diff mbox

support/download: generate reproducible Bazaar archives

Message ID 1451747202-21873-1-git-send-email-yann.morin.1998@free.fr
State Accepted
Commit efe7f684a66b54bf133e6b377b19653a163c89e0
Headers show

Commit Message

Yann E. MORIN Jan. 2, 2016, 3:06 p.m. UTC
Similarly to what has previously been done for the Hg download backend,
instruct bzr to generate the archive on stdout, so that we can generate
reproducible archives.

When instructing bzr to generate the output file by itself, it uses a
temporary file that is then fed to gzip, which in turn stores the
timestamp of that file in the generated archive, whereas when the output
is generated on stdout, there is no timestamp, so the archive is then
reproducible.

Bizarely enough, we can tell 'bazaar' not to generate a bazaar in the
archive. Cool, uh? ;-]

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
---
 support/download/bzr | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Peter Korsgaard Jan. 3, 2016, 8:51 p.m. UTC | #1
>>>>> "Yann" == Yann E MORIN <yann.morin.1998@free.fr> writes:

 > Similarly to what has previously been done for the Hg download backend,
 > instruct bzr to generate the archive on stdout, so that we can generate
 > reproducible archives.

 > When instructing bzr to generate the output file by itself, it uses a
 > temporary file that is then fed to gzip, which in turn stores the
 > timestamp of that file in the generated archive, whereas when the output
 > is generated on stdout, there is no timestamp, so the archive is then
 > reproducible.

 > Bizarely enough, we can tell 'bazaar' not to generate a bazaar in the
 > archive. Cool, uh? ;-]

:P

Committed, thanks.
diff mbox

Patch

diff --git a/support/download/bzr b/support/download/bzr
index cec9ce8..a8a8887 100755
--- a/support/download/bzr
+++ b/support/download/bzr
@@ -32,4 +32,6 @@  _bzr() {
     eval ${BZR} "${@}"
 }
 
-_bzr export ${verbose} --root="'${basename}/'" --format=tgz "'${output}'" "'${repo}'" -r "'${rev}'"
+_bzr export ${verbose} --root="'${basename}/'" --format=tgz \
+    --per-file-timestamps - "'${repo}'" -r "'${rev}'" \
+    >"${output}"