diff options
| -rw-r--r-- | builtin/pull.c | 247 |
1 files changed, 245 insertions, 2 deletions
diff --git a/builtin/pull.c b/builtin/pull.c index 98caffe..33a7b98 100644 --- a/builtin/pull.c +++ b/builtin/pull.c @@ -15,6 +15,53 @@ #include "dir.h" #include "refs.h" +enum rebase_type { + REBASE_INVALID = -1, + REBASE_FALSE = 0, + REBASE_TRUE, + REBASE_PRESERVE +}; + +/** + * Parses the value of --rebase. If value is a false value, returns + * REBASE_FALSE. If value is a true value, returns REBASE_TRUE. If value is + * "preserve", returns REBASE_PRESERVE. If value is a invalid value, dies with + * a fatal error if fatal is true, otherwise returns REBASE_INVALID. + */ +static enum rebase_type parse_config_rebase(const char *key, const char *value, + int fatal) +{ + int v = git_config_maybe_bool("pull.rebase", value); + + if (!v) + return REBASE_FALSE; + else if (v > 0) + return REBASE_TRUE; + else if (!strcmp(value, "preserve")) + return REBASE_PRESERVE; + + if (fatal) + die(_("Invalid value for %s: %s"), key, value); + else + error(_("Invalid value for %s: %s"), key, value); + + return REBASE_INVALID; +} + +/** + * Callback for --rebase, which parses arg with parse_config_rebase(). + */ +static int parse_opt_rebase(const struct option *opt, const char *arg, int unset) +{ + enum rebase_type *value = opt->value; + + if (arg) + *value = parse_config_rebase("--rebase", arg, 0); + else + *value = unset ? REBASE_FALSE : REBASE_TRUE; + return *value == REBASE_INVALID ? -1 : 0; +} + static const char * const pull_usage[] = { N_("git pull [options] [<repository> [<refspec>...]]"), NULL @@ -24,7 +71,8 @@ static const char * const pull_usage[] = { static int opt_verbosity; static char *opt_progress; -/* Options passed to git-merge */ +/* Options passed to git-merge or git-rebase */ +static enum rebase_type opt_rebase; static char *opt_diffstat; static char *opt_log; static char *opt_squash; @@ -58,8 +106,12 @@ static struct option pull_options[] = { N_("force progress reporting"), PARSE_OPT_NOARG), - /* Options passed to git-merge */ + /* Options passed to git-merge or git-rebase */ OPT_GROUP(N_("Options related to merging")), + { OPTION_CALLBACK, 'r', "rebase", &opt_rebase, + N_("false|true|preserve"), + N_("incorporate changes by rebasing rather than merging"), + PARSE_OPT_OPTARG, parse_opt_rebase }, OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL, N_("do not show a diffstat at the end of the merge"), PARSE_OPT_NOARG | PARSE_OPT_NONEG), @@ -449,11 +501,194 @@ static int run_merge(void) return ret; } +/** + * Returns remote's upstream branch for the current branch. If remote is NULL, + * the current branch's configured default remote is used. Returns NULL if + * `remote` does not name a valid remote, HEAD does not point to a branch, + * remote is not the branch's configured remote or the branch does not have any + * configured upstream branch. + */ +static const char *get_upstream_branch(const char *remote) +{ + struct remote *rm; + struct branch *curr_branch; + const char *curr_branch_remote; + + rm = remote_get(remote); + if (!rm) + return NULL; + + curr_branch = branch_get("HEAD"); + if (!curr_branch) + return NULL; + + curr_branch_remote = remote_for_branch(curr_branch, NULL); + assert(curr_branch_remote); + + if (strcmp(curr_branch_remote, rm->name)) + return NULL; + + return branch_get_upstream(curr_branch, NULL); +} + +/** + * Derives the remote tracking branch from the remote and refspec. + * + * FIXME: The current implementation assumes the default mapping of + * refs/heads/<branch_name> to refs/remotes/<remote_name>/<branch_name>. + */ +static const char *get_tracking_branch(const char *remote, const char *refspec) +{ + struct refspec *spec; + const char *spec_src; + const char *merge_branch; + + spec = parse_fetch_refspec(1, &refspec); + spec_src = spec->src; + if (!*spec_src || !strcmp(spec_src, "HEAD")) + spec_src = "HEAD"; + else if (skip_prefix(spec_src, "heads/", &spec_src)) + ; + else if (skip_prefix(spec_src, "refs/heads/", &spec_src)) + ; + else if (starts_with(spec_src, "refs/") || + starts_with(spec_src, "tags/") || + starts_with(spec_src, "remotes/")) + spec_src = ""; + + if (*spec_src) { + if (!strcmp(remote, ".")) + merge_branch = mkpath("refs/heads/%s", spec_src); + else + merge_branch = mkpath("refs/remotes/%s/%s", remote, spec_src); + } else + merge_branch = NULL; + + free_refspec(1, spec); + return merge_branch; +} + +/** + * Given the repo and refspecs, sets fork_point to the point at which the + * current branch forked from its remote tracking branch. Returns 0 on success, + * -1 on failure. + */ +static int get_rebase_fork_point(unsigned char *fork_point, const char *repo, + const char *refspec) +{ + int ret; + struct branch *curr_branch; + const char *remote_branch; + struct child_process cp = CHILD_PROCESS_INIT; + struct strbuf sb = STRBUF_INIT; + + curr_branch = branch_get("HEAD"); + if (!curr_branch) + return -1; + + if (refspec) + remote_branch = get_tracking_branch(repo, refspec); + else + remote_branch = get_upstream_branch(repo); + + if (!remote_branch) + return -1; + + argv_array_pushl(&cp.args, "merge-base", "--fork-point", + remote_branch, curr_branch->name, NULL); + cp.no_stdin = 1; + cp.no_stderr = 1; + cp.git_cmd = 1; + + ret = capture_command(&cp, &sb, GIT_SHA1_HEXSZ); + if (ret) + goto cleanup; + + ret = get_sha1_hex(sb.buf, fork_point); + if (ret) + goto cleanup; + +cleanup: + strbuf_release(&sb); + return ret ? -1 : 0; +} + +/** + * Sets merge_base to the octopus merge base of curr_head, merge_head and + * fork_point. Returns 0 if a merge base is found, 1 otherwise. + */ +static int get_octopus_merge_base(unsigned char *merge_base, + const unsigned char *curr_head, + const unsigned char *merge_head, + const unsigned char *fork_point) +{ + struct commit_list *revs = NULL, *result; + + commit_list_insert(lookup_commit_reference(curr_head), &revs); + commit_list_insert(lookup_commit_reference(merge_head), &revs); + if (!is_null_sha1(fork_point)) + commit_list_insert(lookup_commit_reference(fork_point), &revs); + + result = reduce_heads(get_octopus_merge_bases(revs)); + free_commit_list(revs); + if (!result) + return 1; + + hashcpy(merge_base, result->item->object.sha1); + return 0; +} + +/** + * Given the current HEAD SHA1, the merge head returned from git-fetch and the + * fork point calculated by get_rebase_fork_point(), runs git-rebase with the + * appropriate arguments and returns its exit status. + */ +static int run_rebase(const unsigned char *curr_head, + const unsigned char *merge_head, + const unsigned char *fork_point) +{ + int ret; + unsigned char oct_merge_base[GIT_SHA1_RAWSZ]; + struct argv_array args = ARGV_ARRAY_INIT; + + if (!get_octopus_merge_base(oct_merge_base, curr_head, merge_head, fork_point)) + if (!is_null_sha1(fork_point) && !hashcmp(oct_merge_base, fork_point)) + fork_point = NULL; + + argv_array_push(&args, "rebase"); + + /* Shared options */ + argv_push_verbosity(&args); + + /* Options passed to git-rebase */ + if (opt_rebase == REBASE_PRESERVE) + argv_array_push(&args, "--preserve-merges"); + if (opt_diffstat) + argv_array_push(&args, opt_diffstat); + argv_array_pushv(&args, opt_strategies.argv); + argv_array_pushv(&args, opt_strategy_opts.argv); + if (opt_gpg_sign) + argv_array_push(&args, opt_gpg_sign); + + argv_array_push(&args, "--onto"); + argv_array_push(&args, sha1_to_hex(merge_head)); + + if (fork_point && !is_null_sha1(fork_point)) + argv_array_push(&args, sha1_to_hex(fork_point)); + else + argv_array_push(&args, sha1_to_hex(merge_head)); + + ret = run_command_v_opt(args.argv, RUN_GIT_CMD); + argv_array_clear(&args); + return ret; +} + int cmd_pull(int argc, const char **argv, const char *prefix) { const char *repo, **refspecs; struct sha1_array merge_heads = SHA1_ARRAY_INIT; unsigned char orig_head[GIT_SHA1_RAWSZ], curr_head[GIT_SHA1_RAWSZ]; + unsigned char rebase_fork_point[GIT_SHA1_RAWSZ]; if (!getenv("_GIT_USE_BUILTIN_PULL")) { const char *path = mkpath("%s/git-pull", git_exec_path()); @@ -483,6 +718,10 @@ int cmd_pull(int argc, const char **argv, const char *prefix) if (get_sha1("HEAD", orig_head)) hashclr(orig_head); + if (opt_rebase) + if (get_rebase_fork_point(rebase_fork_point, repo, *refspecs)) + hashclr(rebase_fork_point); + if (run_fetch(repo, refspecs)) return 1; @@ -524,6 +763,10 @@ int cmd_pull(int argc, const char **argv, const char *prefix) if (merge_heads.nr > 1) die(_("Cannot merge multiple branches into empty head.")); return pull_into_void(*merge_heads.sha1, curr_head); + } else if (opt_rebase) { + if (merge_heads.nr > 1) + die(_("Cannot rebase onto multiple branches.")); + return run_rebase(curr_head, *merge_heads.sha1, rebase_fork_point); } else return run_merge(); } |