As in previous commits, harden the wincred credential helper against the
aforementioned protocol injection attack.
Unlike the approached used for osxkeychain and libsecret, where a
fixed-size buffer was replaced with `getline()`, we must take a
different approach here. There is no `getline()` equivalent in Windows,
and the function is not available to us with ordinary compiler settings.
Instead, allocate a larger (still fixed-size) buffer in which to process
each line. The value of 100 KiB is chosen to match the maximum-length
header that curl will allow, CURL_MAX_HTTP_HEADER.
To ensure that we are reading complete lines at a time, and that we
aren't susceptible to a similar injection attack (albeit with more
padding), ensure that each read terminates at a newline (i.e., that no
line is more than 100 KiB long).
Note that it isn't sufficient to turn the old loop into something like:
while (len && strchr("\r\n", buf[len - 1])) {
buf[--len] = 0;
ends_in_newline = 1;
}
because if an attacker sends something like:
[aaaaa.....]\r
host=example.com\r\n
the credential helper would fill its buffer after reading up through the
first '\r', call fgets() again, and then see "host=example.com\r\n" on
its line.
Note that the original code was written in a way that would trim an
arbitrary number of "\r" and "\n" from the end of the string. We should
get only a single "\n" (since the point of `fgets()` is to return the
buffer to us when it sees one), and likewise would not expect to see
more than one associated "\r". The new code trims a single "\r\n", which
matches the original intent.
[1]: https://curl.se/libcurl/c/CURLOPT_HEADERFUNCTION.html
Tested-by: Matthew John Cheetham <mjcheetham@outlook.com>
Helped-by: Matthew John Cheetham <mjcheetham@outlook.com>
Co-authored-by: Jeff King <peff@peff.net>
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>
The libsecret credential helper reads the newline-delimited
protocol stream one line at a time by repeatedly calling fgets() into a
fixed-size buffer, and is thus affected by the vulnerability described
in the previous commit.
To mitigate this attack, avoid using a fixed-size buffer, and instead
rely on getline() to allocate a buffer as large as necessary to fit the
entire content of the line, preventing any protocol injection.
In most parts of Git we don't assume that every platform has getline().
But libsecret is primarily used on Linux, where we do already assume it
(using a knob in config.mak.uname). POSIX also added getline() in 2008,
so we'd expect other recent Unix-like operating systems to have it
(e.g., FreeBSD also does).
Note that the buffer was already allocated on the heap in this case, but
we'll swap `g_free()` for `free()`, since it will now be allocated by
the system `getline()`, rather than glib's `g_malloc()`.
Tested-by: Jeff King <peff@peff.net>
Co-authored-by: Jeff King <peff@peff.net>
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>
The libsecret credential helper does not mark its build artifact as
ignored, so running "make" results in a dirty working tree.
Mark the "git-credential-libsecret" binary as ignored to avoid the above.
Co-authored-by: Jeff King <peff@peff.net>
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>
libgnome-keyring was deprecated in 2014 (in favor of libsecret), more
than nine years ago [1].
The credential helper implemented using libgnome-keyring has had a small
handful of commits since 2013, none of which implemented or changed any
functionality. The last commit to do substantial work in this area was
15f7221686 (contrib/git-credential-gnome-keyring.c: support really
ancient gnome-keyring, 2013-09-23), just shy of nine years ago.
This credential helper suffers from the same `fgets()`-related injection
attack (using the new "wwwauth[]" feature) as in the previous commit.
Instead of patching it, let's remove this helper as deprecated.
[1]: https://mail.gnome.org/archives/commits-list/2014-January/msg01585.html
Co-authored-by: Jeff King <peff@peff.net>
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>
The macOS Keychain-based credential helper reads the newline-delimited
protocol stream one line at a time by repeatedly calling fgets() into a
fixed-size buffer, and is thus affected by the vulnerability described
in the previous commit.
To mitigate this attack, avoid using a fixed-size buffer, and instead
rely on getline() to allocate a buffer as large as necessary to fit the
entire content of the line, preventing any protocol injection.
We solved a similar problem in a5bb10fd5e (config: avoid fixed-sized
buffer when renaming/deleting a section, 2023-04-06) by switching to
strbuf_getline(). We can't do that here because the contrib helpers do
not link with the rest of Git, and so can't use a strbuf. But we can use
the system getline() directly, which works similarly.
In most parts of Git we don't assume that every platform has getline().
But this helper is run only on OS X, and that platform added support in
10.7 ("Lion") which was released in 2011.
Tested-by: Taylor Blau <me@ttaylorr.com>
Co-authored-by: Jeff King <peff@peff.net>
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>
Add a test ensuring that the "wwwauth[]" field cannot be used to
inject malicious data into the credential helper stream.
Many of the credential helpers in contrib/credential read the
newline-delimited protocol stream one line at a time by repeatedly
calling fgets() into a fixed-size buffer.
This assumes that each line is no more than 1024 characters long, since
each iteration of the loop assumes that it is parsing starting at the
beginning of a new line in the stream. However, similar to a5bb10fd5e
(config: avoid fixed-sized buffer when renaming/deleting a section,
2023-04-06), if a line is longer than 1024 characters, a malicious actor
can embed another command within an existing line, bypassing the usual
checks introduced in 9a6bbee800 (credential: avoid writing values with
newlines, 2020-03-11).
As with the problem fixed in that commit, specially crafted input can
cause the helper to return the credential for the wrong host, letting an
attacker trick the victim into sending credentials for one host to
another.
Luckily, all parts of the credential helper protocol that are available
in a tagged release of Git are immune to this attack:
- "protocol" is restricted to known values, and is thus immune.
- "host" is immune because curl will reject hostnames that have a '='
character in them, which would be required to carry out this attack.
- "username" is immune, because the buffer characters to fill out the
first `fgets()` call would pollute the `username` field, causing the
credential helper to return nothing (because it would match a
username if present, and the username of the credential to be stolen
is likely not 1024 characters).
- "password" is immune because providing a password instructs
credential helpers to avoid filling credentials in the first place.
- "path" is similar to username; if present, it is not likely to match
any credential the victim is storing. It's also not enabled by
default; the victim would have to set credential.useHTTPPath
explicitly.
However, the new "wwwauth[]" field introduced via 5f2117b24f
(credential: add WWW-Authenticate header to cred requests, 2023-02-27)
can be used to inject data into the credential helper stream. For
example, running:
{
printf 'HTTP/1.1 401\r\n'
printf 'WWW-Authenticate: basic realm='
perl -e 'print "a" x 1024'
printf 'host=victim.com\r\n'
} | nc -Nlp 8080
in one terminal, and then:
git clone http://localhost:8080
in another would result in a line like:
wwwauth[]=basic realm=aaa[...]aaahost=victim.com
being sent to the credential helper. If we tweak that "1024" to align
our output with the helper's buffer size and the rest of the data on the
line, it can cause the helper to see "host=victim.com" on its own line,
allowing motivated attackers to exfiltrate credentials belonging to
"victim.com".
The below test demonstrates these failures and provides us with a test
to ensure that our fix is correct. That said, it has a couple of
shortcomings:
- it's in t0303, since that's the only mechanism we have for testing
random helpers. But that means nobody is going to run it under
normal circumstances.
- to get the attack right, it has to line up the stuffed name with the
buffer size, so we depend on the exact buffer size. I parameterized
it so it could be used to test other helpers, but in practice it's
not likely for anybody to do that.
Still, it's the best we can do, and will help us confirm the presence of
the problem (and our fixes) in the new few patches.
Co-authored-by: Jeff King <peff@peff.net>
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>
Teach git-credential to read "wwwauth[]" value(s) when parsing the
output of a credential helper.
These extra headers are not needed for Git's own HTTP support to use the
feature internally, but the feature would not be available for a
scripted caller (say, git-remote-mediawiki providing the header in the
same way).
As a bonus, this also makes it easier to use wwwauth[] in synthetic
credential inputs in our test suite.
Co-authored-by: Jeff King <peff@peff.net>
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>
The email format does not allow blank lines in headers; detect such
input and report it as malformed and add a test for it.
Signed-off-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Sometimes, adding a header different than CC or TO is desirable; for
example, when using Debbugs, it is best to use 'X-Debbugs-Cc' headers
to keep people in CC; this is an example use case enabled by the new
'--header-cmd' option.
The header unfolding logic is extracted to a subroutine so that it can
be reused; a test is added for coverage.
Signed-off-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This refactor is to pave the way for the addition of the new
'--header-cmd' option to the send-email command.
Signed-off-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The file started out as a test for picks and reverts with renames, but
has been subsequently populated with all kinds of basic tests, in
accordance with its generic name. Adjust the description to reflect
that.
Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "%GT" placeholder for the "--format" option of "git log" and
friends caused BUG() to trigger on a commit signed with an unknown
key, which has been corrected.
* jk/gpg-trust-level-fix:
gpg-interface: set trust level of missing key to "undefined"
When "gc" needs to retain unreachable objects, packing them into
cruft packs (instead of exploding them into loose object files) has
been offered as a more efficient option for some time. Now the use
of cruft packs has been made the default and no longer considered
an experimental feature.
* tb/enable-cruft-packs-by-default:
repository.h: drop unused `gc_cruft_packs`
builtin/gc.c: make `gc.cruftPacks` enabled by default
t/t9300-fast-import.sh: prepare for `gc --cruft` by default
t/t6500-gc.sh: add additional test cases
t/t6500-gc.sh: refactor cruft pack tests
t/t6501-freshen-objects.sh: prepare for `gc --cruft` by default
t/t5304-prune.sh: prepare for `gc --cruft` by default
builtin/gc.c: ignore cruft packs with `--keep-largest-pack`
builtin/repack.c: fix incorrect reference to '-C'
pack-write.c: plug a leak in stage_tmp_packfiles()
Support for "less secure apps" ended May 30, 2022.
This effectively reverts 155067a (git-send-email.txt: mention less secure
app access with Gmail, 2021-01-08).
Signed-off-by: Jouke Witteveen <j.witteveen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These are conscious violations of the usual rules for error messages,
based on this reasoning:
- If an error message is directly followed by another sentence, it
needs to be properly terminated with a period, lest the grammar
looks broken and becomes hard to read.
- That second sentence isn't actually an error message any more, so
it should abide to conventional language rules for good looks and
legibility. Arguably, these should be converted to advice
messages (which the user can squelch, too), but that's a much
bigger effort to get right.
- Neither of these apply to the first hunk in do_exec(), but this
two-line message looks just too much like a real sentence to not
terminate it. Also, leaving it alone would make it asymmetrical
to the other hunk.
Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
N_() is meant to be used on strings that are subsequently _()'d, which
isn't the case here.
The affected construct is a bit questionable from an i18n perspective,
as it pieces together a sentence from separate strings. However, it
doesn't appear to be that bad, as the "assembly instructions" are in a
translatable message as well. Lacking specific complaints from
translators, it doesn't seem worth changing this.
Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of the time the formatter was run, show the timestamp
recorded in the commit in the documentation.
* fc/doc-use-datestamp-in-commit:
doc: set actual revdate for manpages
The on-disk reverse index that allows mapping from the pack offset
to the object name for the object stored at the offset has been
enabled by default.
* tb/pack-revindex-on-disk:
t: invert `GIT_TEST_WRITE_REV_INDEX`
config: enable `pack.writeReverseIndex` by default
pack-revindex: introduce `pack.readReverseIndex`
pack-revindex: introduce GIT_TEST_REV_INDEX_DIE_ON_DISK
pack-revindex: make `load_pack_revindex` take a repository
t5325: mark as leak-free
pack-write.c: plug a leak in stage_tmp_packfiles()
The previous few commits improved the parsing of dates in malformed
commit objects. But there's one big case left implicit: we may still
feed garbage to parse_timestamp(). This is preferable to trying to be
more strict, but let's document the thinking in a comment.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The comment in parse_commit_date() claims that parse_timestamp() will
not walk past the end of the buffer we've been given, since it will hit
the newline at "eol" and stop. This is usually true, when dateptr
contains actual numbers to parse. But with a line like:
committer name <email> \n
with just whitespace, and no numbers, parse_timestamp() will consume
that newline as part of the leading whitespace, and we may walk past our
"tail" pointer (which itself is set from the "size" parameter passed in
to parse_commit_buffer()).
In practice this can't cause us to walk off the end of an array, because
we always add an extra NUL byte to the end of objects we load from disk
(as a defense against exactly this kind of bug). However, you can see
the behavior in action when "committer" is the final header (which it
usually is, unless there's an encoding) and the subject line can be
parsed as an integer. We walk right past the newline on the committer
line, as well as the "\n\n" separator, and mistake the subject for the
timestamp.
We can solve this by trimming the whitespace ourselves, making sure that
it has some non-whitespace to parse. Note that we need to be a bit
careful about the definition of "whitespace" here, as our isspace()
doesn't match exotic characters like vertical tab or formfeed. We can
work around that by checking for an actual number (see the in-code
comment). This is slightly more restrictive than the current code, but
in practice the results are either the same (we reject "foo" as "0", but
so would parse_timestamp()) or extremely unlikely even for broken
commits (parse_timestamp() would allow "\v123" as "123", but we'll now
make it "0").
I did also allow "-" here, which may be controversial, as we don't
currently support negative timestamps. My reasoning was two-fold. One,
the design of parse_timestamp() is such that we should be able to easily
switch it to handling signed values, and this otherwise creates a
hard-to-find gotcha that anybody doing that work would get tripped up
on. And two, the status quo is that we currently parse them, though the
result of course ends up as a very large unsigned value (which is likely
to just get clamped to "0" for display anyway, since our date routines
can't handle it).
The new test checks the commit parser (via "--until") for both vanilla
spaces and the vertical-tab case. I also added a test to check these
against the pretty-print formatter, which uses split_ident_line(). It's
not subject to the same bug, because it already insists that there be
one or more digits in the timestamp.
Helped-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To find the committer timestamp, we parse left-to-right looking for the
closing ">" of the email, and then expect the timestamp right after
that. But we've seen some broken cases in the wild where this fails, but
we _could_ find the timestamp with a little extra work. E.g.:
Name <Name<email>> 123456789 -0500
This means that features that rely on the committer timestamp, like
--since or --until, will treat the commit as happening at time 0 (i.e.,
1970).
This is doubly confusing because the pretty-print parser learned to
handle these in 03818a4a94 (split_ident: parse timestamp from end of
line, 2013-10-14). So printing them via "git show", etc, makes
everything look normal, but --until, etc are still broken (despite the
fact that that commit explicitly mentioned --until!).
So let's use the same trick as 03818a4a94: find the end of the line, and
parse back to the final ">". In theory we could use split_ident_line()
here, but it's actually a bit more strict. In particular, it requires a
valid time-zone token, too. That should be present, of course, but we
wouldn't want to break --until for cases that are working currently.
We might want to teach split_ident_line() to become more lenient there,
but it would require checking its many callers (since right now they can
assume that if date_start is non-NULL, so is tz_start).
So for now we'll just reimplement the same trick in the commit parser.
The test is in t4212, which already covers similar cases, courtesy of
03818a4a94. We'll just adjust the broken commit to munge both the author
and committer timestamps. Note that we could match (author|committer)
here, but alternation can't be used portably in sed. Since we wouldn't
expect to see ">" except as part of an ident line, we can just match
that character on any line.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We wouldn't expect cat-file to fail here, but it's good practice to
avoid putting git on the upstream of a pipe, as we otherwise ignore its
exit code.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
`strtok()` has a couple of drawbacks that make it undesirable to have
any new instances. In addition to being thread-unsafe, it also
encourages confusing data flows, where `strtok()` may be called from
multiple functions with its first argument as NULL, making it unclear
from the immediate context which string is being tokenized.
Now that we have removed all instances of `strtok()` from the tree,
let's ban `strtok()` to avoid introducing new ones in the future. If new
callers should arise, they are encouraged to use
`string_list_split_in_place()` (and `string_list_remove_empty_items()`,
if applicable).
string_list_split_in_place() is not a perfect drop-in replacement
for `strtok_r()`, particularly if the caller is processing a string with
an arbitrary number of tokens, and wants to process each token one at a
time.
But there are no instances of this in Git's tree which are more
well-suited to `strtok_r()` than the friendlier
`string_list_split_in_place()`, so ban `strtok_r()`, too.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The mark_common() method in negotiator/skipping.c was converted
from recursive to iterative in 4654134976 (negotiator/skipping:
avoid stack overflow, 2022-10-25), but there is some more work
to do:
1. prio_queue() should be used with clear_prio_queue(), otherwise there
will be a memory leak.
2. It does not do duplicate protection before prio_queue_put().
(The COMMON bit would work here, too.)
3. When it translated from recursive to iterative it kept "return"
statements that should probably be "continue" statements.
4. It does not attempt to parse commits, and instead returns
immediately when finding an unparsed commit. This is something
that it did in its original version, so maybe it is by design,
but it doesn't match the doc comment for the method.
Helped-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Han Xin <hanxin.hx@bytedance.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mark_common() in negotiator/default.c may overflow the stack due to
recursive function calls. Avoid this by instead recursing using a
heap-allocated data structure.
This is the same case as 4654134976 (negotiator/skipping: avoid
stack overflow, 2022-10-25)
Reported-by: Xin Xing <xingxin.xx@bytedance.com>
Signed-off-by: Han Xin <hanxin.hx@bytedance.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The version reported by e.g. x86_64-w64-mingw32-gcc on Debian bullseye
looks like:
gcc version 10-win32 20210110 (GCC)
This ends up with detect-compiler failing with:
./detect-compiler: 30: test: Illegal number: 10-win32
This change removes the two known suffixes known to exist in GCC versions
in Debian: -win32 and -posix.
Signed-off-by: Mike Hommey <mh@glandium.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The phrasing "is currently ignored" was prone to be misinterpreted
as if we were wishing if it were honored. Rephrase it to make it
clear that the experimental variable will be ignored.
In the longer term, after/when we allow incremental/over-the-wire
migration of the object-format, i.e. cloning from an SHA-1
repository to create an SHA-256 repository (or vice versa) and
fetching and pushing between them would bidirectionally convert the
object format on the fly, it is likely that we would teach a new
option "--object-format" to "git clone" to say "you would use
whatever object format the origin uses by default, but this time, I
am telling you to use this format on our side, doing on-the-fly
object format conversion as needed". So it is perfectly OK to
ignore the settings of this experimental variable, even after such
an extension happens that makes it necessary for us to have a way to
create a new repository that uses different object format from the
origin repository.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Geometric repacking ("git repack --geometric=<n>") in a repository
that borrows from an alternate object database had various corner
case bugs, which have been corrected.
* ps/fix-geom-repack-with-alternates:
repack: disable writing bitmaps when doing a local repack
repack: honor `-l` when calculating pack geometry
t/helper: allow chmtime to print verbosely without modifying mtime
pack-objects: extend test coverage of `--stdin-packs` with alternates
pack-objects: fix error when same packfile is included and excluded
pack-objects: fix error when packing same pack twice
pack-objects: split out `--stdin-packs` tests into separate file
repack: fix generating multi-pack-index with only non-local packs
repack: fix trying to use preferred pack in alternates
midx: fix segfault with no packs and invalid preferred pack
The sendemail-validate validate hook learned to pass the total
number of input files and where in the sequence each invocation is
via environment variables.
* rj/send-email-validate-hook-count-messages:
send-email: export patch counters in validate environment
The code to parse capability list for v0 on-wire protocol fell into
an infinite loop when a capability appears multiple times, which
has been corrected.
* jk/protocol-cap-parse-fix:
v0 protocol: use size_t for capability length/offset
t5512: test "ls-remote --heads --symref" filtering with v0 and v2
t5512: allow any protocol version for filtered symref test
t5512: add v2 support for "ls-remote --symref" test
v0 protocol: fix sha1/sha256 confusion for capabilities^{}
t5512: stop referring to "v1" protocol
v0 protocol: fix infinite loop when parsing multi-valued capabilities
Header clean-up.
* en/header-split-cache-h: (24 commits)
protocol.h: move definition of DEFAULT_GIT_PORT from cache.h
mailmap, quote: move declarations of global vars to correct unit
treewide: reduce includes of cache.h in other headers
treewide: remove double forward declaration of read_in_full
cache.h: remove unnecessary includes
treewide: remove cache.h inclusion due to pager.h changes
pager.h: move declarations for pager.c functions from cache.h
treewide: remove cache.h inclusion due to editor.h changes
editor: move editor-related functions and declarations into common file
treewide: remove cache.h inclusion due to object.h changes
object.h: move some inline functions and defines from cache.h
treewide: remove cache.h inclusion due to object-file.h changes
object-file.h: move declarations for object-file.c functions from cache.h
treewide: remove cache.h inclusion due to git-zlib changes
git-zlib: move declarations for git-zlib functions from cache.h
treewide: remove cache.h inclusion due to object-name.h changes
object-name.h: move declarations for object-name.c functions from cache.h
treewide: remove unnecessary cache.h inclusion
treewide: be explicit about dependence on mem-pool.h
treewide: be explicit about dependence on oid-array.h
...
Apply similar treatment as in the previous commit to remove usage of
`strtok()` from the "oidmap" test helper.
Each of the different commands that the "json-writer" helper accepts
pops the next space-delimited token from the current line and interprets
it as a string, integer, or double (with the exception of the very first
token, which is the command itself).
To accommodate this, split the line in place by the space character, and
pass the corresponding string_list to each of the specialized `get_s()`,
`get_i()`, and `get_d()` functions.
`get_i()` and `get_d()` are thin wrappers around `get_s()` that convert
their result into the appropriate type by either calling `strtol()` or
`strtod()`, respectively. In `get_s()`, we mark the token as "consumed"
by incrementing the `consumed_nr` counter, indicating how many tokens we
have read up to that point.
Because each of these functions needs the string-list parts, the number
of tokens consumed, and the line number, these three are wrapped up in
to a struct representing the line state.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply similar treatment as in the previous commit to remove usage of
`strtok()` from the "oidmap" test helper.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Avoid using the non-reentrant `strtok()` to separate the parts of each
incoming command. Instead of replacing it with `strtok_r()`, let's
instead use the more friendly pair of `string_list_split_in_place()` and
`string_list_remove_empty_items()`.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is sometimes useful to reduce the size of a `string_list`'s list of
items without having to re-allocate them. For example, doing the
following:
struct strbuf buf = STRBUF_INIT;
struct string_list parts = STRING_LIST_INIT_NO_DUP;
while (strbuf_getline(&buf, stdin) != EOF) {
parts.nr = 0;
string_list_split_in_place(&parts, buf.buf, ":", -1);
/* ... */
}
string_list_clear(&parts, 0);
is preferable over calling `string_list_clear()` on every iteration of
the loop. This is because `string_list_clear()` causes us free our
existing `items` array. This means that every time we call
`string_list_split_in_place()`, the string-list internals re-allocate
the same size array.
Since in the above example we do not care about the individual parts
after processing each line, it is much more efficient to pretend that
there aren't any elements in the `string_list` by setting `list->nr` to
0 while leaving the list of elements allocated as-is.
This allows `string_list_split_in_place()` to overwrite any existing
entries without needing to free and re-allocate them.
However, setting `list->nr` manually is not safe in all instances. There
are a couple of cases worth worrying about:
- If the `string_list` is initialized with `strdup_strings`,
truncating the list can lead to overwriting strings which are
allocated elsewhere. If there aren't any other pointers to those
strings other than the ones inside of the `items` array, they will
become unreachable and leak.
(We could ourselves free the truncated items between
string_list->items[nr] and `list->nr`, but no present or future
callers would benefit from this additional complexity).
- If the given `nr` is larger than the current value of `list->nr`,
we'll trick the `string_list` into a state where it thinks there are
more items allocated than there actually are, which can lead to
undefined behavior if we try to read or write those entries.
Guard against both of these by introducing a helper function which
guards assignment of `list->nr` against each of the above conditions.
Co-authored-by: Jeff King <peff@peff.net>
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>
Enhance `string_list_split_in_place()` to accept multiple characters as
delimiters instead of a single character.
Instead of using `strchr(2)` to locate the first occurrence of the given
delimiter character, `string_list_split_in_place_multi()` uses
`strcspn(2)` to move past the initial segment of characters comprised of
any characters in the delimiting set.
When only a single delimiting character is provided, `strpbrk(2)` (which
is implemented with `strcspn(2)`) has equivalent performance to
`strchr(2)`. Modern `strcspn(2)` implementations treat an empty
delimiter or the singleton delimiter as a special case and fall back to
calling strchrnul(). Both glibc[1] and musl[2] implement `strcspn(2)`
this way.
This change is one step to removing `strtok(2)` from the tree. Note that
`string_list_split_in_place()` is not a strict replacement for
`strtok()`, since it will happily turn sequential delimiter characters
into empty entries in the resulting string_list. For example:
string_list_split_in_place(&xs, "foo:;:bar:;:baz", ":;", -1)
would yield a string list of:
["foo", "", "", "bar", "", "", "baz"]
Callers that wish to emulate the behavior of strtok(2) more directly
should call `string_list_remove_empty_items()` after splitting.
To avoid regressions for the new multi-character delimter cases, update
t0063 in this patch as well.
[1]: https://sourceware.org/git/?p=glibc.git;a=blob;f=string/strcspn.c;hb=glibc-2.37#l35
[2]: https://git.musl-libc.org/cgit/musl/tree/src/string/strcspn.c?h=v1.2.3#n11
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the --contents option is used with git blame, and the contents of
the file have lines which can't be annotated by the history being
blamed, the user will see an author of "Not Committed Yet". This is
similar to the way blame handles working tree contents when blaming
without a revision.
This is slightly confusing since this data isn't the working copy and
while it is technically "not committed yet", its also coming from an
external file. Replace this author name with "External file
(--contents)" to better differentiate such lines from actual working
copy lines.
Suggested-by: Junio C Hamano <gitster@pobox.com>
Suggested-by: Glen Choo <chooglen@google.com>
Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are several tests in t1300-config.sh that validate failing
invocations of "git config". However, there are no tests that check
what happens when "git config" is asked to retrieve a value for a
missing key.
Add tests that check this for various combinations of "<section>.<key>"
and "<section>.<subsection>.<key>".
Signed-off-by: Andrei Rybak <rybak.a.v@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Tests "git config ignores pairs ..." in t1300-config.sh validate that
"git config" ignores various kinds of supplied pairs of environment
variables GIT_CONFIG_KEY_* GIT_CONFIG_VALUE_* depending on
GIT_CONFIG_COUNT. By "ignores" here we mean that "git config" abides by
the value of environment variable GIT_CONFIG_COUNT and doesn't use
key-value pairs outside of the supplied GIT_CONFIG_COUNT when trying to
produce a value for config key "pair.one".
These tests also validate that "git config" doesn't complain about
mismatched environment variables to standard error. This is validated
by redirecting the standard error to a file called "error" and asserting
that it is empty. However, two of these tests incorrectly redirect to
standard output while calling the file "error", and test 'git config
ignores pairs exceeding count' doesn't validate standard error at all.
Fix these tests by redirecting standard error to file "error" and
asserting its emptiness.
Signed-off-by: Andrei Rybak <rybak.a.v@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are two almost identical tests called 'git config ignores pairs
with zero count' in file t1300-config.sh. Drop the first of these and
keep the one that contains more assertions.
Signed-off-by: Andrei Rybak <rybak.a.v@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If some code sets up the data structures for a merge, but then never
actually performs one before calling merge_finalize(), then
merge_finalize() wouldn't notice that result->priv was NULL and
return early, resulting in following that NULL pointer and getting
a segfault. There is currently no code in the git codebase that does
this, but this issue was found during testing of some proposed patches
that had the following structure:
struct merge_options merge_opt;
struct merge_result result;
init_merge_options(&merge_opt, the_repository);
memset(&result, 0, sizeof(result));
<do N merges, for some value of N>
merge_finalize(&merge_opt, &result);
where some flags could cause the code to have N=0, i.e. doing no merges.
Add a check for result->priv being NULL and return early to avoid a
segfault in these kinds of cases.
While at it, ensure the FREE_AND_NULL() in the function does something
useful with the nulling aspect, namely sets result->priv to NULL rather
than a mere temporary.
Reported-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
