| /* |
| * 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 "tree-cache.h" |
| |
| static git_tree_cache *find_child( |
| const git_tree_cache *tree, const char *path, const char *end) |
| { |
| size_t i, dirlen = end ? (size_t)(end - path) : strlen(path); |
| |
| for (i = 0; i < tree->children_count; ++i) { |
| git_tree_cache *child = tree->children[i]; |
| |
| if (child->namelen == dirlen && !memcmp(path, child->name, dirlen)) |
| return child; |
| } |
| |
| return NULL; |
| } |
| |
| void git_tree_cache_invalidate_path(git_tree_cache *tree, const char *path) |
| { |
| const char *ptr = path, *end; |
| |
| if (tree == NULL) |
| return; |
| |
| tree->entries = -1; |
| |
| while (ptr != NULL) { |
| end = strchr(ptr, '/'); |
| |
| if (end == NULL) /* End of path */ |
| break; |
| |
| tree = find_child(tree, ptr, end); |
| if (tree == NULL) /* We don't have that tree */ |
| return; |
| |
| tree->entries = -1; |
| ptr = end + 1; |
| } |
| } |
| |
| const git_tree_cache *git_tree_cache_get(const git_tree_cache *tree, const char *path) |
| { |
| const char *ptr = path, *end; |
| |
| if (tree == NULL) { |
| return NULL; |
| } |
| |
| while (1) { |
| end = strchr(ptr, '/'); |
| |
| tree = find_child(tree, ptr, end); |
| if (tree == NULL) /* Can't find it */ |
| return NULL; |
| |
| if (end == NULL || *end + 1 == '\0') |
| return tree; |
| |
| ptr = end + 1; |
| } |
| } |
| |
| static int read_tree_internal(git_tree_cache **out, |
| const char **buffer_in, const char *buffer_end, git_tree_cache *parent) |
| { |
| git_tree_cache *tree = NULL; |
| const char *name_start, *buffer; |
| int count; |
| size_t name_len; |
| |
| buffer = name_start = *buffer_in; |
| |
| if ((buffer = memchr(buffer, '\0', buffer_end - buffer)) == NULL) |
| goto corrupted; |
| |
| if (++buffer >= buffer_end) |
| goto corrupted; |
| |
| name_len = strlen(name_start); |
| tree = git__malloc(sizeof(git_tree_cache) + name_len + 1); |
| GITERR_CHECK_ALLOC(tree); |
| |
| memset(tree, 0x0, sizeof(git_tree_cache)); |
| tree->parent = parent; |
| |
| /* NUL-terminated tree name */ |
| tree->namelen = name_len; |
| memcpy(tree->name, name_start, name_len); |
| tree->name[name_len] = '\0'; |
| |
| /* Blank-terminated ASCII decimal number of entries in this tree */ |
| if (git__strtol32(&count, buffer, &buffer, 10) < 0) |
| goto corrupted; |
| |
| tree->entries = count; |
| |
| if (*buffer != ' ' || ++buffer >= buffer_end) |
| goto corrupted; |
| |
| /* Number of children of the tree, newline-terminated */ |
| if (git__strtol32(&count, buffer, &buffer, 10) < 0 || count < 0) |
| goto corrupted; |
| |
| tree->children_count = count; |
| |
| if (*buffer != '\n' || ++buffer > buffer_end) |
| goto corrupted; |
| |
| /* The SHA1 is only there if it's not invalidated */ |
| if (tree->entries >= 0) { |
| /* 160-bit SHA-1 for this tree and it's children */ |
| if (buffer + GIT_OID_RAWSZ > buffer_end) |
| goto corrupted; |
| |
| git_oid_fromraw(&tree->oid, (const unsigned char *)buffer); |
| buffer += GIT_OID_RAWSZ; |
| } |
| |
| /* Parse children: */ |
| if (tree->children_count > 0) { |
| unsigned int i; |
| |
| tree->children = git__malloc(tree->children_count * sizeof(git_tree_cache *)); |
| GITERR_CHECK_ALLOC(tree->children); |
| |
| memset(tree->children, 0x0, tree->children_count * sizeof(git_tree_cache *)); |
| |
| for (i = 0; i < tree->children_count; ++i) { |
| if (read_tree_internal(&tree->children[i], &buffer, buffer_end, tree) < 0) |
| goto corrupted; |
| } |
| } |
| |
| *buffer_in = buffer; |
| *out = tree; |
| return 0; |
| |
| corrupted: |
| git_tree_cache_free(tree); |
| giterr_set(GITERR_INDEX, "Corrupted TREE extension in index"); |
| return -1; |
| } |
| |
| int git_tree_cache_read(git_tree_cache **tree, const char *buffer, size_t buffer_size) |
| { |
| const char *buffer_end = buffer + buffer_size; |
| |
| if (read_tree_internal(tree, &buffer, buffer_end, NULL) < 0) |
| return -1; |
| |
| if (buffer < buffer_end) { |
| giterr_set(GITERR_INDEX, "Corrupted TREE extension in index (unexpected trailing data)"); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| void git_tree_cache_free(git_tree_cache *tree) |
| { |
| unsigned int i; |
| |
| if (tree == NULL) |
| return; |
| |
| if (tree->children != NULL) { |
| for (i = 0; i < tree->children_count; ++i) |
| git_tree_cache_free(tree->children[i]); |
| |
| git__free(tree->children); |
| } |
| |
| git__free(tree); |
| } |