root/merge.c

DEFINITIONS

1. merge_argument
2. try_merge_command
3. checkout_fast_forward

#include "cache.h"
#include "lockfile.h"
#include "commit.h"
#include "run-command.h"
#include "resolve-undo.h"
#include "tree-walk.h"
#include "unpack-trees.h"
#include "dir.h"

static const char *merge_argument(struct commit *commit)
{
        if (commit)
                return sha1_to_hex(commit->object.sha1);
        else
                return EMPTY_TREE_SHA1_HEX;
}

int try_merge_command(const char *strategy, size_t xopts_nr,
                      const char **xopts, struct commit_list *common,
                      const char *head_arg, struct commit_list *remotes)
{
        struct argv_array args = ARGV_ARRAY_INIT;
        int i, ret;
        struct commit_list *j;

        argv_array_pushf(&args, "merge-%s", strategy);
        for (i = 0; i < xopts_nr; i++)
                argv_array_pushf(&args, "--%s", xopts[i]);
        for (j = common; j; j = j->next)
                argv_array_push(&args, merge_argument(j->item));
        argv_array_push(&args, "--");
        argv_array_push(&args, head_arg);
        for (j = remotes; j; j = j->next)
                argv_array_push(&args, merge_argument(j->item));

        ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
        argv_array_clear(&args);

        discard_cache();
        if (read_cache() < 0)
                die(_("failed to read the cache"));
        resolve_undo_clear();

        return ret;
}

int checkout_fast_forward(const unsigned char *head,
                          const unsigned char *remote,
                          int overwrite_ignore)
{
        struct tree *trees[MAX_UNPACK_TREES];
        struct unpack_trees_options opts;
        struct tree_desc t[MAX_UNPACK_TREES];
        int i, nr_trees = 0;
        struct dir_struct dir;
        struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));

        refresh_cache(REFRESH_QUIET);

        hold_locked_index(lock_file, 1);

        memset(&trees, 0, sizeof(trees));
        memset(&opts, 0, sizeof(opts));
        memset(&t, 0, sizeof(t));
        if (overwrite_ignore) {
                memset(&dir, 0, sizeof(dir));
                dir.flags |= DIR_SHOW_IGNORED;
                setup_standard_excludes(&dir);
                opts.dir = &dir;
        }

        opts.head_idx = 1;
        opts.src_index = &the_index;
        opts.dst_index = &the_index;
        opts.update = 1;
        opts.verbose_update = 1;
        opts.merge = 1;
        opts.fn = twoway_merge;
        setup_unpack_trees_porcelain(&opts, "merge");

        trees[nr_trees] = parse_tree_indirect(head);
        if (!trees[nr_trees++])
                return -1;
        trees[nr_trees] = parse_tree_indirect(remote);
        if (!trees[nr_trees++])
                return -1;
        for (i = 0; i < nr_trees; i++) {
                parse_tree(trees[i]);
                init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
        }
        if (unpack_trees(nr_trees, t, &opts))
                return -1;
        if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
                die(_("unable to write new index file"));
        return 0;
}