Improve error message on snapshot import in snapmgr.c

michaelpq · michaelpq · commit be3dfd3dff03 · 2023-09-14T10:30:23.000+09:00
When a snapshot file fails to be read in ImportSnapshot(), it would issue an ERROR as "invalid snapshot identifier" when opening a stream for it in read-only mode. This error message is reworded to be the same as all the other messages used in this case on failure, which is useful when debugging this area. Thinko introduced by bb446b6 where snapshot imports have been added. A backpatch down to 11 is done as this can improve any work related to snapshot imports in older branches. Author: Bharath Rupireddy Reviewed-by: Daniel Gustafsson Discussion: https://postgr.es/m/CALj2ACWmr=3KdxDkm8h7Zn1XxBoF6hdzq8WQyMn2y1OL5RYFrg@mail.gmail.com Backpatch-through: 11
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c
@@ -1445,8 +1445,9 @@ ImportSnapshot(const char *idstr)
 	f = AllocateFile(path, PG_BINARY_R);
 	if (!f)
 		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid snapshot identifier: \"%s\"", idstr)));
+				(errcode_for_file_access(),
+				 errmsg("could not open file \"%s\" for reading: %m",
+						path)));
 
 	/* get the size of the file so that we know how much memory we need */
 	if (fstat(fileno(f), &stat_buf))
