Fix init_irels to close the pg_internal.init file before returning.

This saves one open file descriptor per backend, and avoids an
annoying NOTICE on Cygwin (which has trouble deleting open files).
Bug appears to date back to original coding of init_irels, circa 1992.

src/backend/utils/cache/relcache.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.150 2002/01/15 22:33:20 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.151 2002/01/16 17:34:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2659,33 +2659,22 @@ init_irels(void)
 		return;
 	}
 
-	FileSeek(fd, 0L, SEEK_SET);
-
 	for (relno = 0; relno < Num_indices_bootstrap; relno++)
 	{
 		/* first read the relation descriptor length */
 		if ((nread = FileRead(fd, (char *) &len, sizeof(len))) != sizeof(len))
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		/* safety check for incompatible relcache layout */
 		if (len != sizeof(RelationData))
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		ird = irel[relno] = (Relation) palloc(len);
 		MemSet(ird, 0, len);
 
 		/* then, read the Relation structure */
 		if ((nread = FileRead(fd, (char *) ird, len)) != len)
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		/* reset transient fields */
 		ird->rd_targblock = InvalidBlockNumber;
@@ -2696,33 +2685,21 @@ init_irels(void)
 
 		/* next, read the access method tuple form */
 		if ((nread = FileRead(fd, (char *) &len, sizeof(len))) != sizeof(len))
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		am = (Form_pg_am) palloc(len);
 		if ((nread = FileRead(fd, (char *) am, len)) != len)
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		ird->rd_am = am;
 
 		/* next read the relation tuple form */
 		if ((nread = FileRead(fd, (char *) &len, sizeof(len))) != sizeof(len))
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		relform = (Form_pg_class) palloc(len);
 		if ((nread = FileRead(fd, (char *) relform, len)) != len)
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		ird->rd_rel = relform;
 
@@ -2734,18 +2711,12 @@ init_irels(void)
 		for (i = 0; i < relform->relnatts; i++)
 		{
 			if ((nread = FileRead(fd, (char *) &len, sizeof(len))) != sizeof(len))
-			{
-				write_irels();
-				return;
-			}
+				goto read_failed;
 
 			ird->rd_att->attrs[i] = (Form_pg_attribute) palloc(len);
 
 			if ((nread = FileRead(fd, (char *) ird->rd_att->attrs[i], len)) != len)
-			{
-				write_irels();
-				return;
-			}
+				goto read_failed;
 		}
 
 		/*
@@ -2761,17 +2732,11 @@ init_irels(void)
 
 		/* next, read the index strategy map */
 		if ((nread = FileRead(fd, (char *) &len, sizeof(len))) != sizeof(len))
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		strat = (IndexStrategy) MemoryContextAlloc(indexcxt, len);
 		if ((nread = FileRead(fd, (char *) strat, len)) != len)
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
 
 		/* have to invalidate any FmgrInfo data in the strategy maps */
 		nstrategies = am->amstrategies * relform->relnatts;
@@ -2782,17 +2747,11 @@ init_irels(void)
 
 		/* finally, read the vector of support procedures */
 		if ((nread = FileRead(fd, (char *) &len, sizeof(len))) != sizeof(len))
-		{
-			write_irels();
-			return;
-		}
-
+			goto read_failed;
 		support = (RegProcedure *) MemoryContextAlloc(indexcxt, len);
 		if ((nread = FileRead(fd, (char *) support, len)) != len)
-		{
-			write_irels();
-			return;
-		}
+			goto read_failed;
+
 		ird->rd_support = support;
 
 		nsupport = relform->relnatts * am->amsupport;
@@ -2804,7 +2763,16 @@ init_irels(void)
 
 		RelationCacheInsert(ird);
 	}
+
+	/* successfully read the init file */
+	FileClose(fd);
 	criticalRelcachesBuilt = true;
+	return;
+
+	/* init file is broken, so do it the hard way */
+read_failed:
+	FileClose(fd);
+	write_irels();
 }
 
 static void
@@ -2976,6 +2944,10 @@ write_irels(void)
 	/*
 	 * And rename the temp file to its final name, deleting any
 	 * previously-existing init file.
+	 *
+	 * Note: a failure here is possible under Cygwin, if some other
+	 * backend is holding open an unlinked-but-not-yet-gone init file.
+	 * So treat this as a noncritical failure.
 	 */
 	if (rename(tempfilename, finalfilename) < 0)
 	{