mingw_open_existing: handle directories better #5342
Draft
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
CreateFileW() requires FILE_FLAG_BACKUP_SEMANTICS to create a directory handle [1] and errors out with ERROR_ACCESS_DENIED without this flag. Fall back to accessing Directory handles this way. [1] https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilew#directories This fixes git-for-windows#5068 Signed-off-by: Matthias Aßhauer <[email protected]>
rimrul
commented
Jan 5, 2025
| @@ -810,13 +810,24 @@ static int mingw_open_existing(const wchar_t *filename, int oflags, ...) | |||
| &security_attributes, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL); | |||
| if (handle == INVALID_HANDLE_VALUE) { | |||
| DWORD err = GetLastError(); | |||
| if (err == ERROR_ACCESS_DENIED) { | |||
| DWORD attrs = GetFileAttributesW(filename); | |||
There was a problem hiding this comment.
We could probably also check GetFileAttributesW() before the first CreateFileW() and avoid calling CreateFileW() twice.
There was a problem hiding this comment.
I think the current version is fine because it optimizes for the common case, avoiding the extra GetFileAttributesW() & CreateFileW() calls for the vast majority of calls.
dscho
approved these changes
Jan 7, 2025
| @@ -810,13 +810,24 @@ static int mingw_open_existing(const wchar_t *filename, int oflags, ...) | |||
| &security_attributes, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL); | |||
| if (handle == INVALID_HANDLE_VALUE) { | |||
| DWORD err = GetLastError(); | |||
| if (err == ERROR_ACCESS_DENIED) { | |||
| DWORD attrs = GetFileAttributesW(filename); | |||
There was a problem hiding this comment.
I think the current version is fine because it optimizes for the common case, avoiding the extra GetFileAttributesW() & CreateFileW() calls for the vast majority of calls.
|
It looks like t5616 has a newly-introduced flake now:
I've restarted the job. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
CreateFileW()requiresFILE_FLAG_BACKUP_SEMANTICSto create a directory handle and errors out withERROR_ACCESS_DENIEDwithout this flag. Fall back to accessing Directory handles this way.This fixes #5068