Commit Graph

2206 Commits

Author SHA1 Message Date
Junio C Hamano
58d1772c85 Merge branch 'js/enhanced-version-info'
"git version --build-options" learned to report the host CPU and
the exact commit object name the binary was built from.

* js/enhanced-version-info:
  version --build-options: report commit, too, if possible
  version --build-options: also report host CPU
2017-12-28 14:08:47 -08:00
Junio C Hamano
eacf669cec Merge branch 'jt/decorate-api'
A few structures and variables that are implementation details of
the decorate API have been renamed and then the API got documented
better.

* jt/decorate-api:
  decorate: clean up and document API
2017-12-27 11:16:26 -08:00
Junio C Hamano
61061abba7 Merge branch 'jh/object-filtering'
In preparation for implementing narrow/partial clone, the object
walking machinery has been taught a way to tell it to "filter" some
objects from enumeration.

* jh/object-filtering:
  rev-list: support --no-filter argument
  list-objects-filter-options: support --no-filter
  list-objects-filter-options: fix 'keword' typo in comment
  pack-objects: add list-objects filtering
  rev-list: add list-objects filtering support
  list-objects: filter objects in traverse_commit_list
  oidset: add iterator methods to oidset
  oidmap: add oidmap iterator methods
  dir: allow exclusions from blob in addition to file
2017-12-27 11:16:21 -08:00
Junio C Hamano
66d3f19324 Merge branch 'tg/worktree-create-tracking'
The way "git worktree add" determines what branch to create from
where and checkout in the new worktree has been updated a bit.

* tg/worktree-create-tracking:
  add worktree.guessRemote config option
  worktree: add --guess-remote flag to add subcommand
  worktree: make add <path> <branch> dwim
  worktree: add --[no-]track option to the add subcommand
  worktree: add can be created from any commit-ish
  checkout: factor out functions to new lib file
2017-12-19 11:33:57 -08:00
Johannes Schindelin
ed32b788c0 version --build-options: report commit, too, if possible
In particular when local tags are used (or tags that are pushed to some
fork) to build Git, it is very hard to figure out from which particular
revision a particular Git executable was built. It gets worse when those
tags are deleted, or even updated.

Let's just report an exact, unabbreviated commit name in our build
options.

We need to be careful, though, to report when the current commit cannot
be determined, e.g. when building from a tarball without any associated
Git repository. This could be the case also when extracting Git's source
code into an unrelated Git worktree.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-14 22:53:04 -08:00
Eric Sunshine
b22894049f version --build-options: also report host CPU
It can be helpful for bug reports to include information about the
environment in which the bug occurs. "git version --build-options" can
help to supplement this information. In addition to the size of 'long'
already reported by --build-options, also report the host's CPU type.
Example output:

   $ git version --build-options
   git version 2.9.3.windows.2.826.g06c0f2f
   cpu: x86_64
   sizeof-long: 4

New Makefile variable HOST_CPU supports cross-compiling.

Suggested-by: Adric Norris <landstander668@gmail.com>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-14 22:52:49 -08:00
Jonathan Tan
ddd3e31242 decorate: clean up and document API
Improve the names of the identifiers in decorate.h, document them, and
add an example of how to use these functions.

The example is compiled and run as part of the test suite.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-08 09:16:27 -08:00
Junio C Hamano
4c6dad0059 Merge branch 'bw/protocol-v1'
A new mechanism to upgrade the wire protocol in place is proposed
and demonstrated that it works with the older versions of Git
without harming them.

* bw/protocol-v1:
  Documentation: document Extra Parameters
  ssh: introduce a 'simple' ssh variant
  i5700: add interop test for protocol transition
  http: tell server that the client understands v1
  connect: tell server that the client understands v1
  connect: teach client to recognize v1 server response
  upload-pack, receive-pack: introduce protocol version 1
  daemon: recognize hidden request arguments
  protocol: introduce protocol extension mechanisms
  pkt-line: add packet_write function
  connect: in ref advertisement, shallows are last
2017-12-06 09:23:44 -08:00
Thomas Gummerer
7c85a87c54 checkout: factor out functions to new lib file
Factor the functions out, so they can be re-used from other places.  In
particular these functions will be re-used in builtin/worktree.c to make
git worktree add dwim more.

While there add some docs to the function.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-27 09:48:06 +09:00
Jeff Hostetler
25ec7bcac0 list-objects: filter objects in traverse_commit_list
Create traverse_commit_list_filtered() and add filtering
interface to allow certain objects to be omitted from the
traversal.

Update traverse_commit_list() to be a wrapper for the above
with a null filter to minimize the number of callers that
needed to be changed.

Object filtering will be used in a future commit by rev-list
and pack-objects for partial clone and fetch to omit unwanted
objects from the result.

traverse_bitmap_commit_list() does not work with filtering.
If a packfile bitmap is present, it will not be used.  It
should be possible to extend such support in the future (at
least to simple filters that do not require object pathnames),
but that is beyond the scope of this patch series.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-22 14:11:57 +09:00
Junio C Hamano
e05336bdda Merge branch 'bp/fsmonitor'
We learned to talk to watchman to speed up "git status" and other
operations that need to see which paths have been modified.

* bp/fsmonitor:
  fsmonitor: preserve utf8 filenames in fsmonitor-watchman log
  fsmonitor: read entirety of watchman output
  fsmonitor: MINGW support for watchman integration
  fsmonitor: add a performance test
  fsmonitor: add a sample integration script for Watchman
  fsmonitor: add test cases for fsmonitor extension
  split-index: disable the fsmonitor extension when running the split index test
  fsmonitor: add a test tool to dump the index extension
  update-index: add fsmonitor support to update-index
  ls-files: Add support in ls-files to display the fsmonitor valid bit
  fsmonitor: add documentation for the fsmonitor extension.
  fsmonitor: teach git to optionally utilize a file system monitor to speed up detecting new or changed files.
  update-index: add a new --force-write-index option
  preload-index: add override to enable testing preload-index
  bswap: add 64 bit endianness helper get_be64
2017-11-21 14:07:50 +09:00
Junio C Hamano
d3e32dc90c Merge branch 'js/mingw-full-version-in-resources'
MinGW updates.

* js/mingw-full-version-in-resources:
  mingw: include the full version information in the resources
2017-11-09 14:31:31 +09:00
Johannes Schindelin
39bb86b4e5 mingw: include the full version information in the resources
This fixes https://github.com/git-for-windows/git/issues/723

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-01 13:43:52 +09:00
Brandon Williams
373d70efb2 protocol: introduce protocol extension mechanisms
Create protocol.{c,h} and provide functions which future servers and
clients can use to determine which protocol to use or is being used.

Also introduce the 'GIT_PROTOCOL' environment variable which will be
used to communicate a colon separated list of keys with optional values
to a server.  Unknown keys and values must be tolerated.  This mechanism
is used to communicate which version of the wire protocol a client would
like to use with a server.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-17 10:51:29 +09:00
Junio C Hamano
54bd705a95 Merge branch 'jt/oidmap'
Introduce a new "oidmap" API and rewrite oidset to use it.

* jt/oidmap:
  oidmap: map with OID as key
2017-10-11 14:52:22 +09:00
Junio C Hamano
1a2e1a76ec Merge branch 'mh/mmap-packed-refs'
Operations that do not touch (majority of) packed refs have been
optimized by making accesses to packed-refs file lazy; we no longer
pre-parse everything, and an access to a single ref in the
packed-refs does not touch majority of irrelevant refs, either.

* mh/mmap-packed-refs: (21 commits)
  packed-backend.c: rename a bunch of things and update comments
  mmapped_ref_iterator: inline into `packed_ref_iterator`
  ref_cache: remove support for storing peeled values
  packed_ref_store: get rid of the `ref_cache` entirely
  ref_store: implement `refs_peel_ref()` generically
  packed_read_raw_ref(): read the reference from the mmapped buffer
  packed_ref_iterator_begin(): iterate using `mmapped_ref_iterator`
  read_packed_refs(): ensure that references are ordered when read
  packed_ref_cache: keep the `packed-refs` file mmapped if possible
  packed-backend.c: reorder some definitions
  mmapped_ref_iterator_advance(): no peeled value for broken refs
  mmapped_ref_iterator: add iterator over a packed-refs file
  packed_ref_cache: remember the file-wide peeling state
  read_packed_refs(): read references with minimal copying
  read_packed_refs(): make parsing of the header line more robust
  read_packed_refs(): only check for a header at the top of the file
  read_packed_refs(): use mmap to read the `packed-refs` file
  die_unterminated_line(), die_invalid_line(): new functions
  packed_ref_cache: add a backlink to the associated `packed_ref_store`
  prefix_ref_iterator: break when we leave the prefix
  ...
2017-10-03 15:42:50 +09:00
Ben Peart
14527b3002 fsmonitor: add a performance test
Add a test utility (test-drop-caches) that flushes all changes to disk
then drops file system cache on Windows, Linux, and OSX.

Add a perf test (p7519-fsmonitor.sh) for fsmonitor.

By default, the performance test will utilize the Watchman file system
monitor if it is installed.  If Watchman is not installed, it will use a
dummy integration script that does not report any new or modified files.
The dummy script has very little overhead which provides optimistic results.

The performance test will also use the untracked cache feature if it is
available as fsmonitor uses it to speed up scanning for untracked files.

There are 4 environment variables that can be used to alter the default
behavior of the performance test:

GIT_PERF_7519_UNTRACKED_CACHE: used to configure core.untrackedCache
GIT_PERF_7519_SPLIT_INDEX: used to configure core.splitIndex
GIT_PERF_7519_FSMONITOR: used to configure core.fsmonitor
GIT_PERF_7519_DROP_CACHE: if set, the OS caches are dropped between tests

The big win for using fsmonitor is the elimination of the need to scan the
working directory looking for changed and untracked files. If the file
information is all cached in RAM, the benefits are reduced.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-01 17:23:05 +09:00
Ben Peart
dd3551f491 fsmonitor: add a test tool to dump the index extension
Add a test utility (test-dump-fsmonitor) that will dump the fsmonitor
index extension.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-01 17:23:05 +09:00
Ben Peart
883e248b8a fsmonitor: teach git to optionally utilize a file system monitor to speed up detecting new or changed files.
When the index is read from disk, the fsmonitor index extension is used
to flag the last known potentially dirty index entries. The registered
core.fsmonitor command is called with the time the index was last
updated and returns the list of files changed since that time. This list
is used to flag any additional dirty cache entries and untracked cache
directories.

We can then use this valid state to speed up preload_index(),
ie_match_stat(), and refresh_cache_ent() as they do not need to lstat()
files to detect potential changes for those entries marked
CE_FSMONITOR_VALID.

In addition, if the untracked cache is turned on valid_cached_dir() can
skip checking directories for new or changed files as fsmonitor will
invalidate the cache only for those directories that have been
identified as having potential changes.

To keep the CE_FSMONITOR_VALID state accurate during git operations;
when git updates a cache entry to match the current state on disk,
it will now set the CE_FSMONITOR_VALID bit.

Inversely, anytime git changes a cache entry, the CE_FSMONITOR_VALID bit
is cleared and the corresponding untracked cache directory is marked
invalid.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-01 17:23:01 +09:00
Jonathan Tan
9e6fabde82 oidmap: map with OID as key
This is similar to using the hashmap in hashmap.c, but with an
easier-to-use API. In particular, custom entry comparisons no longer
need to be written, and lookups can be done without constructing a
temporary entry structure.

This is implemented as a thin wrapper over the hashmap API. In
particular, this means that there is an additional 4-byte overhead due
to the fact that the first 4 bytes of the hash is redundantly stored.
For now, I'm taking the simpler approach, but if need be, we can
reimplement oidmap without affecting the callers significantly.

oidset has been updated to use oidmap.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-01 17:18:03 +09:00
Michael Haggerty
5b633610ec packed_ref_cache: keep the packed-refs file mmapped if possible
Keep a copy of the `packed-refs` file contents in memory for as long
as a `packed_ref_cache` object is in use:

* If the system allows it, keep the `packed-refs` file mmapped.

* If not (either because the system doesn't support `mmap()` at all,
  or because a file that is currently mmapped cannot be replaced via
  `rename()`), then make a copy of the file's contents in
  heap-allocated space, and keep that around instead.

We base the choice of behavior on a new build-time switch,
`MMAP_PREVENTS_DELETE`. By default, this switch is set for Windows
variants.

After this commit, `MMAP_NONE` and `MMAP_TEMPORARY` are still handled
identically. But the next commit will introduce a difference.

This whole change is still pointless, because we only read the
`packed-refs` file contents immediately after instantiating the
`packed_ref_cache`. But that will soon change.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-25 18:02:45 +09:00
Junio C Hamano
a36f631ad6 Merge branch 'bw/git-clang-format'
"make style" runs git-clang-format to help developers by pointing
out coding style issues.

* bw/git-clang-format:
  Makefile: add style build rule
  clang-format: outline the git project's coding style
2017-09-25 15:24:08 +09:00
Junio C Hamano
09595ab381 Merge branch 'jk/leak-checkers'
Many of our programs consider that it is OK to release dynamic
storage that is used throughout the life of the program by simply
exiting, but this makes it harder to leak detection tools to avoid
reporting false positives.  Plug many existing leaks and introduce
a mechanism for developers to mark that the region of memory
pointed by a pointer is not lost/leaking to help these tools.

* jk/leak-checkers:
  add UNLEAK annotation for reducing leak false positives
  set_git_dir: handle feeding gitdir to itself
  repository: free fields before overwriting them
  reset: free allocated tree buffers
  reset: make tree counting less confusing
  config: plug user_config leak
  update-index: fix cache entry leak in add_one_file()
  add: free leaked pathspec after add_files_to_cache()
  test-lib: set LSAN_OPTIONS to abort by default
  test-lib: --valgrind should not override --verbose-log
2017-09-19 10:47:55 +09:00
Junio C Hamano
cb6ec86d29 Merge branch 'ti/external-sha1dc'
Platforms that ship with a separate sha1 with collision detection
library can link to it instead of using the copy we ship as part of
our source tree.

* ti/external-sha1dc:
  sha1dc: allow building with the external sha1dc library
  sha1dc: build git plumbing code more explicitly
2017-09-19 10:47:50 +09:00
Junio C Hamano
8134746d1d Merge branch 'jn/vcs-svn-cleanup' into maint
Code clean-up.

* jn/vcs-svn-cleanup:
  vcs-svn: move remaining repo_tree functions to fast_export.h
  vcs-svn: remove repo_delete wrapper function
  vcs-svn: remove custom mode constants
  vcs-svn: remove more unused prototypes and declarations
2017-09-10 17:03:09 +09:00
Jeff King
0e5bba53af add UNLEAK annotation for reducing leak false positives
It's a common pattern in git commands to allocate some
memory that should last for the lifetime of the program and
then not bother to free it, relying on the OS to throw it
away.

This keeps the code simple, and it's fast (we don't waste
time traversing structures or calling free at the end of the
program). But it also triggers warnings from memory-leak
checkers like valgrind or LSAN. They know that the memory
was still allocated at program exit, but they don't know
_when_ the leaked memory stopped being useful. If it was
early in the program, then it's probably a real and
important leak. But if it was used right up until program
exit, it's not an interesting leak and we'd like to suppress
it so that we can see the real leaks.

This patch introduces an UNLEAK() macro that lets us do so.
To understand its design, let's first look at some of the
alternatives.

Unfortunately the suppression systems offered by
leak-checking tools don't quite do what we want. A
leak-checker basically knows two things:

  1. Which blocks were allocated via malloc, and the
     callstack during the allocation.

  2. Which blocks were left un-freed at the end of the
     program (and which are unreachable, but more on that
     later).

Their suppressions work by mentioning the function or
callstack of a particular allocation, and marking it as OK
to leak.  So imagine you have code like this:

  int cmd_foo(...)
  {
	/* this allocates some memory */
	char *p = some_function();
	printf("%s", p);
	return 0;
  }

You can say "ignore allocations from some_function(),
they're not leaks". But that's not right. That function may
be called elsewhere, too, and we would potentially want to
know about those leaks.

So you can say "ignore the callstack when main calls
some_function".  That works, but your annotations are
brittle. In this case it's only two functions, but you can
imagine that the actual allocation is much deeper. If any of
the intermediate code changes, you have to update the
suppression.

What we _really_ want to say is that "the value assigned to
p at the end of the function is not a real leak". But
leak-checkers can't understand that; they don't know about
"p" in the first place.

However, we can do something a little bit tricky if we make
some assumptions about how leak-checkers work. They
generally don't just report all un-freed blocks. That would
report even globals which are still accessible when the
leak-check is run.  Instead they take some set of memory
(like BSS) as a root and mark it as "reachable". Then they
scan the reachable blocks for anything that looks like a
pointer to a malloc'd block, and consider that block
reachable. And then they scan those blocks, and so on,
transitively marking anything reachable from a global as
"not leaked" (or at least leaked in a different category).

So we can mark the value of "p" as reachable by putting it
into a variable with program lifetime. One way to do that is
to just mark "p" as static. But that actually affects the
run-time behavior if the function is called twice (you
aren't likely to call main() twice, but some of our cmd_*()
functions are called from other commands).

Instead, we can trick the leak-checker by putting the value
into _any_ reachable bytes. This patch keeps a global
linked-list of bytes copied from "unleaked" variables. That
list is reachable even at program exit, which confers
recursive reachability on whatever values we unleak.

In other words, you can do:

  int cmd_foo(...)
  {
	char *p = some_function();
	printf("%s", p);
	UNLEAK(p);
	return 0;
  }

to annotate "p" and suppress the leak report.

But wait, couldn't we just say "free(p)"? In this toy
example, yes. But UNLEAK()'s byte-copying strategy has
several advantages over actually freeing the memory:

  1. It's recursive across structures. In many cases our "p"
     is not just a pointer, but a complex struct whose
     fields may have been allocated by a sub-function. And
     in some cases (e.g., dir_struct) we don't even have a
     function which knows how to free all of the struct
     members.

     By marking the struct itself as reachable, that confers
     reachability on any pointers it contains (including those
     found in embedded structs, or reachable by walking
     heap blocks recursively.

  2. It works on cases where we're not sure if the value is
     allocated or not. For example:

       char *p = argc > 1 ? argv[1] : some_function();

     It's safe to use UNLEAK(p) here, because it's not
     freeing any memory. In the case that we're pointing to
     argv here, the reachability checker will just ignore
     our bytes.

  3. Likewise, it works even if the variable has _already_
     been freed. We're just copying the pointer bytes. If
     the block has been freed, the leak-checker will skip
     over those bytes as uninteresting.

  4. Because it's not actually freeing memory, you can
     UNLEAK() before we are finished accessing the variable.
     This is helpful in cases like this:

       char *p = some_function();
       return another_function(p);

     Writing this with free() requires:

       int ret;
       char *p = some_function();
       ret = another_function(p);
       free(p);
       return ret;

     But with unleak we can just write:

       char *p = some_function();
       UNLEAK(p);
       return another_function(p);

This patch adds the UNLEAK() macro and enables it
automatically when Git is compiled with SANITIZE=leak.  In
normal builds it's a noop, so we pay no runtime cost.

It also adds some UNLEAK() annotations to show off how the
feature works. On top of other recent leak fixes, these are
enough to get t0000 and t0001 to pass when compiled with
LSAN.

Note the case in commit.c which actually converts a
strbuf_release() into an UNLEAK. This code was already
non-leaky, but the free didn't do anything useful, since
we're exiting. Converting it to an annotation means that
non-leak-checking builds pay no runtime cost. The cost is
minimal enough that it's probably not worth going on a
crusade to convert these kinds of frees to UNLEAKS. I did it
here for consistency with the "sb" leak (though it would
have been equally correct to go the other way, and turn them
both into strbuf_release() calls).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-08 15:43:17 +09:00
Junio C Hamano
eabdcd4ab4 Merge branch 'jt/packmigrate'
Code movement to make it easier to hack later.

* jt/packmigrate: (23 commits)
  pack: move for_each_packed_object()
  pack: move has_pack_index()
  pack: move has_sha1_pack()
  pack: move find_pack_entry() and make it global
  pack: move find_sha1_pack()
  pack: move find_pack_entry_one(), is_pack_valid()
  pack: move check_pack_index_ptr(), nth_packed_object_offset()
  pack: move nth_packed_object_{sha1,oid}
  pack: move clear_delta_base_cache(), packed_object_info(), unpack_entry()
  pack: move unpack_object_header()
  pack: move get_size_from_delta()
  pack: move unpack_object_header_buffer()
  pack: move {,re}prepare_packed_git and approximate_object_count
  pack: move install_packed_git()
  pack: move add_packed_git()
  pack: move unuse_pack()
  pack: move use_pack()
  pack: move pack-closing functions
  pack: move release_pack_memory()
  pack: move open_pack_index(), parse_pack_index()
  ...
2017-08-26 22:55:09 -07:00
Junio C Hamano
030faf2fa5 Merge branch 'kw/write-index-reduce-alloc'
We used to spend more than necessary cycles allocating and freeing
piece of memory while writing each index entry out.  This has been
optimized.

* kw/write-index-reduce-alloc:
  read-cache: avoid allocating every ondisk entry when writing
  read-cache: fix memory leak in do_write_index
  perf: add test for writing the index
2017-08-26 22:55:08 -07:00
Junio C Hamano
18c88f9af6 Merge branch 'jn/vcs-svn-cleanup'
Code clean-up.

* jn/vcs-svn-cleanup:
  vcs-svn: move remaining repo_tree functions to fast_export.h
  vcs-svn: remove repo_delete wrapper function
  vcs-svn: remove custom mode constants
  vcs-svn: remove more unused prototypes and declarations
2017-08-26 22:55:06 -07:00
Jonathan Tan
4f39cd821d pack: move pack name-related functions
Currently, sha1_file.c and cache.h contain many functions, both related
to and unrelated to packfiles. This makes both files very large and
causes an unclear separation of concerns.

Create a new file, packfile.c, to hold all packfile-related functions
currently in sha1_file.c. It has a corresponding header packfile.h.

In this commit, the pack name-related functions are moved. Subsequent
commits will move the other functions.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-23 15:12:06 -07:00
Jonathan Nieder
b8f43b120b vcs-svn: move remaining repo_tree functions to fast_export.h
These used to be for manipulating the in-memory repo_tree structure,
but nowadays they are convenience wrappers to handle a few git-vs-svn
mismatches:

 1. Git does not track empty directories but Subversion does.  When
    looking up a path in git that Subversion thinks exists and finding
    nothing, we can safely assume that the path represents a
    directory.  This is needed when a later Subversion revision
    modifies that directory.

 2. Subversion allows deleting a file by copying.  In Git fast-import
    we have to handle that more explicitly as a deletion.

These are details of the tool's interaction with git fast-import.
Move them to fast_export.c, where other such details are handled.

This way the function names do not start with a repo_ prefix that
would clash with the repository object introduced in
v2.14.0-rc0~38^2~16 (repository: introduce the repository object,
2017-06-22) or an svn_ prefix that would clash with libsvn (in case
someone wants to link this code with libsvn some day).

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-23 10:41:26 -07:00
Junio C Hamano
44c2339e55 Merge branch 'mh/packed-ref-store'
The "ref-store" code reorganization continues.

* mh/packed-ref-store: (32 commits)
  files-backend: cheapen refname_available check when locking refs
  packed_ref_store: handle a packed-refs file that is a symlink
  read_packed_refs(): die if `packed-refs` contains bogus data
  t3210: add some tests of bogus packed-refs file contents
  repack_without_refs(): don't lock or unlock the packed refs
  commit_packed_refs(): remove call to `packed_refs_unlock()`
  clear_packed_ref_cache(): don't protest if the lock is held
  packed_refs_unlock(), packed_refs_is_locked(): new functions
  packed_refs_lock(): report errors via a `struct strbuf *err`
  packed_refs_lock(): function renamed from lock_packed_refs()
  commit_packed_refs(): use a staging file separate from the lockfile
  commit_packed_refs(): report errors rather than dying
  packed_ref_store: make class into a subclass of `ref_store`
  packed-backend: new module for handling packed references
  packed_read_raw_ref(): new function, replacing `resolve_packed_ref()`
  packed_ref_store: support iteration
  packed_peel_ref(): new function, extracted from `files_peel_ref()`
  repack_without_refs(): take a `packed_ref_store *` parameter
  get_packed_ref(): take a `packed_ref_store *` parameter
  rollback_packed_refs(): take a `packed_ref_store *` parameter
  ...
2017-08-22 10:29:16 -07:00
Kevin Willford
3921a0b3c3 perf: add test for writing the index
A performance test for writing the index to be able to
determine if changes to allocating ondisk structure help.

Signed-off-by: Kevin Willford <kewillf@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-21 15:56:53 -07:00
Takashi Iwai
3964cbbb5c sha1dc: allow building with the external sha1dc library
Some distros provide SHA1 collision-detect code as a shared library.
It's the same code as we have in git tree (but may be with a different
init default for hash), and git can link with it as well; at least, it
may make maintenance easier, according to our security guys.

This patch allows user to build git linking with the external sha1dc
library instead of the built-in code.  User needs to define
DC_SHA1_EXTERNAL explicitly.  As default without it, the built-in
sha1dc code is used like before.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-16 14:44:25 -07:00
Takashi Iwai
36f048c5e4 sha1dc: build git plumbing code more explicitly
The plumbing code between sha1dc and git is defined in
sha1dc_git.[ch], but these aren't compiled / included directly but
only via the indirect inclusion from sha1dc code.  This is slightly
confusing when you try to trace the build flow.

This patch brings the following changes for simplification:

  - Make sha1dc_git.c stand-alone and build from Makefile

  - sha1dc_git.h is the common header to include further sha1.h
    depending on the build condition

  - Move comments for plumbing codes from the header to definitions

This is also meant as a preliminary work for further plumbing with
external sha1dc shlib.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-16 14:43:59 -07:00
Brandon Williams
2118805b92 Makefile: add style build rule
Add the 'style' build rule which will run git-clang-format on the diff
between HEAD and the current worktree.  The result is a diff of
suggested changes.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-14 15:26:22 -07:00
Junio C Hamano
a491307448 Merge branch 'jc/po-pritime-fix'
We started using "%" PRItime, imitating "%" PRIuMAX and friends, as
a way to format the internal timestamp value, but this does not
play well with gettext(1) i18n framework, and causes "make pot"
that is run by the l10n coordinator to create a broken po/git.pot
file.  This is a possible workaround for that problem.

* jc/po-pritime-fix:
  Makefile: help gettext tools to cope with our custom PRItime format
2017-07-21 14:57:37 -07:00
Junio C Hamano
e4efb39555 Merge branch 'jk/build-with-asan'
A recent update made it easier to use "-fsanitize=" option while
compiling but supported only one sanitize option.  Allow more than
one to be combined, joined with a comma, like "make SANITIZE=foo,bar".

* jk/build-with-asan:
  Makefile: allow combining UBSan with other sanitizers
2017-07-20 16:29:59 -07:00
Junio C Hamano
fc0fd5b23b Makefile: help gettext tools to cope with our custom PRItime format
We started using our own timestamp_t type and PRItime format
specifier to go along with it, so that we can later change the
underlying type and output format more easily, but this does not
play well with gettext tools.

Because gettext tools need to keep the *.po file portable across
platforms, they have to special-case the format specifiers like
PRIuMAX that are known types in inttypes.h, instead of letting CPP
handle strings like

    "%" PRIuMAX " seconds ago"

as an ordinary string concatenation.  They fundamentally cannot do
the same for our own custom type/format.

Given that po/git.pot needs to be generated only once every release
and by only one person, i.e. the l10n coordinator, let's update the
Makefile rule to generate po/git.pot so that gettext tools are run
on a munged set of sources in which all mentions of PRItime are
replaced with PRIuMAX, which is what we happen to use right now.

This way, developers do not have to care that PRItime does not play
well with gettext, and translators do not have to care that we use
our own PRItime.

The credit for the idea to munge the source files goes to Dscho.
Possible bugs are mine.

Helped-by: Jiang Xin <worldhello.net@gmail.com>
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-20 12:21:18 -07:00
René Scharfe
425ca6710b Makefile: allow combining UBSan with other sanitizers
Multiple sanitizers can be specified as a comma-separated list.  Set
the flag NO_UNALIGNED_LOADS even if UndefinedBehaviorSanitizer is not
the only sanitizer to build with.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-17 14:50:27 -07:00
Junio C Hamano
757e9874be Merge branch 'jk/build-with-asan'
The build procedure has been improved to allow building and testing
Git with address sanitizer more easily.

* jk/build-with-asan:
  Makefile: disable unaligned loads with UBSan
  Makefile: turn off -fomit-frame-pointer with sanitizers
  Makefile: add helper for compiling with -fsanitize
  test-lib: turn on ASan abort_on_error by default
  test-lib: set ASAN_OPTIONS variable before we run git
2017-07-13 16:14:54 -07:00
Junio C Hamano
2db87328ef Merge branch 'ab/sha1dc'
The "collission-detecting" implementation of SHA-1 hash we borrowed
from is replaced by directly binding the upstream project as our
submodule.  Glitches on minority platforms are still being worked out.

* ab/sha1dc:
  sha1collisiondetection: automatically enable when submodule is populated
  sha1dc: optionally use sha1collisiondetection as a submodule
2017-07-10 13:42:51 -07:00
Jeff King
566cf0b3bd Makefile: disable unaligned loads with UBSan
The undefined behavior sanitizer complains about unaligned
loads, even if they're OK for a particular platform in
practice. It's possible that they _are_ a problem, of
course, but since it's a known tradeoff the UBSan errors are
just noise.

Let's quiet it automatically by building with
NO_UNALIGNED_LOADS when SANITIZE=undefined is in use.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:31 -07:00
Jeff King
ddbc8a6d3e Makefile: turn off -fomit-frame-pointer with sanitizers
The ASan manual recommends disabling this optimization, as
it can make the backtraces produced by the tool harder to
follow (and since this is a test-debug build, we don't care
about squeezing out every last drop of performance).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:30 -07:00
Jeff King
56b5db30d0 Makefile: add helper for compiling with -fsanitize
You can already build and test with ASan by doing:

  make CFLAGS=-fsanitize=address test

but there are a few slight annoyances:

  1. It's a little long to type.

  2. It override your CFLAGS completely. You'd probably
     still want -O2, for instance.

  3. It's a good idea to also turn off "recovery", which
     lets the program keep running after a problem is
     detected (with the intention of finding as many bugs as
     possible in a given run). Since Git's test suite should
     generally run without triggering any problems, it's
     better to abort immediately and fail the test when we
     do find an issue.

With this patch, all of that happens automatically when you
run:

  make SANITIZE=address test

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:29 -07:00
Junio C Hamano
85ce4a6828 Merge branch 'bw/repo-object'
Introduce a "repository" object to eventually make it easier to
work in multiple repositories (the primary focus is to work with
the superproject and its submodules) in a single process.

* bw/repo-object:
  ls-files: use repository object
  repository: enable initialization of submodules
  submodule: convert is_submodule_initialized to work on a repository
  submodule: add repo_read_gitmodules
  submodule-config: store the_submodule_cache in the_repository
  repository: add index_state to struct repo
  config: read config from a repository object
  path: add repo_worktree_path and strbuf_repo_worktree_path
  path: add repo_git_path and strbuf_repo_git_path
  path: worktree_git_path() should not use file relocation
  path: convert do_git_path to take a 'struct repository'
  path: convert strbuf_git_common_path to take a 'struct repository'
  path: always pass in commondir to update_common_dir
  path: create path.h
  environment: store worktree in the_repository
  environment: place key repository state in the_repository
  repository: introduce the repository object
  environment: remove namespace_len variable
  setup: add comment indicating a hack
  setup: don't perform lazy initialization of repository state
2017-07-05 13:32:56 -07:00
Junio C Hamano
cac87dc01d sha1collisiondetection: automatically enable when submodule is populated
If a user wants to experiment with the version of collision
detecting sha1 from the submodule, the user needed to not just
populate the submodule but also needed to turn the knob.

A Makefile trick is easy enough to do so, so let's do this.  When
somebody with a copy of the submodule populated wants not to use it,
that can be done by overriding it in config.mak or from the command
line.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-03 10:09:37 -07:00
Ævar Arnfjörð Bjarmason
86cfd61e6b sha1dc: optionally use sha1collisiondetection as a submodule
Add an option to use the sha1collisiondetection library from the
submodule in sha1collisiondetection/ instead of in the copy in the
sha1dc/ directory.

This allows us to try out the submodule in sha1collisiondetection
without breaking the build for anyone who's not expecting them as we
work out any kinks.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-03 10:09:34 -07:00
Brandon Williams
359efeffc1 repository: introduce the repository object
Introduce the repository object 'struct repository' which can be used to
hold all state pertaining to a git repository.

Some of the benefits of object-ifying a repository are:

  1. Make the code base more readable and easier to reason about.

  2. Allow for working on multiple repositories, specifically
     submodules, within the same process.  Currently the process for
     working on a submodule involves setting up an argv_array of options
     for a particular command and then launching a child process to
     execute the command in the context of the submodule.  This is
     clunky and can require lots of little hacks in order to ensure
     correctness.  Ideally it would be nice to simply pass a repository
     and an options struct to a command.

  3. Eliminating reliance on global state will make it easier to
     enable the use of threading to improve performance.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-23 18:24:34 -07:00
Michael Haggerty
67be7c5a59 packed-backend: new module for handling packed references
Now that the interface between `files_ref_store` and
`packed_ref_store` is relatively narrow, move the latter into a new
module, "refs/packed-backend.h" and "refs/packed-backend.c". It still
doesn't quite implement the `ref_store` interface, but it will soon.

This commit moves code around and adjusts its visibility, but doesn't
change anything.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-23 13:27:32 -07:00