Documentation: update "howto maintain git"

The flow described in the document is still correct, but over time I
have automated various parts of the workflow with tools and their
use was not explained at all.

Update it and outline the use of two key scripts from the 'todo'
branch, "Reintegrate" and "cook".

Signed-off-by: Junio C Hamano <gitster@pobox.com>
howto/maintain: mark titles for asciidoc
t5404: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5505: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5516: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5517: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5519: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t5531: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t7406: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t9400: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t9401: do not assume the "matching" push is the default

Signed-off-by: Junio C Hamano <gitster@pobox.com>
push: switch default from "matching" to "simple"

We promised to change the behaviour of lazy "git push [there]" that
does not say what to push on the command line from "matching" to
"simple" in Git 2.0.

This finally flips that bit.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
dir.c: use a single struct exclude_list per source of excludes

Previously each exclude_list could potentially contain patterns
from multiple sources.  For example dir->exclude_list[EXC_FILE]
would typically contain patterns from .git/info/exclude and
core.excludesfile, and dir->exclude_list[EXC_DIRS] could contain
patterns from multiple per-directory .gitignore files during
directory traversal (i.e. when dir->exclude_stack was more than
one item deep).

We split these composite exclude_lists up into three groups of
exclude_lists (EXC_CMDL / EXC_DIRS / EXC_FILE as before), so that each
exclude_list now contains patterns from a single source.  This will
allow us to cleanly track the origin of each pattern simply by adding
a src field to struct exclude_list, rather than to struct exclude,
which would make memory management of the source string tricky in the
EXC_DIRS case where its contents are dynamically generated.

Similarly, by moving the filebuf member from struct exclude_stack to
struct exclude_list, it allows us to track and subsequently free
memory buffers allocated during the parsing of all exclude files,
rather than only tracking buffers allocated for files in the EXC_DIRS
group.

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
dir.c: keep track of where patterns came from

For exclude patterns read in from files, the filename is stored in the
exclude list, and the originating line number is stored in the
individual exclude (counting starting at 1).

For exclude patterns provided on the command line, a string describing
the source of the patterns is stored in the exclude list, and the
sequence number assigned to each exclude pattern is negative, with
counting starting at -1.  So for example the 2nd pattern provided via
--exclude would be numbered -2.  This allows any future consumers of
that data to easily distinguish between exclude patterns from files
vs. from the CLI.

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
dir.c: provide clear_directory() for reclaiming dir_struct memory

By the end of a directory traversal, a dir_struct instance will
typically contains pointers to various data structures on the heap.
clear_directory() provides a convenient way to reclaim that memory.

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
dir.c: improve docs for match_pathspec() and match_pathspec_depth()

Fix a grammatical issue in the description of these functions, and
make it more obvious how and why seen[] can be reused across multiple
invocations.

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add.c: remove unused argument from validate_pathspec()

The 'argc' argument passed to validate_pathspec() was never used.

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add.c: move pathspec matchers into new pathspec.c for reuse

Extract the following functions from builtin/add.c to pathspec.c, in
preparation for reuse by a new git check-ignore command:

  - fill_pathspec_matches()
  - find_used_pathspec()

The functions being extracted are not changed in any way, except
removal of the 'static' qualifier.

Also add comments documenting these newly public functions,
including clarifications that they operate on the index.

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
pathspec.c: rename newly public functions for clarity

Perform the following function renames to make it explicit that these
pathspec handling functions are for matching against the index, rather
than against a tree or the working directory.

- fill_pathspec_matches() -> add_pathspec_matches_against_index()
- find_used_pathspec() -> find_pathspecs_matching_against_index()

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add.c: extract check_path_for_gitlink() from treat_gitlinks() for reuse

Extract the body of the for loop in treat_gitlinks() into a separate
check_path_for_gitlink() function so that it can be reused elsewhere.
This paves the way for a new check-ignore sub-command.

Also document treat_gitlinks().

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>