Code cleanup.

* rs/copy-array:
  use COPY_ARRAY
  add COPY_ARRAY

Add a semantic patch for converting certain calls of memcpy(3) to
COPY_ARRAY() and apply that transformation to the code base.  The result
is
 shorter and safer code.  For now only consider calls where source and
destination have the same type, or in other words: easy cases.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

When "git merge-recursive" works on history with many criss-cross
merges in "verbose" mode, the names the command assigns to the
virtual merge bases could have overwritten each other by unintended
reuse of the same piece of memory.

* rs/pull-signed-tag:
  commit: use FLEX_ARRAY in struct merge_remote_desc
  merge-recursive: fix verbose output for multiple base trees
  commit: factor out set_merge_remote_desc()
  commit: use xstrdup() in get_merge_parent()

Convert the name member of struct merge_remote_desc to a FLEX_ARRAY and
use FLEX_ALLOC_STR to build the struct.  This halves the number of
memory allocations, saves the storage for a pointer and avoids an
indirection when reading the name.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Export a helper function for allocating, populating and attaching a
merge_remote_desc to a commit.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Handle allocation errors for the name member just like we already do
for the struct merge_remote_desc itself.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

"git commit --amend --allow-empty-message -S" for a commit without
any message body could have misidentified where the header of the
commit object ends.

* js/sign-empty-commit-fix:
  commit -S: avoid invalid pointer with empty message

A helper function that takes the contents of a commit object and
finds its subject line did not ignore leading blank lines, as is
commonly done by other codepaths.  Make it ignore leading blank
lines to match.

* js/find-commit-subject-ignore-leading-blanks:
  reset --hard: skip blank lines when reporting the commit subject
  sequencer: use skip_blank_lines() to find the commit subject
  commit -C: skip blank lines at the beginning of the message
  commit.c: make find_commit_subject() more robust
  pretty: make the skip_blank_lines() function public

Code clean-up to avoid using a variable string that compilers may
feel untrustable as printf-style format given to write_file()
helper function.

* jk/printf-format:
  commit.c: remove print_commit_list()
  avoid using sha1_to_hex output as printf format
  walker: let walker_say take arbitrary formats

"git commit --amend --allow-empty-message -S" for a commit without
any message body could have misidentified where the header of the
commit object ends.

* js/sign-empty-commit-fix:
  commit -S: avoid invalid pointer with empty message