GCC 15 compatibility updates.
* jk/gcc15:
object-file: inline empty tree and blob literals
object-file: treat cached_object values as const
object-file: drop oid field from find_cached_object() return value
object-file: move empty_tree struct into find_cached_object()
object-file: drop confusing oid initializer of empty_tree struct
object-file: prefer array-of-bytes initializer for hash literals
Fix for clar unit tests to support CMake build.
* ps/clar-build-improvement:
Makefile: let clar header targets depend on their scripts
cmake: use verbatim arguments when invoking clar commands
cmake: use SH_EXE to execute clar scripts
t/unit-tests: convert "clar-generate.awk" into a shell script
Documentation for "git bundle" saw improvements to more prominently
call out the use of '--all' when creating bundles.
* kh/bundle-docs:
Documentation/git-bundle.txt: discuss naïve backups
Documentation/git-bundle.txt: mention --all in spec. refs
Documentation/git-bundle.txt: remove old `--all` example
Documentation/git-bundle.txt: mention full backup example
Code clean-up.
* jk/output-prefix-cleanup:
diff: store graph prefix buf in git_graph struct
diff: return line_prefix directly when possible
diff: return const char from output_prefix callback
diff: drop line_prefix_length field
line-log: use diff_line_prefix() instead of custom helper
Doc update to clarify how periodical maintenance are scheduled,
spread across time to avoid thundering hurds.
* sk/doc-maintenance-schedule:
doc: add a note about staggering of maintenance
* 'master' of https://github.com/j6t/gitk:
Makefile(s): avoid recipe prefix in conditional statements
doc: switch links to https
doc: update links to current pages
In GNU Make commit 07fcee35 ([SV 64815] Recipe lines cannot contain
conditional statements, 2023-05-22) and following, conditional
statements may no longer be preceded by a tab character (which Make
refers to as the recipe prefix).
There are a handful of spots in our various Makefile(s) which will break
in a future release of Make containing 07fcee35. For instance, trying to
compile the pre-image of this patch with the tip of make.git results in
the following:
$ make -v | head -1 && make
GNU Make 4.4.90
config.mak.uname:842: *** missing 'endif'. Stop.
The kernel addressed this issue in 82175d1f9430 (kbuild: Replace tabs
with spaces when followed by conditionals, 2024-01-28). Address the
issues in Git's tree by applying the same strategy.
When a conditional word (ifeq, ifneq, ifdef, etc.) is preceded by one or
more tab characters, replace each tab character with 8 space characters
with the following:
find . -type f -not -path './.git/*' -name Makefile -or -name '*.mak' |
xargs perl -i -pe '
s/(\t+)(ifn?eq|ifn?def|else|endif)/" " x (length($1) * 8) . $2/ge unless /\\$/
'
The "unless /\\$/" removes any false-positives (like "\telse \"
appearing within a shell script as part of a recipe).
After doing so, Git compiles on newer versions of Make:
$ make -v | head -1 && make
GNU Make 4.4.90
GIT_VERSION = 2.44.0.414.gfac1dc44ca9
[...]
$ echo $?
0
Reported-by: Dario Gjorgjevski <dario.gjorgjevski@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Cherry-picked-from: 728b9ac0c3
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
These sites offer https versions of their content.
Using the https versions provides some protection for users.
Signed-off-by: Josh Soref <jsoref@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Cherry-picked-from: d05b08cd52
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
It's somewhat traditional to respect sites' self-identification.
Signed-off-by: Josh Soref <jsoref@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Cherry-picked-from: 65175d9ea2
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Object reuse code based on multi-pack-index sent an unwanted copy
of object.
* tb/multi-pack-reuse-dupfix:
pack-objects: only perform verbatim reuse on the preferred pack
t5332-multi-pack-reuse.sh: demonstrate duplicate packing failure
Double-free fix.
* jk/fetch-prefetch-double-free-fix:
refspec: store raw refspecs inside refspec_item
refspec: drop separate raw_nr count
fetch: adjust refspec->raw_nr when filtering prefetch refspecs
Avoid build/test breakage on a system without working malloc debug
support dynamic library.
* jk/test-malloc-debug-check:
test-lib: move malloc-debug setup after $PATH setup
test-lib: check malloc debug LD_PRELOAD before using
"git gc" discards any objects that are outside promisor packs that
are referred to by an object in a promisor pack, and we do not
refetch them from the promisor at runtime, resulting an unusable
repository. Work it around by including these objects in the
referring promisor pack at the receiving end of the fetch.
* jt/repack-local-promisor:
index-pack: repack local links into promisor packs
t5300: move --window clamp test next to unclamped
t0410: use from-scratch server
t0410: make test description clearer
A "git fetch" from the superproject going down to a submodule used
a wrong remote when the default remote names are set differently
between them.
* db/submodule-fetch-with-remote-name-fix:
submodule: correct remote name with fetch
Fail gracefully instead of crashing when attempting to write the
contents of a corrupt in-core index as a tree object.
* ps/cache-tree-w-broken-index-entry:
unpack-trees: detect mismatching number of cache-tree/index entries
cache-tree: detect mismatching number of index entries
cache-tree: refactor verification to return error codes
"git maintenance start" crashed due to an uninitialized variable
reference, which has been corrected.
* ps/maintenance-start-crash-fix:
builtin/gc: fix crash when running `git maintenance start`
On macOS, fsmonitor can fall into a race condition that results in
a client waiting forever to be notified for an event that have
already happened. This problem has been corrected.
* jk/fsmonitor-event-listener-race-fix:
fsmonitor: initialize fs event listener before accepting clients
simple-ipc: split async server initialization and running
Use after free and double freeing at the end in "git log -L... -p"
had been identified and fixed.
* ds/line-log-asan-fix:
line-log: protect inner strbuf from free
We define macros with the bytes of the empty trees and blobs for sha1
and sha256. But since e1ccd7e2b1 (sha1_file: only expose empty object
constants through git_hash_algo, 2018-05-02), those are used only for
initializing the git_hash_algo entries. Any other code using the macros
directly would be suspicious, since a hash_algo pointer is the level of
indirection we use to make everything work with both sha1 and sha256.
So let's future proof against code doing the wrong thing by dropping the
macros entirely and just initializing the structs directly.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The cached-object API maps oids to in-memory entries. Once inserted,
these entries should be immutable. Let's return them from the
find_cached_object() call with a const tag to make this clear.
Suggested-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The pretend_object_file() function adds to an array mapping oids to
object contents, which are later retrieved with find_cached_object().
We naturally need to store the oid for each entry, since it's the lookup
key.
But find_cached_object() also returns a hard-coded empty_tree object.
There we don't care about its oid field and instead compare against
the_hash_algo->empty_tree. The oid field is left as all-zeroes.
This all works, but it means that the cached_object struct we return
from find_cached_object() may or may not have a valid oid field, depend
whether it is the hard-coded tree or came from pretend_object_file().
Nobody looks at the field, so there's no bug. But let's future-proof it
by returning only the object contents themselves, not the oid. We'll
continue to call this "struct cached_object", and the array entry
mapping the key to those contents will be a "cached_object_entry".
This would also let us swap out the array for a better data structure
(like a hashmap) if we chose, but there's not much point. The only code
that adds an entry is git-blame, which adds at most a single entry per
process.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The fake empty_tree struct is a static global, but the only code that
looks at it is find_cached_object(). The struct itself is a little odd,
with an invalid "oid" field that is handled specially by that function.
Since it's really just an implementation detail, let's move it to a
static within the function. That future-proofs against other code trying
to use it and seeing the weird oid value.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We treat the empty tree specially, providing an in-memory "cached" copy,
which allows you to diff against it even if the object doesn't exist in
the repository. This is implemented as part of the larger cached_object
subsystem, but we use a stand-alone empty_tree struct.
We initialize the oid of that struct using EMPTY_TREE_SHA1_BIN_LITERAL.
At first glance, that seems like a bug; how could this ever work for
sha256 repositories?
The answer is that we never look at the oid field! The oid field is used
to look up entries added by pretend_object_file() to the cached_objects
array. But for our stand-alone entry, we look for it independently using
the_hash_algo->empty_tree, which will point to the correct algo struct
for the repository.
This happened in 62ba93eaa9 (sha1_file: convert cached object code to
struct object_id, 2018-05-02), which even mentions that this field is
never used. Let's reduce confusion for anybody reading this code by
replacing the sha1 initializer with a comment. The resulting field will
be all-zeroes, so any violation of our assumption that the oid field is
not used will break equally for sha1 and sha256.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We hard-code a few well-known hash values for empty trees and blobs in
both sha1 and sha256 formats. We do so with string literals like this:
#define EMPTY_TREE_SHA256_BIN_LITERAL \
"\x6e\xf1\x9b\x41\x22\x5c\x53\x69\xf1\xc1" \
"\x04\xd4\x5d\x8d\x85\xef\xa9\xb0\x57\xb5" \
"\x3b\x14\xb4\xb9\xb9\x39\xdd\x74\xde\xcc" \
"\x53\x21"
and then use it to initialize the hash field of an object_id struct.
That hash field is exactly 32 bytes long (the size we need for sha256).
But the string literal above is actually 33 bytes long due to the NUL
terminator. This is legal in C, and the NUL is ignored.
Side note on legality: in general excess initializer elements are
forbidden, and gcc will warn on both of these:
char foo[3] = { 'h', 'u', 'g', 'e' };
char bar[3] = "VeryLongString";
I couldn't find specific language in the standard allowing
initialization from a string literal where _just_ the NUL is ignored,
but C99 section 6.7.8 (Initialization), paragraph 32 shows this exact
case as "example 8".
However, the upcoming gcc 15 will start warning for this case (when
compiled with -Wextra via DEVELOPER=1):
CC object-file.o
object-file.c:52:9: warning: initializer-string for array of ‘unsigned char’ is too long [-Wunterminated-string-initialization]
52 | "\x6e\xf1\x9b\x41\x22\x5c\x53\x69\xf1\xc1" \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
object-file.c:79:17: note: in expansion of macro ‘EMPTY_TREE_SHA256_BIN_LITERAL’
which is understandable. Even though this is not a bug for us, since we
do not care about the NUL terminator (and are just using the literal as
a convenient format), it would be easy to accidentally create an array
that was mistakenly unterminated.
We can avoid this warning by switching the initializer to an actual
array of unsigned values. That arguably demonstrates our intent more
clearly anyway.
Reported-by: Sam James <sam@gentoo.org>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The targets that generate clar headers depend on their source files, but
not on the script that is actually generating the output. Fix the issue
by adding the missing dependencies.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Pass the VERBATIM option to `add_custom_command()`. Like this, all
arguments to the commands will be escaped properly for the build tool so
that the invoked command receives each argument unchanged.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 30bf9f0aaa (cmake: set up proper dependencies for generated clar
headers, 2024-10-21), we have deduplicated the logic to generate our
clar headers by reusing the same scripts that our Makefile does. Despite
the deduplication, this refactoring also made us rebuild the headers in
case the source files change, which didn't happen previously.
The commit also introduced an issue though: we execute the scripts
directly, so when the host does not have "/bin/sh" available they will
fail. This is for example the case on Windows when importing the CMake
project into Microsoft Visual Studio.
Address the issue by invoking the scripts with `SH_EXE`, which contains
the discovered path of the shell interpreter.
While at it, wrap the overly long lines in the CMake build instructions.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert "clar-generate.awk" into a shell script that invokes awk(1).
This allows us to avoid the shell redirect in the build system, which
may otherwise be a problem with build systems on platforms that use a
different shell.
While at it, wrap the overly long lines in the CMake build instructions.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It might be naïve to think that those who need this education would end
up here in the first place. But I think it’s good to mention this
high-level concept here on a command which provides a backup strategy.
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
