Fix Efficient access to streambuf buffer #2361
Merged
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
Currently we were always taking the buffer from the moved in string, but would only take it when the buffer could be read or written to. Consequently if that was not the case we would leak the allocated memory. Also simplify the code a bit, we know that the capacity `_Res` will always be nonzero due to the was `_Release_to_buffer` works Also add tests for the error cases
miscco
commented
Nov 27, 2021
| _State |= _From_rvalue; | ||
| if ((_State & _Noread) && (_State & _Constant)) { // Cannot read / write buffer, do nothing | ||
| _Seekhigh = nullptr; | ||
| _Mystate = _State | _From_rvalue; |
There was a problem hiding this comment.
I am slightly unsure whether the _From_rvalue is really applicable here
There was a problem hiding this comment.
Seems reasonable to keep.
StephanTLavavej
approved these changes
Dec 1, 2021
barcharcraz
approved these changes
Dec 11, 2021
| @@ -189,6 +189,7 @@ public: | |||
| _Mystate &= ~_Allocated; | |||
| } | |||
| } | |||
|
|
|||
There was a problem hiding this comment.
This appears to be a stray change, although we do usually seperate the statements following an else block with a single newline
There was a problem hiding this comment.
I'm okay with this small drive-by style improvement.
|
I'm mirroring this to the MSVC-internal repo - please notify me if any further changes are pushed. |
|
Thanks for finding and fixing this memory leak! 🔍 🛠️ 😸 |
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Outdated suggestions cannot be applied.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.
Currently we were always taking the buffer from the moved in string, but would only store it when the buffer could be read or written to.
Consequently if that was not the case we would leak the allocated memory.
Also simplify the code a bit, we know that the capacity
_Reswill always be nonzero due to the way_Release_to_bufferworksAlso add tests for the error cases
@brevzin