git/merge-recursive.h

#ifndef MERGE_RECURSIVE_H
#define MERGE_RECURSIVE_H

#include "strbuf.h"

struct commit;
struct commit_list;
struct object_id;
struct repository;
struct tree;

struct merge_options_internal;
struct merge_options { … };

/* for use by porcelain commands */
void init_ui_merge_options(struct merge_options *opt, struct repository *repo);
/* for use by plumbing commands */
void init_basic_merge_options(struct merge_options *opt, struct repository *repo);

void copy_merge_options(struct merge_options *dst, struct merge_options *src);
void clear_merge_options(struct merge_options *opt);

/* parse the option in s and update the relevant field of opt */
int parse_merge_opt(struct merge_options *opt, const char *s);

/*
 * RETURN VALUES: All the merge_* functions below return a value as follows:
 *   > 0     Merge was clean
 *   = 0     Merge had conflicts
 *   < 0     Merge hit an unexpected and unrecoverable problem (e.g. disk
 *             full) and aborted merge part-way through.
 */

/*
 * rename-detecting three-way merge, no recursion.
 *
 * Outputs:
 *   - See RETURN VALUES above
 *   - opt->repo->index has the new index
 *   - new index NOT written to disk
 *   - The working tree is updated with results of the merge
 */
int merge_trees(struct merge_options *opt,
		struct tree *head,
		struct tree *merge,
		struct tree *merge_base);

/*
 * merge_recursive is like merge_trees() but with recursive ancestor
 * consolidation.
 *
 * NOTE: empirically, about a decade ago it was determined that with more
 *       than two merge bases, optimal behavior was found when the
 *       merge_bases were passed in the order of oldest commit to newest
 *       commit.  Also, merge_bases will be consumed (emptied) so make a
 *       copy if you need it.
 *
 * Outputs:
 *   - See RETURN VALUES above
 *   - *result is treated as scratch space for temporary recursive merges
 *   - opt->repo->index has the new index
 *   - new index NOT written to disk
 *   - The working tree is updated with results of the merge
 */
int merge_recursive(struct merge_options *opt,
		    struct commit *h1,
		    struct commit *h2,
		    const struct commit_list *merge_bases,
		    struct commit **result);

/*
 * merge_recursive_generic can operate on trees instead of commits, by
 * wrapping the trees into virtual commits, and calling merge_recursive().
 * It also writes out the in-memory index to disk if the merge is successful.
 *
 * Outputs:
 *   - See RETURN VALUES above
 *   - *result is treated as scratch space for temporary recursive merges
 *   - opt->repo->index has the new index
 *   - new index also written to $GIT_INDEX_FILE on disk
 *   - The working tree is updated with results of the merge
 */
int merge_recursive_generic(struct merge_options *opt,
			    const struct object_id *head,
			    const struct object_id *merge,
			    int num_merge_bases,
			    const struct object_id *merge_bases,
			    struct commit **result);

#endif