Commit Graph

49220 Commits

Author SHA1 Message Date
Junio C Hamano
98c03a0de8 Merge branch 'tg/memfixes'
Fixes for a handful memory access issues identified by valgrind.

* tg/memfixes:
  sub-process: use child_process.args instead of child_process.argv
  http-push: fix construction of hex value from path
  path.c: fix uninitialized memory access
2017-10-07 16:27:54 +09:00
Junio C Hamano
cfa0fd0ffc Merge branch 'sb/branch-avoid-repeated-strbuf-release'
* sb/branch-avoid-repeated-strbuf-release:
  branch: reset instead of release a strbuf
2017-10-07 16:27:54 +09:00
Junio C Hamano
bd40f41b7b Merge branch 'rs/qsort-s'
* rs/qsort-s:
  test-stringlist: avoid buffer underrun when sorting nothing
2017-10-07 16:27:53 +09:00
Junio C Hamano
aae4788eee Merge branch 'jn/strbuf-doc-re-reuse'
* jn/strbuf-doc-re-reuse:
  strbuf doc: reuse after strbuf_release is fine
2017-10-07 16:27:53 +09:00
Junio C Hamano
436b35942c Merge branch 'tb/delimit-pretty-trailers-args-with-comma'
The feature that allows --pretty='%(trailers)' to take modifiers
like "fold" and "only" used to separate these modifiers with a
comma, i.e. "%(trailers:fold:only)", but we changed our mind and
use a comma, i.e. "%(trailers:fold,only)".  Fast track this change
before this new feature becomes part of any official release.

* tb/delimit-pretty-trailers-args-with-comma:
  pretty.c: delimit "%(trailers)" arguments with ","
2017-10-07 16:27:52 +09:00
Thomas Braun
7823655082 completion: add --broken and --dirty to describe
When the flags for broken and dirty were implemented in
b0176ce6b5 (builtin/describe: introduce --broken flag, 2017-03-21)
and 9f67d2e827 (Teach "git describe" --dirty option, 2009-10-21)
the completion was not updated, although these flags are useful
completions. Add them.

Signed-off-by: Thomas Braun <thomas.braun@virtuell-zuhause.de>
Helped-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-07 11:12:58 +09:00
Stefan Beller
9c5b2fab30 tests: fix diff order arguments in test_cmp
Fix the argument order for test_cmp. When given the expected
result first the diff shows the actual output with '+' and the
expectation with '-', which is the convention for our tests.

Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-07 10:56:08 +09:00
Jeff King
a1c1d8170d refs_resolve_ref_unsafe: handle d/f conflicts for writes
If our call to refs_read_raw_ref() fails, we check errno to
see if the ref is simply missing, or if we encountered a
more serious error. If it's just missing, then in "write"
mode (i.e., when RESOLVE_REFS_READING is not set), this is
perfectly fine.

However, checking for ENOENT isn't sufficient to catch all
missing-ref cases. In the filesystem backend, we may also
see EISDIR when we try to resolve "a" and "a/b" exists.
Likewise, we may see ENOTDIR if we try to resolve "a/b" and
"a" exists. In both of those cases, we know that our
resolved ref doesn't exist, but we return an error (rather
than reporting the refname and returning a null sha1).

This has been broken for a long time, but nobody really
noticed because the next step after resolving without the
READING flag is usually to lock the ref and write it. But in
both of those cases, the write will fail with the same
errno due to the directory/file conflict.

There are two cases where we can notice this, though:

  1. If we try to write "a" and there's a leftover directory
     already at "a", even though there is no ref "a/b". The
     actual write is smart enough to move the empty "a" out
     of the way.

     This is reasonably rare, if only because the writing
     code has to do an independent resolution before trying
     its write (because the actual update_ref() code handles
     this case fine). The notes-merge code does this, and
     before the fix in the prior commit t3308 erroneously
     expected this case to fail.

  2. When resolving symbolic refs, we typically do not use
     the READING flag because we want to resolve even
     symrefs that point to unborn refs. Even if those unborn
     refs could not actually be written because of d/f
     conflicts with existing refs.

     You can see this by asking "git symbolic-ref" to report
     the target of a symref pointing past a d/f conflict.

We can fix the problem by recognizing the other "missing"
errnos and treating them like ENOENT. This should be safe to
do even for callers who are then going to actually write the
ref, because the actual writing process will fail if the d/f
conflict is a real one (and t1404 checks these cases).

Arguably this should be the responsibility of the
files-backend to normalize all "missing ref" errors into
ENOENT (since something like EISDIR may not be meaningful at
all to a database backend). However other callers of
refs_read_raw_ref() may actually care about the distinction;
putting this into resolve_ref() is the minimal fix for now.

The new tests in t1401 use git-symbolic-ref, which is the
most direct way to check the resolution by itself.
Interestingly we actually had a test that setup this case
already, but we only used it to verify that the funny state
could be overwritten, not that it could be resolved.

We also add a new test in t3200, as "branch -m" was the
original motivation for looking into this. What happens is
this:

  0. HEAD is pointing to branch "a"

  1. The user asks to rename "a" to "a/b".

  2. We create "a/b" and delete "a".

  3. We then try to update any worktree HEADs that point to
     the renamed ref (including the main repo HEAD). To do
     that, we have to resolve each HEAD. But now our HEAD is
     pointing at "a", and we get EISDIR due to the loose
     "a/b". As a result, we think there is no HEAD, and we
     do not update it. It now points to the bogus "a".

Interestingly this case used to work, but only accidentally.
Before 31824d180d (branch: fix branch renaming not updating
HEADs correctly, 2017-08-24), we'd update any HEAD which we
couldn't resolve. That was wrong, but it papered over the
fact that we were incorrectly failing to resolve HEAD.

So while the bug demonstrated by the git-symbolic-ref is
quite old, the regression to "branch -m" is recent.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-07 10:32:13 +09:00
Jeff King
f2515d919e t3308: create a real ref directory/file conflict
A test in t3308 wants to make sure that we don't
accidentally merge into "refs/notes/dir" when it exists as a
directory, so it does:

  mkdir .git/refs/notes/dir
  git -c core.notesRef=refs/notes/dir merge ...

and expects the second command to fail. But that
understimates the refs code, which is smart enough to remove
useless directories in the refs hierarchy. The test
succeeded only because of a bug which prevented resolving
refs/notes/dir for writing, even though an actual ref update
would succeed.

In preparation for fixing that bug, let's switch to creating
a real ref in refs/notes/dir, which is a more realistic
situation.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-07 10:31:52 +09:00
Martin Ågren
b74c90fb41 read_cache: roll back lock in update_index_if_able()
`update_index_if_able()` used to always commit the lock or roll it back.
Commit 03b866477 (read-cache: new API write_locked_index instead of
write_index/write_cache, 2014-06-13) stopped rolling it back in case a
write was not even attempted. This change in behavior is not motivated
in the commit message and appears to be accidental: the `else`-path was
removed, although that changed the behavior in case the `if` shortcuts.

Reintroduce the rollback and document this behavior. While at it, move
the documentation on this function from the function definition to the
function declaration in cache.h.

If `write_locked_index(..., COMMIT_LOCK)` fails, it will roll back the
lock for us (see the previous commit).

Noticed-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-07 10:20:56 +09:00
Martin Ågren
df60cf5789 read-cache: leave lock in right state in write_locked_index()
If the original version of `write_locked_index()` returned with an
error, it didn't roll back the lockfile unless the error occured at the
very end, during closing/committing. See commit 03b866477 (read-cache:
new API write_locked_index instead of write_index/write_cache,
2014-06-13).

In commit 9f41c7a6b (read-cache: close index.lock in do_write_index,
2017-04-26), we learned to close the lock slightly earlier in the
callstack. That was mostly a side-effect of lockfiles being implemented
using temporary files, but didn't cause any real harm.

Recently, commit 076aa2cbd (tempfile: auto-allocate tempfiles on heap,
2017-09-05) introduced a subtle bug. If the temporary file is deleted
(i.e., the lockfile is rolled back), the tempfile-pointer in the `struct
lock_file` will be left dangling. Thus, an attempt to reuse the
lockfile, or even just to roll it back, will induce undefined behavior
-- most likely a crash.

Besides not crashing, we clearly want to make things consistent. The
guarantees which the lockfile-machinery itself provides is A) if we ask
to commit and it fails, roll back, and B) if we ask to close and it
fails, do _not_ roll back. Let's do the same for consistency.

Do not delete the temporary file in `do_write_index()`. One of its
callers, `write_locked_index()` will thereby avoid rolling back the
lock. The other caller, `write_shared_index()`, will delete its
temporary file anyway. Both of these callers will avoid undefined
behavior (crashing).

Teach `write_locked_index(..., COMMIT_LOCK)` to roll back the lock
before returning. If we have already succeeded and committed, it will be
a noop. Simplify the existing callers where we now have a superfluous
call to `rollback_lockfile()`. That should keep future readers from
wondering why the callers are inconsistent.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-07 10:20:56 +09:00
Martin Ågren
812d6b0075 read-cache: drop explicit CLOSE_LOCK-flag
`write_locked_index()` takes two flags: `COMMIT_LOCK` and `CLOSE_LOCK`.
At most one is allowed. But it is also possible to use no flag, i.e.,
`0`. But when `write_locked_index()` calls `do_write_index()`, the
temporary file, a.k.a. the lockfile, will be closed. So passing `0` is
effectively the same as `CLOSE_LOCK`, which seems like a bug.

We might feel tempted to restructure the code in order to close the file
later, or conditionally. It also feels a bit unfortunate that we simply
"happen" to close the lock by way of an implementation detail of
lockfiles. But note that we need to close the temporary file before
`stat`-ing it, at least on Windows. See 9f41c7a6b (read-cache: close
index.lock in do_write_index, 2017-04-26).

Drop `CLOSE_LOCK` and make it explicit that `write_locked_index()`
always closes the lock. Whether it is also committed is governed by the
remaining flag, `COMMIT_LOCK`.

This means we neither have nor suggest that we have a mode to write the
index and leave the file open. Whatever extra contents we might
eventually want to write, we should probably write it from within
`write_locked_index()` itself anyway.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-07 10:20:56 +09:00
Todd Zullinger
204f6d6987 api-argv-array.txt: remove broken link to string-list API
In 4f665f2cf3 (string-list.h: move documentation from Documentation/api/
into header, 2017-09-26) the string-list API documentation was moved to
string-list.h.  The argv-array API documentation may follow a similar
course in the future.  Until then, prevent the broken link from making
it to the end-user documentation.

Signed-off-by: Todd Zullinger <tmz@pobox.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 21:16:03 +09:00
Lars Schneider
11179eb311 entry.c: check if file exists after checkout
If we are checking out a file and somebody else racily deletes our file,
then we would write garbage to the cache entry. Fix that by checking
the result of the lstat() call on that file. Print an error to the user
if the file does not exist.

Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 14:59:16 +09:00
Jeff King
b3ea7dd32d sha1_loose_object_info: handle errors from unpack_sha1_rest
When a caller of sha1_object_info_extended() sets the
"contentp" field in object_info, we call unpack_sha1_rest()
but do not check whether it signaled an error.

This causes two problems:

  1. We pass back NULL to the caller via the contentp field,
     but the function returns "0" for success. A caller
     might reasonably expect after a successful return that
     it can access contentp without a NULL check and
     segfault.

     As it happens, this is impossible to trigger in the
     current code. There is exactly one caller which uses
     contentp, read_object(). And the only thing it does
     after a successful call is to return the content
     pointer to its caller, using NULL as a sentinel for
     errors. So in effect it converts the success code from
     sha1_object_info_extended() back into an error!

     But this is still worth addressing avoid problems for
     future users of "contentp".

  2. Callers of unpack_sha1_rest() are expected to close the
     zlib stream themselves on error. Which means that we're
     leaking the stream.

The problem in (1) comes from from c84a1f3ed4 (sha1_file:
refactor read_object, 2017-06-21), which added the contentp
field.  Before that, we called unpack_sha1_rest() via
unpack_sha1_file(), which directly used the NULL to signal
an error.

But note that the leak in (2) is actually older than that.
The original unpack_sha1_file() directly returned the result
of unpack_sha1_rest() to its caller, when it should have
been closing the zlib stream itself on error.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 13:04:41 +09:00
René Scharfe
99b7b687a6 .mailmap: normalize name for René Scharfe
Reported-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reported-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 11:31:41 +09:00
René Scharfe
2720f6db5d fsck: handle NULL return of lookup_blob() and lookup_tree()
lookup_blob() and lookup_tree() can return NULL if they find an object
of an unexpected type.  Accessing the object member is undefined in that
case.  Cast the result to a struct object pointer instead; we can do
that because object is the first member of all object types.  This trick
is already used in other places in the code.

An error message is already shown by object_as_type(), which is called
by the lookup functions.  The walk callback functions are expected to
handle NULL object pointers passed to them, but put_object_name() needs
a valid object, so avoid calling it without one.

Suggested-by: SZEDER Gábor <szeder.dev@gmail.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 11:04:34 +09:00
Martin Ågren
8dc3834610 cache.h: document write_locked_index()
The next patches will tweak the behavior of this function. Document it
in order to establish a basis for those patches.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:18 +09:00
Martin Ågren
d13cd4c927 apply: remove newfd from struct apply_state
Similar to a previous patch, we do not need to use `newfd` to signal
that we have a lockfile to clean up. We can just unconditionally call
`rollback_lock_file`. If we do not hold the lock, it will be a no-op.

Where we check `newfd` to decide whether we need to take the lock, we
can instead use `is_lock_file_locked()`.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:18 +09:00
Martin Ågren
6d058c8826 apply: move lockfile into apply_state
We have two users of `struct apply_state` and the related functionality
in apply.c. Each user sets up its `apply_state` by handing over a
pointer to its static `lock_file`. (Before 076aa2cbd (tempfile:
auto-allocate tempfiles on heap, 2017-09-05), we could never free
lockfiles, so making them static was a reasonable approach.)

Other than that, they never directly access their `lock_file`s, which
are instead handled by the functionality in apply.c.

To make life easier for the caller and to make it less tempting for a
future caller to mess with the lock, make apply.c fully responsible for
setting up the `lock_file`. As mentioned above, it is now safe to free a
`lock_file`, so we can make the `struct apply_state` contain an actual
`struct lock_file` instead of a pointer to one.

The user in builtin/apply.c is rather simple. For builtin/am.c, we might
worry that the lock state is actually meant to be inherited across
calls. But the lock is only taken as `apply_all_patches()` executes, and
code inspection shows that it will always be released.

Alternatively, we can observe that the lock itself is never queried
directly. When we decide whether we should lock, we check a related
variable `newfd`. That variable is not inherited, so from the point of
view of apply.c, the state machine really is reset with each call to
`init_apply_state()`. (It would be a bug if `newfd` and the lock status
were not in sync. The duplication of information in `newfd` and the lock
will be addressed in the next patch.)

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:18 +09:00
Martin Ågren
2954e5ec43 cache-tree: simplify locking logic
After we have taken the lock using `LOCK_DIE_ON_ERROR`, we know that
`newfd` is non-negative. So when we check for exactly that property
before calling `write_locked_index()`, the outcome is guaranteed.

If we write and commit successfully, we set `newfd = -1`, so that we can
later avoid calling `rollback_lock_file` on an already-committed lock.
But we might just as well unconditionally call `rollback_lock_file()` --
it will be a no-op if we have already committed.

All in all, we use `newfd` as a bool and the only benefit we get from it
is that we can avoid calling a no-op. Remove `newfd` so that we have one
variable less to reason about.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:18 +09:00
Martin Ågren
02ae242fdd checkout-index: simplify locking logic
`newfd` starts out negative. If we then take the lock, `newfd` will
become non-negative. We later check for exactly that property before
calling `write_locked_index()`. That is, we are simply using `newfd` as
a boolean to keep track of whether we took the lock or not. (We always
use `newfd` and `lock_file` together, so they really are mirroring each
other.)

Drop `newfd` and check with `is_lock_file_locked()` instead. While at
it, move the `static struct lock_file` into `cmd_checkout_index()` and
make it non-static. It is only used in this function, and after
076aa2cbd (tempfile: auto-allocate tempfiles on heap, 2017-09-05), we
can have lockfiles on the stack.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:18 +09:00
Martin Ågren
5de134ca85 tempfile: fix documentation on delete_tempfile()
The function has always been documented as returning 0 or -1. It is in
fact `void`. Correct that. As part of the rearrangements we lose the
mention that `delete_tempfile()` might set `errno`. Because there is
no return value, the user can't really know whether it did anyway.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:18 +09:00
Martin Ågren
d613576dfe lockfile: fix documentation on close_lock_file_gently()
Commit 83a3069a3 (lockfile: do not rollback lock on failed close,
2017-09-05) forgot to update the documentation by the function definition
to reflect that the lock is not rolled back in case closing fails.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:17 +09:00
Martin Ågren
837e34eba4 treewide: prefer lockfiles on the stack
There is no longer any need to allocate and leak a `struct lock_file`.
The previous patch addressed an instance where we needed a minor tweak
alongside the trivial changes.

Deal with the remaining instances where we allocate and leak a struct
within a single function. Change them to have the `struct lock_file` on
the stack instead.

These instances were identified by running `git grep "^\s*struct
lock_file\s*\*"`.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:17 +09:00
Martin Ågren
f132a127ee sha1_file: do not leak lock_file
There is no longer any need to allocate and leak a `struct lock_file`.
Initialize it on the stack instead.

Before this patch, we set `lock = NULL` to signal that we have already
rolled back, and that we should not do any more work. We need to take
another approach now that we cannot assign NULL. We could, e.g., use
`is_lock_file_locked()`. But we already have another variable that we
could use instead, `found`. Its scope is only too small.

Bump `found` to the scope of the whole function and rearrange the "roll
back or write?"-checks to a straightforward if-else on `found`. This
also future-proves the code by making it obvious that we intend to take
exactly one of these paths.

Improved-by: Jeff King <peff@peff.net>
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-06 10:07:10 +09:00
Lars Schneider
03b95333db entry.c: update cache entry only for existing files
In 2841e8f ("convert: add "status=delayed" to filter process protocol",
2017-06-30) we taught the filter process protocol to delay responses.

That means an external filter might answer in the first write_entry()
call on a file that requires filtering  "I got your request, but I
can't answer right now. Ask again later!". As Git got no answer, we do
not write anything to the filesystem. Consequently, the lstat() call in
the finish block of the function writes garbage to the cache entry.
The garbage is eventually overwritten when the filter answers with
the final file content in a subsequent write_entry() call.

Fix the brief time window of garbage in the cache entry by adding a
special finish block that does nothing for delayed responses. The cache
entry is written properly in a subsequent write_entry() call where
the filter responds with the final file content.

Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-05 20:01:07 +09:00
Junio C Hamano
217f2767cb Git 2.15-rc0
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-05 13:49:07 +09:00
Junio C Hamano
af66399510 Merge branch 'ar/request-pull-phrasofix'
Spell the name of our system as "Git" in the output from
request-pull script.

* ar/request-pull-phrasofix:
  request-pull: capitalise "Git" to make it a proper noun
2017-10-05 13:48:21 +09:00
Junio C Hamano
d5d5295e0a Merge branch 'rs/run-command-use-alloc-array'
Code clean-up.

* rs/run-command-use-alloc-array:
  run-command: use ALLOC_ARRAY
2017-10-05 13:48:20 +09:00
Junio C Hamano
6551e69fd4 Merge branch 'sb/git-clang-format'
Add comment to clarify that the style file is meant to be used with
clang-5 and the rules are still work in progress.

* sb/git-clang-format:
  clang-format: add a comment about the meaning/status of the
2017-10-05 13:48:20 +09:00
Junio C Hamano
e3c677fdc4 Merge branch 'rs/use-free-and-null'
Code clean-up.

* rs/use-free-and-null:
  repository: use FREE_AND_NULL
2017-10-05 13:48:20 +09:00
Junio C Hamano
1d4a1f6452 Merge branch 'rs/tag-null-pointer-arith-fix'
Code clean-up.

* rs/tag-null-pointer-arith-fix:
  tag: avoid NULL pointer arithmetic
2017-10-05 13:48:20 +09:00
Junio C Hamano
ac67aa5fd0 Merge branch 'rs/cocci-de-paren-call-params'
Code clean-up.

* rs/cocci-de-paren-call-params:
  coccinelle: remove parentheses that become unnecessary
2017-10-05 13:48:19 +09:00
Junio C Hamano
e46ebc2754 Merge branch 'rs/cleanup-strbuf-users'
Code clean-up.

* rs/cleanup-strbuf-users:
  graph: use strbuf_addchars() to add spaces
  use strbuf_addstr() for adding strings to strbufs
  path: use strbuf_add_real_path()
2017-10-05 13:48:19 +09:00
Junio C Hamano
efe9d6ce33 Merge branch 'rs/resolve-ref-optional-result'
Code clean-up.

* rs/resolve-ref-optional-result:
  refs: pass NULL to resolve_refdup() if hash is not needed
  refs: pass NULL to refs_resolve_refdup() if hash is not needed
2017-10-05 13:48:19 +09:00
Junio C Hamano
29a67ccc89 Merge branch 'er/fast-import-dump-refs-on-checkpoint'
The checkpoint command "git fast-import" did not flush updates to
refs and marks unless at least one object was created since the
last checkpoint, which has been corrected, as these things can
happen without any new object getting created.

* er/fast-import-dump-refs-on-checkpoint:
  fast-import: checkpoint: dump branches/tags/marks even if object_count==0
2017-10-05 13:48:19 +09:00
Taylor Blau
bea4dbeafd ref-filter.c: pass empty-string as NULL to atom parsers
Peff points out that different atom parsers handle the empty
"sub-argument" list differently. An example of this is the format
"%(refname:)".

Since callers often use `string_list_split` (which splits the empty
string with any delimiter as a 1-ary string_list containing the empty
string), this makes handling empty sub-argument strings non-ergonomic.

Let's fix this by declaring that atom parser implementations must
not care about distinguishing between the empty string "%(refname:)"
and no sub-arguments "%(refname)".  Current code aborts, either with
"unrecognised arg" (e.g. "refname:") or "does not take args"
(e.g. "body:") as an error message.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-05 10:41:57 +09:00
Jonathan Nieder
e0222159fa strbuf doc: reuse after strbuf_release is fine
strbuf_release leaves the strbuf in a valid, initialized state, so
there is no need to call strbuf_init after it.

Moreover, this is not likely to change in the future: strbuf_release
leaving the strbuf in a valid state has been easy to maintain and has
been very helpful for Git's robustness and simplicity (e.g.,
preventing use-after-free vulnerabilities).

Document the semantics so the next generation of Git developers can
become familiar with them without reading the implementation.  It is
still not advisable to call strbuf_release too often because it is
wasteful, so add a note pointing to strbuf_reset for that.

The same semantics apply to strbuf_detach.  Add a similar note to its
docstring to make that clear.

Improved-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 15:21:52 +09:00
Stefan Beller
a9155c50bd branch: reset instead of release a strbuf
Our documentation advises to not re-use a strbuf, after strbuf_release
has been called on it. Use the proper reset instead.

Currently 'strbuf_release' releases and re-initializes the strbuf, so it
is safe, but slow. 'strbuf_reset' only resets the internal length variable,
such that this could also be accounted for as a micro-optimization.

Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 15:21:31 +09:00
Johannes Sixt
2944a94c6b sub-process: use child_process.args instead of child_process.argv
Currently the argv is only allocated on the stack, and then assigned to
process->argv.  When the start_subprocess function goes out of scope,
the local argv variable is eliminated from the stack, but the pointer is
still kept around in process->argv.

Much later when we try to access the same process->argv in
finish_command, this leads us to access a memory location that no longer
contains what we want.  As argv0 is only used for printing errors, this
is not easily noticed in normal git operations.  However when running
t0021-conversion.sh through valgrind, valgrind rightfully complains:

==21024== Invalid read of size 8
==21024==    at 0x2ACF64: finish_command (run-command.c:869)
==21024==    by 0x2D6B18: subprocess_exit_handler (sub-process.c:72)
==21024==    by 0x2AB41E: cleanup_children (run-command.c:45)
==21024==    by 0x2AB526: cleanup_children_on_exit (run-command.c:81)
==21024==    by 0x54AD487: __run_exit_handlers (in /usr/lib/libc-2.26.so)
==21024==    by 0x54AD4D9: exit (in /usr/lib/libc-2.26.so)
==21024==    by 0x11A9EF: handle_builtin (git.c:550)
==21024==    by 0x11ABCC: run_argv (git.c:602)
==21024==    by 0x11AD8E: cmd_main (git.c:679)
==21024==    by 0x1BF125: main (common-main.c:43)
==21024==  Address 0x1ffeffec00 is on thread 1's stack
==21024==  1504 bytes below stack pointer
==21024==

These days, the child_process structure has its own args array, and
the standard way to set up its argv[] is to use that one, instead of
assigning to process->argv to point at an array that is outside.
Use that facility automatically fixes this issue.

Reported-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 13:58:15 +09:00
Thomas Gummerer
51bfb734df http-push: fix construction of hex value from path
The get_oid_hex_from_objpath takes care of creating a oid from a
pathname.  It does this by memcpy'ing the first two bytes of the path to
the "hex" string, then skipping the '/', and then copying the rest of the
path to the "hex" string.  Currently it fails to increase the pointer to
the hex string, so the second memcpy invocation just mashes over what
was copied in the first one, and leaves the last two bytes in the string
uninitialized.

This breaks valgrind in t5540, although the test passes without
valgrind:

==5490== Use of uninitialised value of size 8
==5490==    at 0x13C6B5: hexval (cache.h:1238)
==5490==    by 0x13C6DB: hex2chr (cache.h:1247)
==5490==    by 0x13C734: get_sha1_hex (hex.c:42)
==5490==    by 0x13C78E: get_oid_hex (hex.c:53)
==5490==    by 0x118BDA: get_oid_hex_from_objpath (http-push.c:1023)
==5490==    by 0x118C92: process_ls_object (http-push.c:1038)
==5490==    by 0x118E5B: handle_remote_ls_ctx (http-push.c:1077)
==5490==    by 0x118227: xml_end_tag (http-push.c:815)
==5490==    by 0x50C1448: ??? (in /usr/lib/libexpat.so.1.6.6)
==5490==    by 0x50C221B: ??? (in /usr/lib/libexpat.so.1.6.6)
==5490==    by 0x50BFBF2: ??? (in /usr/lib/libexpat.so.1.6.6)
==5490==    by 0x50C0B24: ??? (in /usr/lib/libexpat.so.1.6.6)
==5490==  Uninitialised value was created by a stack allocation
==5490==    at 0x118B63: get_oid_hex_from_objpath (http-push.c:1012)
==5490==

Fix this by correctly incrementing the pointer to the "hex" variable, so
the first two bytes are left untouched by the memcpy call, and the last
two bytes are correctly initialized.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 13:48:35 +09:00
Jeff King
8262715b8e path.c: fix uninitialized memory access
In cleanup_path we're passing in a char array, run a memcmp on it, and
run through it without ever checking if something is in the array in the
first place.  This can lead us to access uninitialized memory, for
example in t5541-http-push-smart.sh test 7, when run under valgrind:

==4423== Conditional jump or move depends on uninitialised value(s)
==4423==    at 0x242FA9: cleanup_path (path.c:35)
==4423==    by 0x242FA9: mkpath (path.c:456)
==4423==    by 0x256CC7: refname_match (refs.c:364)
==4423==    by 0x26C181: count_refspec_match (remote.c:1015)
==4423==    by 0x26C181: match_explicit_lhs (remote.c:1126)
==4423==    by 0x26C181: check_push_refs (remote.c:1409)
==4423==    by 0x2ABB4D: transport_push (transport.c:870)
==4423==    by 0x186703: push_with_options (push.c:332)
==4423==    by 0x18746D: do_push (push.c:409)
==4423==    by 0x18746D: cmd_push (push.c:566)
==4423==    by 0x1183E0: run_builtin (git.c:352)
==4423==    by 0x11973E: handle_builtin (git.c:539)
==4423==    by 0x11973E: run_argv (git.c:593)
==4423==    by 0x11973E: main (git.c:698)
==4423==  Uninitialised value was created by a heap allocation
==4423==    at 0x4C2CD8F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==4423==    by 0x4C2F195: realloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==4423==    by 0x2C196B: xrealloc (wrapper.c:137)
==4423==    by 0x29A30B: strbuf_grow (strbuf.c:66)
==4423==    by 0x29A30B: strbuf_vaddf (strbuf.c:277)
==4423==    by 0x242F9F: mkpath (path.c:454)
==4423==    by 0x256CC7: refname_match (refs.c:364)
==4423==    by 0x26C181: count_refspec_match (remote.c:1015)
==4423==    by 0x26C181: match_explicit_lhs (remote.c:1126)
==4423==    by 0x26C181: check_push_refs (remote.c:1409)
==4423==    by 0x2ABB4D: transport_push (transport.c:870)
==4423==    by 0x186703: push_with_options (push.c:332)
==4423==    by 0x18746D: do_push (push.c:409)
==4423==    by 0x18746D: cmd_push (push.c:566)
==4423==    by 0x1183E0: run_builtin (git.c:352)
==4423==    by 0x11973E: handle_builtin (git.c:539)
==4423==    by 0x11973E: run_argv (git.c:593)
==4423==    by 0x11973E: main (git.c:698)
==4423==

Avoid this by using skip_prefix(), which knows not to go beyond the
end of the string.

Reported-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 13:47:16 +09:00
René Scharfe
97487ea11a test-stringlist: avoid buffer underrun when sorting nothing
Check if the strbuf containing data to sort is empty before attempting
to trim a trailing newline character.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 13:41:49 +09:00
Kaartic Sivaraam
33f3c683ec setup: update error message to be more meaningful
The error message shown when a flag is found when expecting a
filename wasn't clear as it didn't communicate what was wrong
using the 'suitable' words in *all* cases.

        $ git ls-files
        README.md
        test-file

Correct case,

        $ git rev-parse README.md --flags
        README.md
        --flags
        fatal: bad flag '--flags' used after filename

Incorrect case,

        $ git grep "some random regex" -n
        fatal: bad flag '-n' used after filename

The above case is incorrect as "some random regex" isn't a filename
in this case.

Change the error message to be general and communicative. This results
in the following output,

        $ git rev-parse README.md --flags
        README.md
        --flags
        fatal: option '--flags' must come before non-option arguments

        $ git grep "some random regex" -n
        fatal: option '-n' must come before non-option arguments

Signed-off-by: Kaartic Sivaraam <kaarticsivaraam91196@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 13:13:02 +09:00
Kaartic Sivaraam
f777623514 branch: change the error messages to be more meaningful
The error messages shown when the branch command is misused
by supplying it wrong number of parameters wasn't meaningful.
That's because it used the the phrase "too many branches"
assuming all parameters to be "valid" branch names. It's not
always the case as exemplified below,

        $ git branch
          foo
        * master

        $ git branch -m foo foo old
        fatal: too many branches for a rename operation

Change the messages to be more general thus making no assumptions
about the "parameters".

Signed-off-by: Kaartic Sivaraam <kaarticsivaraam91196@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 13:08:17 +09:00
Junio C Hamano
aebd23506e Merge branch 'jk/ui-color-always-to-auto-maint' into jk/ui-color-always-to-auto
* jk/ui-color-always-to-auto-maint:
  color: make "always" the same as "auto" in config
  provide --color option for all ref-filter users
  t3205: use --color instead of color.branch=always
  t3203: drop "always" color test
  t6006: drop "always" color config tests
  t7502: use diff.noprefix for --verbose test
  t7508: use test_terminal for color output
  t3701: use test-terminal to collect color output
  t4015: prefer --color to -c color.diff=always
  test-terminal: set TERM=vt100
2017-10-04 12:04:47 +09:00
Jeff King
3c788e79b8 t7301: use test_terminal to check color
This test wants to confirm that "clean -i" shows color
output. Using test_terminal gives us a more realistic
environment than "color.ui=always", and prepares us for the
behavior of "always" changing in a future patch.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 11:49:31 +09:00
Jeff King
269c73e8d3 t4015: use --color with --color-moved
The tests for --color-moved write their output to a file,
but doing so suppresses color output under "auto". Right now
this is solved by running the whole script under
"color.diff=always". In preparation for the behavior of
"always" changing, let's explicitly enable color.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 11:48:17 +09:00
Jeff King
6be4595edb color: make "always" the same as "auto" in config
It can be handy to use `--color=always` (or it's synonym
`--color`) on the command-line to convince a command to
produce color even if it's stdout isn't going to the
terminal or a pager.

What's less clear is whether it makes sense to set config
variables like color.ui to `always`. For a one-shot like:

  git -c color.ui=always ...

it's potentially useful (especially if the command doesn't
directly support the `--color` option). But setting `always`
in your on-disk config is much muddier, as you may be
surprised when piped commands generate colors (and send them
to whatever is consuming the pipe downstream).

Some people have done this anyway, because:

  1. The documentation for color.ui makes it sound like
     using `always` is a good idea, when you almost
     certainly want `auto`.

  2. Traditionally not every command (and especially not
     plumbing) respected color.ui in the first place. So
     the confusion came up less frequently than it might
     have.

The situation changed in 136c8c8b8f (color: check color.ui
in git_default_config(), 2017-07-13), which negated point
(2): now scripts using only plumbing commands (like
add-interactive) are broken by this setting.

That commit was fixing real issues (e.g., by making
`color.ui=never` work, since `auto` is the default), so we
don't want to just revert it.  We could turn `always` into a
noop in plumbing commands, but that creates a hard-to-explain
inconsistency between the plumbing and other commands.

Instead, let's just turn `always` into `auto` for all config.
This does break the "one-shot" config shown above, but again,
we're probably better to have simple and consistent rules than
to try to special-case command-line config.

There is one place where `always` should retain its meaning:
on the command line, `--color=always` should continue to be
the same as `--color`, overriding any isatty checks. Since the
command-line parser also depends on git_config_colorbool(), we
can use the existence of the "var" string to deterine whether
we are serving the command-line or the config.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-04 11:35:30 +09:00