Code review for EXEC_BACKEND changes. Reduce the number of #ifdefs by

about a third, make it work on non-Windows platforms again.  (But perhaps
I broke the WIN32 code, since I have no way to test that.)  Fold all the
paths that fork postmaster child processes to go through the single
routine SubPostmasterMain, which takes care of resurrecting the state that
would normally be inherited from the postmaster (including GUC variables).
Clean up some places where there's no particularly good reason for the
EXEC and non-EXEC cases to work differently.  Take care of one or two
FIXMEs that remained in the code.

src/backend/access/transam/slru.c

@@ -6,7 +6,7 @@
  * 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/slru.c,v 1.13 2004/02/23 23:03:10 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/slru.c,v 1.14 2004/05/28 05:12:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -164,10 +164,9 @@ static bool SlruScanDirectory(SlruCtl ctl, int cutoffPage, bool doDeletions);
 int
 SimpleLruShmemSize(void)
 {
-	return MAXALIGN(sizeof(SlruSharedData)) + BLCKSZ * NUM_CLOG_BUFFERS
-#ifdef EXEC_BACKEND
+	return MAXALIGN(sizeof(SlruSharedData))
+		+ BLCKSZ * NUM_CLOG_BUFFERS
 		+ MAXALIGN(sizeof(SlruLockData))
-#endif
 		;
 }
 
@@ -181,21 +180,8 @@ SimpleLruInit(SlruCtl ctl, const char *name, const char *subdir)
 
 	ptr = ShmemInitStruct(name, SimpleLruShmemSize(), &found);
 	shared = (SlruShared) ptr;
-
-#ifdef EXEC_BACKEND
-	/*
-	 * Locks are in shared memory
-	 */
 	locks = (SlruLock) (ptr + MAXALIGN(sizeof(SlruSharedData)) +
 						BLCKSZ * NUM_CLOG_BUFFERS);
-#else
-	/*
-	 * Locks are in private memory
-	 */
-	Assert(!IsUnderPostmaster);
-	locks = malloc(sizeof(SlruLockData));
-	Assert(locks);
-#endif
 
 	if (!IsUnderPostmaster)
 	{
@@ -225,6 +211,7 @@ SimpleLruInit(SlruCtl ctl, const char *name, const char *subdir)
 	else
 		Assert(found);
 
+	/* Initialize the unshared control struct */
 	ctl->locks = locks;
 	ctl->shared = shared;