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>

Add COPY_ARRAY, a safe and convenient helper for copying arrays,
complementing ALLOC_ARRAY and REALLOC_ARRAY.  Users just specify source,
destination and the number of elements; the size of an element is
inferred automatically.

It checks if the multiplication of size and element count overflows.
The inferred size is passed first to st_mult, which allows the division
there to be done at compilation time.

As a basic type safety check it makes sure the sizes of source and
destination elements are the same.  That's evaluated at compilation time
as well.

COPY_ARRAY is safe to use with NULL as source pointer iff 0 elements are
to be copied.  That convention is used in some cases for initializing
arrays.  Raw memcpy(3) does not support it -- compilers are allowed to
assume that only valid pointers are passed to it and can optimize away
NULL checks after such a call.

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

Conversion from unsigned char sha1[20] to struct object_id
continues.

* bc/cocci:
  diff: convert prep_temp_blob() to struct object_id
  merge-recursive: convert merge_recursive_generic() to object_id
  merge-recursive: convert leaf functions to use struct object_id
  merge-recursive: convert struct merge_file_info to object_id
  merge-recursive: convert struct stage_data to use object_id
  diff: rename struct diff_filespec's sha1_valid member
  diff: convert struct diff_filespec to struct object_id
  coccinelle: apply object_id Coccinelle transformations
  coccinelle: convert hashcpy() with null_sha1 to hashclr()
  contrib/coccinelle: add basic Coccinelle transforms
  hex: add oid_to_hex_r()

The commands in the "log/diff" family have had an FILE* pointer in the
data structure they pass around for a long time, but some codepaths
used to always write to the standard output.  As a preparatory step
to make "git format-patch" available to the internal callers, these
codepaths have been updated to consistently write into that FILE*
instead.

* js/log-to-diffopt-file:
  mingw: fix the shortlog --output=<file> test
  diff: do not color output when --color=auto and --output=<file> is given
  t4211: ensure that log respects --output=<file>
  shortlog: respect the --output=<file> setting
  format-patch: use stdout directly
  format-patch: avoid freopen()
  format-patch: explicitly switch off color when writing to files
  shortlog: support outputting to streams other than stdout
  graph: respect the diffopt.file setting
  line-log: respect diffopt's configured output file stream
  log-tree: respect diffopt's configured output file stream
  log: prepare log/log-tree to reuse the diffopt.close_file attribute

Fix recently introduced codepaths that are involved in parallel
submodule operations, which gave up on reading too early, and
could have wasted CPU while attempting to write under a corner
case condition.

* sb/submodule-parallel-fetch:
  hoist out handle_nonblock function for xread and xwrite
  xwrite: poll on non-blocking FDs
  xread: retry after poll on EAGAIN/EWOULDBLOCK

Code simplification.

* lf/recv-sideband-cleanup:
  sideband.c: small optimization of strbuf usage
  sideband.c: refactor recv_sideband()

"git blame -M" missed a single line that was moved within the file.

* dk/blame-move-no-reason-for-1-line-context:
  blame: require 0 context lines while finding moved lines with -M

A new configuration variable core.sshCommand has been added to
specify what value for GIT_SSH_COMMAND to use per repository.

* nd/connect-ssh-command-config:
  connect: read $GIT_SSH_COMMAND from config file

As we are not yet moving everything to size_t but still using ulong
internally when talking about the size of object, platforms with
32-bit long will not be able to produce tar archive with 4GB+ file,
and cannot grok 077777777777UL as a constant.  Disable the extended
header feature and do not test it on them.

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

* maint:
  Git 2.9.2
  t0006: skip "far in the future" test when unsigned long is not long enough