#include "cache.h" #include "builtin.h" #include "parse-options.h" #include "refs.h" #include "commit.h" #include "tree.h" #include "tree-walk.h" #include "unpack-trees.h" #include "dir.h" #include "run-command.h" #include "merge-recursive.h" #include "branch.h" #include "diff.h" #include "revision.h" #include "remote.h" #include "blob.h" #include "xdiff-interface.h" #include "ll-merge.h" static const char * const checkout_usage[] = { "git checkout [options] <branch>", "git checkout [options] [<branch>] -- <file>...", NULL, }; struct checkout_opts { int quiet; int merge; int force; int writeout_stage; int writeout_error; const char *new_branch; int new_branch_log; enum branch_track track; }; static int post_checkout_hook(struct commit *old, struct commit *new, int changed) { return run_hook(NULL, "post-checkout", sha1_to_hex(old ? old->object.sha1 : null_sha1), sha1_to_hex(new ? new->object.sha1 : null_sha1), changed ? "1" : "0", NULL); /* "new" can be NULL when checking out from the index before a commit exists. */ } static int update_some(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage, void *context) { int len; struct cache_entry *ce; if (S_ISGITLINK(mode)) return 0; if (S_ISDIR(mode)) return READ_TREE_RECURSIVE; len = baselen + strlen(pathname); ce = xcalloc(1, cache_entry_size(len)); hashcpy(ce->sha1, sha1); memcpy(ce->name, base, baselen); memcpy(ce->name + baselen, pathname, len - baselen); ce->ce_flags = create_ce_flags(len, 0); ce->ce_mode = create_ce_mode(mode); add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE); return 0; } static int read_tree_some(struct tree *tree, const char **pathspec) { read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL); /* update the index with the given tree's info * for all args, expanding wildcards, and exit * with any non-zero return code. */ return 0; } static int skip_same_name(struct cache_entry *ce, int pos) { while (++pos < active_nr && !strcmp(active_cache[pos]->name, ce->name)) ; /* skip */ return pos; } static int check_stage(int stage, struct cache_entry *ce, int pos) { while (pos < active_nr && !strcmp(active_cache[pos]->name, ce->name)) { if (ce_stage(active_cache[pos]) == stage) return 0; pos++; } return error("path '%s' does not have %s version", ce->name, (stage == 2) ? "our" : "their"); } static int check_all_stages(struct cache_entry *ce, int pos) { if (ce_stage(ce) != 1 || active_nr <= pos + 2 || strcmp(active_cache[pos+1]->name, ce->name) || ce_stage(active_cache[pos+1]) != 2 || strcmp(active_cache[pos+2]->name, ce->name) || ce_stage(active_cache[pos+2]) != 3) return error("path '%s' does not have all three versions", ce->name); return 0; } static int checkout_stage(int stage, struct cache_entry *ce, int pos, struct checkout *state) { while (pos < active_nr && !strcmp(active_cache[pos]->name, ce->name)) { if (ce_stage(active_cache[pos]) == stage) return checkout_entry(active_cache[pos], state, NULL); pos++; } return error("path '%s' does not have %s version", ce->name, (stage == 2) ? "our" : "their"); } /* NEEDSWORK: share with merge-recursive */ static void fill_mm(const unsigned char *sha1, mmfile_t *mm) { unsigned long size; enum object_type type; if (!hashcmp(sha1, null_sha1)) { mm->ptr = xstrdup(""); mm->size = 0; return; } mm->ptr = read_sha1_file(sha1, &type, &size); if (!mm->ptr || type != OBJ_BLOB) die("unable to read blob object %s", sha1_to_hex(sha1)); mm->size = size; } static int checkout_merged(int pos, struct checkout *state) { struct cache_entry *ce = active_cache[pos]; const char *path = ce->name; mmfile_t ancestor, ours, theirs; int status; unsigned char sha1[20]; mmbuffer_t result_buf; if (ce_stage(ce) != 1 || active_nr <= pos + 2 || strcmp(active_cache[pos+1]->name, path) || ce_stage(active_cache[pos+1]) != 2 || strcmp(active_cache[pos+2]->name, path) || ce_stage(active_cache[pos+2]) != 3) return error("path '%s' does not have all 3 versions", path); fill_mm(active_cache[pos]->sha1, &ancestor); fill_mm(active_cache[pos+1]->sha1, &ours); fill_mm(active_cache[pos+2]->sha1, &theirs); status = ll_merge(&result_buf, path, &ancestor, &ours, "ours", &theirs, "theirs", 1); free(ancestor.ptr); free(ours.ptr); free(theirs.ptr); if (status < 0 || !result_buf.ptr) { free(result_buf.ptr); return error("path '%s': cannot merge", path); } /* * NEEDSWORK: * There is absolutely no reason to write this as a blob object * and create a phoney cache entry just to leak. This hack is * primarily to get to the write_entry() machinery that massages * the contents to work-tree format and writes out which only * allows it for a cache entry. The code in write_entry() needs * to be refactored to allow us to feed a <buffer, size, mode> * instead of a cache entry. Such a refactoring would help * merge_recursive as well (it also writes the merge result to the * object database even when it may contain conflicts). */ if (write_sha1_file(result_buf.ptr, result_buf.size, blob_type, sha1)) die("Unable to add merge result for '%s'", path); ce = make_cache_entry(create_ce_mode(active_cache[pos+1]->ce_mode), sha1, path, 2, 0); if (!ce) die("make_cache_entry failed for path '%s'", path); status = checkout_entry(ce, state, NULL); return status; } static int checkout_paths(struct tree *source_tree, const char **pathspec, struct checkout_opts *opts) { int pos; struct checkout state; static char *ps_matched; unsigned char rev[20]; int flag; struct commit *head; int errs = 0; int stage = opts->writeout_stage; int merge = opts->merge; int newfd; struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file)); newfd = hold_locked_index(lock_file, 1); if (read_cache() < 0) return error("corrupt index file"); if (source_tree) read_tree_some(source_tree, pathspec); for (pos = 0; pathspec[pos]; pos++) ; ps_matched = xcalloc(1, pos); for (pos = 0; pos < active_nr; pos++) { struct cache_entry *ce = active_cache[pos]; match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, ps_matched); } if (report_path_error(ps_matched, pathspec, 0)) return 1; /* Any unmerged paths? */ for (pos = 0; pos < active_nr; pos++) { struct cache_entry *ce = active_cache[pos]; if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) { if (!ce_stage(ce)) continue; if (opts->force) { warning("path '%s' is unmerged", ce->name); } else if (stage) { errs |= check_stage(stage, ce, pos); } else if (opts->merge) { errs |= check_all_stages(ce, pos); } else { errs = 1; error("path '%s' is unmerged", ce->name); } pos = skip_same_name(ce, pos) - 1; } } if (errs) return 1; /* Now we are committed to check them out */ memset(&state, 0, sizeof(state)); state.force = 1; state.refresh_cache = 1; for (pos = 0; pos < active_nr; pos++) { struct cache_entry *ce = active_cache[pos]; if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) { if (!ce_stage(ce)) { errs |= checkout_entry(ce, &state, NULL); continue; } if (stage) errs |= checkout_stage(stage, ce, pos, &state); else if (merge) errs |= checkout_merged(pos, &state); pos = skip_same_name(ce, pos) - 1; } } if (write_cache(newfd, active_cache, active_nr) || commit_locked_index(lock_file)) die("unable to write new index file"); resolve_ref("HEAD", rev, 0, &flag); head = lookup_commit_reference_gently(rev, 1); errs |= post_checkout_hook(head, head, 0); return errs; } static void show_local_changes(struct object *head) { struct rev_info rev; /* I think we want full paths, even if we're in a subdirectory. */ init_revisions(&rev, NULL); rev.abbrev = 0; rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS; if (diff_setup_done(&rev.diffopt) < 0) die("diff_setup_done failed"); add_pending_object(&rev, head, NULL); run_diff_index(&rev, 0); } static void describe_detached_head(char *msg, struct commit *commit) { struct strbuf sb = STRBUF_INIT; parse_commit(commit); pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, 0, NULL, NULL, 0, 0); fprintf(stderr, "%s %s... %s\n", msg, find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf); strbuf_release(&sb); } static int reset_tree(struct tree *tree, struct checkout_opts *o, int worktree) { struct unpack_trees_options opts; struct tree_desc tree_desc; memset(&opts, 0, sizeof(opts)); opts.head_idx = -1; opts.update = worktree; opts.skip_unmerged = !worktree; opts.reset = 1; opts.merge = 1; opts.fn = oneway_merge; opts.verbose_update = !o->quiet; opts.src_index = &the_index; opts.dst_index = &the_index; parse_tree(tree); init_tree_desc(&tree_desc, tree->buffer, tree->size); switch (unpack_trees(1, &tree_desc, &opts)) { case -2: o->writeout_error = 1; /* * We return 0 nevertheless, as the index is all right * and more importantly we have made best efforts to * update paths in the work tree, and we cannot revert * them. */ case 0: return 0; default: return 128; } } struct branch_info { const char *name; /* The short name used */ const char *path; /* The full name of a real branch */ struct commit *commit; /* The named commit */ }; static void setup_branch_path(struct branch_info *branch) { struct strbuf buf = STRBUF_INIT; int ret; if ((ret = interpret_nth_last_branch(branch->name, &buf)) && ret == strlen(branch->name)) { branch->name = xstrdup(buf.buf); strbuf_splice(&buf, 0, 0, "refs/heads/", 11); } else { strbuf_addstr(&buf, "refs/heads/"); strbuf_addstr(&buf, branch->name); } branch->path = strbuf_detach(&buf, NULL); } static int merge_working_tree(struct checkout_opts *opts, struct branch_info *old, struct branch_info *new) { int ret; struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file)); int newfd = hold_locked_index(lock_file, 1); if (read_cache() < 0) return error("corrupt index file"); if (opts->force) { ret = reset_tree(new->commit->tree, opts, 1); if (ret) return ret; } else { struct tree_desc trees[2]; struct tree *tree; struct unpack_trees_options topts; memset(&topts, 0, sizeof(topts)); topts.head_idx = -1; topts.src_index = &the_index; topts.dst_index = &the_index; topts.msgs.not_uptodate_file = "You have local changes to '%s'; cannot switch branches."; refresh_cache(REFRESH_QUIET); if (unmerged_cache()) { error("you need to resolve your current index first"); return 1; } /* 2-way merge to the new branch */ topts.initial_checkout = is_cache_unborn(); topts.update = 1; topts.merge = 1; topts.gently = opts->merge; topts.verbose_update = !opts->quiet; topts.fn = twoway_merge; topts.dir = xcalloc(1, sizeof(*topts.dir)); topts.dir->show_ignored = 1; topts.dir->exclude_per_dir = ".gitignore"; tree = parse_tree_indirect(old->commit->object.sha1); init_tree_desc(&trees[0], tree->buffer, tree->size); tree = parse_tree_indirect(new->commit->object.sha1); init_tree_desc(&trees[1], tree->buffer, tree->size); ret = unpack_trees(2, trees, &topts); if (ret == -1) { /* * Unpack couldn't do a trivial merge; either * give up or do a real merge, depending on * whether the merge flag was used. */ struct tree *result; struct tree *work; struct merge_options o; if (!opts->merge) return 1; parse_commit(old->commit); /* Do more real merge */ /* * We update the index fully, then write the * tree from the index, then merge the new * branch with the current tree, with the old * branch as the base. Then we reset the index * (but not the working tree) to the new * branch, leaving the working tree as the * merged version, but skipping unmerged * entries in the index. */ add_files_to_cache(NULL, NULL, 0); init_merge_options(&o); o.verbosity = 0; work = write_tree_from_memory(&o); ret = reset_tree(new->commit->tree, opts, 1); if (ret) return ret; o.branch1 = new->name; o.branch2 = "local"; merge_trees(&o, new->commit->tree, work, old->commit->tree, &result); ret = reset_tree(new->commit->tree, opts, 0); if (ret) return ret; } } if (write_cache(newfd, active_cache, active_nr) || commit_locked_index(lock_file)) die("unable to write new index file"); if (!opts->force && !opts->quiet) show_local_changes(&new->commit->object); return 0; } static void report_tracking(struct branch_info *new) { struct strbuf sb = STRBUF_INIT; struct branch *branch = branch_get(new->name); if (!format_tracking_info(branch, &sb)) return; fputs(sb.buf, stdout); strbuf_release(&sb); } static void update_refs_for_switch(struct checkout_opts *opts, struct branch_info *old, struct branch_info *new) { struct strbuf msg = STRBUF_INIT; const char *old_desc; if (opts->new_branch) { create_branch(old->name, opts->new_branch, new->name, 0, opts->new_branch_log, opts->track); new->name = opts->new_branch; setup_branch_path(new); } old_desc = old->name; if (!old_desc && old->commit) old_desc = sha1_to_hex(old->commit->object.sha1); strbuf_addf(&msg, "checkout: moving from %s to %s", old_desc ? old_desc : "(invalid)", new->name); if (new->path) { create_symref("HEAD", new->path, msg.buf); if (!opts->quiet) { if (old->path && !strcmp(new->path, old->path)) fprintf(stderr, "Already on \"%s\"\n", new->name); else fprintf(stderr, "Switched to%s branch \"%s\"\n", opts->new_branch ? " a new" : "", new->name); } } else if (strcmp(new->name, "HEAD")) { update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL, REF_NODEREF, DIE_ON_ERR); if (!opts->quiet) { if (old->path) fprintf(stderr, "Note: moving to \"%s\" which isn't a local branch\nIf you want to create a new branch from this checkout, you may do so\n(now or later) by using -b with the checkout command again. Example:\n git checkout -b <new_branch_name>\n", new->name); describe_detached_head("HEAD is now at", new->commit); } } remove_branch_state(); strbuf_release(&msg); if (!opts->quiet && (new->path || !strcmp(new->name, "HEAD"))) report_tracking(new); } static int switch_branches(struct checkout_opts *opts, struct branch_info *new) { int ret = 0; struct branch_info old; unsigned char rev[20]; int flag; memset(&old, 0, sizeof(old)); old.path = resolve_ref("HEAD", rev, 0, &flag); old.commit = lookup_commit_reference_gently(rev, 1); if (!(flag & REF_ISSYMREF)) old.path = NULL; if (old.path && !prefixcmp(old.path, "refs/heads/")) old.name = old.path + strlen("refs/heads/"); if (!new->name) { new->name = "HEAD"; new->commit = old.commit; if (!new->commit) die("You are on a branch yet to be born"); parse_commit(new->commit); } /* * If we were on a detached HEAD, but we are now moving to * a new commit, we want to mention the old commit once more * to remind the user that it might be lost. */ if (!opts->quiet && !old.path && old.commit && new->commit != old.commit) describe_detached_head("Previous HEAD position was", old.commit); if (!old.commit && !opts->force) { if (!opts->quiet) { fprintf(stderr, "warning: You appear to be on a branch yet to be born.\n"); fprintf(stderr, "warning: Forcing checkout of %s.\n", new->name); } opts->force = 1; } ret = merge_working_tree(opts, &old, new); if (ret) return ret; update_refs_for_switch(opts, &old, new); ret = post_checkout_hook(old.commit, new->commit, 1); return ret || opts->writeout_error; } static int git_checkout_config(const char *var, const char *value, void *cb) { return git_xmerge_config(var, value, cb); } int cmd_checkout(int argc, const char **argv, const char *prefix) { struct checkout_opts opts; unsigned char rev[20]; const char *arg; struct branch_info new; struct tree *source_tree = NULL; char *conflict_style = NULL; struct option options[] = { OPT__QUIET(&opts.quiet), OPT_STRING('b', NULL, &opts.new_branch, "new branch", "branch"), OPT_BOOLEAN('l', NULL, &opts.new_branch_log, "log for new branch"), OPT_SET_INT('t', "track", &opts.track, "track", BRANCH_TRACK_EXPLICIT), OPT_SET_INT('2', "ours", &opts.writeout_stage, "stage", 2), OPT_SET_INT('3', "theirs", &opts.writeout_stage, "stage", 3), OPT_BOOLEAN('f', NULL, &opts.force, "force"), OPT_BOOLEAN('m', "merge", &opts.merge, "merge"), OPT_STRING(0, "conflict", &conflict_style, "style", "conflict style (merge or diff3)"), OPT_END(), }; int has_dash_dash; memset(&opts, 0, sizeof(opts)); memset(&new, 0, sizeof(new)); git_config(git_checkout_config, NULL); opts.track = BRANCH_TRACK_UNSPECIFIED; argc = parse_options(argc, argv, options, checkout_usage, PARSE_OPT_KEEP_DASHDASH); /* --track without -b should DWIM */ if (0 < opts.track && !opts.new_branch) { const char *argv0 = argv[0]; if (!argc || !strcmp(argv0, "--")) die ("--track needs a branch name"); if (!prefixcmp(argv0, "refs/")) argv0 += 5; if (!prefixcmp(argv0, "remotes/")) argv0 += 8; argv0 = strchr(argv0, '/'); if (!argv0 || !argv0[1]) die ("Missing branch name; try -b"); opts.new_branch = argv0 + 1; } if (opts.track == BRANCH_TRACK_UNSPECIFIED) opts.track = git_branch_track; if (conflict_style) { opts.merge = 1; /* implied */ git_xmerge_config("merge.conflictstyle", conflict_style, NULL); } if (opts.force && opts.merge) die("git checkout: -f and -m are incompatible"); /* * case 1: git checkout <ref> -- [<paths>] * * <ref> must be a valid tree, everything after the '--' must be * a path. * * case 2: git checkout -- [<paths>] * * everything after the '--' must be paths. * * case 3: git checkout <something> [<paths>] * * With no paths, if <something> is a commit, that is to * switch to the branch or detach HEAD at it. * * Otherwise <something> shall not be ambiguous. * - If it's *only* a reference, treat it like case (1). * - If it's only a path, treat it like case (2). * - else: fail. * */ if (argc) { if (!strcmp(argv[0], "--")) { /* case (2) */ argv++; argc--; goto no_reference; } arg = argv[0]; has_dash_dash = (argc > 1) && !strcmp(argv[1], "--"); if (!strcmp(arg, "-")) arg = "@{-1}"; if (get_sha1(arg, rev)) { if (has_dash_dash) /* case (1) */ die("invalid reference: %s", arg); goto no_reference; /* case (3 -> 2) */ } /* we can't end up being in (2) anymore, eat the argument */ argv++; argc--; new.name = arg; if ((new.commit = lookup_commit_reference_gently(rev, 1))) { setup_branch_path(&new); if (resolve_ref(new.path, rev, 1, NULL)) new.commit = lookup_commit_reference(rev); else new.path = NULL; parse_commit(new.commit); source_tree = new.commit->tree; } else source_tree = parse_tree_indirect(rev); if (!source_tree) /* case (1): want a tree */ die("reference is not a tree: %s", arg); if (!has_dash_dash) {/* case (3 -> 1) */ /* * Do not complain the most common case * git checkout branch * even if there happen to be a file called 'branch'; * it would be extremely annoying. */ if (argc) verify_non_filename(NULL, arg); } else { argv++; argc--; } } no_reference: if (argc) { const char **pathspec = get_pathspec(prefix, argv); if (!pathspec) die("invalid path specification"); /* Checkout paths */ if (opts.new_branch) { if (argc == 1) { die("git checkout: updating paths is incompatible with switching branches.\nDid you intend to checkout '%s' which can not be resolved as commit?", argv[0]); } else { die("git checkout: updating paths is incompatible with switching branches."); } } if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge) die("git checkout: --ours/--theirs, --force and --merge are incompatible when\nchecking out of the index."); return checkout_paths(source_tree, pathspec, &opts); } if (opts.new_branch) { struct strbuf buf = STRBUF_INIT; strbuf_addstr(&buf, "refs/heads/"); strbuf_addstr(&buf, opts.new_branch); if (!get_sha1(buf.buf, rev)) die("git checkout: branch %s already exists", opts.new_branch); if (check_ref_format(buf.buf)) die("git checkout: we do not like '%s' as a branch name.", opts.new_branch); strbuf_release(&buf); } if (new.name && !new.commit) { die("Cannot switch branch to a non-commit."); } if (opts.writeout_stage) die("--ours/--theirs is incompatible with switching branches."); return switch_branches(&opts, &new); }