/* * Builtin "git pull" * * Based on git-pull.sh by Junio C Hamano * * Fetch one or more remote refs and merge it/them into the current HEAD. */ #define USE_THE_INDEX_COMPATIBILITY_MACROS #include "cache.h" #include "config.h" #include "builtin.h" #include "parse-options.h" #include "exec-cmd.h" #include "run-command.h" #include "oid-array.h" #include "remote.h" #include "dir.h" #include "rebase.h" #include "refs.h" #include "refspec.h" #include "revision.h" #include "submodule.h" #include "submodule-config.h" #include "tempfile.h" #include "lockfile.h" #include "wt-status.h" #include "commit-reach.h" #include "sequencer.h" #include "packfile.h" /** * 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 * "merges", returns REBASE_MERGES. 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) { enum rebase_type v = rebase_parse_value(value); if (v != REBASE_INVALID) return v; 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 }; /* Shared options */ static int opt_verbosity; static char *opt_progress; static int recurse_submodules = RECURSE_SUBMODULES_DEFAULT; /* Options passed to git-merge or git-rebase */ static enum rebase_type opt_rebase = -1; static char *opt_diffstat; static char *opt_log; static char *opt_signoff; static char *opt_squash; static char *opt_commit; static char *opt_edit; static char *cleanup_arg; static char *opt_ff; static char *opt_verify_signatures; static char *opt_verify; static int opt_autostash = -1; static int config_autostash; static int check_trust_level = 1; static struct strvec opt_strategies = STRVEC_INIT; static struct strvec opt_strategy_opts = STRVEC_INIT; static char *opt_gpg_sign; static int opt_allow_unrelated_histories; /* Options passed to git-fetch */ static char *opt_all; static char *opt_append; static char *opt_upload_pack; static int opt_force; static char *opt_tags; static char *opt_prune; static char *max_children; static int opt_dry_run; static char *opt_keep; static char *opt_depth; static char *opt_unshallow; static char *opt_update_shallow; static char *opt_refmap; static char *opt_ipv4; static char *opt_ipv6; static int opt_show_forced_updates = -1; static char *set_upstream; static struct strvec opt_fetch = STRVEC_INIT; static struct option pull_options[] = { /* Shared options */ OPT__VERBOSITY(&opt_verbosity), OPT_PASSTHRU(0, "progress", &opt_progress, NULL, N_("force progress reporting"), PARSE_OPT_NOARG), OPT_CALLBACK_F(0, "recurse-submodules", &recurse_submodules, N_("on-demand"), N_("control for recursive fetching of submodules"), PARSE_OPT_OPTARG, option_fetch_parse_recurse_submodules), /* Options passed to git-merge or git-rebase */ OPT_GROUP(N_("Options related to merging")), OPT_CALLBACK_F('r', "rebase", &opt_rebase, "(false|true|merges|interactive)", 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), OPT_PASSTHRU(0, "stat", &opt_diffstat, NULL, N_("show a diffstat at the end of the merge"), PARSE_OPT_NOARG), OPT_PASSTHRU(0, "summary", &opt_diffstat, NULL, N_("(synonym to --stat)"), PARSE_OPT_NOARG | PARSE_OPT_HIDDEN), OPT_PASSTHRU(0, "log", &opt_log, N_("n"), N_("add (at most <n>) entries from shortlog to merge commit message"), PARSE_OPT_OPTARG), OPT_PASSTHRU(0, "signoff", &opt_signoff, NULL, N_("add a Signed-off-by trailer"), PARSE_OPT_OPTARG), OPT_PASSTHRU(0, "squash", &opt_squash, NULL, N_("create a single commit instead of doing a merge"), PARSE_OPT_NOARG), OPT_PASSTHRU(0, "commit", &opt_commit, NULL, N_("perform a commit if the merge succeeds (default)"), PARSE_OPT_NOARG), OPT_PASSTHRU(0, "edit", &opt_edit, NULL, N_("edit message before committing"), PARSE_OPT_NOARG), OPT_CLEANUP(&cleanup_arg), OPT_PASSTHRU(0, "ff", &opt_ff, NULL, N_("allow fast-forward"), PARSE_OPT_NOARG), OPT_PASSTHRU(0, "ff-only", &opt_ff, NULL, N_("abort if fast-forward is not possible"), PARSE_OPT_NOARG | PARSE_OPT_NONEG), OPT_PASSTHRU(0, "verify", &opt_verify, NULL, N_("control use of pre-merge-commit and commit-msg hooks"), PARSE_OPT_NOARG), OPT_PASSTHRU(0, "verify-signatures", &opt_verify_signatures, NULL, N_("verify that the named commit has a valid GPG signature"), PARSE_OPT_NOARG), OPT_BOOL(0, "autostash", &opt_autostash, N_("automatically stash/stash pop before and after")), OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"), N_("merge strategy to use"), 0), OPT_PASSTHRU_ARGV('X', "strategy-option", &opt_strategy_opts, N_("option=value"), N_("option for selected merge strategy"), 0), OPT_PASSTHRU('S', "gpg-sign", &opt_gpg_sign, N_("key-id"), N_("GPG sign commit"), PARSE_OPT_OPTARG), OPT_SET_INT(0, "allow-unrelated-histories", &opt_allow_unrelated_histories, N_("allow merging unrelated histories"), 1), /* Options passed to git-fetch */ OPT_GROUP(N_("Options related to fetching")), OPT_PASSTHRU(0, "all", &opt_all, NULL, N_("fetch from all remotes"), PARSE_OPT_NOARG), OPT_PASSTHRU('a', "append", &opt_append, NULL, N_("append to .git/FETCH_HEAD instead of overwriting"), PARSE_OPT_NOARG), OPT_PASSTHRU(0, "upload-pack", &opt_upload_pack, N_("path"), N_("path to upload pack on remote end"), 0), OPT__FORCE(&opt_force, N_("force overwrite of local branch"), 0), OPT_PASSTHRU('t', "tags", &opt_tags, NULL, N_("fetch all tags and associated objects"), PARSE_OPT_NOARG), OPT_PASSTHRU('p', "prune", &opt_prune, NULL, N_("prune remote-tracking branches no longer on remote"), PARSE_OPT_NOARG), OPT_PASSTHRU('j', "jobs", &max_children, N_("n"), N_("number of submodules pulled in parallel"), PARSE_OPT_OPTARG), OPT_BOOL(0, "dry-run", &opt_dry_run, N_("dry run")), OPT_PASSTHRU('k', "keep", &opt_keep, NULL, N_("keep downloaded pack"), PARSE_OPT_NOARG), OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"), N_("deepen history of shallow clone"), 0), OPT_PASSTHRU_ARGV(0, "shallow-since", &opt_fetch, N_("time"), N_("deepen history of shallow repository based on time"), 0), OPT_PASSTHRU_ARGV(0, "shallow-exclude", &opt_fetch, N_("revision"), N_("deepen history of shallow clone, excluding rev"), 0), OPT_PASSTHRU_ARGV(0, "deepen", &opt_fetch, N_("n"), N_("deepen history of shallow clone"), 0), OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL, N_("convert to a complete repository"), PARSE_OPT_NONEG | PARSE_OPT_NOARG), OPT_PASSTHRU(0, "update-shallow", &opt_update_shallow, NULL, N_("accept refs that update .git/shallow"), PARSE_OPT_NOARG), OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"), N_("specify fetch refmap"), PARSE_OPT_NONEG), OPT_PASSTHRU_ARGV('o', "server-option", &opt_fetch, N_("server-specific"), N_("option to transmit"), 0), OPT_PASSTHRU('4', "ipv4", &opt_ipv4, NULL, N_("use IPv4 addresses only"), PARSE_OPT_NOARG), OPT_PASSTHRU('6', "ipv6", &opt_ipv6, NULL, N_("use IPv6 addresses only"), PARSE_OPT_NOARG), OPT_PASSTHRU_ARGV(0, "negotiation-tip", &opt_fetch, N_("revision"), N_("report that we have only objects reachable from this object"), 0), OPT_BOOL(0, "show-forced-updates", &opt_show_forced_updates, N_("check for forced-updates on all updated branches")), OPT_PASSTHRU(0, "set-upstream", &set_upstream, NULL, N_("set upstream for git pull/fetch"), PARSE_OPT_NOARG), OPT_END() }; /** * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level. */ static void argv_push_verbosity(struct strvec *arr) { int verbosity; for (verbosity = opt_verbosity; verbosity > 0; verbosity--) strvec_push(arr, "-v"); for (verbosity = opt_verbosity; verbosity < 0; verbosity++) strvec_push(arr, "-q"); } /** * Pushes "-f" switches into arr to match the opt_force level. */ static void argv_push_force(struct strvec *arr) { int force = opt_force; while (force-- > 0) strvec_push(arr, "-f"); } /** * Sets the GIT_REFLOG_ACTION environment variable to the concatenation of argv */ static void set_reflog_message(int argc, const char **argv) { int i; struct strbuf msg = STRBUF_INIT; for (i = 0; i < argc; i++) { if (i) strbuf_addch(&msg, ' '); strbuf_addstr(&msg, argv[i]); } setenv("GIT_REFLOG_ACTION", msg.buf, 0); strbuf_release(&msg); } /** * If pull.ff is unset, returns NULL. If pull.ff is "true", returns "--ff". If * pull.ff is "false", returns "--no-ff". If pull.ff is "only", returns * "--ff-only". Otherwise, if pull.ff is set to an invalid value, die with an * error. */ static const char *config_get_ff(void) { const char *value; if (git_config_get_value("pull.ff", &value)) return NULL; switch (git_parse_maybe_bool(value)) { case 0: return "--no-ff"; case 1: return "--ff"; } if (!strcmp(value, "only")) return "--ff-only"; die(_("Invalid value for pull.ff: %s"), value); } /** * Returns the default configured value for --rebase. It first looks for the * value of "branch.$curr_branch.rebase", where $curr_branch is the current * branch, and if HEAD is detached or the configuration key does not exist, * looks for the value of "pull.rebase". If both configuration keys do not * exist, returns REBASE_FALSE. */ static enum rebase_type config_get_rebase(int *rebase_unspecified) { struct branch *curr_branch = branch_get("HEAD"); const char *value; if (curr_branch) { char *key = xstrfmt("branch.%s.rebase", curr_branch->name); if (!git_config_get_value(key, &value)) { enum rebase_type ret = parse_config_rebase(key, value, 1); free(key); return ret; } free(key); } if (!git_config_get_value("pull.rebase", &value)) return parse_config_rebase("pull.rebase", value, 1); *rebase_unspecified = 1; return REBASE_FALSE; } /** * Read config variables. */ static int git_pull_config(const char *var, const char *value, void *cb) { int status; if (!strcmp(var, "rebase.autostash")) { config_autostash = git_config_bool(var, value); return 0; } else if (!strcmp(var, "submodule.recurse")) { recurse_submodules = git_config_bool(var, value) ? RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF; return 0; } else if (!strcmp(var, "gpg.mintrustlevel")) { check_trust_level = 0; } status = git_gpg_config(var, value, cb); if (status) return status; return git_default_config(var, value, cb); } /** * Appends merge candidates from FETCH_HEAD that are not marked not-for-merge * into merge_heads. */ static void get_merge_heads(struct oid_array *merge_heads) { const char *filename = git_path_fetch_head(the_repository); FILE *fp; struct strbuf sb = STRBUF_INIT; struct object_id oid; fp = xfopen(filename, "r"); while (strbuf_getline_lf(&sb, fp) != EOF) { const char *p; if (parse_oid_hex(sb.buf, &oid, &p)) continue; /* invalid line: does not start with object ID */ if (starts_with(p, "\tnot-for-merge\t")) continue; /* ref is not-for-merge */ oid_array_append(merge_heads, &oid); } fclose(fp); strbuf_release(&sb); } /** * Used by die_no_merge_candidates() as a for_each_remote() callback to * retrieve the name of the remote if the repository only has one remote. */ static int get_only_remote(struct remote *remote, void *cb_data) { const char **remote_name = cb_data; if (*remote_name) return -1; *remote_name = remote->name; return 0; } /** * Dies with the appropriate reason for why there are no merge candidates: * * 1. We fetched from a specific remote, and a refspec was given, but it ended * up not fetching anything. This is usually because the user provided a * wildcard refspec which had no matches on the remote end. * * 2. We fetched from a non-default remote, but didn't specify a branch to * merge. We can't use the configured one because it applies to the default * remote, thus the user must specify the branches to merge. * * 3. We fetched from the branch's or repo's default remote, but: * * a. We are not on a branch, so there will never be a configured branch to * merge with. * * b. We are on a branch, but there is no configured branch to merge with. * * 4. We fetched from the branch's or repo's default remote, but the configured * branch to merge didn't get fetched. (Either it doesn't exist, or wasn't * part of the configured fetch refspec.) */ static void NORETURN die_no_merge_candidates(const char *repo, const char **refspecs) { struct branch *curr_branch = branch_get("HEAD"); const char *remote = curr_branch ? curr_branch->remote_name : NULL; if (*refspecs) { if (opt_rebase) fprintf_ln(stderr, _("There is no candidate for rebasing against among the refs that you just fetched.")); else fprintf_ln(stderr, _("There are no candidates for merging among the refs that you just fetched.")); fprintf_ln(stderr, _("Generally this means that you provided a wildcard refspec which had no\n" "matches on the remote end.")); } else if (repo && curr_branch && (!remote || strcmp(repo, remote))) { fprintf_ln(stderr, _("You asked to pull from the remote '%s', but did not specify\n" "a branch. Because this is not the default configured remote\n" "for your current branch, you must specify a branch on the command line."), repo); } else if (!curr_branch) { fprintf_ln(stderr, _("You are not currently on a branch.")); if (opt_rebase) fprintf_ln(stderr, _("Please specify which branch you want to rebase against.")); else fprintf_ln(stderr, _("Please specify which branch you want to merge with.")); fprintf_ln(stderr, _("See git-pull(1) for details.")); fprintf(stderr, "\n"); fprintf_ln(stderr, " git pull %s %s", _("<remote>"), _("<branch>")); fprintf(stderr, "\n"); } else if (!curr_branch->merge_nr) { const char *remote_name = NULL; if (for_each_remote(get_only_remote, &remote_name) || !remote_name) remote_name = _("<remote>"); fprintf_ln(stderr, _("There is no tracking information for the current branch.")); if (opt_rebase) fprintf_ln(stderr, _("Please specify which branch you want to rebase against.")); else fprintf_ln(stderr, _("Please specify which branch you want to merge with.")); fprintf_ln(stderr, _("See git-pull(1) for details.")); fprintf(stderr, "\n"); fprintf_ln(stderr, " git pull %s %s", _("<remote>"), _("<branch>")); fprintf(stderr, "\n"); fprintf_ln(stderr, _("If you wish to set tracking information for this branch you can do so with:")); fprintf(stderr, "\n"); fprintf_ln(stderr, " git branch --set-upstream-to=%s/%s %s\n", remote_name, _("<branch>"), curr_branch->name); } else fprintf_ln(stderr, _("Your configuration specifies to merge with the ref '%s'\n" "from the remote, but no such ref was fetched."), *curr_branch->merge_name); exit(1); } /** * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo` * as a string and `refspecs` as a null-terminated array of strings. If `repo` * is not provided in argv, it is set to NULL. */ static void parse_repo_refspecs(int argc, const char **argv, const char **repo, const char ***refspecs) { if (argc > 0) { *repo = *argv++; argc--; } else *repo = NULL; *refspecs = argv; } /** * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the * repository and refspecs to fetch, or NULL if they are not provided. */ static int run_fetch(const char *repo, const char **refspecs) { struct strvec args = STRVEC_INIT; int ret; strvec_pushl(&args, "fetch", "--update-head-ok", NULL); /* Shared options */ argv_push_verbosity(&args); if (opt_progress) strvec_push(&args, opt_progress); /* Options passed to git-fetch */ if (opt_all) strvec_push(&args, opt_all); if (opt_append) strvec_push(&args, opt_append); if (opt_upload_pack) strvec_push(&args, opt_upload_pack); argv_push_force(&args); if (opt_tags) strvec_push(&args, opt_tags); if (opt_prune) strvec_push(&args, opt_prune); if (recurse_submodules != RECURSE_SUBMODULES_DEFAULT) switch (recurse_submodules) { case RECURSE_SUBMODULES_ON: strvec_push(&args, "--recurse-submodules=on"); break; case RECURSE_SUBMODULES_OFF: strvec_push(&args, "--recurse-submodules=no"); break; case RECURSE_SUBMODULES_ON_DEMAND: strvec_push(&args, "--recurse-submodules=on-demand"); break; default: BUG("submodule recursion option not understood"); } if (max_children) strvec_push(&args, max_children); if (opt_dry_run) strvec_push(&args, "--dry-run"); if (opt_keep) strvec_push(&args, opt_keep); if (opt_depth) strvec_push(&args, opt_depth); if (opt_unshallow) strvec_push(&args, opt_unshallow); if (opt_update_shallow) strvec_push(&args, opt_update_shallow); if (opt_refmap) strvec_push(&args, opt_refmap); if (opt_ipv4) strvec_push(&args, opt_ipv4); if (opt_ipv6) strvec_push(&args, opt_ipv6); if (opt_show_forced_updates > 0) strvec_push(&args, "--show-forced-updates"); else if (opt_show_forced_updates == 0) strvec_push(&args, "--no-show-forced-updates"); if (set_upstream) strvec_push(&args, set_upstream); strvec_pushv(&args, opt_fetch.v); if (repo) { strvec_push(&args, repo); strvec_pushv(&args, refspecs); } else if (*refspecs) BUG("refspecs without repo?"); ret = run_command_v_opt(args.v, RUN_GIT_CMD | RUN_CLOSE_OBJECT_STORE); strvec_clear(&args); return ret; } /** * "Pulls into void" by branching off merge_head. */ static int pull_into_void(const struct object_id *merge_head, const struct object_id *curr_head) { if (opt_verify_signatures) { struct commit *commit; commit = lookup_commit(the_repository, merge_head); if (!commit) die(_("unable to access commit %s"), oid_to_hex(merge_head)); verify_merge_signature(commit, opt_verbosity, check_trust_level); } /* * Two-way merge: we treat the index as based on an empty tree, * and try to fast-forward to HEAD. This ensures we will not lose * index/worktree changes that the user already made on the unborn * branch. */ if (checkout_fast_forward(the_repository, the_hash_algo->empty_tree, merge_head, 0)) return 1; if (update_ref("initial pull", "HEAD", merge_head, curr_head, 0, UPDATE_REFS_DIE_ON_ERR)) return 1; return 0; } static int rebase_submodules(void) { struct child_process cp = CHILD_PROCESS_INIT; cp.git_cmd = 1; cp.no_stdin = 1; strvec_pushl(&cp.args, "submodule", "update", "--recursive", "--rebase", NULL); argv_push_verbosity(&cp.args); return run_command(&cp); } static int update_submodules(void) { struct child_process cp = CHILD_PROCESS_INIT; cp.git_cmd = 1; cp.no_stdin = 1; strvec_pushl(&cp.args, "submodule", "update", "--recursive", "--checkout", NULL); argv_push_verbosity(&cp.args); return run_command(&cp); } /** * Runs git-merge, returning its exit status. */ static int run_merge(void) { int ret; struct strvec args = STRVEC_INIT; strvec_pushl(&args, "merge", NULL); /* Shared options */ argv_push_verbosity(&args); if (opt_progress) strvec_push(&args, opt_progress); /* Options passed to git-merge */ if (opt_diffstat) strvec_push(&args, opt_diffstat); if (opt_log) strvec_push(&args, opt_log); if (opt_signoff) strvec_push(&args, opt_signoff); if (opt_squash) strvec_push(&args, opt_squash); if (opt_commit) strvec_push(&args, opt_commit); if (opt_edit) strvec_push(&args, opt_edit); if (cleanup_arg) strvec_pushf(&args, "--cleanup=%s", cleanup_arg); if (opt_ff) strvec_push(&args, opt_ff); if (opt_verify) strvec_push(&args, opt_verify); if (opt_verify_signatures) strvec_push(&args, opt_verify_signatures); strvec_pushv(&args, opt_strategies.v); strvec_pushv(&args, opt_strategy_opts.v); if (opt_gpg_sign) strvec_push(&args, opt_gpg_sign); if (opt_autostash == 0) strvec_push(&args, "--no-autostash"); else if (opt_autostash == 1) strvec_push(&args, "--autostash"); if (opt_allow_unrelated_histories > 0) strvec_push(&args, "--allow-unrelated-histories"); strvec_push(&args, "FETCH_HEAD"); ret = run_command_v_opt(args.v, RUN_GIT_CMD); strvec_clear(&args); 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_item spec; const char *spec_src; const char *merge_branch; refspec_item_init_or_die(&spec, refspec, REFSPEC_FETCH); 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; refspec_item_clear(&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(struct object_id *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; strvec_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_MAX_HEXSZ); if (ret) goto cleanup; ret = get_oid_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(struct object_id *merge_base, const struct object_id *curr_head, const struct object_id *merge_head, const struct object_id *fork_point) { struct commit_list *revs = NULL, *result; commit_list_insert(lookup_commit_reference(the_repository, curr_head), &revs); commit_list_insert(lookup_commit_reference(the_repository, merge_head), &revs); if (!is_null_oid(fork_point)) commit_list_insert(lookup_commit_reference(the_repository, fork_point), &revs); result = get_octopus_merge_bases(revs); free_commit_list(revs); reduce_heads_replace(&result); if (!result) return 1; oidcpy(merge_base, &result->item->object.oid); free_commit_list(result); return 0; } /** * Given the current HEAD oid, the merge head returned from git-fetch and the * fork point calculated by get_rebase_fork_point(), compute the <newbase> and * <upstream> arguments to use for the upcoming git-rebase invocation. */ static int get_rebase_newbase_and_upstream(struct object_id *newbase, struct object_id *upstream, const struct object_id *curr_head, const struct object_id *merge_head, const struct object_id *fork_point) { struct object_id oct_merge_base; if (!get_octopus_merge_base(&oct_merge_base, curr_head, merge_head, fork_point)) if (!is_null_oid(fork_point) && oideq(&oct_merge_base, fork_point)) fork_point = NULL; if (fork_point && !is_null_oid(fork_point)) oidcpy(upstream, fork_point); else oidcpy(upstream, merge_head); oidcpy(newbase, merge_head); return 0; } /** * Given the <newbase> and <upstream> calculated by * get_rebase_newbase_and_upstream(), runs git-rebase with the * appropriate arguments and returns its exit status. */ static int run_rebase(const struct object_id *newbase, const struct object_id *upstream) { int ret; struct strvec args = STRVEC_INIT; strvec_push(&args, "rebase"); /* Shared options */ argv_push_verbosity(&args); /* Options passed to git-rebase */ if (opt_rebase == REBASE_MERGES) strvec_push(&args, "--rebase-merges"); else if (opt_rebase == REBASE_INTERACTIVE) strvec_push(&args, "--interactive"); if (opt_diffstat) strvec_push(&args, opt_diffstat); strvec_pushv(&args, opt_strategies.v); strvec_pushv(&args, opt_strategy_opts.v); if (opt_gpg_sign) strvec_push(&args, opt_gpg_sign); if (opt_signoff) strvec_push(&args, opt_signoff); if (opt_autostash == 0) strvec_push(&args, "--no-autostash"); else if (opt_autostash == 1) strvec_push(&args, "--autostash"); if (opt_verify_signatures && !strcmp(opt_verify_signatures, "--verify-signatures")) warning(_("ignoring --verify-signatures for rebase")); strvec_push(&args, "--onto"); strvec_push(&args, oid_to_hex(newbase)); strvec_push(&args, oid_to_hex(upstream)); ret = run_command_v_opt(args.v, RUN_GIT_CMD); strvec_clear(&args); return ret; } static int get_can_ff(struct object_id *orig_head, struct oid_array *merge_heads) { int ret; struct commit_list *list = NULL; struct commit *merge_head, *head; struct object_id *orig_merge_head; if (merge_heads->nr > 1) return 0; orig_merge_head = &merge_heads->oid[0]; head = lookup_commit_reference(the_repository, orig_head); commit_list_insert(head, &list); merge_head = lookup_commit_reference(the_repository, orig_merge_head); ret = repo_is_descendant_of(the_repository, merge_head, list); free_commit_list(list); return ret; } /* * Is orig_head a descendant of _all_ merge_heads? * Unfortunately is_descendant_of() cannot be used as it asks * if orig_head is a descendant of at least one of them. */ static int already_up_to_date(struct object_id *orig_head, struct oid_array *merge_heads) { int i; struct commit *ours; ours = lookup_commit_reference(the_repository, orig_head); for (i = 0; i < merge_heads->nr; i++) { struct commit_list *list = NULL; struct commit *theirs; int ok; theirs = lookup_commit_reference(the_repository, &merge_heads->oid[i]); commit_list_insert(theirs, &list); ok = repo_is_descendant_of(the_repository, ours, list); free_commit_list(list); if (!ok) return 0; } return 1; } static void show_advice_pull_non_ff(void) { advise(_("You have divergent branches and need to specify how to reconcile them.\n" "You can do so by running one of the following commands sometime before\n" "your next pull:\n" "\n" " git config pull.rebase false # merge\n" " git config pull.rebase true # rebase\n" " git config pull.ff only # fast-forward only\n" "\n" "You can replace \"git config\" with \"git config --global\" to set a default\n" "preference for all repositories. You can also pass --rebase, --no-rebase,\n" "or --ff-only on the command line to override the configured default per\n" "invocation.\n")); } int cmd_pull(int argc, const char **argv, const char *prefix) { const char *repo, **refspecs; struct oid_array merge_heads = OID_ARRAY_INIT; struct object_id orig_head, curr_head; struct object_id rebase_fork_point; int rebase_unspecified = 0; int can_ff; int divergent; if (!getenv("GIT_REFLOG_ACTION")) set_reflog_message(argc, argv); git_config(git_pull_config, NULL); prepare_repo_settings(the_repository); the_repository->settings.command_requires_full_index = 0; argc = parse_options(argc, argv, prefix, pull_options, pull_usage, 0); if (cleanup_arg) /* * this only checks the validity of cleanup_arg; we don't need * a valid value for use_editor */ get_cleanup_mode(cleanup_arg, 0); parse_repo_refspecs(argc, argv, &repo, &refspecs); if (!opt_ff) { opt_ff = xstrdup_or_null(config_get_ff()); /* * A subtle point: opt_ff was set on the line above via * reading from config. opt_rebase, in contrast, is set * before this point via command line options. The setting * of opt_rebase via reading from config (using * config_get_rebase()) does not happen until later. We * are relying on the next if-condition happening before * the config_get_rebase() call so that an explicit * "--rebase" can override a config setting of * pull.ff=only. */ if (opt_rebase >= 0 && opt_ff && !strcmp(opt_ff, "--ff-only")) opt_ff = "--ff"; } if (opt_rebase < 0) opt_rebase = config_get_rebase(&rebase_unspecified); if (read_cache_unmerged()) die_resolve_conflict("pull"); if (file_exists(git_path_merge_head(the_repository))) die_conclude_merge(); if (get_oid("HEAD", &orig_head)) oidclr(&orig_head); if (opt_rebase) { if (opt_autostash == -1) opt_autostash = config_autostash; if (is_null_oid(&orig_head) && !is_cache_unborn()) die(_("Updating an unborn branch with changes added to the index.")); if (!opt_autostash) require_clean_work_tree(the_repository, N_("pull with rebase"), _("please commit or stash them."), 1, 0); if (get_rebase_fork_point(&rebase_fork_point, repo, *refspecs)) oidclr(&rebase_fork_point); } if (run_fetch(repo, refspecs)) return 1; if (opt_dry_run) return 0; if (get_oid("HEAD", &curr_head)) oidclr(&curr_head); if (!is_null_oid(&orig_head) && !is_null_oid(&curr_head) && !oideq(&orig_head, &curr_head)) { /* * The fetch involved updating the current branch. * * The working tree and the index file are still based on * orig_head commit, but we are merging into curr_head. * Update the working tree to match curr_head. */ warning(_("fetch updated the current branch head.\n" "fast-forwarding your working tree from\n" "commit %s."), oid_to_hex(&orig_head)); if (checkout_fast_forward(the_repository, &orig_head, &curr_head, 0)) die(_("Cannot fast-forward your working tree.\n" "After making sure that you saved anything precious from\n" "$ git diff %s\n" "output, run\n" "$ git reset --hard\n" "to recover."), oid_to_hex(&orig_head)); } get_merge_heads(&merge_heads); if (!merge_heads.nr) die_no_merge_candidates(repo, refspecs); if (is_null_oid(&orig_head)) { if (merge_heads.nr > 1) die(_("Cannot merge multiple branches into empty head.")); return pull_into_void(merge_heads.oid, &curr_head); } if (merge_heads.nr > 1) { if (opt_rebase) die(_("Cannot rebase onto multiple branches.")); if (opt_ff && !strcmp(opt_ff, "--ff-only")) die(_("Cannot fast-forward to multiple branches.")); } can_ff = get_can_ff(&orig_head, &merge_heads); divergent = !can_ff && !already_up_to_date(&orig_head, &merge_heads); /* ff-only takes precedence over rebase */ if (opt_ff && !strcmp(opt_ff, "--ff-only")) { if (divergent) die_ff_impossible(); opt_rebase = REBASE_FALSE; } /* If no action specified and we can't fast forward, then warn. */ if (!opt_ff && rebase_unspecified && divergent) { show_advice_pull_non_ff(); die(_("Need to specify how to reconcile divergent branches.")); } if (opt_rebase) { int ret = 0; struct object_id newbase; struct object_id upstream; get_rebase_newbase_and_upstream(&newbase, &upstream, &curr_head, merge_heads.oid, &rebase_fork_point); if ((recurse_submodules == RECURSE_SUBMODULES_ON || recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) && submodule_touches_in_range(the_repository, &upstream, &curr_head)) die(_("cannot rebase with locally recorded submodule modifications")); if (can_ff) { /* we can fast-forward this without invoking rebase */ opt_ff = "--ff-only"; ret = run_merge(); } else { ret = run_rebase(&newbase, &upstream); } if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON || recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)) ret = rebase_submodules(); return ret; } else { int ret = run_merge(); if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON || recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)) ret = update_submodules(); return ret; } }