Commit Graph

300 Commits

Author SHA1 Message Date
Jeff King
c4ad00f8cc add object_as_type helper for casting objects
When we call lookup_commit, lookup_tree, etc, the logic goes
something like:

  1. Look for an existing object struct. If we don't have
     one, allocate and return a new one.

  2. Double check that any object we have is the expected
     type (and complain and return NULL otherwise).

  3. Convert an object with type OBJ_NONE (from a prior
     call to lookup_unknown_object) to the expected type.

We can encapsulate steps 2 and 3 in a helper function which
checks whether we have the expected object type, converts
OBJ_NONE as appropriate, and returns the object.

Not only does this shorten the code, but it also provides
one central location for converting OBJ_NONE objects into
objects of other types. Future patches will use that to
enforce type-specific invariants.

Since this is a refactoring, we would want it to behave
exactly as the current code. It takes a little reasoning to
see that this is the case:

  - for lookup_{commit,tree,etc} functions, we are just
    pulling steps 2 and 3 into a function that does the same
    thing.

  - for the call in peel_object, we currently only do step 3
    (but we want to consolidate it with the others, as
    mentioned above). However, step 2 is a noop here, as the
    surrounding conditional makes sure we have OBJ_NONE
    (which we want to keep to avoid an extraneous call to
    sha1_object_info).

  - for the call in lookup_commit_reference_gently, we are
    currently doing step 2 but not step 3. However, step 3
    is a noop here. The object we got will have just come
    from deref_tag, which must have figured out the type for
    each object in order to know when to stop peeling.
    Therefore the type will never be OBJ_NONE.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-28 10:14:33 -07:00
Jeff King
fe24d396e1 move setting of object->type to alloc_* functions
The "struct object" type implements basic object
polymorphism.  Individual instances are allocated as
concrete types (or as a union type that can store any
object), and a "struct object *" can be cast into its real
type after examining its "type" enum.  This means it is
dangerous to have a type field that does not match the
allocation (e.g., setting the type field of a "struct blob"
to "OBJ_COMMIT" would mean that a reader might read past the
allocated memory).

In most of the current code this is not a problem; the first
thing we do after allocating an object is usually to set its
type field by passing it to create_object. However, the
virtual commits we create in merge-recursive.c do not ever
get their type set. This does not seem to have caused
problems in practice, though (presumably because we always
pass around a "struct commit" pointer and never even look at
the type).

We can fix this oversight and also make it harder for future
code to get it wrong by setting the type directly in the
object allocation functions.

This will also make it easier to fix problems with commit
index allocation, as we know that any object allocated by
alloc_commit_node will meet the invariant that an object
with an OBJ_COMMIT type field will have a unique index
number.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-28 10:14:33 -07:00
Junio C Hamano
cfececfe1f Merge branch 'bg/xcalloc-nmemb-then-size' into maint
* bg/xcalloc-nmemb-then-size:
  transport-helper.c: rearrange xcalloc arguments
  remote.c: rearrange xcalloc arguments
  reflog-walk.c: rearrange xcalloc arguments
  pack-revindex.c: rearrange xcalloc arguments
  notes.c: rearrange xcalloc arguments
  imap-send.c: rearrange xcalloc arguments
  http-push.c: rearrange xcalloc arguments
  diff.c: rearrange xcalloc arguments
  config.c: rearrange xcalloc arguments
  commit.c: rearrange xcalloc arguments
  builtin/remote.c: rearrange xcalloc arguments
  builtin/ls-remote.c: rearrange xcalloc arguments
2014-07-22 10:25:17 -07:00
Jeff King
218aa3a616 reuse cached commit buffer when parsing signatures
When we call show_signature or show_mergetag, we read the
commit object fresh via read_sha1_file and reparse its
headers. However, in most cases we already have the object
data available, attached to the "struct commit". This is
partially laziness in dealing with the memory allocation
issues, but partially defensive programming, in that we
would always want to verify a clean version of the buffer
(not one that might have been munged by other users of the
commit).

However, we do not currently ever munge the commit buffer,
and not using the already-available buffer carries a fairly
big performance penalty when we are looking at a large
number of commits. Here are timings on linux.git:

  [baseline, no signatures]
  $ time git log >/dev/null
  real    0m4.902s
  user    0m4.784s
  sys     0m0.120s

  [before]
  $ time git log --show-signature >/dev/null
  real    0m14.735s
  user    0m9.964s
  sys     0m0.944s

  [after]
  $ time git log --show-signature >/dev/null
  real    0m9.981s
  user    0m5.260s
  sys     0m0.936s

Note that our user CPU time drops almost in half, close to
the non-signature case, but we do still spend more
wall-clock and system time, presumably from dealing with
gpg.

An alternative to this is to note that most commits do not
have signatures (less than 1% in this repo), yet we pay the
re-parsing cost for every commit just to find out if it has
a mergetag or signature. If we checked that when parsing the
commit initially, we could avoid re-examining most commits
later on. Even if we did pursue that direction, however,
this would still speed up the cases where we _do_ have
signatures. So it's probably worth doing either way.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:10:13 -07:00
Jeff King
8597ea3afe commit: record buffer length in cache
Most callsites which use the commit buffer try to use the
cached version attached to the commit, rather than
re-reading from disk. Unfortunately, that interface provides
only a pointer to the NUL-terminated buffer, with no
indication of the original length.

For the most part, this doesn't matter. People do not put
NULs in their commit messages, and the log code is happy to
treat it all as a NUL-terminated string. However, some code
paths do care. For example, when checking signatures, we
want to be very careful that we verify all the bytes to
avoid malicious trickery.

This patch just adds an optional "size" out-pointer to
get_commit_buffer and friends. The existing callers all pass
NULL (there did not seem to be any obvious sites where we
could avoid an immediate strlen() call, though perhaps with
some further refactoring we could).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:09:38 -07:00
Jeff King
c1b3c71f4b commit: convert commit->buffer to a slab
This will make it easier to manage the buffer cache
independently of the "struct commit" objects. It also
shrinks "struct commit" by one pointer, which may be
helpful.

Unfortunately it does not reduce the max memory size of
something like "rev-list", because rev-list uses
get_cached_commit_buffer() to decide not to show each
commit's output (and due to the design of slab_at, accessing
the slab requires us to extend it, allocating exactly the
same number of buffer pointers we dropped from the commit
structs).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:08:17 -07:00
Jeff King
ba41c1c93f use get_commit_buffer to avoid duplicate code
For both of these sites, we already do the "fallback to
read_sha1_file" trick. But we can shorten the code by just
using get_commit_buffer.

Note that the error cases are slightly different when
read_sha1_file fails. get_commit_buffer will die() if the
object cannot be loaded, or is a non-commit.

For get_sha1_oneline, this will almost certainly never
happen, as we will have just called parse_object (and if it
does, it's probably worth complaining about).

For record_author_date, the new behavior is probably better;
we notify the user of the error instead of silently ignoring
it. And because it's used only for sorting by author-date,
somebody examining a corrupt repo can fallback to the
regular traversal order.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:08:17 -07:00
Jeff King
152ff1cceb provide helpers to access the commit buffer
Many sites look at commit->buffer to get more detailed
information than what is in the parsed commit struct.
However, we sometimes drop commit->buffer to save memory,
in which case the caller would need to read the object
afresh. Some callers do this (leading to duplicated code),
and others do not (which opens the possibility of a segfault
if somebody else frees the buffer).

Let's provide a pair of helpers, "get" and "unuse", that let
callers easily get the buffer. They will use the cached
buffer when possible, and otherwise load from disk using
read_sha1_file.

Note that we also need to add a "get_cached" variant which
returns NULL when we do not have a cached buffer. At first
glance this seems to defeat the purpose of "get", which is
to always provide a return value. However, some log code
paths actually use the NULL-ness of commit->buffer as a
boolean flag to decide whether to try printing the
commit. At least for now, we want to continue supporting
that use.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:08:17 -07:00
Jeff King
66c2827ea4 provide a helper to set the commit buffer
Right now this is just a one-liner, but abstracting it will
make it easier to change later.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:08:17 -07:00
Jeff King
0fb370da9c provide a helper to free commit buffer
This converts two lines into one at each caller. But more
importantly, it abstracts the concept of freeing the buffer,
which will make it easier to change later.

Note that we also need to provide a "detach" mechanism for a
tricky case in index-pack. We are passed a buffer for the
object generated by processing the incoming pack. If we are
not using --strict, we just calculate the sha1 on that
buffer and return, leaving the caller to free it.  But if we
are using --strict, we actually attach that buffer to an
object, pass the object to the fsck functions, and then
detach the buffer from the object again (so that the caller
can free it as usual).  In this case, we don't want to free
the buffer ourselves, but just make sure it is no longer
associated with the commit.

Note that we are making the assumption here that the
attach/detach process does not impact the buffer at all
(e.g., it is never reallocated or modified). That holds true
now, and we have no plans to change that. However, as we
abstract the commit_buffer code, this dependency becomes
less obvious. So when we detach, let's also make sure that
we get back the same buffer that we gave to the
commit_buffer code.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:07:47 -07:00
Jeff King
969eba6341 commit: push commit_index update into alloc_commit_node
Whenever we create a commit object via lookup_commit, we
give it a unique index to be used with the commit-slab API.
The theory is that any "struct commit" we create would
follow this code path, so any such struct would get an
index. However, callers could use alloc_commit_node()
directly (and get multiple commits with index 0).

Let's push the indexing into alloc_commit_node so that it's
hard for callers to get it wrong.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-12 10:29:42 -07:00
Jeff King
3ffefb54c0 commit_tree: take a pointer/len pair rather than a const strbuf
While strbufs are pretty common throughout our code, it is
more flexible for functions to take a pointer/len pair than
a strbuf. It's easy to turn a strbuf into such a pair (by
dereferencing its members), but less easy to go the other
way (you can strbuf_attach, but that has implications about
memory ownership).

This patch teaches commit_tree (and its associated callers
and sub-functions) to take such a pair for the commit
message rather than a strbuf.  This makes passing the buffer
around slightly more verbose, but means we can get rid of
some dangerous strbuf_attach calls in the next patch.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-12 10:29:41 -07:00
Brian Gesiak
c4a7b0092b commit.c: rearrange xcalloc arguments
xcalloc() takes two arguments: the number of elements and their size.
reduce_heads() passes the arguments in reverse order, passing the
size of a commit*, followed by the number of commit* to be allocated.

Rearrange them so they are in the correct order.

Signed-off-by: Brian Gesiak <modocache@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-05-27 14:00:43 -07:00
Junio C Hamano
b407d40933 Merge branch 'nd/log-show-linear-break'
Attempts to show where a single-strand-of-pearls break in "git log"
output.

* nd/log-show-linear-break:
  log: add --show-linear-break to help see non-linear history
  object.h: centralize object flag allocation
2014-04-03 12:38:11 -07:00
Nguyễn Thái Ngọc Duy
208acbfb82 object.h: centralize object flag allocation
While the field "flags" is mainly used by the revision walker, it is
also used in many other places. Centralize the whole flag allocation to
one place for a better overview (and easier to move flags if we have
too).

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-25 15:09:24 -07:00
Junio C Hamano
fe9122a352 Merge branch 'dd/use-alloc-grow'
Replace open-coded reallocation with ALLOC_GROW() macro.

* dd/use-alloc-grow:
  sha1_file.c: use ALLOC_GROW() in pretend_sha1_file()
  read-cache.c: use ALLOC_GROW() in add_index_entry()
  builtin/mktree.c: use ALLOC_GROW() in append_to_tree()
  attr.c: use ALLOC_GROW() in handle_attr_line()
  dir.c: use ALLOC_GROW() in create_simplify()
  reflog-walk.c: use ALLOC_GROW()
  replace_object.c: use ALLOC_GROW() in register_replace_object()
  patch-ids.c: use ALLOC_GROW() in add_commit()
  diffcore-rename.c: use ALLOC_GROW()
  diff.c: use ALLOC_GROW()
  commit.c: use ALLOC_GROW() in register_commit_graft()
  cache-tree.c: use ALLOC_GROW() in find_subtree()
  bundle.c: use ALLOC_GROW() in add_to_ref_list()
  builtin/pack-objects.c: use ALLOC_GROW() in check_pbase_path()
2014-03-18 13:50:21 -07:00
Junio C Hamano
a8e1d711cc Merge branch 'dd/find-graft-with-sha1-pos'
Replace a hand-rolled binary search with a call to our generic
binary search helper function.

* dd/find-graft-with-sha1-pos:
  commit.c: use the generic "sha1_pos" function for lookup
2014-03-18 13:50:11 -07:00
Tanay Abhra
147972b1a6 commit.c: use skip_prefix() instead of starts_with()
In record_author_date() & parse_gpg_output(), the callers of
starts_with() not just want to know if the string starts with the
prefix, but also can benefit from knowing the string that follows
the prefix.

By using skip_prefix(), we can do both at the same time.

Helped-by: Max Horn <max@quendi.de>
Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-04 13:26:42 -08:00
Dmitry S. Dolzhenko
d6e82b575a commit.c: use ALLOC_GROW() in register_commit_graft()
Signed-off-by: Dmitry S. Dolzhenko <dmitrys.dolzhenko@yandex.ru>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-03 14:47:07 -08:00
Dmitry S. Dolzhenko
0a9136f327 commit.c: use the generic "sha1_pos" function for lookup
Refactor binary search in "commit_graft_pos" function: use
generic "sha1_pos" function.

Signed-off-by: Dmitry S. Dolzhenko <dmitrys.dolzhenko@yandex.ru>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-27 10:55:27 -08:00
Junio C Hamano
4243b2d1e4 Merge branch 'vm/octopus-merge-bases-simplify'
* vm/octopus-merge-bases-simplify:
  get_octopus_merge_bases(): cleanup redundant variable
2014-01-10 10:33:45 -08:00
Junio C Hamano
3b9d69ec22 Merge branch 'js/lift-parent-count-limit'
There is no reason to have a hardcoded upper limit of the number of
parents for an octopus merge, created via the graft mechanism.

* js/lift-parent-count-limit:
  Remove the line length limit for graft files
2014-01-10 10:33:36 -08:00
Junio C Hamano
34aacf30a3 Merge branch 'nd/commit-tree-constness'
Code clean-up.

* nd/commit-tree-constness:
  commit.c: make "tree" a const pointer in commit_tree*()
2014-01-10 10:33:13 -08:00
Vasily Makarov
6bc76725ea get_octopus_merge_bases(): cleanup redundant variable
pptr is needless. Some related code got cleaned as well.

Signed-off-by: Vasily Makarov <einmalfel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-01-03 10:29:03 -08:00
Johannes Schindelin
e228c1736f Remove the line length limit for graft files
Support for grafts predates Git's strbuf, and hence it is understandable
that there was a hard-coded line length limit of 1023 characters (which
was chosen a bit awkwardly, given that it is *exactly* one byte short of
aligning with the 41 bytes occupied by a commit name and the following
space or new-line character).

While regular commit histories hardly win comprehensibility in general
if they merge more than twenty-two branches in one go, it is not Git's
business to limit grafts in such a way.

In this particular developer's case, the use case that requires
substantially longer graft lines to be supported is the visualization of
the commits' order implied by their changes: commits are considered to
have an implicit relationship iff exchanging them in an interactive
rebase would result in merge conflicts.

Thusly implied branches tend to be very shallow in general, and the
resulting thicket of implied branches is usually very wide; It is
actually quite common that *most* of the commits in a topic branch have
not even one implied parent, so that a final merge commit has about as
many implied parents as there are commits in said branch.

[jc: squashed in tests by Jonathan]

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-27 16:46:25 -08:00
Nguyễn Thái Ngọc Duy
8785b7654b commit.c: make "tree" a const pointer in commit_tree*()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-26 11:55:18 -08:00
Junio C Hamano
ad70448576 Merge branch 'cc/starts-n-ends-with'
Remove a few duplicate implementations of prefix/suffix comparison
functions, and rename them to starts_with and ends_with.

* cc/starts-n-ends-with:
  replace {pre,suf}fixcmp() with {starts,ends}_with()
  strbuf: introduce starts_with() and ends_with()
  builtin/remote: remove postfixcmp() and use suffixcmp() instead
  environment: normalize use of prefixcmp() by removing " != 0"
2013-12-17 12:02:44 -08:00
Christian Couder
5955654823 replace {pre,suf}fixcmp() with {starts,ends}_with()
Leaving only the function definitions and declarations so that any
new topic in flight can still make use of the old functions, replace
existing uses of the prefixcmp() and suffixcmp() with new API
functions.

The change can be recreated by mechanically applying this:

    $ git grep -l -e prefixcmp -e suffixcmp -- \*.c |
      grep -v strbuf\\.c |
      xargs perl -pi -e '
        s|!prefixcmp\(|starts_with\(|g;
        s|prefixcmp\(|!starts_with\(|g;
        s|!suffixcmp\(|ends_with\(|g;
        s|suffixcmp\(|!ends_with\(|g;
      '

on the result of preparatory changes in this series.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-05 14:13:21 -08:00
Junio C Hamano
5bb62059f2 Merge branch 'jk/robustify-parse-commit'
* jk/robustify-parse-commit:
  checkout: do not die when leaving broken detached HEAD
  use parse_commit_or_die instead of custom message
  use parse_commit_or_die instead of segfaulting
  assume parse_commit checks for NULL commit
  assume parse_commit checks commit->object.parsed
  log_tree_diff: die when we fail to parse a commit
2013-12-05 12:54:01 -08:00
Jeff King
5e7d4d3e93 assume parse_commit checks for NULL commit
The parse_commit function will check whether it was passed a
NULL commit pointer, and if so, return an error. There is no
need for callers to check this separately.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-10-24 15:43:50 -07:00
Jeff King
7059dccc6c log_tree_diff: die when we fail to parse a commit
We currently call parse_commit and then assume we can
dereference the resulting "tree" struct field. If parsing
failed, however, that field is NULL and we end up
segfaulting.

Instead of a segfault, let's print an error message and die
a little more gracefully.

Note that this should never happen in practice, but may
happen in a corrupt repository.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-10-24 15:43:50 -07:00
Junio C Hamano
4ab4a6dfb4 Merge branch 'tr/log-full-diff-keep-true-parents'
Output from "git log --full-diff -- <pathspec>" looked strange,
because comparison was done with the previous ancestor that touched
the specified <pathspec>, causing the patches for paths outside the
pathspec to show more than the single commit has changed.

Tweak "git reflog -p" for the same reason using the same mechanism.

* tr/log-full-diff-keep-true-parents:
  log: use true parents for diff when walking reflogs
  log: use true parents for diff even when rewriting
2013-09-09 14:33:16 -07:00
Junio C Hamano
c8abf659f7 Merge branch 'bc/commit-invalid-utf8'
* bc/commit-invalid-utf8:
  commit: typofix for xxFFF[EF] check
2013-08-05 10:11:04 -07:00
Junio C Hamano
dc773a67e1 commit: typofix for xxFFF[EF] check
We wanted to catch all codepoints that ends with FFFE and FFFF,
not with 0FFFE and 0FFFF.

Noticed and corrected by Peter Krefting.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-08-05 09:53:38 -07:00
Thomas Rast
53d00b39ce log: use true parents for diff even when rewriting
When using pathspec filtering in combination with diff-based log
output, parent simplification happens before the diff is computed.
The diff is therefore against the *simplified* parents.

This works okay, arguably by accident, in the normal case:
simplification reduces to one parent as long as the commit is TREESAME
to it.  So the simplified parent of any given commit must have the
same tree contents on the filtered paths as its true (unfiltered)
parent.

However, --full-diff breaks this guarantee, and indeed gives pretty
spectacular results when comparing the output of

  git log --graph --stat ...
  git log --graph --full-diff --stat ...

(--graph internally kicks in parent simplification, much like
--parents).

To fix it, store a copy of the parent list before simplification (in a
slab) whenever --full-diff is in effect.  Then use the stored parents
instead of the simplified ones in the commit display code paths.  The
latter do not actually check for --full-diff to avoid duplicated code;
they just grab the original parents if save_parents() has not been
called for this revision walk.

For ordinary commits it should be obvious that this is the right thing
to do.

Merge commits are a bit subtle.  Observe that with default
simplification, merge simplification is an all-or-nothing decision:
either the merge is TREESAME to one parent and disappears, or it is
different from all parents and the parent list remains intact.
Redundant parents are not pruned, so the existing code also shows them
as a merge.

So if we do show a merge commit, the parent list just consists of the
rewrite result on each parent.  Running, e.g., --cc on this in
--full-diff mode is not very useful: if any commits were skipped, some
hunks will disagree with all sides of the merge (with one side,
because commits were skipped; with the others, because they didn't
have those changes in the first place).  This triggers --cc showing
these hunks spuriously.

Therefore I believe that even for merge commits it is better to show
the diffs wrt. the original parents.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-08-01 10:25:48 -07:00
Junio C Hamano
73f4c9a104 Merge branch 'bc/commit-invalid-utf8'
Logic to auto-detect character encodings in the commit log message
did not reject overlong and invalid UTF-8 characters.

* bc/commit-invalid-utf8:
  commit: reject non-characters
  commit: reject overlong UTF-8 sequences
  commit: reject invalid UTF-8 codepoints
2013-07-18 12:58:19 -07:00
Peter Krefting
81050ac604 commit: reject non-characters
Unicode clause D14 defines all characters U+nFFFE and U+nFFFF (where
0 <= n <= 10h) as well as the range U+FDD0..U+FDEF as non-characters,
reserved for internal use only.  Disallow these characters in commit
messages as they are normally not recommended for interchange.

Signed-off-by: Peter Krefting <peter@softwolves.pp.se>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-09 09:01:24 -07:00
brian m. carlson
e82bd6cc70 commit: reject overlong UTF-8 sequences
The commit code accepts pseudo-UTF-8 sequences that encode a character with more
bytes than necessary.  Reject such sequences, since they are not valid UTF-8.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-04 21:48:45 -07:00
brian m. carlson
28110d4bfc commit: reject invalid UTF-8 codepoints
The commit code already contains code for validating UTF-8, but it does not
check for invalid values, such as guaranteed non-characters and surrogates.  Fix
this by explicitly checking for and rejecting such characters.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-04 21:45:18 -07:00
Jeff King
727377ff65 commit.c: make compare_commits_by_commit_date global
This helper function was introduced as a prio_queue
comparator to help topological sorting. However, other users
of prio_queue who want to replace commit_list_insert_by_date
will want to use it, too. So let's make it public.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-02 12:03:50 -07:00
Junio C Hamano
534f0e0996 Merge branch 'jc/topo-author-date-sort'
"git log" learned the "--author-date-order" option, with which the
output is topologically sorted and commits in parallel histories
are shown intermixed together based on the author timestamp.

* jc/topo-author-date-sort:
  t6003: add --author-date-order test
  topology tests: teach a helper to set author dates as well
  t6003: add --date-order test
  topology tests: teach a helper to take abbreviated timestamps
  t/lib-t6000: style fixes
  log: --author-date-order
  sort-in-topological-order: use prio-queue
  prio-queue: priority queue of pointers to structs
  toposort: rename "lifo" field
2013-07-01 12:41:23 -07:00
Junio C Hamano
55f34c8d39 Merge branch 'jk/commit-info-slab'
Allow adding custom information to commit objects in order to
represent unbound number of flag bits etc.

* jk/commit-info-slab:
  commit-slab: introduce a macro to define a slab for new type
  commit-slab: avoid large realloc
  commit: allow associating auxiliary info on-demand
2013-07-01 12:41:19 -07:00
Junio C Hamano
81c6b38b67 log: --author-date-order
Sometimes people would want to view the commits in parallel
histories in the order of author dates, not committer dates.

Teach "topo-order" sort machinery to do so, using a commit-info slab
to record the author dates of each commit, and prio-queue to sort
them.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-11 15:15:21 -07:00
Junio C Hamano
da24b1044f sort-in-topological-order: use prio-queue
Use the prio-queue data structure to implement a priority queue of
commits sorted by committer date, when handling --date-order.  The
structure can also be used as a simple LIFO stack, which is a good
match for --topo-order processing.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-11 15:15:21 -07:00
Junio C Hamano
08f704f294 toposort: rename "lifo" field
The primary invariant of sort_in_topological_order() is that a
parent commit is not emitted until all children of it are.  When
traversing a forked history like this with "git log C E":

    A----B----C
     \
      D----E

we ensure that A is emitted after all of B, C, D, and E are done, B
has to wait until C is done, and D has to wait until E is done.

In some applications, however, we would further want to control how
these child commits B, C, D and E on two parallel ancestry chains
are shown.

Most of the time, we would want to see C and B emitted together, and
then E and D, and finally A (i.e. the --topo-order output).  The
"lifo" parameter of the sort_in_topological_order() function is used
to control this behaviour.  We start the traversal by knowing two
commits, C and E.  While keeping in mind that we also need to
inspect E later, we pick C first to inspect, and we notice and
record that B needs to be inspected.  By structuring the "work to be
done" set as a LIFO stack, we ensure that B is inspected next,
before other in-flight commits we had known that we will need to
inspect, e.g. E.

When showing in --date-order, we would want to see commits ordered
by timestamps, i.e. show C, E, B and D in this order before showing
A, possibly mixing commits from two parallel histories together.
When "lifo" parameter is set to false, the function keeps the "work
to be done" set sorted in the date order to realize this semantics.
After inspecting C, we add B to the "work to be done" set, but the
next commit we inspect from the set is E which is newer than B.

The name "lifo", however, is too strongly tied to the way how the
function implements its behaviour, and does not describe what the
behaviour _means_.

Replace this field with an enum rev_sort_order, with two possible
values: REV_SORT_IN_GRAPH_ORDER and REV_SORT_BY_COMMIT_DATE, and
update the existing code.  The mechanical replacement rule is:

  "lifo == 0" is equivalent to "sort_order == REV_SORT_BY_COMMIT_DATE"
  "lifo == 1" is equivalent to "sort_order == REV_SORT_IN_GRAPH_ORDER"

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-11 15:15:21 -07:00
Junio C Hamano
a84b794ad0 commit-slab: introduce a macro to define a slab for new type
Introduce a header file to define a macro that can define the struct
type, initializer, accessor and cleanup functions to manage a commit
slab.  Update the "indegree" topological sort facility using it.

To associate 32 flag bits with each commit, you can write:

	define_commit_slab(flag32, uint32);

to declare "struct flag32" type, define an instance of it with

	struct flag32 flags;

and initialize it by calling

	init_flag32(&flags);

After that, a call to flag32_at() function

	uint32 *fp = flag32_at(&flags, commit);

will return a pointer pointing at a uint32 for that commit.  Once
you are done with these flags, clean them up with

	clear_flag32(&flags);

Callers that cannot hard-code how wide the data to be associated
with the commit be at compile time can use the "_with_stride"
variant to initialize the slab.

Suppose you want to give one bit per existing ref, and paint commits
down to find which refs are descendants of each commit.  Saying

	typedef uint32 bits320[5];
	define_commit_slab(flagbits, bits320);

at compile time will still limit your code with hard-coded limit,
because you may find that you have more than 320 refs at runtime.

The code can declare a commit slab "struct flagbits" like this
instead:

	define_commit_slab(flagbits, unsigned char);
	struct flagbits flags;

and initialize it by:

	nrefs = ... count number of refs ...
	init_flagbits_with_stride(&flags, (nrefs + 7) / 8);

so that

	unsigned char *fp = flagbits_at(&flags, commit);

will return a pointer pointing at an array of 40 "unsigned char"s
associated with the commit, once you figure out nrefs is 320 at
runtime.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-07 10:02:12 -07:00
Junio C Hamano
66eb375d3d commit-slab: avoid large realloc
Instead of using a single "slab" and keep reallocating it as we find
that we need to deal with commits with larger values of commit->index,
make a "slab" an array of many "slab_piece"s. Each access may need
two levels of indirections, but we only need to reallocate the first
level array of pointers when we have to grow the table this way.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-13 22:15:42 -07:00
Jeff King
96c4f4a370 commit: allow associating auxiliary info on-demand
The "indegree" field in the commit object is only used while sorting
a list of commits in topological order, and wasting memory otherwise.

We would prefer to shrink the size of individual commit objects,
which we may have to hold thousands of in-core. We could eject
"indegree" field out from the commit object and represent it as a
dynamic table based on the decoration infrastructure, but the
decoration is meant for sparse annotation and is not a good match.

Instead, let's try a different approach.

 - Assign an integer (commit->index) to each commit we keep in-core
   (reuse the space of "indegree" field for it);

 - When running the topological sort, allocate an array of integers
   in bulk (called "slab"), use the commit->index as an index into
   this array, and store the "indegree" information there.

This does _not_ reduce the memory footprint of a commit object, but
the commit->index can be used as the index to dynamically associate
commits with other kinds of information as needed.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-13 21:50:54 -07:00
Junio C Hamano
caa7d79f1f Sync with 'maint'
* maint:
  Correct common spelling mistakes in comments and tests
  kwset: fix spelling in comments
  precompose-utf8: fix spelling of "want" in error message
  compat/nedmalloc: fix spelling in comments
  compat/regex: fix spelling and grammar in comments
  obstack: fix spelling of similar
  contrib/subtree: fix spelling of accidentally
  git-remote-mediawiki: spelling fixes
  doc: various spelling fixes
  fast-export: fix argument name in error messages
  Documentation: distinguish between ref and offset deltas in pack-format
  i18n: make the translation of -u advice in one go
2013-04-12 13:54:01 -07:00
Stefano Lattarini
41ccfdd9c9 Correct common spelling mistakes in comments and tests
Most of these were found using Lucas De Marchi's codespell tool.

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-12 13:38:40 -07:00