Fix numerous and mostly long-standing segfaults in consumers of
the *_config_*value_multi() API. As discussed in the preceding commit
an empty key in the config syntax yields a "NULL" string, which these
users would give to strcmp() (or similar), resulting in segfaults.
As this change shows, most users users of the *_config_*value_multi()
API didn't really want such an an unsafe and low-level API, let's give
them something with the safety of git_config_get_string() instead.
This fix is similar to what the *_string() functions and others
acquired in[1] and [2]. Namely introducing and using a safer
"*_get_string_multi()" variant of the low-level "_*value_multi()"
function.
This fixes segfaults in code introduced in:
- d811c8e17c (versionsort: support reorder prerelease suffixes, 2015-02-26)
- c026557a37 (versioncmp: generalize version sort suffix reordering, 2016-12-08)
- a086f921a7 (submodule: decouple url and submodule interest, 2017-03-17)
- a6be5e6764 (log: add log.excludeDecoration config option, 2020-04-16)
- 92156291ca (log: add default decoration filter, 2022-08-05)
- 50a044f1e4 (gc: replace config subprocesses with API calls, 2022-09-27)
There are now two users ofthe low-level API:
- One in "builtin/for-each-repo.c", which we'll convert in a
subsequent commit.
- The "t/helper/test-config.c" code added in [3].
As seen in the preceding commit we need to give the
"t/helper/test-config.c" caller these "NULL" entries.
We could also alter the underlying git_configset_get_value_multi()
function to be "string safe", but doing so would leave no room for
other variants of "*_get_value_multi()" that coerce to other types.
Such coercion can't be built on the string version, since as we've
established "NULL" is a true value in the boolean context, but if we
coerced it to "" for use in a list of strings it'll be subsequently
coerced to "false" as a boolean.
The callback pattern being used here will make it easy to introduce
e.g. a "multi" variant which coerces its values to "bool", "int",
"path" etc.
1. 40ea4ed903 (Add config_error_nonbool() helper function,
2008-02-11)
2. 6c47d0e8f3 (config.c: guard config parser from value=NULL,
2008-02-11).
3. 4c715ebb96 (test-config: add tests for the config_set API,
2014-07-28)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Have the "git_configset_get_value_multi()" function and its siblings
return an "int" and populate a "**dest" parameter like every other
git_configset_get_*()" in the API.
As we'll take advantage of in subsequent commits, this fixes a blind
spot in the API where it wasn't possible to tell whether a list was
empty from whether a config key existed. For now we don't make use of
those new return values, but faithfully convert existing API users.
Most of this is straightforward, commentary on cases that stand out:
- To ensure that we'll properly use the return values of this function
in the future we're using the "RESULT_MUST_BE_USED" macro introduced
in [1].
As git_die_config() now has to handle this return value let's have
it BUG() if it can't find the config entry. As tested for in a
preceding commit we can rely on getting the config list in
git_die_config().
- The loops after getting the "list" value in "builtin/gc.c" could
also make use of "unsorted_string_list_has_string()" instead of using
that loop, but let's leave that for now.
- In "versioncmp.c" we now use the return value of the functions,
instead of checking if the lists are still non-NULL.
1. 1e8697b5c4 (submodule--helper: check repo{_submodule,}_init()
return values, 2022-09-01),
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor the reading of the versionSort.suffix and
versionSort.prereleaseSuffix configuration variables to stay within
the bounds of our CodingGuidelines when it comes to line length, and
to avoid repeating ourselves.
Renaming "deprecated_prereleases" to "oldl" doesn't help us to avoid
line wrapping now, but it will in a subsequent commit.
Let's also split out the names of the config variables into variables
of our own, and refactor the nested if/else to avoid indenting it, and
the existing bracing style issue.
This all helps with the subsequent commit, where we'll need to start
checking different git_config_get_value_multi() return value. See
c026557a37 (versioncmp: generalize version sort suffix reordering,
2016-12-08) for the original implementation of most of this.
Moving the "initialized = 1" assignment allows us to move some of this
to the variable declarations in the subsequent commit.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Stop including config.h by default in cache.h. Instead only include
config.h in those files which require use of the config system.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'versionsort.prereleaseSuffix' configuration variable, as its name
suggests, is supposed to only deal with tagnames with prerelease
suffixes, and allows sorting those prerelease tags in a user-defined
order before the suffixless main release tag, instead of sorting them
simply lexicographically.
However, the previous changes in this series resulted in an
interesting and useful property of version sort:
- The empty string as a configured suffix matches all tagnames,
including tagnames without any suffix, but
- tagnames containing a "real" configured suffix are still ordered
according to that real suffix, because any longer suffix takes
precedence over the empty string.
Exploiting this property we can easily generalize suffix reordering
and specify the order of tags with given suffixes not only before but
even after a main release tag by using the empty suffix to denote the
position of the main release tag, without any algorithm changes:
$ git -c versionsort.prereleaseSuffix=-alpha \
-c versionsort.prereleaseSuffix=-beta \
-c versionsort.prereleaseSuffix="" \
-c versionsort.prereleaseSuffix=-gamma \
-c versionsort.prereleaseSuffix=-delta \
tag -l --sort=version:refname 'v3.0*'
v3.0-alpha1
v3.0-beta1
v3.0
v3.0-gamma1
v3.0-delta1
Since 'versionsort.prereleaseSuffix' is not a fitting name for a
configuration variable to control this more general suffix reordering,
introduce the new variable 'versionsort.suffix'. Still keep the old
configuration variable name as a deprecated alias, though, to avoid
suddenly breaking setups already using it. Ignore the old variable if
both old and new configuration variables are set, but emit a warning
so users will be aware of it and can fix their configuration. Extend
the documentation to describe and add a test to check this more
general behavior.
Note: since the empty suffix matches all tagnames, tagnames with
suffixes not included in the configuration are listed together with
the suffixless main release tag, ordered lexicographically right after
that, i.e. before tags with suffixes listed in the configuration
following the empty suffix.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As the number of identical steps to be done for both tagnames grows,
extract them into a helper function, with the additional benefit that
the conditionals near the end of swap_prereleases() will use more
meaningful variable names.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When comparing tagnames, it is possible that a tagname contains more
than one of the configured prerelease suffixes around the first
different character. After fixing a bug in the previous commit such a
tagname is sorted according to the contained suffix which comes first
in the configuration. This is, however, not quite the right thing to
do in the following corner cases:
1. $ git -c versionsort.suffix=-bar
-c versionsort.suffix=-foo-baz
-c versionsort.suffix=-foo-bar
tag -l --sort=version:refname 'v1*'
v1.0-foo-bar
v1.0-foo-baz
The suffix of the tagname 'v1.0-foo-bar' is clearly '-foo-bar',
so it should be listed last. However, as it also contains '-bar'
around the first different character, it is listed first instead,
because that '-bar' suffix comes first the configuration.
2. One of the configured suffixes starts with the other:
$ git -c versionsort.prereleasesuffix=-pre \
-c versionsort.prereleasesuffix=-prerelease \
tag -l --sort=version:refname 'v2*'
v2.0-prerelease1
v2.0-pre1
v2.0-pre2
Here the tagname 'v2.0-prerelease1' should be the last. When
comparing 'v2.0-pre1' and 'v2.0-prerelease1' the first different
characters are '1' and 'r', respectively. Since this first
different character must be part of the configured suffix, the
'-pre' suffix is not recognized in the first tagname. OTOH, the
'-prerelease' suffix is properly recognized in
'v2.0-prerelease1', thus it is listed first.
Improve version sort in these corner cases, and
- look for a configured prerelease suffix containing the first
different character or ending right before it, so the '-pre'
suffixes are recognized in case (2). This also means that
when comparing tagnames 'v2.0-pre1' and 'v2.0-pre2',
swap_prereleases() would find the '-pre' suffix in both, but then
it will return "undecided" and the caller will do the right thing
by sorting based in '1' and '2'.
- If the tagname contains more than one suffix, then give precedence
to the contained suffix that starts at the earliest offset in the
tagname to address (1).
- If there are more than one suffixes starting at that earliest
position, then give precedence to the longest of those suffixes,
thus ensuring that in (2) the tagname 'v2.0-prerelease1' won't be
sorted based on the '-pre' suffix.
Add tests for these corner cases and adjust the documentation
accordingly.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Version sort with prerelease reordering sometimes puts tagnames in the
wrong order, when the common part of two compared tagnames overlaps
with the leading character(s) of one or more configured prerelease
suffixes. Note the position of "v2.1.0-beta-1":
$ git -c versionsort.prereleaseSuffix=-beta \
tag -l --sort=version:refname v2.1.*
v2.1.0-beta-2
v2.1.0-beta-3
v2.1.0
v2.1.0-RC1
v2.1.0-RC2
v2.1.0-beta-1
v2.1.1
v2.1.2
The reason is that when comparing a pair of tagnames, first
versioncmp() looks for the first different character in a pair of
tagnames, and then the swap_prereleases() helper function looks for a
configured prerelease suffix _starting at_ that character. Thus, when
in the above example the sorting algorithm happens to compare the
tagnames "v2.1.0-beta-1" and "v2.1.0-RC2", swap_prereleases() tries to
match the suffix "-beta" against "beta-1" to no avail, and the two
tagnames erroneously end up being ordered lexicographically.
To fix this issue change swap_prereleases() to look for configured
prerelease suffixes _containing_ the position of that first different
character.
Care must be taken, when a configured suffix is longer than the
tagnames' common part up to the first different character, to avoid
reading memory before the beginning of the tagnames. Add a test that
uses an exceptionally long prerelease suffix to check for this, in the
hope that in case of a regression the illegal memory access causes a
segfault in 'git tag' on one of the commonly used platforms (the test
happens to pass successfully on my Linux system with the safety check
removed), or at least makes valgrind complain.
Under some circumstances it's possible that more than one prerelease
suffixes can be found in the same tagname around that first different
character. With this simple bugfix patch such a tagname is sorted
according to the contained suffix that comes first in the
configuration for now. This is less than ideal in some cases, and the
following patch will take care of those.
Reported-by: Leho Kraav <leho@conversionready.com>
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The swap_prereleases() helper function is responsible for finding
configured prerelease suffixes in a pair of tagnames to be compared,
but this function currently gets to see only the parts of those two
tagnames starting at the first different character. To fix some
issues related to the common part of two tagnames overlapping with
leading part of a prerelease suffix, this helper function must see
both full tagnames.
In preparation for the fix in the following patch, refactor
swap_prereleases() and its caller to pass two full tagnames and an
additional offset indicating the position of the first different
character.
While updating the comment describing that function, remove the
sentence about not dealing with both tagnames having the same suffix.
Currently it doesn't add much value (we know that there is a different
character, so it's obvious that it can't possibly be the same suffix
in both), and at the end of this patch series it won't even be true
anymore.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
--sort=version:refname (or --sort=v:refname for short) sorts tags as
if they are versions. --sort=-refname reverses the order (with or
without ":version").
versioncmp() is copied from string/strverscmp.c in glibc commit
ee9247c38a8def24a59eb5cfb7196a98bef8cfdc, reformatted to Git coding
style. The implementation is under LGPL-2.1 and according to [1] I can
relicense it to GPLv2.
[1] http://www.gnu.org/licenses/gpl-faq.html#AllCompatibility
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
