WT-2737 page scrubbing: more fixes (#2901)

Rework 8bfe54b: we have to swap the page-header before calculating the
checksum and I don't want to leave the caller's data changed in the case
of an error. I also don't want to rework all the error handling in the
__wt_block_write_off() function, so wrap the block-write functionality
in a new function that only handles page-header swapping.

1 files changed, 31 insertions, 13 deletions

diff --git a/src/block/block_write.c b/src/block/block_write.c
index 8a77641e1f3..30d06e6259a 100644
--- a/src/block/block_write.c
+++ b/src/block/block_write.c
@@ -228,12 +228,12 @@ __wt_block_write(WT_SESSION_IMPL *session, WT_BLOCK *block, WT_ITEM *buf,
 }
 
 /*
- * __wt_block_write_off --
+ * __block_write_off --
  *	Write a buffer into a block, returning the block's offset, size and
  * checksum.
  */
-int
-__wt_block_write_off(WT_SESSION_IMPL *session, WT_BLOCK *block,
+static int
+__block_write_off(WT_SESSION_IMPL *session, WT_BLOCK *block,
     WT_ITEM *buf, wt_off_t *offsetp, uint32_t *sizep, uint32_t *cksump,
     bool data_cksum, bool checkpoint_io, bool caller_locked)
 {
@@ -339,16 +339,9 @@ __wt_block_write_off(WT_SESSION_IMPL *session, WT_BLOCK *block,
 		__wt_spin_unlock(session, &block->live_lock);
 	WT_RET(ret);
 
-	/*
-	 * Ensure the page header is in little endian order; this doesn't belong
-	 * here, but it's the best place to catch all callers. After the write,
-	 * swap values back to native order so callers never see anything other
-	 * than their original content.
-	 */
-	__wt_page_header_byteswap(buf->mem);
-	ret = __wt_write(session, fh, offset, align_size, buf->mem);
-	__wt_page_header_byteswap(buf->mem);
-	if (ret != 0) {
+	/* Write the block. */
+	if ((ret =
+	    __wt_write(session, fh, offset, align_size, buf->mem)) != 0) {
 		if (!caller_locked)
 			__wt_spin_lock(session, &block->live_lock);
 		WT_TRET(__wt_block_off_free(
@@ -395,3 +388,28 @@ __wt_block_write_off(WT_SESSION_IMPL *session, WT_BLOCK *block,
 
 	return (0);
 }
+
+/*
+ * __wt_block_write_off --
+ *	Write a buffer into a block, returning the block's offset, size and
+ * checksum.
+ */
+int
+__wt_block_write_off(WT_SESSION_IMPL *session, WT_BLOCK *block,
+    WT_ITEM *buf, wt_off_t *offsetp, uint32_t *sizep, uint32_t *cksump,
+    bool data_cksum, bool checkpoint_io, bool caller_locked)
+{
+	WT_DECL_RET;
+
+	/*
+	 * Ensure the page header is in little endian order; this doesn't belong
+	 * here, but it's the best place to catch all callers. After the write,
+	 * swap values back to native order so callers never see anything other
+	 * than their original content.
+	 */
+	__wt_page_header_byteswap(buf->mem);
+	ret = __block_write_off(session, block, buf,
+	    offsetp, sizep, cksump, data_cksum, checkpoint_io, caller_locked);
+	__wt_page_header_byteswap(buf->mem);
+	return (ret);
+}