diff options
Diffstat (limited to 'revision.c')
| -rw-r--r-- | revision.c | 811 |
1 files changed, 811 insertions, 0 deletions
diff --git a/revision.c b/revision.c new file mode 100644 index 0000000..ce35b5a --- /dev/null +++ b/revision.c @@ -0,0 +1,811 @@ +#include "cache.h" +#include "tag.h" +#include "blob.h" +#include "tree.h" +#include "commit.h" +#include "diff.h" +#include "refs.h" +#include "revision.h" + +static char *path_name(struct name_path *path, const char *name) +{ + struct name_path *p; + char *n, *m; + int nlen = strlen(name); + int len = nlen + 1; + + for (p = path; p; p = p->up) { + if (p->elem_len) + len += p->elem_len + 1; + } + n = xmalloc(len); + m = n + len - (nlen + 1); + strcpy(m, name); + for (p = path; p; p = p->up) { + if (p->elem_len) { + m -= p->elem_len + 1; + memcpy(m, p->elem, p->elem_len); + m[p->elem_len] = '/'; + } + } + return n; +} + +struct object_list **add_object(struct object *obj, + struct object_list **p, + struct name_path *path, + const char *name) +{ + struct object_list *entry = xmalloc(sizeof(*entry)); + entry->item = obj; + entry->next = *p; + entry->name = path_name(path, name); + *p = entry; + return &entry->next; +} + +static void mark_blob_uninteresting(struct blob *blob) +{ + if (blob->object.flags & UNINTERESTING) + return; + blob->object.flags |= UNINTERESTING; +} + +void mark_tree_uninteresting(struct tree *tree) +{ + struct object *obj = &tree->object; + struct tree_entry_list *entry; + + if (obj->flags & UNINTERESTING) + return; + obj->flags |= UNINTERESTING; + if (!has_sha1_file(obj->sha1)) + return; + if (parse_tree(tree) < 0) + die("bad tree %s", sha1_to_hex(obj->sha1)); + entry = tree->entries; + tree->entries = NULL; + while (entry) { + struct tree_entry_list *next = entry->next; + if (entry->directory) + mark_tree_uninteresting(entry->item.tree); + else + mark_blob_uninteresting(entry->item.blob); + free(entry); + entry = next; + } +} + +void mark_parents_uninteresting(struct commit *commit) +{ + struct commit_list *parents = commit->parents; + + while (parents) { + struct commit *commit = parents->item; + if (!(commit->object.flags & UNINTERESTING)) { + commit->object.flags |= UNINTERESTING; + + /* + * Normally we haven't parsed the parent + * yet, so we won't have a parent of a parent + * here. However, it may turn out that we've + * reached this commit some other way (where it + * wasn't uninteresting), in which case we need + * to mark its parents recursively too.. + */ + if (commit->parents) + mark_parents_uninteresting(commit); + } + + /* + * A missing commit is ok iff its parent is marked + * uninteresting. + * + * We just mark such a thing parsed, so that when + * it is popped next time around, we won't be trying + * to parse it and get an error. + */ + if (!has_sha1_file(commit->object.sha1)) + commit->object.parsed = 1; + parents = parents->next; + } +} + +static void add_pending_object(struct rev_info *revs, struct object *obj, const char *name) +{ + add_object(obj, &revs->pending_objects, NULL, name); +} + +static struct commit *get_commit_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags) +{ + struct object *object; + + object = parse_object(sha1); + if (!object) + die("bad object %s", name); + + /* + * Tag object? Look what it points to.. + */ + while (object->type == tag_type) { + struct tag *tag = (struct tag *) object; + object->flags |= flags; + if (revs->tag_objects && !(object->flags & UNINTERESTING)) + add_pending_object(revs, object, tag->tag); + object = parse_object(tag->tagged->sha1); + if (!object) + die("bad object %s", sha1_to_hex(tag->tagged->sha1)); + } + + /* + * Commit object? Just return it, we'll do all the complex + * reachability crud. + */ + if (object->type == commit_type) { + struct commit *commit = (struct commit *)object; + object->flags |= flags; + if (parse_commit(commit) < 0) + die("unable to parse commit %s", name); + if (flags & UNINTERESTING) { + mark_parents_uninteresting(commit); + revs->limited = 1; + } + return commit; + } + + /* + * Tree object? Either mark it uniniteresting, or add it + * to the list of objects to look at later.. + */ + if (object->type == tree_type) { + struct tree *tree = (struct tree *)object; + if (!revs->tree_objects) + return NULL; + if (flags & UNINTERESTING) { + mark_tree_uninteresting(tree); + return NULL; + } + add_pending_object(revs, object, ""); + return NULL; + } + + /* + * Blob object? You know the drill by now.. + */ + if (object->type == blob_type) { + struct blob *blob = (struct blob *)object; + if (!revs->blob_objects) + return NULL; + if (flags & UNINTERESTING) { + mark_blob_uninteresting(blob); + return NULL; + } + add_pending_object(revs, object, ""); + return NULL; + } + die("%s is unknown object", name); +} + +static int everybody_uninteresting(struct commit_list *orig) +{ + struct commit_list *list = orig; + while (list) { + struct commit *commit = list->item; + list = list->next; + if (commit->object.flags & UNINTERESTING) + continue; + return 0; + } + return 1; +} + +static int tree_difference = REV_TREE_SAME; + +static void file_add_remove(struct diff_options *options, + int addremove, unsigned mode, + const unsigned char *sha1, + const char *base, const char *path) +{ + int diff = REV_TREE_DIFFERENT; + + /* + * Is it an add of a new file? It means that the old tree + * didn't have it at all, so we will turn "REV_TREE_SAME" -> + * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone + * (and if it already was "REV_TREE_NEW", we'll keep it + * "REV_TREE_NEW" of course). + */ + if (addremove == '+') { + diff = tree_difference; + if (diff != REV_TREE_SAME) + return; + diff = REV_TREE_NEW; + } + tree_difference = diff; +} + +static void file_change(struct diff_options *options, + unsigned old_mode, unsigned new_mode, + const unsigned char *old_sha1, + const unsigned char *new_sha1, + const char *base, const char *path) +{ + tree_difference = REV_TREE_DIFFERENT; +} + +static struct diff_options diff_opt = { + .recursive = 1, + .add_remove = file_add_remove, + .change = file_change, +}; + +int rev_compare_tree(struct tree *t1, struct tree *t2) +{ + if (!t1) + return REV_TREE_NEW; + if (!t2) + return REV_TREE_DIFFERENT; + tree_difference = REV_TREE_SAME; + if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0) + return REV_TREE_DIFFERENT; + return tree_difference; +} + +int rev_same_tree_as_empty(struct tree *t1) +{ + int retval; + void *tree; + struct tree_desc empty, real; + + if (!t1) + return 0; + + tree = read_object_with_reference(t1->object.sha1, tree_type, &real.size, NULL); + if (!tree) + return 0; + real.buf = tree; + + empty.buf = ""; + empty.size = 0; + + tree_difference = 0; + retval = diff_tree(&empty, &real, "", &diff_opt); + free(tree); + + return retval >= 0 && !tree_difference; +} + +static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit) +{ + struct commit_list **pp, *parent; + int tree_changed = 0; + + if (!commit->tree) + return; + + if (!commit->parents) { + if (!rev_same_tree_as_empty(commit->tree)) + commit->object.flags |= TREECHANGE; + return; + } + + pp = &commit->parents; + while ((parent = *pp) != NULL) { + struct commit *p = parent->item; + + parse_commit(p); + switch (rev_compare_tree(p->tree, commit->tree)) { + case REV_TREE_SAME: + if (p->object.flags & UNINTERESTING) { + /* Even if a merge with an uninteresting + * side branch brought the entire change + * we are interested in, we do not want + * to lose the other branches of this + * merge, so we just keep going. + */ + pp = &parent->next; + continue; + } + parent->next = NULL; + commit->parents = parent; + return; + + case REV_TREE_NEW: + if (revs->remove_empty_trees && + rev_same_tree_as_empty(p->tree)) { + /* We are adding all the specified + * paths from this parent, so the + * history beyond this parent is not + * interesting. Remove its parents + * (they are grandparents for us). + * IOW, we pretend this parent is a + * "root" commit. + */ + parse_commit(p); + p->parents = NULL; + } + /* fallthrough */ + case REV_TREE_DIFFERENT: + tree_changed = 1; + pp = &parent->next; + continue; + } + die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1)); + } + if (tree_changed) + commit->object.flags |= TREECHANGE; +} + +static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list) +{ + struct commit_list *parent = commit->parents; + + /* + * If the commit is uninteresting, don't try to + * prune parents - we want the maximal uninteresting + * set. + * + * Normally we haven't parsed the parent + * yet, so we won't have a parent of a parent + * here. However, it may turn out that we've + * reached this commit some other way (where it + * wasn't uninteresting), in which case we need + * to mark its parents recursively too.. + */ + if (commit->object.flags & UNINTERESTING) { + while (parent) { + struct commit *p = parent->item; + parent = parent->next; + parse_commit(p); + p->object.flags |= UNINTERESTING; + if (p->parents) + mark_parents_uninteresting(p); + if (p->object.flags & SEEN) + continue; + p->object.flags |= SEEN; + insert_by_date(p, list); + } + return; + } + + /* + * Ok, the commit wasn't uninteresting. Try to + * simplify the commit history and find the parent + * that has no differences in the path set if one exists. + */ + if (revs->prune_fn) + revs->prune_fn(revs, commit); + + parent = commit->parents; + while (parent) { + struct commit *p = parent->item; + + parent = parent->next; + + parse_commit(p); + if (p->object.flags & SEEN) + continue; + p->object.flags |= SEEN; + insert_by_date(p, list); + } +} + +static void limit_list(struct rev_info *revs) +{ + struct commit_list *list = revs->commits; + struct commit_list *newlist = NULL; + struct commit_list **p = &newlist; + + while (list) { + struct commit_list *entry = list; + struct commit *commit = list->item; + struct object *obj = &commit->object; + + list = list->next; + free(entry); + + if (revs->max_age != -1 && (commit->date < revs->max_age)) + obj->flags |= UNINTERESTING; + if (revs->unpacked && has_sha1_pack(obj->sha1)) + obj->flags |= UNINTERESTING; + add_parents_to_list(revs, commit, &list); + if (obj->flags & UNINTERESTING) { + mark_parents_uninteresting(commit); + if (everybody_uninteresting(list)) + break; + continue; + } + if (revs->min_age != -1 && (commit->date > revs->min_age)) + continue; + p = &commit_list_insert(commit, p)->next; + } + if (revs->boundary) { + /* mark the ones that are on the result list first */ + for (list = newlist; list; list = list->next) { + struct commit *commit = list->item; + commit->object.flags |= TMP_MARK; + } + for (list = newlist; list; list = list->next) { + struct commit *commit = list->item; + struct object *obj = &commit->object; + struct commit_list *parent; + if (obj->flags & UNINTERESTING) + continue; + for (parent = commit->parents; + parent; + parent = parent->next) { + struct commit *pcommit = parent->item; + if (!(pcommit->object.flags & UNINTERESTING)) + continue; + pcommit->object.flags |= BOUNDARY; + if (pcommit->object.flags & TMP_MARK) + continue; + pcommit->object.flags |= TMP_MARK; + p = &commit_list_insert(pcommit, p)->next; + } + } + for (list = newlist; list; list = list->next) { + struct commit *commit = list->item; + commit->object.flags &= ~TMP_MARK; + } + } + revs->commits = newlist; +} + +static void add_one_commit(struct commit *commit, struct rev_info *revs) +{ + if (!commit || (commit->object.flags & SEEN)) + return; + commit->object.flags |= SEEN; + commit_list_insert(commit, &revs->commits); +} + +static int all_flags; +static struct rev_info *all_revs; + +static int handle_one_ref(const char *path, const unsigned char *sha1) +{ + struct commit *commit = get_commit_reference(all_revs, path, sha1, all_flags); + add_one_commit(commit, all_revs); + return 0; +} + +static void handle_all(struct rev_info *revs, unsigned flags) +{ + all_revs = revs; + all_flags = flags; + for_each_ref(handle_one_ref); +} + +void init_revisions(struct rev_info *revs) +{ + memset(revs, 0, sizeof(*revs)); + revs->lifo = 1; + revs->dense = 1; + revs->prefix = setup_git_directory(); + revs->max_age = -1; + revs->min_age = -1; + revs->max_count = -1; + + revs->prune_fn = NULL; + revs->prune_data = NULL; + + revs->topo_setter = topo_sort_default_setter; + revs->topo_getter = topo_sort_default_getter; +} + +/* + * Parse revision information, filling in the "rev_info" structure, + * and removing the used arguments from the argument list. + * + * Returns the number of arguments left that weren't recognized + * (which are also moved to the head of the argument list) + */ +int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def) +{ + int i, flags, seen_dashdash; + const char **unrecognized = argv + 1; + int left = 1; + + init_revisions(revs); + + /* First, search for "--" */ + seen_dashdash = 0; + for (i = 1; i < argc; i++) { + const char *arg = argv[i]; + if (strcmp(arg, "--")) + continue; + argv[i] = NULL; + argc = i; + revs->prune_data = get_pathspec(revs->prefix, argv + i + 1); + seen_dashdash = 1; + break; + } + + flags = 0; + for (i = 1; i < argc; i++) { + struct commit *commit; + const char *arg = argv[i]; + unsigned char sha1[20]; + char *dotdot; + int local_flags; + + if (*arg == '-') { + if (!strncmp(arg, "--max-count=", 12)) { + revs->max_count = atoi(arg + 12); + continue; + } + /* accept -<digit>, like traditilnal "head" */ + if ((*arg == '-') && isdigit(arg[1])) { + revs->max_count = atoi(arg + 1); + continue; + } + if (!strcmp(arg, "-n")) { + if (argc <= i + 1) + die("-n requires an argument"); + revs->max_count = atoi(argv[++i]); + continue; + } + if (!strncmp(arg,"-n",2)) { + revs->max_count = atoi(arg + 2); + continue; + } + if (!strncmp(arg, "--max-age=", 10)) { + revs->max_age = atoi(arg + 10); + continue; + } + if (!strncmp(arg, "--since=", 8)) { + revs->max_age = approxidate(arg + 8); + continue; + } + if (!strncmp(arg, "--after=", 8)) { + revs->max_age = approxidate(arg + 8); + continue; + } + if (!strncmp(arg, "--min-age=", 10)) { + revs->min_age = atoi(arg + 10); + continue; + } + if (!strncmp(arg, "--before=", 9)) { + revs->min_age = approxidate(arg + 9); + continue; + } + if (!strncmp(arg, "--until=", 8)) { + revs->min_age = approxidate(arg + 8); + continue; + } + if (!strcmp(arg, "--all")) { + handle_all(revs, flags); + continue; + } + if (!strcmp(arg, "--not")) { + flags ^= UNINTERESTING; + continue; + } + if (!strcmp(arg, "--default")) { + if (++i >= argc) + die("bad --default argument"); + def = argv[i]; + continue; + } + if (!strcmp(arg, "--topo-order")) { + revs->topo_order = 1; + continue; + } + if (!strcmp(arg, "--date-order")) { + revs->lifo = 0; + revs->topo_order = 1; + continue; + } + if (!strcmp(arg, "--parents")) { + revs->parents = 1; + continue; + } + if (!strcmp(arg, "--dense")) { + revs->dense = 1; + continue; + } + if (!strcmp(arg, "--sparse")) { + revs->dense = 0; + continue; + } + if (!strcmp(arg, "--remove-empty")) { + revs->remove_empty_trees = 1; + continue; + } + if (!strcmp(arg, "--no-merges")) { + revs->no_merges = 1; + continue; + } + if (!strcmp(arg, "--boundary")) { + revs->boundary = 1; + continue; + } + if (!strcmp(arg, "--objects")) { + revs->tag_objects = 1; + revs->tree_objects = 1; + revs->blob_objects = 1; + continue; + } + if (!strcmp(arg, "--objects-edge")) { + revs->tag_objects = 1; + revs->tree_objects = 1; + revs->blob_objects = 1; + revs->edge_hint = 1; + continue; + } + if (!strcmp(arg, "--unpacked")) { + revs->unpacked = 1; + continue; + } + *unrecognized++ = arg; + left++; + continue; + } + dotdot = strstr(arg, ".."); + if (dotdot) { + unsigned char from_sha1[20]; + const char *next = dotdot + 2; + const char *this = arg; + *dotdot = 0; + if (!*next) + next = "HEAD"; + if (dotdot == arg) + this = "HEAD"; + if (!get_sha1(this, from_sha1) && + !get_sha1(next, sha1)) { + struct commit *exclude; + struct commit *include; + + exclude = get_commit_reference(revs, this, from_sha1, flags ^ UNINTERESTING); + include = get_commit_reference(revs, next, sha1, flags); + if (!exclude || !include) + die("Invalid revision range %s..%s", arg, next); + add_one_commit(exclude, revs); + add_one_commit(include, revs); + continue; + } + *dotdot = '.'; + } + local_flags = 0; + if (*arg == '^') { + local_flags = UNINTERESTING; + arg++; + } + if (get_sha1(arg, sha1) < 0) { + struct stat st; + int j; + + if (seen_dashdash || local_flags) + die("bad revision '%s'", arg); + + /* If we didn't have a "--", all filenames must exist */ + for (j = i; j < argc; j++) { + if (lstat(argv[j], &st) < 0) + die("'%s': %s", argv[j], strerror(errno)); + } + revs->prune_data = get_pathspec(revs->prefix, argv + i); + break; + } + commit = get_commit_reference(revs, arg, sha1, flags ^ local_flags); + add_one_commit(commit, revs); + } + if (def && !revs->commits) { + unsigned char sha1[20]; + struct commit *commit; + if (get_sha1(def, sha1) < 0) + die("bad default revision '%s'", def); + commit = get_commit_reference(revs, def, sha1, 0); + add_one_commit(commit, revs); + } + + if (revs->topo_order || revs->unpacked) + revs->limited = 1; + + if (revs->prune_data) { + diff_tree_setup_paths(revs->prune_data); + revs->prune_fn = try_to_simplify_commit; + + /* + * If we fix up parent data, we currently cannot + * do that on-the-fly. + */ + if (revs->parents) + revs->limited = 1; + } + + return left; +} + +void prepare_revision_walk(struct rev_info *revs) +{ + sort_by_date(&revs->commits); + if (revs->limited) + limit_list(revs); + if (revs->topo_order) + sort_in_topological_order_fn(&revs->commits, revs->lifo, + revs->topo_setter, + revs->topo_getter); +} + +static int rewrite_one(struct commit **pp) +{ + for (;;) { + struct commit *p = *pp; + if (p->object.flags & (TREECHANGE | UNINTERESTING)) + return 0; + if (!p->parents) + return -1; + *pp = p->parents->item; + } +} + +static void rewrite_parents(struct commit *commit) +{ + struct commit_list **pp = &commit->parents; + while (*pp) { + struct commit_list *parent = *pp; + if (rewrite_one(&parent->item) < 0) { + *pp = parent->next; + continue; + } + pp = &parent->next; + } +} + +struct commit *get_revision(struct rev_info *revs) +{ + struct commit_list *list = revs->commits; + + if (!list) + return NULL; + + /* Check the max_count ... */ + switch (revs->max_count) { + case -1: + break; + case 0: + return NULL; + default: + revs->max_count--; + } + + do { + struct commit *commit = revs->commits->item; + + revs->commits = revs->commits->next; + + /* + * If we haven't done the list limiting, we need to look at + * the parents here. We also need to do the date-based limiting + * that we'd otherwise have done in limit_list(). + */ + if (!revs->limited) { + if ((revs->unpacked && + has_sha1_pack(commit->object.sha1)) || + (revs->max_age != -1 && + (commit->date < revs->max_age))) + continue; + add_parents_to_list(revs, commit, &revs->commits); + } + if (commit->object.flags & SHOWN) + continue; + if (!(commit->object.flags & BOUNDARY) && + (commit->object.flags & UNINTERESTING)) + continue; + if (revs->min_age != -1 && (commit->date > revs->min_age)) + continue; + if (revs->no_merges && + commit->parents && commit->parents->next) + continue; + if (revs->prune_fn && revs->dense) { + if (!(commit->object.flags & TREECHANGE)) + continue; + if (revs->parents) + rewrite_parents(commit); + } + commit->object.flags |= SHOWN; + return commit; + } while (revs->commits); + return NULL; +} |