New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
gadget, osutil: use atomic file copy, adjust tests #9103
Merged
cmatsuoka
merged 4 commits into
snapcore:master
from
bboozzoo:bboozzoo/uc20-mountedfs-atomic-file
Aug 6, 2020
Merged
Changes from 3 commits
Commits
Show all changes
4 commits
Select commit
Hold shift + click to select a range
File filter
Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
There are no files selected for viewing
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
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
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
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
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Outdated suggestions cannot be applied.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.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
It slightly bothers me slightly that "CopyFileAtomic" takes different flags than "CopyFile()". OTOH maybe the perfect should not be the enemy of the good and we can always tweak/fix further as needed.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
The problem is that we cannot really make any use of the flags. CopyFlagSync is meaningless because we always sync, CopyFlagOverwrite is racy unless we try to open the dst file with O_CREAT|O_EXCL next to AtomicFile, lastly CopyFlagPreserveAll cannot be implemented right now without calling
cp
under the hood. In that sense, the semantics are more like AtomicFile, so instead passing CopyFlags, it's taking AtomicWriteFlags.There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
maybe this should be called AtomicCopyFile. Regarding needeing cp, we could use it if needed and cp to a random file name and then AtomicRename that to the final name, it's not our current use case I think though.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
The other possible naming would be AtomicWriteFileCopy, in that case though src and dst would have to be swapped I think
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
I like AtomicWriteFileCopy() and we can always consolidate into CopyFile() with the Atomic flag later, maybe a XXX: should we merge into CopyFIle with new AtomicCopyFile or similar.