When fetching, the client sends "have" commit IDs indicating that the
server does not need to send any object referenced by those commits,
reducing network I/O. When the client is a partial clone, the client
still sends "have"s in this way, even if it does not have every object
referenced by a commit it sent as "have".
If a server omits such an object, it is fine: the client could lazily
fetch that object before this fetch, and it can still do so after.
The issue is when the server sends a thin pack containing an object that
is a REF_DELTA against such a missing object: index-pack fails to fix
the thin pack. When support for lazily fetching missing objects was
added in 8b4c0103a9 ("sha1_file: support lazily fetching missing
objects", 2017-12-08), support in index-pack was turned off in the
belief that it accesses the repo only to do hash collision checks.
However, this is not true: it also needs to access the repo to resolve
REF_DELTA bases.
Support for lazy fetching should still generally be turned off in
index-pack because it is used as part of the lazy fetching process
itself (if not, infinite loops may occur), but we do need to fetch the
REF_DELTA bases. (When fetching REF_DELTA bases, it is unlikely that
those are REF_DELTA themselves, because we do not send "have" when
making such fetches.)
To resolve this, prefetch all missing REF_DELTA bases before attempting
to resolve them. This both ensures that all bases are attempted to be
fetched, and ensures that we make only one request per index-pack
invocation, and not one request per missing object.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When 'git index-pack' is run by 'git clone', its check_objects()
function usually doesn't take long enough to be a concern, but I just
run into a situation where it took about a minute or so: I
inadvertently put some memory pressure on my tiny laptop while cloning
linux.git, and then there was quite a long silence between the
"Resolving deltas" and "Checking connectivity" progress bars.
Show a progress bar during the loop of check_objects() to let the user
know that something is still going on.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The only remaining callers of has_sha1_file() actually have an object_id
already. They can use the "object" variant, rather than dereferencing
the hash themselves.
The code changes here were completely generated by the included
coccinelle patch.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code preparation to replace ulong vars with size_t vars where
appropriate.
* tb/print-size-t-with-uintmax-format:
Upcast size_t variables to uintmax_t when printing
When printing variables which contain a size, today "unsigned long"
is used at many places.
In order to be able to change the type from "unsigned long" into size_t
some day in the future, we need to have a way to print 64 bit variables
on a system that has "unsigned long" defined to be 32 bit, like Win64.
Upcast all those variables into uintmax_t before they are printed.
This is to prepare for a bigger change, when "unsigned long"
will be converted into size_t for variables which may be > 4Gib.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This rounds out the previous three patches, covering the
inequality logic for the "hash" variant of the functions.
As with the previous three, the accompanying code changes
are the mechanical result of applying the coccinelle patch;
see those patches for more discussion.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using the more restrictive oideq() should, in the long run,
give the compiler more opportunities to optimize these
callsites. For now, this conversion should be a complete
noop with respect to the generated code.
The result is also perhaps a little more readable, as it
avoids the "zero is equal" idiom. Since it's so prevalent in
C, I think seasoned programmers tend not to even notice it
anymore, but it can sometimes make for awkward double
negations (e.g., we can drop a few !!oidcmp() instances
here).
This patch was generated almost entirely by the included
coccinelle patch. This mechanical conversion should be
completely safe, because we check explicitly for cases where
oidcmp() is compared to 0, which is what oideq() is doing
under the hood. Note that we don't have to catch "!oidcmp()"
separately; coccinelle's standard isomorphisms make sure the
two are treated equivalently.
I say "almost" because I did hand-edit the coccinelle output
to fix up a few style violations (it mostly keeps the
original formatting, but sometimes unwraps long lines).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A new configuration variable core.usereplacerefs has been added,
primarily to help server installations that want to ignore the
replace mechanism altogether.
* jk/core-use-replace-refs:
add core.usereplacerefs config option
check_replace_refs: rename to read_replace_refs
check_replace_refs: fix outdated comment
This was added as a NEEDSWORK in c3c36d7de2 (replace-object:
check_replace_refs is safe in multi repo environment, 2018-04-11),
waiting for a calmer period. Since doing so now doesn't conflict
with anything in 'pu', it seems as good a time as any.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a repository argument to allow the callers of lookup_blob
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.
As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a repository argument to allow the callers of parse_object_buffer
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.
As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"index-pack --strict" has been taught to make sure that it runs the
final object integrity checks after making the freshly indexed
packfile available to itself.
* jk/index-pack-maint:
index-pack: correct install_packed_git() args
index-pack: handle --strict checks of non-repo packs
prepare_commit_graft: treat non-repository as a noop
The function does not start taking the repository object as a
parameter before v2.18 track. Make the topic mergeable to v2.17
maintenance track by dropping it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 73c3f0f704 (index-pack: check .gitmodules files with
--strict, 2018-05-04) added a call to add_packed_git(), with
the intent that the newly-indexed objects would be available
to the process when we run fsck_finish(). But that's not
what add_packed_git() does. It only allocates the struct,
and you must install_packed_git() on the result. So that
call was effectively doing nothing (except leaking a
struct).
But wait, we passed all of the tests! Does that mean we
don't need the call at all?
For normal cases, no. When we run "index-pack --stdin"
inside a repository, we write the new pack into the object
directory. If fsck_finish() needs to access one of the new
objects, then our initial lookup will fail to find it, but
we'll follow up by running reprepare_packed_git() and
looking again. That logic was meant to handle somebody else
repacking simultaneously, but it ends up working for us
here.
But there is a case that does need this, that we were not
testing. You can run "git index-pack foo.pack" on any file,
even when it is not inside the object directory. Or you may
not even be in a repository at all! This case fails without
doing the proper install_packed_git() call.
We can make this work by adding the install call.
Note that we should be prepared to handle add_packed_git()
failing. We can just silently ignore this case, though. If
fsck_finish() later needs the objects and they're not
available, it will complain itself. And if it doesn't
(because we were able to resolve the whole fsck in the first
pass), then it actually isn't an interesting error at all.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Conversion from uchar[20] to struct object_id continues.
* bc/object-id: (42 commits)
merge-one-file: compute empty blob object ID
add--interactive: compute the empty tree value
Update shell scripts to compute empty tree object ID
sha1_file: only expose empty object constants through git_hash_algo
dir: use the_hash_algo for empty blob object ID
sequencer: use the_hash_algo for empty tree object ID
cache-tree: use is_empty_tree_oid
sha1_file: convert cached object code to struct object_id
builtin/reset: convert use of EMPTY_TREE_SHA1_BIN
builtin/receive-pack: convert one use of EMPTY_TREE_SHA1_HEX
wt-status: convert two uses of EMPTY_TREE_SHA1_HEX
submodule: convert several uses of EMPTY_TREE_SHA1_HEX
sequencer: convert one use of EMPTY_TREE_SHA1_HEX
merge: convert empty tree constant to the_hash_algo
builtin/merge: switch tree functions to use object_id
builtin/am: convert uses of EMPTY_TREE_SHA1_BIN to the_hash_algo
sha1-file: add functions for hex empty tree and blob OIDs
builtin/receive-pack: avoid hard-coded constants for push certs
diff: specify abbreviation size in terms of the_hash_algo
upload-pack: replace use of several hard-coded constants
...
Developer support update, by using BUG() macro instead of die() to
mark codepaths that should not happen more clearly.
* js/use-bug-macro:
BUG_exit_code: fix sparse "symbol not declared" warning
Convert remaining die*(BUG) messages
Replace all die("BUG: ...") calls by BUG() ones
run-command: use BUG() to report bugs, not die()
test-tool: help verifying BUG() code paths
The codepath around object-info API has been taught to take the
repository object (which in turn tells the API which object store
the objects are to be located).
* sb/oid-object-info:
cache.h: allow oid_object_info to handle arbitrary repositories
packfile: add repository argument to cache_or_unpack_entry
packfile: add repository argument to unpack_entry
packfile: add repository argument to read_object
packfile: add repository argument to packed_object_info
packfile: add repository argument to packed_to_object_type
packfile: add repository argument to retry_bad_packed_offset
cache.h: add repository argument to oid_object_info
cache.h: add repository argument to oid_object_info_extended
Now that the internal fsck code has all of the plumbing we
need, we can start checking incoming .gitmodules files.
Naively, it seems like we would just need to add a call to
fsck_finish() after we've processed all of the objects. And
that would be enough to cover the initial test included
here. But there are two extra bits:
1. We currently don't bother calling fsck_object() at all
for blobs, since it has traditionally been a noop. We'd
actually catch these blobs in fsck_finish() at the end,
but it's more efficient to check them when we already
have the object loaded in memory.
2. The second pass done by fsck_finish() needs to access
the objects, but we're actually indexing the pack in
this process. In theory we could give the fsck code a
special callback for accessing the in-pack data, but
it's actually quite tricky:
a. We don't have an internal efficient index mapping
oids to packfile offsets. We only generate it on
the fly as part of writing out the .idx file.
b. We'd still have to reconstruct deltas, which means
we'd basically have to replicate all of the
reading logic in packfile.c.
Instead, let's avoid running fsck_finish() until after
we've written out the .idx file, and then just add it
to our internal packed_git list.
This does mean that the objects are "in the repository"
before we finish our fsck checks. But unpack-objects
already exhibits this same behavior, and it's an
acceptable tradeoff here for the same reason: the
quarantine mechanism means that pushes will be
fully protected.
In addition to a basic push test in t7415, we add a sneaky
pack that reverses the usual object order in the pack,
requiring that index-pack access the tree and blob during
the "finish" step.
This already works for unpack-objects (since it will have
written out loose objects), but we'll check it with this
sneaky pack for good measure.
Signed-off-by: Jeff King <peff@peff.net>
If fsck reports an error, we say only "Error in object".
This isn't quite as bad as it might seem, since the fsck
code would have dumped some errors to stderr already. But it
might help to give a little more context. The earlier output
would not have even mentioned "fsck", and that may be a clue
that the "fsck.*" or "*.fsckObjects" config may be relevant.
Signed-off-by: Jeff King <peff@peff.net>
Precompute and store information necessary for ancestry traversal
in a separate file to optimize graph walking.
* ds/commit-graph:
commit-graph: implement "--append" option
commit-graph: build graph from starting commits
commit-graph: read only from specific pack-indexes
commit: integrate commit graph with commit parsing
commit-graph: close under reachability
commit-graph: add core.commitGraph setting
commit-graph: implement git commit-graph read
commit-graph: implement git-commit-graph write
commit-graph: implement write_commit_graph()
commit-graph: create git-commit-graph builtin
graph: add commit graph design document
commit-graph: add format document
csum-file: refactor finalize_hashfile() method
csum-file: rename hashclose() to finalize_hashfile()
In d8193743e0 (usage.c: add BUG() function, 2017-05-12), a new macro
was introduced to use for reporting bugs instead of die(). It was then
subsequently used to convert one single caller in 588a538ae5
(setup_git_env: convert die("BUG") to BUG(), 2017-05-12).
The cover letter of the patch series containing this patch
(cf 20170513032414.mfrwabt4hovujde2@sigill.intra.peff.net) is not
terribly clear why only one call site was converted, or what the plan
is for other, similar calls to die() to report bugs.
Let's just convert all remaining ones in one fell swoop.
This trick was performed by this invocation:
sed -i 's/die("BUG: /BUG("/g' $(git grep -l 'die("BUG' \*.c)
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code for reading certain pack v2 offsets had a hard-coded 5
representing the number of uint32_t words that we needed to skip over.
Specify this value in terms of a value from the_hash_algo.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a repository argument to allow the callers of oid_object_info
to be more specific about which repository to handle. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.
As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is more consistent with the project style. The majority of Git's
source files use dashes in preference to underscores in their file names.
Signed-off-by: Stefan Beller <sbeller@google.com>
This is more consistent with the project style. The majority of Git's
source files use dashes in preference to underscores in their file names.
Signed-off-by: Stefan Beller <sbeller@google.com>
Refactoring the internal global data structure to make it possible
to open multiple repositories, work with and then close them.
Rerolled by Duy on top of a separate preliminary clean-up topic.
The resulting structure of the topics looked very sensible.
* sb/object-store: (27 commits)
sha1_file: allow sha1_loose_object_info to handle arbitrary repositories
sha1_file: allow map_sha1_file to handle arbitrary repositories
sha1_file: allow map_sha1_file_1 to handle arbitrary repositories
sha1_file: allow open_sha1_file to handle arbitrary repositories
sha1_file: allow stat_sha1_file to handle arbitrary repositories
sha1_file: allow sha1_file_name to handle arbitrary repositories
sha1_file: add repository argument to sha1_loose_object_info
sha1_file: add repository argument to map_sha1_file
sha1_file: add repository argument to map_sha1_file_1
sha1_file: add repository argument to open_sha1_file
sha1_file: add repository argument to stat_sha1_file
sha1_file: add repository argument to sha1_file_name
sha1_file: allow prepare_alt_odb to handle arbitrary repositories
sha1_file: allow link_alt_odb_entries to handle arbitrary repositories
sha1_file: add repository argument to prepare_alt_odb
sha1_file: add repository argument to link_alt_odb_entries
sha1_file: add repository argument to read_info_alternates
sha1_file: add repository argument to link_alt_odb_entry
sha1_file: add raw_object_store argument to alt_odb_usable
pack: move approximate object count to object store
...
Conversion from uchar[20] to struct object_id continues.
* bc/object-id: (36 commits)
convert: convert to struct object_id
sha1_file: introduce a constant for max header length
Convert lookup_replace_object to struct object_id
sha1_file: convert read_sha1_file to struct object_id
sha1_file: convert read_object_with_reference to object_id
tree-walk: convert tree entry functions to object_id
streaming: convert istream internals to struct object_id
tree-walk: convert get_tree_entry_follow_symlinks internals to object_id
builtin/notes: convert static functions to object_id
builtin/fmt-merge-msg: convert remaining code to object_id
sha1_file: convert sha1_object_info* to object_id
Convert remaining callers of sha1_object_info_extended to object_id
packfile: convert unpack_entry to struct object_id
sha1_file: convert retry_bad_packed_offset to struct object_id
sha1_file: convert assert_sha1_type to object_id
builtin/mktree: convert to struct object_id
streaming: convert open_istream to use struct object_id
sha1_file: convert check_sha1_signature to struct object_id
sha1_file: convert read_loose_object to use struct object_id
builtin/index-pack: convert struct ref_delta_entry to object_id
...
The hashclose() method behaves very differently depending on the flags
parameter. In particular, the file descriptor is not always closed.
Perform a simple rename of "hashclose()" to "finalize_hashfile()" in
preparation for functional changes.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a process with multiple repositories open, packfile accessors
should be associated to a single repository and not shared globally.
Move packed_git and packed_git_mru into the_repository and adjust
callers to reflect this.
[nd: while at there, wrap access to these two fields in get_packed_git()
and get_packed_git_mru(). This allows us to lazily initialize these
fields without caller doing that explicitly]
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The index-pack command currently supports the
--check-self-contained-and-connected argument, for internal use only,
that instructs it to only check for broken links and not broken objects.
For partial clones, we need the inverse, so add a --fsck-objects
argument that checks for broken objects and not broken links, also for
internal use only.
This will be used by fetch-pack in a subsequent patch.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert read_sha1_file to take a pointer to struct object_id and rename
it read_object_file. Do the same for read_sha1_file_extended.
Convert one use in grep.c to use the new function without any other code
change, since the pointer being passed is a void pointer that is already
initialized with a pointer to struct object_id. Update the declaration
and definitions of the modified functions, and apply the following
semantic patch to convert the remaining callers:
@@
expression E1, E2, E3;
@@
- read_sha1_file(E1.hash, E2, E3)
+ read_object_file(&E1, E2, E3)
@@
expression E1, E2, E3;
@@
- read_sha1_file(E1->hash, E2, E3)
+ read_object_file(E1, E2, E3)
@@
expression E1, E2, E3, E4;
@@
- read_sha1_file_extended(E1.hash, E2, E3, E4)
+ read_object_file_extended(&E1, E2, E3, E4)
@@
expression E1, E2, E3, E4;
@@
- read_sha1_file_extended(E1->hash, E2, E3, E4)
+ read_object_file_extended(E1, E2, E3, E4)
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert sha1_object_info and sha1_object_info_extended to take pointers
to struct object_id and rename them to use "oid" instead of "sha1" in
their names. Update the declaration and definition and apply the
following semantic patch, plus the standard object_id transforms:
@@
expression E1, E2;
@@
- sha1_object_info(E1.hash, E2)
+ oid_object_info(&E1, E2)
@@
expression E1, E2;
@@
- sha1_object_info(E1->hash, E2)
+ oid_object_info(E1, E2)
@@
expression E1, E2, E3;
@@
- sha1_object_info_extended(E1.hash, E2, E3)
+ oid_object_info_extended(&E1, E2, E3)
@@
expression E1, E2, E3;
@@
- sha1_object_info_extended(E1->hash, E2, E3)
+ oid_object_info_extended(E1, E2, E3)
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert this function to take a pointer to struct object_id and rename
it check_object_signature. Introduce temporaries to convert the return
values of lookup_replace_object and lookup_replace_object_extended into
struct object_id.
The temporaries are needed because in order to convert
lookup_replace_object, open_istream needs to be converted, and
open_istream needs check_sha1_signature to be converted, causing a loop
of dependencies. The temporaries will be removed in a future patch.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert this struct to use a member of type object_id. Convert various
static functions as well.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since the "flags" is shared, it's a good idea to keep track of who
uses what bit. When we need to use more flags in library code, we can
be sure it won't be re-used for another purpose by some caller.
While at there, fix the location of "5" (should be in a different
column than "4" two lines down)
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More abstraction of hash function from the codepath.
* bc/hash-algo:
hash: update obsolete reference to SHA1_HEADER
bulk-checkin: abstract SHA-1 usage
csum-file: abstract uses of SHA-1
csum-file: rename sha1file to hashfile
read-cache: abstract away uses of SHA-1
pack-write: switch various SHA-1 values to abstract forms
pack-check: convert various uses of SHA-1 to abstract forms
fast-import: switch various uses of SHA-1 to the_hash_algo
sha1_file: switch uses of SHA-1 to the_hash_algo
builtin/unpack-objects: switch uses of SHA-1 to the_hash_algo
builtin/index-pack: improve hash function abstraction
hash: create union for hash context allocation
hash: move SHA-1 macros to hash.h
Rename C++ keyword in order to bring the codebase closer to being able
to be compiled with a C++ compiler.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In preparation for implementing narrow/partial clone, the machinery
for checking object connectivity used by gc and fsck has been
taught that a missing object is OK when it is referenced by a
packfile specially marked as coming from trusted repository that
promises to make them available on-demand and lazily.
* jh/fsck-promisors:
gc: do not repack promisor packfiles
rev-list: support termination at promisor objects
sha1_file: support lazily fetching missing objects
introduce fetch-object: fetch one promisor object
index-pack: refactor writing of .keep files
fsck: support promisor objects as CLI argument
fsck: support referenced promisor objects
fsck: support refs pointing to promisor objects
fsck: introduce partialclone extension
extension.partialclone: introduce partial clone extension
Rename struct sha1file to struct hashfile, along with all of its related
functions.
The transformation in this commit was made by global search-and-replace.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert several uses of unsigned char [20] to struct object_id and
convert various hard-coded constants and uses of SHA-1 functions to use
the_hash_algo.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert the declaration and definition of hash_sha1_file to use
struct object_id and adjust all function calls.
Rename this function to hash_object_file.
Signed-off-by: Patryk Obara <patryk.obara@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Let's simplify index-pack option parsing using
skip_to_optional_arg().
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach sha1_file to fetch objects from the remote configured in
extensions.partialclone whenever an object is requested but missing.
The fetching of objects can be suppressed through a global variable.
This is used by fsck and index-pack.
However, by default, such fetching is not suppressed. This is meant as a
temporary measure to ensure that all Git commands work in such a
situation. Future patches will update some commands to either tolerate
missing objects (without fetching them) or be more efficient in fetching
them.
In order to determine the code changes in sha1_file.c necessary, I
investigated the following:
(1) functions in sha1_file.c that take in a hash, without the user
regarding how the object is stored (loose or packed)
(2) functions in packfile.c (because I need to check callers that know
about the loose/packed distinction and operate on both differently,
and ensure that they can handle the concept of objects that are
neither loose nor packed)
(1) is handled by the modification to sha1_object_info_extended().
For (2), I looked at for_each_packed_object and others. For
for_each_packed_object, the callers either already work or are fixed in
this patch:
- reachable - only to find recent objects
- builtin/fsck - already knows about missing objects
- builtin/cat-file - warning message added in this commit
Callers of the other functions do not need to be changed:
- parse_pack_index
- http - indirectly from http_get_info_packs
- find_pack_entry_one
- this searches a single pack that is provided as an argument; the
caller already knows (through other means) that the sought object
is in a specific pack
- find_sha1_pack
- fast-import - appears to be an optimization to not store a file if
it is already in a pack
- http-walker - to search through a struct alt_base
- http-push - to search through remote packs
- has_sha1_pack
- builtin/fsck - already knows about promisor objects
- builtin/count-objects - informational purposes only (check if loose
object is also packed)
- builtin/prune-packed - check if object to be pruned is packed (if
not, don't prune it)
- revision - used to exclude packed objects if requested by user
- diff - just for optimization
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce fetch-object, providing the ability to fetch one object from a
promisor remote.
This uses fetch-pack. To do this, the transport mechanism has been
updated with 2 flags, "from-promisor" to indicate that the resulting
pack comes from a promisor remote (and thus should be annotated as such
by index-pack), and "no-dependents" to indicate that only the objects
themselves need to be fetched (but fetching additional objects is
nevertheless safe).
Whenever "no-dependents" is used, fetch-pack will refrain from using any
object flags, because it is most likely invoked as part of a dynamic
object fetch by another Git command (which may itself use object flags).
An alternative to this is to leave fetch-pack alone, and instead update
the allocation of flags so that fetch-pack's flags never overlap with
any others, but this will end up shrinking the number of flags available
to nearly every other Git command (that is, every Git command that
accesses objects), so the approach in this commit was used instead.
This will be tested in a subsequent commit.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a subsequent commit, index-pack will be taught to write ".promisor"
files which are similar to the ".keep" files it knows how to write.
Refactor the writing of ".keep" files, so that the implementation of
writing ".promisor" files becomes easier.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A common mistake when writing binary search is to allow possible
integer overflow by using the simple average:
mid = (min + max) / 2;
Instead, use the overflow-safe version:
mid = min + (max - min) / 2;
This translation is safe since the operation occurs inside a loop
conditioned on "min < max". The included changes were found using
the following git grep:
git grep '/ *2;' '*.c'
Making this cleanup will prevent future review friction when a new
binary search is contructed based on existing code.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, sha1_file.c and cache.h contain many functions, both related
to and unrelated to packfiles. This makes both files very large and
causes an unclear separation of concerns.
Create a new file, packfile.c, to hold all packfile-related functions
currently in sha1_file.c. It has a corresponding header packfile.h.
In this commit, the pack name-related functions are moved. Subsequent
commits will move the other functions.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
has_sha1_file_with_flags() implements many mechanisms in common with
sha1_object_info_extended(). Make has_sha1_file_with_flags() a
convenience function for sha1_object_info_extended() instead.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A common pattern to free a piece of memory and assign NULL to the
pointer that used to point at it has been replaced with a new
FREE_AND_NULL() macro.
* ab/free-and-null:
*.[ch] refactoring: make use of the FREE_AND_NULL() macro
coccinelle: make use of the "expression" FREE_AND_NULL() rule
coccinelle: add a rule to make "expression" code use FREE_AND_NULL()
coccinelle: make use of the "type" FREE_AND_NULL() rule
coccinelle: add a rule to make "type" code use FREE_AND_NULL()
git-compat-util: add a FREE_AND_NULL() wrapper around free(ptr); ptr = NULL
Fix configuration codepath to pay proper attention to commondir
that is used in multi-worktree situation, and isolate config API
into its own header file.
* bw/config-h:
config: don't implicitly use gitdir or commondir
config: respect commondir
setup: teach discover_git_directory to respect the commondir
config: don't include config.h by default
config: remove git_config_iter
config: create config.h
Apply the result of the just-added coccinelle rule. This manually
excludes a few occurrences, mostly things that resulted in many
FREE_AND_NULL() on one line, that'll be manually fixed in a subsequent
change.
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>
Convert lookup_blob to take a pointer to struct object_id.
The commit was created with manual changes to blob.c and blob.h, plus
the following semantic patch:
@@
expression E1;
@@
- lookup_blob(E1.hash)
+ lookup_blob(&E1)
@@
expression E1;
@@
- lookup_blob(E1->hash)
+ lookup_blob(E1)
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
All but a few callers of lookup_blob have been converted to struct
object_id. Introduce a temporary, which will be removed later, into
parse_object to ease the transition, and convert the remaining callers
so that we can update lookup_blob to take struct object_id *.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert struct pack_idx_entry to use struct object_id by changing the
definition and applying the following semantic patch, plus the standard
object_id transforms:
@@
struct pack_idx_entry E1;
@@
- E1.sha1
+ E1.oid.hash
@@
struct pack_idx_entry *E1;
@@
- E1->sha1
+ E1->oid.hash
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update error handling for codepath that deals with corrupt loose
objects.
* jk/loose-object-info-report-error:
index-pack: detect local corruption in collision check
sha1_loose_object_info: return error for corrupted objects
When we notice that we have a local copy of an incoming
object, we compare the two objects to make sure we haven't
found a collision. Before we get to the actual object
bytes, though, we compare the type and size from
sha1_object_info().
If our local object is corrupted, then the type will be
OBJ_BAD, which obviously will not match the incoming type,
and we'll report "SHA1 COLLISION FOUND" (with capital
letters and everything). This is confusing, as the problem
is not a collision but rather local corruption. We should
report that instead (just like we do if reading the rest of
the object content fails a few lines later).
Note that we _could_ just ignore the error and mark it as a
non-collision. That would let you "git fetch" to replace a
corrupted object. But it's not a very reliable method for
repairing a repository. The earlier want/have negotiation
tries to get the other side to omit objects we already have,
and it would not realize that we are "missing" this
corrupted object. So we're better off complaining loudly
when we see corruption, and letting the user take more
drastic measures to repair (like making a full clone
elsewhere and copying the pack into place).
Note that the test sets transfer.unpackLimit in the
receiving repository so that we use index-pack (which is
what does the collision check). Normally for such a small
push we'd use unpack-objects, which would simply try to
write the loose object, and discard the new one when we see
that there's already an old one.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We'd prefer to avoid unchecked snprintf calls because
truncation can lead to unexpected results.
These are all cases where truncation shouldn't ever happen,
because the input to snprintf is fixed in size. That makes
them candidates for xsnprintf(), but it's simpler still to
just use the heap, and then nobody has to wonder if "100" is
big enough.
We'll use xstrfmt() where possible, and a strbuf when we need
the resulting size or to reuse the same buffer in a loop.
Signed-off-by: Jeff King <peff@peff.net>
The odb_mkstemp() function expects the caller to provide a
fixed buffer to write the resulting tempfile name into. But
it creates the template using snprintf without checking the
return value. This means we could silently truncate the
filename.
In practice, it's unlikely that the truncation would end in
the template-pattern that mkstemp needs to open the file. So
we'd probably end up failing either way, unless the path was
specially crafted.
The simplest fix would be to notice the truncation and die.
However, we can observe that most callers immediately
xstrdup() the result anyway. So instead, let's switch to
using a strbuf, which is easier for them (and isn't a big
deal for the other 2 callers, who can just strbuf_release
when they're done with it).
Note that many of the callers used static buffers, but this
was purely to avoid putting a large buffer on the stack. We
never passed the static buffers out of the function, so
there's no complicated memory handling we need to change.
Signed-off-by: Jeff King <peff@peff.net>
The odb_mkstemp function does not return an error; it dies
on failure instead. But many of its callers compare the
resulting descriptor against -1 and die themselves.
Mostly this is just pointless, but it does raise a question
when looking at the callers: if they show the results of the
"template" buffer after a failure, what's in it? The answer
is: it doesn't matter, because it cannot happen.
So let's make that clear by removing the bogus error checks.
In bitmap_writer_finish(), we can drop the error-handling
code entirely. In the other two cases, it's shared with the
open() in another code path; we can just move the
error-check next to that open() call.
And while we're at it, let's flesh out the function's
docstring a bit to make the error behavior clear.
Signed-off-by: Jeff King <peff@peff.net>
The final() function accepts a NULL value for certain
parameters, and falls back to writing into a reusable "name"
buffer, and then either:
1. For "keep_name", requiring all uses to do "keep_name ?
keep_name : name.buf". This is awkward, and it's easy
to accidentally look at the maybe-NULL keep_name.
2. For "final_index_name" and "final_pack_name", aliasing
those pointers to the "name" buffer. This is easier to
use, but the aliased pointers become invalid after the
buffer is reused (this isn't a bug now, but it's a
potential pitfall).
One way to make this safer would be to introduce an extra
pointer to do the aliasing, and have its lifetime match the
validity of the "name" buffer. But it's still easy to
accidentally use the wrong name (i.e., to use
"final_pack_name" instead of the aliased pointer).
Instead, let's use three separate buffers that will remain
valid through the function. That makes it safe to alias the
pointers and use them consistently. The extra allocations
shouldn't matter, as this function is not performance
sensitive.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In several places we write the name of the pack filename
into a fixed-size buffer using snprintf(), but do not check
the return value. As a result, a very long object directory
could cause us to quietly truncate the pack filename
(potentially leading to a corrupted repository, as a newly
written packfile could be missing its .pack extension).
We can use odb_pack_name() to do this with a strbuf (and
shorten the code, as well).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The odb_pack_keep() function generates the name of a .keep
file and opens it. This has two problems:
1. It requires a fixed-size buffer to create the filename
and doesn't notice when the result is truncated.
2. Of the two callers, one sometimes wants to open a
filename it already has, which makes things awkward (it
has to do so manually, and skips the leading-directory
creation).
Instead, let's have odb_pack_keep() just open the file.
Generating the name isn't hard, and a future patch will
switch callers over to odb_pack_name() anyway.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
You can run "git index-pack path/to/foo.pack" outside of a
repository to generate an index file, or just to verify the
contents. There's no point in doing a collision check, since
we obviously do not have any objects to collide with.
The current code will blindly look in .git/objects based on
the result of setup_git_env(). That effectively gives us the
right answer (since we won't find any objects), but it's a
waste of time, and it conflicts with our desire to
eventually get rid of the "fallback to .git" behavior of
setup_git_env().
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The index-pack builtin is marked as RUN_SETUP_GENTLY,
because it's perfectly fine to index a pack in the
filesystem outside of any repository. However, --stdin mode
will write the result to the object database, which does not
make sense outside of a repository. Doing so creates a bogus
".git" directory with nothing in it except the newly-created
pack and its index.
Instead, let's flag this as an error and abort.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert two more qsort(3) calls to QSORT to reduce code size and for
better safety and consistency.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the semantic patch contrib/coccinelle/qsort.cocci to the code
base, replacing calls of qsort(3) with QSORT. The resulting code is
shorter and supports empty arrays with NULL pointers.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When receiving a pack-file, it can be useful to abort the
`git index-pack`, if the pack-file is too big.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git push" and "git clone" learned to give better progress meters
to the end user who is waiting on the terminal.
* jk/push-progress:
receive-pack: send keepalives during quiet periods
receive-pack: turn on connectivity progress
receive-pack: relay connectivity errors to sideband
receive-pack: turn on index-pack resolving progress
index-pack: add flag for showing delta-resolution progress
clone: use a real progress meter for connectivity check
check_connected: add progress flag
check_connected: relay errors to alternate descriptor
check_everything_connected: use a struct with named options
check_everything_connected: convert to argv_array
rev-list: add optional progress reporting
check_everything_connected: always pass --quiet to rev-list
After a client has sent us the complete pack, we may spend
some time processing the data and running hooks. If the
client asked us to be quiet, receive-pack won't send any
progress data during the index-pack or connectivity-check
steps. And hooks may or may not produce their own progress
output. In these cases, the network connection is totally
silent from both ends.
Git itself doesn't care about this (it will wait forever),
but other parts of the system (e.g., firewalls,
load-balancers, etc) might hang up the connection. So we'd
like to send some sort of keepalive to let the network and
the client side know that we're still alive and processing.
We can use the same trick we did in 05e9515 (upload-pack:
send keepalive packets during pack computation, 2013-09-08).
Namely, we will send an empty sideband data packet every `N`
seconds that we do not relay any stderr data over the
sideband channel. As with 05e9515, this means that we won't
bother sending keepalives when there's actual progress data,
but will kick in when it has been disabled (or if there is a
lull in the progress data).
The concept is simple, but the details are subtle enough
that they need discussing here.
Before the client sends us the pack, we don't want to do any
keepalives. We'll have sent our ref advertisement, and we're
waiting for them to send us the pack (and tell us that they
support sidebands at all).
While we're receiving the pack from the client (or waiting
for it to start), there's no need for keepalives; it's up to
them to keep the connection active by sending data.
Moreover, it would be wrong for us to do so. When we are the
server in the smart-http protocol, we must treat our
connection as half-duplex. So any keepalives we send while
receiving the pack would potentially be buffered by the
webserver. Not only does this make them useless (since they
would not be delivered in a timely manner), but it could
actually cause a deadlock if we fill up the buffer with
keepalives. (It wouldn't be wrong to send keepalives in this
phase for a full-duplex connection like ssh; it's simply
pointless, as it is the client's responsibility to speak).
As soon as we've gotten all of the pack data, then the
client is waiting for us to speak, and we should start
keepalives immediately. From here until the end of the
connection, we send one any time we are not otherwise
sending data.
But there's a catch. Receive-pack doesn't know the moment
we've gotten all the data. It passes the descriptor to
index-pack, who reads all of the data, and then starts
resolving the deltas. We have to communicate that back.
To make this work, we instruct the sideband muxer to enable
keepalives in three phases:
1. In the beginning, not at all.
2. While reading from index-pack, wait for a signal
indicating end-of-input, and then start them.
3. Afterwards, always.
The signal from index-pack in phase 2 has to come over the
stderr channel which the muxer is reading. We can't use an
extra pipe because the portable run-command interface only
gives us stderr and stdout.
Stdout is already used to pass the .keep filename back to
receive-pack. We could also send a signal there, but then we
would find out about it in the main thread. And the
keepalive needs to be done by the async muxer thread (since
it's the one writing sideband data back to the client). And
we can't reliably signal the async thread from the main
thread, because the async code sometimes uses threads and
sometimes uses forked processes.
Therefore the signal must come over the stderr channel,
where it may be interspersed with other random
human-readable messages from index-pack. This patch makes
the signal a single NUL byte. This is easy to parse, should
not appear in any normal stderr output, and we don't have to
worry about any timing issues (like seeing half the signal
bytes in one read(), and half in a subsequent one).
This is a bit ugly, but it's simple to code and should work
reliably.
Another option would be to stop using an async thread for
muxing entirely, and just poll() both stderr and stdout of
index-pack from the main thread. This would work for
index-pack (because we aren't doing anything useful in the
main thread while it runs anyway). But it would make the
connectivity check and the hook muxers much more
complicated, as they need to simultaneously feed the
sub-programs while reading their stderr.
The index-pack phase is the only one that needs this
signaling, so it could simply behave differently than the
other two. That would mean having two separate
implementations of copy_to_sideband (and the keepalive
code), though. And it still doesn't get rid of the
signaling; it just means we can write a nicer message like
"END_OF_INPUT" or something on stdout, since we don't have
to worry about separating it from the stderr cruft.
One final note: this signaling trick is only done with
index-pack, not with unpack-objects. There's no point in
doing it for the latter, because by definition it only kicks
in for a small number of objects, where keepalives are not
as useful (and this conveniently lets us avoid duplicating
the implementation).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The index-pack command has two progress meters: one for
"receiving objects", and one for "resolving deltas". You get
neither by default, or both with "-v".
But for a push through receive-pack, we would want only the
"resolving deltas" phase, _not_ the "receiving objects"
progress. There are two reasons for this.
One is simply that existing clients are already printing
"writing objects" progress at the same time. Arguably
"receiving" from the far end is more useful, because it
tells you what has actually gotten there, as opposed to what
might be stuck in a buffer somewhere between the client and
server. But that would require a protocol extension to tell
clients not to print their progress. Possible, but
complexity for little gain.
The second reason is much more important. In a full-duplex
connection like git-over-ssh, we can print progress while
the pack is incoming, and it will immediately get to the
client. But for a half-duplex connection like git-over-http,
we should not say anything until we have received the full
request. Anything we write is subject to being stuck in a
buffer by the webserver. Worse, we can end up in a deadlock
if that buffer fills up.
So our best bet is to avoid writing anything that isn't a
small fixed size until we've received the full pack.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
unpack_entry_data() receives an off_t value from unpack_raw_entry(),
which could be larger than unsigned long on 32-bit systems with large
file support. Correct the type so truncation does not happen. This
only affects bad object reporting though.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use the right type for offsets in this case, off_t, which makes a
difference on 32-bit systems with large file support, and change
formatting code accordingly.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
On 32-bit systems with large file support, one entry could be larger
than 4GB and overflow "len". Correct it so we can unpack a full entry.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Mark several messages for translation.
* va/i18n-misc-updates:
i18n: unpack-trees: avoid substituting only a verb in sentences
i18n: builtin/pull.c: split strings marked for translation
i18n: builtin/pull.c: mark placeholders for translation
i18n: git-parse-remote.sh: mark strings for translation
i18n: branch: move comment for translators
i18n: branch: unmark string for translation
i18n: builtin/rm.c: remove a comma ',' from string
i18n: unpack-trees: mark strings for translation
i18n: builtin/branch.c: mark option for translation
i18n: index-pack: use plural string instead of normal one
Mark several messages for translation.
* va/i18n-misc-updates:
i18n: unpack-trees: avoid substituting only a verb in sentences
i18n: builtin/pull.c: split strings marked for translation
i18n: builtin/pull.c: mark placeholders for translation
i18n: git-parse-remote.sh: mark strings for translation
i18n: branch: move comment for translators
i18n: branch: unmark string for translation
i18n: builtin/rm.c: remove a comma ',' from string
i18n: unpack-trees: mark strings for translation
i18n: builtin/branch.c: mark option for translation
i18n: index-pack: use plural string instead of normal one
Git could output "completed with 1 local objects", but in this
case using "object" instead of "objects" is the correct form.
Use Q_() instead of _().
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code to read the pack data using the offsets stored in the pack
idx file has been made more carefully check the validity of the
data in the idx.
* jk/pack-idx-corruption-safety:
sha1_file.c: mark strings for translation
use_pack: handle signed off_t overflow
nth_packed_object_offset: bounds-check extended offset
t5313: test bounds-checks of corrupted/malicious pack/idx files
These are automatically named by replacing .pack suffix in the
name of the packfile. Add a small helper to do so, as I'll be
adding another one soonish.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When 592ce208 (index-pack: use strip_suffix to avoid magic numbers,
2014-06-30) refactored the code to derive names of .idx and .keep
files from the name of .pack file, a copy-and-paste typo crept in,
mistakingly attempting to create and store the keep message file in
the .idx file we just created, instead of .keep file.
As we create the .keep file with O_CREAT|O_EXCL, and we do so after
we write the .idx file, we luckily do not clobber the .idx file, but
because we deliberately ignored EEXIST when creating .keep file
(which is justifiable because only the existence of .keep file
matters), nobody noticed this mistake so far.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a pack .idx file has a corrupted offset for an object, we
may try to access an offset in the .idx or .pack file that
is larger than the file's size. For the .pack case, we have
use_pack() to protect us, which realizes the access is out
of bounds. But if the corrupted value asks us to look in the
.idx file's secondary 64-bit offset table, we blindly add it
to the mmap'd index data and access arbitrary memory.
We can fix this with a simple bounds-check compared to the
size we found when we opened the .idx file.
Note that there's similar code in index-pack that is
triggered only during "index-pack --verify". To support
both, we pull the bounds-check into a separate function,
which dies when it sees a corrupted file.
It would be nice if we could return an error, so that the
pack code could try to find a good copy of the object
elsewhere. Currently nth_packed_object_offset doesn't have
any way to return an error, but it could probably use "0" as
a sentinel value (since no object can start there). This is
the minimal fix, and we can improve the resilience later on
top.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If our size computation overflows size_t, we may allocate a
much smaller buffer than we expected and overflow it. It's
probably impossible to trigger an overflow in most of these
sites in practice, but it is easy enough convert their
additions and multiplications into overflow-checking
variants. This may be fixing real bugs, and it makes
auditing the code easier.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Each of these cases can be converted to use ALLOC_ARRAY or
REALLOC_ARRAY, which has two advantages:
1. It automatically checks the array-size multiplication
for overflow.
2. It always uses sizeof(*array) for the element-size,
so that it can never go out of sync with the declared
type of the array.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert all instances of get_object_hash to use an appropriate reference
to the hash member of the oid member of struct object. This provides no
functional change, as it is essentially a macro substitution.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
struct object is one of the major data structures dealing with object
IDs. Convert it to use struct object_id instead of an unsigned char
array. Convert get_object_hash to refer to the new member as well.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
Convert most instances where the sha1 member of struct object is
dereferenced to use get_object_hash. Most instances that are passed to
functions that have versions taking struct object_id, such as
get_sha1_hex/get_oid_hex, or instances that can be trivially converted
to use struct object_id instead, are not converted.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
We generally use 32-byte buffers to format git's "type size"
header fields. These should not generally overflow unless
you can produce some truly gigantic objects (and our types
come from our internal array of constant strings). But it is
a good idea to use xsnprintf to make sure this is the case.
Note that we slightly modify the interface to
write_sha1_file_prepare, which nows uses "hdrlen" as an "in"
parameter as well as an "out" (on the way in it stores the
allocated size of the header, and on the way out it returns
the ultimate size of the header).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 5a688fe4 ("core.sharedrepository = 0mode" should set, not
loosen, 2009-03-25), we kept reminding ourselves:
NEEDSWORK: this should be renamed to finalize_temp_file() as
"moving" is only a part of what it does, when no patch between
master to pu changes the call sites of this function.
without doing anything about it. Let's do so.
The purpose of this function was not to move but to finalize. The
detail of the primarily implementation of finalizing was to link the
temporary file to its final name and then to unlink, which wasn't
even "moving". The alternative implementation did "move" by calling
rename(2), which is a fun tangent.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Allow ignoring fsck errors on specific set of known-to-be-bad
objects, and also tweaking warning level of various kinds of non
critical breakages reported.
* js/fsck-opt:
fsck: support ignoring objects in `git fsck` via fsck.skiplist
fsck: git receive-pack: support excluding objects from fsck'ing
fsck: introduce `git fsck --connectivity-only`
fsck: support demoting errors to warnings
fsck: document the new receive.fsck.<msg-id> options
fsck: allow upgrading fsck warnings to errors
fsck: optionally ignore specific fsck issues completely
fsck: disallow demoting grave fsck errors to warnings
fsck: add a simple test for receive.fsck.<msg-id>
fsck: make fsck_tag() warn-friendly
fsck: handle multiple authors in commits specially
fsck: make fsck_commit() warn-friendly
fsck: make fsck_ident() warn-friendly
fsck: report the ID of the error/warning
fsck (receive-pack): allow demoting errors to warnings
fsck: offer a function to demote fsck errors to warnings
fsck: provide a function to parse fsck message IDs
fsck: introduce identifiers for fsck messages
fsck: introduce fsck options
Disable "have we lost a race with competing repack?" check while
receiving a huge object transfer that runs index-pack.
* jk/index-pack-reduce-recheck:
index-pack: avoid excessive re-reading of pack directory
When c6458e60 (index-pack: kill union delta_base to save memory,
2015-04-18) attempted to reduce the memory footprint of index-pack,
one of the key thing it did was to keep track of ref-deltas and
ofs-deltas separately.
In fix_unresolved_deltas(), however it forgot that it now wants to
look only at ref deltas in one place. The code allocated an array
for nr_unresolved, which is sum of number of ref- and ofs-deltas
minus nr_resolved, which may be larger or smaller than the number
ref-deltas. Depending on nr_resolved, this was either under or over
allocating.
Also, the old code before this change had to use 'i' and 'n' because
some of the things we see in the (old) deltas[] array we scanned
with 'i' would not make it into the sorted_by_pos[] array in the old
world order, but now because you have only ref delta in a separate
ref_deltas[] array, they increment lock&step. We no longer need
separate variables. And most importantly, we shouldn't pass the
nr_unresolved parameter, as this number does not play a role in the
working of this helper function.
Helped-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Disable "have we lost a race with competing repack?" check while
receiving a huge object transfer that runs index-pack.
* jk/index-pack-reduce-recheck:
index-pack: avoid excessive re-reading of pack directory
For example, missing emails in commit and tag objects can be demoted to
mere warnings with
git config receive.fsck.missingemail=warn
The value is actually a comma-separated list.
In case that the same key is listed in multiple receive.fsck.<msg-id>
lines in the config, the latter configuration wins (this can happen for
example when both $HOME/.gitconfig and .git/config contain message type
settings).
As git receive-pack does not actually perform the checks, it hands off
the setting to index-pack or unpack-objects in the form of an optional
argument to the --strict option.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Just like the diff machinery, we are about to introduce more settings,
therefore it makes sense to carry them around as a (pointer to a) struct
containing all of them.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An earlier optimization broke index-pack for a large object
transfer; this fixes it before the breakage hits any released
version.
* nd/slim-index-pack-memory-usage:
index-pack: fix truncation of off_t in comparison
Since 45e8a74 (has_sha1_file: re-check pack directory before
giving up, 2013-08-30), we spend extra effort for
has_sha1_file to give the right answer when somebody else is
repacking. Usually this effort does not matter, because
after finding that the object does not exist, the next step
is usually to die().
However, some code paths make a large number of
has_sha1_file checks which are _not_ expected to return 1.
The collision test in index-pack.c is such a case. On a
local system, this can cause a performance slowdown of
around 5%. But on a system with high-latency system calls
(like NFS), it can be much worse.
This patch introduces a "quick" flag to has_sha1_file which
callers can use when they would prefer high performance at
the cost of false negatives during repacks. There may be
other code paths that can use this, but the index-pack one
is the most obviously critical, so we'll start with
switching that one.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit c6458e6 (index-pack: kill union delta_base to save
memory, 2015-04-18) refactored the comparison functions used
in sorting and binary searching our delta list. The
resulting code does something like:
int cmp_offsets(off_t a, off_t b)
{
return a - b;
}
This works most of the time, but produces nonsensical
results when the difference between the two offsets is
larger than what can be stored in an "int". This can lead to
unresolved deltas if the packsize is larger than 2G (even on
64-bit systems, an int is still typically 32 bits):
$ git clone git://github.com/mozilla/gecko-dev
Cloning into 'gecko-dev'...
remote: Counting objects: 4800161, done.
remote: Compressing objects: 100% (178/178), done.
remote: Total 4800161 (delta 88), reused 0 (delta 0), pack-reused 4799978
Receiving objects: 100% (4800161/4800161), 2.21 GiB | 3.26 MiB/s, done.
Resolving deltas: 99% (3808820/3811944), completed with 0 local objects.
fatal: pack has 3124 unresolved deltas
fatal: index-pack failed
We can fix it by doing direct comparisons between the
offsets and returning constants; the callers only care about
the sign of the comparison, not the magnitude.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Memory usage of "git index-pack" has been trimmed by tens of
per-cent.
* nd/slim-index-pack-memory-usage:
index-pack: kill union delta_base to save memory
index-pack: reduce object_entry size to save memory
Once we know the number of objects in the input pack, we allocate an
array of nr_objects of struct delta_entry. On x86-64, this struct is
32 bytes long. The union delta_base, which is part of struct
delta_entry, provides enough space to store either ofs-delta (8 bytes)
or ref-delta (20 bytes).
Because ofs-delta encoding is more efficient space-wise and more
performant at runtime than ref-delta encoding, Git packers try to use
ofs-delta whenever possible, and it is expected that objects encoded
as ref-delta are minority.
In the best clone case where no ref-delta object is present, we waste
(20-8) * nr_objects bytes because of this union. That's about 38MB out
of 100MB for deltas[] with 3.4M objects, or 38%. deltas[] would be
around 62MB without the waste.
This patch attempts to eliminate that. deltas[] array is split into
two: one for ofs-delta and one for ref-delta. Many functions are also
duplicated because of this split. With this patch, ofs_deltas[] array
takes 51MB. ref_deltas[] should remain unallocated in clone case (0
bytes). This array grows as we see ref-delta. We save about half in
this case, or 25% of total bookkeeping.
The saving is more than the calculation above because some padding in
the old delta_entry struct is removed. ofs_delta_entry is 16 bytes,
including the 4 bytes padding. That's 13MB for padding, but packing
the struct could break platforms that do not support unaligned
access. If someone on 32-bit is really low on memory and only deals
with packs smaller than 2G, using 32-bit off_t would eliminate the
padding and save 27MB on top.
A note about ofs_deltas allocation. We could use ref_deltas memory
allocation strategy for ofs_deltas. But that probably just adds more
overhead on top. ofs-deltas are generally the majority (1/2 to 2/3) in
any pack. Incremental realloc may lead to too many memcpy. And if we
preallocate, say 1/2 or 2/3 of nr_objects initially, the growth rate
of ALLOC_GROW() could make this array larger than nr_objects, wasting
more memory.
Brought-up-by: Matthew Sporleder <msporleder@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Clear the git_zstream variable at the start of git_deflate_init() etc.
so that callers don't have to do that.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
For each object in the input pack, we need one struct object_entry. On
x86-64, this struct is 64 bytes long. Although:
- The 8 bytes for delta_depth and base_object_no are only useful when
show_stat is set. And it's never set unless someone is debugging.
- The three fields hdr_size, type and real_type take 4 bytes each
even though they never use more than 4 bits.
By moving delta_depth and base_object_no out of struct object_entry
and make the other 3 fields one byte long instead of 4, we shrink 25%
of this struct.
On a 3.4M object repo (*) that's about 53MB. The saving is less
impressive compared to index-pack memory use for basic bookkeeping (**),
about 16%.
(*) linux-2.6.git already has 4M objects as of v3.19-rc7 so this is
not an unrealistic number of objects that we have to deal with.
(**) 3.4M * (sizeof(object_entry) + sizeof(delta_entry)) = 311MB
Brought-up-by: Matthew Sporleder <msporleder@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
New tag object format validation added in 2.2 showed garbage
after a tagname it reported in its error message.
* js/fsck-tag-validation:
index-pack: terminate object buffers with NUL
fsck: properly bound "invalid tag name" error message
We have some tricky checks in fsck that rely on a side effect of
require_end_of_header(), and would otherwise easily run outside
non-NUL-terminated buffers. This is a bit brittle, so let's make sure
that only NUL-terminated buffers are passed around to begin with.
Jeff "Peff" King contributed the detailed analysis which call paths are
involved and pointed out that we also have to patch the get_data()
function in unpack-objects.c, which is what Johannes "Dscho" Schindelin
implemented.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Analyzed-by: Jeff King <peff@peff.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
type_cas_lock/unlock() should be defined as no-op for NO_PTHREADS
build, just like all the other locking primitives.
Signed-off-by: Etienne Buira <etienne.buira@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach "git fsck" to inspect the contents of annotated tag objects.
* js/fsck-tag-validation:
Make sure that index-pack --strict checks tag objects
Add regression tests for stricter tag fsck'ing
fsck: check tag objects' headers
Make sure fsck_commit_buffer() does not run out of the buffer
fsck_object(): allow passing object data separately from the object itself
Refactor type_from_string() to allow continuing after detecting an error
When receiving an invalid pack stream that records the same object
twice, multiple threads got confused due to a race. We should
reject or correct such a stream upon receiving, but that will be a
larger change.
* jk/index-pack-threading-races:
index-pack: fix race condition with duplicate bases
When fsck'ing an incoming pack, we need to fsck objects that cannot be
read via read_sha1_file() because they are not local yet (and might even
be rejected if transfer.fsckobjects is set to 'true').
For commits, there is a hack in place: we basically cache commit
objects' buffers anyway, but the same is not true, say, for tag objects.
By refactoring fsck_object() to take the object buffer and size as
optional arguments -- optional, because we still fall back to the
previous method to look at the cached commit objects if the caller
passes NULL -- we prepare the machinery for the upcoming handling of tag
objects.
The assumption that such buffers are inherently NUL terminated is now
wrong, of course, hence we pass the size of the buffer so that we can
add a sanity check later, to prevent running past the end of the buffer.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we are resolving deltas in an indexed pack, we do it by
first selecting a potential base (either one stored in full
in the pack, or one created by resolving another delta), and
then resolving any deltas that use that base. When we
resolve a particular delta, we flip its "real_type" field
from OBJ_{REF,OFS}_DELTA to whatever the real type is.
We assume that traversing the objects this way will visit
each delta only once. This is correct for most packs; we
visit the delta only when we process its base, and each
object (and thus each base) appears only once. However, if a
base object appears multiple times in the pack, we will try
to resolve any deltas based on it once for each instance.
We can detect this case by noting that a delta we are about
to resolve has already had its real_type field flipped, and
we already do so with an assert(). However, if multiple
threads are in use, we may race with another thread on
comparing and flipping the field. We need to synchronize the
access.
The right mechanism for doing this is a compare-and-swap (we
atomically "claim" the delta for our own and find out
whether our claim was successful). We can implement this
in C by using a pthread mutex to protect the operation. This
is not the fastest way of doing a compare-and-swap; many
processors provide instructions for this, and gcc and other
compilers provide builtins to access them. However, some
experiments showed that lock contention does not cause a
significant slowdown here. Adding c-a-s support for many
compilers would increase the maintenance burden (and we
would still end up including the pthread version as a
fallback).
Note that we only need to touch the OBJ_REF_DELTA codepath
here. An OBJ_OFS_DELTA object points to its base using an
offset, and therefore has only one base, even if another
copy of that base object appears in the pack (we do still
touch it briefly because the setting of real_type is
factored out of resolve_data).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use xcalloc() instead of xmalloc() followed by memset() to allocate
and zero out memory because it's shorter and avoids duplicating the
function parameters.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jk/strip-suffix:
prepare_packed_git_one: refactor duplicate-pack check
verify-pack: use strbuf_strip_suffix
strbuf: implement strbuf_strip_suffix
index-pack: use strip_suffix to avoid magic numbers
use strip_suffix instead of ends_with in simple cases
replace has_extension with ends_with
implement ends_with via strip_suffix
add strip_suffix function
sha1_file: replace PATH_MAX buffer with strbuf in prepare_packed_git_one()
A handful of code paths had to read the commit object more than
once when showing header fields that are usually not parsed. The
internal data structure to keep track of the contents of the commit
object has been updated to reduce the need for this double-reading,
and to allow the caller find the length of the object.
* jk/commit-buffer-length:
reuse cached commit buffer when parsing signatures
commit: record buffer length in cache
commit: convert commit->buffer to a slab
commit-slab: provide a static initializer
use get_commit_buffer everywhere
convert logmsg_reencode to get_commit_buffer
use get_commit_buffer to avoid duplicate code
use get_cached_commit_buffer where appropriate
provide helpers to access the commit buffer
provide a helper to set the commit buffer
provide a helper to free commit buffer
sequencer: use logmsg_reencode in get_message
logmsg_reencode: return const buffer
do not create "struct commit" with xcalloc
commit: push commit_index update into alloc_commit_node
alloc: include any-object allocations in alloc_report
replace dangerous uses of strbuf_attach
commit_tree: take a pointer/len pair rather than a const strbuf
Move "commit->buffer" out of the in-core commit object and keep
track of their lengths. Use this to optimize the code paths to
validate GPG signatures in commit objects.
* jk/commit-buffer-length:
reuse cached commit buffer when parsing signatures
commit: record buffer length in cache
commit: convert commit->buffer to a slab
commit-slab: provide a static initializer
use get_commit_buffer everywhere
convert logmsg_reencode to get_commit_buffer
use get_commit_buffer to avoid duplicate code
use get_cached_commit_buffer where appropriate
provide helpers to access the commit buffer
provide a helper to set the commit buffer
provide a helper to free commit buffer
sequencer: use logmsg_reencode in get_message
logmsg_reencode: return const buffer
do not create "struct commit" with xcalloc
commit: push commit_index update into alloc_commit_node
alloc: include any-object allocations in alloc_report
replace dangerous uses of strbuf_attach
commit_tree: take a pointer/len pair rather than a const strbuf
We also switch to using strbufs, which lets us avoid the
potentially dangerous combination of a manual malloc
followed by a strcpy.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These two are almost the same function, with the exception
that has_extension only matches if there is content before
the suffix. So ends_with(".exe", ".exe") is true, but
has_extension would not be.
This distinction does not matter to any of the callers,
though, and we can just replace uses of has_extension with
ends_with. We prefer the "ends_with" name because it is more
generic, and there is nothing about the function that
requires it to be used for file extensions.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git status", even though it is a read-only operation, tries to
update the index with refreshed lstat(2) info to optimize future
accesses to the working tree opportunistically, but this could
race with a "read-write" operation that modify the index while it
is running. Detect such a race and avoid overwriting the index.
* ym/fix-opportunistic-index-update-race:
read-cache.c: verify index file before we opportunistically update it
wrapper.c: add xpread() similar to xread()
The error reporting from "git index-pack" has been improved to
distinguish missing objects from type errors.
* jk/index-pack-report-missing:
index-pack: distinguish missing objects from type errors
We used to disable threaded "git index-pack" on platforms without
thread-safe pread(); use a different workaround for such
platforms to allow threaded "git index-pack".
* nd/index-pack-one-fd-per-thread:
index-pack: work around thread-unsafe pread()
Most callsites which use the commit buffer try to use the
cached version attached to the commit, rather than
re-reading from disk. Unfortunately, that interface provides
only a pointer to the NUL-terminated buffer, with no
indication of the original length.
For the most part, this doesn't matter. People do not put
NULs in their commit messages, and the log code is happy to
treat it all as a NUL-terminated string. However, some code
paths do care. For example, when checking signatures, we
want to be very careful that we verify all the bytes to
avoid malicious trickery.
This patch just adds an optional "size" out-pointer to
get_commit_buffer and friends. The existing callers all pass
NULL (there did not seem to be any obvious sites where we
could avoid an immediate strlen() call, though perhaps with
some further refactoring we could).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This converts two lines into one at each caller. But more
importantly, it abstracts the concept of freeing the buffer,
which will make it easier to change later.
Note that we also need to provide a "detach" mechanism for a
tricky case in index-pack. We are passed a buffer for the
object generated by processing the incoming pack. If we are
not using --strict, we just calculate the sha1 on that
buffer and return, leaving the caller to free it. But if we
are using --strict, we actually attach that buffer to an
object, pass the object to the fsck functions, and then
detach the buffer from the object again (so that the caller
can free it as usual). In this case, we don't want to free
the buffer ourselves, but just make sure it is no longer
associated with the commit.
Note that we are making the assumption here that the
attach/detach process does not impact the buffer at all
(e.g., it is never reallocated or modified). That holds true
now, and we have no plans to change that. However, as we
abstract the commit_buffer code, this dependency becomes
less obvious. So when we detach, let's also make sure that
we get back the same buffer that we gave to the
commit_buffer code.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Enable threaded index-pack on platforms without thread-unsafe
pread() emulation.
* nd/index-pack-one-fd-per-thread:
index-pack: work around thread-unsafe pread()
Read-only operations such as "git status" that internally refreshes
the index write out the refreshed index to the disk to optimize
future accesses to the working tree, but this could race with a
"read-write" operation that modify the index while it is running.
Detect such a race and avoid overwriting the index.
Duy raised a good point that we may need to do the same for the
normal writeout codepath, not just the "opportunistic" update
codepath. While that is true, nobody sane would be running two
simultaneous operations that are clearly write-oriented competing
with each other against the same index file. So in that sense that
can be done as a less urgent follow-up for this topic.
* ym/fix-opportunistic-index-update-race:
read-cache.c: verify index file before we opportunistically update it
wrapper.c: add xpread() similar to xread()
When we fetch a pack that does not contain an object we
expected to receive, we get an error like:
$ git init --bare tmp.git && cd tmp.git
$ git fetch ../parent.git
[...]
error: Could not read 964953ec7bcc0245cb1d0db4095455edd21a2f2e
fatal: Failed to traverse parents of commit b8247b40caf6704fe52736cdece6d6aae87471aa
error: ../parent.git did not send all necessary objects
This comes from the check_everything_connected rev-list. If
we try cloning the same repo (rather than a fetch), we end
up using index-pack's --check-self-contained-and-connected
option instead, which produces output like:
$ git clone --no-local --bare parent.git tmp.git
[...]
fatal: object of unexpected type
fatal: index-pack failed
Not only is the sha1 missing, but it's a misleading message.
There's no type problem, but rather a missing object
problem; we don't notice the difference because we simply
compare OBJ_BAD != OBJ_BLOB. Let's provide a different
message for this case:
$ git clone --no-local --bare parent.git tmp.git
fatal: did not receive expected object 6b00a8c61ed379d5f925a72c1987c9c52129d364
fatal: index-pack failed
While we're at it, let's also improve a true type mismatch
error to look like
fatal: object 6b00a8c61ed379d5f925a72c1987c9c52129d364: expected type blob, got tree
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Multi-threaing of index-pack was disabled with c0f8654
(index-pack: Disable threading on cygwin - 2012-06-26), because
pread() implementations for Cygwin and MSYS were not thread
safe. Recent Cygwin does offer usable pread() and we enabled
multi-threading with 103d530f (Cygwin 1.7 has thread-safe pread,
2013-07-19).
Work around this problem on platforms with a thread-unsafe
pread() emulation by opening one file handle per thread; it
would prevent parallel pread() on different file handles from
stepping on each other.
Also remove NO_THREAD_SAFE_PREAD that was introduced in c0f8654
because it's no longer used anywhere.
This workaround is unconditional, even for platforms with
thread-safe pread() because the overhead is small (a couple file
handles more) and not worth fragmenting the code.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Tested-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is a common mistake to call read(2)/pread(2) and forget to
anticipate that they may return error with EAGAIN/EINTR when the
system call is interrupted.
We have xread() helper to relieve callers of read(2) from having to
worry about it; add xpread() helper to do the same for pread(2).
Update the caller in the builtin/index-pack.c and the mmap emulation
in compat/.
Signed-off-by: Yiannis Marangos <yiannis.marangos@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We feed a string pointer that is potentially NULL to die() when
showing the message. Don't.
Noticed-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The semantics of this flag was changed in commit
e1111cef23 inline lookup_replace_object() calls
but wasn't renamed at the time to minimize code churn. Rename it now,
and add a comment explaining its use.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Leaving only the function definitions and declarations so that any
new topic in flight can still make use of the old functions, replace
existing uses of the prefixcmp() and suffixcmp() with new API
functions.
The change can be recreated by mechanically applying this:
$ git grep -l -e prefixcmp -e suffixcmp -- \*.c |
grep -v strbuf\\.c |
xargs perl -pi -e '
s|!prefixcmp\(|starts_with\(|g;
s|prefixcmp\(|!starts_with\(|g;
s|!suffixcmp\(|ends_with\(|g;
s|suffixcmp\(|!ends_with\(|g;
'
on the result of preparatory changes in this series.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many code paths will free a tree object's buffer and set it
to NULL after finishing with it in order to keep memory
usage down during a traversal. However, out of 8 sites that
do this, only one actually unsets the "parsed" flag back.
Those sites that don't are setting a trap for later users of
the tree object; even after calling parse_tree, the buffer
will remain NULL, causing potential segfaults.
It is not known whether this is triggerable in the current
code. Most commands do not do an in-memory traversal
followed by actually using the objects again. However, it
does not hurt to be safe for future callers.
In most cases, we can abstract this out to a
"free_tree_buffer" helper. However, there are two
exceptions:
1. The fsck code relies on the parsed flag to know that we
were able to parse the object at one point. We can
switch this to using a flag in the "flags" field.
2. The index-pack code sets the buffer to NULL but does
not free it (it is freed by a caller). We should still
unset the parsed flag here, but we cannot use our
helper, as we do not want to free the buffer.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
