/* * Copyright (C) the libgit2 contributors. All rights reserved. * * This file is part of libgit2, distributed under the GNU GPL v2 with * a Linking Exception. For full terms see the included COPYING file. */ #include "common.h" #include "commit.h" #include "tree.h" #include "git2/repository.h" #include "git2/object.h" #define DEFAULT_TREE_SIZE 16 #define MAX_FILEMODE_BYTES 6 static bool valid_filemode(const int filemode) { return (filemode == GIT_FILEMODE_TREE || filemode == GIT_FILEMODE_BLOB || filemode == GIT_FILEMODE_BLOB_EXECUTABLE || filemode == GIT_FILEMODE_LINK || filemode == GIT_FILEMODE_COMMIT); } GIT_INLINE(git_filemode_t) normalize_filemode(git_filemode_t filemode) { /* Tree bits set, but it's not a commit */ if (filemode & GIT_FILEMODE_TREE && !(filemode & 0100000)) return GIT_FILEMODE_TREE; /* If any of the x bits is set */ if (filemode & 0111) return GIT_FILEMODE_BLOB_EXECUTABLE; /* 16XXXX means commit */ if ((filemode & GIT_FILEMODE_COMMIT) == GIT_FILEMODE_COMMIT) return GIT_FILEMODE_COMMIT; /* 12XXXX means commit */ if ((filemode & GIT_FILEMODE_LINK) == GIT_FILEMODE_LINK) return GIT_FILEMODE_LINK; /* Otherwise, return a blob */ return GIT_FILEMODE_BLOB; } static int valid_entry_name(const char *filename) { return *filename != '\0' && strchr(filename, '/') == NULL && (*filename != '.' || (strcmp(filename, ".") != 0 && strcmp(filename, "..") != 0 && strcmp(filename, DOT_GIT) != 0)); } static int entry_sort_cmp(const void *a, const void *b) { const git_tree_entry *e1 = (const git_tree_entry *)a; const git_tree_entry *e2 = (const git_tree_entry *)b; return git_path_cmp( e1->filename, e1->filename_len, git_tree_entry__is_tree(e1), e2->filename, e2->filename_len, git_tree_entry__is_tree(e2), git__strncmp); } int git_tree_entry_cmp(const git_tree_entry *e1, const git_tree_entry *e2) { return entry_sort_cmp(e1, e2); } int git_tree_entry_icmp(const git_tree_entry *e1, const git_tree_entry *e2) { return git_path_cmp( e1->filename, e1->filename_len, git_tree_entry__is_tree(e1), e2->filename, e2->filename_len, git_tree_entry__is_tree(e2), git__strncasecmp); } static git_tree_entry *alloc_entry(const char *filename) { git_tree_entry *entry = NULL; size_t filename_len = strlen(filename); entry = git__malloc(sizeof(git_tree_entry) + filename_len + 1); if (!entry) return NULL; memset(entry, 0x0, sizeof(git_tree_entry)); memcpy(entry->filename, filename, filename_len); entry->filename[filename_len] = 0; entry->filename_len = filename_len; return entry; } struct tree_key_search { const char *filename; size_t filename_len; }; static int homing_search_cmp(const void *key, const void *array_member) { const struct tree_key_search *ksearch = key; const git_tree_entry *entry = array_member; const size_t len1 = ksearch->filename_len; const size_t len2 = entry->filename_len; return memcmp( ksearch->filename, entry->filename, len1 < len2 ? len1 : len2 ); } /* * Search for an entry in a given tree. * * Note that this search is performed in two steps because * of the way tree entries are sorted internally in git: * * Entries in a tree are not sorted alphabetically; two entries * with the same root prefix will have different positions * depending on whether they are folders (subtrees) or normal files. * * Consequently, it is not possible to find an entry on the tree * with a binary search if you don't know whether the filename * you're looking for is a folder or a normal file. * * To work around this, we first perform a homing binary search * on the tree, using the minimal length root prefix of our filename. * Once the comparisons for this homing search start becoming * ambiguous because of folder vs file sorting, we look linearly * around the area for our target file. */ static int tree_key_search( size_t *at_pos, git_vector *entries, const char *filename, size_t filename_len) { struct tree_key_search ksearch; const git_tree_entry *entry; size_t homing, i; ksearch.filename = filename; ksearch.filename_len = filename_len; /* Initial homing search; find an entry on the tree with * the same prefix as the filename we're looking for */ if (git_vector_bsearch2(&homing, entries, &homing_search_cmp, &ksearch) < 0) return GIT_ENOTFOUND; /* We found a common prefix. Look forward as long as * there are entries that share the common prefix */ for (i = homing; i < entries->length; ++i) { entry = entries->contents[i]; if (homing_search_cmp(&ksearch, entry) < 0) break; if (entry->filename_len == filename_len && memcmp(filename, entry->filename, filename_len) == 0) { if (at_pos) *at_pos = i; return 0; } } /* If we haven't found our filename yet, look backwards * too as long as we have entries with the same prefix */ if (homing > 0) { i = homing - 1; do { entry = entries->contents[i]; if (homing_search_cmp(&ksearch, entry) > 0) break; if (entry->filename_len == filename_len && memcmp(filename, entry->filename, filename_len) == 0) { if (at_pos) *at_pos = i; return 0; } } while (i-- > 0); } /* The filename doesn't exist at all */ return GIT_ENOTFOUND; } void git_tree_entry_free(git_tree_entry *entry) { if (entry == NULL) return; git__free(entry); } git_tree_entry *git_tree_entry_dup(const git_tree_entry *entry) { size_t total_size; git_tree_entry *copy; assert(entry); total_size = sizeof(git_tree_entry) + entry->filename_len + 1; copy = git__malloc(total_size); if (!copy) return NULL; memcpy(copy, entry, total_size); return copy; } void git_tree__free(git_tree *tree) { size_t i; git_tree_entry *e; git_vector_foreach(&tree->entries, i, e) git_tree_entry_free(e); git_vector_free(&tree->entries); git__free(tree); } const git_oid *git_tree_id(const git_tree *t) { return git_object_id((const git_object *)t); } git_repository *git_tree_owner(const git_tree *t) { return git_object_owner((const git_object *)t); } git_filemode_t git_tree_entry_filemode(const git_tree_entry *entry) { return (git_filemode_t)entry->attr; } const char *git_tree_entry_name(const git_tree_entry *entry) { assert(entry); return entry->filename; } const git_oid *git_tree_entry_id(const git_tree_entry *entry) { assert(entry); return &entry->oid; } git_otype git_tree_entry_type(const git_tree_entry *entry) { assert(entry); if (S_ISGITLINK(entry->attr)) return GIT_OBJ_COMMIT; else if (S_ISDIR(entry->attr)) return GIT_OBJ_TREE; else return GIT_OBJ_BLOB; } int git_tree_entry_to_object( git_object **object_out, git_repository *repo, const git_tree_entry *entry) { assert(entry && object_out); return git_object_lookup(object_out, repo, &entry->oid, GIT_OBJ_ANY); } static const git_tree_entry *entry_fromname( git_tree *tree, const char *name, size_t name_len) { size_t idx; if (tree_key_search(&idx, &tree->entries, name, name_len) < 0) return NULL; return git_vector_get(&tree->entries, idx); } const git_tree_entry *git_tree_entry_byname( git_tree *tree, const char *filename) { assert(tree && filename); return entry_fromname(tree, filename, strlen(filename)); } const git_tree_entry *git_tree_entry_byindex( git_tree *tree, size_t idx) { assert(tree); return git_vector_get(&tree->entries, idx); } const git_tree_entry *git_tree_entry_byoid( const git_tree *tree, const git_oid *oid) { size_t i; const git_tree_entry *e; assert(tree); git_vector_foreach(&tree->entries, i, e) { if (memcmp(&e->oid.id, &oid->id, sizeof(oid->id)) == 0) return e; } return NULL; } int git_tree__prefix_position(git_tree *tree, const char *path) { git_vector *entries = &tree->entries; struct tree_key_search ksearch; size_t at_pos; if (!path) return 0; ksearch.filename = path; ksearch.filename_len = strlen(path); /* Find tree entry with appropriate prefix */ git_vector_bsearch2(&at_pos, entries, &homing_search_cmp, &ksearch); for (; at_pos < entries->length; ++at_pos) { const git_tree_entry *entry = entries->contents[at_pos]; if (homing_search_cmp(&ksearch, entry) < 0) break; } for (; at_pos > 0; --at_pos) { const git_tree_entry *entry = entries->contents[at_pos - 1]; if (homing_search_cmp(&ksearch, entry) > 0) break; } return (int)at_pos; } size_t git_tree_entrycount(const git_tree *tree) { assert(tree); return tree->entries.length; } unsigned int git_treebuilder_entrycount(git_treebuilder *bld) { assert(bld); return (unsigned int)bld->entrycount; } static int tree_error(const char *str, const char *path) { if (path) giterr_set(GITERR_TREE, "%s - %s", str, path); else giterr_set(GITERR_TREE, "%s", str); return -1; } static int tree_parse_buffer(git_tree *tree, const char *buffer, const char *buffer_end) { if (git_vector_init(&tree->entries, DEFAULT_TREE_SIZE, entry_sort_cmp) < 0) return -1; while (buffer < buffer_end) { git_tree_entry *entry; int attr; if (git__strtol32(&attr, buffer, &buffer, 8) < 0 || !buffer) return tree_error("Failed to parse tree. Can't parse filemode", NULL); attr = normalize_filemode(attr); /* make sure to normalize the filemode */ if (*buffer++ != ' ') return tree_error("Failed to parse tree. Object is corrupted", NULL); if (memchr(buffer, 0, buffer_end - buffer) == NULL) return tree_error("Failed to parse tree. Object is corrupted", NULL); /** Allocate the entry and store it in the entries vector */ { entry = alloc_entry(buffer); GITERR_CHECK_ALLOC(entry); if (git_vector_insert(&tree->entries, entry) < 0) { git__free(entry); return -1; } entry->attr = attr; } while (buffer < buffer_end && *buffer != 0) buffer++; buffer++; git_oid_fromraw(&entry->oid, (const unsigned char *)buffer); buffer += GIT_OID_RAWSZ; } return 0; } int git_tree__parse(git_tree *tree, git_odb_object *obj) { assert(tree); return tree_parse_buffer(tree, (char *)obj->raw.data, (char *)obj->raw.data + obj->raw.len); } static size_t find_next_dir(const char *dirname, git_index *index, size_t start) { size_t dirlen, i, entries = git_index_entrycount(index); dirlen = strlen(dirname); for (i = start; i < entries; ++i) { const git_index_entry *entry = git_index_get_byindex(index, i); if (strlen(entry->path) < dirlen || memcmp(entry->path, dirname, dirlen) || (dirlen > 0 && entry->path[dirlen] != '/')) { break; } } return i; } static int append_entry( git_treebuilder *bld, const char *filename, const git_oid *id, git_filemode_t filemode) { git_tree_entry *entry; if (!valid_entry_name(filename)) return tree_error("Failed to insert entry. Invalid name for a tree entry", filename); entry = alloc_entry(filename); GITERR_CHECK_ALLOC(entry); git_oid_cpy(&entry->oid, id); entry->attr = (uint16_t)filemode; if (git_vector_insert(&bld->entries, entry) < 0) { git__free(entry); return -1; } bld->entrycount++; return 0; } static int write_tree( git_oid *oid, git_repository *repo, git_index *index, const char *dirname, size_t start) { git_treebuilder *bld = NULL; size_t i, entries = git_index_entrycount(index); int error; size_t dirname_len = strlen(dirname); const git_tree_cache *cache; cache = git_tree_cache_get(index->tree, dirname); if (cache != NULL && cache->entries >= 0){ git_oid_cpy(oid, &cache->oid); return (int)find_next_dir(dirname, index, start); } if ((error = git_treebuilder_create(&bld, NULL)) < 0 || bld == NULL) return -1; /* * This loop is unfortunate, but necessary. The index doesn't have * any directores, so we need to handle that manually, and we * need to keep track of the current position. */ for (i = start; i < entries; ++i) { const git_index_entry *entry = git_index_get_byindex(index, i); const char *filename, *next_slash; /* * If we've left our (sub)tree, exit the loop and return. The * first check is an early out (and security for the * third). The second check is a simple prefix comparison. The * third check catches situations where there is a directory * win32/sys and a file win32mmap.c. Without it, the following * code believes there is a file win32/mmap.c */ if (strlen(entry->path) < dirname_len || memcmp(entry->path, dirname, dirname_len) || (dirname_len > 0 && entry->path[dirname_len] != '/')) { break; } filename = entry->path + dirname_len; if (*filename == '/') filename++; next_slash = strchr(filename, '/'); if (next_slash) { git_oid sub_oid; int written; char *subdir, *last_comp; subdir = git__strndup(entry->path, next_slash - entry->path); GITERR_CHECK_ALLOC(subdir); /* Write out the subtree */ written = write_tree(&sub_oid, repo, index, subdir, i); if (written < 0) { tree_error("Failed to write subtree", subdir); git__free(subdir); goto on_error; } else { i = written - 1; /* -1 because of the loop increment */ } /* * We need to figure out what we want toinsert * into this tree. If we're traversing * deps/zlib/, then we only want to write * 'zlib' into the tree. */ last_comp = strrchr(subdir, '/'); if (last_comp) { last_comp++; /* Get rid of the '/' */ } else { last_comp = subdir; } error = append_entry(bld, last_comp, &sub_oid, S_IFDIR); git__free(subdir); if (error < 0) goto on_error; } else { error = append_entry(bld, filename, &entry->oid, entry->mode); if (error < 0) goto on_error; } } if (git_treebuilder_write(oid, repo, bld) < 0) goto on_error; git_treebuilder_free(bld); return (int)i; on_error: git_treebuilder_free(bld); return -1; } int git_tree__write_index( git_oid *oid, git_index *index, git_repository *repo) { int ret; bool old_ignore_case = false; assert(oid && index && repo); if (git_index_has_conflicts(index)) { giterr_set(GITERR_INDEX, "Cannot create a tree from a not fully merged index."); return GIT_EUNMERGED; } if (index->tree != NULL && index->tree->entries >= 0) { git_oid_cpy(oid, &index->tree->oid); return 0; } /* The tree cache didn't help us; we'll have to write * out a tree. If the index is ignore_case, we must * make it case-sensitive for the duration of the tree-write * operation. */ if (index->ignore_case) { old_ignore_case = true; git_index__set_ignore_case(index, false); } ret = write_tree(oid, repo, index, "", 0); if (old_ignore_case) git_index__set_ignore_case(index, true); return ret < 0 ? ret : 0; } int git_treebuilder_create(git_treebuilder **builder_p, const git_tree *source) { git_treebuilder *bld; size_t i, source_entries = DEFAULT_TREE_SIZE; assert(builder_p); bld = git__calloc(1, sizeof(git_treebuilder)); GITERR_CHECK_ALLOC(bld); if (source != NULL) source_entries = source->entries.length; if (git_vector_init(&bld->entries, source_entries, entry_sort_cmp) < 0) goto on_error; if (source != NULL) { git_tree_entry *entry_src; git_vector_foreach(&source->entries, i, entry_src) { if (append_entry( bld, entry_src->filename, &entry_src->oid, entry_src->attr) < 0) goto on_error; } } *builder_p = bld; return 0; on_error: git_treebuilder_free(bld); return -1; } int git_treebuilder_insert( const git_tree_entry **entry_out, git_treebuilder *bld, const char *filename, const git_oid *id, git_filemode_t filemode) { git_tree_entry *entry; size_t pos; assert(bld && id && filename); if (!valid_filemode(filemode)) return tree_error("Failed to insert entry. Invalid filemode for file", filename); if (!valid_entry_name(filename)) return tree_error("Failed to insert entry. Invalid name for a tree entry", filename); if (!tree_key_search(&pos, &bld->entries, filename, strlen(filename))) { entry = git_vector_get(&bld->entries, pos); if (entry->removed) { entry->removed = 0; bld->entrycount++; } } else { entry = alloc_entry(filename); GITERR_CHECK_ALLOC(entry); if (git_vector_insert(&bld->entries, entry) < 0) { git__free(entry); return -1; } bld->entrycount++; } git_oid_cpy(&entry->oid, id); entry->attr = filemode; if (entry_out) *entry_out = entry; return 0; } static git_tree_entry *treebuilder_get(git_treebuilder *bld, const char *filename) { size_t idx; git_tree_entry *entry; assert(bld && filename); if (tree_key_search(&idx, &bld->entries, filename, strlen(filename)) < 0) return NULL; entry = git_vector_get(&bld->entries, idx); if (entry->removed) return NULL; return entry; } const git_tree_entry *git_treebuilder_get(git_treebuilder *bld, const char *filename) { return treebuilder_get(bld, filename); } int git_treebuilder_remove(git_treebuilder *bld, const char *filename) { git_tree_entry *remove_ptr = treebuilder_get(bld, filename); if (remove_ptr == NULL || remove_ptr->removed) return tree_error("Failed to remove entry. File isn't in the tree", filename); remove_ptr->removed = 1; bld->entrycount--; return 0; } int git_treebuilder_write(git_oid *oid, git_repository *repo, git_treebuilder *bld) { int error = 0; size_t i; git_buf tree = GIT_BUF_INIT; git_odb *odb; assert(bld); git_vector_sort(&bld->entries); /* Grow the buffer beforehand to an estimated size */ error = git_buf_grow(&tree, bld->entries.length * 72); for (i = 0; i < bld->entries.length && !error; ++i) { git_tree_entry *entry = git_vector_get(&bld->entries, i); if (entry->removed) continue; git_buf_printf(&tree, "%o ", entry->attr); git_buf_put(&tree, entry->filename, entry->filename_len + 1); git_buf_put(&tree, (char *)entry->oid.id, GIT_OID_RAWSZ); if (git_buf_oom(&tree)) error = -1; } if (!error && !(error = git_repository_odb__weakptr(&odb, repo))) error = git_odb_write(oid, odb, tree.ptr, tree.size, GIT_OBJ_TREE); git_buf_free(&tree); return error; } void git_treebuilder_filter( git_treebuilder *bld, git_treebuilder_filter_cb filter, void *payload) { size_t i; git_tree_entry *entry; assert(bld && filter); git_vector_foreach(&bld->entries, i, entry) { if (!entry->removed && filter(entry, payload)) { entry->removed = 1; bld->entrycount--; } } } void git_treebuilder_clear(git_treebuilder *bld) { size_t i; git_tree_entry *e; assert(bld); git_vector_foreach(&bld->entries, i, e) git_tree_entry_free(e); git_vector_clear(&bld->entries); bld->entrycount = 0; } void git_treebuilder_free(git_treebuilder *bld) { if (bld == NULL) return; git_treebuilder_clear(bld); git_vector_free(&bld->entries); git__free(bld); } static size_t subpath_len(const char *path) { const char *slash_pos = strchr(path, '/'); if (slash_pos == NULL) return strlen(path); return slash_pos - path; } int git_tree_entry_bypath( git_tree_entry **entry_out, git_tree *root, const char *path) { int error = 0; git_tree *subtree; const git_tree_entry *entry; size_t filename_len; /* Find how long is the current path component (i.e. * the filename between two slashes */ filename_len = subpath_len(path); if (filename_len == 0) { giterr_set(GITERR_TREE, "Invalid tree path given"); return GIT_ENOTFOUND; } entry = entry_fromname(root, path, filename_len); if (entry == NULL) { giterr_set(GITERR_TREE, "The path '%s' does not exist in the given tree", path); return GIT_ENOTFOUND; } switch (path[filename_len]) { case '/': /* If there are more components in the path... * then this entry *must* be a tree */ if (!git_tree_entry__is_tree(entry)) { giterr_set(GITERR_TREE, "The path '%s' does not exist in the given tree", path); return GIT_ENOTFOUND; } /* If there's only a slash left in the path, we * return the current entry; otherwise, we keep * walking down the path */ if (path[filename_len + 1] != '\0') break; case '\0': /* If there are no more components in the path, return * this entry */ *entry_out = git_tree_entry_dup(entry); return 0; } if (git_tree_lookup(&subtree, root->object.repo, &entry->oid) < 0) return -1; error = git_tree_entry_bypath( entry_out, subtree, path + filename_len + 1 ); git_tree_free(subtree); return error; } static int tree_walk( const git_tree *tree, git_treewalk_cb callback, git_buf *path, void *payload, bool preorder) { int error = 0; size_t i; const git_tree_entry *entry; git_vector_foreach(&tree->entries, i, entry) { if (preorder) { error = callback(path->ptr, entry, payload); if (error > 0) continue; if (error < 0) { giterr_clear(); return GIT_EUSER; } } if (git_tree_entry__is_tree(entry)) { git_tree *subtree; size_t path_len = git_buf_len(path); if ((error = git_tree_lookup( &subtree, tree->object.repo, &entry->oid)) < 0) break; /* append the next entry to the path */ git_buf_puts(path, entry->filename); git_buf_putc(path, '/'); if (git_buf_oom(path)) return -1; error = tree_walk(subtree, callback, path, payload, preorder); if (error != 0) break; git_buf_truncate(path, path_len); git_tree_free(subtree); } if (!preorder && callback(path->ptr, entry, payload) < 0) { giterr_clear(); error = GIT_EUSER; break; } } return error; } int git_tree_walk( const git_tree *tree, git_treewalk_mode mode, git_treewalk_cb callback, void *payload) { int error = 0; git_buf root_path = GIT_BUF_INIT; if (mode != GIT_TREEWALK_POST && mode != GIT_TREEWALK_PRE) { giterr_set(GITERR_INVALID, "Invalid walking mode for tree walk"); return -1; } error = tree_walk( tree, callback, &root_path, payload, (mode == GIT_TREEWALK_PRE)); git_buf_free(&root_path); return error; }