fix decompression with -o writing into a block device #3584
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
decompression features automatic support of sparse files, aka a form of "compression" where entire blocks consists only of zeroes. This only works for some compatible file systems (like ext4), others simply ignore it (like afs). Triggering this feature relies of `fseek()`. But `fseek()` is not compatible with non-seekable devices, such as pipes. Therefore it's disabled for pipes. However, there are other objects which are not compatible with `fseek()`, such as block devices. Changed the logic, so that `fseek()` (and therefore sparse write) is only automatically enabled on regular files. Note that this automatic behavior can always be overridden by explicit commands `--sparse` and `--no-sparse`. fix #3583
Cyan4973
force-pushed
the
fix_o_blockdev
branch
from
6c094cd
to
5bf1359
Compare
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Outdated suggestions cannot be applied.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.
Decompression features automatic support of sparse files,
aka a form of "compression" where entire blocks consists only of zeroes.
This only works for some compatible file systems (like
ext4),others simply ignore it (like
afs).Triggering this feature relies of
fseek().But
fseek()is not compatible with non-seekable devices, such as pipes.Therefore it's disabled for pipes.
However, there are other objects which are not compatible with
fseek(), such as block devices.Changed the logic, so that
fseek()(and therefore sparse write) is only automatically enabled on regular files.Note that this automatic behavior can always be overridden by explicit commands
--sparseand--no-sparse.fix #3583