There are many scattered functions that look into the contents of
buffers to do various text manipulations (such as escaping or
unescaping data, calculating text stats, guessing if content is
binary, etc). This groups all those functions together into a
new file and converts the code to use that.
This has two enhancements to existing functionality. The old
text stats function is significantly rewritten and the BOM
detection code was extended (although largely we can't deal with
anything other than a UTF8 BOM).
* `git_buf_rfind` (with tests and tests for `git_buf_rfind_next`)
* `git_buf_puts_escaped` and `git_buf_puts_escaped_regex` (with tests)
to copy strings into a buffer while injecting an escape sequence
(e.g. '\') in front of particular characters.
The goal of this work is to rewrite git_status_file to use the
same underlying code as git_status_foreach.
This is done in 3 phases:
1. Extend iterators to allow ranged iteration with start and
end prefixes for the range of file names to be covered.
2. Improve diff so that when there is a pathspec and there is
a common non-wildcard prefix of the pathspec, it will use
ranged iterators to minimize excess iteration.
3. Rewrite git_status_file to call git_status_foreach_ext
with a pathspec that covers just the one file being checked.
Since ranged iterators underlie the status & diff implementation,
this is actually fairly efficient. The workdir iterator does
end up loading the contents of all the directories down to the
single file, which should ideally be avoided, but it is pretty
good.
This updates to the latest clar which includes the helpers
`cl_assert_equal_s` and `cl_assert_equal_i`. Convert the code
over to use those and remove the old libgit2-only helpers.
This makes so much sense that I can't believe it hasn't been done
before. Kill the old `git_fbuffer` and read files straight into
`git_buf` objects.
Also: In order to fully support 4GB files in 32-bit systems, the
`git_buf` implementation has been changed from using `ssize_t` for
storage and storing negative values on allocation failure, to using
`size_t` and changing the buffer pointer to a magical pointer on
allocation failure.
Hopefully this won't break anything.
