mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2025-03-07 19:47:50 +08:00
Code Issues Packages Projects Releases Wiki Activity

Don't trust CreateFileMapping() to clear the error code on success.

Browse Source 
We must test GetLastError() even when CreateFileMapping() returns a
non-null handle.  If that value were left over from some previous system
call, we might be fooled into thinking the segment already existed.
Experimentation on Windows 7 suggests that CreateFileMapping() clears
the error code on success, but it is not documented to do so, so let's
not rely on that happening in all Windows releases.

Amit Kapila

Discussion: <20811.1474390987@sss.pgh.pa.us>
This commit is contained in:
Tom Lane 2016-09-23 10:09:52 -04:00
parent 49a91b88e6
commit 8e6b4ee21f
1 changed files with 3 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
src/backend/storage/ipc/dsm_impl.c
View File

@ -681,6 +681,9 @@ dsm_impl_windows(dsm_op op, dsm_handle handle, Size request_size,
#endif
size_low = (DWORD) request_size;
/* CreateFileMapping might not clear the error code on success */
SetLastError(0);
hmap = CreateFileMapping(INVALID_HANDLE_VALUE, /* Use the pagefile */
NULL, /* Default security attrs */
PAGE_READWRITE, /* Memory is read/write */