Jeff King
a28d2bfe19
Our import of xdiff has two identical buffer structures: mmfile_t and
mmbuffer_t. In upstream xdiff these were actually different, but the
import in 3443546f6e (Use a *real* built-in diff generator, 2006-03-24)
simplified mmfile_t to a simple buffer.
In xdiff we usually use mmfile_t for input and mmbuffer_t for output,
but they are really both just a ptr/len pair. I don't think that having
different types is buying us anything in terms of type safety or
semantics, and having two makes it awkward to use the same helpers for
both. In particular, an external merge driver's output is read from a
file, but we can't easily use read_mmfile(), since we want the result in
an mmbuffer_t.
Let's use mmfile_t for both cases and drop mmbuffer_t. The latter is
probably a more descriptive name, but we have many more uses of
mmfile_t (and helpers like read_mmfile). So let's consolidate using that
name; we can always change it to something more sensible later.
There should be no behavior change here; this is just consolidating the
types.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
117 lines
3.4 KiB
C
117 lines
3.4 KiB
C
/*
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* Low level 3-way in-core file merge.
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*/
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#ifndef LL_MERGE_H
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#define LL_MERGE_H
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#include "xdiff/xdiff.h"
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/**
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*
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* Calling sequence:
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* ----------------
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*
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* - Prepare a `struct ll_merge_options` to record options.
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* If you have no special requests, skip this and pass `NULL`
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* as the `opts` parameter to use the default options.
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*
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* - Allocate an mmfile_t variable for the result.
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*
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* - Allocate and fill variables with the file's original content
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* and two modified versions (using `read_mmfile`, for example).
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*
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* - Call `ll_merge()`.
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*
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* - Read the merged content from `result_buf.ptr` and `result_buf.size`.
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*
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* - Release buffers when finished. A simple
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* `free(ancestor.ptr); free(ours.ptr); free(theirs.ptr);
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* free(result_buf.ptr);` will do.
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*
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* If the modifications do not merge cleanly, `ll_merge` will return a
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* nonzero value and `result_buf` will generally include a description of
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* the conflict bracketed by markers such as the traditional `<<<<<<<`
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* and `>>>>>>>`.
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*
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* The `ancestor_label`, `our_label`, and `their_label` parameters are
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* used to label the different sides of a conflict if the merge driver
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* supports this.
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*/
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struct index_state;
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/**
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* This describes the set of options the calling program wants to affect
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* the operation of a low-level (single file) merge.
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*/
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struct ll_merge_options {
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/**
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* Behave as though this were part of a merge between common ancestors in
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* a recursive merge (merges of binary files may need to be handled
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* differently in such cases, for example). If a helper program is
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* specified by the `[merge "<driver>"] recursive` configuration, it will
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* be used.
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*/
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unsigned virtual_ancestor : 1;
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/**
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* Resolve local conflicts automatically in favor of one side or the other
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* (as in 'git merge-file' `--ours`/`--theirs`/`--union`). Can be `0`,
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* `XDL_MERGE_FAVOR_OURS`, `XDL_MERGE_FAVOR_THEIRS`,
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* or `XDL_MERGE_FAVOR_UNION`.
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*/
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unsigned variant : 2;
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/**
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* Resmudge and clean the "base", "theirs" and "ours" files before merging.
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* Use this when the merge is likely to have overlapped with a change in
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* smudge/clean or end-of-line normalization rules.
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*/
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unsigned renormalize : 1;
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/**
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* Increase the length of conflict markers so that nested conflicts
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* can be differentiated.
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*/
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unsigned extra_marker_size;
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/* Override the global conflict style. */
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int conflict_style;
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/* Extra xpparam_t flags as defined in xdiff/xdiff.h. */
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long xdl_opts;
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};
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#define LL_MERGE_OPTIONS_INIT { .conflict_style = -1 }
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enum ll_merge_result {
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LL_MERGE_ERROR = -1,
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LL_MERGE_OK = 0,
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LL_MERGE_CONFLICT,
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LL_MERGE_BINARY_CONFLICT,
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};
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/**
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* Perform a three-way single-file merge in core. This is a thin wrapper
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* around `xdl_merge` that takes the path and any merge backend specified in
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* `.gitattributes` or `.git/info/attributes` into account.
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* Returns 0 for a clean merge.
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*/
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enum ll_merge_result ll_merge(mmfile_t *result_buf,
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const char *path,
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mmfile_t *ancestor, const char *ancestor_label,
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mmfile_t *ours, const char *our_label,
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mmfile_t *theirs, const char *their_label,
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struct index_state *istate,
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const struct ll_merge_options *opts);
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int ll_merge_marker_size(struct index_state *istate, const char *path);
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int is_conflict_marker_line(const char *line, unsigned long len, int marker_size);
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int has_conflict_markers(struct index_state *istate, const char *path);
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void reset_merge_attributes(void);
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#endif
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