Some unit-tests use trace output to verify internal state, and unstable
output such as timestamps and line numbers are not useful there.

Disable additional trace output if GIT_TRACE_BARE is set.
Signed-off-by: NKarsten Blees <blees@dcon.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

To be able to add a common prefix or suffix to all trace output (e.g.
a timestamp or file:line of the caller), factor out common setup and
cleanup tasks of the trace* functions.

When adding a common prefix, it makes sense that the output of each trace
call starts on a new line. Add '\n' in case the caller forgot.

Note that this explicitly limits trace output to line-by-line, it is no
longer possible to trace-print just part of a line. Until now, this was
just an implicit assumption (trace-printing part of a line worked, but
messed up the trace file if multiple threads or processes were involved).

Thread-safety / inter-process-safety is also the reason why we need to do
the prefixing and suffixing in memory rather than issuing multiple write()
calls. Write_or_whine_pipe() / xwrite() is atomic unless the size exceeds
MAX_IO_SIZE (8MB, see wrapper.c). In case of trace_strbuf, this costs an
additional string copy (which should be irrelevant for performance in light
of actual file IO).

While we're at it, rename trace_strbuf's 'buf' argument, which suggests
that the function is modifying the buffer. Trace_strbuf() currently is the
only trace API that can print arbitrary binary data (without barfing on
'%' or stopping at '\0'), so 'data' seems more appropriate.
Signed-off-by: NKarsten Blees <blees@dcon.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This changes GIT_TRACE_PACK_ACCESS functionality as follows:
 * supports the same options as GIT_TRACE (e.g. printing to stderr)
 * no longer supports relative paths
 * appends to the trace file rather than overwriting
Signed-off-by: NKarsten Blees <blees@dcon.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Separate GIT_TRACE description into what it prints and how to configure
where trace output is printed to. Change other GIT_TRACE_* descriptions to
refer to GIT_TRACE.

Add descriptions for GIT_TRACE_SETUP and GIT_TRACE_SHALLOW.
Signed-off-by: NKarsten Blees <blees@dcon.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The trace API currently rechecks the environment variable and reopens the
trace file on every API call. This has the ugly side effect that errors
(e.g. file cannot be opened, or the user specified a relative path) are
also reported on every call. Performance can be improved by about factor
three by remembering the environment state and keeping the file open.

Replace the 'const char *key' parameter in the API with a pointer to a
'struct trace_key' that bundles the environment variable name with
additional, trace-internal state. Change the call sites of these APIs to
use a static 'struct trace_key' instead of a string constant.

In trace.c::get_trace_fd(), save and reuse the file descriptor in 'struct
trace_key'.

Add a 'trace_disable()' API, so that packet_trace() can cleanly disable
tracing when it encounters packed data (instead of using unsetenv()).
Signed-off-by: NKarsten Blees <blees@dcon.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

trace_printf_key() is the only non-static function that duplicates the
printf format attribute in the .c file, remove it for consistency.
Signed-off-by: NKarsten Blees <blees@dcon.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The format parameter to trace_printf functions is sometimes abbreviated
'fmt'. Rename to 'format' everywhere (consistent with POSIX' printf
specification).
Signed-off-by: NKarsten Blees <blees@dcon.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Also include direct dependencies (strbuf.h and git-compat-util.h for
__attribute__) so that trace.h can be used independently of cache.h, e.g.
in test programs.
Signed-off-by: NKarsten Blees <blees@dcon.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

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

Allow specifying only certain individual test pieces to be run
using a range notation (e.g. "t1234-test.sh --run='1-4 6 8 9-'").

* ib/test-selectively-run:
  t0000-*.sh: fix the GIT_SKIP_TESTS sub-tests
  test-lib: '--run' to run only specific tests
  test-lib: tests skipped by GIT_SKIP_TESTS say so
  test-lib: document short options in t/README

* ta/string-list-init:
  string-list: spell all values out that are given to a string_list initializer

* jm/dedup-test-config:
  t/t7810-grep.sh: remove duplicate test_config()

* dt/refs-check-refname-component-optim:
  refs.c: optimize check_refname_component()

* sk/test-cmp-bin:
  t5000, t5003: do not use test_cmp to compare binary files

* sh/enable-preloadindex:
  environment.c: enable core.preloadindex by default

* rs/read-ref-at:
  refs.c: change read_ref_at to use the reflog iterators

* jk/error-resolve-conflict-advice:
  error_resolve_conflict: drop quotations around operation
  error_resolve_conflict: rewrap advice message

Avoid unnecessary copy of previous contents when extending the
hashtable used in pack-objects.

* rs/pack-objects-no-unnecessary-realloc:
  pack-objects: use free()+xcalloc() instead of xrealloc()+memset()

* lt/log-auto-decorate:
  git log: support "auto" decorations

* jm/doc-wording-tweaks:
  Documentation: wording fixes in the user manual and glossary

* jm/format-patch-mail-sig:
  format-patch: add "--signature-file=<file>" option
  format-patch: make newline after signature conditional

Propagate the error messages from the webserver better to the
client coming over the HTTP transport.

* jk/http-errors:
  http: default text charset to iso-8859-1
  remote-curl: reencode http error messages
  strbuf: add strbuf_reencode helper
  http: optionally extract charset parameter from content-type
  http: extract type/subtype portion of content-type
  t5550: test display of remote http error messages
  t/lib-httpd: use write_script to copy CGI scripts
  test-lib: preserve GIT_CURL_VERBOSE from the environment

mailmap.file configuration names a pathname, hence should honor
~/path and ~user/path as its value.

* ow/config-mailmap-pathname:
  config: respect '~' and '~user' in mailmap.file

Allow remote-helper/fast-import based transport to rename the refs
while transferring the history.

* fc/remote-helper-refmap:
  transport-helper: remove unnecessary strbuf resets
  transport-helper: add support to delete branches
  fast-export: add support to delete refs
  fast-import: add support to delete refs
  transport-helper: add support to push symbolic refs
  transport-helper: add support for old:new refspec
  fast-export: add new --refspec option
  fast-export: improve argument parsing

"git gc --auto" was recently changed to run in the background to
give control back early to the end-user sitting in front of the
terminal, but it forgot that housekeeping involving reflogs should
be done without other processes competing for accesses to the refs.

* nd/daemonize-gc:
  gc --auto: do not lock refs in the background

* jm/t9138-style-fix:
  t9138-git-svn-authors-prog.sh fixups

* jm/instaweb-apache-24:
  git-instaweb: add support for Apache 2.4

"git remote rm" and "git remote prune" can involve removing many
refs at once, which is not a very efficient thing to do when very
many refs exist in the packed-refs file.

* jl/remote-rm-prune:
  remote prune: optimize "dangling symref" check/warning
  remote: repack packed-refs once when deleting multiple refs
  remote rm: delete remote configuration as the last

The completion code did not know about quite a few options that are
common between "git merge" and "git pull", and a couple of options
unique to "git merge".

* jk/complete-merge-pull:
  completion: add missing options for git-merge
  completion: add a note that merge options are shared

Like calloc(3), xcalloc() takes nmemb and then size.

* bg/xcalloc-nmemb-then-size:
  transport-helper.c: rearrange xcalloc arguments
  remote.c: rearrange xcalloc arguments
  reflog-walk.c: rearrange xcalloc arguments
  pack-revindex.c: rearrange xcalloc arguments
  notes.c: rearrange xcalloc arguments
  imap-send.c: rearrange xcalloc arguments
  http-push.c: rearrange xcalloc arguments
  diff.c: rearrange xcalloc arguments
  config.c: rearrange xcalloc arguments
  commit.c: rearrange xcalloc arguments
  builtin/remote.c: rearrange xcalloc arguments
  builtin/ls-remote.c: rearrange xcalloc arguments

submodule.*.ignore and diff.ignoresubmodules are used to ignore all
submodule changes in "diff" output, but it can be confusing to
apply these configuration values to status and commit.

This is a backward-incompatible change, but should be so in a good
way (aka bugfix).

* jl/status-added-submodule-is-never-ignored:
  commit -m: commit staged submodules regardless of ignore config
  status/commit: show staged submodules regardless of ignore config

Compatibility enhancement for Solaris.

* cb/byte-order:
  compat/bswap.h: fix endianness detection
  compat/bswap.h: restore preference __BIG_ENDIAN over BIG_ENDIAN
  compat/bswap.h: detect endianness on more platforms that don't use BYTE_ORDER

* jk/strbuf-tolower:
  strbuf: add strbuf_tolower function

* jk/daemon-tolower:
  daemon/config: factor out duplicate xstrdup_tolower

* as/pretty-truncate:
  pretty.c: format string with truncate respects logOutputEncoding
  t4205, t6006: add tests that fail with i18n.logOutputEncoding set
  t4205 (log-pretty-format): use `tformat` rather than `format`
  t4041, t4205, t6006, t7102: don't hardcode tested encoding value
  t4205 (log-pretty-formats): don't hardcode SHA-1 in expected outputs

* jk/diff-follow-must-take-one-pathspec:
  move "--follow needs one pathspec" rule to diff_setup_done

* sk/windows-unc-path:
  Windows: allow using UNC path for git repository

* rr/rebase-autostash-fix:
  rebase -i: test "Nothing to do" case with autostash
  rebase -i: handle "Nothing to do" case with autostash

* jk/report-fail-to-read-objects-better:
  open_sha1_file: report "most interesting" errno

* jk/diff-files-assume-unchanged:
  run_diff_files: do not look at uninitialized stat data