Add data structures and basic functions for commit trailers

We will use a doubly linked list to store all information
about trailers and their configuration.

This way we can easily remove or add trailers to or from
trailer lists while traversing the lists in either direction.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: process trailers from file and arguments

This patch implements the logic that process trailers
from file and arguments.

At the beginning trailers from file are in their own
infile_tok doubly linked list, and trailers from
arguments are in their own arg_tok doubly linked list.

The lists are traversed and when an arg_tok should be
"applied", it is removed from its list and inserted
into the infile_tok list.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: read and process config information

This patch implements reading the configuration
to get trailer information, and then processing
it and storing it in a doubly linked list.

The config information is stored in the list
whose first item is pointed to by:

static struct trailer_item *first_conf_item;

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: process command line trailer arguments

This patch parses the trailer command line arguments
and put the result into an arg_tok doubly linked
list.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: parse trailers from input file

This patch reads trailers from an input file, parses
them and puts the result into a doubly linked list.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: put all the processing together and print

This patch adds the process_trailers() function that
calls all the previously added processing functions
and then prints the results on the standard output.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: add interpret-trailers command

This patch adds the "git interpret-trailers" command.
This command uses the previously added process_trailers()
function in trailer.c.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: add tests for "git interpret-trailers"

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: if no input file is passed, read from stdin

It is simpler and more natural if the "git interpret-trailers"
is made a filter as its output already goes to sdtout.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: execute command from 'trailer.<name>.command'

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: add tests for trailer command

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: set author and committer env variables

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
trailer: add tests for commands using env variables

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation: add documentation for 'git interpret-trailers'

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
pack-protocol.txt: clarify 'obj-id' in the last ACK after 'done'

It's introduced in 1bd8c8f (git-upload-pack: Support the multi_ack
protocol - 2005-10-28) but probably better documented in the commit
message of 78affc4 (Add multi_ack_detailed capability to
fetch-pack/upload-pack - 2009-10-30).

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
protocol-capabilities.txt: refer multi_ack_detailed back to pack-protocol.txt

pack-protocol.txt explains in detail how multi_ack_detailed works and
what's the difference between no multi_ack, multi_ack and
multi_ack_detailed. No need to repeat here.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
protocol-capabilities.txt: document no-done

See 3e63b21 (upload-pack: Implement no-done capability - 2011-03-14)
and 761ecf0 (fetch-pack: Implement no-done capability - 2011-03-14)
for more information.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
fetch-pack: fix deepen shallow over smart http with no-done cap

In smart http, upload-pack adds new shallow lines at the beginning of
each rpc response. Only shallow lines from the first rpc call are
useful. After that they are thrown away. It's designed this way
because upload-pack is stateless and has no idea when its shallow
lines are helpful or not.

So after refs are negotiated with multi_ack_detailed and the server
thinks it learned enough, it sends "ACK obj-id ready", terminates the
rpc call and waits for the final rpc round. The client sends "done".
The server sends another response, which also has shallow lines at
the beginning, and the last "ACK obj-id" line.

When no-done is active, the last round is cut out, the server sends
"ACK obj-id ready" and "ACK obj-id" in the same rpc
response. fetch-pack is updated to recognize this and not send
"done". However it still tries to consume shallow lines, which are
never sent.

Update the code, make sure to skip consuming shallow lines when
no-done is enabled.

Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'kb/fast-hashmap' (early part) into jch

* 'kb/fast-hashmap' (early part):
  name-hash: retire unused index_name_exists()
  hashmap.h: Use 'unsigned int' for hash-codes everywhere
  Drop unnecessary #includes from test-hashmap
  Add test-hashmap to .gitignore
  read-cache.c: fix memory leaks caused by removed cache entries
  builtin/update-index.c: cleanup update_one
  fix 'git update-index --verbose --again' output
  remove old hash.[ch] implementation
  name-hash.c: remove cache entries instead of marking them CE_UNHASHED
  name-hash.c: use new hash map implementation for cache entries
  name-hash.c: remove unreferenced directory entries
  name-hash.c: use new hash map implementation for directories
  diffcore-rename.c: use new hash map implementation
  diffcore-rename.c: simplify finding exact renames
  diffcore-rename.c: move code around to prepare for the next patch
  buitin/describe.c: use new hash map implementation
  add a hashtable implementation that supports O(1) removal
  submodule: don't access the .gitmodules cache entry after removing it
Merge branch 'nv/commit-gpgsign-config' into jch

Introduce commit.gpgsign configuration variable to force every
commit to be GPG signed.  The variable cannot be overriden from the
command line of some of the commands that create commits except for
"git commit" and "git commit-tree", but I am not convinced that it
is a good idea to sprinkle support for --no-gpg-sign everywhere.

* nv/commit-gpgsign-config:
  test the commit.gpgsign config option
  commit-tree: add and document --no-gpg-sign
  Add the commit.gpgsign option to sign all commits