The diff_options structure has an output_prefix callback for returning a
prefix string, but it does so by returning a pointer to a strbuf.
This makes the interface awkward. There's no reason the callback should
need to use a strbuf, and it creates questions about whether the
ownership of the resulting buffer should be transferred to the caller
(it should not be, but a recent attempt to clean up this code led to a
double-free in some cases).
The one advantage we get is that the strbuf contains a ptr/len pair, so
we could in theory have a prefix with embedded NULs. But we can observe
that none of the existing callbacks would ever produce such a NUL (they
are usually just indentation or graph symbols, and even the
"--line-prefix" option takes a NUL-terminated string).
And anyway, only one caller (the one in log_tree_diff_flush) actually
looks at the strbuf length. In every other case we use a helper function
which discards the length and just returns the NUL-terminated string.
So let's just have the callback return a "const char *" pointer. It's up
to the callbacks themselves if they want to use a strbuf under the hood.
And now the caller in log_tree_diff_flush() can just use the helper
function along with everybody else. That lets us even simplify out the
function pointer check, since the helper returns an empty string
(technically this does mean we'll sometimes issue an empty fputs() call,
but I don't think this code path is hot enough to care about that).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an
unusually rich command set that provides both high-level operations
and full access to internals.
Git is an Open Source project covered by the GNU General Public
License version 2 (some parts of it are under different licenses,
compatible with the GPLv2). It was originally written by Linus
Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/
including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-<commandname>.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
Those wishing to help with error message, usage and informational message
string translations (localization l10) should see po/README.md
(a po file is a Portable Object file that holds the translations).
Issues which are security relevant should be disclosed privately to
the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that
list the current status of various development topics to the mailing
list. The discussion following them give a good reference for
project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very
first version. He described the tool as "the stupid content tracker"
and the name as (depending on your mood):
random three-letter combination that is pronounceable, and not
actually used by any common UNIX command. The fact that it is a
mispronunciation of "get" may or may not be relevant.
stupid. contemptible and despicable. simple. Take your pick from the
dictionary of slang.
"global information tracker": you're in a good mood, and it actually
works for you. Angels sing, and a light suddenly fills the room.
"goddamn idiotic truckload of sh*t": when it breaks
