From: Patrick Steinhardt <ps@pks.im>
To: git@vger.kernel.org
Cc: Taylor Blau <me@ttaylorr.com>, Toon Claes <toon@iotcl.com>,
Phillip Wood <phillip.wood123@gmail.com>,
Junio C Hamano <gitster@pobox.com>
Subject: [PATCH 0/5] cat-file: introduce NUL-terminated output format
Date: Fri, 2 Jun 2023 15:02:26 +0200 [thread overview]
Message-ID: <cover.1685710884.git.ps@pks.im> (raw)
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Hi,
with Git v2.38.0, we have introduced the `-z` option to git-cat-file(1)
that causes it to read NUL-terminated queries from standard input
instead of the newline-terminated queries. This fixes issues when the
query themselves contains a newline, like it can happen if e.g. we need
to pass a path-scoped revision with embedded newlines.
Unfortunately, this change is causing a new problem. When the object
cannot be looked up, then we print an error message that echoes the
input:
```
$ echo does-not-exist | git cat-file --batch
does-not-exist missing
```
Now if the input itself contains newlines then the output can become
inherently unparsable:
```
$ printf "7ce4f05bae8120d9fa258e854a8669f6ea9cb7b1 blob 10\n1234567890\n\n\commit000" |
git cat-file --batch -z
7ce4f05bae8120d9fa258e854a8669f6ea9cb7b1 blob 10
1234567890
commit missing
```
Ideally, `-z` should have also switched the output to be NUL-terminated.
But it didn't, and we cannot change this issue now without doing a
backwards incompatible change. Instead, this series introduces a new
`-Z` mode that switches both input and output to be NUL-terminated to
fix the issue.
Note that Toon has sent a patch series for this issue to address the
same issue, see the thread starting at [1]. I've collaborated with him
internally at GitLab to arrive at this new patch series which thus
effectively supersedes the patches he has sent. The approach is also
different: while his patches start quoting the output, the approach
chosen by my series only changes the lines to be NUL terminated. This
should make it easier to use for scripted purposes compared to having to
de-quote the input.
I've put all folks that participated in the original thread into Cc.
Patrick
[1]: <20221209150048.2400648-1-toon@iotcl.com>
Patrick Steinhardt (5):
t1006: don't strip timestamps from expected results
t1006: modernize test style to use `test_cmp`
strbuf: provide CRLF-aware helper to read until a specified delimiter
cat-file: simplify reading from standard input
cat-file: Introduce new option to delimit output with NUL characters
Documentation/git-cat-file.txt | 13 +-
builtin/cat-file.c | 85 +++++------
strbuf.c | 11 +-
strbuf.h | 12 ++
t/t1006-cat-file.sh | 249 +++++++++++++++++++++------------
5 files changed, 232 insertions(+), 138 deletions(-)
--
2.40.1
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next reply other threads:[~2023-06-02 13:02 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-02 13:02 Patrick Steinhardt [this message]
2023-06-02 13:02 ` [PATCH 1/5] t1006: don't strip timestamps from expected results Patrick Steinhardt
2023-06-02 13:02 ` [PATCH 2/5] t1006: modernize test style to use `test_cmp` Patrick Steinhardt
2023-06-02 13:02 ` [PATCH 3/5] strbuf: provide CRLF-aware helper to read until a specified delimiter Patrick Steinhardt
2023-06-02 13:02 ` [PATCH 4/5] cat-file: simplify reading from standard input Patrick Steinhardt
2023-06-02 13:02 ` [PATCH 5/5] cat-file: Introduce new option to delimit output with NUL characters Patrick Steinhardt
2023-06-05 15:47 ` Phillip Wood
2023-06-05 23:54 ` Junio C Hamano
2023-06-06 4:52 ` Patrick Steinhardt
2023-06-06 5:22 ` Junio C Hamano
2023-06-06 5:31 ` Patrick Steinhardt
2023-06-12 19:12 ` Junio C Hamano
2023-06-06 5:00 ` Patrick Steinhardt
2023-06-06 1:23 ` Junio C Hamano
2023-06-03 1:44 ` [PATCH 0/5] cat-file: introduce NUL-terminated output format Junio C Hamano
2023-06-06 5:19 ` [PATCH v2 0/5] catfile: " Patrick Steinhardt
2023-06-06 5:19 ` [PATCH v2 1/5] t1006: don't strip timestamps from expected results Patrick Steinhardt
2023-06-06 5:19 ` [PATCH v2 2/5] t1006: modernize test style to use `test_cmp` Patrick Steinhardt
2023-06-06 5:19 ` [PATCH v2 3/5] strbuf: provide CRLF-aware helper to read until a specified delimiter Patrick Steinhardt
2023-06-06 5:19 ` [PATCH v2 4/5] cat-file: simplify reading from standard input Patrick Steinhardt
2023-06-06 5:19 ` [PATCH v2 5/5] cat-file: introduce option to delimit input and output with NUL Patrick Steinhardt
2023-06-12 20:43 ` [PATCH v2 0/5] catfile: introduce NUL-terminated output format Junio C Hamano
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