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Author SHA1 Message Date
Junio C Hamano
d829d491ee Merge branch 'bc/hash-transition-part-15'
More codepaths are moving away from hardcoded hash sizes.

* bc/hash-transition-part-15:
  rerere: convert to use the_hash_algo
  submodule: make zero-oid comparison hash function agnostic
  apply: rename new_sha1_prefix and old_sha1_prefix
  apply: replace hard-coded constants
  tag: express constant in terms of the_hash_algo
  transport: use parse_oid_hex instead of a constant
  upload-pack: express constants in terms of the_hash_algo
  refs/packed-backend: express constants using the_hash_algo
  packfile: express constants in terms of the_hash_algo
  pack-revindex: express constants in terms of the_hash_algo
  builtin/fetch-pack: remove constants with parse_oid_hex
  builtin/mktree: remove hard-coded constant
  builtin/repack: replace hard-coded constants
  pack-bitmap-write: use GIT_MAX_RAWSZ for allocation
  object_id.cocci: match only expressions of type 'struct object_id'
2018-10-30 15:43:42 +09:00
Junio C Hamano
11877b9ebe Merge branch 'nd/the-index'
Various codepaths in the core-ish part learn to work on an
arbitrary in-core index structure, not necessarily the default
instance "the_index".

* nd/the-index: (23 commits)
  revision.c: reduce implicit dependency the_repository
  revision.c: remove implicit dependency on the_index
  ws.c: remove implicit dependency on the_index
  tree-diff.c: remove implicit dependency on the_index
  submodule.c: remove implicit dependency on the_index
  line-range.c: remove implicit dependency on the_index
  userdiff.c: remove implicit dependency on the_index
  rerere.c: remove implicit dependency on the_index
  sha1-file.c: remove implicit dependency on the_index
  patch-ids.c: remove implicit dependency on the_index
  merge.c: remove implicit dependency on the_index
  merge-blobs.c: remove implicit dependency on the_index
  ll-merge.c: remove implicit dependency on the_index
  diff-lib.c: remove implicit dependency on the_index
  read-cache.c: remove implicit dependency on the_index
  diff.c: remove implicit dependency on the_index
  grep.c: remove implicit dependency on the_index
  diff.c: remove the_index dependency in textconv() functions
  blame.c: rename "repo" argument to "r"
  combine-diff.c: remove implicit dependency on the_index
  ...
2018-10-19 13:34:02 +09:00
brian m. carlson
0d7c419a94 rerere: convert to use the_hash_algo
Since this data is stored in the .git directory, it makes sense for us
to use the same hash algorithm for it as for everything else.  Convert
the remaining uses of SHA-1 to use the_hash_algo.  Use GIT_MAX_RAWSZ for
allocations.  Rename various struct members, local variables, and a
function to be named "hash" instead of "sha1".

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-15 12:53:16 +09:00
Junio C Hamano
bd3941a0ae Merge branch 'en/rerere-multi-stage-1-fix'
A corner case bugfix in "git rerere" code.

* en/rerere-multi-stage-1-fix:
  rerere: avoid buffer overrun
  t4200: demonstrate rerere segfault on specially crafted merge
2018-09-24 10:30:48 -07:00
Nguyễn Thái Ngọc Duy
35843b1123 rerere.c: remove implicit dependency on the_index
The reason rerere(), rerere_forget() and rerere_remaining() take a
struct repository instead of struct index_state is not obvious from
the patch:

Deep in update_paths() and find_conflict(), hold_locked_index() and
read_index() are called. These functions assumes the index path at
$GIT_DIR/index which is not always true when you take an arbitrary
index state. Taking a repository will allow us to point to the right
index path later when we replace them with repo_ versions.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-09-21 09:48:11 -07:00
Nguyễn Thái Ngọc Duy
32eaa46883 ll-merge.c: remove implicit dependency on the_index
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-09-21 09:48:10 -07:00
Junio C Hamano
39006893f9 Merge branch 'tg/rerere'
Fixes to "git rerere" corner cases, especially when conflict
markers cannot be parsed in the file.

* tg/rerere:
  rerere: recalculate conflict ID when unresolved conflict is committed
  rerere: teach rerere to handle nested conflicts
  rerere: return strbuf from handle path
  rerere: factor out handle_conflict function
  rerere: only return whether a path has conflicts or not
  rerere: fix crash with files rerere can't handle
  rerere: add documentation for conflict normalization
  rerere: mark strings for translation
  rerere: wrap paths in output in sq
  rerere: lowercase error messages
  rerere: unify error messages when read_cache fails
2018-09-17 13:53:51 -07:00
Elijah Newren
ad2bf0d9b4 rerere: avoid buffer overrun
check_one_conflict() compares `i` to `active_nr` in two places to avoid
buffer overruns, but left out an important third location.

The code did used to have a check here comparing i to active_nr, back
before commit fb70a06da2 ("rerere: fix an off-by-one non-bug",
2015-06-28), however the code at the time used an 'if' rather than a
'while' meaning back then that this loop could not have read past the
end of the array, making the check unnecessary and it was removed.
Unfortunately, in commit 5eda906b28 ("rerere: handle conflicts with
multiple stage #1 entries", 2015-07-24), the 'if' was changed to a
'while' and the check comparing i and active_nr was not re-instated,
leading to this problem.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-09-11 13:43:23 -07:00
Nguyễn Thái Ngọc Duy
6d2df284e7 dir.c: remove an implicit dependency on the_index in pathspec code
Make the match_patchspec API and friends take an index_state instead
of assuming the_index in dir.c. All external call sites are converted
blindly to keep the patch simple and retain current behavior.
Individual call sites may receive further updates to use the right
index instead of the_index.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-13 14:14:42 -07:00
Thomas Gummerer
bd7dfa543e rerere: recalculate conflict ID when unresolved conflict is committed
Currently when a user doesn't resolve a conflict, commits the results,
and does an operation which creates another conflict, rerere will use
the ID of the previously unresolved conflict for the new conflict.
This is because the conflict is kept in the MERGE_RR file, which
'rerere' reads every time it is invoked.

After the new conflict is solved, rerere will record the resolution
with the ID of the old conflict.  So in order to replay the conflict,
both merges would have to be re-done, instead of just the last one, in
order for rerere to be able to automatically resolve the conflict.

Instead of that, assign a new conflict ID if there are still conflicts
in a file and the file had conflicts at a previous step.  This ID
matches the conflict we actually resolved at the corresponding step.

Note that there are no backwards compatibility worries here, as rerere
would have failed to even normalize the conflict before this patch
series.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-06 13:22:35 -07:00
Thomas Gummerer
4af32207bc rerere: teach rerere to handle nested conflicts
Currently rerere can't handle nested conflicts and will error out when
it encounters such conflicts.  Do that by recursively calling the
'handle_conflict' function to normalize the conflict.

Note that a conflict like this would only be produced if a user
commits a file with conflict markers, and gets a conflict including
that in a susbsequent operation.

The conflict ID calculation here deserves some explanation:

As we are using the same handle_conflict function, the nested conflict
is normalized the same way as for non-nested conflicts, which means
the ancestor in the diff3 case is stripped out, and the parts of the
conflict are ordered alphabetically.

The conflict ID is however is only calculated in the top level
handle_conflict call, so it will include the markers that 'rerere'
adds to the output.  e.g. say there's the following conflict:

    <<<<<<< HEAD
    1
    =======
    <<<<<<< HEAD
    3
    =======
    2
    >>>>>>> branch-2
    >>>>>>> branch-3~

it would be recorde as follows in the preimage:

    <<<<<<<
    1
    =======
    <<<<<<<
    2
    =======
    3
    >>>>>>>
    >>>>>>>

and the conflict ID would be calculated as

    sha1(1<NUL><<<<<<<
    2
    =======
    3
    >>>>>>><NUL>)

Stripping out vs. leaving the conflict markers in place in the inner
conflict should have no practical impact, but it simplifies the
implementation.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-06 13:22:35 -07:00
Thomas Gummerer
5ebbdad344 rerere: return strbuf from handle path
Currently we write the conflict to disk directly in the handle_path
function.  To make it re-usable for nested conflicts, instead of
writing the conflict out directly, store it in a strbuf and let the
caller write it out.

This does mean some slight increase in memory usage, however that
increase is limited to the size of the largest conflict we've
currently processed.  We already keep one copy of the conflict in
memory, and it shouldn't be too large, so the increase in memory usage
seems acceptable.

As a bonus this lets us get replace the rerere_io_putconflict function
with a trivial two line function.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-06 13:22:35 -07:00
Thomas Gummerer
c0f16f8e14 rerere: factor out handle_conflict function
Factor out the handle_conflict function, which handles a single
conflict in a path.  This is in preparation for a subsequent commit,
where this function will be re-used.

Note that this does change the behaviour of 'git rerere' slightly.
Where previously we'd consider all files where an unmatched conflict
marker is found as invalid, we now only consider files invalid when
the "ours" conflict marker ("<<<<<<< <text>") is unmatched, not when
other conflict markers (e.g. "=======") is unmatched.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-06 13:22:35 -07:00
Thomas Gummerer
221444f5d1 rerere: only return whether a path has conflicts or not
We currently return the exact number of conflict hunks a certain path
has from the 'handle_paths' function.  However all of its callers only
care whether there are conflicts or not or if there is an error.
Return only that information, and document that only that information
is returned.  This will simplify the code in the subsequent steps.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-06 13:22:35 -07:00
Thomas Gummerer
93406a282f rerere: fix crash with files rerere can't handle
Currently when a user does a conflict resolution and ends it (in any
way that calls 'git rerere' again) with a file 'rerere' can't handle,
subsequent rerere operations that are interested in that path, such as
'rerere clear' or 'rerere forget <path>' will fail, or even worse in
the case of 'rerere clear' segfault.

Such states include nested conflicts, or a conflict marker that
doesn't have any match.

This is because 'git rerere' calculates a conflict file and writes it
to the MERGE_RR file.  When the user then changes the file in any way
rerere can't handle, and then calls 'git rerere' on it again to record
the conflict resolution, the handle_file function fails, and removes
the 'preimage' file in the rr-cache in the process, while leaving the
ID in the MERGE_RR file.

Now when 'rerere clear' is run, it reads the ID from the MERGE_RR
file, however the 'fit_variant' function for the ID is never called as
the 'preimage' file does not exist anymore.  This means
'collection->status' in 'has_rerere_resolution' is NULL, and the
command will crash.

To fix this, remove the rerere ID from the MERGE_RR file in the case
when we can't handle it, just after the 'preimage' file was removed
and remove the corresponding variant from .git/rr-cache/.  Removing it
unconditionally is fine here, because if the user would have resolved
the conflict and ran rerere, the entry would no longer be in the
MERGE_RR file, so we wouldn't have this problem in the first place,
while if the conflict was not resolved.

Currently there is nothing left in this folder, as the 'preimage'
was already deleted by the 'handle_file' function, so 'remove_variant'
is a no-op.  Still call the function, to make sure we clean everything
up, in case we add some other files corresponding to a variant in the
future.

Note that other variants that have the same conflict ID will not be
touched.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-06 13:22:35 -07:00
Thomas Gummerer
fb90dca34c rerere: add documentation for conflict normalization
Add some documentation for the logic behind the conflict normalization
in rerere.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-06 13:22:34 -07:00
Thomas Gummerer
2373b65059 rerere: mark strings for translation
'git rerere' is considered a porcelain command and as such its output
should be translated.  Its functionality is also only enabled through
a config setting, so scripts really shouldn't rely on the output
either way.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-06 13:22:34 -07:00
Junio C Hamano
00624d608c Merge branch 'sb/object-store-grafts'
The conversion to pass "the_repository" and then "a_repository"
throughout the object access API continues.

* sb/object-store-grafts:
  commit: allow lookup_commit_graft to handle arbitrary repositories
  commit: allow prepare_commit_graft to handle arbitrary repositories
  shallow: migrate shallow information into the object parser
  path.c: migrate global git_path_* to take a repository argument
  cache: convert get_graft_file to handle arbitrary repositories
  commit: convert read_graft_file to handle arbitrary repositories
  commit: convert register_commit_graft to handle arbitrary repositories
  commit: convert commit_graft_pos() to handle arbitrary repositories
  shallow: add repository argument to is_repository_shallow
  shallow: add repository argument to check_shallow_file_for_update
  shallow: add repository argument to register_shallow
  shallow: add repository argument to set_alternate_shallow_file
  commit: add repository argument to lookup_commit_graft
  commit: add repository argument to prepare_commit_graft
  commit: add repository argument to read_graft_file
  commit: add repository argument to register_commit_graft
  commit: add repository argument to commit_graft_pos
  object: move grafts to object parser
  object-store: move object access functions to object-store.h
2018-07-18 12:20:28 -07:00
Thomas Gummerer
28fc9abd3f rerere: wrap paths in output in sq
It looks like most paths in the output in the git codebase are wrapped
in single quotes.  Standardize on that in rerere as well.

Apart from being more consistent, this also makes some of the strings
match strings that are already translated in other parts of the
codebase, thus reducing the work for translators, when the strings are
marked for translation in a subsequent commit.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-16 14:03:24 -07:00
Thomas Gummerer
c5d1d13239 rerere: lowercase error messages
Documentation/CodingGuidelines mentions that error messages should be
lowercase.  Prior to marking them for translation follow that pattern
in rerere as well, so translators won't have to translate messages
that don't conform to our guidelines.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-16 14:03:24 -07:00
Thomas Gummerer
e69db0b323 rerere: unify error messages when read_cache fails
We have multiple different variants of the error message we show to
the user if 'read_cache' fails.  The "Could not read index" variant we
are using in 'rerere.c' is currently not used anywhere in translated
form.

As a subsequent commit will mark all output that comes from 'rerere.c'
for translation, make the life of the translators a little bit easier
by using a string that is used elsewhere, and marked for translation
there, and thus most likely already translated.

"index file corrupt" seems to be the most common error message we show
when 'read_cache' fails, so use that here as well.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-16 14:03:24 -07:00
Junio C Hamano
2f76ebc93c Merge branch 'ma/lockfile-cleanup'
Code clean-up to adjust to a more recent lockfile API convention that
allows lockfile instances kept on the stack.

* ma/lockfile-cleanup:
  lock_file: move static locks into functions
  lock_file: make function-local locks non-static
  refs.c: do not die if locking fails in `delete_pseudoref()`
  refs.c: do not die if locking fails in `write_pseudoref()`
  t/helper/test-write-cache: clean up lock-handling
2018-05-30 14:04:05 +09:00
Stefan Beller
102de880d2 path.c: migrate global git_path_* to take a repository argument
Migrate all git_path_* functions that are defined in path.c to take a
repository argument. Unlike other patches in this series, do not use the
 #define trick, as we rewrite the whole function, which is rather small.

This doesn't migrate all the functions, as other builtins have their own
local path functions defined using GIT_PATH_FUNC. So keep that macro
around to serve the other locations.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-18 08:13:10 +09:00
Stefan Beller
cbd53a2193 object-store: move object access functions to object-store.h
This should make these functions easier to find and cache.h less
overwhelming to read.

In particular, this moves:
- read_object_file
- oid_object_info
- write_object_file

As a result, most of the codebase needs to #include object-store.h.
In this patch the #include is only added to files that would fail to
compile otherwise.  It would be better to #include wherever
identifiers from the header are used.  That can happen later
when we have better tooling for it.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-16 11:42:03 +09:00
Martin Ågren
0fa5a2ed8d lock_file: move static locks into functions
Placing `struct lock_file`s on the stack used to be a bad idea, because
the temp- and lockfile-machinery would keep a pointer into the struct.
But after 076aa2cbd (tempfile: auto-allocate tempfiles on heap,
2017-09-05), we can safely have lockfiles on the stack. (This applies
even if a user returns early, leaving a locked lock behind.)

Each of these `struct lock_file`s is used from within a single function.
Move them into the respective functions to make the scope clearer and
drop the staticness.

For good measure, I have inspected these sites and come to believe that
they always release the lock, with the possible exception of bailing out
using `die()` or `exit()` or by returning from a `cmd_foo()`.

As pointed out by Jeff King, it would be bad if someone held on to a
`struct lock_file *` for some reason. After some grepping, I agree with
his findings: no-one appears to be doing that.

After this commit, the remaining occurrences of "static struct
lock_file" are locks that are used from within different functions. That
is, they need to remain static. (Short of more intrusive changes like
passing around pointers to non-static locks.)

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-10 14:55:40 +09:00
Junio C Hamano
a5bbc29994 Merge branch 'bc/object-id'
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
  ...
2018-04-10 08:25:45 +09:00
brian m. carlson
b4f5aca40e sha1_file: convert read_sha1_file to struct object_id
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>
2018-03-14 09:23:50 -07:00
Martin Ågren
610008146e write_locked_index(): add flag to avoid writing unchanged index
We have several callers like

	if (active_cache_changed && write_locked_index(...))
		handle_error();
	rollback_lock_file(...);

where the final rollback is needed because "!active_cache_changed"
shortcuts the if-expression. There are also a few variants of this,
including some if-else constructs that make it more clear when the
explicit rollback is really needed.

Teach `write_locked_index()` to take a new flag SKIP_IF_UNCHANGED and
simplify the callers. Leave the most complicated of the callers (in
builtin/update-index.c) unchanged. Rewriting it to use this new flag
would end up duplicating logic.

We could have made the new flag behave the other way round
("FORCE_WRITE"), but that could break existing users behind their backs.
Let's take the more conservative approach. We can still migrate existing
callers to use our new flag. Later we might even be able to flip the
default, possibly without entirely ignoring the risk to in-flight or
out-of-tree topics.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-01 13:28:01 -08:00
SZEDER Gábor
f919ffebed Use MOVE_ARRAY
Use the helper macro MOVE_ARRAY to move arrays.  This is shorter and
safer, as it automatically infers the size of elements.

Patch generated by Coccinelle and contrib/coccinelle/array.cocci in
Travis CI's static analysis build job.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-01-22 11:32:51 -08:00
Junio C Hamano
c50424a6f0 Merge branch 'jk/write-in-full-fix'
Many codepaths did not diagnose write failures correctly when disks
go full, due to their misuse of write_in_full() helper function,
which have been corrected.

* jk/write-in-full-fix:
  read_pack_header: handle signed/unsigned comparison in read result
  config: flip return value of store_write_*()
  notes-merge: use ssize_t for write_in_full() return value
  pkt-line: check write_in_full() errors against "< 0"
  convert less-trivial versions of "write_in_full() != len"
  avoid "write_in_full(fd, buf, len) != len" pattern
  get-tar-commit-id: check write_in_full() return against 0
  config: avoid "write_in_full(fd, buf, len) < len" pattern
2017-09-25 15:24:06 +09:00
Jeff King
06f46f237a avoid "write_in_full(fd, buf, len) != len" pattern
The return value of write_in_full() is either "-1", or the
requested number of bytes[1]. If we make a partial write
before seeing an error, we still return -1, not a partial
value. This goes back to f6aa66cb95 (write_in_full: really
write in full or return error on disk full., 2007-01-11).

So checking anything except "was the return value negative"
is pointless. And there are a couple of reasons not to do
so:

  1. It can do a funny signed/unsigned comparison. If your
     "len" is signed (e.g., a size_t) then the compiler will
     promote the "-1" to its unsigned variant.

     This works out for "!= len" (unless you really were
     trying to write the maximum size_t bytes), but is a
     bug if you check "< len" (an example of which was fixed
     recently in config.c).

     We should avoid promoting the mental model that you
     need to check the length at all, so that new sites are
     not tempted to copy us.

  2. Checking for a negative value is shorter to type,
     especially when the length is an expression.

  3. Linus says so. In d34cf19b89 (Clean up write_in_full()
     users, 2007-01-11), right after the write_in_full()
     semantics were changed, he wrote:

       I really wish every "write_in_full()" user would just
       check against "<0" now, but this fixes the nasty and
       stupid ones.

     Appeals to authority aside, this makes it clear that
     writing it this way does not have an intentional
     benefit. It's a historical curiosity that we never
     bothered to clean up (and which was undoubtedly
     cargo-culted into new sites).

So let's convert these obviously-correct cases (this
includes write_str_in_full(), which is just a wrapper for
write_in_full()).

[1] A careful reader may notice there is one way that
    write_in_full() can return a different value. If we ask
    write() to write N bytes and get a return value that is
    _larger_ than N, we could return a larger total. But
    besides the fact that this would imply a totally broken
    version of write(), it would already invoke undefined
    behavior. Our internal remaining counter is an unsigned
    size_t, which means that subtracting too many byte will
    wrap it around to a very large number. So we'll instantly
    begin reading off the end of the buffer, trying to write
    gigabytes (or petabytes) of data.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-14 15:17:59 +09:00
Junio C Hamano
6e96cb5286 rerere: allow approxidate in gc.rerereResolved/gc.rerereUnresolved
These two configuration variables are described in the documentation
to take an expiry period expressed in the number of days:

    gc.rerereResolved::
	    Records of conflicted merge you resolved earlier are
	    kept for this many days when 'git rerere gc' is run.
	    The default is 60 days.

    gc.rerereUnresolved::
	    Records of conflicted merge you have not resolved are
	    kept for this many days when 'git rerere gc' is run.
	    The default is 15 days.

There is no strong reason not to allow a more general "approxidate"
expiry specification, e.g. "5.days.ago", or "never".

Rename the config_get_expiry() helper introduced in the previous
step to git_config_get_expiry_in_days() and move it to a more
generic place, config.c, and use date.c::parse_expiry_date() to do
so.  Give it an ability to allow the caller to tell among three
cases (i.e. there is no "gc.rerereResolved" config, there is and it
is correctly parsed into the *expiry variable, and there was an
error in parsing the given value).  The current caller can work
correctly without using the return value, though.

In the future, we may find other variables that only allow an
integer that specifies "this many days" or other unit of time, and
when it happens we may need to drop "_days" suffix from the name of
the function and instead pass the "scale" value as another parameter.

But this will do for now.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-22 14:51:02 -07:00
Junio C Hamano
5ea82279c0 rerere: represent time duration in timestamp_t internally
The two configuration variables, gc.rerereResolved and
gc.rerereUnresolved, are measured in days and are passed as such
into the prune_one() helper function, which worked in time_t to see
if an entry in the rerere database is past its expiry.

Instead, have the caller turn the number of days into the expiry
timestamp.  Further, use timestamp_t instead of time_t.  This will
make it possible to extend the way the configuration variable is
spelled by using date.c::parse_expiry_date() that gives the expiry
timestamp in timestamp_t.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-22 14:51:02 -07:00
Junio C Hamano
50f03c6676 Merge branch 'ab/free-and-null'
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
2017-06-24 14:28:41 -07:00
Junio C Hamano
f31d23a399 Merge branch 'bw/config-h'
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
2017-06-24 14:28:41 -07:00
Ævar Arnfjörð Bjarmason
88ce3ef636 *.[ch] refactoring: make use of the FREE_AND_NULL() macro
Replace occurrences of `free(ptr); ptr = NULL` which weren't caught by
the coccinelle rule. These fall into two categories:

 - free/NULL assignments one after the other which coccinelle all put
   on one line, which is functionally equivalent code, but very ugly.

 - manually spotted occurrences where the NULL assignment isn't right
   after the free() call.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-16 12:44:09 -07:00
Brandon Williams
b2141fc1d2 config: don't include config.h by default
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>
2017-06-15 12:56:22 -07:00
Nguyễn Thái Ngọc Duy
f7566f073f rerere.c: move error_errno() closer to the source system call
We are supposed to report errno from fopen(). fclose() between fopen()
and the report function could either change errno or reset it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:33:56 +09:00
Nguyễn Thái Ngọc Duy
5118d7f4e6 print errno when reporting a system call error
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:33:56 +09:00
Nguyễn Thái Ngọc Duy
e9d983f116 wrapper.c: add and use fopen_or_warn()
When fopen() returns NULL, it could be because the given path does not
exist, but it could also be some other errors and the caller has to
check. Add a wrapper so we don't have to repeat the same error check
everywhere.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:33:56 +09:00
Junio C Hamano
b3e83cc752 hold_locked_index(): align error handling with hold_lockfile_for_update()
Callers of the hold_locked_index() function pass 0 when they want to
prepare to write a new version of the index file without wishing to
die or emit an error message when the request fails (e.g. somebody
else already held the lock), and pass 1 when they want the call to
die upon failure.

This option is called LOCK_DIE_ON_ERROR by the underlying lockfile
API, and the hold_locked_index() function translates the paramter to
LOCK_DIE_ON_ERROR when calling the hold_lock_file_for_update().

Replace these hardcoded '1' with LOCK_DIE_ON_ERROR and stop
translating.  Callers other than the ones that are replaced with
this change pass '0' to the function; no behaviour change is
intended with this patch.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

Among the callers of hold_locked_index() that passes 0:

 - diff.c::refresh_index_quietly() at the end of "git diff" is an
   opportunistic update; it leaks the lockfile structure but it is
   just before the program exits and nobody should care.

 - builtin/describe.c::cmd_describe(),
   builtin/commit.c::cmd_status(),
   sequencer.c::read_and_refresh_cache() are all opportunistic
   updates and they are OK.

 - builtin/update-index.c::cmd_update_index() takes a lock upfront
   but we may end up not needing to update the index (i.e. the
   entries may be fully up-to-date), in which case we do not need to
   issue an error upon failure to acquire the lock.  We do diagnose
   and die if we indeed need to update, so it is OK.

 - wt-status.c::require_clean_work_tree() IS BUGGY.  It asks
   silence, does not check the returned value.  Compare with
   callsites like cmd_describe() and cmd_status() to notice that it
   is wrong to call update_index_if_able() unconditionally.
2016-12-07 11:31:59 -08:00
brian m. carlson
99d1a9861a cache: convert struct cache_entry to use struct object_id
Convert struct cache_entry to use struct object_id by applying the
following semantic patch and the object_id transforms from contrib, plus
the actual change to the struct:

@@
struct cache_entry E1;
@@
- E1.sha1
+ E1.oid.hash

@@
struct cache_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>
2016-09-07 12:59:42 -07:00
Junio C Hamano
ec34a8b135 Merge branch 'jc/rerere-multi'
* jc/rerere-multi:
  rerere: remove an null statement
  rerere: plug memory leaks upon "rerere forget" failure
2016-05-23 14:54:38 -07:00
Junio C Hamano
d9d501b068 rerere: remove an null statement
J6t spotted that previous commit added an empty statement by
mistake.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-19 12:51:22 -07:00
Junio C Hamano
40cfc95856 Merge branch 'nd/error-errno'
The code for warning_errno/die_errno has been refactored and a new
error_errno() reporting helper is introduced.

* nd/error-errno: (41 commits)
  wrapper.c: use warning_errno()
  vcs-svn: use error_errno()
  upload-pack.c: use error_errno()
  unpack-trees.c: use error_errno()
  transport-helper.c: use error_errno()
  sha1_file.c: use {error,die,warning}_errno()
  server-info.c: use error_errno()
  sequencer.c: use error_errno()
  run-command.c: use error_errno()
  rerere.c: use error_errno() and warning_errno()
  reachable.c: use error_errno()
  mailmap.c: use error_errno()
  ident.c: use warning_errno()
  http.c: use error_errno() and warning_errno()
  grep.c: use error_errno()
  gpg-interface.c: use error_errno()
  fast-import.c: use error_errno()
  entry.c: use error_errno()
  editor.c: use error_errno()
  diff-no-index.c: use error_errno()
  ...
2016-05-17 14:38:28 -07:00
Junio C Hamano
8f4496148b rerere: plug memory leaks upon "rerere forget" failure
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-11 16:25:32 -07:00
Nguyễn Thái Ngọc Duy
033e011e64 rerere.c: use error_errno() and warning_errno()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-09 12:29:08 -07:00
Junio C Hamano
5b715ec48f Merge branch 'jc/rerere-multi'
"git rerere" can encounter two or more files with the same conflict
signature that have to be resolved in different ways, but there was
no way to record these separate resolutions.

* jc/rerere-multi:
  rerere: adjust 'forget' to multi-variant world order
  rerere: split code to call ll_merge() further
  rerere: move code related to "forget" together
  rerere: gc and clear
  rerere: do use multiple variants
  t4200: rerere a merge with two identical conflicts
  rerere: allow multiple variants to exist
  rerere: delay the recording of preimage
  rerere: handle leftover rr-cache/$ID directory and postimage files
  rerere: scan $GIT_DIR/rr-cache/$ID when instantiating a rerere_id
  rerere: split conflict ID further
2016-04-25 15:17:15 -07:00
Junio C Hamano
890fca84be rerere: adjust 'forget' to multi-variant world order
Because conflicts with the same contents inside conflict blocks
enclosed by "<<<<<<<" and ">>>>>>>" can now have multiple variants
to help three-way merge to adjust to the differences outside the
conflict blocks, "rerere forget $path" needs to be taught that there
may be multiple recorded resolutions that share the same conflict
hash (which groups the conflicts with "the same contents inside
conflict blocks"), among which there are some that would not be
relevant to the conflict we are looking at.  These "other variants"
that happen to share the same conflict hash should not be cleared,
and the variant that would apply to the current conflict may not be
the zero-th one (which is the only one that is cleared by the
current code).

After finding the conflict hash, iterate over the existing variants
and try to resolve the conflict using each of them to find the one
that "cleanly" resolves the current conflict.  That is the one we
want to forget and record the preimage for, so that the user can
record the corrected resolution.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-06 15:54:41 -07:00
Junio C Hamano
0ce02b3620 rerere: split code to call ll_merge() further
The merge() helper function is given an existing rerere ID (i.e. the
name of the .git/rr-cache/* subdirectory, and the variant number)
that identifies one <preimage, postimage> pair, try to see if the
conflicted state in the given path can be resolved by using the pair,
and if this succeeds, then update the conflicted path with the
result in the working tree.

To implement rerere_forget() in the multiple variant world, we'd
need a helper to do the "see if a <preimage, postimage> pair cleanly
resolves a conflicted state we have in-core" part, without actually
touching any file in the working tree, in order to identify which
variant(s) to remove.  Split the logic to do so into a separate
helper function try_merge() out of merge().

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-06 15:52:40 -07:00