[gentoo-portage-dev] [PATCH] egencache --write-timestamp: use write_atomic (bug 577126)

[gentoo-portage-dev] [PATCH] egencache --write-timestamp: use write_atomic (bug 577126)

[Zac Medico]

Use write_atomic in order to create a new inode. This leads to
copy-on-write behavior with hardlinks, which is useful if someone
wants to use hardlinks to create copy-on-write repository
snapshots on a filesystem such as ext4 (no need for btrfs or zfs).

X-Gentoo-bug: 577126
X-Gentoo-bug-url: https://bugs.gentoo.org/show_bug.cgi?id=577126
---
 bin/egencache | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/bin/egencache b/bin/egencache
index 7e3387e..0123d57 100755
--- a/bin/egencache
+++ b/bin/egencache
@@ -1165,9 +1165,9 @@ def egencache_main(args):
 	if options.write_timestamp:
 		timestamp_path = os.path.join(repo_path, 'metadata', 'timestamp.chk')
 		try:
-			with open(timestamp_path, 'w') as f:
-				f.write(time.strftime('%s\n' % TIMESTAMP_FORMAT, time.gmtime()))
-		except IOError:
+			portage.util.write_atomic(timestamp_path,
+				time.strftime('%s\n' % TIMESTAMP_FORMAT, time.gmtime()))
+		except (EnvironmentError, portage.exception.PortageException):
 			ret.append(os.EX_IOERR)
 		else:
 			ret.append(os.EX_OK)
-- 
2.7.2

Re: [gentoo-portage-dev] [PATCH] egencache --write-timestamp: use write_atomic (bug 577126)

[Brian Dolbec]

On Sat, 12 Mar 2016 00:29:49 -0800
Zac Medico <zmedico@gentoo.org> wrote:

> Use write_atomic in order to create a new inode. This leads to
> copy-on-write behavior with hardlinks, which is useful if someone
> wants to use hardlinks to create copy-on-write repository
> snapshots on a filesystem such as ext4 (no need for btrfs or zfs).
> 
> X-Gentoo-bug: 577126
> X-Gentoo-bug-url: https://bugs.gentoo.org/show_bug.cgi?id=577126
> ---
>  bin/egencache | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/bin/egencache b/bin/egencache
> index 7e3387e..0123d57 100755
> --- a/bin/egencache
> +++ b/bin/egencache
> @@ -1165,9 +1165,9 @@ def egencache_main(args):
>  	if options.write_timestamp:
>  		timestamp_path = os.path.join(repo_path, 'metadata',
> 'timestamp.chk') try:
> -			with open(timestamp_path, 'w') as f:
> -				f.write(time.strftime('%s\n' %
> TIMESTAMP_FORMAT, time.gmtime()))
> -		except IOError:
> +			portage.util.write_atomic(timestamp_path,
> +				time.strftime('%s\n' %
> TIMESTAMP_FORMAT, time.gmtime()))
> +		except (EnvironmentError,
> portage.exception.PortageException): ret.append(os.EX_IOERR)
>  		else:
>  			ret.append(os.EX_OK)


looks fine to me.

-- 
Brian Dolbec <dolsen>