Now that all code paths correctly set the hash algorithm member of
struct object_id, write an object's hex representation using the hash
algorithm member embedded in it.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are numerous places in the codebase where we assume we can
initialize data by zeroing all its bytes. However, when we do that with
a struct object_id, it leaves the structure with a zero value for the
algorithm, which is invalid.
We could forbid this pattern and require that all struct object_id
instances be initialized using oidclr, but this seems burdensome and
it's unnatural to most C programmers. Instead, if the algorithm is
zero, assume we wanted to use the default hash algorithm instead.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We use struct object_id for the names of objects. It isn't intended to
be used for other hash values that don't name objects such as the pack
hash.
Because struct object_id will soon need to have its algorithm member
set, using it in this code path would mean that we didn't set that
member, only the hash member, which would result in a crash. For both
of these reasons, switch to using an unsigned char array of size
GIT_MAX_RAWSZ.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The idea behind struct object_id is that it is supposed to represent the
identifier of a standard Git object or a special pseudo-object like the
all-zeros object ID. In this case, we have file hashes, which, while
similar, are distinct from the identifiers of objects.
Switch these code paths to use an unsigned char array. This is both
more logically consistent and it means that we need not set the
algorithm identifier for the struct object_id.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In most cases, when we load the hash of an object into a struct
object_id, we load it using one of the oid* or *_oid_hex functions.
However, for git show-index, we read it in directly using fread. As a
consequence, set the algorithm correctly so the objects can be used
correctly both now and in the future.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Up until recently, object IDs did not have an algorithm member, only a
hash. Consequently, it was possible to share one null (all-zeros)
object ID among all hash algorithms. Now that we're going to be
handling objects from multiple hash algorithms, it's important to make
sure that all object IDs have a correct algorithm field.
Introduce a per-algorithm null OID, and add it to struct hash_algo.
Introduce a wrapper function as well, and use it everywhere we used to
use the null_oid constant.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that struct object_id has an algorithm field, we should populate it.
This will allow us to handle object IDs in any supported algorithm and
distinguish between them. Ensure that the field is written whenever we
write an object ID by storing it explicitly every time we write an
object. Set values for the empty blob and tree values as well.
In addition, use the algorithm field to compare object IDs. Note that
because we zero-initialize struct object_id in many places throughout
the codebase, we default to the default algorithm in cases where the
algorithm field is zero rather than explicitly initialize all of those
locations.
This leads to a branch on every comparison, but the alternative is to
compare the entire buffer each time and padding the buffer for SHA-1.
That alternative ranges up to 3.9% worse than this approach on the perf
t0001, t1450, and t1451.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that we need our instances of struct object_id to be zero padded, we
can no longer cast unsigned char buffers to be pointers to struct
object_id. This file reads data out of the pack objects and then
inserts it directly into a linked list item which is a pointer to struct
object_id. Instead, let's have the linked list item hold its own struct
object_id and copy the data into it.
In addition, since these are not really pointers to struct object_id,
stop passing them around as such, and call them what they really are:
pointers to unsigned char.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we're hashing a value which is going to be an object ID, we want to
zero-pad that value if necessary. To do so, use the final_oid_fn
instead of the final_fn anytime we're going to create an object ID to
ensure we perform this operation.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To avoid the penalty of having to branch in hash comparison functions,
we'll want to always compare the full hash member in a struct object_id,
which will require that SHA-1 object IDs be zero-padded. To do so, add
a function which finalizes a hash context and writes it into an object
ID that performs this padding.
Move the definition of struct object_id and the constant definitions
higher up so we they are available for us to use.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In most places in the codebase, we use oidread to properly read an
object ID into a struct object_id. However, in the HTTP code, we end up
needing to parse a loose object path with a slash in it, so we can't do
that. Let's instead explicitly set the algorithm in this function so we
can rely on it in the future.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the future, we'll want oidread to automatically set the hash
algorithm member for an object ID we read into it, so ensure we use
oidread instead of hashcpy everywhere we're copying a hash value into a
struct object_id.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that we're working with multiple hash algorithms in the same repo,
it's best if we label each object ID with its algorithm so we can
determine how to format a given object ID. Add a member called algo to
struct object_id.
Performance testing on object ID-heavy workloads doesn't reveal a clear
change in performance. Out of performance tests t0001 and t1450, there
are slight variations in performance both up and down, but all
measurements are within the margin of error.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git daemon" has been tightened against systems that take backslash
as directory separator.
* rs/daemon-sanitize-dir-sep:
daemon: sanitize all directory separators
The ort merge backend has been optimized by skipping irrelevant
renames.
* en/ort-perf-batch-9:
diffcore-rename: avoid doing basename comparisons for irrelevant sources
merge-ort: skip rename detection entirely if possible
merge-ort: use relevant_sources to filter possible rename sources
merge-ort: precompute whether directory rename detection is needed
merge-ort: introduce wrappers for alternate tree traversal
merge-ort: add data structures for an alternate tree traversal
merge-ort: precompute subset of sources for which we need rename detection
diffcore-rename: enable filtering possible rename sources
"git cherry-pick/revert" with or without "--[no-]edit" did not spawn
the editor as expected (e.g. "revert --no-edit" after a conflict
still asked to edit the message), which has been corrected.
* en/sequencer-edit-upon-conflict-fix:
sequencer: fix edit handling for cherry-pick and revert messages
"git clone --reject-shallow" option fails the clone as soon as we
notice that we are cloning from a shallow repository.
* ll/clone-reject-shallow:
builtin/clone.c: add --reject-shallow option
An on-disk reverse-index to map the in-pack location of an object
back to its object name across multiple packfiles is introduced.
* tb/reverse-midx:
midx.c: improve cache locality in midx_pack_order_cmp()
pack-revindex: write multi-pack reverse indexes
pack-write.c: extract 'write_rev_file_order'
pack-revindex: read multi-pack reverse indexes
Documentation/technical: describe multi-pack reverse indexes
midx: make some functions non-static
midx: keep track of the checksum
midx: don't free midx_name early
midx: allow marking a pack as preferred
t/helper/test-read-midx.c: add '--show-objects'
builtin/multi-pack-index.c: display usage on unrecognized command
builtin/multi-pack-index.c: don't enter bogus cmd_mode
builtin/multi-pack-index.c: split sub-commands
builtin/multi-pack-index.c: define common usage with a macro
builtin/multi-pack-index.c: don't handle 'progress' separately
builtin/multi-pack-index.c: inline 'flags' with options
Fsck API clean-up.
* ab/fsck-api-cleanup:
fetch-pack: use new fsck API to printing dangling submodules
fetch-pack: use file-scope static struct for fsck_options
fetch-pack: don't needlessly copy fsck_options
fsck.c: move gitmodules_{found,done} into fsck_options
fsck.c: add an fsck_set_msg_type() API that takes enums
fsck.c: pass along the fsck_msg_id in the fsck_error callback
fsck.[ch]: move FOREACH_FSCK_MSG_ID & fsck_msg_id from *.c to *.h
fsck.c: give "FOREACH_MSG_ID" a more specific name
fsck.c: undefine temporary STR macro after use
fsck.c: call parse_msg_type() early in fsck_set_msg_type()
fsck.h: re-order and re-assign "enum fsck_msg_type"
fsck.h: move FSCK_{FATAL,INFO,ERROR,WARN,IGNORE} into an enum
fsck.c: refactor fsck_msg_type() to limit scope of "int msg_type"
fsck.c: rename remaining fsck_msg_id "id" to "msg_id"
fsck.c: remove (mostly) redundant append_msg_id() function
fsck.c: rename variables in fsck_set_msg_type() for less confusion
fsck.h: use "enum object_type" instead of "int"
fsck.h: use designed initializers for FSCK_OPTIONS_{DEFAULT,STRICT}
fsck.c: refactor and rename common config callback
A few option description strings started with capital letters,
which were corrected.
* cc/downcase-opt-help:
column, range-diff: downcase option description
SECURITY.md that is facing individual contributors and end users
has been introduced. Also a procedure to follow when preparing
embargoed releases has been spelled out.
* js/security-md:
Document how we do embargoed releases
SECURITY: describe how to report vulnerabilities
Optimize "rev-list --use-bitmap-index --objects" corner case that
uses negative tags as the stopping points.
* ps/pack-bitmap-optim:
pack-bitmap: avoid traversal of objects referenced by uninteresting tag
"git commit" learned "--trailer <key>[=<value>]" option; together
with the interpret-trailers command, this will make it easier to
support custom trailers.
* zh/commit-trailer:
commit: add --trailer option
The hashwrite() API uses a buffering mechanism to avoid calling
write(2) too frequently. This logic has been refactored to be
easier to understand.
* ds/clarify-hashwrite:
csum-file: make hashwrite() more readable
Plug or annotate remaining leaks that trigger while running the
very basic set of tests.
* ah/plugleaks:
transport: also free remote_refs in transport_disconnect()
parse-options: don't leak alias help messages
parse-options: convert bitfield values to use binary shift
init-db: silence template_dir leak when converting to absolute path
init: remove git_init_db_config() while fixing leaks
worktree: fix leak in dwim_branch()
clone: free or UNLEAK further pointers when finished
reset: free instead of leaking unneeded ref
symbolic-ref: don't leak shortened refname in check_symref()
"git format-patch -v<n>" learned to allow a reroll count that is
not an integer.
* zh/format-patch-fractional-reroll-count:
format-patch: allow a non-integral version numbers
A simple IPC interface gets introduced to build services like
fsmonitor on top.
* jh/simple-ipc:
t0052: add simple-ipc tests and t/helper/test-simple-ipc tool
simple-ipc: add Unix domain socket implementation
unix-stream-server: create unix domain socket under lock
unix-socket: disallow chdir() when creating unix domain sockets
unix-socket: add backlog size option to unix_stream_listen()
unix-socket: eliminate static unix_stream_socket() helper function
simple-ipc: add win32 implementation
simple-ipc: design documentation for new IPC mechanism
pkt-line: add options argument to read_packetized_to_strbuf()
pkt-line: add PACKET_READ_GENTLE_ON_READ_ERROR option
pkt-line: do not issue flush packets in write_packetized_*()
pkt-line: eliminate the need for static buffer in packet_write_gently()
Preparatory API changes for parallel checkout.
* mt/parallel-checkout-part-1:
entry: add checkout_entry_ca() taking preloaded conv_attrs
entry: move conv_attrs lookup up to checkout_entry()
entry: extract update_ce_after_write() from write_entry()
entry: make fstat_output() and read_blob_entry() public
entry: extract a header file for entry.c functions
convert: add classification for conv_attrs struct
convert: add get_stream_filter_ca() variant
convert: add [async_]convert_to_working_tree_ca() variants
convert: make convert_attrs() and convert structs public
Don't show the very verbose $(FIND_SOURCE_FILES) command on every
"make TAGS" invocation.
Let's use "generate into temporary and rename to the final file,
after seeing the command that generated the output finished
successfully" pattern, to avoid leaving a file with an incorrect
output generated by a failed command.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There is a lot of pointer dereferencing in the pre-image version of
'midx_pack_order_cmp()', which this patch gets rid of.
Instead of comparing the pack preferred-ness and then the pack id, both
of these checks are done at the same time by using the high-order bit of
the pack id to represent whether it's preferred. Then the pack id and
offset are compared as usual.
This produces the same result so long as there are less than 2^31 packs,
which seems like a likely assumption to make in practice.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Implement the writing half of multi-pack reverse indexes. This is
nothing more than the format describe a few patches ago, with a new set
of helper functions that will be used to clear out stale .rev files
corresponding to old MIDXs.
Unfortunately, a very similar comparison function as the one implemented
recently in pack-revindex.c is reimplemented here, this time accepting a
MIDX-internal type. An effort to DRY these up would create more
indirection and overhead than is necessary, so it isn't pursued here.
Currently, there are no callers which pass the MIDX_WRITE_REV_INDEX
flag, meaning that this is all dead code. But, that won't be the case
for long, since subsequent patches will introduce the multi-pack bitmap,
which will begin passing this field.
(In midx.c:write_midx_internal(), the two adjacent if statements share a
conditional, but are written separately since the first one will
eventually also handle the MIDX_WRITE_BITMAP flag, which does not yet
exist.)
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Existing callers provide the reverse index code with an array of 'struct
pack_idx_entry *'s, which is then sorted by pack order (comparing the
offsets of each object within the pack).
Prepare for the multi-pack index to write a .rev file by providing a way
to write the reverse index without an array of pack_idx_entry (which the
MIDX code does not have).
Instead, callers can invoke 'write_rev_index_positions()', which takes
an array of uint32_t's. The ith entry in this array specifies the ith
object's (in index order) position within the pack (in pack order).
Expose this new function for use in a later patch, and rewrite the
existing write_rev_file() in terms of this new function.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Implement reading for multi-pack reverse indexes, as described in the
previous patch.
Note that these functions don't yet have any callers, and won't until
multi-pack reachability bitmaps are introduced in a later patch series.
In the meantime, this patch implements some of the infrastructure
necessary to support multi-pack bitmaps.
There are three new functions exposed by the revindex API:
- load_midx_revindex(): loads the reverse index corresponding to the
given multi-pack index.
- midx_to_pack_pos() and pack_pos_to_midx(): these convert between the
multi-pack index and pseudo-pack order.
load_midx_revindex() and pack_pos_to_midx() are both relatively
straightforward.
load_midx_revindex() needs a few functions to be exposed from the midx
API. One to get the checksum of a midx, and another to get the .rev's
filename. Similar to recent changes in the packed_git struct, three new
fields are added to the multi_pack_index struct: one to keep track of
the size, one to keep track of the mmap'd pointer, and another to point
past the header and at the reverse index's data.
pack_pos_to_midx() simply reads the corresponding entry out of the
table.
midx_to_pack_pos() is the trickiest, since it needs to find an object's
position in the psuedo-pack order, but that order can only be recovered
in the .rev file itself. This mapping can be implemented with a binary
search, but note that the thing we're binary searching over isn't an
array of values, but rather a permuted order of those values.
So, when comparing two items, it's helpful to keep in mind the
difference. Instead of a traditional binary search, where you are
comparing two things directly, here we're comparing a (pack, offset)
tuple with an index into the multi-pack index. That index describes
another (pack, offset) tuple, and it is _those_ two tuples that are
compared.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As a prerequisite to implementing multi-pack bitmaps, motivate and
describe the format and ordering of the multi-pack reverse index.
The subsequent patch will implement reading this format, and the patch
after that will implement writing it while producing a multi-pack index.
Co-authored-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a subsequent commit, pack-revindex.c will become responsible for
sorting a list of objects in the "MIDX pack order" (which will be
defined in the following patch). To do so, it will need to be know the
pack identifier and offset within that pack for each object in the MIDX.
The MIDX code already has functions for doing just that
(nth_midxed_offset() and nth_midxed_pack_int_id()), but they are
statically declared.
Since there is no reason that they couldn't be exposed publicly, and
because they are already doing exactly what the caller in
pack-revindex.c will want, expose them publicly so that they can be
reused there.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
write_midx_internal() uses a hashfile to write the multi-pack index, but
discards its checksum. This makes sense, since nothing that takes place
after writing the MIDX cares about its checksum.
That is about to change in a subsequent patch, when the optional
reverse index corresponding to the MIDX will want to include the MIDX's
checksum.
Store the checksum of the MIDX in preparation for that.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A subsequent patch will need to refer back to 'midx_name' later on in
the function. In fact, this variable is already free()'d later on, so
this makes the later free() no longer redundant.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When multiple packs in the multi-pack index contain the same object, the
MIDX machinery must make a choice about which pack it associates with
that object. Prior to this patch, the lowest-ordered[1] pack was always
selected.
Pack selection for duplicate objects is relatively unimportant today,
but it will become important for multi-pack bitmaps. This is because we
can only invoke the pack-reuse mechanism when all of the bits for reused
objects come from the reuse pack (in order to ensure that all reused
deltas can find their base objects in the same pack).
To encourage the pack selection process to prefer one pack over another
(the pack to be preferred is the one a caller would like to later use as
a reuse pack), introduce the concept of a "preferred pack". When
provided, the MIDX code will always prefer an object found in a
preferred pack over any other.
No format changes are required to store the preferred pack, since it
will be able to be inferred with a corresponding MIDX bitmap, by looking
up the pack associated with the object in the first bit position (this
ordering is described in detail in a subsequent commit).
[1]: the ordering is specified by MIDX internals; for our purposes we
can consider the "lowest ordered" pack to be "the one with the
most-recent mtime.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In some scenarios, users may want more history than the repository
offered for cloning, which happens to be a shallow repository, can
give them. But because users don't know it is a shallow repository
until they download it to local, we may want to refuse to clone
this kind of repository, without creating any unnecessary files.
The '--depth=x' option cannot be used as a solution; the source may
be deep enough to give us 'x' commits when cloned, but the user may
later need to deepen the history to arbitrary depth.
Teach '--reject-shallow' option to "git clone" to abort as soon as
we find out that we are cloning from a shallow repository.
Signed-off-by: Li Linchao <lilinchao@oschina.cn>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
save_opts() should save any non-default values. It was intended to do
this, but since most options in struct replay_opts default to 0, it only
saved non-zero values. Unfortunately, this does not always work for
options.edit. Roughly speaking, options.edit had a default value of 0
for cherry-pick but a default value of 1 for revert. Make save_opts()
record a value whenever it differs from the default.
options.edit was also overly simplistic; we had more than two cases.
The behavior that previously existed was as follows:
Non-conflict commits Right after Conflict
revert Edit iff isatty(0) Edit (ignore isatty(0))
cherry-pick No edit See above
Specify --edit Edit (ignore isatty(0)) See above
Specify --no-edit (*) See above
(*) Before stopping for conflicts, No edit is the behavior. After
stopping for conflicts, the --no-edit flag is not saved so see
the first two rows.
However, the expected behavior is:
Non-conflict commits Right after Conflict
revert Edit iff isatty(0) Edit iff isatty(0)
cherry-pick No edit Edit iff isatty(0)
Specify --edit Edit (ignore isatty(0)) Edit (ignore isatty(0))
Specify --no-edit No edit No edit
In order to get the expected behavior, we need to change options.edit
to a tri-state: unspecified, false, or true. When specified, we follow
what it says. When unspecified, we need to check whether the current
commit being created is resolving a conflict as well as consulting
options.action and isatty(0). While at it, add a should_edit() utility
function that compresses options.edit down to a boolean based on the
additional information for the non-conflict case.
continue_single_pick() is the function responsible for resuming after
conflict cases, regardless of whether there is one commit being picked
or many. Make this function stop assuming edit behavior in all cases,
so that it can correctly handle !isatty(0) and specific requests to not
edit the commit message.
Reported-by: Renato Botelho <garga@freebsd.org>
Signed-off-by: Elijah Newren <newren@gmail.com>
Reviewed-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Explain pieces of the format-patch output upfront before the rest
of the documentation starts referring to them.
* jc/doc-format-patch-clarify:
format-patch: give an overview of what a "patch" message is
brian m. carlson
Junio C Hamano
Ævar Arnfjörð Bjarmason
Jeff King
Taylor Blau
Li Linchao
Elijah Newren