diff options
author | Elijah Newren <newren@gmail.com> | 2023-05-16 09:34:04 +0300 |
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committer | Junio C Hamano <gitster@pobox.com> | 2023-06-21 23:39:54 +0300 |
commit | 6723899932eb5b6436e9bac65ffc9b6e644c7fee (patch) | |
tree | 6621add1d88821ec177f7154dbe4616ee55bb737 /merge-ll.h | |
parent | dd77d587954bd798d0ea6b26f0815ed2d78d47b9 (diff) |
merge-ll: rename from ll-merge
A long term (but rather minor) pet-peeve of mine was the name
ll-merge.[ch]. I thought it made it harder to realize what stuff was
related to merging when I was working on the merge machinery and trying
to improve it.
Further, back in d1cbe1e6d8a ("hash-ll.h: split out of hash.h to remove
dependency on repository.h", 2023-04-22), we have split the portions of
hash.h that do not depend upon repository.h into a "hash-ll.h" (due to
the recommendation to use "ll" for "low-level" in its name[1], but which
I used as a suffix precisely because of my distaste for "ll-merge").
When we discussed adding additional "*-ll.h" files, a request was made
that we use "ll" consistently as either a prefix or a suffix. Since it
is already in use as both a prefix and a suffix, the only way to do so
is to rename some files.
Besides my distaste for the ll-merge.[ch] name, let me also note that
the files
ll-fsmonitor.h, ll-hash.h, ll-merge.h, ll-object-store.h, ll-read-cache.h
would have essentially nothing to do with each other and make no sense
to group. But giving them the common "ll-" prefix would group them. Using
"-ll" as a suffix thus seems just much more logical to me. Rename
ll-merge.[ch] to merge-ll.[ch] to achieve this consistency, and to
ensure we get a more logical grouping of files.
[1] https://lore.kernel.org/git/kl6lsfcu1g8w.fsf@chooglen-macbookpro.roam.corp.google.com/
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'merge-ll.h')
-rw-r--r-- | merge-ll.h | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/merge-ll.h b/merge-ll.h new file mode 100644 index 0000000000..e4a20e81a3 --- /dev/null +++ b/merge-ll.h @@ -0,0 +1,109 @@ +/* + * Low level 3-way in-core file merge. + */ + +#ifndef LL_MERGE_H +#define LL_MERGE_H + +#include "xdiff/xdiff.h" + +/** + * + * Calling sequence: + * ---------------- + * + * - Prepare a `struct ll_merge_options` to record options. + * If you have no special requests, skip this and pass `NULL` + * as the `opts` parameter to use the default options. + * + * - Allocate an mmbuffer_t variable for the result. + * + * - Allocate and fill variables with the file's original content + * and two modified versions (using `read_mmfile`, for example). + * + * - Call `ll_merge()`. + * + * - Read the merged content from `result_buf.ptr` and `result_buf.size`. + * + * - Release buffers when finished. A simple + * `free(ancestor.ptr); free(ours.ptr); free(theirs.ptr); + * free(result_buf.ptr);` will do. + * + * If the modifications do not merge cleanly, `ll_merge` will return a + * nonzero value and `result_buf` will generally include a description of + * the conflict bracketed by markers such as the traditional `<<<<<<<` + * and `>>>>>>>`. + * + * The `ancestor_label`, `our_label`, and `their_label` parameters are + * used to label the different sides of a conflict if the merge driver + * supports this. + */ + + +struct index_state; + +/** + * This describes the set of options the calling program wants to affect + * the operation of a low-level (single file) merge. + */ +struct ll_merge_options { + + /** + * Behave as though this were part of a merge between common ancestors in + * a recursive merge (merges of binary files may need to be handled + * differently in such cases, for example). If a helper program is + * specified by the `[merge "<driver>"] recursive` configuration, it will + * be used. + */ + unsigned virtual_ancestor : 1; + + /** + * Resolve local conflicts automatically in favor of one side or the other + * (as in 'git merge-file' `--ours`/`--theirs`/`--union`). Can be `0`, + * `XDL_MERGE_FAVOR_OURS`, `XDL_MERGE_FAVOR_THEIRS`, + * or `XDL_MERGE_FAVOR_UNION`. + */ + unsigned variant : 2; + + /** + * Resmudge and clean the "base", "theirs" and "ours" files before merging. + * Use this when the merge is likely to have overlapped with a change in + * smudge/clean or end-of-line normalization rules. + */ + unsigned renormalize : 1; + + /** + * Increase the length of conflict markers so that nested conflicts + * can be differentiated. + */ + unsigned extra_marker_size; + + /* Extra xpparam_t flags as defined in xdiff/xdiff.h. */ + long xdl_opts; +}; + +enum ll_merge_result { + LL_MERGE_ERROR = -1, + LL_MERGE_OK = 0, + LL_MERGE_CONFLICT, + LL_MERGE_BINARY_CONFLICT, +}; + +/** + * Perform a three-way single-file merge in core. This is a thin wrapper + * around `xdl_merge` that takes the path and any merge backend specified in + * `.gitattributes` or `.git/info/attributes` into account. + * Returns 0 for a clean merge. + */ +enum ll_merge_result ll_merge(mmbuffer_t *result_buf, + const char *path, + mmfile_t *ancestor, const char *ancestor_label, + mmfile_t *ours, const char *our_label, + mmfile_t *theirs, const char *their_label, + struct index_state *istate, + const struct ll_merge_options *opts); + +int ll_merge_marker_size(struct index_state *istate, const char *path); +void reset_merge_attributes(void); + +#endif |