Re: WriteBuffer return value

On Wed, 12 Jun 2002 10:19:17 -0400, Tom Lane  wrote:
>I'd vote for changing WriteBuffer to
>return void, and have it elog() on bad argument.

Whatever you want ...
BTW, to avoid rejected hunks this patch should be applied after the
EliminateUnused patch I posted 2002-06-10.

diff -ur ../orig/src/backend/commands/sequence.c src/backend/commands/sequence.c
--- ../orig/src/backend/commands/sequence.c	2002-06-10 15:40:46.000000000 +0200
+++ src/backend/commands/sequence.c	2002-06-13 09:32:25.000000000 +0200
@@ -468,8 +468,7 @@
 
 	LockBuffer(buf, BUFFER_LOCK_UNLOCK);
 
-	if (WriteBuffer(buf) == STATUS_ERROR)
-		elog(ERROR, "%s.nextval: WriteBuffer failed", sequence->relname);
+	WriteBuffer(buf);
 
 	relation_close(seqrel, NoLock);
 
@@ -581,8 +580,7 @@
 
 	LockBuffer(buf, BUFFER_LOCK_UNLOCK);
 
-	if (WriteBuffer(buf) == STATUS_ERROR)
-		elog(ERROR, "%s.setval: WriteBuffer failed", sequence->relname);
+	WriteBuffer(buf);
 
 	relation_close(seqrel, NoLock);
 }
diff -ur ../orig/src/backend/storage/buffer/bufmgr.c src/backend/storage/buffer/bufmgr.c
--- ../orig/src/backend/storage/buffer/bufmgr.c	2002-06-10 15:00:57.000000000 +0200
+++ src/backend/storage/buffer/bufmgr.c	2002-06-13 09:32:40.000000000 +0200
@@ -87,6 +87,7 @@
 static int	BufferReplace(BufferDesc *bufHdr);
 void		PrintBufferDescs(void);
 
+static void write_buffer(Buffer buffer, bool unpin);
 
 /*
  * ReadBuffer -- returns a buffer containing the requested
@@ -558,29 +559,22 @@
 }
 
 /*
- * WriteBuffer
- *
- *		Marks buffer contents as dirty (actual write happens later).
- *
- * Assume that buffer is pinned.  Assume that reln is
- *		valid.
- *
- * Side Effects:
- *		Pin count is decremented.
+ * write_buffer -- common functionality for
+ *                 WriteBuffer and WriteNoReleaseBuffer
  */
-
-#undef WriteBuffer
-
-int
-WriteBuffer(Buffer buffer)
+static void
+write_buffer(Buffer buffer, bool release)
 {
 	BufferDesc *bufHdr;
 
 	if (BufferIsLocal(buffer))
-		return WriteLocalBuffer(buffer, TRUE);
+	{
+		WriteLocalBuffer(buffer, release);
+		return;
+	}
 
 	if (BAD_BUFFER_ID(buffer))
-		return FALSE;
+		elog(ERROR, "write_buffer: bad buffer %d", buffer);
 
 	bufHdr = &BufferDescriptors[buffer - 1];
 
@@ -589,37 +583,39 @@
 
 	bufHdr->flags |= (BM_DIRTY | BM_JUST_DIRTIED);
 
-	UnpinBuffer(bufHdr);
+	if (release)
+		UnpinBuffer(bufHdr);
 	LWLockRelease(BufMgrLock);
+}
 
-	return TRUE;
+/*
+ * WriteBuffer
+ *
+ *		Marks buffer contents as dirty (actual write happens later).
+ *
+ * Assume that buffer is pinned.  Assume that reln is
+ *		valid.
+ *
+ * Side Effects:
+ *		Pin count is decremented.
+ */
+
+#undef WriteBuffer
+
+void
+WriteBuffer(Buffer buffer)
+{
+	write_buffer(buffer, true);
 }
 
 /*
  * WriteNoReleaseBuffer -- like WriteBuffer, but do not unpin the buffer
  *						   when the operation is complete.
  */
-int
+void
 WriteNoReleaseBuffer(Buffer buffer)
 {
-	BufferDesc *bufHdr;
-
-	if (BufferIsLocal(buffer))
-		return WriteLocalBuffer(buffer, FALSE);
-
-	if (BAD_BUFFER_ID(buffer))
-		return STATUS_ERROR;
-
-	bufHdr = &BufferDescriptors[buffer - 1];
-
-	LWLockAcquire(BufMgrLock, LW_EXCLUSIVE);
-	Assert(bufHdr->refcount > 0);
-
-	bufHdr->flags |= (BM_DIRTY | BM_JUST_DIRTIED);
-
-	LWLockRelease(BufMgrLock);
-
-	return STATUS_OK;
+	write_buffer(buffer, false);
 }
 
 
diff -ur ../orig/src/backend/storage/buffer/localbuf.c src/backend/storage/buffer/localbuf.c
--- ../orig/src/backend/storage/buffer/localbuf.c	2002-05-03 19:42:11.000000000 +0200
+++ src/backend/storage/buffer/localbuf.c	2002-06-13 09:23:56.000000000 +0200
@@ -155,7 +155,7 @@
  * WriteLocalBuffer -
  *	  writes out a local buffer
  */
-int
+void
 WriteLocalBuffer(Buffer buffer, bool release)
 {
 	int			bufid;
@@ -174,8 +174,6 @@
 		Assert(LocalRefCount[bufid] > 0);
 		LocalRefCount[bufid]--;
 	}
-
-	return true;
 }
 
 /*
diff -ur ../orig/src/include/storage/buf_internals.h src/include/storage/buf_internals.h
--- ../orig/src/include/storage/buf_internals.h	2002-06-10 15:03:44.000000000 +0200
+++ src/include/storage/buf_internals.h	2002-06-13 09:23:26.000000000 +0200
@@ -176,7 +176,7 @@
 
 extern BufferDesc *LocalBufferAlloc(Relation reln, BlockNumber blockNum,
 				 bool *foundPtr);
-extern int	WriteLocalBuffer(Buffer buffer, bool release);
+extern void	WriteLocalBuffer(Buffer buffer, bool release);
 extern int	FlushLocalBuffer(Buffer buffer, bool sync, bool release);
 extern void LocalBufferSync(void);
 extern void ResetLocalBufferPool(void);
diff -ur ../orig/src/include/storage/bufmgr.h src/include/storage/bufmgr.h
--- ../orig/src/include/storage/bufmgr.h	2002-04-16 01:47:12.000000000 +0200
+++ src/include/storage/bufmgr.h	2002-06-13 09:22:59.000000000 +0200
@@ -148,8 +148,8 @@
  */
 extern Buffer ReadBuffer(Relation reln, BlockNumber blockNum);
 extern int	ReleaseBuffer(Buffer buffer);
-extern int	WriteBuffer(Buffer buffer);
-extern int	WriteNoReleaseBuffer(Buffer buffer);
+extern void	WriteBuffer(Buffer buffer);
+extern void	WriteNoReleaseBuffer(Buffer buffer);
 extern Buffer ReleaseAndReadBuffer(Buffer buffer, Relation relation,
 					 BlockNumber blockNum);
 extern int	FlushBuffer(Buffer buffer, bool sync, bool release);