postgres.c

关系型数据库 Postgresql 6.5.2

				/* ----------------
				 *	T - tracing options
				 * ----------------
				 */
				parse_options(optarg, secure);
				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.
				 * ----------------
				 */
				StatFp = stderr;
				switch (optarg[0])
				{
					case 'p':
						if (optarg[1] == 'a')
							ShowParserStats = 1;
						else if (optarg[1] == 'l')
							ShowPlannerStats = 1;
						else
							errs++;
						break;
					case 'e':
						ShowExecutorStats = 1;
						break;
					default:
						errs++;
						break;
				}
				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)
				{
					fprintf(stderr, "only one -x flag is allowed\n");
					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
				{
					fprintf(stderr, "use -x {off,nor,nopull,nopm,pullall,wait}\n");
					errs++;
				}
#endif
				break;

			default:
				/* ----------------
				 *	default: bad command line option
				 * ----------------
				 */
				errs++;
				break;
		}

	/* ----------------
	 *	get user name (needed now in case it is the default database name)
	 *	and check command line validity
	 * ----------------
	 */
	SetPgUserName();
	userName = GetPgUserName();

	if (IsUnderPostmaster)
	{
		/* noninteractive case: nothing should be left after switches */
		if (errs || argc != optind || DBName == NULL)
		{
			usage(argv[0]);
			proc_exit(1);
		}
	}
	else
	{
		/* interactive case: database name can be last arg on command line */
		if (errs || argc - optind > 1)
		{
			usage(argv[0]);
			proc_exit(1);
		}
		else if (argc - optind == 1)
			DBName = argv[optind];
		else if ((DBName = userName) == NULL)
		{
			fprintf(stderr, "%s: USER undefined and no database specified\n",
					argv[0]);
			proc_exit(1);
		}
	}

	if (ShowStats &&
		(ShowParserStats || ShowPlannerStats || ShowExecutorStats))
	{
		fprintf(stderr, "-s can not be used together with -t.\n");
		proc_exit(1);
	}

	if (!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);
	}

	/*
	 * Set up additional info.
	 */

#ifdef CYR_RECODE
	SetCharSet();
#endif

	if (FindExec(pg_pathname, argv[0], "postgres") < 0)
		elog(FATAL, "%s: could not locate executable, bailing out...",
			 argv[0]);

	/*
	 * Find remote host name or address.
	 */
	if (IsUnderPostmaster)
	{
		switch (MyProcPort->raddr.sa.sa_family)
		{
				struct hostent *host_ent;

			case AF_INET:
				remote_info = remote_host = malloc(48);
				remote_port = ntohs(MyProcPort->raddr.in.sin_port);
				strcpy(remote_host, inet_ntoa(MyProcPort->raddr.in.sin_addr));
				if (HostnameLookup)
				{
					host_ent = \
						gethostbyaddr((char *) &MyProcPort->raddr.in.sin_addr,
								   sizeof(MyProcPort->raddr.in.sin_addr),
									  AF_INET);
					if (host_ent)
					{
						strncpy(remote_host, host_ent->h_name, 48);
						*(remote_host + 47) = '\0';
					}
				}
				if (ShowPortNumber)
				{
					remote_info = malloc(strlen(remote_host) + 6);
					sprintf(remote_info, "%s:%d", remote_host, remote_port);
				}
				break;
			case AF_UNIX:
				remote_info = remote_host = "localhost";
				break;
			default:
				remote_info = remote_host = "unknown";
				break;
		}
	}

	/* ----------------
	 *	set process params for ps
	 * ----------------
	 */
	if (IsUnderPostmaster)
	{
		PS_INIT_STATUS(real_argc, real_argv, argv[0],
					   remote_info, userName, DBName);
		PS_SET_STATUS("startup");
	}

	/* ----------------
	 *	print flags
	 * ----------------
	 */
	if (Verbose)
	{
		if (Verbose == 1)
		{
			TPRINTF(TRACE_VERBOSE, "started: host=%s user=%s database=%s",
					remote_host, userName, DBName);
		}
		else
		{
			TPRINTF(TRACE_VERBOSE, "debug info:");
			TPRINTF(TRACE_VERBOSE, "\tUser         = %s", userName);
			TPRINTF(TRACE_VERBOSE, "\tRemoteHost   = %s", remote_host);
			TPRINTF(TRACE_VERBOSE, "\tRemotePort   = %d", remote_port);
			TPRINTF(TRACE_VERBOSE, "\tDatabaseName = %s", DBName);
			TPRINTF(TRACE_VERBOSE, "\tVerbose      = %d", Verbose);
			TPRINTF(TRACE_VERBOSE, "\tNoversion    = %c", Noversion ? 't' : 'f');
			TPRINTF(TRACE_VERBOSE, "\ttimings      = %c", ShowStats ? 't' : 'f');
			TPRINTF(TRACE_VERBOSE, "\tdates        = %s",
					EuroDates ? "European" : "Normal");
			TPRINTF(TRACE_VERBOSE, "\tbufsize      = %d", NBuffers);
			TPRINTF(TRACE_VERBOSE, "\tsortmem      = %d", SortMem);
			TPRINTF(TRACE_VERBOSE, "\tquery echo   = %c", EchoQuery ? 't' : 'f');
		}
	}

	/* ----------------
	 *	initialize I/O
	 * ----------------
	 */
	if (IsUnderPostmaster)
	{
		pq_init();				/* initialize libpq at backend startup */
		whereToSendOutput = Remote;
	}
	else
		whereToSendOutput = Debug;

	/* ----------------
	 *	general initialization
	 * ----------------
	 */
	SetProcessingMode(InitProcessing);

	if (Verbose)
		TPRINTF(TRACE_VERBOSE, "InitPostgres");

	InitPostgres(DBName);

#ifdef MULTIBYTE
	/* set default client encoding */
	if (Verbose)
		puts("\treset_client_encoding()..");
	reset_client_encoding();
	if (Verbose)
		puts("\treset_client_encoding() done.");
#endif

	on_shmem_exit(remove_all_temp_relations, NULL);

	/* ----------------
	 *	Set up handler for cancel-request signal, and
	 *	send this backend's cancellation info to the frontend.
	 *	This should not be done until we are sure startup is successful.
	 * ----------------
	 */

	pqsignal(SIGHUP, read_pg_options);	/* update pg_options from file */
	pqsignal(SIGINT, QueryCancelHandler);		/* cancel current query */
	pqsignal(SIGQUIT, handle_warn);		/* handle error */
	pqsignal(SIGTERM, die);
	pqsignal(SIGPIPE, SIG_IGN); /* 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(SIGUSR1, quickdie);
	pqsignal(SIGUSR2, Async_NotifyHandler);		/* flush also sinval cache */
	pqsignal(SIGCHLD, SIG_IGN); /* ignored, sent by LockOwners */
	pqsignal(SIGFPE, FloatExceptionHandler);

	if (whereToSendOutput == Remote &&
		PG_PROTOCOL_MAJOR(FrontendProtocol) >= 2)
	{
		StringInfoData buf;

		pq_beginmessage(&buf);
		pq_sendbyte(&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: 1.119 $ $Date: 1999/07/02 18:09:27 $\n");
	}

	/* ----------------
	 *	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.
	 *
	 *	Note:  elog(ERROR) does a siglongjmp() to transfer control here.
	 * ----------------
	 */

	if (sigsetjmp(Warn_restart, 1) != 0)
	{
		InError = true;

		time(&tim);

		if (Verbose)
			TPRINTF(TRACE_VERBOSE, "AbortCurrentTransaction");

		AbortCurrentTransaction();
	}

	InError = false;

	/*
	 * Non-error queries loop here.
	 */

	for (;;)
	{
		PS_SET_STATUS("idle");

		/* ----------------
		 *	 (1) tell the frontend we're ready for a new query.
		 *
		 *	 Note: this includes fflush()'ing the last of the prior output.
		 * ----------------
		 */
		ReadyForQuery(whereToSendOutput);

		/* ----------------
		 *	 (2) deal with pending asynchronous NOTIFY from other backends,
		 *	 and enable async.c's signal handler to execute NOTIFY directly.
		 * ----------------
		 */
		QueryCancel = false;	/* forget any earlier CANCEL signal */

		EnableNotifyInterrupt();

		/* ----------------
		 *	 (3) read a command.
		 * ----------------
		 */
		MemSet(parser_input, 0, MAX_PARSE_BUFFER);

		firstchar = ReadCommand(parser_input);

		QueryCancel = false;	/* forget any earlier CANCEL signal */

		/* ----------------
		 *	 (4) disable async.c's signal handler.
		 * ----------------
		 */
		DisableNotifyInterrupt();

		/* ----------------
		 *	 (5) process the command.
		 * ----------------
		 */
		switch (firstchar)
		{
				/* ----------------
				 *	'F' indicates a fastpath call.
				 *		XXX HandleFunctionRequest
				 * ----------------
				 */
			case 'F':
				IsEmptyQuery = false;

				/* start an xact for this function invocation */
				if (Verbose)
					TPRINTF(TRACE_VERBOSE, "StartTransactionCommand");
				StartTransactionCommand();

				HandleFunctionRequest();
				break;

				/* ----------------
				 *	'Q' indicates a user query
				 * ----------------
				 */
			case 'Q':
				if (strspn(parser_input, " \t\n") == strlen(parser_input))
				{
					/* ----------------
					 *	if there is nothing in the input buffer, don't bother
					 *	trying to parse and execute anything..
					 * ----------------
					 */
					IsEmptyQuery = true;
				}
				else
				{
					/* ----------------
					 *	otherwise, process the input string.
					 * ----------------
					 */
					IsEmptyQuery = false;
					if (ShowStats)
						ResetUsage();

					/* start an xact for this query */
					if (Verbose)
						TPRINTF(TRACE_VERBOSE, "StartTransactionCommand");
					StartTransactionCommand();

					pg_exec_query(parser_input);

					if (ShowStats)
						ShowUsage();
				}
				break;

				/* ----------------
				 *	'X' means that the frontend is closing down the socket
				 * ----------------
				 */
			case 'X':
				pq_close();
				proc_exit(0);
				break;

			default:
				elog(ERROR, "unknown frontend message was received");
		}

		/* ----------------
		 *	 (6) commit the current transaction
		 *
		 *	 Note: if we had an empty input buffer, then we didn't
		 *	 call pg_exec_query, so we don't bother to commit this transaction.
		 * ----------------
		 */
		if (!IsEmptyQuery)
		{
			if (Verbose)
				TPRINTF(TRACE_VERBOSE, "CommitTransactionCommand");
			PS_SET_STATUS("commit");
			CommitTransactionCommand();
		}
		else
		{
			if (IsUnderPostmaster)
				NullCommand(Remote);
		}
	}							/* infinite for-loop */

	proc_exit(0);				/* shouldn't get here... */
	return 1;
}

#ifndef HAVE_GETRUSAGE
#include "rusagestub.h"
#else							/* HAVE_GETRUSAGE */
#include <sys/resource.h>
#endif	 /* HAVE_GETRUSAGE */

struct rusage Save_r;
struct timeval Save_t;

void
ResetUsage(void)
{
	struct timezone tz;

	getrusage(RUSAGE_SELF, &Save_r);
	gettimeofday(&Save_t, &tz);
	ResetBufferUsage();
/*	  ResetTupleCount(); */
}

void
ShowUsage(void)
{
	struct timeval user,
				sys;
	struct timeval elapse_t;
	struct timezone tz;
	struct rusage r;

	getrusage(RUSAGE_SELF, &r);
	gettimeofday(&elapse_t, &tz);
	memmove((char *) &user, (char *) &r.ru_utime, sizeof(user));
	memmove((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.
	 */

	fprintf(StatFp, "! system usage stats:\n");
	fprintf(StatFp,
			"!\t%ld.%06ld elapsed %ld.%06ld user %ld.%06ld system sec\n",
			(long int) elapse_t.tv_sec - Save_t.tv_sec,
			(long int) elapse_t.tv_usec - Save_t.tv_usec,
			(long int) r.ru_utime.tv_sec - Save_r.ru_utime.tv_sec,
			(long int) r.ru_utime.tv_usec - Save_r.ru_utime.tv_usec,
			(long int) r.ru_stime.tv_sec - Save_r.ru_stime.tv_sec,
			(long int) r.ru_stime.tv_usec - Save_r.ru_stime.tv_usec);
	fprintf(StatFp,
			"!\t[%ld.%06ld user %ld.%06ld sys total]\n",
			(long int) user.tv_sec,
			(long int) user.tv_usec,
			(long int) sys.tv_sec,
			(long int) sys.tv_usec);
#ifdef HAVE_GETRUSAGE
	fprintf(StatFp,
			"!\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);
	fprintf(StatFp,
		  "!\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);
	fprintf(StatFp,
	 "!\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);
	fprintf(StatFp,
		 "!\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 */
	fprintf(StatFp, "! postgres usage stats:\n");
	PrintBufferUsage(StatFp);
/*	   DisplayTupleCount(StatFp); */
}

#ifdef USE_ASSERT_CHECKING
int
assertEnable(int val)
{
	assert_enabled = val;
	return val;
}

#ifdef ASSERT_CHECKING_TEST
int
assertTest(int val)
{
	Assert(val == 0);

	if (assert_enabled)
	{
		/* val != 0 should be trapped by previous Assert */
		elog(NOTICE, "Assert test successfull (val = %d)", val);
	}
	else
		elog(NOTICE, "Assert checking is disabled (val = %d)", val);

	return val;
}

#endif
#endif