* mm/doc-hooks-linkgit-fix:
  Documentation: fix broken linkgit to git-config

Signed-off-by: NMatthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* es/st-add4-gcc-4.2-workaround:
  git-compat-util: st_add4: work around gcc 4.2.x compiler crash

Although changes by 5b442c4f (tree-diff: catch integer overflow in
combine_diff_path allocation, 2016-02-19) are perfectly valid, they
unfortunately trigger an internal compiler error in gcc 4.2.x:

    combine-diff.c: In function 'diff_tree_combined':
    combine-diff.c:1391: internal compiler error: Segmentation fault: 11

Experimentation reveals that changing st_add4()'s argument evaluation
order is sufficient to sidestep this problem.

Although st_add3() does not trigger the compiler bug, for style
consistency, change its argument evaluation order to match.
Signed-off-by: NEric Sunshine <sunshine@sunshineco.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* maint-2.6:
  Git 2.6.6
  Git 2.5.5
  Git 2.4.11

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* maint-2.5:
  Git 2.5.5
  Git 2.4.11
  list-objects: pass full pathname to callbacks
  list-objects: drop name_path entirely
  list-objects: convert name_path to a strbuf
  show_object_with_name: simplify by using path_name()
  http-push: stop using name_path
  tree-diff: catch integer overflow in combine_diff_path allocation
  add helpers for detecting size_t overflow

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* maint-2.4:
  Git 2.4.11
  list-objects: pass full pathname to callbacks
  list-objects: drop name_path entirely
  list-objects: convert name_path to a strbuf
  show_object_with_name: simplify by using path_name()
  http-push: stop using name_path
  tree-diff: catch integer overflow in combine_diff_path allocation
  add helpers for detecting size_t overflow

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Bugfix patches were backported from the 'master' front to plug heap
corruption holes, to catch integer overflow in the computation of
pathname lengths, and to get rid of the name_path API.  Both of
these would have resulted in writing over an under-allocated buffer
when formulating pathnames while tree traversal.

* jk/path-name-safety-2.4:
  list-objects: pass full pathname to callbacks
  list-objects: drop name_path entirely
  list-objects: convert name_path to a strbuf
  show_object_with_name: simplify by using path_name()
  http-push: stop using name_path
  tree-diff: catch integer overflow in combine_diff_path allocation
  add helpers for detecting size_t overflow

* jk/path-name-safety-2.7:
  list-objects: pass full pathname to callbacks
  list-objects: drop name_path entirely
  list-objects: convert name_path to a strbuf
  show_object_with_name: simplify by using path_name()
  http-push: stop using name_path
  tree-diff: catch integer overflow in combine_diff_path allocation
  add helpers for detecting size_t overflow

* jk/path-name-safety-2.6:
  list-objects: pass full pathname to callbacks
  list-objects: drop name_path entirely
  list-objects: convert name_path to a strbuf
  show_object_with_name: simplify by using path_name()
  http-push: stop using name_path
  tree-diff: catch integer overflow in combine_diff_path allocation
  add helpers for detecting size_t overflow

* jk/path-name-safety-2.5:
  list-objects: pass full pathname to callbacks
  list-objects: drop name_path entirely
  list-objects: convert name_path to a strbuf
  show_object_with_name: simplify by using path_name()
  http-push: stop using name_path
  tree-diff: catch integer overflow in combine_diff_path allocation
  add helpers for detecting size_t overflow

* jk/path-name-safety-2.4:
  list-objects: pass full pathname to callbacks
  list-objects: drop name_path entirely
  list-objects: convert name_path to a strbuf
  show_object_with_name: simplify by using path_name()
  http-push: stop using name_path
  tree-diff: catch integer overflow in combine_diff_path allocation
  add helpers for detecting size_t overflow

When we find a blob at "a/b/c", we currently pass this to
our show_object_fn callbacks as two components: "a/b/" and
"c". Callbacks which want the full value then call
path_name(), which concatenates the two. But this is an
inefficient interface; the path is a strbuf, and we could
simply append "c" to it temporarily, then roll back the
length, without creating a new copy.

So we could improve this by teaching the callsites of
path_name() this trick (and there are only 3). But we can
also notice that no callback actually cares about the
broken-down representation, and simply pass each callback
the full path "a/b/c" as a string. The callback code becomes
even simpler, then, as we do not have to worry about freeing
an allocated buffer, nor rolling back our modification to
the strbuf.

This is theoretically less efficient, as some callbacks
would not bother to format the final path component. But in
practice this is not measurable. Since we use the same
strbuf over and over, our work to grow it is amortized, and
we really only pay to memcpy a few bytes.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In the previous commit, we left name_path as a thin wrapper
around a strbuf. This patch drops it entirely. As a result,
every show_object_fn callback needs to be adjusted. However,
none of their code needs to be changed at all, because the
only use was to pass it to path_name(), which now handles
the bare strbuf.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The "struct name_path" data is examined in only two places:
we generate it in process_tree(), and we convert it to a
single string in path_name(). Everyone else just passes it
through to those functions.

We can further note that process_tree() already keeps a
single strbuf with the leading tree path, for use with
tree_entry_interesting().

Instead of building a separate name_path linked list, let's
just use the one we already build in "base". This reduces
the amount of code (especially tricky code in path_name()
which did not check for integer overflows caused by deep
or large pathnames).

It is also more efficient in some instances.  Any time we
were using tree_entry_interesting, we were building up the
strbuf anyway, so this is an immediate and obvious win
there. In cases where we were not, we trade off storing
"pathname/" in a strbuf on the heap for each level of the
path, instead of two pointers and an int on the stack (with
one pointer into the tree object). On a 64-bit system, the
latter is 20 bytes; so if path components are less than that
on average, this has lower peak memory usage.  In practice
it probably doesn't matter either way; we are already
holding in memory all of the tree objects leading up to each
pathname, and for normal-depth pathnames, we are only
talking about hundreds of bytes.

This patch leaves "struct name_path" as a thin wrapper
around the strbuf, to avoid disrupting callbacks. We should
fix them, but leaving it out makes this diff easier to view.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When "git rev-list" shows an object with its associated path
name, it does so by walking the name_path linked list and
printing each component (stopping at any embedded NULs or
newlines).

We'd like to eventually get rid of name_path entirely in
favor of a single buffer, and dropping this custom printing
code is part of that. As a first step, let's use path_name()
to format the list into a single buffer, and print that.
This is strictly less efficient than the original, but it's
a temporary step in the refactoring; our end game will be to
get the fully formatted name in the first place.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Performing computations on size_t variables that we feed to
xmalloc and friends can be dangerous, as an integer overflow
can cause us to allocate a much smaller chunk than we
realized.

We already have unsigned_add_overflows(), but let's add
unsigned_mult_overflows() to that. Furthermore, rather than
have each site manually check and die on overflow, we can
provide some helpers that will:

  - promote the arguments to size_t, so that we know we are
    doing our computation in the same size of integer that
    will ultimately be fed to xmalloc

  - check and die on overflow

  - return the result so that computations can be done in
    the parameter list of xmalloc.

These functions are a lot uglier to use than normal
arithmetic operators (you have to do "st_add(foo, bar)"
instead of "foo + bar"). To at least limit the damage, we
also provide multi-valued versions. So rather than:

  st_add(st_add(a, b), st_add(c, d));

you can write:

  st_add4(a, b, c, d);

This isn't nearly as elegant as a varargs function, but it's
a lot harder to get it wrong. You don't have to remember to
add a sentinel value at the end, and the compiler will
complain if you get the number of arguments wrong. This
patch adds only the numbered variants required to convert
the current code base; we can easily add more later if
needed.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The graph traversal code here passes along a name_path to
build up the pathname at which we find each blob. But we
never actually do anything with the resulting names, making
it a waste of code and memory.

This usage came in aa1dbc98 (Update http-push functionality,
2006-03-07), and originally the result was passed to
"add_object" (which stored it, but didn't really use it,
either). But we stopped using that function in 1f1e895f (Add
"named object array" concept, 2006-06-19) in favor of
storing just the objects themselves.

Moreover, the generation of the name in process_tree() is
buggy. It sticks "name" onto the end of the name_path linked
list, and then passes it down again as it recurses (instead
of "entry.path"). So it's a good thing this was unused, as
the resulting path for "a/b/c/d" would end up as "a/a/a/a".
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

A combine_diff_path struct has two "flex" members allocated
alongside the struct: a string to hold the pathname, and an
array of parent pointers. We use an "int" to compute this,
meaning we may easily overflow it if the pathname is
extremely long.

We can fix this by using size_t, and checking for overflow
with the st_add helper.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* ma/update-hooks-sample-typofix:
  templates/hooks: fix minor typo in the sample update-hook

* dt/initial-ref-xn-commit-doc:
  refs: document transaction semantics

* ps/plug-xdl-merge-leak:
  xdiff/xmerge: fix memory leak in xdl_merge

Code simplification.

* ak/git-strip-extension-from-dashed-command:
  git.c: simplify stripping extension of a file in handle_builtin()

Code simplification.

* ak/extract-argv0-last-dir-sep:
  exec_cmd.c: use find_last_dir_sep() for code simplification

The code to read the pack data using the offsets stored in the pack
idx file has been made more carefully check the validity of the
data in the idx.

* jk/pack-idx-corruption-safety:
  sha1_file.c: mark strings for translation
  use_pack: handle signed off_t overflow
  nth_packed_object_offset: bounds-check extended offset
  t5313: test bounds-checks of corrupted/malicious pack/idx files

"git config section.var value" to set a value in per-repository
configuration file failed when it was run outside any repository,
but didn't say the reason correctly.

* js/config-set-in-non-repository:
  git config: report when trying to modify a non-existing repo config

A helper function "git submodule" uses since v2.7.0 to list the
modules that match the pathspec argument given to its subcommands
(e.g. "submodule add <repo> <path>") has been fixed.

* sb/submodule-module-list-fix:
  submodule helper list: respect correct path prefix

Recent versions of GNU grep are pickier when their input contains
arbitrary binary data, which some of our tests uses.  Rewrite the
tests to sidestep the problem.

* jk/grep-binary-workaround-in-test:
  t9200: avoid grep on non-ASCII data
  t8005: avoid grep on non-ASCII data

The documentation did not clearly state that the 'simple' mode is
now the default for "git push" when push.default configuration is
not set.

* mm/push-simple-doc:
  Documentation/git-push: document that 'simple' is the default

* jk/tighten-alloc: (23 commits)
  compat/mingw: brown paper bag fix for 50a6c8ef
  ewah: convert to REALLOC_ARRAY, etc
  convert ewah/bitmap code to use xmalloc
  diff_populate_gitlink: use a strbuf
  transport_anonymize_url: use xstrfmt
  git-compat-util: drop mempcpy compat code
  sequencer: simplify memory allocation of get_message
  test-path-utils: fix normalize_path_copy output buffer size
  fetch-pack: simplify add_sought_entry
  fast-import: simplify allocation in start_packfile
  write_untracked_extension: use FLEX_ALLOC helper
  prepare_{git,shell}_cmd: use argv_array
  use st_add and st_mult for allocation size computation
  convert trivial cases to FLEX_ARRAY macros
  use xmallocz to avoid size arithmetic
  convert trivial cases to ALLOC_ARRAY
  convert manual allocations to argv_array
  argv-array: add detach function
  add helpers for allocating flex-array structs
  harden REALLOC_ARRAY and xcalloc against size_t overflow
  ...

The memory ownership rule of fill_textconv() API, which was a bit
tricky, has been documented a bit better.

* jk/more-comments-on-textconv:
  diff: clarify textconv interface

"git merge-tree" used to mishandle "both sides added" conflict with
its own "create a fake ancestor file that has the common parts of
what both sides have added and do a 3-way merge" logic; this has
been updated to use the usual "3-way merge with an empty blob as
the fake common ancestor file" approach used in the rest of the
system.

* jk/no-diff-emit-common:
  xdiff: drop XDL_EMIT_COMMON
  merge-tree: drop generate_common strategy
  merge-one-file: use empty blob for add/add base

The "v(iew)" subcommand of the interactive "git am -i" command was
broken in 2.6.0 timeframe when the command was rewritten in C.

* jc/am-i-v-fix:
  am -i: fix "v"iew
  pager: factor out a helper to prepare a child process to run the pager
  pager: lose a separate argv[]

"git rev-parse --git-common-dir" used in the worktree feature
misbehaved when run from a subdirectory.

* nd/git-common-dir-fix:
  rev-parse: take prefix into account in --git-common-dir

"git show 'HEAD:Foo[BAR]Baz'" did not interpret the argument as a
rev, i.e. the object named by the the pathname with wildcard
characters in a tree object.

* nd/dwim-wildcards-as-pathspecs:
  get_sha1: don't die() on bogus search strings
  check_filename: tighten dwim-wildcard ambiguity
  checkout: reorder check_filename conditional