#include "cache.h" #include "commit.h" #include "refs.h" #include "diff.h" #include "diffcore.h" #include "xdiff-interface.h" #include "ll-merge.h" #include "dir.h" #include "notes.h" #include "notes-merge.h" #include "strbuf.h" #include "notes-utils.h" struct notes_merge_pair { struct object_id obj, base, local, remote; }; void init_notes_merge_options(struct notes_merge_options *o) { memset(o, 0, sizeof(struct notes_merge_options)); strbuf_init(&(o->commit_msg), 0); o->verbosity = NOTES_MERGE_VERBOSITY_DEFAULT; } static int path_to_oid(const char *path, struct object_id *oid) { char hex_oid[GIT_SHA1_HEXSZ]; int i = 0; while (*path && i < GIT_SHA1_HEXSZ) { if (*path != '/') hex_oid[i++] = *path; path++; } if (*path || i != GIT_SHA1_HEXSZ) return -1; return get_oid_hex(hex_oid, oid); } static int verify_notes_filepair(struct diff_filepair *p, struct object_id *oid) { switch (p->status) { case DIFF_STATUS_MODIFIED: assert(p->one->mode == p->two->mode); assert(!is_null_oid(&p->one->oid)); assert(!is_null_oid(&p->two->oid)); break; case DIFF_STATUS_ADDED: assert(is_null_oid(&p->one->oid)); break; case DIFF_STATUS_DELETED: assert(is_null_oid(&p->two->oid)); break; default: return -1; } assert(!strcmp(p->one->path, p->two->path)); return path_to_oid(p->one->path, oid); } static struct notes_merge_pair *find_notes_merge_pair_pos( struct notes_merge_pair *list, int len, struct object_id *obj, int insert_new, int *occupied) { /* * Both diff_tree_remote() and diff_tree_local() tend to process * merge_pairs in ascending order. Therefore, cache last returned * index, and search sequentially from there until the appropriate * position is found. * * Since inserts only happen from diff_tree_remote() (which mainly * _appends_), we don't care that inserting into the middle of the * list is expensive (using memmove()). */ static int last_index; int i = last_index < len ? last_index : len - 1; int prev_cmp = 0, cmp = -1; while (i >= 0 && i < len) { cmp = oidcmp(obj, &list[i].obj); if (!cmp) /* obj belongs @ i */ break; else if (cmp < 0 && prev_cmp <= 0) /* obj belongs < i */ i--; else if (cmp < 0) /* obj belongs between i-1 and i */ break; else if (cmp > 0 && prev_cmp >= 0) /* obj belongs > i */ i++; else /* if (cmp > 0) */ { /* obj belongs between i and i+1 */ i++; break; } prev_cmp = cmp; } if (i < 0) i = 0; /* obj belongs at, or immediately preceding, index i (0 <= i <= len) */ if (!cmp) *occupied = 1; else { *occupied = 0; if (insert_new && i < len) { MOVE_ARRAY(list + i + 1, list + i, len - i); memset(list + i, 0, sizeof(struct notes_merge_pair)); } } last_index = i; return list + i; } static struct object_id uninitialized = { "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" \ "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" }; static struct notes_merge_pair *diff_tree_remote(struct notes_merge_options *o, const struct object_id *base, const struct object_id *remote, int *num_changes) { struct diff_options opt; struct notes_merge_pair *changes; int i, len = 0; trace_printf("\tdiff_tree_remote(base = %.7s, remote = %.7s)\n", oid_to_hex(base), oid_to_hex(remote)); diff_setup(&opt); opt.flags.recursive = 1; opt.output_format = DIFF_FORMAT_NO_OUTPUT; diff_setup_done(&opt); diff_tree_oid(base, remote, "", &opt); diffcore_std(&opt); changes = xcalloc(diff_queued_diff.nr, sizeof(struct notes_merge_pair)); for (i = 0; i < diff_queued_diff.nr; i++) { struct diff_filepair *p = diff_queued_diff.queue[i]; struct notes_merge_pair *mp; int occupied; struct object_id obj; if (verify_notes_filepair(p, &obj)) { trace_printf("\t\tCannot merge entry '%s' (%c): " "%.7s -> %.7s. Skipping!\n", p->one->path, p->status, oid_to_hex(&p->one->oid), oid_to_hex(&p->two->oid)); continue; } mp = find_notes_merge_pair_pos(changes, len, &obj, 1, &occupied); if (occupied) { /* We've found an addition/deletion pair */ assert(!oidcmp(&mp->obj, &obj)); if (is_null_oid(&p->one->oid)) { /* addition */ assert(is_null_oid(&mp->remote)); oidcpy(&mp->remote, &p->two->oid); } else if (is_null_oid(&p->two->oid)) { /* deletion */ assert(is_null_oid(&mp->base)); oidcpy(&mp->base, &p->one->oid); } else assert(!"Invalid existing change recorded"); } else { oidcpy(&mp->obj, &obj); oidcpy(&mp->base, &p->one->oid); oidcpy(&mp->local, &uninitialized); oidcpy(&mp->remote, &p->two->oid); len++; } trace_printf("\t\tStored remote change for %s: %.7s -> %.7s\n", oid_to_hex(&mp->obj), oid_to_hex(&mp->base), oid_to_hex(&mp->remote)); } diff_flush(&opt); clear_pathspec(&opt.pathspec); *num_changes = len; return changes; } static void diff_tree_local(struct notes_merge_options *o, struct notes_merge_pair *changes, int len, const struct object_id *base, const struct object_id *local) { struct diff_options opt; int i; trace_printf("\tdiff_tree_local(len = %i, base = %.7s, local = %.7s)\n", len, oid_to_hex(base), oid_to_hex(local)); diff_setup(&opt); opt.flags.recursive = 1; opt.output_format = DIFF_FORMAT_NO_OUTPUT; diff_setup_done(&opt); diff_tree_oid(base, local, "", &opt); diffcore_std(&opt); for (i = 0; i < diff_queued_diff.nr; i++) { struct diff_filepair *p = diff_queued_diff.queue[i]; struct notes_merge_pair *mp; int match; struct object_id obj; if (verify_notes_filepair(p, &obj)) { trace_printf("\t\tCannot merge entry '%s' (%c): " "%.7s -> %.7s. Skipping!\n", p->one->path, p->status, oid_to_hex(&p->one->oid), oid_to_hex(&p->two->oid)); continue; } mp = find_notes_merge_pair_pos(changes, len, &obj, 0, &match); if (!match) { trace_printf("\t\tIgnoring local-only change for %s: " "%.7s -> %.7s\n", oid_to_hex(&obj), oid_to_hex(&p->one->oid), oid_to_hex(&p->two->oid)); continue; } assert(!oidcmp(&mp->obj, &obj)); if (is_null_oid(&p->two->oid)) { /* deletion */ /* * Either this is a true deletion (1), or it is part * of an A/D pair (2), or D/A pair (3): * * (1) mp->local is uninitialized; set it to null_sha1 * (2) mp->local is not uninitialized; don't touch it * (3) mp->local is uninitialized; set it to null_sha1 * (will be overwritten by following addition) */ if (!oidcmp(&mp->local, &uninitialized)) oidclr(&mp->local); } else if (is_null_oid(&p->one->oid)) { /* addition */ /* * Either this is a true addition (1), or it is part * of an A/D pair (2), or D/A pair (3): * * (1) mp->local is uninitialized; set to p->two->sha1 * (2) mp->local is uninitialized; set to p->two->sha1 * (3) mp->local is null_sha1; set to p->two->sha1 */ assert(is_null_oid(&mp->local) || !oidcmp(&mp->local, &uninitialized)); oidcpy(&mp->local, &p->two->oid); } else { /* modification */ /* * This is a true modification. p->one->sha1 shall * match mp->base, and mp->local shall be uninitialized. * Set mp->local to p->two->sha1. */ assert(!oidcmp(&p->one->oid, &mp->base)); assert(!oidcmp(&mp->local, &uninitialized)); oidcpy(&mp->local, &p->two->oid); } trace_printf("\t\tStored local change for %s: %.7s -> %.7s\n", oid_to_hex(&mp->obj), oid_to_hex(&mp->base), oid_to_hex(&mp->local)); } diff_flush(&opt); clear_pathspec(&opt.pathspec); } static void check_notes_merge_worktree(struct notes_merge_options *o) { if (!o->has_worktree) { /* * Must establish NOTES_MERGE_WORKTREE. * Abort if NOTES_MERGE_WORKTREE already exists */ if (file_exists(git_path(NOTES_MERGE_WORKTREE)) && !is_empty_dir(git_path(NOTES_MERGE_WORKTREE))) { if (advice_resolve_conflict) die(_("You have not concluded your previous " "notes merge (%s exists).\nPlease, use " "'git notes merge --commit' or 'git notes " "merge --abort' to commit/abort the " "previous merge before you start a new " "notes merge."), git_path("NOTES_MERGE_*")); else die(_("You have not concluded your notes merge " "(%s exists)."), git_path("NOTES_MERGE_*")); } if (safe_create_leading_directories_const(git_path( NOTES_MERGE_WORKTREE "/.test"))) die_errno("unable to create directory %s", git_path(NOTES_MERGE_WORKTREE)); o->has_worktree = 1; } else if (!file_exists(git_path(NOTES_MERGE_WORKTREE))) /* NOTES_MERGE_WORKTREE should already be established */ die("missing '%s'. This should not happen", git_path(NOTES_MERGE_WORKTREE)); } static void write_buf_to_worktree(const struct object_id *obj, const char *buf, unsigned long size) { int fd; char *path = git_pathdup(NOTES_MERGE_WORKTREE "/%s", oid_to_hex(obj)); if (safe_create_leading_directories_const(path)) die_errno("unable to create directory for '%s'", path); fd = xopen(path, O_WRONLY | O_EXCL | O_CREAT, 0666); while (size > 0) { ssize_t ret = write_in_full(fd, buf, size); if (ret < 0) { /* Ignore epipe */ if (errno == EPIPE) break; die_errno("notes-merge"); } size -= ret; buf += ret; } close(fd); free(path); } static void write_note_to_worktree(const struct object_id *obj, const struct object_id *note) { enum object_type type; unsigned long size; void *buf = read_object_file(note, &type, &size); if (!buf) die("cannot read note %s for object %s", oid_to_hex(note), oid_to_hex(obj)); if (type != OBJ_BLOB) die("blob expected in note %s for object %s", oid_to_hex(note), oid_to_hex(obj)); write_buf_to_worktree(obj, buf, size); free(buf); } static int ll_merge_in_worktree(struct notes_merge_options *o, struct notes_merge_pair *p) { mmbuffer_t result_buf; mmfile_t base, local, remote; int status; read_mmblob(&base, &p->base); read_mmblob(&local, &p->local); read_mmblob(&remote, &p->remote); status = ll_merge(&result_buf, oid_to_hex(&p->obj), &base, NULL, &local, o->local_ref, &remote, o->remote_ref, NULL); free(base.ptr); free(local.ptr); free(remote.ptr); if ((status < 0) || !result_buf.ptr) die("Failed to execute internal merge"); write_buf_to_worktree(&p->obj, result_buf.ptr, result_buf.size); free(result_buf.ptr); return status; } static int merge_one_change_manual(struct notes_merge_options *o, struct notes_merge_pair *p, struct notes_tree *t) { const char *lref = o->local_ref ? o->local_ref : "local version"; const char *rref = o->remote_ref ? o->remote_ref : "remote version"; trace_printf("\t\t\tmerge_one_change_manual(obj = %.7s, base = %.7s, " "local = %.7s, remote = %.7s)\n", oid_to_hex(&p->obj), oid_to_hex(&p->base), oid_to_hex(&p->local), oid_to_hex(&p->remote)); /* add "Conflicts:" section to commit message first time through */ if (!o->has_worktree) strbuf_addstr(&(o->commit_msg), "\n\nConflicts:\n"); strbuf_addf(&(o->commit_msg), "\t%s\n", oid_to_hex(&p->obj)); if (o->verbosity >= 2) printf("Auto-merging notes for %s\n", oid_to_hex(&p->obj)); check_notes_merge_worktree(o); if (is_null_oid(&p->local)) { /* D/F conflict, checkout p->remote */ assert(!is_null_oid(&p->remote)); if (o->verbosity >= 1) printf("CONFLICT (delete/modify): Notes for object %s " "deleted in %s and modified in %s. Version from %s " "left in tree.\n", oid_to_hex(&p->obj), lref, rref, rref); write_note_to_worktree(&p->obj, &p->remote); } else if (is_null_oid(&p->remote)) { /* D/F conflict, checkout p->local */ assert(!is_null_oid(&p->local)); if (o->verbosity >= 1) printf("CONFLICT (delete/modify): Notes for object %s " "deleted in %s and modified in %s. Version from %s " "left in tree.\n", oid_to_hex(&p->obj), rref, lref, lref); write_note_to_worktree(&p->obj, &p->local); } else { /* "regular" conflict, checkout result of ll_merge() */ const char *reason = "content"; if (is_null_oid(&p->base)) reason = "add/add"; assert(!is_null_oid(&p->local)); assert(!is_null_oid(&p->remote)); if (o->verbosity >= 1) printf("CONFLICT (%s): Merge conflict in notes for " "object %s\n", reason, oid_to_hex(&p->obj)); ll_merge_in_worktree(o, p); } trace_printf("\t\t\tremoving from partial merge result\n"); remove_note(t, p->obj.hash); return 1; } static int merge_one_change(struct notes_merge_options *o, struct notes_merge_pair *p, struct notes_tree *t) { /* * Return 0 if change is successfully resolved (stored in notes_tree). * Return 1 is change results in a conflict (NOT stored in notes_tree, * but instead written to NOTES_MERGE_WORKTREE with conflict markers). */ switch (o->strategy) { case NOTES_MERGE_RESOLVE_MANUAL: return merge_one_change_manual(o, p, t); case NOTES_MERGE_RESOLVE_OURS: if (o->verbosity >= 2) printf("Using local notes for %s\n", oid_to_hex(&p->obj)); /* nothing to do */ return 0; case NOTES_MERGE_RESOLVE_THEIRS: if (o->verbosity >= 2) printf("Using remote notes for %s\n", oid_to_hex(&p->obj)); if (add_note(t, &p->obj, &p->remote, combine_notes_overwrite)) die("BUG: combine_notes_overwrite failed"); return 0; case NOTES_MERGE_RESOLVE_UNION: if (o->verbosity >= 2) printf("Concatenating local and remote notes for %s\n", oid_to_hex(&p->obj)); if (add_note(t, &p->obj, &p->remote, combine_notes_concatenate)) die("failed to concatenate notes " "(combine_notes_concatenate)"); return 0; case NOTES_MERGE_RESOLVE_CAT_SORT_UNIQ: if (o->verbosity >= 2) printf("Concatenating unique lines in local and remote " "notes for %s\n", oid_to_hex(&p->obj)); if (add_note(t, &p->obj, &p->remote, combine_notes_cat_sort_uniq)) die("failed to concatenate notes " "(combine_notes_cat_sort_uniq)"); return 0; } die("Unknown strategy (%i).", o->strategy); } static int merge_changes(struct notes_merge_options *o, struct notes_merge_pair *changes, int *num_changes, struct notes_tree *t) { int i, conflicts = 0; trace_printf("\tmerge_changes(num_changes = %i)\n", *num_changes); for (i = 0; i < *num_changes; i++) { struct notes_merge_pair *p = changes + i; trace_printf("\t\t%.7s: %.7s -> %.7s/%.7s\n", oid_to_hex(&p->obj), oid_to_hex(&p->base), oid_to_hex(&p->local), oid_to_hex(&p->remote)); if (!oidcmp(&p->base, &p->remote)) { /* no remote change; nothing to do */ trace_printf("\t\t\tskipping (no remote change)\n"); } else if (!oidcmp(&p->local, &p->remote)) { /* same change in local and remote; nothing to do */ trace_printf("\t\t\tskipping (local == remote)\n"); } else if (!oidcmp(&p->local, &uninitialized) || !oidcmp(&p->local, &p->base)) { /* no local change; adopt remote change */ trace_printf("\t\t\tno local change, adopted remote\n"); if (add_note(t, &p->obj, &p->remote, combine_notes_overwrite)) die("BUG: combine_notes_overwrite failed"); } else { /* need file-level merge between local and remote */ trace_printf("\t\t\tneed content-level merge\n"); conflicts += merge_one_change(o, p, t); } } return conflicts; } static int merge_from_diffs(struct notes_merge_options *o, const struct object_id *base, const struct object_id *local, const struct object_id *remote, struct notes_tree *t) { struct notes_merge_pair *changes; int num_changes, conflicts; trace_printf("\tmerge_from_diffs(base = %.7s, local = %.7s, " "remote = %.7s)\n", oid_to_hex(base), oid_to_hex(local), oid_to_hex(remote)); changes = diff_tree_remote(o, base, remote, &num_changes); diff_tree_local(o, changes, num_changes, base, local); conflicts = merge_changes(o, changes, &num_changes, t); free(changes); if (o->verbosity >= 4) printf(t->dirty ? "Merge result: %i unmerged notes and a dirty notes tree\n" : "Merge result: %i unmerged notes and a clean notes tree\n", conflicts); return conflicts ? -1 : 1; } int notes_merge(struct notes_merge_options *o, struct notes_tree *local_tree, struct object_id *result_oid) { struct object_id local_oid, remote_oid; struct commit *local, *remote; struct commit_list *bases = NULL; const struct object_id *base_oid, *base_tree_oid; int result = 0; assert(o->local_ref && o->remote_ref); assert(!strcmp(o->local_ref, local_tree->ref)); oidclr(result_oid); trace_printf("notes_merge(o->local_ref = %s, o->remote_ref = %s)\n", o->local_ref, o->remote_ref); /* Dereference o->local_ref into local_sha1 */ if (read_ref_full(o->local_ref, 0, &local_oid, NULL)) die("Failed to resolve local notes ref '%s'", o->local_ref); else if (!check_refname_format(o->local_ref, 0) && is_null_oid(&local_oid)) local = NULL; /* local_oid == null_oid indicates unborn ref */ else if (!(local = lookup_commit_reference(&local_oid))) die("Could not parse local commit %s (%s)", oid_to_hex(&local_oid), o->local_ref); trace_printf("\tlocal commit: %.7s\n", oid_to_hex(&local_oid)); /* Dereference o->remote_ref into remote_oid */ if (get_oid(o->remote_ref, &remote_oid)) { /* * Failed to get remote_oid. If o->remote_ref looks like an * unborn ref, perform the merge using an empty notes tree. */ if (!check_refname_format(o->remote_ref, 0)) { oidclr(&remote_oid); remote = NULL; } else { die("Failed to resolve remote notes ref '%s'", o->remote_ref); } } else if (!(remote = lookup_commit_reference(&remote_oid))) { die("Could not parse remote commit %s (%s)", oid_to_hex(&remote_oid), o->remote_ref); } trace_printf("\tremote commit: %.7s\n", oid_to_hex(&remote_oid)); if (!local && !remote) die("Cannot merge empty notes ref (%s) into empty notes ref " "(%s)", o->remote_ref, o->local_ref); if (!local) { /* result == remote commit */ oidcpy(result_oid, &remote_oid); goto found_result; } if (!remote) { /* result == local commit */ oidcpy(result_oid, &local_oid); goto found_result; } assert(local && remote); /* Find merge bases */ bases = get_merge_bases(local, remote); if (!bases) { base_oid = &null_oid; base_tree_oid = the_hash_algo->empty_tree; if (o->verbosity >= 4) printf("No merge base found; doing history-less merge\n"); } else if (!bases->next) { base_oid = &bases->item->object.oid; base_tree_oid = &bases->item->tree->object.oid; if (o->verbosity >= 4) printf("One merge base found (%.7s)\n", oid_to_hex(base_oid)); } else { /* TODO: How to handle multiple merge-bases? */ base_oid = &bases->item->object.oid; base_tree_oid = &bases->item->tree->object.oid; if (o->verbosity >= 3) printf("Multiple merge bases found. Using the first " "(%.7s)\n", oid_to_hex(base_oid)); } if (o->verbosity >= 4) printf("Merging remote commit %.7s into local commit %.7s with " "merge-base %.7s\n", oid_to_hex(&remote->object.oid), oid_to_hex(&local->object.oid), oid_to_hex(base_oid)); if (!oidcmp(&remote->object.oid, base_oid)) { /* Already merged; result == local commit */ if (o->verbosity >= 2) printf("Already up to date!\n"); oidcpy(result_oid, &local->object.oid); goto found_result; } if (!oidcmp(&local->object.oid, base_oid)) { /* Fast-forward; result == remote commit */ if (o->verbosity >= 2) printf("Fast-forward\n"); oidcpy(result_oid, &remote->object.oid); goto found_result; } result = merge_from_diffs(o, base_tree_oid, &local->tree->object.oid, &remote->tree->object.oid, local_tree); if (result != 0) { /* non-trivial merge (with or without conflicts) */ /* Commit (partial) result */ struct commit_list *parents = NULL; commit_list_insert(remote, &parents); /* LIFO order */ commit_list_insert(local, &parents); create_notes_commit(local_tree, parents, o->commit_msg.buf, o->commit_msg.len, result_oid); } found_result: free_commit_list(bases); strbuf_release(&(o->commit_msg)); trace_printf("notes_merge(): result = %i, result_oid = %.7s\n", result, oid_to_hex(result_oid)); return result; } int notes_merge_commit(struct notes_merge_options *o, struct notes_tree *partial_tree, struct commit *partial_commit, struct object_id *result_oid) { /* * Iterate through files in .git/NOTES_MERGE_WORKTREE and add all * found notes to 'partial_tree'. Write the updated notes tree to * the DB, and commit the resulting tree object while reusing the * commit message and parents from 'partial_commit'. * Finally store the new commit object OID into 'result_oid'. */ DIR *dir; struct dirent *e; struct strbuf path = STRBUF_INIT; const char *buffer = get_commit_buffer(partial_commit, NULL); const char *msg = strstr(buffer, "\n\n"); int baselen; git_path_buf(&path, NOTES_MERGE_WORKTREE); if (o->verbosity >= 3) printf("Committing notes in notes merge worktree at %s\n", path.buf); if (!msg || msg[2] == '\0') die("partial notes commit has empty message"); msg += 2; dir = opendir(path.buf); if (!dir) die_errno("could not open %s", path.buf); strbuf_addch(&path, '/'); baselen = path.len; while ((e = readdir(dir)) != NULL) { struct stat st; struct object_id obj_oid, blob_oid; if (is_dot_or_dotdot(e->d_name)) continue; if (get_oid_hex(e->d_name, &obj_oid)) { if (o->verbosity >= 3) printf("Skipping non-SHA1 entry '%s%s'\n", path.buf, e->d_name); continue; } strbuf_addstr(&path, e->d_name); /* write file as blob, and add to partial_tree */ if (stat(path.buf, &st)) die_errno("Failed to stat '%s'", path.buf); if (index_path(&blob_oid, path.buf, &st, HASH_WRITE_OBJECT)) die("Failed to write blob object from '%s'", path.buf); if (add_note(partial_tree, &obj_oid, &blob_oid, NULL)) die("Failed to add resolved note '%s' to notes tree", path.buf); if (o->verbosity >= 4) printf("Added resolved note for object %s: %s\n", oid_to_hex(&obj_oid), oid_to_hex(&blob_oid)); strbuf_setlen(&path, baselen); } create_notes_commit(partial_tree, partial_commit->parents, msg, strlen(msg), result_oid); unuse_commit_buffer(partial_commit, buffer); if (o->verbosity >= 4) printf("Finalized notes merge commit: %s\n", oid_to_hex(result_oid)); strbuf_release(&path); closedir(dir); return 0; } int notes_merge_abort(struct notes_merge_options *o) { /* * Remove all files within .git/NOTES_MERGE_WORKTREE. We do not remove * the .git/NOTES_MERGE_WORKTREE directory itself, since it might be * the current working directory of the user. */ struct strbuf buf = STRBUF_INIT; int ret; git_path_buf(&buf, NOTES_MERGE_WORKTREE); if (o->verbosity >= 3) printf("Removing notes merge worktree at %s/*\n", buf.buf); ret = remove_dir_recursively(&buf, REMOVE_DIR_KEEP_TOPLEVEL); strbuf_release(&buf); return ret; }