Commit Graph

730 Commits

Author SHA1 Message Date
Junio C Hamano
aa9136a87e Merge branch 'nd/pack-ofs-4gb-limit' into maint
"git pack-objects" and "git index-pack" mostly operate with off_t
when talking about the offset of objects in a packfile, but there
were a handful of places that used "unsigned long" to hold that
value, leading to an unintended truncation.

* nd/pack-ofs-4gb-limit:
  fsck: use streaming interface for large blobs in pack
  pack-objects: do not truncate result in-pack object size on 32-bit systems
  index-pack: correct "offset" type in unpack_entry_data()
  index-pack: report correct bad object offsets even if they are large
  index-pack: correct "len" type in unpack_data()
  sha1_file.c: use type off_t* for object_info->disk_sizep
  pack-objects: pass length to check_pack_crc() without truncation
2016-08-08 14:21:36 -07:00
Nguyễn Thái Ngọc Duy
211c61c6cf pack-objects: pass length to check_pack_crc() without truncation
On 32 bit systems with large file support, unsigned long is 32-bit
while the two offsets in the subtraction expression (pack-objects has
the exact same expression as in sha1_file.c but not shown in diff) are
in 64-bit. If an in-pack object is larger than 2^32 len/datalen is
truncated and we get a misleading "error: bad packed object CRC for
..." as a result.

Use off_t for len and datalen. check_pack_crc() already accepts this
argument as off_t and can deal with 4+ GB.

Noticed-by: Christoph Michelbach <michelbach94@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-12 10:14:29 -07:00
Junio C Hamano
352d72a30e Merge branch 'nd/worktree-various-heads'
The experimental "multiple worktree" feature gains more safety to
forbid operations on a branch that is checked out or being actively
worked on elsewhere, by noticing that e.g. it is being rebased.

* nd/worktree-various-heads:
  branch: do not rename a branch under bisect or rebase
  worktree.c: check whether branch is bisected in another worktree
  wt-status.c: split bisect detection out of wt_status_get_state()
  worktree.c: check whether branch is rebased in another worktree
  worktree.c: avoid referencing to worktrees[i] multiple times
  wt-status.c: make wt_status_check_rebase() work on any worktree
  wt-status.c: split rebase detection out of wt_status_get_state()
  path.c: refactor and add worktree_git_path()
  worktree.c: mark current worktree
  worktree.c: make find_shared_symref() return struct worktree *
  worktree.c: store "id" instead of "git_dir"
  path.c: add git_common_path() and strbuf_git_common_path()
  dir.c: rename str(n)cmp_icase to fspath(n)cmp
2016-05-23 14:54:29 -07:00
Nguyễn Thái Ngọc Duy
7616c6ca9d sha1_file.c: use {error,die,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
Nguyễn Thái Ngọc Duy
ba0897e6ae dir.c: rename str(n)cmp_icase to fspath(n)cmp
These functions compare two paths that are taken from file system.
Depending on the running file system, paths may need to be compared
case-sensitively or not, and maybe even something else in future. The
current names do not convey that well.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-22 14:09:37 -07:00
Junio C Hamano
090de6b289 Merge branch 'jk/pack-idx-corruption-safety'
The code to read the pack data using the offsets stored in the pack
idx file has been made more carefully check the validity of the
data in the idx.

* jk/pack-idx-corruption-safety:
  sha1_file.c: mark strings for translation
  use_pack: handle signed off_t overflow
  nth_packed_object_offset: bounds-check extended offset
  t5313: test bounds-checks of corrupted/malicious pack/idx files
2016-03-04 13:45:47 -08:00
Nguyễn Thái Ngọc Duy
7465feba51 sha1_file.c: mark strings for translation
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-27 09:54:57 -08:00
Junio C Hamano
11529ecec9 Merge branch 'jk/tighten-alloc'
Update various codepaths to avoid manually-counted malloc().

* jk/tighten-alloc: (22 commits)
  ewah: convert to REALLOC_ARRAY, etc
  convert ewah/bitmap code to use xmalloc
  diff_populate_gitlink: use a strbuf
  transport_anonymize_url: use xstrfmt
  git-compat-util: drop mempcpy compat code
  sequencer: simplify memory allocation of get_message
  test-path-utils: fix normalize_path_copy output buffer size
  fetch-pack: simplify add_sought_entry
  fast-import: simplify allocation in start_packfile
  write_untracked_extension: use FLEX_ALLOC helper
  prepare_{git,shell}_cmd: use argv_array
  use st_add and st_mult for allocation size computation
  convert trivial cases to FLEX_ARRAY macros
  use xmallocz to avoid size arithmetic
  convert trivial cases to ALLOC_ARRAY
  convert manual allocations to argv_array
  argv-array: add detach function
  add helpers for allocating flex-array structs
  harden REALLOC_ARRAY and xcalloc against size_t overflow
  tree-diff: catch integer overflow in combine_diff_path allocation
  ...
2016-02-26 13:37:16 -08:00
Jeff King
13e0b0d3dc use_pack: handle signed off_t overflow
A v2 pack index file can specify an offset within a packfile
of up to 2^64-1 bytes. On a system with a signed 64-bit
off_t, we can represent only up to 2^63-1. This means that a
corrupted .idx file can end up with a negative offset in the
pack code. Our bounds-checking use_pack function looks for
too-large offsets, but not for ones that have wrapped around
to negative. Let's do so, which fixes an out-of-bounds
access demonstrated in t5313.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 11:32:46 -08:00
Jeff King
47fe3f6ef0 nth_packed_object_offset: bounds-check extended offset
If a pack .idx file has a corrupted offset for an object, we
may try to access an offset in the .idx or .pack file that
is larger than the file's size.  For the .pack case, we have
use_pack() to protect us, which realizes the access is out
of bounds. But if the corrupted value asks us to look in the
.idx file's secondary 64-bit offset table, we blindly add it
to the mmap'd index data and access arbitrary memory.

We can fix this with a simple bounds-check compared to the
size we found when we opened the .idx file.

Note that there's similar code in index-pack that is
triggered only during "index-pack --verify". To support
both, we pull the bounds-check into a separate function,
which dies when it sees a corrupted file.

It would be nice if we could return an error, so that the
pack code could try to find a good copy of the object
elsewhere. Currently nth_packed_object_offset doesn't have
any way to return an error, but it could probably use "0" as
a sentinel value (since no object can start there). This is
the minimal fix, and we can improve the resilience later on
top.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 11:32:43 -08:00
Jeff King
50a6c8efa2 use st_add and st_mult for allocation size computation
If our size computation overflows size_t, we may allocate a
much smaller buffer than we expected and overflow it. It's
probably impossible to trigger an overflow in most of these
sites in practice, but it is easy enough convert their
additions and multiplications into overflow-checking
variants. This may be fixing real bugs, and it makes
auditing the code easier.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Jeff King
b32fa95fd8 convert trivial cases to ALLOC_ARRAY
Each of these cases can be converted to use ALLOC_ARRAY or
REALLOC_ARRAY, which has two advantages:

  1. It automatically checks the array-size multiplication
     for overflow.

  2. It always uses sizeof(*array) for the element-size,
     so that it can never go out of sync with the declared
     type of the array.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Junio C Hamano
3f16396228 clone/sha1_file: read info/alternates with strbuf_getline()
$GIT_OBJECT_DIRECTORY/info/alternates is a text file that can be
edited with a DOS editor.  We do not want to use the real path with
CR appended at the end.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-15 10:34:53 -08:00
Junio C Hamano
8f309aeb82 strbuf: introduce strbuf_getline_{lf,nul}()
The strbuf_getline() interface allows a byte other than LF or NUL as
the line terminator, but this is only because I wrote these
codepaths anticipating that there might be a value other than NUL
and LF that could be useful when I introduced line_termination long
time ago.  No useful caller that uses other value has emerged.

By now, it is clear that the interface is overly broad without a
good reason.  Many codepaths have hardcoded preference to read
either LF terminated or NUL terminated records from their input, and
then call strbuf_getline() with LF or NUL as the third parameter.

This step introduces two thin wrappers around strbuf_getline(),
namely, strbuf_getline_lf() and strbuf_getline_nul(), and
mechanically rewrites these call sites to call either one of
them.  The changes contained in this patch are:

 * introduction of these two functions in strbuf.[ch]

 * mechanical conversion of all callers to strbuf_getline() with
   either '\n' or '\0' as the third parameter to instead call the
   respective thin wrapper.

After this step, output from "git grep 'strbuf_getline('" would
become a lot smaller.  An interim goal of this series is to make
this an empty set, so that we can have strbuf_getline_crlf() take
over the shorter name strbuf_getline().

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-15 10:12:51 -08:00
Junio C Hamano
fbe959dde7 Merge branch 'bc/format-patch-null-from-line'
"format-patch" has learned a new option to zero-out the commit
object name on the mbox "From " line.

* bc/format-patch-null-from-line:
  format-patch: check that header line has expected format
  format-patch: add an option to suppress commit hash
  sha1_file.c: introduce a null_oid constant
2015-12-21 10:59:08 -08:00
Junio C Hamano
897b18508b Merge branch 'jk/prune-mtime'
The helper used to iterate over loose object directories to prune
stale objects did not closedir() immediately when it is done with a
directory--a callback such as the one used for "git prune" may want
to do rmdir(), but it would fail on open directory on platforms
such as WinXP.

* jk/prune-mtime:
  prune: close directory earlier during loose-object directory traversal
2015-12-15 08:02:16 -08:00
brian m. carlson
3e56e7245c sha1_file.c: introduce a null_oid constant
null_oid is the struct object_id equivalent to null_sha1.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-12-14 13:35:54 -08:00
brian m. carlson
b419aa25d5 sha1_file: introduce has_object_file helper.
Add has_object_file, which is a wrapper around has_sha1_file, but for
struct object_id.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
2015-11-20 08:02:05 -05:00
Jeff King
45014beac0 Merge branch 'dk/gc-idx-wo-pack'
Having a leftover .idx file without corresponding .pack file in
the repository hurts performance; "git gc" learned to prune them.

* dk/gc-idx-wo-pack:
  gc: remove garbage .idx files from pack dir
  t5304: test cleaning pack garbage
  prepare_packed_git(): refactor garbage reporting in pack directory
2015-11-20 06:55:34 -05:00
Junio C Hamano
808d119263 Merge branch 'js/misc-fixes'
Various compilation fixes and squelching of warnings.

* js/misc-fixes:
  Correct fscanf formatting string for I64u values
  Silence GCC's "cast of pointer to integer of a different size" warning
  Squelch warning about an integer overflow
2015-10-30 13:07:00 -07:00
Johannes Schindelin
56a1a3ab44 Silence GCC's "cast of pointer to integer of a different size" warning
When calculating hashes from pointers, it actually makes sense to cut
off the most significant bits. In that case, said warning does not make
a whole lot of sense.

So let's just work around it by casting the pointer first to intptr_t
and then casting up/down to the final integral type.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-26 13:24:03 -07:00
Junio C Hamano
78891795df Merge branch 'jk/war-on-sprintf'
Many allocations that is manually counted (correctly) that are
followed by strcpy/sprintf have been replaced with a less error
prone constructs such as xstrfmt.

Macintosh-specific breakage was noticed and corrected in this
reroll.

* jk/war-on-sprintf: (70 commits)
  name-rev: use strip_suffix to avoid magic numbers
  use strbuf_complete to conditionally append slash
  fsck: use for_each_loose_file_in_objdir
  Makefile: drop D_INO_IN_DIRENT build knob
  fsck: drop inode-sorting code
  convert strncpy to memcpy
  notes: document length of fanout path with a constant
  color: add color_set helper for copying raw colors
  prefer memcpy to strcpy
  help: clean up kfmclient munging
  receive-pack: simplify keep_arg computation
  avoid sprintf and strcpy with flex arrays
  use alloc_ref rather than hand-allocating "struct ref"
  color: add overflow checks for parsing colors
  drop strcpy in favor of raw sha1_to_hex
  use sha1_to_hex_r() instead of strcpy
  daemon: use cld->env_array when re-spawning
  stat_tracking_info: convert to argv_array
  http-push: use an argv_array for setup_revisions
  fetch-pack: use argv_array for index-pack / unpack-objects
  ...
2015-10-20 15:24:01 -07:00
Junio C Hamano
db5adf24bf Merge branch 'js/clone-dissociate'
"git clone --dissociate" runs a big "git repack" process at the
end, and it helps to close file descriptors that are open on the
packs and their idx files before doing so on filesystems that
cannot remove a file that is still open.

* js/clone-dissociate:
  clone --dissociate: avoid locking pack files
  sha1_file.c: add a function to release all packs
  sha1_file: consolidate code to close a pack's file descriptor
  t5700: demonstrate a Windows file locking issue with `git clone --dissociate`
2015-10-15 15:43:49 -07:00
Johannes Schindelin
38849a8116 sha1_file.c: add a function to release all packs
On Windows, files that are in use cannot be removed or renamed. That
means that we have to release pack files when we are about to, say,
repack them. Let's introduce a convenient function to close all the
pack files and their idx files.

While at it, we consolidate the close windows/close fd/close index
stanza in `free_pack_by_name()` into the `close_pack()` function that
is used by the new `close_all_packs()` function to avoid repeated code.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-07 10:47:10 -07:00
Johannes Schindelin
71fe5d7fb0 sha1_file: consolidate code to close a pack's file descriptor
There was a lot of repeated code to close the file descriptor of
a given pack. Let's just refactor this code into a single function.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05 14:43:58 -07:00
Jeff King
c7ab0ba340 avoid sprintf and strcpy with flex arrays
When we are allocating a struct with a FLEX_ARRAY member, we
generally compute the size of the array and then sprintf or
strcpy into it. Normally we could improve a dynamic allocation
like this by using xstrfmt, but it doesn't work here; we
have to account for the size of the rest of the struct.

But we can improve things a bit by storing the length that
we use for the allocation, and then feeding it to xsnprintf
or memcpy, which makes it more obvious that we are not
writing more than the allocated number of bytes.

It would be nice if we had some kind of helper for
allocating generic flex arrays, but it doesn't work that
well:

 - the call signature is a little bit unwieldy:

      d = flex_struct(sizeof(*d), offsetof(d, path), fmt, ...);

   You need offsetof here instead of just writing to the
   end of the base size, because we don't know how the
   struct is packed (partially this is because FLEX_ARRAY
   might not be zero, though we can account for that; but
   the size of the struct may actually be rounded up for
   alignment, and we can't know that).

 - some sites do clever things, like over-allocating because
   they know they will write larger things into the buffer
   later (e.g., struct packed_git here).

So we're better off to just write out each allocation (or
add type-specific helpers, though many of these are one-off
allocations anyway).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05 11:08:05 -07:00
Jeff King
d4b3d11a03 write_loose_object: convert to strbuf
When creating a loose object tempfile, we use a fixed
PATH_MAX-sized buffer, and strcpy directly into it. This
isn't buggy, because we do a rough check of the size, but
there's no verification that our guesstimate of the required
space is enough (in fact, it's several bytes too big for the
current naming scheme).

Let's switch to a strbuf, which makes this much easier to
verify. The allocation overhead should be negligible, since
we are replacing a static buffer with a static strbuf, and
we'll only need to allocate on the first call.

While we're here, we can also document a subtle interaction
with mkstemp that would be easy to overlook.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05 11:08:05 -07:00
Jeff King
ac5190cc48 sha1_get_pack_name: use a strbuf
We do some manual memory computation here, and there's no
check that our 60 is not overflowed by the raw sprintf (it
isn't, because the "which" parameter is never longer than
"pack"). We can simplify this greatly with a strbuf.

Technically the end result is not identical, as the original
took care not to rewrite the object directory on each call
for performance reasons.  We could do that here, too (by
saving the baselen and resetting to it), but it's not worth
the complexity; this function is not called a lot (generally
once per packfile that we open).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25 10:18:18 -07:00
Jeff King
9ae97018fb use strip_suffix and xstrfmt to replace suffix
When we want to convert "foo.pack" to "foo.idx", we do it by
duplicating the original string and then munging the bytes
in place. Let's use strip_suffix and xstrfmt instead, which
has several advantages:

  1. It's more clear what the intent is.

  2. It does not implicitly rely on the fact that
     strlen(".idx") <= strlen(".pack") to avoid an overflow.

  3. We communicate the assumption that the input file ends
     with ".pack" (and get a run-time check that this is so).

  4. We drop calls to strcpy, which makes auditing the code
     base easier.

Likewise, we can do this to convert ".pack" to ".bitmap",
avoiding some manual memory computation.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25 10:18:18 -07:00
Jeff King
48bcc1c3cc add_packed_git: convert strcpy into xsnprintf
We have the path "foo.idx", and we create a buffer big
enough to hold "foo.pack" and "foo.keep", and then strcpy
straight into it. This isn't a bug (we have enough space),
but it's very hard to tell from the strcpy that this is so.

Let's instead use strip_suffix to take off the ".idx",
record the size of our allocation, and use xsnprintf to make
sure we don't violate our assumptions.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25 10:18:18 -07:00
Jeff King
ef1286d3c0 use xsnprintf for generating git object headers
We generally use 32-byte buffers to format git's "type size"
header fields. These should not generally overflow unless
you can produce some truly gigantic objects (and our types
come from our internal array of constant strings). But it is
a good idea to use xsnprintf to make sure this is the case.

Note that we slightly modify the interface to
write_sha1_file_prepare, which nows uses "hdrlen" as an "in"
parameter as well as an "out" (on the way in it stores the
allocated size of the header, and on the way out it returns
the ultimate size of the header).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25 10:18:18 -07:00
Junio C Hamano
f0bc854623 Sync with 2.5.2 2015-09-09 14:30:35 -07:00
Junio C Hamano
3d3caf0b78 Sync with 2.4.9 2015-09-04 10:43:23 -07:00
Junio C Hamano
ef0e938a1a Sync with 2.3.9 2015-09-04 10:34:19 -07:00
Junio C Hamano
8267cd11d6 Sync with 2.2.3 2015-09-04 10:29:28 -07:00
Jeff King
5015f01c12 read_info_alternates: handle paths larger than PATH_MAX
This function assumes that the relative_base path passed
into it is no larger than PATH_MAX, and writes into a
fixed-size buffer. However, this path may not have actually
come from the filesystem; for example, add_submodule_odb
generates a path using a strbuf and passes it in. This is
hard to trigger in practice, though, because the long
submodule directory would have to exist on disk before we
would try to open its info/alternates file.

We can easily avoid the bug, though, by simply creating the
filename on the heap.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-04 09:36:51 -07:00
Junio C Hamano
cbcd3dcaa8 Merge branch 'cb/open-noatime-clear-errno' into maint
When trying to see that an object does not exist, a state errno
leaked from our "first try to open a packfile with O_NOATIME and
then if it fails retry without it" logic on a system that refuses
O_NOATIME.  This confused us and caused us to die, saying that the
packfile is unreadable, when we should have just reported that the
object does not exist in that packfile to the caller.

* cb/open-noatime-clear-errno:
  git_open_noatime: return with errno=0 on success
2015-09-03 19:17:49 -07:00
Junio C Hamano
9b8d731995 Merge branch 'cb/open-noatime-clear-errno'
When trying to see that an object does not exist, a state errno
leaked from our "first try to open a packfile with O_NOATIME and
then if it fails retry without it" logic on a system that refuses
O_NOATIME.  This confused us and caused us to die, saying that the
packfile is unreadable, when we should have just reported that the
object does not exist in that packfile to the caller.

* cb/open-noatime-clear-errno:
  git_open_noatime: return with errno=0 on success
2015-08-25 14:57:10 -07:00
Junio C Hamano
8c9155e031 Merge branch 'jk/git-path'
git_path() and mkpath() are handy helper functions but it is easy
to misuse, as the callers need to be careful to keep the number of
active results below 4.  Their uses have been reduced.

* jk/git-path:
  memoize common git-path "constant" files
  get_repo_path: refactor path-allocation
  find_hook: keep our own static buffer
  refs.c: remove_empty_directories can take a strbuf
  refs.c: avoid git_path assignment in lock_ref_sha1_basic
  refs.c: avoid repeated git_path calls in rename_tmp_log
  refs.c: simplify strbufs in reflog setup and writing
  path.c: drop git_path_submodule
  refs.c: remove extra git_path calls from read_loose_refs
  remote.c: drop extraneous local variable from migrate_file
  prefer mkpathdup to mkpath in assignments
  prefer git_pathdup to git_path in some possibly-dangerous cases
  add_to_alternates_file: don't add duplicate entries
  t5700: modernize style
  cache.h: complete set of git_path_submodule helpers
  cache.h: clarify documentation for git_path, et al
2015-08-19 14:48:56 -07:00
Junio C Hamano
51a22ce147 Merge branch 'jc/finalize-temp-file'
Long overdue micro clean-up.

* jc/finalize-temp-file:
  sha1_file.c: rename move_temp_to_file() to finalize_object_file()
2015-08-19 14:48:55 -07:00
Junio C Hamano
0a489b0680 prepare_packed_git(): refactor garbage reporting in pack directory
The hook to report "garbage" files in $GIT_OBJECT_DIRECTORY/pack/
could be generic but is too specific to count-object's needs.

Move the part to produce human-readable messages to count-objects,
and refine the interface to callback with the "bits" with values
defined in the cache.h header file, so that other callers (e.g.
prune) can later use the same mechanism to enumerate different
kinds of garbage files and do something intelligent about them,
other than reporting in textual messages.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-17 09:14:59 -07:00
Clemens Buchacher
dff6f280df git_open_noatime: return with errno=0 on success
In read_sha1_file_extended we die if read_object fails with a fatal
error. We detect a fatal error if errno is non-zero and is not
ENOENT. If the object could not be read because it does not exist,
this is not considered a fatal error and we want to return NULL.

Somewhere down the line, read_object calls git_open_noatime to open
a pack index file, for example. We first try open with O_NOATIME.
If O_NOATIME fails with EPERM, we retry without O_NOATIME. When the
second open succeeds, errno is however still set to EPERM from the
first attempt. When we finally determine that the object does not
exist, read_object returns NULL and read_sha1_file_extended dies
with a fatal error:

    fatal: failed to read object <sha1>: Operation not permitted

Fix this by resetting errno to zero before we call open again.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Clemens Buchacher <clemens.buchacher@intel.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-12 13:56:19 -07:00
Johannes Sixt
094c7e6352 prune: close directory earlier during loose-object directory traversal
27e1e22d (prune: factor out loose-object directory traversal, 2014-10-16)
introduced a new function for_each_loose_file_in_objdir() with a helper
for_each_file_in_obj_subdir(). The latter calls callbacks for each file
found during a directory traversal and finally also a callback for the
directory itself.

git-prune uses the function to clean up the object directory. In
particular, in the directory callback it calls rmdir(). On Windows XP,
this rmdir call fails, because the directory is still open while the
callback is called. Close the directory before calling the callback.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-12 12:06:00 -07:00
Jeff King
77b9b1d13a add_to_alternates_file: don't add duplicate entries
The add_to_alternates_file function blindly uses
hold_lock_file_for_append to copy the existing contents, and
then adds the new line to it. This has two minor problems:

  1. We might add duplicate entries, which are ugly and
     inefficient.

  2. We do not check that the file ends with a newline, in
     which case we would bogusly append to the final line.
     This is quite unlikely in practice, though, as we call
     this function only from git-clone, so presumably we are
     the only writers of the file (and we always add a
     newline).

Instead of using hold_lock_file_for_append, let's copy the
file line by line, which ensures all records are properly
terminated. If we see an extra line, we can simply abort the
update (there is no point in even copying the rest, as we
know that it would be identical to the original).

As a bonus, we also get rid of some calls to the
static-buffer mkpath and git_path functions.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-10 15:15:42 -07:00
Junio C Hamano
cb5add5868 sha1_file.c: rename move_temp_to_file() to finalize_object_file()
Since 5a688fe4 ("core.sharedrepository = 0mode" should set, not
loosen, 2009-03-25), we kept reminding ourselves:

    NEEDSWORK: this should be renamed to finalize_temp_file() as
    "moving" is only a part of what it does, when no patch between
    master to pu changes the call sites of this function.

without doing anything about it.  Let's do so.

The purpose of this function was not to move but to finalize.  The
detail of the primarily implementation of finalizing was to link the
temporary file to its final name and then to unlink, which wasn't
even "moving".  The alternative implementation did "move" by calling
rename(2), which is a fun tangent.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-10 11:10:37 -07:00
Junio C Hamano
7c696007ca Merge branch 'jk/fix-refresh-utime' into maint
Fix a small bug in our use of umask() return value.

* jk/fix-refresh-utime:
  check_and_freshen_file: fix reversed success-check
2015-07-27 12:21:40 -07:00
Junio C Hamano
de62fe8c42 Merge branch 'jk/index-pack-reduce-recheck' into maint
Disable "have we lost a race with competing repack?" check while
receiving a huge object transfer that runs index-pack.

* jk/index-pack-reduce-recheck:
  index-pack: avoid excessive re-reading of pack directory
2015-07-27 12:21:38 -07:00
Junio C Hamano
1f9e0a5348 Merge branch 'jk/fix-refresh-utime'
Fix a small bug in our use of umask() return value.

* jk/fix-refresh-utime:
  check_and_freshen_file: fix reversed success-check
2015-07-10 14:26:15 -07:00
Junio C Hamano
c07173f215 Merge branch 'jk/maint-for-each-packed-object'
The for_each_packed_object() API function did not iterate over
objects in a packfile that hasn't been used yet.

* jk/maint-for-each-packed-object:
  for_each_packed_object: automatically open pack index
2015-07-09 14:31:43 -07:00
Jeff King
3096b2ecdb check_and_freshen_file: fix reversed success-check
When we want to write out a loose object file, we have
always first made sure we don't already have the object
somewhere. Since 33d4221 (write_sha1_file: freshen existing
objects, 2014-10-15), we also update the timestamp on the
file, so that a simultaneous prune knows somebody is
likely to reference it soon.

If our utime() call fails, we treat this the same as not
having the object in the first place; the safe thing to do
is write out another copy. However, the loose-object check
accidentally inverts the utime() check; it returns failure
_only_ when the utime() call actually succeeded. Thus it was
failing to protect us there, and in the normal case where
utime() succeeds, it caused us to pointlessly write out and
link the object.

This passed our freshening tests, because writing out the
new object is certainly _one_ way of updating its utime. So
the normal case was inefficient, but not wrong.

While we're here, let's also drop a comment in front of the
check_and_freshen functions, making a note of their return
type (since it is not our usual "0 for success, -1 for
error").

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-07-08 15:58:28 -07:00