to accept interrupt now? */
|
|
if (InterruptHoldoffCount != 0 || CritSectionCount != 0)
|
|
return;
|
|
InterruptPending = false;
|
|
if (ProcDiePending)
|
|
{
|
|
ProcDiePending = false;
|
|
QueryCancelPending = false; /* ProcDie trumps QueryCancel */
|
|
ImmediateInterruptOK = false; /* not idle anymore */
|
|
DisableNotifyInterrupt();
|
|
elog(FATAL, "This connection has been terminated by the administrator.");
|
|
}
|
|
if (QueryCancelPending)
|
|
{
|
|
QueryCancelPending = false;
|
|
ImmediateInterruptOK = false; /* not idle anymore */
|
|
DisableNotifyInterrupt();
|
|
elog(ERROR, "Query was canceled.");
|
|
}
|
|
/* If we get here, do nothing (probably, QueryCancelPending was reset) */
|
|
}
|
|
|
|
|
|
static void
|
|
usage(char *progname)
|
|
{
|
|
printf("%s is the PostgreSQL stand-alone backend. It is not\nintended to be used by normal users.\n\n", progname);
|
|
|
|
printf("Usage:\n %s [OPTION]... [DBNAME]\n\n", progname);
|
|
printf("Options:\n");
|
|
#ifdef USE_ASSERT_CHECKING
|
|
printf(" -A 1|0 enable/disable run-time assert checking\n");
|
|
#endif
|
|
printf(" -B NBUFFERS number of shared buffers (default %d)\n", DEF_NBUFFERS);
|
|
printf(" -c NAME=VALUE set run-time parameter\n");
|
|
printf(" -d 0-5 debugging level (0 is off)\n");
|
|
printf(" -D DATADIR database directory\n");
|
|
printf(" -e use European date format\n");
|
|
printf(" -E echo query before execution\n");
|
|
printf(" -F turn fsync off\n");
|
|
printf(" -N do not use newline as interactive query delimiter\n");
|
|
printf(" -o FILENAME send stdout and stderr to given file\n");
|
|
printf(" -P disable system indexes\n");
|
|
printf(" -s show statistics after each query\n");
|
|
printf(" -S SORT-MEM set amount of memory for sorts (in kbytes)\n");
|
|
printf(" --help show this help, then exit\n");
|
|
printf(" --version output version information, then exit\n");
|
|
printf("\nDeveloper options:\n");
|
|
printf(" -f s|i|n|m|h forbid use of some plan types\n");
|
|
printf(" -i do not execute queries\n");
|
|
printf(" -O allow system table structure changes\n");
|
|
printf(" -t pa|pl|ex show timings after each query\n");
|
|
printf(" -W NUM wait NUM seconds to allow attach from a debugger\n");
|
|
printf("\nReport bugs to <pgsql-bugs@postgresql.org>.\n");
|
|
}
|
|
|
|
|
|
|
|
/* ----------------------------------------------------------------
|
|
* 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.)
|
|
* username is the (possibly authenticated) PostgreSQL user name to be used
|
|
* for the session.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
int
|
|
PostgresMain(int argc, char *argv[], const char *username)
|
|
{
|
|
int flag;
|
|
const char *DBName = NULL;
|
|
char *potential_DataDir = NULL;
|
|
bool secure;
|
|
int errs = 0;
|
|
int debug_flag = 0;
|
|
GucContext ctx;
|
|
GucSource gucsource;
|
|
char *tmp;
|
|
int firstchar;
|
|
StringInfo input_message;
|
|
bool send_rfq;
|
|
|
|
/*
|
|
* Catch standard options before doing much else. This even works on
|
|
* systems without getopt_long.
|
|
*/
|
|
if (!IsUnderPostmaster && argc > 1)
|
|
{
|
|
if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
|
|
{
|
|
usage(argv[0]);
|
|
exit(0);
|
|
}
|
|
if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
|
|
{
|
|
puts("postgres (PostgreSQL) " PG_VERSION);
|
|
exit(0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* initialize globals (already done if under postmaster, but not if
|
|
* standalone; cheap enough to do over)
|
|
*/
|
|
|
|
MyProcPid = getpid();
|
|
|
|
/*
|
|
* Fire up essential subsystems: error and memory management
|
|
*
|
|
* If we are running under the postmaster, this is done already.
|
|
*/
|
|
if (!IsUnderPostmaster)
|
|
MemoryContextInit();
|
|
|
|
set_ps_display("startup");
|
|
|
|
SetProcessingMode(InitProcessing);
|
|
|
|
/*
|
|
* Set default values for command-line options.
|
|
*/
|
|
Noversion = false;
|
|
EchoQuery = false;
|
|
|
|
if (!IsUnderPostmaster || ExecBackend)
|
|
{
|
|
InitializeGUCOptions();
|
|
#ifdef EXEC_BACKEND
|
|
read_nondefault_variables();
|
|
#endif
|
|
potential_DataDir = getenv("PGDATA");
|
|
}
|
|
|
|
/* ----------------
|
|
* parse command line arguments
|
|
*
|
|
* There are now two styles of command line layout for the backend:
|
|
*
|
|
* For interactive use (not started from postmaster) the format is
|
|
* postgres [switches] [databasename]
|
|
* If the databasename is omitted it is taken to be the user name.
|
|
*
|
|
* When started from the postmaster, the format is
|
|
* postgres [secure switches] -p databasename [insecure switches]
|
|
* Switches appearing after -p came from the client (via "options"
|
|
* field of connection request). For security reasons we restrict
|
|
* what these switches can do.
|
|
* ----------------
|
|
*/
|
|
|
|
/* all options are allowed until '-p' */
|
|
secure = true;
|
|
ctx = PGC_POSTMASTER;
|
|
gucsource = PGC_S_ARGV; /* initial switches came from command line */
|
|
|
|
while ((flag = getopt(argc, argv, "A:B:c:CD:d:Eef:FiNOPo:p:S:st:v:W:x:-:")) != -1)
|
|
switch (flag)
|
|
{
|
|
case 'A':
|
|
#ifdef USE_ASSERT_CHECKING
|
|
SetConfigOption("debug_assertions", optarg, ctx, gucsource);
|
|
#else
|
|
elog(WARNING, "Assert checking is not compiled in");
|
|
#endif
|
|
break;
|
|
|
|
case 'B':
|
|
|
|
/*
|
|
* specify the size of buffer pool
|
|
*/
|
|
SetConfigOption("shared_buffers", optarg, ctx, gucsource);
|
|
break;
|
|
|
|
case 'C':
|
|
|
|
/*
|
|
* don't print version string
|
|
*/
|
|
Noversion = true;
|
|
break;
|
|
|
|
case 'D': /* PGDATA directory */
|
|
if (secure)
|
|
potential_DataDir = optarg;
|
|
break;
|
|
|
|
case 'd': /* debug level */
|
|
{
|
|
debug_flag = atoi(optarg);
|
|
/* Set server debugging level. */
|
|
if (atoi(optarg) != 0)
|
|
{
|
|
char *debugstr = palloc(strlen("debug") + strlen(optarg) + 1);
|
|
|
|
sprintf(debugstr, "debug%s", optarg);
|
|
SetConfigOption("log_min_messages", debugstr, ctx, gucsource);
|
|
pfree(debugstr);
|
|
|
|
}
|
|
else
|
|
/*
|
|
* -d0 allows user to prevent postmaster debug
|
|
* from propagating to backend. It would be nice
|
|
* to set it to the postgresql.conf value here.
|
|
*/
|
|
SetConfigOption("log_min_messages", "notice",
|
|
ctx, gucsource);
|
|
}
|
|
break;
|
|
|
|
case 'E':
|
|
|
|
/*
|
|
* E - echo the query the user entered
|
|
*/
|
|
EchoQuery = true;
|
|
break;
|
|
|
|
case 'e':
|
|
|
|
/*
|
|
* Use european date formats.
|
|
*/
|
|
SetConfigOption("datestyle", "euro", ctx, gucsource);
|
|
break;
|
|
|
|
case 'F':
|
|
|
|
/*
|
|
* turn off fsync
|
|
*/
|
|
SetConfigOption("fsync", "false", ctx, gucsource);
|
|
break;
|
|
|
|
case 'f':
|
|
|
|
/*
|
|
* f - forbid generation of certain plans
|
|
*/
|
|
tmp = NULL;
|
|
switch (optarg[0])
|
|
{
|
|
case 's': /* seqscan */
|
|
tmp = "enable_seqscan";
|
|
break;
|
|
case 'i': /* indexscan */
|
|
tmp = "enable_indexscan";
|
|
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;
|
|
default:
|
|
errs++;
|
|
}
|
|
if (tmp)
|
|
SetConfigOption(tmp, "false", ctx, gucsource);
|
|
break;
|
|
|
|
case 'N':
|
|
|
|
/*
|
|
* N - Don't use newline as a query delimiter
|
|
*/
|
|
UseNewLine = 0;
|
|
break;
|
|
|
|
case 'O':
|
|
|
|
/*
|
|
* allow system table structure modifications
|
|
*/
|
|
if (secure) /* XXX safe to allow from client??? */
|
|
allowSystemTableMods = true;
|
|
break;
|
|
|
|
case 'P':
|
|
|
|
/*
|
|
* ignore system indexes
|
|
*/
|
|
if (secure) /* XXX safe to allow from client??? */
|
|
IgnoreSystemIndexes(true);
|
|
break;
|
|
|
|
case 'o':
|
|
|
|
/*
|
|
* o - send output (stdout and stderr) to the given file
|
|
*/
|
|
if (secure)
|
|
StrNCpy(OutputFileName, optarg, MAXPGPATH);
|
|
break;
|
|
|
|
case 'p':
|
|
|
|
/*
|
|
* p - special flag passed if backend was forked by a
|
|
* postmaster.
|
|
*/
|
|
if (secure)
|
|
{
|
|
DBName = strdup(optarg);
|
|
secure = false; /* subsequent switches are NOT
|
|
* secure */
|
|
ctx = PGC_BACKEND;
|
|
gucsource = PGC_S_CLIENT;
|
|
}
|
|
break;
|
|
|
|
case 'S':
|
|
|
|
/*
|
|
* S - amount of sort memory to use in 1k bytes
|
|
*/
|
|
SetConfigOption("sort_mem", optarg, ctx, gucsource);
|
|
break;
|
|
|
|
case 's':
|
|
|
|
/*
|
|
* s - report usage statistics (timings) after each query
|
|
*/
|
|
SetConfigOption("show_statement_stats", "true", ctx, gucsource);
|
|
break;
|
|
|
|
case 't':
|
|
/* ---------------
|
|
* tell postgres to report usage statistics (timings) for
|
|
* each query
|
|
*
|
|
* -tpa[rser] = print stats for parser time of each query
|
|
* -tpl[anner] = print stats for planner time of each query
|
|
* -te[xecutor] = print stats for executor time of each query
|
|
* caution: -s can not be used together with -t.
|
|
* ----------------
|
|
*/
|
|
tmp = NULL;
|
|
switch (optarg[0])
|
|
{
|
|
case 'p':
|
|
if (optarg[1] == 'a')
|
|
tmp = "log_parser_stats";
|
|
else if (optarg[1] == 'l')
|
|
tmp = "log_planner_stats";
|
|
else
|
|
errs++;
|
|
break;
|
|
case 'e':
|
|
tmp = "show_executor_stats";
|
|
break;
|
|
default:
|
|
errs++;
|
|
break;
|
|
}
|
|
if (tmp)
|
|
SetConfigOption(tmp, "true", ctx, gucsource);
|
|
break;
|
|
|
|
case 'v':
|
|
if (secure)
|
|
FrontendProtocol = (ProtocolVersion) atoi(optarg);
|
|
break;
|
|
|
|
case 'W':
|
|
|
|
/*
|
|
* wait N seconds to allow attach from a debugger
|
|
*/
|
|
sleep(atoi(optarg));
|
|
break;
|
|
|
|
case 'x':
|
|
#ifdef NOT_USED /* planner/xfunc.h */
|
|
|
|
/*
|
|
* control joey hellerstein's expensive function
|
|
* optimization
|
|
*/
|
|
if (XfuncMode != 0)
|
|
{
|
|
elog(WARNING, "only one -x flag is allowed");
|
|
errs++;
|
|
break;
|
|
}
|
|
if (strcmp(optarg, "off") == 0)
|
|
XfuncMode = XFUNC_OFF;
|
|
else if (strcmp(optarg, "nor") == 0)
|
|
XfuncMode = XFUNC_NOR;
|
|
else if (strcmp(optarg, "nopull") == 0)
|
|
XfuncMode = XFUNC_NOPULL;
|
|
else if (strcmp(optarg, "nopm") == 0)
|
|
XfuncMode = XFUNC_NOPM;
|
|
else if (strcmp(optarg, "pullall") == 0)
|
|
XfuncMode = XFUNC_PULLALL;
|
|
else if (strcmp(optarg, "wait") == 0)
|
|
XfuncMode = XFUNC_WAIT;
|
|
else
|
|
{
|
|
elog(WARNING, "use -x {off,nor,nopull,nopm,pullall,wait}");
|
|
errs++;
|
|
}
|
|
#endif
|
|
break;
|
|
|
|
case 'c':
|
|
case '-':
|
|
{
|
|
char *name,
|
|
*value;
|
|
|
|
ParseLongOption(optarg, &name, &value);
|
|
if (!value)
|
|
{
|
|
if (flag == '-')
|
|
elog(ERROR, "--%s requires argument", optarg);
|
|
else
|
|
elog(ERROR, "-c %s requires argument", optarg);
|
|
}
|
|
|
|
SetConfigOption(name, value, ctx, gucsource);
|
|
free(name);
|
|
if (value)
|
|
free(value);
|
|
break;
|
|
}
|
|
|
|
default:
|
|
errs++;
|
|
break;
|
|
}
|
|
|
|
|
|
/*
|
|
* -d is not the same as setting
|
|
* log_min_messages because it enables other
|
|
* output options.
|
|
*/
|
|
if (debug_flag >= 1)
|
|
SetConfigOption("log_connections", "true", ctx, gucsource);
|
|
if (debug_flag >= 2)
|
|
SetConfigOption("log_statement", "true", ctx, gucsource);
|
|
if (debug_flag >= 3)
|
|
SetConfigOption("debug_print_parse", "true", ctx, gucsource);
|
|
if (debug_flag >= 4)
|
|
SetConfigOption("debug_print_plan", "true", ctx, gucsource);
|
|
if (debug_flag >= 5)
|
|
SetConfigOption("debug_print_rewritten", "true", ctx, gucsource);
|
|
|
|
/*
|
|
* Process any additional GUC variable settings passed in startup packet.
|
|
*/
|
|
if (MyProcPort != NULL)
|
|
{
|
|
List *gucopts = MyProcPort->guc_options;
|
|
|
|
while (gucopts)
|
|
{
|
|
char *name,
|
|
*value;
|
|
|
|
name = lfirst(gucopts);
|
|
gucopts = lnext(gucopts);
|
|
value = lfirst(gucopts);
|
|
gucopts = lnext(gucopts);
|
|
SetConfigOption(name, value, PGC_BACKEND, PGC_S_CLIENT);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Post-processing for command line options.
|
|
*/
|
|
if (log_statement_stats &&
|
|
(log_parser_stats || log_planner_stats || log_executor_stats))
|
|
{
|
|
elog(WARNING, "Query statistics are disabled because parser, planner, or executor statistics are on.");
|
|
SetConfigOption("show_statement_stats", "false", ctx, gucsource);
|
|
}
|
|
|
|
if (!IsUnderPostmaster)
|
|
{
|
|
if (!potential_DataDir)
|
|
{
|
|
fprintf(stderr, "%s does not know where to find the database system "
|
|
"data. You must specify the directory that contains the "
|
|
"database system either by specifying the -D invocation "
|
|
"option or by setting the PGDATA environment variable.\n\n",
|
|
argv[0]);
|
|
proc_exit(1);
|
|
}
|
|
SetDataDir(potential_DataDir);
|
|
}
|
|
Assert(DataDir);
|
|
|
|
/*
|
|
* Set up signal handlers and masks.
|
|
*
|
|
* 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.)
|
|
*/
|
|
|
|
pqsignal(SIGHUP, SigHupHandler); /* set flag to read config file */
|
|
pqsignal(SIGINT, StatementCancelHandler); /* cancel current query */
|
|
pqsignal(SIGTERM, die); /* cancel current query and exit */
|
|
pqsignal(SIGQUIT, quickdie); /* hard crash time */
|
|
pqsignal(SIGALRM, handle_sig_alarm); /* timeout conditions */
|
|
|
|
/*
|
|
* 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, SIG_IGN); /* this signal available for use */
|
|
|
|
pqsignal(SIGUSR2, Async_NotifyHandler); /* flush also sinval cache */
|
|
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 */
|
|
|
|
pqinitmask();
|
|
|
|
/* We allow SIGQUIT (quickdie) at all times */
|
|
#ifdef HAVE_SIGPROCMASK
|
|
sigdelset(&BlockSig, SIGQUIT);
|
|
#else
|
|
BlockSig &= ~(sigmask(SIGQUIT));
|
|
#endif
|
|
|
|
PG_SETMASK(&BlockSig); /* block everything except SIGQUIT */
|
|
|
|
|
|
if (IsUnderPostmaster)
|
|
{
|
|
/* noninteractive case: nothing should be left after switches */
|
|
if (errs || argc != optind || DBName == NULL)
|
|
{
|
|
elog(WARNING, "%s: invalid command line arguments\nTry -? for help.",
|
|
argv[0]);
|
|
proc_exit(0); /* not 1, that causes system-wide
|
|
* restart... */
|
|
}
|
|
BaseInit();
|
|
#ifdef EXECBACKEND
|
|
AttachSharedMemoryAndSemaphores();
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
/* interactive case: database name can be last arg on command line */
|
|
if (errs || argc - optind > 1)
|
|
{
|
|
elog(WARNING, "%s: invalid command line arguments\nTry -? for help.",
|
|
argv[0]);
|
|
proc_exit(1);
|
|
}
|
|
else if (argc - optind == 1)
|
|
DBName = argv[optind];
|
|
else if ((DBName = username) == NULL)
|
|
{
|
|
elog(WARNING, "%s: user name undefined and no database specified",
|
|
argv[0]);
|
|
proc_exit(1);
|
|
}
|
|
|
|
/*
|
|
* On some systems our dynloader code needs the executable's
|
|
* pathname. (If under postmaster, this was done already.)
|
|
*/
|
|
if (FindExec(pg_pathname, argv[0], "postgres") < 0)
|
|
elog(FATAL, "%s: could not locate executable, bailing out...",
|
|
argv[0]);
|
|
|
|
/*
|
|
* Validate we have been given a reasonable-looking DataDir (if
|
|
* under postmaster, assume postmaster did this already).
|
|
*/
|
|
ValidatePgVersion(DataDir);
|
|
|
|
/*
|
|
* Create lockfile for data directory.
|
|
*/
|
|
if (!CreateDataDirLockFile(DataDir, false))
|
|
proc_exit(1);
|
|
|
|
XLOGPathInit();
|
|
BaseInit();
|
|
|
|
/*
|
|
* Start up xlog for standalone backend, and register to have it
|
|
* closed down at exit.
|
|
*/
|
|
StartupXLOG();
|
|
on_shmem_exit(ShutdownXLOG, 0);
|
|
|
|
/*
|
|
* Read any existing FSM cache file, and register to write one out
|
|
* at exit.
|
|
*/
|
|
LoadFreeSpaceMap();
|
|
on_shmem_exit(DumpFreeSpaceMap, 0);
|
|
}
|
|
|
|
/*
|
|
* Set up additional info.
|
|
*/
|
|
|
|
#ifdef CYR_RECODE
|
|
SetCharSet();
|
|
#endif
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
elog(DEBUG2, "InitPostgres");
|
|
InitPostgres(DBName, username);
|
|
|
|
SetProcessingMode(NormalProcessing);
|
|
|
|
/*
|
|
* Send this backend's cancellation info to the frontend.
|
|
*/
|
|
if (whereToSendOutput == Remote &&
|
|
PG_PROTOCOL_MAJOR(FrontendProtocol) >= 2)
|
|
{
|
|
StringInfoData buf;
|
|
|
|
pq_beginmessage(&buf, 'K');
|
|
pq_sendint(&buf, (int32) MyProcPid, sizeof(int32));
|
|
pq_sendint(&buf, (int32) MyCancelKey, sizeof(int32));
|
|
pq_endmessage(&buf);
|
|
/* Need not flush since ReadyForQuery will do it. */
|
|
}
|
|
|
|
if (!IsUnderPostmaster)
|
|
{
|
|
puts("\nPOSTGRES backend interactive interface ");
|
|
puts("$Revision: 1.331 $ $Date: 2003/05/03 05:13:20 $\n");
|
|
}
|
|
|
|
/*
|
|
* 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_MINSIZE,
|
|
ALLOCSET_DEFAULT_INITSIZE,
|
|
ALLOCSET_DEFAULT_MAXSIZE);
|
|
|
|
/* ----------
|
|
* Tell the statistics collector that we're alive and
|
|
* to which database we belong.
|
|
* ----------
|
|
*/
|
|
pgstat_bestart();
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
|
|
if (sigsetjmp(Warn_restart, 1) != 0)
|
|
{
|
|
/*
|
|
* NOTE: if you are tempted to add more code in this if-block,
|
|
* consider the probability that it should be in
|
|
* AbortTransaction() instead.
|
|
*
|
|
* Make sure we're not interrupted while cleaning up. Also forget
|
|
* any pending QueryCancel request, since we're aborting anyway.
|
|
* Force InterruptHoldoffCount to a known state in case we elog'd
|
|
* from inside a holdoff section.
|
|
*/
|
|
ImmediateInterruptOK = false;
|
|
QueryCancelPending = false;
|
|
InterruptHoldoffCount = 1;
|
|
CritSectionCount = 0; /* should be unnecessary, but... */
|
|
disable_sig_alarm(true);
|
|
QueryCancelPending = false; /* again in case timeout occurred */
|
|
DisableNotifyInterrupt();
|
|
debug_query_string = NULL;
|
|
|
|
/*
|
|
* Make sure we are in a valid memory context during recovery.
|
|
*
|
|
* We use ErrorContext in hopes that it will have some free space
|
|
* even if we're otherwise up against it...
|
|
*/
|
|
MemoryContextSwitchTo(ErrorContext);
|
|
|
|
/* Do the recovery */
|
|
elog(DEBUG1, "AbortCurrentTransaction");
|
|
AbortCurrentTransaction();
|
|
|
|
/*
|
|
* Now return to normal top-level context and clear ErrorContext
|
|
* for next time.
|
|
*/
|
|
MemoryContextSwitchTo(TopMemoryContext);
|
|
MemoryContextResetAndDeleteChildren(ErrorContext);
|
|
CurrentPortal = NULL;
|
|
PortalContext = NULL;
|
|
QueryContext = NULL;
|
|
|
|
/*
|
|
* Clear flag to indicate that we got out of error recovery mode
|
|
* successfully. (Flag was set in elog.c before longjmp().)
|
|
*/
|
|
InError = false;
|
|
|
|
/*
|
|
* Exit interrupt holdoff section we implicitly established above.
|
|
*/
|
|
RESUME_INTERRUPTS();
|
|
}
|
|
|
|
Warn_restart_ready = true; /* we can now handle elog(ERROR) */
|
|
|
|
PG_SETMASK(&UnBlockSig);
|
|
|
|
send_rfq = true; /* initially, or after error */
|
|
|
|
/*
|
|
* Non-error queries loop here.
|
|
*/
|
|
|
|
for (;;)
|
|
{
|
|
/*
|
|
* Release storage left over from prior query cycle, and create a
|
|
* new query input buffer in the cleared MessageContext.
|
|
*/
|
|
MemoryContextSwitchTo(MessageContext);
|
|
MemoryContextResetAndDeleteChildren(MessageContext);
|
|
|
|
input_message = makeStringInfo();
|
|
|
|
/*
|
|
* (1) tell the frontend we're ready for a new query.
|
|
*
|
|
* Note: this includes fflush()'ing the last of the prior output.
|
|
*/
|
|
if (send_rfq)
|
|
{
|
|
ReadyForQuery(whereToSendOutput);
|
|
send_rfq = false;
|
|
}
|
|
|
|
/* ----------
|
|
* Tell the statistics collector what we've collected
|
|
* so far.
|
|
* ----------
|
|
*/
|
|
pgstat_report_tabstat();
|
|
|
|
if (IsTransactionBlock())
|
|
{
|
|
set_ps_display("idle in transaction");
|
|
pgstat_report_activity("<IDLE> in transaction");
|
|
}
|
|
else
|
|
{
|
|
set_ps_display("idle");
|
|
pgstat_report_activity("<IDLE>");
|
|
}
|
|
|
|
/*
|
|
* (2) deal with pending asynchronous NOTIFY from other backends,
|
|
* and enable async.c's signal handler to execute NOTIFY directly.
|
|
* Then set up other stuff needed before blocking for input.
|
|
*/
|
|
QueryCancelPending = false; /* forget any earlier CANCEL
|
|
* signal */
|
|
|
|
EnableNotifyInterrupt();
|
|
|
|
/* Allow "die" interrupt to be processed while waiting */
|
|
ImmediateInterruptOK = true;
|
|
/* and don't forget to detect one that already arrived */
|
|
QueryCancelPending = false;
|
|
CHECK_FOR_INTERRUPTS();
|
|
|
|
/*
|
|
* (3) read a command (loop blocks here)
|
|
*/
|
|
firstchar = ReadCommand(input_message);
|
|
|
|
/*
|
|
* (4) disable async signal conditions again.
|
|
*/
|
|
ImmediateInterruptOK = false;
|
|
QueryCancelPending = false; /* forget any CANCEL signal */
|
|
|
|
DisableNotifyInterrupt();
|
|
|
|
/*
|
|
* (5) check for any other interesting events that happened while
|
|
* we slept.
|
|
*/
|
|
if (got_SIGHUP)
|
|
{
|
|
got_SIGHUP = false;
|
|
ProcessConfigFile(PGC_SIGHUP);
|
|
}
|
|
|
|
/*
|
|
* (6) process the command.
|
|
*/
|
|
switch (firstchar)
|
|
{
|
|
case 'Q': /* simple query */
|
|
{
|
|
const char *query_string = pq_getmsgstring(input_message);
|
|
|
|
exec_simple_query(query_string, whereToSendOutput);
|
|
|
|
send_rfq = true;
|
|
}
|
|
break;
|
|
|
|
case 'F': /* fastpath function call */
|
|
/* Tell the collector what we're doing */
|
|
pgstat_report_activity("<FASTPATH> function call");
|
|
|
|
/* start an xact for this function invocation */
|
|
start_xact_command();
|
|
|
|
if (HandleFunctionRequest(input_message) == EOF)
|
|
{
|
|
/* lost frontend connection during F message input */
|
|
|
|
/*
|
|
* Reset whereToSendOutput to prevent elog from
|
|
* attempting to send any more messages to client.
|
|
*/
|
|
if (whereToSendOutput == Remote)
|
|
whereToSendOutput = None;
|
|
|
|
proc_exit(0);
|
|
}
|
|
|
|
/* commit the function-invocation transaction */
|
|
finish_xact_command(false);
|
|
|
|
send_rfq = 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 'X':
|
|
case EOF:
|
|
|
|
/*
|
|
* Reset whereToSendOutput to prevent elog from attempting
|
|
* to send any more messages to client.
|
|
*/
|
|
if (whereToSendOutput == Remote)
|
|
whereToSendOutput = None;
|
|
|
|
/*
|
|
* 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:
|
|
elog(FATAL, "Socket command type %c unknown", firstchar);
|
|
}
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
/*
|
|
* Check all memory after each backend loop. This is a rather
|
|
* weird place to do it, perhaps.
|
|
*/
|
|
MemoryContextCheck(TopMemoryContext);
|
|
#endif
|
|
} /* end of input-reading loop */
|
|
|
|
/* can't get here because the above loop never exits */
|
|
Assert(false);
|
|
|
|
return 1; /* keep compiler quiet */
|
|
}
|
|
|
|
#ifndef HAVE_GETRUSAGE
|
|
#include "rusagestub.h"
|
|
#else
|
|
#include <sys/resource.h>
|
|
#endif /* HAVE_GETRUSAGE */
|
|
|
|
struct rusage Save_r;
|
|
struct timeval Save_t;
|
|
|
|
void
|
|
ResetUsage(void)
|
|
{
|
|
getrusage(RUSAGE_SELF, &Save_r);
|
|
gettimeofday(&Save_t, NULL);
|
|
ResetBufferUsage();
|
|
/* ResetTupleCount(); */
|
|
}
|
|
|
|
void
|
|
ShowUsage(const char *title)
|
|
{
|
|
StringInfoData str;
|
|
struct timeval user,
|
|
sys;
|
|
struct timeval elapse_t;
|
|
struct rusage r;
|
|
char *bufusage;
|
|
|
|
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 for memory usage -- i can't
|
|
* figure out how to interpret the relevant fields in the rusage
|
|
* struct, and they change names across o/s platforms, anyway. if you
|
|
* can figure out what the entries mean, you can somehow extract
|
|
* resident set size, shared text size, and unshared data and stack
|
|
* sizes.
|
|
*/
|
|
initStringInfo(&str);
|
|
|
|
appendStringInfo(&str, "! system usage stats:\n");
|
|
appendStringInfo(&str,
|
|
"!\t%ld.%06ld elapsed %ld.%06ld user %ld.%06ld system sec\n",
|
|
(long) (elapse_t.tv_sec - Save_t.tv_sec),
|
|
(long) (elapse_t.tv_usec - Save_t.tv_usec),
|
|
(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));
|
|
appendStringInfo(&str,
|
|
"!\t[%ld.%06ld user %ld.%06ld sys total]\n",
|
|
(long) user.tv_sec,
|
|
(long) user.tv_usec,
|
|
(long) sys.tv_sec,
|
|
(long) sys.tv_usec);
|
|
/* BeOS has rusage but only has some fields, and not these... */
|
|
#if defined(HAVE_GETRUSAGE)
|
|
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 */
|
|
|
|
bufusage = ShowBufferUsage();
|
|
appendStringInfo(&str, "! buffer usage stats:\n%s", bufusage);
|
|
pfree(bufusage);
|
|
|
|
/* remove trailing newline */
|
|
if (str.data[str.len - 1] == '\n')
|
|
str.data[--str.len] = '\0';
|
|
|
|
elog(LOG, "%s\n%s", title, str.data);
|
|
|
|
pfree(str.data);
|
|
}
|