When reading bisect refs we read the reference mapping to the "bad" term
into the global `current_bad_oid` variable. This is an allocated string,
but because it is global we never have to free it. This changes though
when `register_ref()` is being called multiple times, at which point
we'll overwrite the previous pointer and thus make it unreachable.
Fix this issue by freeing the previous value. This leak is exposed by
t6030, but plugging it does not make the whole test suite pass.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
bisect: fix leaking string in `handle_bad_merge_base()`
When handling a bad merge base we print an error, which includes the set
of good revisions joined by spaces. This string is allocated, but never
freed.
Fix this memory leak. Note that the local `bad_hex` varible also looks
like a string that we should free. But in fact, `oid_to_hex()` returns
an address to a static variable even though it is declared to return a
non-constant string. The function signature is thus quite misleading and
really should be fixed, but doing so is outside of the scope of this
patch series.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
bisect: fix leaking good/bad terms when reading multipe times
Even though `read_bisect_terms()` is declared as assigning string
constants, it in fact assigns allocated strings to the `read_bad` and
`read_good` out parameters. The only callers of this function assign the
result to global variables and thus don't have to free them in order to
be leak-free. But that changes when executing the function multiple
times because we'd then overwrite the previous value and thus make it
unreachable.
Fix the function signature and free the previous values. This leak is
exposed by t0630, but plugging it does not make the whole test suite
pass.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/blame: fix leaking blame entries with `--incremental`
When passing `--incremental` to git-blame(1) we exit early by jumping to
the `cleanup` label. But some of the cleanups we perform are handled
between the `goto` and its label, and thus we leak the data.
Move the cleanups after the `cleanup` label. While at it, move the logic
to free the scoreboard's `final_buf` into `cleanup_scoreboard()` and
drop its `const` declaration.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
list-objects-filter-options: work around reported leak on error
This one is a little bit more curious. In t6112, we have a test that
exercises the `git rev-list --filter` option with invalid filters. We
execute git-rev-list(1) via `test_must_fail`, which means that we check
for leaks even though Git exits with an error code. This causes the
following leak:
Direct leak of 27 byte(s) in 1 object(s) allocated from:
#0 0x5555555e6946 in realloc.part.0 lsan_interceptors.cpp.o
#1 0x5555558fb4b6 in xrealloc wrapper.c:137:8
#2 0x5555558b6e06 in strbuf_grow strbuf.c:112:2
#3 0x5555558b7550 in strbuf_add strbuf.c:311:2
#4 0x5555557c1a88 in strbuf_addstr strbuf.h:310:2
#5 0x5555557c1d4c in parse_list_objects_filter list-objects-filter-options.c:261:3
#6 0x555555885ead in handle_revision_pseudo_opt revision.c:2899:3
#7 0x555555884e20 in setup_revisions revision.c:3014:11
#8 0x5555556c4b42 in cmd_rev_list builtin/rev-list.c:588:9
#9 0x5555555ec5e3 in run_builtin git.c:483:11
#10 0x5555555eb1e4 in handle_builtin git.c:749:13
#11 0x5555555ec001 in run_argv git.c:819:4
#12 0x5555555eaf94 in cmd_main git.c:954:19
#13 0x5555556fd569 in main common-main.c:64:11
#14 0x7ffff7ca714d in __libc_start_call_main (.../lib/libc.so.6+0x2a14d)
#15 0x7ffff7ca7208 in __libc_start_main@GLIBC_2.2.5 (.../libc.so.6+0x2a208)
#16 0x5555555ad064 in _start (git+0x59064)
This leak is valid, as we call `die()` and do not clean up the memory at
all. But what's curious is that this is the only leak reported, because
we don't clean up any other allocated memory, either, and I have no idea
why the leak sanitizer treats this buffer specially.
In any case, we can work around the leak by shuffling things around a
bit. Instead of calling `gently_parse_list_objects_filter()` and dying
after we have modified the filter spec, we simply do so beforehand. Like
this we don't allocate the buffer in the error case, which makes the
reported leak go away.
It's not pretty, but it manages to make t6112 leak free.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/merge: release output buffer after performing merge
The `obuf` member of `struct merge_options` is used to buffer output in
some cases. In order to not discard its allocated memory we only release
its contents in `merge_finalize()` when we're not currently recursing
into a subtree.
This results in some situations where we seemingly do not release the
buffer reliably. We thus have calls to `strbuf_release()` for this
buffer scattered across the codebase. But we're missing one callsite in
git-merge(1), which causes a memory leak.
We should ideally refactor this interface so that callers don't have to
know about any such internals. But for now, paper over the issue by
adding one more `strbuf_release()` call.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
dir: fix leak when parsing "status.showUntrackedFiles"
We use `repo_config_get_string()` to read "status.showUntrackedFiles"
from the config subsystem. This function allocates the result, but we
never free the result after parsing it.
The value never leaves the scope of the calling function, so refactor it
to instead use `repo_config_get_string_tmp()`, which does not hand over
ownership to the caller.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t/helper: stop re-initialization of `the_repository`
While "common-main.c" already initializes `the_repository` for us, we do
so a second time in the "read-cache" test helper. This causes a memory
leak because the old repository's contents isn't released.
Stop calling `initialize_repository()` to plug this leak.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
While we free the `fsmonitor_dirty` member of `struct index_state`, we
do not free the contents of that EWAH. Do so by using `ewah_free()`
instead of `FREE_AND_NULL()`.
This leak is exposed by t7519, but plugging it alone does not make the
test suite pass.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are several cases where we invalidate untracked cache directory
entries where we do not free the underlying data, but reset the number
of entries. This causes us to leak memory because `free_untracked()`
will not iterate over any potential entries which we still had in the
array.
Fix this issue by freeing old entries. The leak is exposed by t7519, but
plugging it alone does not make the whole test suite pass.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `cnt` variable tracks the number of lines in a patch diff. It can
happen though that there are no newlines, in which case we'd still end
up allocating our array of `sline`s. In fact, we always allocate it with
`cnt + 2` entries: one extra entry for the deletion hunk at the end, and
another entry that we don't seem to ever populate at all but acts as a
kind of sentinel value.
When we loop through the array to clear it at the end of this function
we only loop until `lno < cnt`, and thus we may not end up releasing
whatever the two extra `sline`s contain. While that shouldn't matter for
the sentinel value, it does matter for the extra deletion hunk sline.
Regardless of that, plug this memory leak by releasing both extra
entries, which makes the logic a bit easier to reason about.
While at it, fix the formatting of a local comment, which incidentally
also provides the necessary context for why we overallocate the `sline`
array.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The cleanup string set by the config is leaking when it is being
overridden by an option. Fix this by tracking these via two separate
variables such that we can free the old value.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: fix leaking strbufs when formatting trailers
When formatting trailer lines we iterate through each of the trailers
and munge their respective token/value pairs according to the trailer
options. When formatting a trailer that has its `item->token` pointer
set we perform the munging in two local buffers. In the case where we
figure out that the value is empty and `trim_empty` is set we just skip
over the trailer item. But the buffers are local to the loop and we
don't release their contents, leading to a memory leak.
Plug this leak by lifting the buffers outside of the loop and releasing
them on function return. This fixes the memory leaks, but also optimizes
the loop as we don't have to reallocate the buffers on every single
iteration.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff-lib: fix leaking diffopts in `do_diff_cache()`
In `do_diff_cache()` we initialize a new `rev_info` and then overwrite
its `diffopt` with a user-provided set of options. This can leak memory
because `repo_init_revisions()` may end up allocating memory for the
`diffopt` itself depending on the configuration. And since that field is
overwritten we won't ever free it.
Plug the memory leak by releasing the diffopts before we overwrite them.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In `grep_splice_or()` we search for the next `TRUE` node in our tree of
grep expressions and replace it with the given new expression. But we
don't free the old node, which causes a memory leak. Plug it.
This leak is exposed by t7810, but plugging it alone isn't sufficient to
make the test suite pass.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Fri, 1 Nov 2024 16:53:31 +0000 (12:53 -0400)]
Merge branch 'jk/dumb-http-finalize'
The dumb-http code regressed when the result of re-indexing a pack
yielded an *.idx file that differs in content from the *.idx file it
downloaded from the remote. This has been corrected by no longer
relying on the *.idx file we got from the remote.
* jk/dumb-http-finalize:
packfile: use oidread() instead of hashcpy() to fill object_id
packfile: use object_id in find_pack_entry_one()
packfile: convert find_sha1_pack() to use object_id
http-walker: use object_id instead of bare hash
packfile: warn people away from parse_packed_git()
packfile: drop sha1_pack_index_name()
packfile: drop sha1_pack_name()
packfile: drop has_pack_index()
dumb-http: store downloaded pack idx as tempfile
t5550: count fetches in "previously-fetched .idx" test
midx: avoid duplicate packed_git entries
Taylor Blau [Fri, 1 Nov 2024 16:53:26 +0000 (12:53 -0400)]
Merge branch 'ua/atoi'
Replace various calls to atoi() with strtol_i() and strtoul_ui(), and
add improved error handling.
* ua/atoi:
imap: replace atoi() with strtol_i() for UIDVALIDITY and UIDNEXT parsing
merge: replace atoi() with strtol_i() for marker size validation
daemon: replace atoi() with strtoul_ui() and strtol_i()
Taylor Blau [Fri, 1 Nov 2024 16:53:19 +0000 (12:53 -0400)]
Merge branch 'rj/cygwin-exit'
Treat ECONNABORTED the same as ECONNRESET in 'git credential-cache' to
work around a possible Cygwin regression. This resolves a race condition
caused by changes in Cygwin's handling of socket closures, allowing the
client to exit cleanly when encountering ECONNABORTED.
* rj/cygwin-exit:
credential-cache: treat ECONNABORTED like ECONNRESET
Taylor Blau [Fri, 1 Nov 2024 16:53:16 +0000 (12:53 -0400)]
Merge branch 'ps/platform-compat-fixes'
Various platform compatibility fixes split out of the larger effort
to use Meson as the primary build tool.
* ps/platform-compat-fixes:
t6006: fix prereq handling with `test_format ()`
http: fix build error on FreeBSD
builtin/credential-cache: fix missing parameter for stub function
t7300: work around platform-specific behaviour with long paths on MinGW
t5500, t5601: skip tests which exercise paths with '[::1]' on Cygwin
t3404: work around platform-specific behaviour on macOS 10.15
t1401: make invocation of tar(1) work with Win32-provided one
t/lib-gpg: fix setup of GNUPGHOME in MinGW
t/lib-gitweb: test against the build version of gitweb
t/test-lib: wire up NO_ICONV prerequisite
t/test-lib: fix quoting of TEST_RESULTS_SAN_FILE
In df383b5842 (t/test-lib: wire up NO_ICONV prerequisite, 2024-10-16) we
have introduced a new NO_ICONV prerequisite that makes us skip tests in
case Git is not compiled with support for iconv. This change subtly
broke t6006: while the test suite still passes, some of its tests won't
execute because they run into an error.
./t6006-rev-list-format.sh: line 92: test_expect_%e: command not found
The broken tests use `test_format ()`, and the mentioned commit simply
prepended the new prerequisite to its arguments. But that does not work,
as the function is not aware of prereqs at all and will now treat all of
its arguments incorrectly.
Fix this by making the function aware of prereqs by accepting an
optional fourth argument. Adapt the callsites accordingly.
Reported-by: Josh Steadmon <steadmon@google.com> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 07:08:10 +0000 (03:08 -0400)]
packfile: use oidread() instead of hashcpy() to fill object_id
When chasing a REF_DELTA, we need to pull the raw hash bytes out of the
mmap'd packfile into an object_id struct. We do that with a raw
hashcpy() of the appropriate length (that happens directly now, though
before the previous commit it happened inside find_pack_entry_one(),
also using a hashcpy).
But I think this creates a potentially dangerous situation due to d4d364b2c7 (hash: convert `oidcmp()` and `oideq()` to compare whole
hash, 2024-06-14). When using sha1, we'll have uninitialized bytes in
the latter part of the object_id.hash buffer, which could fool oideq(),
etc.
We should use oidread() instead, which correctly zero-pads the extra
bytes, as of c98d762ed9 (global: ensure that object IDs are always
padded, 2024-06-14).
As far as I can see, this has not been a problem in practice because the
object_id we feed to find_pack_entry_one() is never used with oideq(),
etc. It is being compared to the bytes mmap'd from a pack idx file,
which of course do not have the extra padding bytes themselves. So
there's no bug here, but this just puzzled me while looking at the code.
We should do the more obviously safe thing, both for future-proofing and
to avoid confusing readers.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 07:06:06 +0000 (03:06 -0400)]
packfile: use object_id in find_pack_entry_one()
The main function we use to search a pack index for an object is
find_pack_entry_one(). That function still takes a bare pointer to the
hash, despite the fact that its underlying bsearch_pack() function needs
an object_id struct. And so we end up making an extra copy of the hash
into the struct just to do a lookup.
As it turns out, all callers but one already have such an object_id. So
we can just take a pointer to that struct and use it directly. This
avoids the extra copy and provides a more type-safe interface.
The one exception is get_delta_base() in packfile.c, when we are chasing
a REF_DELTA from inside the pack (and thus we have a pointer directly to
the mmap'd pack memory, not a struct). We can just bump the hashcpy()
from inside find_pack_entry_one() to this one caller that needs it.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 07:05:03 +0000 (03:05 -0400)]
packfile: convert find_sha1_pack() to use object_id
The find_sha1_pack() function has a few problems:
- it's badly named, since it works with any object hash
- it takes the hash as a bare pointer rather than an object_id struct
We can fix both of these easily, as all callers actually have a real
object_id anyway.
I also found the existence of this function somewhat confusing, as it is
about looking in an arbitrary set of linked packed_git structs. It's
good for things like dumb-http which are looking in downloaded remote
packs, and not our local packs. But despite the name, it is not a good
way to find the pack which contains a local object (it skips the use of
the midx, the pack mru list, and so on).
So let's also add an explanatory comment above the declaration that may
point people in the right direction.
I suspect the calls in fast-import.c, which use the packed_git list from
the repository struct, could actually just be using find_pack_entry().
But since we'd need to keep it anyway for dumb-http, I didn't dig
further there. If we eventually drop dumb-http support, then it might be
worth examining them to see if we can get rid of the function entirely.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 07:03:42 +0000 (03:03 -0400)]
http-walker: use object_id instead of bare hash
We long ago switched most code to using object_id structs instead of
bare "unsigned char *" hashes. This gives us more type safety from the
compiler, and generally makes it easier to understand what we expect in
each parameter.
But the dumb-http code has lagged behind. And indeed, the whole "walker"
subsystem interface has the same problem, though http-walker is the only
user left.
So let's update the walker interface to pass object_id structs (which we
already have anyway at all call sites!), and likewise use those within
the http-walker methods that it calls.
This cleans up the dumb-http code a bit, but will also let us fix a few
more commonly used helper functions.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 07:02:22 +0000 (03:02 -0400)]
packfile: warn people away from parse_packed_git()
With a name like parse_packed_git(), you might think it's the right way
to access a local pack index and its associated objects. But not so!
It's a one-off used by the dumb-http code to access pack idx files we've
downloaded from the remote, but whose packs we might not have.
There's only one caller left for this function, and ideally we'd drop it
completely and just inline it there. But that would require exposing
other internals from packfile.[ch], like alloc_packed_git() and
check_packed_git_idx().
So let's leave it be for now, and just warn people that it's probably
not what they're looking for. Perhaps in the long run if we eventually
drop dumb-http support, we can remove the function entirely then.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 07:01:25 +0000 (03:01 -0400)]
packfile: drop sha1_pack_index_name()
Like sha1_pack_name() that we dropped in the previous commit, this
function uses an error-prone static strbuf and the somewhat misleading
name "sha1".
The only caller left is in pack-redundant.c. While this command is
marked for potential removal in our BreakingChanges document, we still
have it for now. But it's simple enough to convert it to use its own
strbuf with the underlying odb_pack_name() function, letting us drop the
otherwise obsolete function.
Note that odb_pack_name() does its own strbuf_reset(), so it's safe to
use directly within a loop like this.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 07:00:55 +0000 (03:00 -0400)]
packfile: drop sha1_pack_name()
The sha1_pack_name() function has a few ugly bits:
- it writes into a static strbuf (and not even a ring buffer of them),
which can lead to subtle invalidation problems
- it uses the term "sha1", but it's really using the_hash_algo, which
could be sha256
There's only one caller of it left. And in fact that caller is better
off using the underlying odb_pack_name() function itself, since it's
just copying the result into its own strbuf anyway.
Converting that caller lets us get rid of this now-obselete function.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 07:00:09 +0000 (03:00 -0400)]
packfile: drop has_pack_index()
The has_pack_index() function has several oddities that may make it
surprising if you are trying to find out if we have a pack with some
$hash:
- it is not looking for a valid pack that we found while searching
object directories. It just looks for any pack-$hash.idx file in the
pack directory.
- it only looks in the local directory, not any alternates
- it takes a bare "unsigned char" hash, which we try to avoid these
days
The only caller it has is in the dumb http code; it wants to know if we
already have the pack idx in question. This can happen if we downloaded
the pack (and generated its index) during a previous fetch.
Before the previous patch ("dumb-http: store downloaded pack idx as
tempfile"), it could also happen if we downloaded the .idx from the
remote but didn't get the matching .pack. But since that patch, we don't
hold on to those .idx files. So there's no need to look for the .idx
file in the filesystem; we can just scan through the packed_git list to
see if we have it.
That lets us simplify the dumb http code a bit, as we know that if we
have the .idx we have the matching .pack already. And it lets us get rid
of this odd function that is unlikely to be needed again.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 06:58:06 +0000 (02:58 -0400)]
dumb-http: store downloaded pack idx as tempfile
This patch fixes a regression in b1b8dfde69 (finalize_object_file():
implement collision check, 2024-09-26) where fetching a v1 pack idx file
over the dumb-http protocol would cause the fetch to fail.
The core of the issue is that dumb-http stores the idx we fetch from the
remote at the same path that will eventually hold the idx we generate
from "index-pack --stdin". The sequence is something like this:
0. We realize we need some object X, which we don't have locally, and
nor does the other side have it as a loose object.
1. We download the list of remote packs from objects/info/packs.
2. For each entry in that file, we download each pack index and store
it locally in .git/objects/pack/pack-$hash.idx (the $hash is not
something we can verify yet and is given to us by the remote).
3. We check each pack index we got to see if it has object X. When we
find a match, we download the matching .pack file from the remote
to a tempfile. We feed that to "index-pack --stdin", which
reindexes the pack, rather than trusting that it has what the other
side claims it does. In most cases, this will end up generating the
exact same (byte-for-byte) pack index which we'll store at the same
pack-$hash.idx path, because the index generation and $hash id are
computed based on what's in the packfile. But:
a. The other side might have used other options to generate the
index. For instance we use index v2 by default, but long ago
it was v1 (and you can still ask for v1 explicitly).
b. The other side might even use a different mechanism to
determine $hash. E.g., long ago it was based on the sorted
list of objects in the packfile, but we switched to using the
pack checksum in 1190a1acf8 (pack-objects: name pack files
after trailer hash, 2013-12-05).
The regression we saw in the real world was (3a). A recent client
fetching from a server with a v1 index downloaded that index, then
complained about trying to overwrite it with its own v2 index. This
collision is otherwise harmless; we know we want to replace the remote
version with our local one, but the collision check doesn't realize
that.
There are a few options to fix it:
- we could teach index-pack a command-line option to ignore only pack
idx collisions, and use it when the dumb-http code invokes
index-pack. This would be an awkward thing to expose users to and
would involve a lot of boilerplate to get the option down to the
collision code.
- we could delete the remote .idx file right before running
index-pack. It should be redundant at that point (since we've just
downloaded the matching pack). But it feels risky to delete
something from our own .git/objects based on what the other side has
said. I'm not entirely positive that a malicious server couldn't lie
about which pack-$hash.idx it has and get us to delete something
precious.
- we can stop co-mingling the downloaded idx files in our local
objects directory. This is a slightly bigger change but I think
fixes the root of the problem more directly.
This patch implements the third option. The big design questions are:
where do we store the downloaded files, and how do we manage their
lifetimes?
There are some additional quirks to the dumb-http system we should
consider. Remember that in step 2 we downloaded every pack index, but in
step 3 we may only download some of the matching packs. What happens to
those other idx files now? They sit in the .git/objects/pack directory,
possibly waiting to be used at a later date. That may save bandwidth for
a subsequent fetch, but it also creates a lot of weird corner cases:
- our local object directory now has semi-untrusted .idx files sitting
around, without their matching .pack
- in case 3b, we noted that we might not generate the same hash as the
other side. In that case even if we download the matching pack,
our index-pack invocation will store it in a different
pack-$hash.idx file. And the unmatched .idx will sit there forever.
- if the server repacks, it may delete the old packs. Now we have
these orphaned .idx files sitting around locally that will never be
used (nor deleted).
- if we repack locally we may delete our local version of the server's
pack index and not realize we have it. So we'll download it again,
even though we have all of the objects it mentions.
I think the right solution here is probably some more complex cache
management system: download the remote .idx files to their own storage
directory, mark them as "seen" when we get their matching pack (to avoid
re-downloading even if we repack), and then delete them when the
server's objects/info/refs no longer mentions them.
But since the dumb http protocol is so ancient and so inferior to the
smart http protocol, I don't think it's worth spending a lot of time
creating such a system. For this patch I'm just downloading the idx
files to .git/objects/tmp_pack_*, and marking them as tempfiles to be
deleted when we exit (and due to the name, any we miss due to a crash,
etc, should eventually be removed by "git gc" runs based on timestamps).
That is slightly worse for one case: if we download an idx but not the
matching pack, we won't retain that idx for subsequent runs. But the
flip side is that we're making other cases better (we never hold on to
useless idx files forever). I suspect that worse case does not even come
up often, since it implies that the packs are generated to match
distinct parts of history (i.e., in practice even in a repo with many
packs you're going to end up grabbing all of those packs to do a clone).
If somebody really cares about that, I think the right path forward is a
managed cache directory as above, and this patch is providing the first
step in that direction anyway (by moving things out of the objects/pack/
directory).
There are two test changes. One demonstrates the broken v1 index case
(it double-checks the resulting clone with fsck to be careful, but prior
to this patch it actually fails at the clone step). The other tweaks the
expectation for a test that covers the "slightly worse" case to
accommodate the extra index download.
The code changes are fairly simple. We stop using finalize_object_file()
to copy the remote's index file into place, and leave it as a tempfile.
We give the tempfile a real ".idx" name, since the packfile code expects
that, and thus we make sure it is out of the usual packs/ directory (so
we'd never mistake it for a real local .idx).
We also have to change parse_pack_index(), which creates a temporary
packed_git to access our index (we need this because all of the pack idx
code assumes we have that struct). It reads the index data from the
tempfile, but prior to this patch would speculatively write the
finalized name into the packed_git struct using the pack-$hash we expect
to use.
I was mildly surprised that this worked at all, since we call
verify_pack_index() on the packed_git which mentions the final name
before moving the file into place! But it works because
parse_pack_index() leaves the mmap-ed data in the struct, so the
lazy-open in verify_pack_index() never triggers, and we read from the
tempfile, ignoring the filename in the struct completely. Hacky, but it
works.
After this patch, parse_pack_index() now uses the index filename we pass
in to derive a matching .pack name. This is OK to change because there
are only two callers, both in the dumb http code (and the other passes
in an existing pack-$hash.idx name, so the derived name is going to be
pack-$hash.pack, which is what we were using anyway).
I'll follow up with some more cleanups in that area, but this patch is
sufficient to fix the regression.
Reported-by: fox <fox.gbr@townlong-yak.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 06:44:17 +0000 (02:44 -0400)]
t5550: count fetches in "previously-fetched .idx" test
We have a test in t5550 that looks at index fetching over dumb http. It
creates two branches, each of which is completely stored in its own
pack, then fetches the branches independently. What should (and does)
happen is that the first fetch grabs both .idx files and one .pack file,
and then the fetch of the second branch re-uses the previously
downloaded .idx files (fetching none) and grabs the now-required .pack
file.
Since the next few patches will be touching this area of the code, let's
beef up the test a little by checking that we're downloading the
expected items at each step.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Jeff King [Fri, 25 Oct 2024 06:43:40 +0000 (02:43 -0400)]
midx: avoid duplicate packed_git entries
When we scan a pack directory to load the idx entries we find into the
packed_git list, we skip any of them that are contained in a midx. We
then load them later lazily if we actually need to access the
corresponding pack, referencing them both from the midx struct and the
packed_git list.
The lazy-load in the midx code checks to see if the midx already
mentions the pack, but doesn't otherwise check the packed_git list. This
makes sense, since we should have added any pack to both lists.
But there's a loophole! If we call close_object_store(), that frees the
midx entirely, but _not_ the packed_git structs, which we must keep
around for Reasons[1]. If we then try to look up more objects, we'll
auto-load the midx again, which won't realize that we've already loaded
those packs, and will create duplicate entries in the packed_git list.
This is possibly inefficient, because it means we may open and map the
pack redundantly. But it can also lead to weird user-visible behavior.
The case I found is in "git repack", which closes and reopens the midx
after repacking and then calls update_server_info(). We end up writing
the duplicate entries into objects/info/packs.
We could obviously de-dup them while writing that file, but it seems
like a violation of more core assumptions that we end up with these
duplicate structs at all.
We can avoid the duplicates reasonably efficiently by checking their
names in the pack_map hash. This annoyingly does require a little more
than a straight hash lookup due to the naming conventions, but it should
only happen when we are about to actually open a pack. I don't think one
extra malloc will be noticeable there.
[1] I'm not entirely sure of all the details, except that we generally
assume the packed_git structs never go away. We noted this
restriction in the comment added by 6f1e9394e2 (object: fix leaking
packfiles when closing object store, 2024-08-08), but it's somewhat
vague. At any rate, if you try freeing the structs in
close_object_store(), you can observe segfaults all over the test
suite. So it might be fixable, but it's not trivial.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Taylor Blau [Fri, 25 Oct 2024 18:02:36 +0000 (14:02 -0400)]
Merge branch 'jc/a-commands-without-the-repo'
Commands that can also work outside Git have learned to take the
repository instance "repo" when we know we are in a repository, and
NULL when we are not, in a parameter. The uses of the_repository
variable in a few of them have been removed using the new calling
convention.
* jc/a-commands-without-the-repo:
archive: remove the_repository global variable
annotate: remove usage of the_repository global
git: pass in repo to builtin based on setup_git_directory_gently
Taylor Blau [Fri, 25 Oct 2024 18:01:21 +0000 (14:01 -0400)]
Merge branch 'ps/ci-gitlab-windows'
Enable Windows-based CI in GitLab.
* ps/ci-gitlab-windows:
gitlab-ci: exercise Git on Windows
gitlab-ci: introduce stages and dependencies
ci: handle Windows-based CI jobs in GitLab CI
ci: create script to set up Git for Windows SDK
t7300: work around platform-specific behaviour with long paths on MinGW
Usman Akinyemi [Thu, 24 Oct 2024 00:24:58 +0000 (00:24 +0000)]
imap: replace atoi() with strtol_i() for UIDVALIDITY and UIDNEXT parsing
Replace unsafe uses of atoi() with strtol_i() to improve error handling
when parsing UIDVALIDITY, UIDNEXT, and APPENDUID in IMAP commands.
Invalid values, such as those with letters, now trigger error messages and
prevent malformed status responses.
I did not add any test for this commit as we do not have any test
for git-imap-send(1) at this point.
Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Usman Akinyemi [Thu, 24 Oct 2024 00:24:57 +0000 (00:24 +0000)]
merge: replace atoi() with strtol_i() for marker size validation
Replace atoi() with strtol_i() for parsing conflict-marker-size to
improve error handling. Invalid values, such as those containing letters
now trigger a clear error message.
Update the test to verify invalid input handling.
Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Usman Akinyemi [Thu, 24 Oct 2024 00:24:56 +0000 (00:24 +0000)]
daemon: replace atoi() with strtoul_ui() and strtol_i()
Replace atoi() with strtoul_ui() for --timeout and --init-timeout
(non-negative integers) and with strtol_i() for --max-connections
(signed integers). This improves error handling and input validation
by detecting invalid values and providing clear error messages.
Update tests to ensure these arguments are properly validated.
Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com>
`git mv a/a.txt a b/` is a nonsense instruction. Instead of failing
gracefully the command trips over itself,[1] leaving behind unfinished
work:
1. first it moves `a/a.txt` to `b/a.txt`; then
2. tries to move `a/`, including `a/a.txt`; then
3. figures out that it’s in a bad state (assertion); and finally
4. aborts.
Now you’re left with a partially-updated index.
The command should instead fail gracefully and make no changes to the
index until it knows that it can complete a sensible action.
For now just add a failing test since this has been known about for
a while.[2]
† 1: Caused by a `pos >= 0` assertion
[2]: https://lore.kernel.org/git/d1f739fe-b28e-451f-9e01-3d2e24a0fe0d@app.fastmail.com/
Helped-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Seyi Kuforiji [Wed, 23 Oct 2024 12:11:12 +0000 (13:11 +0100)]
t9101: ensure no whitespace after redirect
This change updates the script to conform to the coding
standards outlined in the Git project's documentation. According to the
guidelines in Documentation/CodingGuidelines under "Redirection
operators", there should be no whitespace after redirection operators.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Seyi Kuforiji [Sat, 19 Oct 2024 16:34:38 +0000 (17:34 +0100)]
t7011: ensure no whitespace after redirect
This change updates the script to conform to the coding standards
outlined in the Git project's documentation. According to the guidelines
in Documentation/CodingGuidelines under "Redirection operators", there
should be no whitespace after redirection operators.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Taylor Blau [Tue, 22 Oct 2024 18:40:39 +0000 (14:40 -0400)]
Merge branch 'cw/worktree-relative'
An extra worktree attached to a repository points at each other to
allow finding the repository from the worktree and vice versa
possible. Turn this linkage to relative paths.
* cw/worktree-relative:
worktree: add test for path handling in linked worktrees
worktree: link worktrees with relative paths
worktree: refactor infer_backlink() to use *strbuf
worktree: repair copied repository and linked worktrees
Taylor Blau [Tue, 22 Oct 2024 18:40:38 +0000 (14:40 -0400)]
Merge branch 'ps/cache-tree-w-broken-index-entry'
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
Chizoba ODINAKA [Tue, 22 Oct 2024 01:27:01 +0000 (02:27 +0100)]
t6050: avoid pipes with upstream Git commands
In pipes, the exit code of a chain of commands is determined by
the final command. In order not to miss the exit code of a failed
Git command, avoid pipes instead write output of Git commands
into a file.
For better debugging experience, instances of "grep" were changed
to "test_grep". "test_grep" provides more context in case of a
failed "grep".
Signed-off-by: Chizoba ODINAKA <chizobajames21@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com>
René Scharfe [Sun, 20 Oct 2024 11:02:32 +0000 (13:02 +0200)]
grep: disable lookahead on error
regexec(3) can fail. E.g. on macOS it fails if it is used with an UTF-8
locale to match a valid regex against a buffer containing invalid UTF-8
characters.
git grep has two ways to search for matches in a file: Either it splits
its contents into lines and matches them separately, or it matches the
whole content and figures out line boundaries later. The latter is done
by look_ahead() and it's quicker in the common case where most files
don't contain a match.
Fall back to line-by-line matching if look_ahead() encounters an
regexec(3) error by propagating errors out of patmatch() and bailing out
of look_ahead() if there is one. This way we at least can find matches
in lines that contain only valid characters. That matches the behavior
of grep(1) on macOS.
pcre2match() dies if pcre2_jit_match() or pcre2_match() fail, but since
we use the flag PCRE2_MATCH_INVALID_UTF it handles invalid UTF-8
characters gracefully. So implement the fall-back only for regexec(3)
and leave the PCRE2 matching unchanged.
Reported-by: David Gstir <david@sigma-star.at> Signed-off-by: René Scharfe <l.s.r@web.de> Tested-by: David Gstir <david@sigma-star.at> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Add a paragraph which just emphasizes that the command without any
options does not support refs in the final arguments. This is clear
already from the names `<new-oid>` and `<old-oid>` but the right balance
of redundancy makes documentation robust against stray interpretation.
This is also a good place to mention why `--stdin` has those `symref-*`
commands.
This paragraph interrupts the flow of the section by going into detail
about what a symbolic ref file is and how it is implemented. It is not
clear what the purpose is since symbolic refs were already mentioned
prior (“possibly dereferencing the symbolic refs”). Worse, it can
confuse the reader about what argument can be a symbolic ref since it
just says “it” and not which of the parameters; in turn the reader can
be lead to try `<new-oid>` and then get a confusing error since
update-ref will just say that it is not a valid SHA1.
gitglossary(7) already documents what a symref is, concretely, and quite
well at that.
Documentation/git-update-ref.txt: demote symlink to last section
Move the discussion of file system symbolic links to a new “Notes”
section (inspired by the one in git-symbolic-ref(1)) since this is
mostly of historical note at this point, not something that is needed in
the main section of the documentation.
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Remove paragraphs which explain that using this command is safer than
echoing the branch name into `HEAD`.
Evoking the echo strategy is wrong now under the reftable backend since
this file does not exist. And the ref file backend majority user base
use porcelain commands to manage `HEAD` unless they are intentionally
poking at the implementation.
Maybe this warning was relevant for the usage patterns when it was
added[1] but now it just takes up space.
ref-filter: format iteratively with lexicographic refname sorting
In bd98f9774e (ref-filter.c: filter & format refs in the same callback,
2023-11-14), we have introduced logic into the ref-filter subsystem that
determines whether or not we can output references iteratively instead
of first collecting all references, post-processing them and printing
them once done. This has the advantage that we don't have to store all
refs in memory and, when used with e.g. `--count=1`, that we don't have
to read all refs in the first place.
One restriction we have in place for that is that caller must not ask
for sorted refs, because there is no way to sort the refs without first
reading them all into an array. So the benefits can only be reaped when
explicitly asking for output not to be sorted.
But there is one exception here where we _can_ get away with sorting
refs while streaming: ref backends sort references returned by their
iterators in lexicographic order. So if the following conditions are all
true we can do iterative streaming:
- There must be at most a single sorting specification, as otherwise
we're not using plain lexicographic ordering.
- The sorting specification must use the "refname".
- The sorting specification must not be using any flags, like
case-insensitive sorting.
Now the resulting logic does feel quite fragile overall, which makes me
a bit uneasy. But after thinking about this for a while I couldn't find
any obvious gaps in my reasoning. Furthermore, given that lexicographic
sorting order is the default in git-for-each-ref(1), this is likely to
benefit a whole lot of usecases out there.
The following benchmark executes git-for-each-ref(1) in a crafted repo
with 1 million references:
Benchmark 1: git for-each-ref (revision = HEAD~)
Time (mean ± σ): 6.756 s ± 0.014 s [User: 3.004 s, System: 3.541 s]
Range (min … max): 6.738 s … 6.784 s 10 runs
Benchmark 2: git for-each-ref (revision = HEAD)
Time (mean ± σ): 6.479 s ± 0.017 s [User: 2.858 s, System: 3.422 s]
Range (min … max): 6.450 s … 6.519 s 10 runs
Summary
git for-each-ref (revision = HEAD)
1.04 ± 0.00 times faster than git for-each-ref (revision = HEAD~)
The change results in a slight performance improvement, but nothing that
would really stand out. Something that cannot be seen in the benchmark
though is peak memory usage, which went from 404.5MB to 68.96kB.
A more interesting benchmark is printing a single referenence with
`--count=1`:
Benchmark 1: git for-each-ref --count=1 (revision = HEAD~)
Time (mean ± σ): 6.655 s ± 0.018 s [User: 2.865 s, System: 3.576 s]
Range (min … max): 6.630 s … 6.680 s 10 runs
Benchmark 2: git for-each-ref --count=1 (revision = HEAD)
Time (mean ± σ): 8.6 ms ± 1.3 ms [User: 2.3 ms, System: 6.1 ms]
Range (min … max): 6.7 ms … 14.4 ms 266 runs
Summary
git git for-each-ref --count=1 (revision = HEAD)
770.58 ± 116.19 times faster than git for-each-ref --count=1 (revision = HEAD~)
Whereas we scaled with the number of references before, we now print the
first reference and exit immediately, which provides a massive win.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Taylor Blau <me@ttaylorr.com>
notes: teach the -e option to edit messages in editor
Notes can be added to a commit using:
- "-m" to provide a message on the command line.
- -C to copy a note from a blob object.
- -F to read the note from a file.
When these options are used, Git does not open an editor,
it simply takes the content provided via these options and
attaches it to the commit as a note.
Improve flexibility to fine-tune the note before finalizing it
by allowing the messages to be prefilled in the editor and edited
after the messages have been provided through -[mF].
Signed-off-by: Abraham Samuel Adekunle <abrahamadekunle50@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Ramsay Jones [Fri, 18 Oct 2024 05:29:52 +0000 (01:29 -0400)]
credential-cache: treat ECONNABORTED like ECONNRESET
On Cygwin, t0301 fails because "git credential-cache exit" returns a
non-zero exit code. What's supposed to happen here is:
1. The client (the "credential-cache" invocation above) connects to a
previously-spawned credential-cache--daemon.
2. The client sends an "exit" command to the daemon.
3. The daemon unlinks the socket and then exits, closing the
descriptor back to the client.
4. The client sees EOF on the descriptor and exits successfully.
That works on most platforms, and even _used_ to work on Cygwin. But
that changed in Cygwin's ef95c03522 (Cygwin: select: Fix FD_CLOSE
handling, 2021-04-06). After that commit, the client sees a read error
with errno set to ECONNABORTED, and it reports the error and dies.
It's not entirely clear if this is a Cygwin bug. It seems that calling
fclose() on the filehandles pointing to the sockets is sufficient to
avoid this error return, even though exiting should in general look the
same from the client's perspective.
However, we can't just call fclose() here. It's important in step 3
above to unlink the socket before closing the descriptor to avoid the
race mentioned by 7d5e9c9849 (credential-cache--daemon: clarify "exit"
action semantics, 2016-03-18). The client will exit as soon as it sees
the descriptor close, and the daemon may or may not have actually
unlinked the socket by then. That makes test code like this:
before we exit(). Or by replacing the exit() with a return up the stack,
in which case the fclose() happens as we unwind. But in that case we'd
still need to call delete_tempfile() here to avoid the race.
But simpler still is that we can notice that we already special-case
ECONNRESET on the client side, courtesy of 1f180e5eb9 (credential-cache:
interpret an ECONNRESET as an EOF, 2017-07-27). We can just do the same
thing here (I suspect that prior to the Cygwin commit that introduced
this problem, we were really just seeing ECONNRESET instead of
ECONNABORTED, so the "new" problem is just the switch of the errno
values).