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1467 commits

Author SHA1 Message Date
Jeff King 9a93c6686f avoid shifting signed integers 31 bits
We sometimes use 32-bit unsigned integers as bit-fields.
It's fine to access the MSB, because it's unsigned. However,
doing so as "1 << 31" is wrong, because the constant "1" is
a signed int, and we shift into the sign bit, causing
undefined behavior.

We can fix this by using "1U" as the constant.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-04 09:51:16 -08:00
Jeff King 9d98bbf578 pack-revindex: store entries directly in packed_git
A pack_revindex struct has two elements: the revindex
entries themselves, and a pointer to the packed_git. We need
both to do lookups, because only the latter knows things
like the number of objects in the pack.

Now that packed_git contains the pack_revindex struct it's
just as easy to pass around the packed_git itself, and we do
not need the extra back-pointer.

We can instead just store the entries directly in the pack.
All functions which took a pack_revindex now just take a
packed_git. We still lazy-load in find_pack_revindex, so
most callers are unaffected.

The exception is the bitmap code, which computes the
revindex and caches the pointer when we load the bitmaps. We
can continue to load, drop the extra cache pointer, and just
access bitmap_git.pack.revindex directly.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-12-21 14:36:28 -08:00
Jeff King f4015337da pack-revindex: drop hash table
The main entry point to the pack-revindex code is
find_pack_revindex(). This calls revindex_for_pack(), which
lazily computes and caches the revindex for the pack.

We store the cache in a very simple hash table. It's created
by init_pack_revindex(), which inserts an entry for every
packfile we know about, and we never grow or shrink the
hash. If we ever need the revindex for a pack that isn't in
the hash, we die() with an internal error.

This can lead to a race, because we may load more packs
after having called init_pack_revindex(). For example,
imagine we have one process which needs to look at the
revindex for a variety of objects (e.g., cat-file's
"%(objectsize:disk)" format).  Simultaneously, git-gc is
running, which is doing a `git repack -ad`. We might hit a
sequence like:

  1. We need the revidx for some packed object. We call
     find_pack_revindex() and end up in init_pack_revindex()
     to create the hash table for all packs we know about.

  2. We look up another object and can't find it, because
     the repack has removed the pack it's in. We re-scan the
     pack directory and find a new pack containing the
     object. It gets added to our packed_git list.

  3. We call find_pack_revindex() for the new object, which
     hits revindex_for_pack() for our new pack. It can't
     find the packed_git in the revindex hash, and dies.

You could also replace the `repack` above with a push or
fetch to create a new pack, though these are less likely
(you would have to somehow learn about the new objects to
look them up).

Prior to 1a6d8b9 (do not discard revindex when re-preparing
packfiles, 2014-01-15), this was safe, as we threw away the
revindex whenever we re-scanned the pack directory (and thus
re-created the revindex hash on the fly). However, we don't
want to simply revert that commit, as it was solving a
different race.

So we have a few options:

  - We can fix the race in 1a6d8b9 differently, by having
    the bitmap code look in the revindex hash instead of
    caching the pointer. But this would introduce a lot of
    extra hash lookups for common bitmap operations.

  - We could teach the revindex to dynamically add new packs
    to the hash table. This would perform the same, but
    would mean adding extra code to the revindex hash (which
    currently cannot be resized at all).

  - We can get rid of the hash table entirely. There is
    exactly one revindex per pack, so we can just store it
    in the packed_git struct. Since it's initialized lazily,
    it does not add to the startup cost.

    This is the best of both worlds: less code and fewer
    hash table lookups.  The original code likely avoided
    this in the name of encapsulation. But the packed_git
    and reverse_index code are fairly intimate already, so
    it's not much of a loss.

This patch implements the final option. It's a minimal
conversion that retains the pack_revindex struct. No callers
need to change, and we can do further cleanup in a follow-on
patch.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-12-21 14:36:11 -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
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
Junio C Hamano 844a9ce472 Merge branch 'bc/object-id'
More transition from "unsigned char[40]" to "struct object_id".

This needed a few merge fixups, but is mostly disentangled from other
topics.

* bc/object-id:
  remote: convert functions to struct object_id
  Remove get_object_hash.
  Convert struct object to object_id
  Add several uses of get_object_hash.
  object: introduce get_object_hash macro.
  ref_newer: convert to use struct object_id
  push_refs_with_export: convert to struct object_id
  get_remote_heads: convert to struct object_id
  parse_fetch: convert to use struct object_id
  add_sought_entry_mem: convert to struct object_id
  Convert struct ref to use object_id.
  sha1_file: introduce has_object_file helper.
2015-12-10 12:36:13 -08:00
Junio C Hamano b1cda70fff Merge branch 'dt/refs-backend-pre-vtable'
Code preparation for pluggable ref backends.

* dt/refs-backend-pre-vtable:
  refs: break out ref conflict checks
  files_log_ref_write: new function
  initdb: make safe_create_dir public
  refs: split filesystem-based refs code into a new file
  refs/refs-internal.h: new header file
  refname_is_safe(): improve docstring
  pack_if_possible_fn(): use ref_type() instead of is_per_worktree_ref()
  copy_msg(): rename to copy_reflog_msg()
  verify_refname_available(): new function
  verify_refname_available(): rename function
2015-12-08 14:14:49 -08:00
Junio C Hamano b5d2d8eef0 Merge branch 'ad/sha1-update-chunked' into maint
Apple's common crypto implementation of SHA1_Update() does not take
more than 4GB at a time, and we now have a compile-time workaround
for it.

* ad/sha1-update-chunked:
  sha1: allow limiting the size of the data passed to SHA1_Update()
  sha1: provide another level of indirection for the SHA-1 functions
2015-12-08 14:05:03 -08:00
Junio C Hamano b50ceab48f Merge branch 'dk/gc-idx-wo-pack' into maint
Having a leftover .idx file without corresponding .pack file in
the repository hurts performance; "git gc" learned to prune them.

We may want to do the same for .bitmap (and notice but not prune
.keep) without corresponding .pack, but that can be a separate
topic.

* 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
2015-12-04 11:33:08 -08:00
Junio C Hamano 4672123fe5 Merge branch 'ad/sha1-update-chunked'
Apple's common crypto implementation of SHA1_Update() does not take
more than 4GB at a time, and we now have a compile-time workaround
for it.

* ad/sha1-update-chunked:
  sha1: allow limiting the size of the data passed to SHA1_Update()
  sha1: provide another level of indirection for the SHA-1 functions
2015-12-04 11:19:10 -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
David Turner eb33876c26 initdb: make safe_create_dir public
Soon we will want to create initdb functions for ref backends, and
code from initdb that calls this function needs to move into the files
backend. So this function needs to be public.

Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jeff King <peff@peff.net>
2015-11-20 04:52:01 -05:00
Atousa Pahlevan Duprat 001fd7a90b sha1: allow limiting the size of the data passed to SHA1_Update()
Using the previous commit's inredirection mechanism for SHA1,
support a chunked implementation of SHA1_Update() that limits the
amount of data in the chunk passed to SHA1_Update().

This is enabled by using the Makefile variable SHA1_MAX_BLOCK_SIZE
to specify chunk size.  When using Apple's CommonCrypto library this
is set to 1GiB (the implementation cannot handle more 4GiB).

Signed-off-by: Atousa Pahlevan Duprat <apahlevan@ieee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-11-05 10:35:11 -08:00
Atousa Pahlevan Duprat 3bc72fde3f sha1: provide another level of indirection for the SHA-1 functions
The git source uses git_SHA1_Update() and friends to call into the
code that computes the hashes.  Traditionally, we used to map these
directly to underlying implementation of the SHA-1 hash (e.g.
SHA1_Update() from OpenSSL or blk_SHA1_Update() from block-sha1/).

This arrangement however makes it hard to tweak behaviour of the
underlying implementation without fully replacing.  If we want to
introduce a tweaked_SHA1_Update() wrapper to implement the "Update"
in a slightly different way, for example, the implementation of the
wrapper still would want to call into the underlying implementation,
but tweaked_SHA1_Update() cannot call git_SHA1_Update() to get to
the underlying implementation (often but not always SHA1_Update()).

Add another level of indirection that maps platform_SHA1_Update()
and friends to their underlying implementations, and by default make
git_SHA1_Update() and friends map to platform_SHA1_* functions.

Doing it this way will later allow us to map git_SHA1_Update() to
tweaked_SHA1_Update(), and the latter can use platform_SHA1_Update()
in its implementation.

Signed-off-by: Atousa Pahlevan Duprat <apahlevan@ieee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-11-05 10:35:11 -08:00
Junio C Hamano 3a27eec48e Merge branch 'dt/name-hash-dir-entry-fix' into maint
The name-hash subsystem that is used to cope with case insensitive
filesystems keeps track of directories and their on-filesystem
cases for all the paths in the index by holding a pointer to a
randomly chosen cache entry that is inside the directory (for its
ce->ce_name component).  This pointer was not updated even when the
cache entry was removed from the index, leading to use after free.
This was fixed by recording the path for each directory instead of
borrowing cache entries and restructuring the API somewhat.

* dt/name-hash-dir-entry-fix:
  name-hash: don't reuse cache_entry in dir_entry
2015-11-03 15:32:40 -08:00
Junio C Hamano 1bf986bc9c Merge branch 'mk/submodule-gitdir-path' into maint
The submodule code has been taught to work better with separate
work trees created via "git worktree add".

* mk/submodule-gitdir-path:
  path: implement common_dir handling in git_pathdup_submodule()
  submodule refactor: use strbuf_git_path_submodule() in add_submodule_odb()
2015-11-03 15:32:35 -08:00
Junio C Hamano f836a32ba7 Merge branch 'js/clone-dissociate' into maint
"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`
2015-11-03 15:32:29 -08:00
Junio C Hamano f89baca1b9 Merge branch 'jk/repository-extension' into maint
Prepare for Git on-disk repository representation to undergo
backward incompatible changes by introducing a new repository
format version "1", with an extension mechanism.

* jk/repository-extension:
  introduce "preciousObjects" repository extension
  introduce "extensions" form of core.repositoryformatversion
2015-11-03 15:32:25 -08:00
Junio C Hamano 69fe31887b Merge branch 'dt/name-hash-dir-entry-fix'
The name-hash subsystem that is used to cope with case insensitive
filesystems keeps track of directories and their on-filesystem
cases for all the paths in the index by holding a pointer to a
randomly chosen cache entry that is inside the directory (for its
ce->ce_name component).  This pointer was not updated even when the
cache entry was removed from the index, leading to use after free.
This was fixed by recording the path for each directory instead of
borrowing cache entries and restructuring the API somewhat.

* dt/name-hash-dir-entry-fix:
  name-hash: don't reuse cache_entry in dir_entry
2015-10-29 13:59:19 -07:00
Junio C Hamano fa46579555 Merge branch 'jk/repository-extension'
Prepare for Git on-disk repository representation to undergo
backward incompatible changes by introducing a new repository
format version "1", with an extension mechanism.

* jk/repository-extension:
  introduce "preciousObjects" repository extension
  introduce "extensions" form of core.repositoryformatversion
2015-10-26 15:55:25 -07:00
David Turner 41284eb0f9 name-hash: don't reuse cache_entry in dir_entry
Stop reusing cache_entry in dir_entry; doing so causes a
use-after-free bug.

During merges, we free entries that we no longer need in the
destination index.  But those entries might have also been stored in
the dir_entry cache, and when a later call to add_to_index found them,
they would be used after being freed.

To prevent this, change dir_entry to store a copy of the name instead
of a pointer to a cache_entry.  This entails some refactoring of code
that expects the cache_entry.

Keith McGuigan <kmcguigan@twitter.com> diagnosed this bug and wrote
the initial patch, but this version does not use any of Keith's code.

Helped-by: Keith McGuigan <kmcguigan@twitter.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-21 12:47:38 -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
Junio C Hamano 1c630badac Merge branch 'mk/submodule-gitdir-path'
The submodule code has been taught to work better with separate
work trees created via "git worktree add".

* mk/submodule-gitdir-path:
  path: implement common_dir handling in git_pathdup_submodule()
  submodule refactor: use strbuf_git_path_submodule() in add_submodule_odb()
2015-10-15 15:43:32 -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
Junio C Hamano 7b09c459d3 Merge branch 'jk/date-local'
"git log --date=local" used to only show the normal (default)
format in the local timezone.  The command learned to take 'local'
as an instruction to use the local timezone with other formats,
e.g. "git show --date=rfc-local".

* jk/date-local:
  t6300: add tests for "-local" date formats
  t6300: make UTC and local dates different
  date: make "local" orthogonal to date format
  date: check for "local" before anything else
  t6300: add test for "raw" date format
  t6300: introduce test_date() helper
  fast-import: switch crash-report date to iso8601
  Documentation/rev-list: don't list date formats
  Documentation/git-for-each-ref: don't list date formats
  Documentation/config: don't list date formats
  Documentation/blame-options: don't list date formats
2015-10-05 12:30:13 -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 af49c6d091 add reentrant variants of sha1_to_hex and find_unique_abbrev
The sha1_to_hex and find_unique_abbrev functions always
write into reusable static buffers. There are a few problems
with this:

  - future calls overwrite our result. This is especially
    annoying with find_unique_abbrev, which does not have a
    ring of buffers, so you cannot even printf() a result
    that has two abbreviated sha1s.

  - if you want to put the result into another buffer, we
    often strcpy, which looks suspicious when auditing for
    overflows.

This patch introduces sha1_to_hex_r and find_unique_abbrev_r,
which write into a user-provided buffer. Of course this is
just punting on the overflow-auditing, as the buffer
obviously needs to be GIT_SHA1_HEXSZ + 1 bytes. But it is
much easier to audit, since that is a well-known size.

We retain the non-reentrant forms, which just become thin
wrappers around the reentrant ones. This patch also adds a
strbuf variant of find_unique_abbrev, which will be handy in
later patches.

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 bb3788cebb add git_path_buf helper function
If you have a function that uses git_path a lot, but would
prefer to avoid the static buffers, it's useful to keep a
single scratch buffer locally and reuse it for each call.
You used to be able to do this with git_snpath:

  char buf[PATH_MAX];

  foo(git_snpath(buf, sizeof(buf), "foo"));
  bar(git_snpath(buf, sizeof(buf), "bar"));

but since 1a83c24, git_snpath has been replaced with
strbuf_git_path. This is good, because it removes the
arbitrary PATH_MAX limit. But using strbuf_git_path is more
awkward for two reasons:

  1. It adds to the buffer, rather than replacing it. This
     is consistent with other strbuf functions, but makes
     reuse of a single buffer more tedious.

  2. It doesn't return the buffer, so you can't format
     as part of a function's arguments.

The new git_path_buf solves both of these, so you can use it
like:

  struct strbuf buf = STRBUF_INIT;

  foo(git_path_buf(&buf, "foo"));
  bar(git_path_buf(&buf, "bar"));

  strbuf_release(&buf);

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
Max Kirillov 11f9dd7191 path: implement common_dir handling in git_pathdup_submodule()
When submodule is a linked worktree, "git diff --submodule" and other
calls which directly access the submodule's object database do not correctly
calculate its path. Fix it by changing the git_pathdup_submodule() behavior,
to use either common or per-worktree directory.

Do it similarly as for parent repository, but ignore the GIT_COMMON_DIR
environment variable, because it would mean common directory for the parent
repository and does not make sense for submodule.

Also add test for functionality which uses this call.

Signed-off-by: Max Kirillov <max@max630.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-14 11:03:46 -07:00
Nguyễn Thái Ngọc Duy 895ff3b2c7 add and use a convenience macro ce_intent_to_add()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-06 20:01:13 -07:00
Jeff King add00ba2de date: make "local" orthogonal to date format
Most of our "--date" modes are about the format of the date:
which items we show and in what order. But "--date=local" is
a bit of an oddball. It means "show the date in the normal
format, but using the local timezone". The timezone we use
is orthogonal to the actual format, and there is no reason
we could not have "localized iso8601", etc.

This patch adds a "local" boolean field to "struct
date_mode", and drops the DATE_LOCAL element from the
date_mode_type enum (it's now just DATE_NORMAL plus
local=1). The new feature is accessible to users by adding
"-local" to any date mode (e.g., "iso-local"), and we retain
"local" as an alias for "default-local" for backwards
compatibility.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-03 15:45:26 -07:00
Junio C Hamano b21089db6a Merge branch 'db/push-sign-if-asked'
The client side codepaths in "git push" have been cleaned up
and the user can request to perform an optional "signed push",
i.e. sign only when the other end accepts signed push.

* db/push-sign-if-asked:
  push: add a config option push.gpgSign for default signed pushes
  push: support signing pushes iff the server supports it
  builtin/send-pack.c: use parse_options API
  config.c: rename git_config_maybe_bool_text and export it as git_parse_maybe_bool
  transport: remove git_transport_options.push_cert
  gitremote-helpers.txt: document pushcert option
  Documentation/git-send-pack.txt: document --signed
  Documentation/git-send-pack.txt: wrap long synopsis line
  Documentation/git-push.txt: document when --signed may fail
2015-08-31 15:39:08 -07:00
Junio C Hamano d75bb73bcf Merge branch 'jc/am-state-fix'
Recent reimplementation of "git am" changed the format of state
files kept in $GIT_DIR/rebase-apply/ without meaning to do so,
primarily because write_file() API was cumbersome to use and it was
easy to mistakenly make text files with incomplete lines.  Update
write_file() interface to make it harder to misuse.

* jc/am-state-fix:
  write_file(): drop caller-supplied LF from calls to create a one-liner file
  write_file_v(): do not leave incomplete line at the end
  write_file(): drop "fatal" parameter
  builtin/am: make sure state files are text
  builtin/am: introduce write_state_*() helper functions
2015-08-31 15:39:03 -07:00
Junio C Hamano 7b7c10bf5e Merge branch 'jk/fix-alias-pager-config-key-warnings'
Because the configuration system does not allow "alias.0foo" and
"pager.0foo" as the configuration key, the user cannot use '0foo'
as a custom command name anyway, but "git 0foo" tried to look these
keys up and emitted useless warnings before saying '0foo is not a
git command'.  These warning messages have been squelched.

* jk/fix-alias-pager-config-key-warnings:
  config: silence warnings for command names with invalid keys
2015-08-31 15:38:57 -07:00
Junio C Hamano 12d6ce1dba write_file(): drop "fatal" parameter
All callers except three passed 1 for the "fatal" parameter to ask
this function to die upon error, but to a casual reader of the code,
it was not all obvious what that 1 meant.  Instead, split the
function into two based on a common write_file_v() that takes the
flag, introduce write_file_gently() as a new way to attempt creating
a file without dying on error, and make three callers to call it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-24 13:09:02 -07:00
Jeff King 9e9de18f1a config: silence warnings for command names with invalid keys
When we are running the git command "foo", we may have to
look up the config keys "pager.foo" and "alias.foo". These
config schemes are mis-designed, as the command names can be
anything, but the config syntax has some restrictions. For
example:

  $ git foo_bar
  error: invalid key: pager.foo_bar
  error: invalid key: alias.foo_bar
  git: 'foo_bar' is not a git command. See 'git --help'.

You cannot name an alias with an underscore. And if you have
an external command with one, you cannot configure its
pager.

In the long run, we may develop a different config scheme
for these features. But in the near term (and because we'll
need to support the existing scheme indefinitely), we should
at least squelch the error messages shown above.

These errors come from git_config_parse_key. Ideally we
would pass a "quiet" flag to the config machinery, but there
are many layers between the pager code and the key parsing.
Passing a flag through all of those would be an invasive
change.

Instead, let's provide a config function to report on
whether a key is syntactically valid, and have the pager and
alias code skip lookup for bogus keys. We can build this
easily around the existing git_config_parse_key, with two
minor modifications:

  1. We now handle a NULL store_key, to validate but not
     write out the normalized key.

  2. We accept a "quiet" flag to avoid writing to stderr.
     This doesn't need to be a full-blown public "flags"
     field, because we can make the existing implementation
     a static helper function, keeping the mess contained
     inside config.c.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-24 08:52:23 -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
Dave Borowitz 9a549d4397 config.c: rename git_config_maybe_bool_text and export it as git_parse_maybe_bool
This helper function does not complain about the config variable
but just silently reports failure to the caller.  It is useful for
callers that need to parse any string that could be boolean or other
string (e.g. tristate yes/no/auto).

Signed-off-by: Dave Borowitz <dborowitz@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-19 12:43:22 -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
Jeff King f932729cc7 memoize common git-path "constant" files
One of the most common uses of git_path() is to pass a
constant, like git_path("MERGE_MSG"). This has two
drawbacks:

  1. The return value is a static buffer, and the lifetime
     is dependent on other calls to git_path, etc.

  2. There's no compile-time checking of the pathname. This
     is OK for a one-off (after all, we have to spell it
     correctly at least once), but many of these constant
     strings appear throughout the code.

This patch introduces a series of functions to "memoize"
these strings, which are essentially globals for the
lifetime of the program. We compute the value once, take
ownership of the buffer, and return the cached value for
subsequent calls.  cache.h provides a helper macro for
defining these functions as one-liners, and defines a few
common ones for global use.

Using a macro is a little bit gross, but it does nicely
document the purpose of the functions. If we need to touch
them all later (e.g., because we learned how to change the
git_dir variable at runtime, and need to invalidate all of
the stored values), it will be much easier to have the
complete list.

Note that the shared-global functions have separate, manual
declarations. We could do something clever with the macros
(e.g., expand it to a declaration in some places, and a
declaration _and_ a definition in path.c). But there aren't
that many, and it's probably better to stay away from
too-magical macros.

Likewise, if we abandon the C preprocessor in favor of
generating these with a script, we could get much fancier.
E.g., normalizing "FOO/BAR-BAZ" into "git_path_foo_bar_baz".
But the small amount of saved typing is probably not worth
the resulting confusion to readers who want to grep for the
function's definition.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-10 15:37:14 -07:00
Jeff King 07e3070d2a path.c: drop git_path_submodule
There are no callers of the slightly-dangerous static-buffer
git_path_submodule left. Let's drop it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-10 15:37:13 -07:00
Jeff King f5895fd399 cache.h: complete set of git_path_submodule helpers
The git_path function has "git_pathdup" and
"strbuf_git_path" variants, but git_submodule_path only
comes in the dangerous, static-buffer variant. That makes
refactoring callers to use the safer functions hard (since
they don't exist).

Since we're already using a strbuf behind the scenes, it's
easy to expose all three of these interfaces with thin
wrappers.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-10 15:15:41 -07:00
Jeff King 69ddd231fe cache.h: clarify documentation for git_path, et al
The comment above these functions actually describes
sha1_file_name, and comes from the very first revision of
git. Commit 723c31f (Add "git_path()" and "head_ref()"
helper functions., 2005-07-05) added git_path, pushing the
comment away from the function it describes; later commits
added more functions in this block.

Let's fix the comment to describe these related functions in
more detail. Let's also make sure to point out their safer
alternatives (and move those alternatives below, which makes
more sense when reading the file).

Note that we do not need to move the existing comment to
sha1_file_name.  Commit d40d535 (sha1_file.c: document a
bunch of functions defined in the file, 2014-02-21) already
added a much more descriptive comment to it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-10 15:15:41 -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 d939af12bd Merge branch 'jk/date-mode-format'
Teach "git log" and friends a new "--date=format:..." option to
format timestamps using system's strftime(3).

* jk/date-mode-format:
  strbuf: make strbuf_addftime more robust
  introduce "format" date-mode
  convert "enum date_mode" into a struct
  show-branch: use DATE_RELATIVE instead of magic number
2015-08-03 11:01:27 -07:00
Junio C Hamano be9cb560e3 Merge branch 'mh/init-delete-refs-api'
Clean up refs API and make "git clone" less intimate with the
implementation detail.

* mh/init-delete-refs-api:
  delete_ref(): use the usual convention for old_sha1
  cmd_update_ref(): make logic more straightforward
  update_ref(): don't read old reference value before delete
  check_branch_commit(): make first parameter const
  refs.h: add some parameter names to function declarations
  refs: move the remaining ref module declarations to refs.h
  initial_ref_transaction_commit(): check for ref D/F conflicts
  initial_ref_transaction_commit(): check for duplicate refs
  refs: remove some functions from the module's public interface
  initial_ref_transaction_commit(): function for initial ref creation
  repack_without_refs(): make function private
  prune_refs(): use delete_refs()
  prune_remote(): use delete_refs()
  delete_refs(): bail early if the packed-refs file cannot be rewritten
  delete_refs(): make error message more generic
  delete_refs(): new function for the refs API
  delete_ref(): handle special case more explicitly
  remove_branches(): remove temporary
  delete_ref(): move declaration to refs.h
2015-08-03 11:01:17 -07:00
Junio C Hamano 54d673f25d Merge branch 'ee/clean-remove-dirs'
Replace "is this subdirectory a separate repository that should not
be touched?" check "git clean" does by checking if it has .git/HEAD
using the submodule-related code with a more optimized check.

* ee/clean-remove-dirs:
  read_gitfile_gently: fix use-after-free
  clean: improve performance when removing lots of directories
  p7300: add performance tests for clean
  t7300: add tests to document behavior of clean and nested git
  setup: sanity check file size in read_gitfile_gently
  setup: add gentle version of read_gitfile
2015-08-03 11:01:13 -07:00
Junio C Hamano 31a0ad5456 Merge branch 'mh/replace-refs'
Add an environment variable to tell Git to look into refs hierarchy
other than refs/replace/ for the object replacement data.

* mh/replace-refs:
  Allow to control where the replace refs are looked for
2015-08-03 11:01:10 -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
Jeff King aa1462cc3d introduce "format" date-mode
This feeds the format directly to strftime. Besides being a
little more flexible, the main advantage is that your system
strftime may know more about your locale's preferred format
(e.g., how to spell the days of the week).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-29 11:39:10 -07:00
Jeff King a5481a6c94 convert "enum date_mode" into a struct
In preparation for adding date modes that may carry extra
information beyond the mode itself, this patch converts the
date_mode enum into a struct.

Most of the conversion is fairly straightforward; we pass
the struct as a pointer and dereference the type field where
necessary. Locations that declare a date_mode can use a "{}"
constructor.  However, the tricky case is where we use the
enum labels as constants, like:

  show_date(t, tz, DATE_NORMAL);

Ideally we could say:

  show_date(t, tz, &{ DATE_NORMAL });

but of course C does not allow that. Likewise, we cannot
cast the constant to a struct, because we need to pass an
actual address. Our options are basically:

  1. Manually add a "struct date_mode d = { DATE_NORMAL }"
     definition to each caller, and pass "&d". This makes
     the callers uglier, because they sometimes do not even
     have their own scope (e.g., they are inside a switch
     statement).

  2. Provide a pre-made global "date_normal" struct that can
     be passed by address. We'd also need "date_rfc2822",
     "date_iso8601", and so forth. But at least the ugliness
     is defined in one place.

  3. Provide a wrapper that generates the correct struct on
     the fly. The big downside is that we end up pointing to
     a single global, which makes our wrapper non-reentrant.
     But show_date is already not reentrant, so it does not
     matter.

This patch implements 3, along with a minor macro to keep
the size of the callers sane.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-29 11:39:07 -07:00
Jeff King 067fbd4105 introduce "preciousObjects" repository extension
If this extension is used in a repository, then no
operations should run which may drop objects from the object
storage. This can be useful if you are sharing that storage
with other repositories whose refs you cannot see.

For instance, if you do:

  $ git clone -s parent child
  $ git -C parent config extensions.preciousObjects true
  $ git -C parent config core.repositoryformatversion 1

you now have additional safety when running git in the
parent repository. Prunes and repacks will bail with an
error, and `git gc` will skip those operations (it will
continue to pack refs and do other non-object operations).
Older versions of git, when run in the repository, will
fail on every operation.

Note that we do not set the preciousObjects extension by
default when doing a "clone -s", as doing so breaks
backwards compatibility. It is a decision the user should
make explicitly.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-24 17:09:35 -07:00
Jeff King 00a09d57eb introduce "extensions" form of core.repositoryformatversion
Normally we try to avoid bumps of the whole-repository
core.repositoryformatversion field. However, it is
unavoidable if we want to safely change certain aspects of
git in a backwards-incompatible way (e.g., modifying the set
of ref tips that we must traverse to generate a list of
unreachable, safe-to-prune objects).

If we were to bump the repository version for every such
change, then any implementation understanding version `X`
would also have to understand `X-1`, `X-2`, and so forth,
even though the incompatibilities may be in orthogonal parts
of the system, and there is otherwise no reason we cannot
implement one without the other (or more importantly, that
the user cannot choose to use one feature without the other,
weighing the tradeoff in compatibility only for that
particular feature).

This patch documents the existing repositoryformatversion
strategy and introduces a new format, "1", which lets a
repository specify that it must run with an arbitrary set of
extensions. This can be used, for example:

 - to inform git that the objects should not be pruned based
   only on the reachability of the ref tips (e.g, because it
   has "clone --shared" children)

 - that the refs are stored in a format besides the usual
   "refs" and "packed-refs" directories

Because we bump to format "1", and because format "1"
requires that a running git knows about any extensions
mentioned, we know that older versions of the code will not
do something dangerous when confronted with these new
formats.

For example, if the user chooses to use database storage for
refs, they may set the "extensions.refbackend" config to
"db". Older versions of git will not understand format "1"
and bail. Versions of git which understand "1" but do not
know about "refbackend", or which know about "refbackend"
but not about the "db" backend, will refuse to run. This is
annoying, of course, but much better than the alternative of
claiming that there are no refs in the repository, or
writing to a location that other implementations will not
read.

Note that we are only defining the rules for format 1 here.
We do not ever write format 1 ourselves; it is a tool that
is meant to be used by users and future extensions to
provide safety with older implementations.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-24 17:09:08 -07:00
Junio C Hamano 712b351bd3 Merge branch 'jk/index-pack-reduce-recheck'
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
2015-06-24 12:21:54 -07:00
Junio C Hamano 510ab3f3c1 Merge branch 'js/sleep-without-select'
Portability fix.

* js/sleep-without-select:
  lockfile: wait using sleep_millisec() instead of select()
  lockfile: convert retry timeout computations to millisecond
  help.c: wrap wait-only poll() invocation in sleep_millisec()
  lockfile: replace random() by rand()
2015-06-24 12:21:47 -07:00
Michael Haggerty fb58c8d507 refs: move the remaining ref module declarations to refs.h
Some functions from the refs module were still declared in cache.h.
Move them to refs.h.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22 13:17:12 -07:00
Michael Haggerty fc1c21689d delete_ref(): move declaration to refs.h
Also

* Add a docstring

* Rename the second parameter to "old_sha1", to be consistent with the
  convention used elsewhere in the refs module

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22 13:17:08 -07:00
Erik Elfström 921bdd96af setup: sanity check file size in read_gitfile_gently
read_gitfile_gently will allocate a buffer to fit the entire file that
should be read. Add a sanity check of the file size before opening to
avoid allocating a potentially huge amount of memory if we come across
a large file that someone happened to name ".git". The limit is set to
a sufficiently unreasonable size that should never be exceeded by a
genuine .git file.

Signed-off-by: Erik Elfström <erik.elfstrom@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-15 13:14:01 -07:00
Mike Hommey 58d121b22b Allow to control where the replace refs are looked for
It can be useful to have grafts or replace refs for specific use-cases while
keeping the default "view" of the repository pristine (or with a different
set of grafts/replace refs).

It is possible to use a different graft file with GIT_GRAFT_FILE, but while
replace refs are more powerful, they don't have an equivalent override.

Add a GIT_REPLACE_REF_BASE environment variable to control where git is
going to look for replace refs.

Signed-off-by: Mike Hommey <mh@glandium.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-12 15:28:17 -07:00
Erik Elfström a93bedada8 setup: add gentle version of read_gitfile
read_gitfile will die on most error cases. This makes it unsuitable
for speculative calls. Extract the core logic and provide a gentle
version that returns NULL on failure.

The first usecase of the new gentle version will be to probe for
submodules during git clean.

Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Erik Elfström <erik.elfstrom@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-09 12:29:22 -07:00
Jeff King 0eeb077be7 index-pack: avoid excessive re-reading of pack directory
Since 45e8a74 (has_sha1_file: re-check pack directory before
giving up, 2013-08-30), we spend extra effort for
has_sha1_file to give the right answer when somebody else is
repacking. Usually this effort does not matter, because
after finding that the object does not exist, the next step
is usually to die().

However, some code paths make a large number of
has_sha1_file checks which are _not_ expected to return 1.
The collision test in index-pack.c is such a case. On a
local system, this can cause a performance slowdown of
around 5%. But on a system with high-latency system calls
(like NFS), it can be much worse.

This patch introduces a "quick" flag to has_sha1_file which
callers can use when they would prefer high performance at
the cost of false negatives during repacks. There may be
other code paths that can use this, but the index-pack one
is the most obviously critical, so we'll start with
switching that one.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-09 12:26:35 -07:00
Johannes Sixt 2024d31765 help.c: wrap wait-only poll() invocation in sleep_millisec()
We want to use the new function elsewhere in a moment.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-05 15:00:32 -07:00
Junio C Hamano d9c82fa7a7 Merge branch 'pt/xdg-config-path' into maint
Code clean-up for xdg configuration path support.

* pt/xdg-config-path:
  path.c: remove home_config_paths()
  git-config: replace use of home_config_paths()
  git-commit: replace use of home_config_paths()
  credential-store.c: replace home_config_paths() with xdg_config_home()
  dir.c: replace home_config_paths() with xdg_config_home()
  attr.c: replace home_config_paths() with xdg_config_home()
  path.c: implement xdg_config_home()
  t0302: "unreadable" test needs POSIXPERM
  t0302: test credential-store support for XDG_CONFIG_HOME
  git-credential-store: support XDG_CONFIG_HOME
  git-credential-store: support multiple credential files
2015-06-05 12:00:04 -07:00
Junio C Hamano 67f0b6f3b2 Merge branch 'dt/cat-file-follow-symlinks'
"git cat-file --batch(-check)" learned the "--follow-symlinks"
option that follows an in-tree symbolic link when asked about an
object via extended SHA-1 syntax, e.g. HEAD:RelNotes that points at
Documentation/RelNotes/2.5.0.txt.  With the new option, the command
behaves as if HEAD:Documentation/RelNotes/2.5.0.txt was given as
input instead.

* dt/cat-file-follow-symlinks:
  cat-file: add --follow-symlinks to --batch
  sha1_name: get_sha1_with_context learns to follow symlinks
  tree-walk: learn get_tree_entry_follow_symlinks
2015-06-01 12:45:16 -07:00
Junio C Hamano 1e6c8babf8 Merge branch 'jc/hash-object' into maint
"hash-object --literally" introduced in v2.2 was not prepared to
take a really long object type name.

* jc/hash-object:
  write_sha1_file(): do not use a separate sha1[] array
  t1007: add hash-object --literally tests
  hash-object --literally: fix buffer overrun with extra-long object type
  git-hash-object.txt: document --literally option
2015-05-26 13:49:25 -07:00
Junio C Hamano 38ccaf93bb Merge branch 'nd/untracked-cache'
Teach the index to optionally remember already seen untracked files
to speed up "git status" in a working tree with tons of cruft.

* nd/untracked-cache: (24 commits)
  git-status.txt: advertisement for untracked cache
  untracked cache: guard and disable on system changes
  mingw32: add uname()
  t7063: tests for untracked cache
  update-index: test the system before enabling untracked cache
  update-index: manually enable or disable untracked cache
  status: enable untracked cache
  untracked-cache: temporarily disable with $GIT_DISABLE_UNTRACKED_CACHE
  untracked cache: mark index dirty if untracked cache is updated
  untracked cache: print stats with $GIT_TRACE_UNTRACKED_STATS
  untracked cache: avoid racy timestamps
  read-cache.c: split racy stat test to a separate function
  untracked cache: invalidate at index addition or removal
  untracked cache: load from UNTR index extension
  untracked cache: save to an index extension
  ewah: add convenient wrapper ewah_serialize_strbuf()
  untracked cache: don't open non-existent .gitignore
  untracked cache: mark what dirs should be recursed/saved
  untracked cache: record/validate dir mtime and reuse cached output
  untracked cache: make a wrapper around {open,read,close}dir()
  ...
2015-05-26 13:24:46 -07:00
Junio C Hamano ddaf4e2e9a Merge branch 'jc/ignore-epipe-in-filter'
Filter scripts were run with SIGPIPE disabled on the Git side,
expecting that they may not read what Git feeds them to filter.
We however treated a filter that does not read its input fully
before exiting as an error.

This changes semantics, but arguably in a good way.  If a filter
can produce its output without consuming its input using whatever
magic, we now let it do so, instead of diagnosing it as a
programming error.

* jc/ignore-epipe-in-filter:
  filter_buffer_or_fd(): ignore EPIPE
  copy.c: make copy_fd() report its status silently
2015-05-22 12:41:57 -07:00
David Turner c4ec96774b sha1_name: get_sha1_with_context learns to follow symlinks
Wire up get_sha1_with_context to call get_tree_entry_follow_symlinks
when GET_SHA1_FOLLOW_SYMLINKS is passed in flags. G_S_FOLLOW_SYMLINKS
is incompatible with G_S_ONLY_TO_DIE because the diagnosis
that ONLY_TO_DIE triggers does not at present consider symlinks, and
it would be a significant amount of additional code to allow it to
do so.

Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-20 13:46:13 -07:00
Junio C Hamano 00b7cbfcb3 copy.c: make copy_fd() report its status silently
When copy_fd() function encounters errors, it emits error messages
itself, which makes it impossible for callers to take responsibility
for reporting errors, especially when they want to ignore certain
errors.

Move the error reporting to its callers in preparation.

 - copy_file() and copy_file_with_time() by indirection get their
   own calls to error().

 - hold_lock_file_for_append(), when told to die on error, used to
   exit(128) relying on the error message from copy_fd(), but now it
   does its own die() instead.  Note that the callers that do not
   pass LOCK_DIE_ON_ERROR need to be adjusted for this change, but
   fortunately there is none ;-)

 - filter_buffer_or_fd() has its own error() already, in addition to
   the message from copy_fd(), so this will change the output but
   arguably in a better way.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-19 14:48:54 -07:00
Junio C Hamano 3b7d373ae2 Merge branch 'kn/cat-file-literally'
Add the "--allow-unknown-type" option to "cat-file" to allow
inspecting loose objects of an experimental or a broken type.

* kn/cat-file-literally:
  t1006: add tests for git cat-file --allow-unknown-type
  cat-file: teach cat-file a '--allow-unknown-type' option
  cat-file: make the options mutually exclusive
  sha1_file: support reading from a loose object of unknown type
2015-05-19 13:17:58 -07:00
Junio C Hamano ebb464f0cb Merge branch 'jk/prune-mtime' into maint
Access to objects in repositories that borrow from another one on a
slow NFS server unnecessarily got more expensive due to recent code
becoming more cautious in a naive way not to lose objects to pruning.

* jk/prune-mtime:
  sha1_file: only freshen packs once per run
  sha1_file: freshen pack objects before loose
  reachable: only mark local objects as recent
2015-05-13 14:05:50 -07:00
Junio C Hamano 558e5a8c40 Merge branch 'pt/xdg-config-path'
Code clean-up for xdg configuration path support.

* pt/xdg-config-path:
  path.c: remove home_config_paths()
  git-config: replace use of home_config_paths()
  git-commit: replace use of home_config_paths()
  credential-store.c: replace home_config_paths() with xdg_config_home()
  dir.c: replace home_config_paths() with xdg_config_home()
  attr.c: replace home_config_paths() with xdg_config_home()
  path.c: implement xdg_config_home()
2015-05-11 14:24:01 -07:00
Junio C Hamano 051086b947 Merge branch 'jc/hash-object'
"hash-object --literally" introduced in v2.2 was not prepared to
take a really long object type name.

* jc/hash-object:
  write_sha1_file(): do not use a separate sha1[] array
  t1007: add hash-object --literally tests
  hash-object --literally: fix buffer overrun with extra-long object type
  git-hash-object.txt: document --literally option
2015-05-11 14:23:59 -07:00
Junio C Hamano 68a2e6a2c8 Merge branch 'nd/multiple-work-trees'
A replacement for contrib/workdir/git-new-workdir that does not
rely on symbolic links and make sharing of objects and refs safer
by making the borrowee and borrowers aware of each other.

* nd/multiple-work-trees: (41 commits)
  prune --worktrees: fix expire vs worktree existence condition
  t1501: fix test with split index
  t2026: fix broken &&-chain
  t2026 needs procondition SANITY
  git-checkout.txt: a note about multiple checkout support for submodules
  checkout: add --ignore-other-wortrees
  checkout: pass whole struct to parse_branchname_arg instead of individual flags
  git-common-dir: make "modules/" per-working-directory directory
  checkout: do not fail if target is an empty directory
  t2025: add a test to make sure grafts is working from a linked checkout
  checkout: don't require a work tree when checking out into a new one
  git_path(): keep "info/sparse-checkout" per work-tree
  count-objects: report unused files in $GIT_DIR/worktrees/...
  gc: support prune --worktrees
  gc: factor out gc.pruneexpire parsing code
  gc: style change -- no SP before closing parenthesis
  checkout: clean up half-prepared directories in --to mode
  checkout: reject if the branch is already checked out elsewhere
  prune: strategies for linked checkouts
  checkout: support checking out into a new working directory
  ...
2015-05-11 14:23:39 -07:00
Karthik Nayak 46f034483e sha1_file: support reading from a loose object of unknown type
Update sha1_loose_object_info() to optionally allow it to read
from a loose object file of unknown/bogus type; as the function
usually returns the type of the object it read in the form of enum
for known types, add an optional "typename" field to receive the
name of the type in textual form and a flag to indicate the reading
of a loose object file of unknown/bogus type.

Add parse_sha1_header_extended() which acts as a wrapper around
parse_sha1_header() allowing more information to be obtained.

Add unpack_sha1_header_to_strbuf() to unpack sha1 headers of
unknown/corrupt objects which have a unknown sha1 header size to
a strbuf structure. This was written by Junio C Hamano but tested
by me.

Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Hepled-by: Jeff King <peff@peff.net>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-06 13:35:48 -07:00
Paul Tan 846e5dfbab path.c: remove home_config_paths()
home_config_paths() combines distinct functionality already implemented
by expand_user_path() and xdg_config_home(), and it also hard-codes the
path ~/.gitconfig, which makes it unsuitable to use for other home
config file paths. Since its use will just add unnecessary complexity to
the code, remove it.

Signed-off-by: Paul Tan <pyokagan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-06 11:33:53 -07:00
Paul Tan ea19289bc8 path.c: implement xdg_config_home()
The XDG base dir spec[1] specifies that configuration files be stored in
a subdirectory in $XDG_CONFIG_HOME. To construct such a configuration
file path, home_config_paths() can be used. However, home_config_paths()
combines distinct functionality:

1. Retrieve the home git config file path ~/.gitconfig

2. Construct the XDG config path of the file specified by `file`.

This function was introduced in commit 21cf3227 ("read (but not write)
from $XDG_CONFIG_HOME/git/config file").  While the intention of the
function was to allow the home directory configuration file path and the
xdg directory configuration file path to be retrieved with one function
call, the hard-coding of the path ~/.gitconfig prevents it from being
used for other configuration files. Furthermore, retrieving a file path
relative to the user's home directory can be done with
expand_user_path(). Hence, it can be seen that home_config_paths()
introduces unnecessary complexity, especially if a user just wants to
retrieve the xdg config file path.

As such, implement a simpler function xdg_config_home() for constructing
the XDG base dir spec configuration file path. This function, together
with expand_user_path(), can replace all uses of home_config_paths().

[1] http://standards.freedesktop.org/basedir-spec/basedir-spec-0.7.html

Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Paul Tan <pyokagan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-06 11:21:04 -07:00
Junio C Hamano e3b199aef1 Merge branch 'jk/prune-mtime'
Access to objects in repositories that borrow from another one on a
slow NFS server unnecessarily got more expensive due to recent code
becoming more cautious in a naive way not to lose objects to pruning.

* jk/prune-mtime:
  sha1_file: only freshen packs once per run
  sha1_file: freshen pack objects before loose
  reachable: only mark local objects as recent
2015-05-05 21:00:37 -07:00
Junio C Hamano a916cb5fb4 Merge branch 'bc/object-id'
Identify parts of the code that knows that we use SHA-1 hash to
name our objects too much, and use (1) symbolic constants instead
of hardcoded 20 as byte count and/or (2) use struct object_id
instead of unsigned char [20] for object names.

* bc/object-id:
  apply: convert threeway_stage to object_id
  patch-id: convert to use struct object_id
  commit: convert parts to struct object_id
  diff: convert struct combine_diff_path to object_id
  bulk-checkin.c: convert to use struct object_id
  zip: use GIT_SHA1_HEXSZ for trailers
  archive.c: convert to use struct object_id
  bisect.c: convert leaf functions to use struct object_id
  define utility functions for object IDs
  define a structure for object IDs
2015-05-05 21:00:23 -07:00
Eric Sunshine 0c3db67cc8 hash-object --literally: fix buffer overrun with extra-long object type
"hash-object" learned in 5ba9a93 (hash-object: add --literally
option, 2014-09-11) to allow crafting a corrupt/broken object of
unknown type.

When the user-provided type is particularly long, however, it can
overflow the relatively small stack-based character array handed to
write_sha1_file_prepare() by hash_sha1_file() and write_sha1_file(),
leading to stack corruption (and crash).  Introduce a custom helper
to allow arbitrarily long typenames just for "hash-object --literally".

[jc: Eric's original used a strbuf in the more common codepaths, and
I rewrote it to avoid penalizing the non-literally code. Bugs are mine]

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-05 10:14:18 -07:00
Jeff King ee1c6c34ac sha1_file: only freshen packs once per run
Since 33d4221 (write_sha1_file: freshen existing objects,
2014-10-15), we update the mtime of existing objects that we
would have written out (had they not existed). For the
common case in which many objects are packed, we may update
the mtime on a single packfile repeatedly. This can result
in a noticeable performance problem if calling utime() is
expensive (e.g., because your storage is on NFS).

We can fix this by keeping a per-pack flag that lets us
freshen only once per program invocation.

An alternative would be to keep the packed_git.mtime flag up
to date as we freshen, and freshen only once every N
seconds. In practice, it's not worth the complexity. We are
racing against prune expiration times here, which inherently
must be set to accomodate reasonable program running times
(because they really care about the time between an object
being written and it becoming referenced, and the latter is
typically the last step a program takes).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-04-20 13:09:40 -07:00
Jeff King 1385bb7ba3 reachable: only mark local objects as recent
When pruning and repacking a repository that has an
alternate object store configured, we may traverse a large
number of objects in the alternate. This serves no purpose,
and may be expensive to do. A longer explanation is below.

Commits d3038d2 and abcb865 taught prune and pack-objects
(respectively) to treat "recent" objects as tips for
reachability, so that we keep whole chunks of history. They
built on the object traversal in 660c889 (sha1_file: add
for_each iterators for loose and packed objects,
2014-10-15), which covers both local and alternate objects.

In both cases, covering alternate objects is unnecessary, as
both commands can only drop objects from the local
repository. In the case of prune, we traverse only the local
object directory. And in the case of repacking, while we may
or may not include local objects in our pack, we will never
reach into the alternate with "repack -d". The "-l" option
is only a question of whether we are migrating objects from
the alternate into our repository, or leaving them
untouched.

It is possible that we may drop an object that is depended
upon by another object in the alternate. For example,
imagine two repositories, A and B, with A pointing to B as
an alternate. Now imagine a commit that is in B which
references a tree that is only in A. Traversing from recent
objects in B might prevent A from dropping that tree. But
this case isn't worth covering. Repo B should take
responsibility for its own objects. It would never have had
the commit in the first place if it did not also have the
tree, and assuming it is using the same "keep recent chunks
of history" scheme, then it would itself keep the tree, as
well.

So checking the alternate objects is not worth doing, and
come with a significant performance impact. In both cases,
we skip any recent objects that have already been marked
SEEN (i.e., that we know are already reachable for prune, or
included in the pack for a repack). So there is a slight
waste of time in opening the alternate packs at all, only to
notice that we have already considered each object. But much
worse, the alternate repository may have a large number of
objects that are not reachable from the local repository at
all, and we end up adding them to the traversal.

We can fix this by considering only local unseen objects.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-04-20 13:09:27 -07:00
Junio C Hamano 574ee8ae86 Merge branch 'jc/report-path-error-to-dir'
Code clean-up.

* jc/report-path-error-to-dir:
  report_path_error(): move to dir.c
2015-03-26 11:57:13 -07:00
Junio C Hamano 05e816e37f Merge branch 'jk/prune-with-corrupt-refs'
"git prune" used to largely ignore broken refs when deciding which
objects are still being used, which could spread an existing small
damage and make it a larger one.

* jk/prune-with-corrupt-refs:
  refs.c: drop curate_packed_refs
  repack: turn on "ref paranoia" when doing a destructive repack
  prune: turn on ref_paranoia flag
  refs: introduce a "ref paranoia" flag
  t5312: test object deletion code paths in a corrupted repository
2015-03-25 12:54:26 -07:00
Junio C Hamano 777c55a616 report_path_error(): move to dir.c
The expected call sequence is for the caller to use match_pathspec()
repeatedly on a set of pathspecs, accumulating the "hits" in a
separate array, and then call this function to diagnose a pathspec
that never matched anything, as that can indicate a typo from the
command line, e.g. "git commit Maekfile".

Many builtin commands use this function from builtin/ls-files.c,
which is not a very healthy arrangement.  ls-files might have been
the first command to feel the need for such a helper, but the need
is shared by everybody who uses the "match and then report" pattern.

Move it to dir.c where match_pathspec() is defined.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-24 14:12:10 -07:00
Jeff King 49672f26d9 refs: introduce a "ref paranoia" flag
Most operations that iterate over refs are happy to ignore
broken cruft. However, some operations should be performed
with knowledge of these broken refs, because it is better
for the operation to choke on a missing object than it is to
silently pretend that the ref did not exist (e.g., if we are
computing the set of reachable tips in order to prune
objects).

These processes could just call for_each_rawref, except that
ref iteration is often hidden behind other interfaces. For
instance, for a destructive "repack -ad", we would have to
inform "pack-objects" that we are destructive, and then it
would in turn have to tell the revision code that our
"--all" should include broken refs.

It's much simpler to just set a global for "dangerous"
operations that includes broken refs in all iterations.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-20 12:40:49 -07:00
brian m. carlson aa1c6fdf47 define utility functions for object IDs
There are several utility functions (hashcmp and friends) that are used
for comparing object IDs (SHA-1 values).  Using these functions, which
take pointers to unsigned char, with struct object_id requires tiresome
access to the sha1 member, which bloats code and violates the desired
encapsulation.  Provide wrappers around these functions for struct
object_id for neater, more maintainable code.  Use the new constants to
avoid the hard-coded 20s and 40s throughout the original functions.

These functions simply call the underlying pointer-to-unsigned-char
versions to ensure that any performance improvements will be passed
through to the new functions.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-13 22:43:11 -07:00
brian m. carlson 5f7817c85d define a structure for object IDs
Many places throughout the code use "unsigned char [20]" to store object IDs
(SHA-1 values).  This leads to lots of hardcoded numbers throughout the
codebase.  It also leads to confusion about the purposes of a buffer.

Introduce a structure for object IDs.  This allows us to obtain the benefits
of compile-time checking for misuse.  The structure is expected to remain
the same size and have the same alignment requirements on all known
platforms, compared to the array of unsigned char, although this is not
required for correctness.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-13 22:43:11 -07:00
Nguyễn Thái Ngọc Duy 1bbb3dba3f untracked cache: mark index dirty if untracked cache is updated
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-12 13:45:17 -07:00
Nguyễn Thái Ngọc Duy ed4efab1b1 untracked cache: avoid racy timestamps
When a directory is updated within the same second that its timestamp
is last saved, we cannot realize the directory has been updated by
checking timestamps. Assume the worst (something is update). See
29e4d36 (Racy GIT - 2005-12-20) for more information.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-12 13:45:17 -07:00
Nguyễn Thái Ngọc Duy 83c094ad0d untracked cache: save to an index extension
Helped-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-12 13:45:16 -07:00
Junio C Hamano cbc8d6d8f8 Merge branch 'jk/prune-mtime' into maint
In v2.2.0, we broke "git prune" that runs in a repository that
borrows from an alternate object store.

* jk/prune-mtime:
  sha1_file: fix iterating loose alternate objects
  for_each_loose_file_in_objdir: take an optional strbuf path
2015-03-05 13:13:08 -08:00
Junio C Hamano 3bef3c12d6 Merge branch 'jk/decimal-width-for-uintmax' into maint
We didn't format an integer that wouldn't fit in "int" but in
"uintmax_t" correctly.

* jk/decimal-width-for-uintmax:
  decimal_width: avoid integer overflow
2015-03-05 13:12:59 -08:00
Junio C Hamano fd9de868c3 Merge branch 'mh/refs-have-new'
Simplify the ref transaction API around how "the ref should be
pointing at this object" is specified.

* mh/refs-have-new:
  refs.h: remove duplication in function docstrings
  update_ref(): improve documentation
  ref_transaction_verify(): new function to check a reference's value
  ref_transaction_delete(): check that old_sha1 is not null_sha1
  ref_transaction_create(): check that new_sha1 is valid
  commit: avoid race when creating orphan commits
  commit: add tests of commit races
  ref_transaction_delete(): remove "have_old" parameter
  ref_transaction_update(): remove "have_old" parameter
  struct ref_update: move "have_old" into "flags"
  refs.c: change some "flags" to "unsigned int"
  refs: remove the gap in the REF_* constant values
  refs: move REF_DELETING to refs.c
2015-03-05 12:45:39 -08:00
Junio C Hamano 7cf6232e2c Merge branch 'jk/prune-mtime'
In v2.2.0, we broke "git prune" that runs in a repository that
borrows from an alternate object store.

* jk/prune-mtime:
  sha1_file: fix iterating loose alternate objects
  for_each_loose_file_in_objdir: take an optional strbuf path
2015-02-22 12:28:28 -08:00
Junio C Hamano ca00db08da Merge branch 'jk/decimal-width-for-uintmax'
We didn't format an integer that wouldn't fit in "int" but in
"uintmax_t" correctly.

* jk/decimal-width-for-uintmax:
  decimal_width: avoid integer overflow
2015-02-18 11:45:02 -08:00
Michael Haggerty fec14ec38c refs.c: change some "flags" to "unsigned int"
Change the following functions' "flags" arguments from "int" to
"unsigned int":

 * ref_transaction_update()
 * ref_transaction_create()
 * ref_transaction_delete()
 * update_ref()
 * delete_ref()
 * lock_ref_sha1_basic()

Also change the "flags" member in "struct ref_update" to unsigned.

Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-02-17 11:22:29 -08:00
Jeff King e6f875e052 for_each_loose_file_in_objdir: take an optional strbuf path
We feed a root "objdir" path to this iterator function,
which then copies the result into a strbuf, so that it can
repeatedly append the object sub-directories to it. Let's
make it easy for callers to just pass us a strbuf in the
first place.

We leave the original interface as a convenience for callers
who want to just pass a const string like the result of
get_object_directory().

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-02-09 14:14:53 -08:00
Jeff King d306f3d351 decimal_width: avoid integer overflow
The decimal_width function originally appeared in blame.c as
"lineno_width", and was designed for calculating the
print-width of small-ish integer values (line numbers in
text files). In ec7ff5b, it was made into a reusable
function, and in dc801e7, we started using it to align
diffstats.

Binary files in a diffstat show byte counts rather than line
numbers, meaning they can be quite large (e.g., consider
adding or removing a 2GB file). decimal_width is not up to
the challenge for two reasons:

  1. It takes the value as an "int", whereas large files may
     easily surpass this. The value may be truncated, in
     which case we will produce an incorrect value.

  2. It counts "up" by repeatedly multiplying another
     integer by 10 until it surpasses the value.  This can
     cause an infinite loop when the value is close to the
     largest representable integer.

     For example, consider using a 32-bit signed integer,
     and a value of 2,140,000,000 (just shy of 2^31-1).
     We will count up and eventually see that 1,000,000,000
     is smaller than our value. The next step would be to
     multiply by 10 and see that 10,000,000,000 is too
     large, ending the loop. But we can't represent that
     value, and we have signed overflow.

     This is technically undefined behavior, but a common
     behavior is to lose the high bits, in which case our
     iterator will certainly be less than the number. So
     we'll keep multiplying, overflow again, and so on.

This patch changes the argument to a uintmax_t (the same
type we use to store the diffstat information for binary
filese), and counts "down" by repeatedly dividing our value
by 10.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-02-05 12:38:35 -08:00
Junio C Hamano 2f17ecbd8d Merge branch 'dm/compat-s-ifmt-for-zos'
Long overdue departure from the assumption that S_IFMT is shared by
everybody made in 2005.

* dm/compat-s-ifmt-for-zos:
  compat: convert modes to use portable file type values
2014-12-22 12:27:16 -08:00
Junio C Hamano 77933f4449 Sync with v2.1.4
* maint-2.1:
  Git 2.1.4
  Git 2.0.5
  Git 1.9.5
  Git 1.8.5.6
  fsck: complain about NTFS ".git" aliases in trees
  read-cache: optionally disallow NTFS .git variants
  path: add is_ntfs_dotgit() helper
  fsck: complain about HFS+ ".git" aliases in trees
  read-cache: optionally disallow HFS+ .git variants
  utf8: add is_hfs_dotgit() helper
  fsck: notice .git case-insensitively
  t1450: refactor ".", "..", and ".git" fsck tests
  verify_dotfile(): reject .git case-insensitively
  read-tree: add tests for confusing paths like ".." and ".git"
  unpack-trees: propagate errors adding entries to the index
2014-12-17 11:46:57 -08:00
Junio C Hamano 58f1d950e3 Sync with v2.0.5
* maint-2.0:
  Git 2.0.5
  Git 1.9.5
  Git 1.8.5.6
  fsck: complain about NTFS ".git" aliases in trees
  read-cache: optionally disallow NTFS .git variants
  path: add is_ntfs_dotgit() helper
  fsck: complain about HFS+ ".git" aliases in trees
  read-cache: optionally disallow HFS+ .git variants
  utf8: add is_hfs_dotgit() helper
  fsck: notice .git case-insensitively
  t1450: refactor ".", "..", and ".git" fsck tests
  verify_dotfile(): reject .git case-insensitively
  read-tree: add tests for confusing paths like ".." and ".git"
  unpack-trees: propagate errors adding entries to the index
2014-12-17 11:42:28 -08:00
Junio C Hamano 5e519fb8b0 Sync with v1.9.5
* maint-1.9:
  Git 1.9.5
  Git 1.8.5.6
  fsck: complain about NTFS ".git" aliases in trees
  read-cache: optionally disallow NTFS .git variants
  path: add is_ntfs_dotgit() helper
  fsck: complain about HFS+ ".git" aliases in trees
  read-cache: optionally disallow HFS+ .git variants
  utf8: add is_hfs_dotgit() helper
  fsck: notice .git case-insensitively
  t1450: refactor ".", "..", and ".git" fsck tests
  verify_dotfile(): reject .git case-insensitively
  read-tree: add tests for confusing paths like ".." and ".git"
  unpack-trees: propagate errors adding entries to the index
2014-12-17 11:28:54 -08:00
Junio C Hamano 6898b79721 Sync with v1.8.5.6
* maint-1.8.5:
  Git 1.8.5.6
  fsck: complain about NTFS ".git" aliases in trees
  read-cache: optionally disallow NTFS .git variants
  path: add is_ntfs_dotgit() helper
  fsck: complain about HFS+ ".git" aliases in trees
  read-cache: optionally disallow HFS+ .git variants
  utf8: add is_hfs_dotgit() helper
  fsck: notice .git case-insensitively
  t1450: refactor ".", "..", and ".git" fsck tests
  verify_dotfile(): reject .git case-insensitively
  read-tree: add tests for confusing paths like ".." and ".git"
  unpack-trees: propagate errors adding entries to the index
2014-12-17 11:20:31 -08:00
Johannes Schindelin 2b4c6efc82 read-cache: optionally disallow NTFS .git variants
The point of disallowing ".git" in the index is that we
would never want to accidentally overwrite files in the
repository directory. But this means we need to respect the
filesystem's idea of when two paths are equal. The prior
commit added a helper to make such a comparison for NTFS
and FAT32; let's use it in verify_path().

We make this check optional for two reasons:

  1. It restricts the set of allowable filenames, which is
     unnecessary for people who are not on NTFS nor FAT32.
     In practice this probably doesn't matter, though, as
     the restricted names are rather obscure and almost
     certainly would never come up in practice.

  2. It has a minor performance penalty for every path we
     insert into the index.

This patch ties the check to the core.protectNTFS config
option. Though this is expected to be most useful on Windows,
we allow it to be set everywhere, as NTFS may be mounted on
other platforms. The variable does default to on for Windows,
though.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-17 11:04:45 -08:00
Johannes Schindelin 1d1d69bc52 path: add is_ntfs_dotgit() helper
We do not allow paths with a ".git" component to be added to
the index, as that would mean repository contents could
overwrite our repository files. However, asking "is this
path the same as .git" is not as simple as strcmp() on some
filesystems.

On NTFS (and FAT32), there exist so-called "short names" for
backwards-compatibility: 8.3 compliant names that refer to the same files
as their long names. As ".git" is not an 8.3 compliant name, a short name
is generated automatically, typically "git~1".

Depending on the Windows version, any combination of trailing spaces and
periods are ignored, too, so that both "git~1." and ".git." still refer
to the Git directory. The reason is that 8.3 stores file names shorter
than 8 characters with trailing spaces. So literally, it does not matter
for the short name whether it is padded with spaces or whether it is
shorter than 8 characters, it is considered to be the exact same.

The period is the separator between file name and file extension, and
again, an empty extension consists just of spaces in 8.3 format. So
technically, we would need only take care of the equivalent of this
regex:
        (\.git {0,4}|git~1 {0,3})\. {0,3}

However, there are indications that at least some Windows versions might
be more lenient and accept arbitrary combinations of trailing spaces and
periods and strip them out. So we're playing it real safe here. Besides,
there can be little doubt about the intention behind using file names
matching even the more lenient pattern specified above, therefore we
should be fine with disallowing such patterns.

Extra care is taken to catch names such as '.\\.git\\booh' because the
backslash is marked as a directory separator only on Windows, and we want
to use this new helper function also in fsck on other platforms.

A big thank you goes to Ed Thomson and an unnamed Microsoft engineer for
the detailed analysis performed to come up with the corresponding fixes
for libgit2.

This commit adds a function to detect whether a given file name can refer
to the Git directory by mistake.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-17 11:04:45 -08:00
Jeff King a42643aa8d read-cache: optionally disallow HFS+ .git variants
The point of disallowing ".git" in the index is that we
would never want to accidentally overwrite files in the
repository directory. But this means we need to respect the
filesystem's idea of when two paths are equal. The prior
commit added a helper to make such a comparison for HFS+;
let's use it in verify_path.

We make this check optional for two reasons:

  1. It restricts the set of allowable filenames, which is
     unnecessary for people who are not on HFS+. In practice
     this probably doesn't matter, though, as the restricted
     names are rather obscure and almost certainly would
     never come up in practice.

  2. It has a minor performance penalty for every path we
     insert into the index.

This patch ties the check to the core.protectHFS config
option. Though this is expected to be most useful on OS X,
we allow it to be set everywhere, as HFS+ may be mounted on
other platforms. The variable does default to on for OS X,
though.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-17 11:04:44 -08:00
David Michael d543d9c0f4 compat: convert modes to use portable file type values
This adds simple wrapper functions around calls to stat(), fstat(),
and lstat() that translate the operating system's native file type
bits to those used by most operating systems.  It also rewrites the
S_IF* macros to the common values, so all file type processing is
performed using the translated modes.  This makes projects portable
across operating systems that use different file type definitions.

Only the file type bits may be affected by these compatibility
functions; the file permission bits are assumed to be 07777 and are
passed through unchanged.

Signed-off-by: David Michael <fedora.dm0@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-04 11:58:36 -08:00
Nguyễn Thái Ngọc Duy 77a6d84045 count-objects: report unused files in $GIT_DIR/worktrees/...
In linked checkouts, borrowed parts like config is taken from
$GIT_COMMON_DIR. $GIT_DIR/config is never used. Report them as
garbage.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:18 -08:00
Nguyễn Thái Ngọc Duy 316e53e68c wrapper.c: wrapper to open a file, fprintf then close
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:16 -08:00
Nguyễn Thái Ngọc Duy 31e26ebcb5 setup.c: support multi-checkout repo setup
The repo setup procedure is updated to detect $GIT_DIR/commondir and
set $GIT_COMMON_DIR properly.

The core.worktree is ignored when $GIT_COMMON_DIR is set. This is
because the config file is shared in multi-checkout setup, but
checkout directories _are_ different. Making core.worktree effective
in all checkouts mean it's back to a single checkout.

Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:15 -08:00
Nguyễn Thái Ngọc Duy c7b3a3d2fe $GIT_COMMON_DIR: a new environment variable
This variable is intended to support multiple working directories
attached to a repository. Such a repository may have a main working
directory, created by either "git init" or "git clone" and one or more
linked working directories. These working directories and the main
repository share the same repository directory.

In linked working directories, $GIT_COMMON_DIR must be defined to point
to the real repository directory and $GIT_DIR points to an unused
subdirectory inside $GIT_COMMON_DIR. File locations inside the
repository are reorganized from the linked worktree view point:

 - worktree-specific such as HEAD, logs/HEAD, index, other top-level
   refs and unrecognized files are from $GIT_DIR.

 - the rest like objects, refs, info, hooks, packed-refs, shallow...
   are from $GIT_COMMON_DIR (except info/sparse-checkout, but that's
   a separate patch)

Scripts are supposed to retrieve paths in $GIT_DIR with "git rev-parse
--git-path", which will take care of "$GIT_DIR vs $GIT_COMMON_DIR"
business.

The redirection is done by git_path(), git_pathdup() and
strbuf_git_path(). The selected list of paths goes to $GIT_COMMON_DIR,
not the other way around in case a developer adds a new
worktree-specific file and it's accidentally promoted to be shared
across repositories (this includes unknown files added by third party
commands)

The list of known files that belong to $GIT_DIR are:

ADD_EDIT.patch BISECT_ANCESTORS_OK BISECT_EXPECTED_REV BISECT_LOG
BISECT_NAMES CHERRY_PICK_HEAD COMMIT_MSG FETCH_HEAD HEAD MERGE_HEAD
MERGE_MODE MERGE_RR NOTES_EDITMSG NOTES_MERGE_WORKTREE ORIG_HEAD
REVERT_HEAD SQUASH_MSG TAG_EDITMSG fast_import_crash_* logs/HEAD
next-index-* rebase-apply rebase-merge rsync-refs-* sequencer/*
shallow_*

Path mapping is NOT done for git_path_submodule(). Multi-checkouts are
not supported as submodules.

Helped-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:13 -08:00
Nguyễn Thái Ngọc Duy 557bd833bb git_path(): be aware of file relocation in $GIT_DIR
We allow the user to relocate certain paths out of $GIT_DIR via
environment variables, e.g. GIT_OBJECT_DIRECTORY, GIT_INDEX_FILE and
GIT_GRAFT_FILE. Callers are not supposed to use git_path() or
git_pathdup() to get those paths. Instead they must use
get_object_directory(), get_index_file() and get_graft_file()
respectively. This is inconvenient and could be missed in review (for
example, there's git_path("objects/info/alternates") somewhere in
sha1_file.c).

This patch makes git_path() and git_pathdup() understand those
environment variables. So if you set GIT_OBJECT_DIRECTORY to /foo/bar,
git_path("objects/abc") should return /foo/bar/abc. The same is done
for the two remaining env variables.

"git rev-parse --git-path" is the wrapper for script use.

This patch kinda reverts a0279e1 (setup_git_env: use git_pathdup
instead of xmalloc + sprintf - 2014-06-19) because using git_pathdup
here would result in infinite recursion:

  setup_git_env() -> git_pathdup("objects") -> .. -> adjust_git_path()
  -> get_object_directory() -> oops, git_object_directory is NOT set
  yet -> setup_git_env()

I wanted to make git_pathdup_literal() that skips adjust_git_path().
But that won't work because later on when $GIT_COMMON_DIR is
introduced, git_pathdup_literal("objects") needs adjust_git_path() to
replace $GIT_DIR with $GIT_COMMON_DIR.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:11 -08:00
Nguyễn Thái Ngọc Duy 1a83c240f2 git_snpath(): retire and replace with strbuf_git_path()
In the previous patch, git_snpath() is modified to allocate a new
strbuf buffer because vsnpath() needs that. But that makes it
awkward because git_snpath() receives a pre-allocated buffer from
outside and has to copy data back. Rename it to strbuf_git_path()
and make it receive strbuf directly.

Using git_path() in update_refs_for_switch() which used to call
git_snpath() is safe because that function and all of its callers do
not keep any pointer to the round-robin buffer pool allocated by
get_pathname().

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:11 -08:00
Nguyễn Thái Ngọc Duy dcf692625a path.c: make get_pathname() call sites return const char *
Before the previous commit, get_pathname returns an array of PATH_MAX
length. Even if git_path() and similar functions does not use the
whole array, git_path() caller can, in theory.

After the commit, get_pathname() may return a buffer that has just
enough room for the returned string and git_path() caller should never
write beyond that.

Make git_path(), mkpath() and git_path_submodule() return a const
buffer to make sure callers do not write in it at all.

This could have been part of the previous commit, but the "const"
conversion is too much distraction from the core changes in path.c.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:10 -08:00
Junio C Hamano d70e331c0e Merge branch 'jk/prune-mtime'
Tighten the logic to decide that an unreachable cruft is
sufficiently old by covering corner cases such as an ancient object
becoming reachable and then going unreachable again, in which case
its retention period should be prolonged.

* jk/prune-mtime: (28 commits)
  drop add_object_array_with_mode
  revision: remove definition of unused 'add_object' function
  pack-objects: double-check options before discarding objects
  repack: pack objects mentioned by the index
  pack-objects: use argv_array
  reachable: use revision machinery's --indexed-objects code
  rev-list: add --indexed-objects option
  rev-list: document --reflog option
  t5516: test pushing a tag of an otherwise unreferenced blob
  traverse_commit_list: support pending blobs/trees with paths
  make add_object_array_with_context interface more sane
  write_sha1_file: freshen existing objects
  pack-objects: match prune logic for discarding objects
  pack-objects: refactor unpack-unreachable expiration check
  prune: keep objects reachable from recent objects
  sha1_file: add for_each iterators for loose and packed objects
  count-objects: use for_each_loose_file_in_objdir
  count-objects: do not use xsize_t when counting object size
  prune-packed: use for_each_loose_file_in_objdir
  reachable: mark index blobs as SEEN
  ...
2014-10-29 10:07:56 -07:00
Jeff King 660c889e46 sha1_file: add for_each iterators for loose and packed objects
We typically iterate over the reachable objects in a
repository by starting at the tips and walking the graph.
There's no easy way to iterate over all of the objects,
including unreachable ones. Let's provide a way of doing so.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-16 10:10:41 -07:00
Jeff King 27e1e22d5e prune: factor out loose-object directory traversal
Prune has to walk $GIT_DIR/objects/?? in order to find the
set of loose objects to prune. Other parts of the code
(e.g., count-objects) want to do the same. Let's factor it
out into a reusable for_each-style function.

Note that this is not quite a straight code movement. The
original code had strange behavior when it found a file of
the form "[0-9a-f]{2}/.{38}" that did _not_ contain all hex
digits. It executed a "break" from the loop, meaning that we
stopped pruning in that directory (but still pruned other
directories!). This was probably a bug; we do not want to
process the file as an object, but we should keep going
otherwise (and that is how the new code handles it).

We are also a little more careful with loose object
directories which fail to open. The original code silently
ignored any failures, but the new code will complain about
any problems besides ENOENT.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-16 10:10:39 -07:00
Jeff King fe1b22686f foreach_alt_odb: propagate return value from callback
We check the return value of the callback and stop iterating
if it is non-zero. However, we do not make the non-zero
return value available to the caller, so they have no way of
knowing whether the operation succeeded or not (technically
they can keep their own error flag in the callback data, but
that is unlike our other for_each functions).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-16 10:10:35 -07:00
Ronnie Sahlberg d0f810f0bc refs.c: allow listing and deleting badly named refs
We currently do not handle badly named refs well:

  $ cp .git/refs/heads/master .git/refs/heads/master.....@\*@\\.
  $ git branch
    fatal: Reference has invalid format: 'refs/heads/master.....@*@\.'
  $ git branch -D master.....@\*@\\.
    error: branch 'master.....@*@\.' not found.

Users cannot recover from a badly named ref without manually finding
and deleting the loose ref file or appropriate line in packed-refs.
Making that easier will make it easier to tweak the ref naming rules
in the future, for example to forbid shell metacharacters like '`'
and '"', without putting people in a state that is hard to get out of.

So allow "branch --list" to show these refs and allow "branch -d/-D"
and "update-ref -d" to delete them.  Other commands (for example to
rename refs) will continue to not handle these refs but can be changed
in later patches.

Details:

In resolving functions, refuse to resolve refs that don't pass the
git-check-ref-format(1) check unless the new RESOLVE_REF_ALLOW_BAD_NAME
flag is passed.  Even with RESOLVE_REF_ALLOW_BAD_NAME, refuse to
resolve refs that escape the refs/ directory and do not match the
pattern [A-Z_]* (think "HEAD" and "MERGE_HEAD").

In locking functions, refuse to act on badly named refs unless they
are being deleted and either are in the refs/ directory or match [A-Z_]*.

Just like other invalid refs, flag resolved, badly named refs with the
REF_ISBROKEN flag, treat them as resolving to null_sha1, and skip them
in all iteration functions except for for_each_rawref.

Flag badly named refs (but not symrefs pointing to badly named refs)
with a REF_BAD_NAME flag to make it easier for future callers to
notice and handle them specially.  For example, in a later patch
for-each-ref will use this flag to detect refs whose names can confuse
callers parsing for-each-ref output.

In the transaction API, refuse to create or update badly named refs,
but allow deleting them (unless they try to escape refs/ and don't match
[A-Z_]*).

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:26 -07:00
Jonathan Nieder 62a2d52514 branch -d: avoid repeated symref resolution
If a repository gets in a broken state with too much symref nesting,
it cannot be repaired with "git branch -d":

 $ git symbolic-ref refs/heads/nonsense refs/heads/nonsense
 $ git branch -d nonsense
 error: branch 'nonsense' not found.

Worse, "git update-ref --no-deref -d" doesn't work for such repairs
either:

 $ git update-ref -d refs/heads/nonsense
 error: unable to resolve reference refs/heads/nonsense: Too many levels of symbolic links

Fix both by teaching resolve_ref_unsafe a new RESOLVE_REF_NO_RECURSE
flag and passing it when appropriate.

Callers can still read the value of a symref (for example to print a
message about it) with that flag set --- resolve_ref_unsafe will
resolve one level of symrefs and stop there.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:25 -07:00
Ronnie Sahlberg 7695d118e5 refs.c: change resolve_ref_unsafe reading argument to be a flags field
resolve_ref_unsafe takes a boolean argument for reading (a nonexistent ref
resolves successfully for writing but not for reading).  Change this to be
a flags field instead, and pass the new constant RESOLVE_REF_READING when
we want this behaviour.

While at it, swap two of the arguments in the function to put output
arguments at the end.  As a nice side effect, this ensures that we can
catch callers that were unaware of the new API so they can be audited.

Give the wrapper functions resolve_refdup and read_ref_full the same
treatment for consistency.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-15 10:47:24 -07:00
Junio C Hamano bd107e1052 Merge branch 'mh/lockfile'
The lockfile API and its users have been cleaned up.

* mh/lockfile: (38 commits)
  lockfile.h: extract new header file for the functions in lockfile.c
  hold_locked_index(): move from lockfile.c to read-cache.c
  hold_lock_file_for_append(): restore errno before returning
  get_locked_file_path(): new function
  lockfile.c: rename static functions
  lockfile: rename LOCK_NODEREF to LOCK_NO_DEREF
  commit_lock_file_to(): refactor a helper out of commit_lock_file()
  trim_last_path_component(): replace last_path_elm()
  resolve_symlink(): take a strbuf parameter
  resolve_symlink(): use a strbuf for internal scratch space
  lockfile: change lock_file::filename into a strbuf
  commit_lock_file(): use a strbuf to manage temporary space
  try_merge_strategy(): use a statically-allocated lock_file object
  try_merge_strategy(): remove redundant lock_file allocation
  struct lock_file: declare some fields volatile
  lockfile: avoid transitory invalid states
  git_config_set_multivar_in_file(): avoid call to rollback_lock_file()
  dump_marks(): remove a redundant call to rollback_lock_file()
  api-lockfile: document edge cases
  commit_lock_file(): rollback lock file on failure to rename
  ...
2014-10-14 10:49:45 -07:00
Junio C Hamano f0d8900175 Merge branch 'sp/stream-clean-filter'
When running a required clean filter, we do not have to mmap the
original before feeding the filter.  Instead, stream the file
contents directly to the filter and process its output.

* sp/stream-clean-filter:
  sha1_file: don't convert off_t to size_t too early to avoid potential die()
  convert: stream from fd to required clean filter to reduce used address space
  copy_fd(): do not close the input file descriptor
  mmap_limit: introduce GIT_MMAP_LIMIT to allow testing expected mmap size
  memory_limit: use git_env_ulong() to parse GIT_ALLOC_LIMIT
  config.c: add git_env_ulong() to parse environment variable
  convert: drop arguments other than 'path' from would_convert_to_git()
2014-10-08 13:05:32 -07:00
Michael Haggerty 697cc8efd9 lockfile.h: extract new header file for the functions in lockfile.c
Move the interface declaration for the functions in lockfile.c from
cache.h to a new file, lockfile.h. Add #includes where necessary (and
remove some redundant includes of cache.h by files that already
include builtin.h).

Move the documentation of the lock_file state diagram from lockfile.c
to the new header file.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:56:14 -07:00
Michael Haggerty ec38b4e482 get_locked_file_path(): new function
Add a function to return the path of the file that is locked by a
lock_file object. This reduces the knowledge that callers have to have
about the lock_file layout.

Suggested-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:53:54 -07:00
Michael Haggerty 47ba4662bf lockfile: rename LOCK_NODEREF to LOCK_NO_DEREF
This makes it harder to misread the name as LOCK_NODE_REF.

Suggested-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:53:28 -07:00
Michael Haggerty 751bacedaa commit_lock_file_to(): refactor a helper out of commit_lock_file()
commit_locked_index(), when writing to an alternate index file,
duplicates (poorly) the code in commit_lock_file(). And anyway, it
shouldn't have to know so much about the internal workings of lockfile
objects. So extract a new function commit_lock_file_to() that does the
work common to the two functions, and call it from both
commit_lock_file() and commit_locked_index().

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:52:06 -07:00
Michael Haggerty cf6950d3bf lockfile: change lock_file::filename into a strbuf
For now, we still make sure to allocate at least PATH_MAX characters
for the strbuf because resolve_symlink() doesn't know how to expand
the space for its return value.  (That will be fixed in a moment.)

Another alternative would be to just use a strbuf as scratch space in
lock_file() but then store a pointer to the naked string in struct
lock_file.  But lock_file objects are often reused.  By reusing the
same strbuf, we can avoid having to reallocate the string most times
when a lock_file object is reused.

Helped-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:50:01 -07:00
Michael Haggerty 2091c5062c struct lock_file: declare some fields volatile
The function remove_lock_file_on_signal() is used as a signal handler.
It is not realistic to make the signal handler conform strictly to the
C standard, which is very restrictive about what a signal handler is
allowed to do.  But let's increase the likelihood that it will work:

The lock_file_list global variable and several fields from struct
lock_file are used by the signal handler.  Declare those values
"volatile" to (1) force the main process to write the values to RAM
promptly, and (2) prevent updates to these fields from being reordered
in a way that leaves an opportunity for a jump to the signal handler
while the object is in an inconsistent state.

We don't mark the filename field volatile because that would prevent
the use of strcpy(), and it is anyway unlikely that a compiler
re-orders a strcpy() call across other expressions.  So in practice it
should be possible to get away without "volatile" in the "filename"
case.

Suggested-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:49:00 -07:00
Michael Haggerty 707103fdfd lockfile: avoid transitory invalid states
Because remove_lock_file() can be called any time by the signal
handler, it is important that any lock_file objects that are in the
lock_file_list are always in a valid state.  And since lock_file
objects are often reused (but are never removed from lock_file_list),
that means we have to be careful whenever mutating a lock_file object
to always keep it in a well-defined state.

This was formerly not the case, because part of the state was encoded
by setting lk->filename to the empty string vs. a valid filename.  It
is wrong to assume that this string can be updated atomically; for
example, even

    strcpy(lk->filename, value)

is unsafe.  But the old code was even more reckless; for example,

    strcpy(lk->filename, path);
    if (!(flags & LOCK_NODEREF))
            resolve_symlink(lk->filename, max_path_len);
    strcat(lk->filename, ".lock");

During the call to resolve_symlink(), lk->filename contained the name
of the file that was being locked, not the name of the lockfile.  If a
signal were raised during that interval, then the signal handler would
have deleted the valuable file!

We could probably continue to use the filename field to encode the
state by being careful to write characters 1..N-1 of the filename
first, and then overwrite the NUL at filename[0] with the first
character of the filename, but that would be awkward and error-prone.

So, instead of using the filename field to determine whether the
lock_file object is active, add a new field "lock_file::active" for
this purpose.  Be careful to set this field only when filename really
contains the name of a file that should be deleted on cleanup.

Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:48:59 -07:00
Michael Haggerty 7108ad232f cache.h: define constants LOCK_SUFFIX and LOCK_SUFFIX_LEN
There are a few places that use these values, so define constants for
them.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:45:11 -07:00
Michael Haggerty e197c21807 unable_to_lock_die(): rename function from unable_to_lock_index_die()
This function is used for other things besides the index, so rename it
accordingly.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Reviewed-by: Ronnie Sahlberg <sahlberg@google.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-01 13:38:38 -07:00
Junio C Hamano 102edda4df Merge branch 'ta/config-add-to-empty-or-true-fix' into maint
"git config --add section.var val" used to lose existing
section.var whose value was an empty string.

* ta/config-add-to-empty-or-true-fix:
  config: avoid a funny sentinel value "a^"
  make config --add behave correctly for empty and NULL values
2014-09-29 22:10:25 -07:00
Junio C Hamano 1c2ea2cdc0 Merge branch 'rs/realloc-array'
Code cleanup.

* rs/realloc-array:
  use REALLOC_ARRAY for changing the allocation size of arrays
  add macro REALLOC_ARRAY
2014-09-26 14:39:45 -07:00
Junio C Hamano 69a5bbbbfa Merge branch 'jk/write-packed-refs-via-stdio'
Optimize the code path to write out the packed-refs file, which
especially matters in a repository with a large number of refs.

* jk/write-packed-refs-via-stdio:
  refs: write packed_refs file using stdio
2014-09-26 14:39:42 -07:00
Junio C Hamano 4daf5c8643 Merge branch 'ta/config-add-to-empty-or-true-fix'
"git config --add section.var val" used to lose existing
section.var whose value was an empty string.

* ta/config-add-to-empty-or-true-fix:
  config: avoid a funny sentinel value "a^"
  make config --add behave correctly for empty and NULL values
2014-09-19 11:38:40 -07:00
Junio C Hamano 9ff700ebac Merge branch 'jk/commit-author-parsing'
Code clean-up.

* jk/commit-author-parsing:
  determine_author_info(): copy getenv output
  determine_author_info(): reuse parsing functions
  date: use strbufs in date-formatting functions
  record_author_date(): use find_commit_header()
  record_author_date(): fix memory leak on malformed commit
  commit: provide a function to find a header in a buffer
2014-09-19 11:38:33 -07:00
Junio C Hamano ceeacc501b Merge branch 'bb/date-iso-strict'
"log --date=iso" uses a slight variant of ISO 8601 format that is
made more human readable.  A new "--date=iso-strict" option gives
datetime output that is more strictly conformant.

* bb/date-iso-strict:
  pretty: provide a strict ISO 8601 date format
2014-09-19 11:38:32 -07:00
René Scharfe 2756ca4347 use REALLOC_ARRAY for changing the allocation size of arrays
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-18 09:13:42 -07:00
Jeff King c1063be2a3 config: avoid a funny sentinel value "a^"
Introduce CONFIG_REGEX_NONE as a more explicit sentinel value to say
"we do not want to replace any existing entry" and use it in the
implementation of "git config --add".

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-11 16:33:54 -07:00
Junio C Hamano 7f346e9d73 Merge branch 'ta/config-set-1'
Use the new caching config-set API in git_config() calls.

* ta/config-set-1:
  add tests for `git_config_get_string_const()`
  add a test for semantic errors in config files
  rewrite git_config() to use the config-set API
  config: add `git_die_config()` to the config-set API
  change `git_config()` return value to void
  add line number and file name info to `config_set`
  config.c: fix accuracy of line number in errors
  config.c: mark error and warnings strings for translation
2014-09-11 10:33:25 -07:00
Jeff King 9540ce5030 refs: write packed_refs file using stdio
We write each line of a new packed-refs file individually
using a write() syscall (and sometimes 2, if the ref is
peeled). Since each line is only about 50-100 bytes long,
this creates a lot of system call overhead.

We can instead open a stdio handle around our descriptor and
use fprintf to write to it. The extra buffering is not a
problem for us, because nobody will read our new packed-refs
file until we call commit_lock_file (by which point we have
flushed everything).

On a pathological repository with 8.5 million refs, this
dropped the time to run `git pack-refs` from 20s to 6s.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-10 10:58:32 -07:00
Junio C Hamano 56f214e071 Merge branch 'ta/config-set'
Add in-core caching layer to let us avoid reading the same
configuration files number of times.

* ta/config-set:
  test-config: add tests for the config_set API
  add `config_set` API for caching config-like files
2014-09-02 13:24:18 -07:00
Junio C Hamano 1d8a6f6929 Merge branch 'mm/config-edit-global'
Start "git config --edit --global" from a skeletal per-user
configuration file contents, instead of a total blank, when the
user does not already have any.  This immediately reduces the need
for a later "Have you forgotten setting core.user?" and we can add
more to the template as we gain more experience.

* mm/config-edit-global:
  commit: advertise config --global --edit on guessed identity
  home_config_paths(): let the caller ignore xdg path
  config --global --edit: create a template file if needed
2014-09-02 13:23:20 -07:00
Junio C Hamano c518279c0e Merge branch 'jc/reopen-lock-file'
There are cases where you lock and open to write a file, close it to
show the updated contents to external processes, and then have to
update the file again while still holding the lock, but the lockfile
API lacked support for such an access pattern.

* jc/reopen-lock-file:
  lockfile: allow reopening a closed but still locked file
2014-09-02 13:20:13 -07:00
Beat Bolli 466fb6742d pretty: provide a strict ISO 8601 date format
Git's "ISO" date format does not really conform to the ISO 8601
standard due to small differences, and it cannot be parsed by ISO
8601-only parsers, e.g. those of XML toolchains.

The output from "--date=iso" deviates from ISO 8601 in these ways:

  - a space instead of the `T` date/time delimiter
  - a space between time and time zone
  - no colon between hours and minutes of the time zone

Add a strict ISO 8601 date format for displaying committer and
author dates.  Use the '%aI' and '%cI' format specifiers and add
'--date=iso-strict' or '--date=iso8601-strict' date format names.

See http://thread.gmane.org/gmane.comp.version-control.git/255879 and
http://thread.gmane.org/gmane.comp.version-control.git/52414/focus=52585
for discussion.

Signed-off-by: Beat Bolli <bbolli@ewanet.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-29 12:37:02 -07:00