Using a `git_oid *` in filter options was a mistake; it is a deviation
from our typical pattern, and callers in some languages that GC may need
very special treatment in order to pass both an options structure and a
pointer outside of it.
The API `git_filter_list_apply_to_data` shares data between its out and
in parameters to avoid unnecessarily copying it when there are no
filters to apply. However, it does so in a manner that is potentially
confusing, leaving both `git_buf`s populated with data. This is risky
for end-users who have to know how to deal with this. Instead, we
remove this optimization - users who want to avoid unnecessary copies
can use the longstanding streaming API or check the filter status before
invoking the filters.
`git_filter_list_stream_data` takes user input in a `git_buf`.
`git_buf` should only be used when libgit2 itself needs to allocate data
and returned to a user that they can free when they wish. Replace it
with `git_filter_list_stream_buffer` that takes a data buffer and
length.
When `GIT_FILTER_ATTRIBUTES_FROM_HEAD` is specified, configure the
filter to read filter attributes from `gitattributes` files that are
checked in to the repository at the HEAD revision. This passes the flag
`GIT_ATTR_CHECK_INCLUDE_HEAD` to the attribute reading functions.
Add structures and preliminary functions to take a buffer, file or
blob and write the contents in chunks through an arbitrary number
of chained filters, finally writing into a user-provided function
accept the contents.
This makes them show up in the reference, even if the text itself isn't
the most descriptive.
These have been found with
grep -Przon '\n\ntypedef struct.*?\{' -- include
grep -Przon '\n\ntypedef enum.*?\{' -- include
Diff and status do not want core.safecrlf to actually raise an
error regardless of the setting, so this extends the filter API
with an additional options flags parameter and adds a flag so that
filters can be applied with GIT_FILTER_OPT_ALLOW_UNSAFE, indicating
that unsafe filter application should be downgraded from a failure
to a warning.
This makes the git_buf struct that was used internally into an
externally available structure and eliminates the git_buffer.
As part of that, some of the special cases that arose with the
externally used git_buffer were blended into the git_buf, such as
being careful about git_buf objects that may have a NULL ptr and
allowing for bufs with a valid ptr and size but zero asize as a
way of referring to externally owned data.
This adds the ident filter (that knows how to replace $Id$) and
tweaks the filter APIs and code so that git_filter_source objects
actually have the updated OID of the object being filtered when
it is a known value.
Extend the git2/sys/filter API with functions to look up a filter
and add it manually to a filter list. This requires some trickery
because the regular attribute lookups and checks are bypassed when
this happens, but in the right hands, it will allow a user to have
granular control over applying filters.
This moves the git_filter_list into the public API so that users
can create, apply, and dispose of filter lists. This allows more
granular application of filters to user data outside of libgit2
internals.
This also converts all the internal usage of filters to the public
APIs along with a few small tweaks to make it easier to use the
public git_buffer stuff alongside the internal git_buf.
This creates include/sys/filter.h with a basic definition of a
git_filter and then converts the internal code to use it. There
are related internal objects (git_filter_list) that we will want
to publish at some point, but this is a first step.
This begins the process of exposing git_filter objects to the
public API. This includes:
* new public type and API for `git_buffer` through which an
allocated buffer can be passed to the user
* new API `git_blob_filtered_content`
* make the git_filter type and GIT_FILTER_TO_... constants public
