From d75b2ec4ebbc7fdb51088e89da47c6523bf2c640 Mon Sep 17 00:00:00 2001
From: Bruce Momjian <bruce@momjian.us>
Date: Sat, 20 Dec 2003 17:31:21 +0000
Subject: [PATCH] This patch is the next step towards (re)allowing fork/exec.

Claudio Natoli
---
 src/backend/access/transam/xlog.c         |  27 +-
 src/backend/bootstrap/bootstrap.c         |   7 +-
 src/backend/postmaster/pgstat.c           |   4 +-
 src/backend/postmaster/postmaster.c       | 286 +++++++++++++++++-----
 src/backend/storage/buffer/buf_init.c     |   6 +-
 src/backend/storage/file/fd.c             |  15 +-
 src/backend/storage/freespace/freespace.c |  22 +-
 src/backend/storage/ipc/ipci.c            |  28 ++-
 src/backend/storage/ipc/pmsignal.c        |   6 +-
 src/backend/storage/ipc/shmem.c           | 133 ++++++----
 src/backend/storage/ipc/sinvaladt.c       |   7 +-
 src/backend/storage/lmgr/lock.c           |  48 ++--
 src/backend/storage/lmgr/lwlock.c         |   4 +-
 src/backend/storage/lmgr/proc.c           |   5 +-
 src/backend/tcop/postgres.c               |  61 +++--
 src/include/access/xlogdefs.h             |   9 +-
 src/include/c.h                           |   9 +-
 src/include/libpq/libpq-be.h              |   8 +-
 src/include/storage/fd.h                  |   6 +-
 src/include/storage/ipc.h                 |   4 +-
 src/include/storage/lock.h                |   4 +-
 src/include/storage/lwlock.h              |   3 +-
 src/include/storage/shmem.h               |   4 +-
 23 files changed, 490 insertions(+), 216 deletions(-)

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 794e392f78..1f8eb50795 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.128 2003/12/14 00:34:47 neilc Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.129 2003/12/20 17:31:20 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -166,7 +166,7 @@ XLogRecPtr	ProcLastRecEnd = {0, 0};
  * to update from XLogCtl->Insert.RedoRecPtr if we hold the info_lck;
  * see GetRedoRecPtr.
  */
-static XLogRecPtr RedoRecPtr;
+NON_EXEC_STATIC XLogRecPtr RedoRecPtr;
 
 /*----------
  * Shared-memory data structures for XLOG control
@@ -231,12 +231,6 @@ typedef struct XLogwrtRqst
 	XLogRecPtr	Flush;			/* last byte + 1 to flush */
 } XLogwrtRqst;
 
-typedef struct XLogwrtResult
-{
-	XLogRecPtr	Write;			/* last byte + 1 written out */
-	XLogRecPtr	Flush;			/* last byte + 1 flushed */
-} XLogwrtResult;
-
 /*
  * Shared state data for XLogInsert.
  */
@@ -404,7 +398,7 @@ static char ControlFilePath[MAXPGPATH];
  * Private, possibly out-of-date copy of shared LogwrtResult.
  * See discussion above.
  */
-static XLogwrtResult LogwrtResult = {{0, 0}, {0, 0}};
+NON_EXEC_STATIC XLogwrtResult LogwrtResult = {{0, 0}, {0, 0}};
 
 /*
  * openLogFile is -1 or a kernel FD for an open log file segment.
@@ -2398,7 +2392,7 @@ XLOGShmemSize(void)
 void
 XLOGShmemInit(void)
 {
-	bool		found;
+	bool		foundXLog, foundCFile;
 
 	/* this must agree with space requested by XLOGShmemSize() */
 	if (XLOGbuffers < MinXLOGbuffers)
@@ -2409,11 +2403,16 @@ XLOGShmemInit(void)
 						MAXALIGN(sizeof(XLogCtlData) +
 								 sizeof(XLogRecPtr) * XLOGbuffers)
 						+ BLCKSZ * XLOGbuffers,
-						&found);
-	Assert(!found);
+						&foundXLog);
 	ControlFile = (ControlFileData *)
-		ShmemInitStruct("Control File", sizeof(ControlFileData), &found);
-	Assert(!found);
+		ShmemInitStruct("Control File", sizeof(ControlFileData), &foundCFile);
+
+	if (foundXLog || foundCFile)
+	{
+		/* both should be present or neither */
+		Assert(foundXLog && foundCFile);
+		return;
+	}
 
 	memset(XLogCtl, 0, sizeof(XLogCtlData));
 
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index 94daf94355..4820582eb3 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/bootstrap/bootstrap.c,v 1.170 2003/12/12 18:45:08 petere Exp $
+ *	  $PostgreSQL: pgsql/src/backend/bootstrap/bootstrap.c,v 1.171 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -347,9 +347,10 @@ BootstrapMain(int argc, char *argv[])
 	if (!dbname || argc != optind)
 		usage();
 
-
-	if (IsUnderPostmaster && ExecBackend && MyProc /* ordinary backend */ )
+#ifdef EXEC_BACKEND
+	if (IsUnderPostmaster && MyProc /* ordinary backend */ )
 		AttachSharedMemoryAndSemaphores();
+#endif
 
 	if (!IsUnderPostmaster /* when exec || ExecBackend */ )
 	{
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 7eef116303..38323f45ba 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -13,7 +13,7 @@
  *
  *	Copyright (c) 2001-2003, PostgreSQL Global Development Group
  *
- *	$PostgreSQL: pgsql/src/backend/postmaster/pgstat.c,v 1.48 2003/11/29 19:51:55 pgsql Exp $
+ *	$PostgreSQL: pgsql/src/backend/postmaster/pgstat.c,v 1.49 2003/12/20 17:31:21 momjian Exp $
  * ----------
  */
 #include "postgres.h"
@@ -71,7 +71,7 @@ bool		pgstat_is_running = false;
  * Local data
  * ----------
  */
-static int	pgStatSock = -1;
+NON_EXEC_STATIC int	pgStatSock = -1;
 static int	pgStatPipe[2];
 static struct sockaddr_storage pgStatAddr;
 static int	pgStatPmPipe[2] = {-1, -1};
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index b17ade7376..f0560ce6f7 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -37,7 +37,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.351 2003/12/01 22:15:37 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/postmaster/postmaster.c,v 1.352 2003/12/20 17:31:21 momjian Exp $
  *
  * NOTES
  *
@@ -273,6 +273,7 @@ static void dummy_handler(SIGNAL_ARGS);
 static void CleanupProc(int pid, int exitstatus);
 static void LogChildExit(int lev, const char *procname,
 			 int pid, int exitstatus);
+NON_EXEC_STATIC bool BackendInit(Port *port);
 static int	BackendFork(Port *port);
 static void ExitPostmaster(int status);
 static void usage(const char *);
@@ -282,10 +283,6 @@ static int	ProcessStartupPacket(Port *port, bool SSLdone);
 static void processCancelRequest(Port *port, void *pkt);
 static int	initMasks(fd_set *rmask);
 static void report_fork_failure_to_client(Port *port, int errnum);
-enum CAC_state
-{
-	CAC_OK, CAC_STARTUP, CAC_SHUTDOWN, CAC_RECOVERY, CAC_TOOMANY
-};
 static enum CAC_state canAcceptConnections(void);
 static long PostmasterRandom(void);
 static void RandomSalt(char *cryptSalt, char *md5Salt);
@@ -298,6 +295,11 @@ postmaster_error(const char *fmt,...)
 /* This lets gcc check the format string for consistency. */
 __attribute__((format(printf, 1, 2)));
 
+#ifdef EXEC_BACKEND
+static void
+write_backend_variables(pid_t pid, Port *port);
+#endif
+
 #define StartupDataBase()		SSDataBase(BS_XLOG_STARTUP)
 #define CheckPointDataBase()	SSDataBase(BS_XLOG_CHECKPOINT)
 #define StartBackgroundWriter()	SSDataBase(BS_XLOG_BGWRITER)
@@ -1185,7 +1187,6 @@ initMasks(fd_set *rmask)
 static int
 ProcessStartupPacket(Port *port, bool SSLdone)
 {
-	enum CAC_state cac;
 	int32		len;
 	void	   *buf;
 	ProtocolVersion proto;
@@ -1244,7 +1245,11 @@ ProcessStartupPacket(Port *port, bool SSLdone)
 
 	if (proto == CANCEL_REQUEST_CODE)
 	{
+#ifdef EXEC_BACKEND
+		abort(); /* FIXME: [fork/exec] Whoops. Not handled... yet */
+#else
 		processCancelRequest(port, buf);
+#endif
 		return 127;				/* XXX */
 	}
 
@@ -1435,9 +1440,7 @@ ProcessStartupPacket(Port *port, bool SSLdone)
 	 * so now instead of wasting cycles on an authentication exchange.
 	 * (This also allows a pg_ping utility to be written.)
 	 */
-	cac = canAcceptConnections();
-
-	switch (cac)
+	switch (port->canAcceptConnections)
 	{
 		case CAC_STARTUP:
 			ereport(FATAL,
@@ -1499,8 +1502,10 @@ processCancelRequest(Port *port, void *pkt)
 								 backendPID)));
 		return;
 	}
-	else if (ExecBackend)
+#ifdef EXEC_BACKEND
+	else
 		AttachSharedMemoryAndSemaphores();
+#endif
 
 	/* See if we have a matching backend */
 
@@ -2341,40 +2346,25 @@ split_opts(char **argv, int *argcp, char *s)
 	}
 }
 
+
 /*
- * BackendFork -- perform authentication, and if successful, set up the
- *		backend's argument list and invoke backend main().
- *
- * This used to perform an execv() but we no longer exec the backend;
- * it's the same executable as the postmaster.
+ * BackendInit/Fork -- perform authentication [BackendInit], and if successful,
+ *              set up the backend's argument list [BackendFork] and invoke
+ *              backend main() [or exec in EXEC_BACKEND case]
  *
  * returns:
  *		Shouldn't return at all.
  *		If PostgresMain() fails, return status.
  */
-static int
-BackendFork(Port *port)
+NON_EXEC_STATIC bool
+BackendInit(Port *port)
 {
-	char	  **av;
-	int			maxac;
-	int			ac;
-	char		debugbuf[32];
-	char		protobuf[32];
-
-#ifdef EXEC_BACKEND
-	char		pbuf[NAMEDATALEN + 256];
-#endif
-	int			i;
 	int			status;
 	struct timeval now;
 	struct timezone tz;
 	char		remote_host[NI_MAXHOST];
 	char		remote_port[NI_MAXSERV];
 
-	/*
-	 * Let's clean up ourselves as the postmaster child
-	 */
-
 	IsUnderPostmaster = true;	/* we are a postmaster subprocess now */
 
 	ClientAuthInProgress = true;	/* limit visibility of log messages */
@@ -2386,9 +2376,6 @@ BackendFork(Port *port)
 	 * Signal handlers setting is moved to tcop/postgres...
 	 */
 
-	/* Close the postmaster's other sockets */
-	ClosePostmasterPorts(true);
-
 	/* Save port etc. for ps status */
 	MyProcPort = port;
 
@@ -2444,16 +2431,6 @@ BackendFork(Port *port)
 		StrNCpy(remote_host, tmphost, sizeof(remote_host));
 	}
 
-	/*
-	 * PreAuthDelay is a debugging aid for investigating problems in the
-	 * authentication cycle: it can be set in postgresql.conf to allow
-	 * time to attach to the newly-forked backend with a debugger. (See
-	 * also the -W backend switch, which we allow clients to pass through
-	 * PGOPTIONS, but it is not honored until after authentication.)
-	 */
-	if (PreAuthDelay > 0)
-		sleep(PreAuthDelay);
-
 	/*
 	 * Ready to begin client interaction.  We will give up and exit(0)
 	 * after a time delay, so that a broken client can't hog a connection
@@ -2469,7 +2446,7 @@ BackendFork(Port *port)
 	status = ProcessStartupPacket(port, false);
 
 	if (status != STATUS_OK)
-		return 0;				/* cancel request processed, or error */
+		return false;				/* cancel request processed, or error */
 
 	/*
 	 * Now that we have the user and database name, we can set the process
@@ -2506,6 +2483,50 @@ BackendFork(Port *port)
 	gettimeofday(&now, &tz);
 	srandom((unsigned int) now.tv_usec);
 
+#ifdef EXEC_BACKEND
+	ClientAuthInProgress = false;		/* client_min_messages is active
+										 * now */
+#endif
+	return true;
+}
+
+
+static int
+BackendFork(Port *port)
+{
+	char	  **av;
+	int			maxac;
+	int			ac;
+	char		debugbuf[32];
+#ifndef EXEC_BACKEND
+	char		protobuf[32];
+#endif
+	int			i;
+	char tmpExtraOptions[MAXPGPATH];
+
+	/*
+	 * Let's clean up ourselves as the postmaster child, and
+	 * close the postmaster's other sockets
+	 */
+	ClosePostmasterPorts(true);
+
+	/*
+	 * PreAuthDelay is a debugging aid for investigating problems in the
+	 * authentication cycle: it can be set in postgresql.conf to allow
+	 * time to attach to the newly-forked backend with a debugger. (See
+	 * also the -W backend switch, which we allow clients to pass through
+	 * PGOPTIONS, but it is not honored until after authentication.)
+	 */
+	if (PreAuthDelay > 0)
+		sleep(PreAuthDelay);
+
+	port->canAcceptConnections = canAcceptConnections();
+
+#ifndef EXEC_BACKEND
+	if (!BackendInit(port))
+		return -1;
+#endif
+
 	/* ----------------
 	 * Now, build the argv vector that will be given to PostgresMain.
 	 *
@@ -2540,30 +2561,38 @@ BackendFork(Port *port)
 
 	/*
 	 * Pass any backend switches specified with -o in the postmaster's own
-	 * command line.  We assume these are secure. (It's OK to mangle
-	 * ExtraOptions since we are now in the child process; this won't
-	 * change the postmaster's copy.)
+	 * command line.  We assume these are secure.
+	 * [Note: now makes a copy to protect against future fork/exec changes]
 	 */
-	split_opts(av, &ac, ExtraOptions);
+	strcpy(tmpExtraOptions,ExtraOptions);
+	split_opts(av, &ac, tmpExtraOptions);
 
+#ifndef EXEC_BACKEND
 	/* Tell the backend what protocol the frontend is using. */
 	snprintf(protobuf, sizeof(protobuf), "-v%u", port->proto);
 	av[ac++] = protobuf;
+#endif
 
 	/*
 	 * Tell the backend it is being called from the postmaster, and which
 	 * database to use.  -p marks the end of secure switches.
 	 */
-	av[ac++] = "-p";
 #ifdef EXEC_BACKEND
-	Assert(UsedShmemSegID != 0 && UsedShmemSegAddr != NULL);
-	/* database name at the end because it might contain commas */
-	snprintf(pbuf, sizeof(pbuf), "%d,%d,%lu,%p,%s",
-			 port->sock, canAcceptConnections(),
-			 UsedShmemSegID, UsedShmemSegAddr,
-			 port->database_name);
-	av[ac++] = pbuf;
+	write_backend_variables(getpid(),port);
+
+	/* pass data dir before end of secure switches (-p) */
+	av[ac++] = "-D";
+	av[ac++] = DataDir;
+
+	/*
+	 * This is totally bogus. We need to pass an arg to -p, but we'll
+	 * actually get the dbname by ProcessStartupPacket in the exec'd
+	 * process
+	 */
+	av[ac++] = "-p";
+	av[ac++] = "FORK_EXEC";
 #else
+	av[ac++] = "-p";
 	av[ac++] = port->database_name;
 #endif
 
@@ -2571,6 +2600,10 @@ BackendFork(Port *port)
 	 * Pass the (insecure) option switches from the connection request.
 	 * (It's OK to mangle port->cmdline_options now.)
 	 */
+	/* FIXME: [fork/exec] Hmmm.. we won't see these until after we BackendInit.
+	 * Should we add code to BackendInit to add these (somehow!) into
+	 * the PostgresMain argument list in the EXEC_BACKEND case?
+	 */
 	if (port->cmdline_options)
 		split_opts(av, &ac, port->cmdline_options);
 
@@ -2594,17 +2627,21 @@ BackendFork(Port *port)
 	 */
 	ereport(DEBUG3,
 			(errmsg_internal("%s child[%d]: starting with (",
-							 progname, MyProcPid)));
+							 progname, getpid())));
 	for (i = 0; i < ac; ++i)
 		ereport(DEBUG3,
 				(errmsg_internal("\t%s", av[i])));
 	ereport(DEBUG3,
 			(errmsg_internal(")")));
 
+#ifdef EXEC_BACKEND
+	return execv(pg_pathname,av);
+#else
 	ClientAuthInProgress = false;		/* client_min_messages is active
 										 * now */
 
 	return (PostgresMain(ac, av, port->user_name));
+#endif
 }
 
 /*
@@ -3051,3 +3088,136 @@ postmaster_error(const char *fmt,...)
 	va_end(ap);
 	fprintf(stderr, "\n");
 }
+
+
+#ifdef EXEC_BACKEND
+
+/*
+ * The following need to be available to the read/write_backend_variables
+ * functions
+ */
+extern XLogRecPtr RedoRecPtr;
+extern XLogwrtResult LogwrtResult;
+extern slock_t *ShmemLock;
+extern slock_t *ShmemIndexLock;
+extern void *ShmemIndexAlloc;
+typedef struct LWLock LWLock;
+extern LWLock *LWLockArray;
+extern slock_t  *ProcStructLock;
+extern int	pgStatSock;
+
+#define write_var(var,fp) fwrite((void*)&(var),sizeof(var),1,fp)
+#define read_var(var,fp)  fread((void*)&(var),sizeof(var),1,fp);
+#define get_tmp_backend_file_name(buf,id)	\
+		do {								\
+			Assert(DataDir);				\
+			sprintf((buf),					\
+				"%s/%s/%s.backend_var.%d",	\
+				DataDir,					\
+				PG_TEMP_FILES_DIR,			\
+				PG_TEMP_FILE_PREFIX,		\
+				(id));						\
+		} while (0)
+
+static void
+write_backend_variables(pid_t pid, Port *port)
+{
+	char	filename[MAXPGPATH];
+	FILE	*fp;
+	get_tmp_backend_file_name(filename,pid);
+
+	/* Open file */
+	fp = AllocateFile(filename, PG_BINARY_W);
+	if (!fp)
+	{
+		/* As per OpenTemporaryFile... */
+		char dirname[MAXPGPATH];
+		sprintf(dirname,"%s/%s",DataDir,PG_TEMP_FILES_DIR);
+		mkdir(dirname, S_IRWXU);
+
+		fp = AllocateFile(filename, PG_BINARY_W);
+		if (!fp)
+		{
+			ereport(ERROR,
+				(errcode_for_file_access(),
+				errmsg("could not write to file \"%s\": %m", filename)));
+			return;
+		}
+	}
+
+	/* Write vars */
+	write_var(port->sock,fp);
+	write_var(port->proto,fp);
+	write_var(port->laddr,fp);
+	write_var(port->raddr,fp);
+	write_var(port->canAcceptConnections,fp);
+	write_var(MyCancelKey,fp);
+
+	write_var(RedoRecPtr,fp);
+	write_var(LogwrtResult,fp);
+
+	write_var(UsedShmemSegID,fp);
+	write_var(UsedShmemSegAddr,fp);
+
+	write_var(ShmemLock,fp);
+	write_var(ShmemIndexLock,fp);
+	write_var(ShmemVariableCache,fp);
+	write_var(ShmemIndexAlloc,fp);
+
+	write_var(LWLockArray,fp);
+	write_var(ProcStructLock,fp);
+	write_var(pgStatSock,fp);
+
+	/* Release file */
+	FreeFile(fp);
+}
+
+void
+read_backend_variables(pid_t pid, Port *port)
+{
+	char	filename[MAXPGPATH];
+	FILE	*fp;
+	get_tmp_backend_file_name(filename,pid);
+
+	/* Open file */
+	fp = AllocateFile(filename, PG_BINARY_R);
+	if (!fp)
+	{
+		ereport(ERROR,
+			(errcode_for_file_access(),
+			errmsg("could not read from backend_variables file \"%s\": %m", filename)));
+		return;
+	}
+
+	/* Read vars */
+	read_var(port->sock,fp);
+	read_var(port->proto,fp);
+	read_var(port->laddr,fp);
+	read_var(port->raddr,fp);
+	read_var(port->canAcceptConnections,fp);
+	read_var(MyCancelKey,fp);
+
+	read_var(RedoRecPtr,fp);
+	read_var(LogwrtResult,fp);
+
+	read_var(UsedShmemSegID,fp);
+	read_var(UsedShmemSegAddr,fp);
+
+	read_var(ShmemLock,fp);
+	read_var(ShmemIndexLock,fp);
+	read_var(ShmemVariableCache,fp);
+	read_var(ShmemIndexAlloc,fp);
+
+	read_var(LWLockArray,fp);
+	read_var(ProcStructLock,fp);
+	read_var(pgStatSock,fp);
+
+	/* Release file */
+	FreeFile(fp);
+	if (unlink(filename) != 0)
+		ereport(WARNING,
+				(errcode_for_file_access(),
+				 errmsg("could not remove file \"%s\": %m", filename)));
+}
+
+#endif
diff --git a/src/backend/storage/buffer/buf_init.c b/src/backend/storage/buffer/buf_init.c
index 1c66b950a5..1a707568b5 100644
--- a/src/backend/storage/buffer/buf_init.c
+++ b/src/backend/storage/buffer/buf_init.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/buffer/buf_init.c,v 1.59 2003/12/14 00:34:47 neilc Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/buffer/buf_init.c,v 1.60 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -125,7 +125,9 @@ InitBufferPool(void)
 	 * anyone else attached to the shmem at this point, we've got
 	 * problems.
 	 */
+#ifndef EXEC_BACKEND
 	LWLockAcquire(BufMgrLock, LW_EXCLUSIVE);
+#endif
 
 	BufferDescriptors = (BufferDesc *)
 		ShmemInitStruct("Buffer Descriptors",
@@ -177,7 +179,9 @@ InitBufferPool(void)
 	/* Init other shared buffer-management stuff */
 	StrategyInitialize(!foundDescs);
 
+#ifndef EXEC_BACKEND
 	LWLockRelease(BufMgrLock);
+#endif
 }
 
 /*
diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index 78814d77b6..4875b7f2bc 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/file/fd.c,v 1.104 2003/12/12 18:45:09 petere Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/file/fd.c,v 1.105 2003/12/20 17:31:21 momjian Exp $
  *
  * NOTES:
  *
@@ -53,11 +53,6 @@
 #include "storage/ipc.h"
 
 
-/* Filename components for OpenTemporaryFile */
-#define PG_TEMP_FILES_DIR "pgsql_tmp"
-#define PG_TEMP_FILE_PREFIX "pgsql_tmp"
-
-
 /*
  * Problem: Postgres does a system(ld...) to do dynamic loading.
  * This will open several extra files in addition to those used by
@@ -1217,8 +1212,12 @@ RemovePgTempFiles(void)
 	{
 		while ((db_de = readdir(db_dir)) != NULL)
 		{
-			if (strcmp(db_de->d_name, ".") == 0 ||
-				strcmp(db_de->d_name, "..") == 0)
+			if (strcmp(db_de->d_name, ".") == 0
+#ifndef EXEC_BACKEND
+			/* no PG_TEMP_FILES_DIR in DataDir in non EXEC_BACKEND case */
+				|| strcmp(db_de->d_name, "..") == 0
+#endif
+			)
 				continue;
 
 			snprintf(temp_path, sizeof(temp_path),
diff --git a/src/backend/storage/freespace/freespace.c b/src/backend/storage/freespace/freespace.c
index a7bffb5c73..84f5c65c92 100644
--- a/src/backend/storage/freespace/freespace.c
+++ b/src/backend/storage/freespace/freespace.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/freespace/freespace.c,v 1.27 2003/12/12 18:45:09 petere Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/freespace/freespace.c,v 1.28 2003/12/20 17:31:21 momjian Exp $
  *
  *
  * NOTES:
@@ -180,7 +180,6 @@ typedef struct FSMRelation FSMRelation;
 /* Header for whole map */
 struct FSMHeader
 {
-	HTAB	   *relHash;		/* hashtable of FSMRelation entries */
 	FSMRelation *usageList;		/* FSMRelations in usage-recency order */
 	FSMRelation *usageListTail; /* tail of usage-recency list */
 	FSMRelation *firstRel;		/* FSMRelations in arena storage order */
@@ -218,6 +217,7 @@ int			MaxFSMRelations;	/* these are set by guc.c */
 int			MaxFSMPages;
 
 static FSMHeader *FreeSpaceMap; /* points to FSMHeader in shared memory */
+static HTAB	*FreeSpaceMapRelHash; /* points to (what used to be) FSMHeader->relHash */
 
 
 static FSMRelation *lookup_fsm_rel(RelFileNode *rel);
@@ -265,13 +265,15 @@ InitFreeSpaceMap(void)
 {
 	HASHCTL		info;
 	int			nchunks;
+	bool found;
 
 	/* Create table header */
-	FreeSpaceMap = (FSMHeader *) ShmemAlloc(sizeof(FSMHeader));
+	FreeSpaceMap = (FSMHeader *) ShmemInitStruct("Free Space Map Header",sizeof(FSMHeader),&found);
 	if (FreeSpaceMap == NULL)
 		ereport(FATAL,
 				(errcode(ERRCODE_OUT_OF_MEMORY),
 			   errmsg("insufficient shared memory for free space map")));
+	if (!found)
 	MemSet(FreeSpaceMap, 0, sizeof(FSMHeader));
 
 	/* Create hashtable for FSMRelations */
@@ -279,17 +281,21 @@ InitFreeSpaceMap(void)
 	info.entrysize = sizeof(FSMRelation);
 	info.hash = tag_hash;
 
-	FreeSpaceMap->relHash = ShmemInitHash("Free Space Map Hash",
+	FreeSpaceMapRelHash = ShmemInitHash("Free Space Map Hash",
 										  MaxFSMRelations / 10,
 										  MaxFSMRelations,
 										  &info,
 										  (HASH_ELEM | HASH_FUNCTION));
 
-	if (!FreeSpaceMap->relHash)
+	if (!FreeSpaceMapRelHash)
 		ereport(FATAL,
 				(errcode(ERRCODE_OUT_OF_MEMORY),
 			   errmsg("insufficient shared memory for free space map")));
 
+	if (found)
+		return;
+
+
 	/* Allocate page-storage arena */
 	nchunks = (MaxFSMPages - 1) / CHUNKPAGES + 1;
 	/* This check ensures spareChunks will be greater than zero */
@@ -974,7 +980,7 @@ lookup_fsm_rel(RelFileNode *rel)
 {
 	FSMRelation *fsmrel;
 
-	fsmrel = (FSMRelation *) hash_search(FreeSpaceMap->relHash,
+	fsmrel = (FSMRelation *) hash_search(FreeSpaceMapRelHash,
 										 (void *) rel,
 										 HASH_FIND,
 										 NULL);
@@ -995,7 +1001,7 @@ create_fsm_rel(RelFileNode *rel)
 	FSMRelation *fsmrel;
 	bool		found;
 
-	fsmrel = (FSMRelation *) hash_search(FreeSpaceMap->relHash,
+	fsmrel = (FSMRelation *) hash_search(FreeSpaceMapRelHash,
 										 (void *) rel,
 										 HASH_ENTER,
 										 &found);
@@ -1050,7 +1056,7 @@ delete_fsm_rel(FSMRelation *fsmrel)
 	unlink_fsm_rel_usage(fsmrel);
 	unlink_fsm_rel_storage(fsmrel);
 	FreeSpaceMap->numRels--;
-	result = (FSMRelation *) hash_search(FreeSpaceMap->relHash,
+	result = (FSMRelation *) hash_search(FreeSpaceMapRelHash,
 										 (void *) &(fsmrel->key),
 										 HASH_REMOVE,
 										 NULL);
diff --git a/src/backend/storage/ipc/ipci.c b/src/backend/storage/ipc/ipci.c
index 982846843a..eaf22a095f 100644
--- a/src/backend/storage/ipc/ipci.c
+++ b/src/backend/storage/ipc/ipci.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.59 2003/12/01 21:59:25 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/ipc/ipci.c,v 1.60 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -87,7 +87,7 @@ CreateSharedMemoryAndSemaphores(bool makePrivate,
 	/*
 	 * Set up shared memory allocation mechanism
 	 */
-	InitShmemAllocation(seghdr);
+	InitShmemAllocation(seghdr, true);
 
 	/*
 	 * Now initialize LWLocks, which do shared memory allocation and are
@@ -135,12 +135,36 @@ CreateSharedMemoryAndSemaphores(bool makePrivate,
 }
 
 
+#ifdef EXEC_BACKEND
 /*
  * AttachSharedMemoryAndSemaphores
  *		Attaches to the existing shared resources.
  */
+
+/* FIXME: [fork/exec] This function is starting to look pretty much like
+	CreateSharedMemoryAndSemaphores. Refactor? */
 void
 AttachSharedMemoryAndSemaphores(void)
 {
+	PGShmemHeader *seghdr = PGSharedMemoryCreate(-1,false,-1);
+
+	InitShmemAllocation(seghdr, false);
+
+	InitShmemIndex();
+
+	XLOGShmemInit();
 	CLOGShmemInit();
+	InitBufferPool();
+
+	InitLocks();
+	InitLockTable(MaxBackends);
+
+	InitProcGlobal(MaxBackends);
+
+	CreateSharedInvalidationState(MaxBackends);
+
+	InitFreeSpaceMap();
+
+	PMSignalInit();
 }
+#endif
diff --git a/src/backend/storage/ipc/pmsignal.c b/src/backend/storage/ipc/pmsignal.c
index 6545c748d3..fb2b2faca0 100644
--- a/src/backend/storage/ipc/pmsignal.c
+++ b/src/backend/storage/ipc/pmsignal.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/ipc/pmsignal.c,v 1.6 2003/11/29 19:51:56 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/ipc/pmsignal.c,v 1.7 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -44,9 +44,11 @@ static volatile sig_atomic_t *PMSignalFlags;
 void
 PMSignalInit(void)
 {
+	bool found;
 	PMSignalFlags = (sig_atomic_t *)
-		ShmemAlloc(NUM_PMSIGNALS * sizeof(sig_atomic_t));
+		ShmemInitStruct("PMSignalFlags",NUM_PMSIGNALS * sizeof(sig_atomic_t),&found);
 
+	if (!found)
 	MemSet(PMSignalFlags, 0, NUM_PMSIGNALS * sizeof(sig_atomic_t));
 }
 
diff --git a/src/backend/storage/ipc/shmem.c b/src/backend/storage/ipc/shmem.c
index b4e1439d15..598597f0aa 100644
--- a/src/backend/storage/ipc/shmem.c
+++ b/src/backend/storage/ipc/shmem.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/ipc/shmem.c,v 1.74 2003/11/29 19:51:56 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/ipc/shmem.c,v 1.75 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -74,7 +74,11 @@ SHMEM_OFFSET ShmemBase;			/* start address of shared memory */
 
 static SHMEM_OFFSET ShmemEnd;	/* end+1 address of shared memory */
 
-static slock_t *ShmemLock;		/* spinlock for shared memory allocation */
+NON_EXEC_STATIC slock_t *ShmemLock;		/* spinlock for shared memory allocation */
+
+NON_EXEC_STATIC slock_t *ShmemIndexLock;		/* spinlock for ShmemIndex */
+
+NON_EXEC_STATIC void *ShmemIndexAlloc = NULL; /* Memory actually allocated for ShmemIndex */
 
 static HTAB *ShmemIndex = NULL; /* primary index hashtable for shmem */
 
@@ -88,7 +92,7 @@ static bool ShmemBootstrap = false;		/* bootstrapping shmem index? */
  * but we use void to avoid having to include ipc.h in shmem.h.
  */
 void
-InitShmemAllocation(void *seghdr)
+InitShmemAllocation(void *seghdr, bool init)
 {
 	PGShmemHeader *shmhdr = (PGShmemHeader *) seghdr;
 
@@ -97,26 +101,34 @@ InitShmemAllocation(void *seghdr)
 	ShmemBase = (SHMEM_OFFSET) shmhdr;
 	ShmemEnd = ShmemBase + shmhdr->totalsize;
 
-	/*
-	 * Initialize the spinlock used by ShmemAlloc.	We have to do the
-	 * space allocation the hard way, since ShmemAlloc can't be called
-	 * yet.
-	 */
-	ShmemLock = (slock_t *) (((char *) shmhdr) + shmhdr->freeoffset);
-	shmhdr->freeoffset += MAXALIGN(sizeof(slock_t));
-	Assert(shmhdr->freeoffset <= shmhdr->totalsize);
+	if (init)
+	{
+		/*
+		 * Initialize the spinlocks used by ShmemAlloc/ShmemInitStruct. We
+		 * have to do the space allocation the hard way, since ShmemAlloc
+		 * can't be called yet.
+		 */
+		ShmemLock = (slock_t *) (((char *) shmhdr) + shmhdr->freeoffset);
+		shmhdr->freeoffset += MAXALIGN(sizeof(slock_t));
+		Assert(shmhdr->freeoffset <= shmhdr->totalsize);
 
-	SpinLockInit(ShmemLock);
+		ShmemIndexLock = (slock_t *) (((char *) shmhdr) + shmhdr->freeoffset);
+		shmhdr->freeoffset += MAXALIGN(sizeof(slock_t));
+		Assert(shmhdr->freeoffset <= shmhdr->totalsize);
 
-	/* ShmemIndex can't be set up yet (need LWLocks first) */
-	ShmemIndex = (HTAB *) NULL;
-
-	/*
-	 * Initialize ShmemVariableCache for transaction manager.
-	 */
-	ShmemVariableCache = (VariableCache)
+		SpinLockInit(ShmemLock);
+		SpinLockInit(ShmemIndexLock);
+	
+		/* ShmemIndex can't be set up yet (need LWLocks first) */
+		ShmemIndex = (HTAB *) NULL;
+	
+		/*
+		 * Initialize ShmemVariableCache for transaction manager.
+		 */
+		ShmemVariableCache = (VariableCache)
 		ShmemAlloc(sizeof(*ShmemVariableCache));
-	memset(ShmemVariableCache, 0, sizeof(*ShmemVariableCache));
+		memset(ShmemVariableCache, 0, sizeof(*ShmemVariableCache));
+	}
 }
 
 /*
@@ -218,25 +230,28 @@ InitShmemIndex(void)
 	/*
 	 * Now, create an entry in the hashtable for the index itself.
 	 */
-	MemSet(item.key, 0, SHMEM_INDEX_KEYSIZE);
-	strncpy(item.key, "ShmemIndex", SHMEM_INDEX_KEYSIZE);
-
-	result = (ShmemIndexEnt *)
-		hash_search(ShmemIndex, (void *) &item, HASH_ENTER, &found);
-	if (!result)
-		ereport(FATAL,
-				(errcode(ERRCODE_OUT_OF_MEMORY),
-				 errmsg("out of shared memory")));
-
-	Assert(ShmemBootstrap && !found);
-
-	result->location = MAKE_OFFSET(ShmemIndex->hctl);
-	result->size = SHMEM_INDEX_SIZE;
-
-	ShmemBootstrap = false;
+	if (!IsUnderPostmaster)
+	{
+		MemSet(item.key, 0, SHMEM_INDEX_KEYSIZE);
+		strncpy(item.key, "ShmemIndex", SHMEM_INDEX_KEYSIZE);
+	
+		result = (ShmemIndexEnt *)
+			hash_search(ShmemIndex, (void *) &item, HASH_ENTER, &found);
+		if (!result)
+			ereport(FATAL,
+					(errcode(ERRCODE_OUT_OF_MEMORY),
+					 errmsg("out of shared memory")));
+	
+		Assert(ShmemBootstrap && !found);
+	
+		result->location = MAKE_OFFSET(ShmemIndex->hctl);
+		result->size = SHMEM_INDEX_SIZE;
+	
+		ShmemBootstrap = false;
+	}
 
 	/* now release the lock acquired in ShmemInitStruct */
-	LWLockRelease(ShmemIndexLock);
+	SpinLockRelease(ShmemIndexLock);
 }
 
 /*
@@ -320,21 +335,33 @@ ShmemInitStruct(const char *name, Size size, bool *foundPtr)
 	strncpy(item.key, name, SHMEM_INDEX_KEYSIZE);
 	item.location = BAD_LOCATION;
 
-	LWLockAcquire(ShmemIndexLock, LW_EXCLUSIVE);
+	SpinLockAcquire(ShmemIndexLock);
 
 	if (!ShmemIndex)
 	{
-		/*
-		 * If the shmem index doesn't exist, we are bootstrapping: we must
-		 * be trying to init the shmem index itself.
-		 *
-		 * Notice that the ShmemIndexLock is held until the shmem index has
-		 * been completely initialized.
-		 */
-		Assert(strcmp(name, "ShmemIndex") == 0);
-		Assert(ShmemBootstrap);
-		*foundPtr = FALSE;
-		return ShmemAlloc(size);
+		if (IsUnderPostmaster)
+		{
+			/* Must be initializing a (non-standalone) backend */
+			Assert(strcmp(name, "ShmemIndex") == 0);
+			Assert(ShmemBootstrap);
+			Assert(ShmemIndexAlloc);
+			*foundPtr = TRUE;
+		}
+		else
+		{
+			/*
+			 * If the shmem index doesn't exist, we are bootstrapping: we must
+			 * be trying to init the shmem index itself.
+			 *
+			 * Notice that the ShmemIndexLock is held until the shmem index has
+			 * been completely initialized.
+			 */
+			Assert(strcmp(name, "ShmemIndex") == 0);
+			Assert(ShmemBootstrap);
+			*foundPtr = FALSE;
+			ShmemIndexAlloc = ShmemAlloc(size);
+		}
+		return ShmemIndexAlloc;
 	}
 
 	/* look it up in the shmem index */
@@ -343,7 +370,7 @@ ShmemInitStruct(const char *name, Size size, bool *foundPtr)
 
 	if (!result)
 	{
-		LWLockRelease(ShmemIndexLock);
+		SpinLockRelease(ShmemIndexLock);
 		ereport(ERROR,
 				(errcode(ERRCODE_OUT_OF_MEMORY),
 				 errmsg("out of shared memory")));
@@ -359,7 +386,7 @@ ShmemInitStruct(const char *name, Size size, bool *foundPtr)
 		 */
 		if (result->size != size)
 		{
-			LWLockRelease(ShmemIndexLock);
+			SpinLockRelease(ShmemIndexLock);
 
 			elog(WARNING, "ShmemIndex entry size is wrong");
 			/* let caller print its message too */
@@ -376,7 +403,7 @@ ShmemInitStruct(const char *name, Size size, bool *foundPtr)
 			/* out of memory */
 			Assert(ShmemIndex);
 			hash_search(ShmemIndex, (void *) &item, HASH_REMOVE, NULL);
-			LWLockRelease(ShmemIndexLock);
+			SpinLockRelease(ShmemIndexLock);
 
 			ereport(WARNING,
 					(errcode(ERRCODE_OUT_OF_MEMORY),
@@ -389,6 +416,6 @@ ShmemInitStruct(const char *name, Size size, bool *foundPtr)
 	}
 	Assert(ShmemIsValid((unsigned long) structPtr));
 
-	LWLockRelease(ShmemIndexLock);
+	SpinLockRelease(ShmemIndexLock);
 	return structPtr;
 }
diff --git a/src/backend/storage/ipc/sinvaladt.c b/src/backend/storage/ipc/sinvaladt.c
index ff26f9b86e..a50cc4601e 100644
--- a/src/backend/storage/ipc/sinvaladt.c
+++ b/src/backend/storage/ipc/sinvaladt.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/ipc/sinvaladt.c,v 1.53 2003/11/29 19:51:56 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/ipc/sinvaladt.c,v 1.54 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -50,10 +50,13 @@ SIBufferInit(int maxBackends)
 	int			segSize;
 	SISeg	   *segP;
 	int			i;
+	bool found;
 
 	/* Allocate space in shared memory */
 	segSize = SInvalShmemSize(maxBackends);
-	shmInvalBuffer = segP = (SISeg *) ShmemAlloc(segSize);
+	shmInvalBuffer = segP = (SISeg *) ShmemInitStruct("shmInvalBuffer",segSize,&found);
+	if (found)
+		return;
 
 	/* Clear message counters, save size of procState array */
 	segP->minMsgNum = 0;
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 6b450a1d35..8cb25b4ccd 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/lock.c,v 1.130 2003/12/01 21:59:25 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/lock.c,v 1.131 2003/12/20 17:31:21 momjian Exp $
  *
  * NOTES
  *	  Outside modules can create a lock table and acquire/release
@@ -153,9 +153,11 @@ PROCLOCK_PRINT(const char *where, const PROCLOCK *proclockP)
  * map from lock method id to the lock table structure
  */
 static LockMethod LockMethods[MAX_LOCK_METHODS];
-
+static HTAB*	LockMethodLockHash[MAX_LOCK_METHODS];
+static HTAB*	LockMethodProcLockHash[MAX_LOCK_METHODS];
 static int	NumLockMethods;
 
+
 /*
  * InitLocks -- Init the lock module.  Create a private data
  *		structure for constructing conflict masks.
@@ -245,8 +247,9 @@ LockMethodTableInit(char *tabName,
 	/*
 	 * Lock the LWLock for the table (probably not necessary here)
 	 */
+#ifndef EXEC_BACKEND
 	LWLockAcquire(LockMgrLock, LW_EXCLUSIVE);
-
+#endif
 	/*
 	 * no zero-th table
 	 */
@@ -279,15 +282,15 @@ LockMethodTableInit(char *tabName,
 	hash_flags = (HASH_ELEM | HASH_FUNCTION);
 
 	sprintf(shmemName, "%s (lock hash)", tabName);
-	newLockMethod->lockHash = ShmemInitHash(shmemName,
+	LockMethodLockHash[NumLockMethods-1] = ShmemInitHash(shmemName,
 											init_table_size,
 											max_table_size,
 											&info,
 											hash_flags);
 
-	if (!newLockMethod->lockHash)
+	if (!LockMethodLockHash[NumLockMethods-1])
 		elog(FATAL, "could not initialize lock table \"%s\"", tabName);
-	Assert(newLockMethod->lockHash->hash == tag_hash);
+	Assert(LockMethodLockHash[NumLockMethods-1]->hash == tag_hash);
 
 	/*
 	 * allocate a hash table for PROCLOCK structs.	This is used to store
@@ -299,20 +302,21 @@ LockMethodTableInit(char *tabName,
 	hash_flags = (HASH_ELEM | HASH_FUNCTION);
 
 	sprintf(shmemName, "%s (proclock hash)", tabName);
-	newLockMethod->proclockHash = ShmemInitHash(shmemName,
+	LockMethodProcLockHash[NumLockMethods-1] = ShmemInitHash(shmemName,
 												init_table_size,
 												max_table_size,
 												&info,
 												hash_flags);
 
-	if (!newLockMethod->proclockHash)
+	if (!LockMethodProcLockHash[NumLockMethods-1])
 		elog(FATAL, "could not initialize lock table \"%s\"", tabName);
 
 	/* init data structures */
 	LockMethodInit(newLockMethod, conflictsP, numModes);
 
+#ifndef EXEC_BACKEND
 	LWLockRelease(LockMgrLock);
-
+#endif
 	pfree(shmemName);
 
 	return newLockMethod->lockmethodid;
@@ -449,8 +453,8 @@ LockAcquire(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 	/*
 	 * Find or create a lock with this tag
 	 */
-	Assert(lockMethodTable->lockHash->hash == tag_hash);
-	lock = (LOCK *) hash_search(lockMethodTable->lockHash,
+	Assert(LockMethodLockHash[lockmethodid]->hash == tag_hash);
+	lock = (LOCK *) hash_search(LockMethodLockHash[lockmethodid],
 								(void *) locktag,
 								HASH_ENTER, &found);
 	if (!lock)
@@ -497,7 +501,7 @@ LockAcquire(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 	/*
 	 * Find or create a proclock entry with this tag
 	 */
-	proclockTable = lockMethodTable->proclockHash;
+	proclockTable = LockMethodProcLockHash[lockmethodid];
 	proclock = (PROCLOCK *) hash_search(proclockTable,
 										(void *) &proclocktag,
 										HASH_ENTER, &found);
@@ -988,8 +992,8 @@ LockRelease(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 	/*
 	 * Find a lock with this tag
 	 */
-	Assert(lockMethodTable->lockHash->hash == tag_hash);
-	lock = (LOCK *) hash_search(lockMethodTable->lockHash,
+	Assert(LockMethodLockHash[lockmethodid]->hash == tag_hash);
+	lock = (LOCK *) hash_search(LockMethodLockHash[lockmethodid],
 								(void *) locktag,
 								HASH_FIND, NULL);
 
@@ -1014,7 +1018,7 @@ LockRelease(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 	proclocktag.proc = MAKE_OFFSET(MyProc);
 	TransactionIdStore(xid, &proclocktag.xid);
 
-	proclockTable = lockMethodTable->proclockHash;
+	proclockTable = LockMethodProcLockHash[lockmethodid];
 	proclock = (PROCLOCK *) hash_search(proclockTable,
 										(void *) &proclocktag,
 										HASH_FIND_SAVE, NULL);
@@ -1086,8 +1090,8 @@ LockRelease(LOCKMETHODID lockmethodid, LOCKTAG *locktag,
 		 * if there's no one waiting in the queue, we just released the
 		 * last lock on this object. Delete it from the lock table.
 		 */
-		Assert(lockMethodTable->lockHash->hash == tag_hash);
-		lock = (LOCK *) hash_search(lockMethodTable->lockHash,
+		Assert(LockMethodLockHash[lockmethodid]->hash == tag_hash);
+		lock = (LOCK *) hash_search(LockMethodLockHash[lockmethodid],
 									(void *) &(lock->tag),
 									HASH_REMOVE,
 									NULL);
@@ -1269,7 +1273,7 @@ LockReleaseAll(LOCKMETHODID lockmethodid, PGPROC *proc,
 		/*
 		 * remove the proclock entry from the hashtable
 		 */
-		proclock = (PROCLOCK *) hash_search(lockMethodTable->proclockHash,
+		proclock = (PROCLOCK *) hash_search(LockMethodProcLockHash[lockmethodid],
 											(void *) proclock,
 											HASH_REMOVE,
 											NULL);
@@ -1287,8 +1291,8 @@ LockReleaseAll(LOCKMETHODID lockmethodid, PGPROC *proc,
 			 * lock object.
 			 */
 			LOCK_PRINT("LockReleaseAll: deleting", lock, 0);
-			Assert(lockMethodTable->lockHash->hash == tag_hash);
-			lock = (LOCK *) hash_search(lockMethodTable->lockHash,
+			Assert(LockMethodLockHash[lockmethodid]->hash == tag_hash);
+			lock = (LOCK *) hash_search(LockMethodLockHash[lockmethodid],
 										(void *) &(lock->tag),
 										HASH_REMOVE, NULL);
 			if (!lock)
@@ -1367,7 +1371,7 @@ GetLockStatusData(void)
 
 	LWLockAcquire(LockMgrLock, LW_EXCLUSIVE);
 
-	proclockTable = LockMethods[DEFAULT_LOCKMETHOD]->proclockHash;
+	proclockTable = LockMethodProcLockHash[DEFAULT_LOCKMETHOD];
 
 	data->nelements = i = proclockTable->hctl->nentries;
 
@@ -1480,7 +1484,7 @@ DumpAllLocks(void)
 	if (!lockMethodTable)
 		return;
 
-	proclockTable = lockMethodTable->proclockHash;
+	proclockTable = LockMethodProcLockHash[lockmethodid];
 
 	if (proc->waitLock)
 		LOCK_PRINT("DumpAllLocks: waiting on", proc->waitLock, 0);
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index 4142bb5198..efb3ac4a90 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -15,7 +15,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/lwlock.c,v 1.18 2003/11/29 19:51:57 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/lwlock.c,v 1.19 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -43,7 +43,7 @@ typedef struct LWLock
  * the pointer by fork from the postmaster.  LWLockIds are indexes into
  * the array.
  */
-static LWLock *LWLockArray = NULL;
+NON_EXEC_STATIC LWLock *LWLockArray = NULL;
 
 /* shared counter for dynamic allocation of LWLockIds */
 static int *LWLockCounter;
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index effe5ac524..a4bab87e24 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/proc.c,v 1.140 2003/12/12 18:45:09 petere Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/proc.c,v 1.141 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -66,7 +66,7 @@ PGPROC	   *MyProc = NULL;
  * relatively infrequently (only at backend startup or shutdown) and not for
  * very long, so a spinlock is okay.
  */
-static slock_t *ProcStructLock = NULL;
+NON_EXEC_STATIC slock_t *ProcStructLock = NULL;
 
 static PROC_HDR *ProcGlobal = NULL;
 
@@ -248,6 +248,7 @@ InitProcess(void)
 	MyProc->waitHolder = NULL;
 	SHMQueueInit(&(MyProc->procHolders));
 
+
 	/*
 	 * Arrange to clean up at backend exit.
 	 */
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 0162cdc2d4..66f6dc063c 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.379 2003/12/01 22:15:37 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.380 2003/12/20 17:31:21 momjian Exp $
  *
  * NOTES
  *	  this is the "main" module of the postgres backend and
@@ -68,6 +68,10 @@
 extern int	optind;
 extern char *optarg;
 
+#ifdef EXEC_BACKEND
+extern bool BackendInit(Port*);
+extern void read_backend_variables(pid_t, Port*);
+#endif
 
 /* ----------------
  *		global variables
@@ -2052,7 +2056,6 @@ PostgresMain(int argc, char *argv[], const char *username)
 	 * initialize globals (already done if under postmaster, but not if
 	 * standalone; cheap enough to do over)
 	 */
-
 	MyProcPid = getpid();
 
 	/*
@@ -2060,7 +2063,7 @@ PostgresMain(int argc, char *argv[], const char *username)
 	 *
 	 * If we are running under the postmaster, this is done already.
 	 */
-	if (!IsUnderPostmaster)
+	if (!IsUnderPostmaster /* when exec || ExecBackend */)
 		MemoryContextInit();
 
 	set_ps_display("startup");
@@ -2268,7 +2271,6 @@ PostgresMain(int argc, char *argv[], const char *username)
 				break;
 
 			case 'p':
-
 				/*
 				 * p - special flag passed if backend was forked by a
 				 * postmaster.
@@ -2276,23 +2278,11 @@ PostgresMain(int argc, char *argv[], const char *username)
 				if (secure)
 				{
 #ifdef EXEC_BACKEND
-					char	   *p;
-					int			i;
-					int			PMcanAcceptConnections; /* will eventually be
-														 * global or static,
-														 * when fork */
-
-					sscanf(optarg, "%d,%d,%lu,%p,",
-						   &MyProcPort->sock, &PMcanAcceptConnections,
-						   &UsedShmemSegID, &UsedShmemSegAddr);
-					/* Grab dbname as last param */
-					for (i = 0, p = optarg - 1; i < 4 && p; i++)
-						p = strchr(p + 1, ',');
-					if (i == 4 && p)
-						dbname = strdup(p + 1);
+					IsUnderPostmaster = true;
 #else
 					dbname = strdup(optarg);
 #endif
+
 					secure = false;		/* subsequent switches are NOT
 										 * secure */
 					ctx = PGC_BACKEND;
@@ -2477,7 +2467,7 @@ PostgresMain(int argc, char *argv[], const char *username)
 		SetConfigOption("log_statement_stats", "false", ctx, gucsource);
 	}
 
-	if (!IsUnderPostmaster)
+	if (!IsUnderPostmaster || ExecBackend)
 	{
 		if (!potential_DataDir)
 		{
@@ -2497,10 +2487,27 @@ PostgresMain(int argc, char *argv[], const char *username)
 	if (IsUnderPostmaster)
 	{
 #ifdef EXEC_BACKEND
+		Port *port =(Port*)malloc(sizeof(Port));
+		if (port == NULL)
+			ereport(ERROR,
+				(errcode(ERRCODE_OUT_OF_MEMORY),
+				errmsg("insufficient memory to allocate port")));
+
 		read_nondefault_variables();
+		read_backend_variables(getpid(),port);
+
+		/* FIXME: [fork/exec] Ugh */
+		load_hba();
+		load_ident();
+		load_user();
+		load_group();
+
+		if (!BackendInit(port))
+			return -1;
+
+		dbname = port->database_name;
 #endif
-	}
-	else
+	} else
 		ProcessConfigFile(PGC_POSTMASTER);
 
 	/*
@@ -2517,7 +2524,6 @@ PostgresMain(int argc, char *argv[], const char *username)
 	 * 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 */
@@ -2565,10 +2571,12 @@ PostgresMain(int argc, char *argv[], const char *username)
 					 errmsg("invalid command-line arguments for server process"),
 					 errhint("Try \"%s --help\" for more information.", argv[0])));
 		}
-		BaseInit();
-#ifdef EXECBACKEND
+#ifdef EXEC_BACKEND
 		AttachSharedMemoryAndSemaphores();
 #endif
+		XLOGPathInit();
+
+		BaseInit();
 	}
 	else
 	{
@@ -2845,7 +2853,11 @@ PostgresMain(int argc, char *argv[], const char *username)
 		if (got_SIGHUP)
 		{
 			got_SIGHUP = false;
+#ifdef EXEC_BACKEND
+			read_nondefault_variables();
+#else
 			ProcessConfigFile(PGC_SIGHUP);
+#endif
 		}
 
 		/*
@@ -3199,4 +3211,3 @@ ShowUsage(const char *title)
 
 	pfree(str.data);
 }
-
diff --git a/src/include/access/xlogdefs.h b/src/include/access/xlogdefs.h
index 023469c1cc..057236e4ed 100644
--- a/src/include/access/xlogdefs.h
+++ b/src/include/access/xlogdefs.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/access/xlogdefs.h,v 1.10 2003/11/29 22:40:55 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/access/xlogdefs.h,v 1.11 2003/12/20 17:31:21 momjian Exp $
  */
 #ifndef XLOG_DEFS_H
 #define XLOG_DEFS_H
@@ -33,6 +33,13 @@ typedef struct XLogRecPtr
 	uint32		xrecoff;		/* byte offset of location in log file */
 } XLogRecPtr;
 
+typedef struct XLogwrtResult
+{
+	XLogRecPtr	Write;			/* last byte + 1 written out */
+	XLogRecPtr	Flush;			/* last byte + 1 flushed */
+} XLogwrtResult;
+
+
 /*
  * Macros for comparing XLogRecPtrs
  *
diff --git a/src/include/c.h b/src/include/c.h
index f08f56633d..984bf14fca 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -12,7 +12,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/c.h,v 1.157 2003/11/29 22:40:53 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/c.h,v 1.158 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -793,6 +793,13 @@ extern int	fdatasync(int fildes);
 #define HAVE_STRTOULL 1
 #endif
 
+/* EXEC_BACKEND defines */
+#ifdef EXEC_BACKEND
+#define NON_EXEC_STATIC
+#else
+#define NON_EXEC_STATIC static
+#endif
+
 /* /port compatibility functions */
 #include "port.h"
 
diff --git a/src/include/libpq/libpq-be.h b/src/include/libpq/libpq-be.h
index a7dc475f57..f011afed86 100644
--- a/src/include/libpq/libpq-be.h
+++ b/src/include/libpq/libpq-be.h
@@ -11,7 +11,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/libpq/libpq-be.h,v 1.38 2003/11/29 22:41:03 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/libpq/libpq-be.h,v 1.39 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -27,6 +27,11 @@
 #endif
 
 
+typedef enum CAC_state
+{
+	CAC_OK, CAC_STARTUP, CAC_SHUTDOWN, CAC_RECOVERY, CAC_TOOMANY
+} CAC_state;
+
 /*
  * This is used by the postmaster in its communication with frontends.	It
  * contains all state information needed during this communication before the
@@ -42,6 +47,7 @@ typedef struct Port
 	ProtocolVersion proto;		/* FE/BE protocol version */
 	SockAddr	laddr;			/* local addr (postmaster) */
 	SockAddr	raddr;			/* remote addr (client) */
+	CAC_state	canAcceptConnections;	/* postmaster connection status */
 
 	/*
 	 * Information that needs to be saved from the startup packet and
diff --git a/src/include/storage/fd.h b/src/include/storage/fd.h
index cb81f36a8a..35a75a3671 100644
--- a/src/include/storage/fd.h
+++ b/src/include/storage/fd.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/fd.h,v 1.40 2003/11/29 22:41:13 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/storage/fd.h,v 1.41 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -77,4 +77,8 @@ extern void RemovePgTempFiles(void);
 extern int	pg_fsync(int fd);
 extern int	pg_fdatasync(int fd);
 
+/* Filename components for OpenTemporaryFile */
+#define PG_TEMP_FILES_DIR "pgsql_tmp"
+#define PG_TEMP_FILE_PREFIX "pgsql_tmp"
+
 #endif   /* FD_H */
diff --git a/src/include/storage/ipc.h b/src/include/storage/ipc.h
index fb59cd0200..3c2765cc48 100644
--- a/src/include/storage/ipc.h
+++ b/src/include/storage/ipc.h
@@ -11,7 +11,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/ipc.h,v 1.63 2003/12/12 18:45:10 petere Exp $
+ * $PostgreSQL: pgsql/src/include/storage/ipc.h,v 1.64 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -32,6 +32,8 @@ extern void on_exit_reset(void);
 extern void CreateSharedMemoryAndSemaphores(bool makePrivate,
 								int maxBackends,
 								int port);
+#ifdef EXEC_BACKEND
 extern void AttachSharedMemoryAndSemaphores(void);
+#endif
 
 #endif   /* IPC_H */
diff --git a/src/include/storage/lock.h b/src/include/storage/lock.h
index a7d66b835e..2d13e9df11 100644
--- a/src/include/storage/lock.h
+++ b/src/include/storage/lock.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/lock.h,v 1.75 2003/12/01 21:59:25 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/storage/lock.h,v 1.76 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -86,8 +86,6 @@ typedef uint16 LOCKMETHODID;
  */
 typedef struct LockMethodData
 {
-	HTAB		   *lockHash;
-	HTAB		   *proclockHash;
 	LOCKMETHODID	lockmethodid;
 	int				numLockModes;
 	LOCKMASK		conflictTab[MAX_LOCKMODES];
diff --git a/src/include/storage/lwlock.h b/src/include/storage/lwlock.h
index db5b3d49bb..34f9c6613c 100644
--- a/src/include/storage/lwlock.h
+++ b/src/include/storage/lwlock.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/lwlock.h,v 1.9 2003/11/29 22:41:13 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/storage/lwlock.h,v 1.10 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -29,7 +29,6 @@ typedef enum LWLockId
 	LockMgrLock,
 	OidGenLock,
 	XidGenLock,
-	ShmemIndexLock,
 	SInvalLock,
 	FreeSpaceLock,
 	MMCacheLock,
diff --git a/src/include/storage/shmem.h b/src/include/storage/shmem.h
index a818f65fe9..648cdf8c3a 100644
--- a/src/include/storage/shmem.h
+++ b/src/include/storage/shmem.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/shmem.h,v 1.40 2003/11/29 22:41:13 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/storage/shmem.h,v 1.41 2003/12/20 17:31:21 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -61,7 +61,7 @@ typedef struct SHM_QUEUE
 } SHM_QUEUE;
 
 /* shmem.c */
-extern void InitShmemAllocation(void *seghdr);
+extern void InitShmemAllocation(void *seghdr, bool init);
 extern void *ShmemAlloc(Size size);
 extern bool ShmemIsValid(unsigned long addr);
 extern void InitShmemIndex(void);