Upgrade xdiff to version used in core git 2.4.5 (0df0541).
Corrects an issue where an LF is added at EOF while applying
an unrelated change (ba31180), cleans up some unused code (be89977 and
e5b0662), and provides an improved callback to avoid leaking internal
(to xdiff) structures (467d348).
This also adds some additional functionality that we do not yet take
advantage of, namely the ability to ignore changes whose lines are
all blank (36617af).
Versions prior to 0.9.8f did not have this function, rhel/centos5 are still on a
heavily backported version of 0.9.8e and theoretically supported until March 2017
Without this ifdef, I get the following link failure:
```
CMakeFiles/libgit2_clar.dir/src/openssl_stream.c.o: In function `openssl_connect':
openssl_stream.c:(.text+0x45a): undefined reference to `SSL_set_tlsext_host_name'
collect2: error: ld returned 1 exit status
make[6]: *** [libgit2_clar] Error 1
```
Introduce `git__getenv` which is a UTF-8 aware `getenv` everywhere.
Make `cl_getenv` use this to keep consistent memory handling around
return values (free everywhere, as opposed to only some platforms).
The regex we use to look at the gitmodules file does not correctly
delimit the name of submodule which we want to look up and puts '.*'
straight after the name, maching on any submodule which has the seeked
submodule as a prefix of its name.
Add the missing '\.' in the regex so we want a full stop to exist both
before and after the submodule name.
Allow custom filters with wildcard attributes, so that clients
can support some random `filter=foo` in a .gitattributes and look
up the corresponding smudge/clean commands in the configuration file.
Function was added in commit 2c982daa2e on October 5, 2011,
and removed in commit 41fb1ca0ec on October 29, 2012.
Given the length of time it's gone unused, it's safe to remove now.
This reverts commit 969d4b703c.
This was a fluke from Coverity. The length to all the APIs in the
library is supposed to be passed in as nibbles, not bytes. Passing it as
bytes would prevent us from parsing uneven-sized SHA1 strings.
Also, the rest of the library was still using nibbles (including
revparse and the odb_prefix APIs), so this change was seriously breaking
things in unexpected ways. ^^
When diffing the index with the workdir and GIT_DIFF_UPDATE_INDEX has been passed,
the previous implementation was always writing the index to disk even if it wasn't
modified.
