Jeff King [Tue, 8 Dec 2020 22:03:33 +0000 (17:03 -0500)]
rev-list: die when --test-bitmap detects a mismatch
You can use "git rev-list --test-bitmap HEAD" to check that bitmaps
produce the same answer we'd get from a regular traversal. But if we
detect an error, we only print "mismatch", and still exit with a
successful error code.
That makes the uses of --test-bitmap in the test suite (e.g., in t5310)
mostly pointless: even if we saw an error, the tests wouldn't notice.
Let's instead call die(), which will let these tests work as designed,
and alert us if the bitmaps are bogus.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Tue, 8 Dec 2020 22:03:28 +0000 (17:03 -0500)]
t5310: drop size of truncated ewah bitmap
We truncate the .bitmap file to 512 bytes and expect to run into
problems reading an individual ewah file. But this length is somewhat
arbitrary, and just happened to work when the test was added in 9d2e330b17 (ewah_read_mmap: bounds-check mmap reads, 2018-06-14).
An upcoming commit will change the size of the history we create in the
test repo, which will cause this test to fail. We can future-proof it a
bit more by reducing the size of the truncated bitmap file.
Signed-off-by: Jeff King <peff@peff.net> Helped-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Tue, 8 Dec 2020 22:03:24 +0000 (17:03 -0500)]
pack-bitmap: bounds-check size of cache extension
A .bitmap file may have a "name hash cache" extension, which puts a
sequence of uint32_t values (one per object) at the end of the file.
When we see a flag indicating this extension, we blindly subtract the
appropriate number of bytes from our available length. However, if the
.bitmap file is too short, we'll underflow our length variable and wrap
around, thinking we have a very large length. This can lead to reading
out-of-bounds bytes while loading individual ewah bitmaps.
We can fix this by checking the number of available bytes when we parse
the header. The existing "truncated bitmap" test is now split into two
tests: one where we don't have this extension at all (and hence actually
do try to read a truncated ewah bitmap) and one where we realize
up-front that we can't even fit in the cache structure. We'll check
stderr in each case to make sure we hit the error we're expecting.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Tue, 8 Dec 2020 22:03:19 +0000 (17:03 -0500)]
pack-bitmap: fix header size check
When we parse a .bitmap header, we first check that we have enough bytes
to make a valid header. We do that based on sizeof(struct
bitmap_disk_header). However, as of 0f4d6cada8 (pack-bitmap: make bitmap
header handling hash agnostic, 2019-02-19), that struct oversizes its
checksum member to GIT_MAX_RAWSZ. That means we need to adjust for the
difference between that constant and the size of the actual hash we're
using. That commit adjusted the code which moves our pointer forward,
but forgot to update the size check.
This meant we were overly strict about the header size (requiring room
for a 32-byte worst-case hash, when sha1 is only 20 bytes). But in
practice it didn't matter because bitmap files tend to have at least 12
bytes of actual data anyway, so it was unlikely for a valid file to be
caught by this.
Let's fix it by pulling the header size into a separate variable and
using it in both spots. That fixes the bug and simplifies the code to make
it harder to have a mismatch like this in the future. It will also come
in handy in the next patch for more bounds checking.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
'ewah/ewah_bitmap.c:buffer_grow()' is responsible for growing the buffer
used to store the bits of an EWAH bitmap. It is essentially doing the
same task as the 'ALLOC_GROW()' macro, so use that instead.
This simplifies the callers of 'buffer_grow()', who no longer have to
ask for a specific size, but rather specify how much of the buffer they
need. They also no longer need to guard 'buffer_grow()' behind an if
statement, since 'ALLOC_GROW()' (and, by extension, 'buffer_grow()') is
a noop if the buffer is already large enough.
But, the most significant change is that this fixes a bug when calling
buffer_grow() with both 'alloc_size' and 'new_size' set to 1. In this
case, truncating integer math will leave the new size set to 1, causing
the buffer to never grow.
Instead, let alloc_nr() handle this, which asks for '(new_size + 16) * 3
/ 2' instead of 'new_size * 3 / 2'.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Wed, 11 Nov 2020 21:18:39 +0000 (13:18 -0800)]
Merge branch 'jc/sequencer-stopped-sha-simplify'
Recently the format of an internal state file "rebase -i" uses has
been tightened up for consistency, which would hurt those who start
"rebase -i" with old git and then continue with new git. Loosen
the reader side a bit (which we may want to tighten again in a year
or so).
Junio C Hamano [Wed, 11 Nov 2020 21:18:38 +0000 (13:18 -0800)]
Merge branch 'js/test-whitespace-fixes'
Test code clean-up.
* js/test-whitespace-fixes:
t9603: use tabs for indentation
t5570: remove trailing padding
t5400,t5402: consistently indent with tabs, not with spaces
t3427: adjust stale comment
t3406: indent with tabs, not spaces
t1004: insert missing "branch" in a message
Prepare a test script to transition of the default branch name to
'main'.
* js/default-branch-name-adjust-t5411:
t5411: finish preparing for `main` being the default branch name
t5411: adjust the remaining support files for init.defaultBranch=main
t5411: start adjusting the support files for init.defaultBranch=main
t5411: start using the default branch name "main"
Junio C Hamano [Mon, 9 Nov 2020 22:06:26 +0000 (14:06 -0800)]
Merge branch 'pb/ref-filter-with-crlf'
A commit and tag object may have CR at the end of each and
every line (you can create such an object with hash-object or
using --cleanup=verbatim to decline the default clean-up
action), but it would make it impossible to have a blank line
to separate the title from the body of the message. Be lenient
and accept a line with lone CR on it as a blank line, too.
* pb/ref-filter-with-crlf:
log, show: add tests for messages containing CRLF
ref-filter: handle CRLF at end-of-line more gracefully
Junio C Hamano [Mon, 9 Nov 2020 22:06:25 +0000 (14:06 -0800)]
Merge branch 'nk/diff-files-vs-fsmonitor'
"git diff" and other commands that share the same machinery to
compare with working tree files have been taught to take advantage
of the fsmonitor data when available.
* nk/diff-files-vs-fsmonitor:
p7519-fsmonitor: add a git add benchmark
p7519-fsmonitor: refactor to avoid code duplication
perf lint: add make test-lint to perf tests
t/perf: add fsmonitor perf test for git diff
t/perf/p7519-fsmonitor.sh: warm cache on first git status
t/perf/README: elaborate on output format
fsmonitor: use fsmonitor data in `git diff`
Junio C Hamano [Mon, 9 Nov 2020 22:06:25 +0000 (14:06 -0800)]
Merge branch 'en/dir-rename-tests'
More preliminary tests have been added to document desired outcome
of various "directory rename" situations.
* en/dir-rename-tests:
t6423: more involved rules for renaming directories into each other
t6423: update directory rename detection tests with new rule
t6423: more involved directory rename test
directory-rename-detection.txt: update references to regression tests
This patch will let the new `check-whitespace` GitHub workflow be happy
with the upcoming patch series that wants to search-and-replace `master`
with `main` in t9603 and some other test scripts.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Two blocks in t5570 want to align the closing double quotes, padding
with spaces if needed. Since the maximum length of those lines is
defined by the branch name `master`, the upcoming rename to `main` would
unalign the quotes.
But then, it is unclear how those aligned closing quotes should help
readability anyway, so let's just remove that padding altogether.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5400,t5402: consistently indent with tabs, not with spaces
This patch actually prepares for the upcoming patches to replace
`master` with `main` in these tests: we do not want those changes to be
flagged by the new `check-whitespace` GitHub workflow (even if those
changes do not introduce the whitespace issues, they touch lines
affected by those issues without fixing them).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In b6211b89eb3 (tests: avoid variations of the `master` branch name,
2020-09-26), the `master[123]` branch names were renamed to
`topic_[123]`. A non-literal mention of the corresponding files was
missed in that commit.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The message in question reads awkward with the name "master", but will
be even more confusing once that is renamed to "main". Let's adjust it
in advance of said rename.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
ci: avoid using the deprecated `set-env` construct
The `set-env` construct was deprecated as of the announcement in
https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/
Let's use the recommended alternative instead.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
tests: consolidate the `file_size` function into `test-lib-functions.sh`
In 8de7eeb54b6 (compression: unify pack.compression configuration
parsing, 2016-11-15), we introduced identical copies of the `file_size`
helper into three test scripts, with the plan to eventually consolidate
them into a single copy.
Let's do that, and adjust the function name to adhere to the `test_*`
naming convention.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Reviewed-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Wed, 4 Nov 2020 22:01:37 +0000 (14:01 -0800)]
doc: clarify that --abbrev=<n> is about the minimum length
Early text written in 2006 explains the "--abbrev=<n>" option to
"show only a partial prefix", without saying that the length of the
partial prefix is not necessarily the number given to the option to
ensure that the output names the object uniquely.
Update documentation for the diff family of commands, "blame",
"branch --verbose", "ls-files" and "ls-tree" to stress that the
short prefix must uniquely refer to an object, and <n> is merely
the mininum number of hexdigits used in the prefix.
Helped-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 32c83afc2c69 (ci: github action - add check for whitespace errors,
2020-09-22), we introduced a GitHub workflow that automatically checks
Pull Requests for whitespace problems.
However, when affected lines contain one or more double quote
characters, this workflow failed to attach the informative comment
because the Javascript snippet incorrectly interpreted these quotes
instead of using the `git log` output as-is.
Let's fix that.
While at it, let's `await` the result of the `createComment()` function.
Finally, we enclose the log in the comment with ```...``` to avoid
having the diff marker be misinterpreted as an enumeration bullet.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In c57b3367bed (worktree: teach `list` to annotate locked worktree,
2020-10-11), we introduced a test case that wanted to talk about
"worktrees" but talked about "worktress" instead. Let's fix that.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adjust tests so that they won't scream when the default initial
branch name is changed to 'main'.
* js/default-branch-name-part-4-minus-1:
t1400: prepare for `main` being default branch name
tests: prepare aligned mentions of the default branch name
t9902: prepare a test for the upcoming default branch name
t3200: prepare for `main` being shorter than `master`
t5703: adjust a test case for the upcoming default branch name
t6200: adjust suppression pattern to also match "main"
tests: start moving to a different default main branch name
t9801: use `--` in preparation for default branch rename
fmt-merge-msg: also suppress "into main" by default
Junio C Hamano [Mon, 2 Nov 2020 21:17:43 +0000 (13:17 -0800)]
Merge branch 'jt/apply-reverse-twice'
"git apply -R" did not handle patches that touch the same path
twice correctly, which has been corrected. This is most relevant
in a patch that changes a path from a regular file to a symbolic
link (and vice versa).
* jt/apply-reverse-twice:
apply: when -R, also reverse list of sections
Junio C Hamano [Mon, 2 Nov 2020 21:17:43 +0000 (13:17 -0800)]
Merge branch 'sc/sequencer-gpg-octopus'
"git rebase --rebase-merges" did not correctly pass --gpg-sign
command line option to underlying "git merge" when replaying a merge
using non-default merge strategy or when replaying an octopus merge
(because replaying a two-head merge with the default strategy was
done in a separate codepath, the problem did not trigger for most
users), which has been corrected.
* sc/sequencer-gpg-octopus:
t3435: add tests for rebase -r GPG signing
sequencer: pass explicit --no-gpg-sign to merge
sequencer: fix gpg option passed to merge subcommand
Junio C Hamano [Mon, 2 Nov 2020 21:17:42 +0000 (13:17 -0800)]
Merge branch 'en/test-selector'
Our test scripts can be told to run only individual pieces while
skipping others with the "--run=..." option; they were taught to
take a substring of test title, in addition to numbers, to name the
test pieces to run.
* en/test-selector:
test-lib: reduce verbosity of skipped tests
t6006, t6012: adjust tests to use 'setup' instead of synonyms
test-lib: allow selecting tests by substring/glob with --run
Junio C Hamano [Mon, 2 Nov 2020 21:17:39 +0000 (13:17 -0800)]
Merge branch 'bk/sob-dco'
Document that the meaning of a Signed-off-by trailer can vary from
project to project in the end-user documentation, and clarify what
it means to this project.
* bk/sob-dco:
Documentation: stylistically normalize references to Signed-off-by:
SubmittingPatches: clarify DCO is our --signoff rule
Documentation: clarify and expand description of --signoff
doc: preparatory clean-up of description on the sign-off option
Junio C Hamano [Mon, 2 Nov 2020 21:17:39 +0000 (13:17 -0800)]
Merge branch 'ds/commit-graph-merging-fix'
When "git commit-graph" detects the same commit recorded more than
once while it is merging the layers, it used to die. The code now
ignores all but one of them and continues.
* ds/commit-graph-merging-fix:
commit-graph: don't write commit-graph when disabled
commit-graph: ignore duplicates when merging layers
Junio C Hamano [Mon, 2 Nov 2020 21:17:38 +0000 (13:17 -0800)]
Merge branch 'es/test-cmp-typocatcher'
A test helper "test_cmp A B" was taught to diagnose missing files A
or B as a bug in test, but some tests legitimately wanted to notice
a failure to even create file B as an error, in addition to leaving
the expected result in it, and were misdiagnosed as a bug. This
has been corrected.
Junio C Hamano [Mon, 2 Nov 2020 21:17:37 +0000 (13:17 -0800)]
Merge branch 'js/avoid-split-sideband-message'
The side-band status report can be sent at the same time as the
primary payload multiplexed, but the demultiplexer on the receiving
end incorrectly split a single status report into two, which has
been corrected.
* js/avoid-split-sideband-message:
test-pkt-line: drop colon from sideband identity
sideband: report unhandled incomplete sideband messages as bugs
sideband: avoid reporting incomplete sideband messages
Sibo Dong [Sat, 31 Oct 2020 22:09:46 +0000 (22:09 +0000)]
git-prompt.sh: localize `option` in __git_ps1_show_upstream
The variable 'option' is used in __git_ps1_show_upstream()
without being localized.
This clobbers the variable the user may be using for other
purposes, which is bad. Luckily, $option is not used to carry
information around in the script as a global variable. The use
of it in this script has very limited scope (namely, only inside
this function), so just declare that it is "local".
Signed-off-by: Sibo Dong <sibo.dong@outlook.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Sun, 1 Nov 2020 08:52:12 +0000 (09:52 +0100)]
pack-write: use hashwrite_be32() instead of double-buffering array
hashwrite() already buffers writes, so pass the fanout table entries
individually via hashwrite_be32(), which also does the endianess
conversion for us. This avoids a memory copy, shortens the code and
reduces the number of magic numbers.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5411: finish preparing for `main` being the default branch name
In addition to the trivial search-and-replace performed over the course
of the previous three commits, there is one test in t5411 that depends
on the length of the default branch name.
Adjust it and use `main` as the default branch name in this test.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the previous commit, we adjusted roughly half of the support files,
to stay under the 100kB limit (mails larger than that are rejected by
the Git mailing list).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We do not convert the files in `t/t5411/` in one go because the patch
would be too big (mails larger than 100kB are rejected by the Git
mailing list). Instead, we start with roughly half of the support files.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a straight-forward search-and-replace in the test script;
However, this is not yet complete because it requires many more
replacements in `t/t5411/`, too many for a single patch (the Git mailing
list rejects mails larger than 100kB). For that reason, we disable this
test script temporarily via the `PREPARE_FOR_MAIN_BRANCH` prereq.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Sat, 31 Oct 2020 12:47:58 +0000 (13:47 +0100)]
bisect: clear flags in passed repository
69d2cfe6e8 (bisect.c: remove the_repository reference, 2018-11-10) kept
the implicit the_repository reference in clear_commit_marks_all, which
was made explicit by the previous commit (and which also renamed it to
repo_clear_commit_marks). Replace it as well.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Sat, 31 Oct 2020 12:46:08 +0000 (13:46 +0100)]
object: allow clear_commit_marks_all to handle any repo
Allow callers to specify the repository to use. Rename the function to
repo_clear_commit_marks to document its new scope. No functional change
intended.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Fri, 30 Oct 2020 20:04:24 +0000 (13:04 -0700)]
Merge branch 'cm/t7xxx-cleanup'
Micro clean-up.
* cm/t7xxx-cleanup:
t7102: prepare expected output inside test_expect_* block
t7201: put each command on a separate line
t7201: use 'git -C' to avoid subshell
t7102,t7201: remove whitespace after redirect operator
t7102,t7201: remove unnecessary blank spaces in test body
t7101,t7102,t7201: modernize test formatting
Junio C Hamano [Thu, 29 Oct 2020 21:18:47 +0000 (14:18 -0700)]
Merge branch 'jk/committer-date-is-author-date-fix' into maint
In 2.29, "--committer-date-is-author-date" option of "rebase" and
"am" subcommands lost the e-mail address by mistake, which has been
corrected.
* jk/committer-date-is-author-date-fix:
rebase: fix broken email with --committer-date-is-author-date
am: fix broken email with --committer-date-is-author-date
t3436: check --committer-date-is-author-date result more carefully
Philippe Blain [Thu, 29 Oct 2020 12:48:29 +0000 (12:48 +0000)]
log, show: add tests for messages containing CRLF
A previous commit adjusted the code in ref-filter.c so that messages
containing CRLF are now correctly parsed and displayed.
Add tests to also check that `git log` and `git show` correctly handle
such messages, to prevent futur regressions if these commands are
refactored to use the ref-filter API.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Philippe Blain [Thu, 29 Oct 2020 12:48:28 +0000 (12:48 +0000)]
ref-filter: handle CRLF at end-of-line more gracefully
The ref-filter code does not correctly handle commit or tag messages
that use CRLF as the line terminator. Such messages can be created with
the `--cleanup=verbatim` option of `git commit` and `git tag`, or by
using `git commit-tree` directly.
The function `find_subpos` in ref-filter.c looks for two consecutive
LFs to find the end of the subject line, a sequence which is absent in
messages using CRLF. This results in the whole message being parsed as
the subject line (`%(contents:subject)`), and the body of the message
(`%(contents:body)`) being empty.
Moreover, in `copy_subject`, which wants to return the subject as a
single line, '\n' is replaced by space, but '\r' is
untouched.
This impacts the output of `git branch`, `git tag` and `git
for-each-ref`.
This behaviour is a regression for `git branch --verbose`, which
bisects down to 949af0684c (branch: use ref-filter printing APIs,
2017-01-10).
Adjust the ref-filter code to be more lenient by hardening the logic in
`copy_subject` and `find_subpos` to correctly parse messages containing
CRLF.
Add a new test script, 't3920-crlf-messages.sh', to test the behaviour
of commands using either the ref-filter or the pretty APIs with messages
using CRLF line endings. The function `test_crlf_subject_body_and_contents`
can be used to test that the `--format` option of `branch`, `tag`,
`for-each-ref`, `log` and `show` correctly displays the subject, body
and raw content of commit and tag messages using CRLF. Test the
output of `branch`, `tag` and `for-each-ref` with such commits.
Helped-by: Junio C Hamano <gitster@pobox.com> Helped-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Wed, 28 Oct 2020 09:33:24 +0000 (05:33 -0400)]
sideband: diagnose more sideband anomalies
In demultiplex_sideband(), there are two oddities when we check an
incoming packet:
- if it has zero length, then we assume it's a flush packet. This
means we fail to notice the difference between a real flush and a
true zero-length packet that's missing its sideband designator. It's
not a huge problem in practice because we'd never send a zero-length
data packet (even our keepalives are otherwise-empty sideband-1
packets).
But it would be nice to detect and report the error, since it's
likely to cause other confusion (we think the other side flushed,
but they do not).
- we try to detect packets missing their designator by checking for
"if (len < 1)". But this will never trigger for "len == 0"; we've
already detected that and left the function before then.
It _could_ detect a negative "len" parameter. But in that case, the
error message is wrong. The issue is not "no sideband" but rather
"eof while reading the packet". However, this can't actually be
triggered in practice, because neither of the two callers uses
pkt_read's GENTLE_ON_EOF flag. Which means they'd die with "the
remote end hung up unexpectedly" before we even get here.
So this truly is dead code.
We can improve these cases by passing in a pkt-line status to the
demultiplexer, and by having recv_sideband() use GENTLE_ON_EOF. This
gives us two improvements:
- we can now reliably detect flush packets, and will report a normal
packet missing its sideband designator as an error
- we'll report an eof with a more detailed "protocol error: eof while
reading sideband packet", rather than the generic "the remote end
hung up unexpectedly"
- when we see an eof, we'll flush the sideband scratch buffer, which
may provide some hints from the remote about why they hung up
(though note we already flush on newlines, so it's likely that most
such messages already made it through)
In some sense this patch goes against fbd76cd450 (sideband: reverse its
dependency on pkt-line, 2019-01-16), which caused the sideband code not
to depend on the pkt-line code. But that commit was really just trying
to deal with the circular header dependency. The two modules are
conceptually interlinked, and it was just trying to keep things
compiling. And indeed, there's a sticking point in this patch: because
pkt-line.h includes sideband.h, we can't add the reverse include we need
for the sideband code to have an "enum packet_read_status" parameter.
Nor can we forward declare it, because you can't forward declare an enum
in C. However, C does guarantee that enums fit in an int, so we can just
use that type.
One alternative would be for the callers to check themselves that they
got something sane from the pkt-line code. But besides duplicating
logic, this gets quite tricky. Any error condition requires flushing the
sideband #2 scratch buffer, which only demultiplex_sideband() knows how
to do.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>