In most places that write files to the object database (even packfiles
via index-pack or fast-import), we use finalize_object_file(). This
prefers link()/unlink() over rename(), because it means we will prefer
data that is already in the repository to data that we are newly
writing.
We should do the same thing in pack-objects. Even though we don't think
of it as accepting outside data (and thus not being susceptible to
collision attacks), in theory a determined attacker could present just
the right set of objects to cause an incremental repack to generate
a pack with their desired hash.
This has some test and real-world fallout, as seen in the adjustment to
t5303 below. That test script assumes that we can "fix" corruption by
repacking into a good state, including when the pack generated by that
repack operation collides with a (corrupted) pack with the same hash.
This violates our assumption from the previous adjustments to
finalize_object_file() that if we're moving a new file over an existing
one, that since their checksums match, so too must their contents.
This makes "fixing" corruption like this a more explicit operation,
since the test (and users, who may fix real-life corruption using a
similar technique) must first move the broken contents out of the way.
Note also that we now call adjust_shared_perm() twice. We already call
adjust_shared_perm() in stage_tmp_packfiles(), and now call it again in
finalize_object_file(). This is somewhat wasteful, but cleaning up the
existing calls to adjust_shared_perm() is tricky (because sometimes
we're writing to a tmpfile, and sometimes we're writing directly into
the final destination), so let's tolerate some minor waste until we can
more carefully clean up the now-redundant calls.
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 underlying machinery for "git diff-index" has long been made to
expand the sparse index as needed, but the command fully expanded
the sparse index upfront, which now has been taught not to do.
* ds/sparse-diff-index:
diff-index: integrate with the sparse index
Another test for reftable library ported to the unit test framework.
* cp/unit-test-reftable-block:
t-reftable-block: mark unused argv/argc
t-reftable-block: add tests for index blocks
t-reftable-block: add tests for obj blocks
t-reftable-block: add tests for log blocks
t-reftable-block: remove unnecessary variable 'j'
t-reftable-block: use xstrfmt() instead of xstrdup()
t-reftable-block: use block_iter_reset() instead of block_iter_close()
t-reftable-block: use reftable_record_key() instead of strbuf_addstr()
t-reftable-block: use reftable_record_equal() instead of check_str()
t-reftable-block: release used block reader
t: harmonize t-reftable-block.c with coding guidelines
t: move reftable/block_test.c to the unit testing framework
The code in the reftable library has been cleaned up by discarding
unused "generic" interface.
* ps/reftable-drop-generic:
reftable: mark unused parameters in empty iterator functions
reftable/generic: drop interface
t/helper: refactor to not use `struct reftable_table`
t/helper: use `hash_to_hex_algop()` to print hashes
t/helper: inline printing of reftable records
t/helper: inline `reftable_table_print()`
t/helper: inline `reftable_stack_print_directory()`
t/helper: inline `reftable_reader_print_file()`
t/helper: inline `reftable_dump_main()`
reftable/dump: drop unused `compact_stack()`
reftable/generic: move generic iterator code into iterator interface
reftable/iter: drop double-checking logic
reftable/stack: open-code reading refs
reftable/merged: stop using generic tables in the merged table
reftable/merged: rename `reftable_new_merged_table()`
reftable/merged: expose functions to initialize iterators
This is conceptually the same as the cases in df9d638c24 (unit-tests:
ignore unused argc/argv, 2024-08-17), but this unit test was migrated
from the reftable tests in a parallel branch.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
'git for-each-ref' learned a new "--format" atom to find the branch
that the history leading to a given commit "%(is-base:<commit>)" is
likely based on.
* ds/for-each-ref-is-base:
p1500: add is-base performance tests
for-each-ref: add 'is-base' token
commit: add gentle reference lookup method
commit-reach: add get_branch_base_for_tip
"git send-email" learned "--translate-aliases" option that reads
addresses from the standard input and emits the result of applying
aliases on them to the standard output.
* jk/send-email-translate-aliases:
send-email: teach git send-email option to translate aliases
t9001-send-email.sh: update alias list used for pine test
t9001-send-email.sh: fix quoting for mailrc --dump-aliases test
Mark unused parameters as UNUSED to squelch -Wunused warnings.
* jk/mark-unused-parameters:
t-hashmap: stop calling setup() for t_intern() test
scalar: mark unused parameters in dummy function
daemon: mark unused parameters in non-posix fallbacks
setup: mark unused parameter in config callback
test-mergesort: mark unused parameters in trivial callback
t-hashmap: mark unused parameters in callback function
reftable: mark unused parameters in virtual functions
reftable: drop obsolete test function declarations
reftable: ignore unused argc/argv in test functions
unit-tests: ignore unused argc/argv
t/helper: mark more unused argv/argc arguments
oss-fuzz: mark unused argv/argc argument
refs: mark unused parameters in do_for_each_reflog_helper()
refs: mark unused parameters in ref_store fsck callbacks
update-ref: mark more unused parameters in parser callbacks
imap-send: mark unused parameter in ssl_socket_connect() fallback
We created a useless pseudo-merge reachability bitmap that is about
0 commits, and attempted to include commits that are not in packs,
which made no sense. These bugs have been corrected.
* tb/pseudo-merge-bitmap-fixes:
pseudo-merge.c: ensure pseudo-merge groups are closed
pseudo-merge.c: do not generate empty pseudo-merge commits
t/t5333-pseudo-merge-bitmaps.sh: demonstrate empty pseudo-merge groups
pack-bitmap-write.c: select pseudo-merges even for small bitmaps
pack-bitmap: drop redundant args from `bitmap_writer_finish()`
pack-bitmap: drop redundant args from `bitmap_writer_build()`
pack-bitmap: drop redundant args from `bitmap_writer_build_type_index()`
pack-bitmap: initialize `bitmap_writer_init()` with packing_data
A tests for "git maintenance" that were broken on Windows have been
corrected.
* ps/maintenance-detach-fix-more:
builtin/maintenance: fix loose objects task emitting pack hash
t7900: exercise detaching via trace2 regions
t7900: fix flaky test due to leaking background job
Maintenance tasks other than "gc" now properly go background when
"git maintenance" runs them.
* ps/maintenance-detach-fix:
run-command: fix detaching when running auto maintenance
builtin/maintenance: add a `--detach` flag
builtin/gc: add a `--detach` flag
builtin/gc: stop processing log file on signal
builtin/gc: fix leaking config values
builtin/gc: refactor to read config into structure
config: fix constness of out parameter for `git_config_get_expiry()`
The default object hash and ref backend format used to be settable
only with explicit command line option to "git init" and
environment variables, but now they can be configured in the user's
global and system wide configuration.
* ps/hash-and-ref-format-from-config:
setup: make ref storage format configurable via config
setup: make object format configurable via config
setup: merge configuration of repository formats
t0001: delete repositories when object format tests finish
t0001: exercise initialization with ref formats more thoroughly
* cp/unit-test-reftable-readwrite:
t-reftable-readwrite: add test for known error
t-reftable-readwrite: use 'for' in place of infinite 'while' loops
t-reftable-readwrite: use free_names() instead of a for loop
t: move reftable/readwrite_test.c to the unit testing framework
Use of API functions that implicitly depend on the_repository
object in the config subsystem has been rewritten to pass a
repository object through the callchain.
* ps/config-wo-the-repository:
config: hide functions using `the_repository` by default
global: prepare for hiding away repo-less config functions
config: don't depend on `the_repository` with branch conditions
config: don't have setters depend on `the_repository`
config: pass repo to functions that rename or copy sections
config: pass repo to `git_die_config()`
config: pass repo to `git_config_get_expiry_in_days()`
config: pass repo to `git_config_get_expiry()`
config: pass repo to `git_config_get_max_percent_split_change()`
config: pass repo to `git_config_get_split_index()`
config: pass repo to `git_config_get_index_threads()`
config: expose `repo_config_clear()`
config: introduce missing setters that take repo as parameter
path: hide functions using `the_repository` by default
path: stop relying on `the_repository` in `worktree_git_path()`
path: stop relying on `the_repository` when reporting garbage
hooks: remove implicit dependency on `the_repository`
editor: do not rely on `the_repository` for interactive edits
path: expose `do_git_common_path()` as `repo_common_pathv()`
path: expose `do_git_path()` as `repo_git_pathv()`
More leak fixes.
* ps/leakfixes-part-4: (22 commits)
builtin/diff: free symmetric diff members
diff: free state populated via options
builtin/log: fix leak when showing converted blob contents
userdiff: fix leaking memory for configured diff drivers
builtin/format-patch: fix various trivial memory leaks
diff: fix leak when parsing invalid ignore regex option
unpack-trees: clear index when not propagating it
sequencer: release todo list on error paths
merge-ort: unconditionally release attributes index
builtin/fast-export: plug leaking tag names
builtin/fast-export: fix leaking diff options
builtin/fast-import: plug trivial memory leaks
builtin/notes: fix leaking `struct notes_tree` when merging notes
builtin/rebase: fix leaking `commit.gpgsign` value
config: fix leaking comment character config
submodule-config: fix leaking name entry when traversing submodules
read-cache: fix leaking hashfile when writing index fails
bulk-checkin: fix leaking state TODO
object-name: fix leaking symlink paths in object context
object-file: fix memory leak when reading corrupted headers
...
It was recently reported that concurrent reads and writes may cause the
reftable backend to segfault. The root cause of this is that we do not
properly keep track of reftable readers across reloads.
Suppose that you have a reftable iterator and then decide to reload the
stack while iterating through the iterator. When the stack has been
rewritten since we have created the iterator, then we would end up
discarding a subset of readers that may still be in use by the iterator.
The consequence is that we now try to reference deallocated memory,
which of course segfaults.
One way to trigger this is in t5616, where some background maintenance
jobs have been leaking from one test into another. This leads to stack
traces like the following one:
+ git -c protocol.version=0 -C pc1 fetch --filter=blob:limit=29999 --refetch origin
AddressSanitizer:DEADLYSIGNAL
=================================================================
==657994==ERROR: AddressSanitizer: SEGV on unknown address 0x7fa0f0ec6089 (pc 0x55f23e52ddf9 bp
0x7ffe7bfa1700 sp 0x7ffe7bfa1700 T0)
==657994==The signal is caused by a READ memory access.
#0 0x55f23e52ddf9 in get_var_int reftable/record.c:29
#1 0x55f23e53295e in reftable_decode_keylen reftable/record.c:170
#2 0x55f23e532cc0 in reftable_decode_key reftable/record.c:194
#3 0x55f23e54e72e in block_iter_next reftable/block.c:398
#4 0x55f23e5573dc in table_iter_next_in_block reftable/reader.c:240
#5 0x55f23e5573dc in table_iter_next reftable/reader.c:355
#6 0x55f23e5573dc in table_iter_next reftable/reader.c:339
#7 0x55f23e551283 in merged_iter_advance_subiter reftable/merged.c:69
#8 0x55f23e55169e in merged_iter_next_entry reftable/merged.c:123
#9 0x55f23e55169e in merged_iter_next_void reftable/merged.c:172
#10 0x55f23e537625 in reftable_iterator_next_ref reftable/generic.c:175
#11 0x55f23e2cf9c6 in reftable_ref_iterator_advance refs/reftable-backend.c:464
#12 0x55f23e2d996e in ref_iterator_advance refs/iterator.c:13
#13 0x55f23e2d996e in do_for_each_ref_iterator refs/iterator.c:452
#14 0x55f23dca6767 in get_ref_map builtin/fetch.c:623
#15 0x55f23dca6767 in do_fetch builtin/fetch.c:1659
#16 0x55f23dca6767 in fetch_one builtin/fetch.c:2133
#17 0x55f23dca6767 in cmd_fetch builtin/fetch.c:2432
#18 0x55f23dba7764 in run_builtin git.c:484
#19 0x55f23dba7764 in handle_builtin git.c:741
#20 0x55f23dbab61e in run_argv git.c:805
#21 0x55f23dbab61e in cmd_main git.c:1000
#22 0x55f23dba4781 in main common-main.c:64
#23 0x7fa0f063fc89 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
#24 0x7fa0f063fd44 in __libc_start_main_impl ../csu/libc-start.c:360
#25 0x55f23dba6ad0 in _start (git+0xadfad0) (BuildId: 803b2b7f59beb03d7849fb8294a8e2145dd4aa27)
While it is somewhat awkward that the maintenance processes survive
tests in the first place, it is totally expected that reftables should
work alright with concurrent writers. Seemingly they don't.
The only underlying resource that we need to care about in this context
is the reftable reader, which is responsible for reading a single table
from disk. These readers get discarded immediately (unless reused) when
calling `reftable_stack_reload()`, which is wrong. We can only close
them once we know that there are no iterators using them anymore.
Prepare for a fix by converting the reftable readers to be refcounted.
Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rename the `reftable_new_reader()` function to `reftable_reader_new()`
to match our coding guidelines.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The sparse index allows focusing the index data structure on the files
present in the sparse-checkout, leaving only tree entries for
directories not within the sparse-checkout. Each builtin needs a
repository setting to indicate that it has been tested with the sparse
index before Git will allow the index to be loaded into memory in its
sparse form. This is a safety precaution.
There are still some builtins that haven't been integrated due to the
complexity of the integration and the lack of significant use. However,
'git diff-index' was neglected only because of initial data showing low
usage. The diff machinery was already integrated and there is no more
work to be done there but add some tests to be sure 'git diff-index'
behaves as expected.
For this purpose, we can follow the testing pattern used in 51ba65b5c3
(diff: enable and test the sparse index, 2021-12-06). One difference
here is that we only verify that the sparse index case agrees with the
full index case, but do not generate the expected output. The 'git diff'
tests use the '--name-status' option to ease the creation of the
expected output, but that's not an option for 'diff-index'. Since the
underlying diff machinery is the same, a simple comparison is sufficient
to give some coverage.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We do not free negotiation tips in the transport's smart options. Fix
this by freeing them on disconnect.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With the `--atomic` flag, we use a single ref transaction to commit all
ref updates in git-fetch(1). The lifetime of transactions is somewhat
weird: while `ref_transaction_abort()` will free the transaction, a call
to `ref_transaction_commit()` won't. We thus have to manually free the
transaction in the successful case.
Adapt the code to free the transaction in the exit path to plug the
resulting memory leak. As `ref_transaction_abort()` already freed the
transaction for us, we have to unset the transaction when we hit that
code path to not cause a double free.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When expanding remote refs via the refspec in `get_expanded_map()`, we
first copy the remote ref and then override its peer ref with the
expanded name. This may cause a memory leak though in case the peer ref
is already set, as this field is being copied by `copy_ref()`, as well.
Fix the leak by freeing the peer ref before we re-assign the field.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In `match_explicit()`, we try to match a source ref with a destination
ref according to a refspec item. This matching sometimes requires us to
allocate a new source spec so that it looks like we expect. And while we
in some end up assigning this allocated ref as `peer_ref`, which hands
over ownership of it to the caller, in other cases we don't. We neither
free it though, causing a memory leak.
Fix the leak by creating a common exit path where we can easily free the
source ref in case it is allocated and hasn't been handed over to the
caller.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We read a bunch of configs in `use_sideband_colors()` to configure the
colors that Git should use. We never free the strings read from the
config though, causing memory leaks.
Refactor the code to use `git_config_get_string_tmp()` instead, which
does not allocate memory. As we throw the strings away after parsing
them anyway there is no need to use allocated strings.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We never free data associated with the assembled refspec in
git-send-pack(1), causing a memory leak. Fix this.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The transport data for the "git://" protocol contains two OID arrays
that we never free, creating a memory leak. Plug them.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Several of the subcommands of `test-helper read-midx` do not close the
MIDX that they have opened, leading to memory leaks. Fix those.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "--output" switch is an `OPT_FILENAME()` option, which allocates
memory when specified by the user. But while we free the string when
executed without the "--remote" switch, we don't otherwise because we
return via a separate exit path that doesn't know to free it.
Fix this by creating a common exit path.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `-X` switch for git-merge-tree(1) will push each option into a local
`xopts` vector that we then end up parsing. The vector never gets freed
though, causing a memory leak. Plug it.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `format_set_trailers_options()` function is responsible for parsing
a custom pretty format for trailers. It puts the parsed options into a
`struct process_trailer_options` structure, while the allocated memory
required for this will be put into separate caller-provided arguments.
It is thus the caller's responsibility to free the memory not via the
options structure, but via the other parameters.
While we do this alright for the separator and filter keys, we do not
free the memory associated with the key/value separator. Fix this to
plug this memory leak.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When resetting parsed gitattributes, we free the list of convert drivers
parsed from the config. We only free some of the drivers' fields though
and thus have memory leaks.
Fix this by freeing all allocated convert driver fields to plug these
memory leaks.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We populate the `mailinfo` arrays `p_hdr_data` and `s_hdr_data` with
data parsed from the mail headers. These arrays may end up being only
partially populated with gaps in case some of the headers do not parse
properly. This causes memory leaks because `strbuf_list_free()` will
stop iterating once it hits the first `NULL` pointer in the backing
array.
Fix this by open-coding a variant of `strbuf_list_free()` that knows to
iterate through all headers.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `reftable_table` interface provides a generic infrastructure that
can abstract away whether the underlying table is a single table, or a
merged table. This abstraction can make it rather hard to reason about
the code. We didn't ever use it to implement the reftable backend, and
with the preceding patches in this patch series we in fact don't use it
at all anymore. Furthermore, it became somewhat useless with the recent
refactorings that made it possible to seek reftable iterators multiple
times, as these now provide generic access to tables for us. The
interface is thus redundant and only brings unnecessary complexity with
it.
Remove the `struct reftable_table` interface and its associated
functions.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `struct reftable_table` interface in our "reftable" test helper gets
used such that we can easily print either a single table, or a merged
stack. This generic interface is about to go away.
Prepare the code for this change by using merged tables instead. When
printing the stack we've already got one. When using a single table, we
can create a merged table from it to adapt.
This removes the last user of the generic interface.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "reftable" test helper uses a hand-crafted version to convert from a
raw hash to its hex variant. This was done because this code used to be
part of the reftable library, where we do not use most functions from
the Git core.
Now that the code is integrated into the "dump-reftable" helper though,
that limitation went away. Let's thus use `hash_to_hex_algop()` instead.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move printing of reftable records into the "dump-reftable" helper. This
follows the same reasoning as the preceding commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `reftable_table_print()` into the "dump-reftable" helper. This
follows the same reasoning as the preceding commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `reftable_stack_print_directory()` into the "dump-reftable" helper.
This follows the same reasoning as the preceding commit.
Note that this requires us to remove the tests for this functionality in
`reftable/stack_test.c`. The test does not really add much anyway,
because all it verifies is that we do not crash or run into an error,
and it specifically doesn't check the outputted data. Also, as the code
is now part of the test helper, it doesn't make much sense to have a
unit test for it in the first place.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `reftable_reader_print_file()` into the "dump-reftable" helper.
This follows the same reasoning as the preceding commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The printing functionality part of `reftable/dump.c` is really only used
by our "dump-reftable" test helper. It is certainly not generic logic
that is useful to anybody outside of Git, and the format it generates is
quite specific. Still, parts of it are used in our test suite and the
output may be useful to take a peek into reftable stacks, tables and
blocks. So while it does not make sense to expose this as part of the
reftable library, it does make sense to keep it around.
Inline the `reftable_dump_main()` function into the "dump-reftable" test
helper. This clarifies that its format is subject to change and not part
of our public interface. Furthermore, this allows us to iterate on the
implementation in subsequent patches.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The merged table provides access to a reftable stack by merging the
contents of those tables into a virtual table. These subtables are being
tracked via `struct reftable_table`, which is a generic interface for
accessing either a single reftable or a merged reftable. So in theory,
it would be possible for the merged table to merge together other merged
tables.
This is somewhat nonsensical though: we only ever set up a merged table
over normal reftables, and there is no reason to do otherwise. This
generic interface thus makes the code way harder to follow and reason
about than really necessary. The abstraction layer may also have an
impact on performance, even though the extra set of vtable function
calls probably doesn't really matter.
Refactor the merged tables to use a `struct reftable_reader` for each of
the subtables instead, which gives us direct access to the underlying
tables. Adjust names accordingly.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rename `reftable_new_merged_table()` to `reftable_merged_table_new()`
such that the name matches our coding style.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git bundle unbundle" outside a repository triggered a BUG()
unnecessarily, which has been corrected.
* ps/bundle-outside-repo-fix:
bundle: default to SHA1 when reading bundle headers
builtin/bundle: have unbundle check for repo before opening its bundle
The "loose-objects" maintenance tasks executes git-pack-objects(1) to
pack all loose objects into a new packfile. This command ends up
printing the hash of the packfile to stdout though, which clutters the
output of `git maintenance run`.
Fix this issue by disabling stdout of the child process.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In t7900, we exercise the `--detach` logic by checking whether the
command ended up writing anything to its output or not. This supposedly
works because we close stdin, stdout and stderr when daemonizing. But
one, it breaks on platforms where daemonize is a no-op, like Windows.
And second, that git-maintenance(1) outputs anything at all in these
tests is a bug in the first place that we'll fix in a subsequent commit.
Introduce a new trace2 region around the detach which allows us to more
explicitly check whether the detaching logic was executed. This is a
much more direct way to exercise the logic, provides a potentially
useful signal to tracing logs and also works alright on platforms which
do not have the ability to daemonize.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
[jc: dropped a stale in-code comment from a test]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
