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2015-08-03Merge branch 'jc/commit-slab'Junio C Hamano
Memory use reduction when commit-slab facility is used to annotate sparsely (which is not recommended in the first place). * jc/commit-slab: commit-slab: introduce slabname##_peek() function
2015-08-03Merge branch 'bc/gpg-verify-raw'Junio C Hamano
"git verify-tag" and "git verify-commit" have been taught to share more code, and then learned to optionally show the verification message from the underlying GPG implementation. * bc/gpg-verify-raw: verify-tag: add option to print raw gpg status information verify-commit: add option to print raw gpg status information gpg: centralize printing signature buffers gpg: centralize signature check verify-commit: add test for exit status on untrusted signature verify-tag: share code with verify-commit verify-tag: add tests
2015-06-22gpg: centralize signature checkbrian m. carlson
verify-commit and verify-tag both share a central codepath for verifying commits: check_signature. However, verify-tag exited successfully for untrusted signature, while verify-commit exited unsuccessfully. Centralize this signature check and make verify-commit adopt the older verify-tag behavior. This behavior is more logical anyway, as the signature is in fact valid, whether or not there's a path of trust to the author. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22verify-tag: share code with verify-commitbrian m. carlson
verify-tag was executing an entirely different codepath than verify-commit, except for the underlying verify_signed_buffer. Move much of the code from check_commit_signature to a generic check_signature function and adjust both codepaths to call it. Update verify-tag to explicitly output the signature text, as we now call verify_signed_buffer with strbufs to catch the output, which prevents it from being printed automatically. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-11Merge branch 'jk/squelch-missing-link-warning-for-unreachable'Junio C Hamano
Recent "git prune" traverses young unreachable objects to safekeep old objects in the reachability chain from them, which sometimes caused error messages that are unnecessarily alarming. * jk/squelch-missing-link-warning-for-unreachable: suppress errors on missing UNINTERESTING links silence broken link warnings with revs->ignore_missing_links add quieter versions of parse_{tree,commit}
2015-06-01add quieter versions of parse_{tree,commit}Jeff King
When we call parse_commit, it will complain to stderr if the object does not exist or cannot be read. This means that we may produce useless error messages if this situation is expected (e.g., because the object is marked UNINTERESTING, or because revs->ignore_missing_links is set). We can fix this by adding a new "parse_X_gently" form that takes a flag to suppress the messages. The existing "parse_X" form is already gentle in the sense that it returns an error rather than dying, and we could in theory just add a "quiet" flag to it (with existing callers passing "0"). But doing it this way means we do not have to disturb existing callers. Note also that the new flag is "quiet_on_missing", and not just "quiet". We could add a flag to suppress _all_ errors, but besides being a more invasive change (we would have to pass the flag down to sub-functions, too), there is a good reason not to: we would never want to use it. Missing a linked object is expected in some circumstances, but it is never expected to have a malformed commit, or to get a tree when we wanted a commit. We should always complain about these corruptions. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-22commit-slab: introduce slabname##_peek() functionJunio C Hamano
There is no API to ask "Does this commit have associated data in slab?". If an application wants to (1) parse just a few commits at the beginning of a process, (2) store data for only these commits, and then (3) start processing many commits, taking into account the data stored (for a few of them) in the slab, the application would use slabname##_at() to allocate a space to store data in (2), but there is no API other than slabname##_at() to use in step (3). This allocates and wastes new space for these commits the caller is only interested in checking if they have data stored in step (2). Introduce slabname##_peek(), which is similar to slabname##_at() but returns NULL when there is no data already associated to it in such a use case. Helped-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-14commit: convert parts to struct object_idbrian m. carlson
Convert struct commit_graft and necessary local parts of commit.c. Also, convert several constants based on the hex length of an SHA-1 to use GIT_SHA1_HEXSZ, and move several magic constants into variables for readability. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-01-07Merge branch 'jc/merge-bases'Junio C Hamano
The get_merge_bases*() API was easy to misuse by careless copy&paste coders, leaving object flags tainted in the commits that needed to be traversed. * jc/merge-bases: get_merge_bases(): always clean-up object flags bisect: clean flags after checking merge bases
2014-12-22Merge branch 'cc/interpret-trailers-more'Junio C Hamano
"git interpret-trailers" learned to properly handle the "Conflicts:" block at the end. * cc/interpret-trailers-more: trailer: add test with an old style conflict block trailer: reuse ignore_non_trailer() to ignore conflict lines commit: make ignore_non_trailer() non static merge & sequencer: turn "Conflicts:" hint into a comment builtin/commit.c: extract ignore_non_trailer() helper function merge & sequencer: unify codepaths that write "Conflicts:" hint builtin/merge.c: drop a parameter that is never used
2014-11-10commit: make ignore_non_trailer() non staticChristian Couder
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-30get_merge_bases(): always clean-up object flagsJunio C Hamano
The callers of get_merge_bases() can choose to leave object flags used during the merge-base traversal by passing cleanup=0 as a parameter, but in practice a very few callers can afford to do so (namely, "git merge-base"), as they need to compute merge base in preparation for other processing of their own and they need to see the object without contaminate flags. Change the function signature of get_merge_bases_many() and get_merge_bases() to drop the cleanup parameter, so that the majority of the callers do not have to say ", 1" at the end. Give a new get_merge_bases_many_dirty() API to support only a few callers that know they do not need to spend cycles cleaning up the object flags. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-08Merge branch 'jc/push-cert'Junio C Hamano
Allow "git push" request to be signed, so that it can be verified and audited, using the GPG signature of the person who pushed, that the tips of branches at a public repository really point the commits the pusher wanted to, without having to "trust" the server. * jc/push-cert: (24 commits) receive-pack::hmac_sha1(): copy the entire SHA-1 hash out signed push: allow stale nonce in stateless mode signed push: teach smart-HTTP to pass "git push --signed" around signed push: fortify against replay attacks signed push: add "pushee" header to push certificate signed push: remove duplicated protocol info send-pack: send feature request on push-cert packet receive-pack: GPG-validate push certificates push: the beginning of "git push --signed" pack-protocol doc: typofix for PKT-LINE gpg-interface: move parse_signature() to where it should be gpg-interface: move parse_gpg_output() to where it should be send-pack: clarify that cmds_sent is a boolean send-pack: refactor inspecting and resetting status and sending commands send-pack: rename "new_refs" to "need_pack_data" receive-pack: factor out capability string generation send-pack: factor out capability string generation send-pack: always send capabilities send-pack: refactor decision to send update per ref send-pack: move REF_STATUS_REJECT_NODELETE logic a bit higher ...
2014-09-19Merge branch 'da/styles'Junio C Hamano
* da/styles: stylefix: asterisks stick to the variable, not the type
2014-09-15gpg-interface: move parse_gpg_output() to where it should beJunio C Hamano
Earlier, ffb6d7d5 (Move commit GPG signature verification to commit.c, 2013-03-31) moved this helper that used to be in pretty.c (i.e. the output code path) to commit.c for better reusability. It was a good first step in the right direction, but still suffers from a myopic view that commits will be the only thing we would ever want to sign---we would actually want to be able to reuse it even wider. The function interprets what GPG said; gpg-interface is obviously a better place. Move it there. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-02stylefix: asterisks stick to the variable, not the typeDavid Aguilar
Signed-off-by: David Aguilar <davvid@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-27record_author_date(): use find_commit_header()Jeff King
This saves us some manual parsing and makes the code more readable. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-27record_author_date(): fix memory leak on malformed commitJeff King
If we hit the end-of-header without finding an "author" line, we just return from the function. We should jump to the fail_exit path to clean up the buffer that we may have allocated. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-27commit: provide a function to find a header in a bufferJeff King
Usually when we parse a commit, we read it line by line and handle each individual line (e.g., parse_commit and parse_commit_header). Sometimes, however, we only care about extracting a single header. Code in this situation is stuck doing an ad-hoc parse of the commit buffer. Let's provide a reusable function to locate a header within the commit. The code is modeled after pretty.c's get_header, which is used to extract the encoding. Since some callers may not have the "struct commit" to go along with the buffer, we drop that parameter. The only thing lost is a warning for truncated commits, but that's OK. This shouldn't happen in practice, and even if it does, there's no particular reason that this function needs to complain about it. It either finds the header it was asked for, or it doesn't (and in the latter case, the caller will typically complain). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-28add object_as_type helper for casting objectsJeff King
When we call lookup_commit, lookup_tree, etc, the logic goes something like: 1. Look for an existing object struct. If we don't have one, allocate and return a new one. 2. Double check that any object we have is the expected type (and complain and return NULL otherwise). 3. Convert an object with type OBJ_NONE (from a prior call to lookup_unknown_object) to the expected type. We can encapsulate steps 2 and 3 in a helper function which checks whether we have the expected object type, converts OBJ_NONE as appropriate, and returns the object. Not only does this shorten the code, but it also provides one central location for converting OBJ_NONE objects into objects of other types. Future patches will use that to enforce type-specific invariants. Since this is a refactoring, we would want it to behave exactly as the current code. It takes a little reasoning to see that this is the case: - for lookup_{commit,tree,etc} functions, we are just pulling steps 2 and 3 into a function that does the same thing. - for the call in peel_object, we currently only do step 3 (but we want to consolidate it with the others, as mentioned above). However, step 2 is a noop here, as the surrounding conditional makes sure we have OBJ_NONE (which we want to keep to avoid an extraneous call to sha1_object_info). - for the call in lookup_commit_reference_gently, we are currently doing step 2 but not step 3. However, step 3 is a noop here. The object we got will have just come from deref_tag, which must have figured out the type for each object in order to know when to stop peeling. Therefore the type will never be OBJ_NONE. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-28move setting of object->type to alloc_* functionsJeff King
The "struct object" type implements basic object polymorphism. Individual instances are allocated as concrete types (or as a union type that can store any object), and a "struct object *" can be cast into its real type after examining its "type" enum. This means it is dangerous to have a type field that does not match the allocation (e.g., setting the type field of a "struct blob" to "OBJ_COMMIT" would mean that a reader might read past the allocated memory). In most of the current code this is not a problem; the first thing we do after allocating an object is usually to set its type field by passing it to create_object. However, the virtual commits we create in merge-recursive.c do not ever get their type set. This does not seem to have caused problems in practice, though (presumably because we always pass around a "struct commit" pointer and never even look at the type). We can fix this oversight and also make it harder for future code to get it wrong by setting the type directly in the object allocation functions. This will also make it easier to fix problems with commit index allocation, as we know that any object allocated by alloc_commit_node will meet the invariant that an object with an OBJ_COMMIT type field will have a unique index number. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-27Merge branch 'cc/replace-graft'Junio C Hamano
"git replace" learned a "--graft" option to rewrite parents of a commit. * cc/replace-graft: replace: add test for --graft with a mergetag replace: check mergetags when using --graft replace: add test for --graft with signed commit replace: remove signature when using --graft contrib: add convert-grafts-to-replace-refs.sh Documentation: replace: add --graft option replace: add test for --graft replace: add --graft option replace: cleanup redirection style in tests
2014-07-27Merge branch 'jk/stable-prio-queue'Junio C Hamano
* jk/stable-prio-queue: t5539: update a flaky test paint_down_to_common: use prio_queue prio-queue: make output stable with respect to insertion prio-queue: factor out compare and swap operations
2014-07-22Merge branch 'rs/code-cleaning'Junio C Hamano
* rs/code-cleaning: remote-testsvn: use internal argv_array of struct child_process in cmd_import() bundle: use internal argv_array of struct child_process in create_bundle() fast-import: use hashcmp() for SHA1 hash comparison transport: simplify fetch_objs_via_rsync() using argv_array run-command: use internal argv_array of struct child_process in run_hook_ve() use commit_list_count() to count the members of commit_lists strbuf: use strbuf_addstr() for adding C strings
2014-07-22Merge branch 'jk/alloc-commit-id'Junio C Hamano
Make sure all in-core commit objects are assigned a unique number so that they can be annotated using the commit-slab API. * jk/alloc-commit-id: diff-tree: avoid lookup_unknown_object object_as_type: set commit index alloc: factor out commit index add object_as_type helper for casting objects parse_object_buffer: do not set object type move setting of object->type to alloc_* functions alloc: write out allocator definitions alloc.c: remove the alloc_raw_commit_node() function
2014-07-22Merge branch 'bg/xcalloc-nmemb-then-size' into maintJunio C Hamano
* bg/xcalloc-nmemb-then-size: transport-helper.c: rearrange xcalloc arguments remote.c: rearrange xcalloc arguments reflog-walk.c: rearrange xcalloc arguments pack-revindex.c: rearrange xcalloc arguments notes.c: rearrange xcalloc arguments imap-send.c: rearrange xcalloc arguments http-push.c: rearrange xcalloc arguments diff.c: rearrange xcalloc arguments config.c: rearrange xcalloc arguments commit.c: rearrange xcalloc arguments builtin/remote.c: rearrange xcalloc arguments builtin/ls-remote.c: rearrange xcalloc arguments
2014-07-21replace: remove signature when using --graftChristian Couder
It could be misleading to keep a signature in a replacement commit, so let's remove it. Note that there should probably be a way to sign the replacement commit created when using --graft, but this can be dealt with in another commit or patch series. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-21Merge branch 'cc/for-each-mergetag'Junio C Hamano
* cc/for-each-mergetag: commit: add for_each_mergetag()
2014-07-17use commit_list_count() to count the members of commit_listsRené Scharfe
Call commit_list_count() instead of open-coding it repeatedly. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-16Merge branch 'rs/code-cleaning'Junio C Hamano
* rs/code-cleaning: fsck: simplify fsck_commit_buffer() by using commit_list_count() commit: use commit_list_append() instead of duplicating its code merge: simplify merge_trivial() by using commit_list_append() use strbuf_addch for adding single characters use strbuf_addbuf for adding strbufs
2014-07-15paint_down_to_common: use prio_queueJeff King
When we are traversing to find merge bases, we keep our usual commit_list of commits to process, sorted by their commit timestamp. As we add each parent to the list, we have to spend "O(width of history)" to do the insertion, where the width of history is the number of simultaneous lines of development. If we instead use a heap-based priority queue, we can do these insertions in "O(log width)" time. This provides minor speedups to merge-base calculations (timings in linux.git, warm cache, best-of-five): [before] $ git merge-base HEAD v2.6.12 real 0m3.251s user 0m3.148s sys 0m0.104s [after] $ git merge-base HEAD v2.6.12 real 0m3.234s user 0m3.108s sys 0m0.128s That's only an 0.5% speedup, but it does help protect us against pathological cases. While we are munging the "interesting" function, we also take the opportunity to give it a more descriptive name, and convert the return value to an int (we returned the first interesting commit, but nobody ever looked at it). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-14add object_as_type helper for casting objectsJeff King
When we call lookup_commit, lookup_tree, etc, the logic goes something like: 1. Look for an existing object struct. If we don't have one, allocate and return a new one. 2. Double check that any object we have is the expected type (and complain and return NULL otherwise). 3. Convert an object with type OBJ_NONE (from a prior call to lookup_unknown_object) to the expected type. We can encapsulate steps 2 and 3 in a helper function which checks whether we have the expected object type, converts OBJ_NONE as appropriate, and returns the object. Not only does this shorten the code, but it also provides one central location for converting OBJ_NONE objects into objects of other types. Future patches will use that to enforce type-specific invariants. Since this is a refactoring, we would want it to behave exactly as the current code. It takes a little reasoning to see that this is the case: - for lookup_{commit,tree,etc} functions, we are just pulling steps 2 and 3 into a function that does the same thing. - for the call in peel_object, we currently only do step 3 (but we want to consolidate it with the others, as mentioned above). However, step 2 is a noop here, as the surrounding conditional makes sure we have OBJ_NONE (which we want to keep to avoid an extraneous call to sha1_object_info). - for the call in lookup_commit_reference_gently, we are currently doing step 2 but not step 3. However, step 3 is a noop here. The object we got will have just come from deref_tag, which must have figured out the type for each object in order to know when to stop peeling. Therefore the type will never be OBJ_NONE. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-14move setting of object->type to alloc_* functionsJeff King
The "struct object" type implements basic object polymorphism. Individual instances are allocated as concrete types (or as a union type that can store any object), and a "struct object *" can be cast into its real type after examining its "type" enum. This means it is dangerous to have a type field that does not match the allocation (e.g., setting the type field of a "struct blob" to "OBJ_COMMIT" would mean that a reader might read past the allocated memory). In most of the current code this is not a problem; the first thing we do after allocating an object is usually to set its type field by passing it to create_object. However, the virtual commits we create in merge-recursive.c do not ever get their type set. This does not seem to have caused problems in practice, though (presumably because we always pass around a "struct commit" pointer and never even look at the type). We can fix this oversight and also make it harder for future code to get it wrong by setting the type directly in the object allocation functions. This will also make it easier to fix problems with commit index allocation, as we know that any object allocated by alloc_commit_node will meet the invariant that an object with an OBJ_COMMIT type field will have a unique index number. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-10commit: use commit_list_append() instead of duplicating its codeRené Scharfe
Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-10Merge branch 'mg/verify-commit'Junio C Hamano
Add 'verify-commit' to be used in a way similar to 'verify-tag' is used. Further work on verifying the mergetags might be needed. * mg/verify-commit: t7510: test verify-commit t7510: exit for loop with test result verify-commit: scriptable commit signature verification gpg-interface: provide access to the payload gpg-interface: provide clear helper for struct signature_check
2014-07-09Merge branch 'jk/skip-prefix'Junio C Hamano
* jk/skip-prefix: http-push: refactor parsing of remote object names imap-send: use skip_prefix instead of using magic numbers use skip_prefix to avoid repeated calculations git: avoid magic number with skip_prefix fetch-pack: refactor parsing in get_ack fast-import: refactor parsing of spaces stat_opt: check extra strlen call daemon: use skip_prefix to avoid magic numbers fast-import: use skip_prefix for parsing input use skip_prefix to avoid repeating strings use skip_prefix to avoid magic numbers transport-helper: avoid reading past end-of-string fast-import: fix read of uninitialized argv memory apply: use skip_prefix instead of raw addition refactor skip_prefix to return a boolean avoid using skip_prefix as a boolean daemon: mark some strings as const parse_diff_color_slot: drop ofs parameter
2014-07-07commit: add for_each_mergetag()Christian Couder
In the same way as there is for_each_ref() to iterate on refs, for_each_mergetag() allows the caller to iterate on the mergetags of a given commit. Use it to rewrite show_mergetag() used in "git log". Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-02Merge branch 'jk/commit-buffer-length'Junio C Hamano
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
2014-06-23gpg-interface: provide access to the payloadMichael J Gruber
In contrast to tag signatures, commit signatures are put into the header, that is between the other header parts and commit messages. Provide access to the commit content sans the signature, which is the payload that is actually signed. Commit signature verification does the parsing anyways, and callers may wish to act on or display the commit object sans the signature. Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-20refactor skip_prefix to return a booleanJeff King
The skip_prefix() function returns a pointer to the content past the prefix, or NULL if the prefix was not found. While this is nice and simple, in practice it makes it hard to use for two reasons: 1. When you want to conditionally skip or keep the string as-is, you have to introduce a temporary variable. For example: tmp = skip_prefix(buf, "foo"); if (tmp) buf = tmp; 2. It is verbose to check the outcome in a conditional, as you need extra parentheses to silence compiler warnings. For example: if ((cp = skip_prefix(buf, "foo")) /* do something with cp */ Both of these make it harder to use for long if-chains, and we tend to use starts_with() instead. However, the first line of "do something" is often to then skip forward in buf past the prefix, either using a magic constant or with an extra strlen(3) (which is generally computed at compile time, but means we are repeating ourselves). This patch refactors skip_prefix() to return a simple boolean, and to provide the pointer value as an out-parameter. If the prefix is not found, the out-parameter is untouched. This lets you write: if (skip_prefix(arg, "foo ", &arg)) do_foo(arg); else if (skip_prefix(arg, "bar ", &arg)) do_bar(arg); Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13reuse cached commit buffer when parsing signaturesJeff King
When we call show_signature or show_mergetag, we read the commit object fresh via read_sha1_file and reparse its headers. However, in most cases we already have the object data available, attached to the "struct commit". This is partially laziness in dealing with the memory allocation issues, but partially defensive programming, in that we would always want to verify a clean version of the buffer (not one that might have been munged by other users of the commit). However, we do not currently ever munge the commit buffer, and not using the already-available buffer carries a fairly big performance penalty when we are looking at a large number of commits. Here are timings on linux.git: [baseline, no signatures] $ time git log >/dev/null real 0m4.902s user 0m4.784s sys 0m0.120s [before] $ time git log --show-signature >/dev/null real 0m14.735s user 0m9.964s sys 0m0.944s [after] $ time git log --show-signature >/dev/null real 0m9.981s user 0m5.260s sys 0m0.936s Note that our user CPU time drops almost in half, close to the non-signature case, but we do still spend more wall-clock and system time, presumably from dealing with gpg. An alternative to this is to note that most commits do not have signatures (less than 1% in this repo), yet we pay the re-parsing cost for every commit just to find out if it has a mergetag or signature. If we checked that when parsing the commit initially, we could avoid re-examining most commits later on. Even if we did pursue that direction, however, this would still speed up the cases where we _do_ have signatures. So it's probably worth doing either way. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13commit: record buffer length in cacheJeff King
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>
2014-06-13commit: convert commit->buffer to a slabJeff King
This will make it easier to manage the buffer cache independently of the "struct commit" objects. It also shrinks "struct commit" by one pointer, which may be helpful. Unfortunately it does not reduce the max memory size of something like "rev-list", because rev-list uses get_cached_commit_buffer() to decide not to show each commit's output (and due to the design of slab_at, accessing the slab requires us to extend it, allocating exactly the same number of buffer pointers we dropped from the commit structs). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13use get_commit_buffer to avoid duplicate codeJeff King
For both of these sites, we already do the "fallback to read_sha1_file" trick. But we can shorten the code by just using get_commit_buffer. Note that the error cases are slightly different when read_sha1_file fails. get_commit_buffer will die() if the object cannot be loaded, or is a non-commit. For get_sha1_oneline, this will almost certainly never happen, as we will have just called parse_object (and if it does, it's probably worth complaining about). For record_author_date, the new behavior is probably better; we notify the user of the error instead of silently ignoring it. And because it's used only for sorting by author-date, somebody examining a corrupt repo can fallback to the regular traversal order. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13provide helpers to access the commit bufferJeff King
Many sites look at commit->buffer to get more detailed information than what is in the parsed commit struct. However, we sometimes drop commit->buffer to save memory, in which case the caller would need to read the object afresh. Some callers do this (leading to duplicated code), and others do not (which opens the possibility of a segfault if somebody else frees the buffer). Let's provide a pair of helpers, "get" and "unuse", that let callers easily get the buffer. They will use the cached buffer when possible, and otherwise load from disk using read_sha1_file. Note that we also need to add a "get_cached" variant which returns NULL when we do not have a cached buffer. At first glance this seems to defeat the purpose of "get", which is to always provide a return value. However, some log code paths actually use the NULL-ness of commit->buffer as a boolean flag to decide whether to try printing the commit. At least for now, we want to continue supporting that use. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13provide a helper to set the commit bufferJeff King
Right now this is just a one-liner, but abstracting it will make it easier to change later. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13provide a helper to free commit bufferJeff King
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>
2014-06-12commit: push commit_index update into alloc_commit_nodeJeff King
Whenever we create a commit object via lookup_commit, we give it a unique index to be used with the commit-slab API. The theory is that any "struct commit" we create would follow this code path, so any such struct would get an index. However, callers could use alloc_commit_node() directly (and get multiple commits with index 0). Let's push the indexing into alloc_commit_node so that it's hard for callers to get it wrong. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-12commit_tree: take a pointer/len pair rather than a const strbufJeff King
While strbufs are pretty common throughout our code, it is more flexible for functions to take a pointer/len pair than a strbuf. It's easy to turn a strbuf into such a pair (by dereferencing its members), but less easy to go the other way (you can strbuf_attach, but that has implications about memory ownership). This patch teaches commit_tree (and its associated callers and sub-functions) to take such a pair for the commit message rather than a strbuf. This makes passing the buffer around slightly more verbose, but means we can get rid of some dangerous strbuf_attach calls in the next patch. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-05-27commit.c: rearrange xcalloc argumentsBrian Gesiak
xcalloc() takes two arguments: the number of elements and their size. reduce_heads() passes the arguments in reverse order, passing the size of a commit*, followed by the number of commit* to be allocated. Rearrange them so they are in the correct order. Signed-off-by: Brian Gesiak <modocache@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>