The diff hunk context string that is returned to xdiff need not
be NUL terminated because the xdiff code just copies the number of
bytes that you report directly into the output. There was an off
by one in the diff driver code when the header context was longer
than the output buffer size, the output buffer length included
the NUL byte which was copied into the hunk header.
Fixes#1710
This changes the size data to uint32_t, fixes the array growth
logic to use a simple 1.5x multiplier, and uses a generic inline
function for growing the array to make the git_array_alloc API
feel more natural (i.e. it returns a pointer to the new item).
This implements the loading of regular expression pattern lists
for diff drivers that search for function context in that way.
This also changes the way that diff drivers update options and
interface with xdiff APIs to make them a little more flexible.
This is a significant reorganization of the diff code to break it
into a set of more clearly distinct files and to document the new
organization. Hopefully this will make the diff code easier to
understand and to extend.
This adds a new `git_diff_driver` object that looks of diff driver
information from the attributes and the config so that things like
function content in diff headers can be provided. The full driver
spec is not implemented in the commit - this is focused on the
reorganization of the code and putting the driver hooks in place.
This also removes a few #includes from src/repository.h that were
overbroad, but as a result required extra #includes in a variety
of places since including src/repository.h no longer results in
pulling in the whole world.
