diff options
Diffstat (limited to 'notes.c')
| -rw-r--r-- | notes.c | 143 |
1 files changed, 71 insertions, 72 deletions
@@ -64,7 +64,7 @@ struct non_note { #define CLR_PTR_TYPE(ptr) ((void *) ((uintptr_t) (ptr) & ~3)) #define SET_PTR_TYPE(ptr, type) ((void *) ((uintptr_t) (ptr) | (type))) -#define GET_NIBBLE(n, sha1) (((sha1[(n) >> 1]) >> ((~(n) & 0x01) << 2)) & 0x0f) +#define GET_NIBBLE(n, sha1) ((((sha1)[(n) >> 1]) >> ((~(n) & 0x01) << 2)) & 0x0f) #define KEY_INDEX (GIT_SHA1_RAWSZ - 1) #define FANOUT_PATH_SEPARATORS ((GIT_SHA1_HEXSZ / 2) - 1) @@ -335,31 +335,20 @@ static void note_tree_free(struct int_node *tree) } /* - * Convert a partial SHA1 hex string to the corresponding partial SHA1 value. - * - hex - Partial SHA1 segment in ASCII hex format - * - hex_len - Length of above segment. Must be multiple of 2 between 0 and 40 - * - sha1 - Partial SHA1 value is written here - * - sha1_len - Max #bytes to store in sha1, Must be >= hex_len / 2, and < 20 - * Returns -1 on error (invalid arguments or invalid SHA1 (not in hex format)). - * Otherwise, returns number of bytes written to sha1 (i.e. hex_len / 2). - * Pads sha1 with NULs up to sha1_len (not included in returned length). + * Read `len` pairs of hexadecimal digits from `hex` and write the + * values to `binary` as `len` bytes. Return 0 on success, or -1 if + * the input does not consist of hex digits). */ -static int get_oid_hex_segment(const char *hex, unsigned int hex_len, - unsigned char *oid, unsigned int oid_len) +static int hex_to_bytes(unsigned char *binary, const char *hex, size_t len) { - unsigned int i, len = hex_len >> 1; - if (hex_len % 2 != 0 || len > oid_len) - return -1; - for (i = 0; i < len; i++) { + for (; len; len--, hex += 2) { unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]); + if (val & ~0xff) return -1; - *oid++ = val; - hex += 2; + *binary++ = val; } - for (; i < oid_len; i++) - *oid++ = 0; - return len; + return 0; } static int non_note_cmp(const struct non_note *a, const struct non_note *b) @@ -417,80 +406,90 @@ static void load_subtree(struct notes_tree *t, struct leaf_node *subtree, struct int_node *node, unsigned int n) { struct object_id object_oid; - unsigned int prefix_len; + size_t prefix_len; void *buf; struct tree_desc desc; struct name_entry entry; - int len, path_len; - unsigned char type; - struct leaf_node *l; - buf = fill_tree_descriptor(&desc, subtree->val_oid.hash); + buf = fill_tree_descriptor(&desc, &subtree->val_oid); if (!buf) die("Could not read %s for notes-index", oid_to_hex(&subtree->val_oid)); prefix_len = subtree->key_oid.hash[KEY_INDEX]; - assert(prefix_len * 2 >= n); + if (prefix_len >= GIT_SHA1_RAWSZ) + BUG("prefix_len (%"PRIuMAX") is out of range", (uintmax_t)prefix_len); + if (prefix_len * 2 < n) + BUG("prefix_len (%"PRIuMAX") is too small", (uintmax_t)prefix_len); memcpy(object_oid.hash, subtree->key_oid.hash, prefix_len); while (tree_entry(&desc, &entry)) { - path_len = strlen(entry.path); - len = get_oid_hex_segment(entry.path, path_len, - object_oid.hash + prefix_len, GIT_SHA1_RAWSZ - prefix_len); - if (len < 0) - goto handle_non_note; /* entry.path is not a SHA1 */ - len += prefix_len; + unsigned char type; + struct leaf_node *l; + size_t path_len = strlen(entry.path); + + if (path_len == 2 * (GIT_SHA1_RAWSZ - prefix_len)) { + /* This is potentially the remainder of the SHA-1 */ + + if (!S_ISREG(entry.mode)) + /* notes must be blobs */ + goto handle_non_note; + + if (hex_to_bytes(object_oid.hash + prefix_len, entry.path, + GIT_SHA1_RAWSZ - prefix_len)) + goto handle_non_note; /* entry.path is not a SHA1 */ - /* - * If object SHA1 is complete (len == 20), assume note object - * If object SHA1 is incomplete (len < 20), and current - * component consists of 2 hex chars, assume note subtree - */ - if (len <= GIT_SHA1_RAWSZ) { type = PTR_TYPE_NOTE; - l = (struct leaf_node *) - xcalloc(1, sizeof(struct leaf_node)); - oidcpy(&l->key_oid, &object_oid); - oidcpy(&l->val_oid, entry.oid); - if (len < GIT_SHA1_RAWSZ) { - if (!S_ISDIR(entry.mode) || path_len != 2) - goto handle_non_note; /* not subtree */ - l->key_oid.hash[KEY_INDEX] = (unsigned char) len; - type = PTR_TYPE_SUBTREE; - } - if (note_tree_insert(t, node, n, l, type, - combine_notes_concatenate)) - die("Failed to load %s %s into notes tree " - "from %s", - type == PTR_TYPE_NOTE ? "note" : "subtree", - oid_to_hex(&l->key_oid), t->ref); + } else if (path_len == 2) { + /* This is potentially an internal node */ + size_t len = prefix_len; + + if (!S_ISDIR(entry.mode)) + /* internal nodes must be trees */ + goto handle_non_note; + + if (hex_to_bytes(object_oid.hash + len++, entry.path, 1)) + goto handle_non_note; /* entry.path is not a SHA1 */ + + /* + * Pad the rest of the SHA-1 with zeros, + * except for the last byte, where we write + * the length: + */ + memset(object_oid.hash + len, 0, GIT_SHA1_RAWSZ - len - 1); + object_oid.hash[KEY_INDEX] = (unsigned char)len; + + type = PTR_TYPE_SUBTREE; + } else { + /* This can't be part of a note */ + goto handle_non_note; } + + l = xcalloc(1, sizeof(*l)); + oidcpy(&l->key_oid, &object_oid); + oidcpy(&l->val_oid, entry.oid); + if (note_tree_insert(t, node, n, l, type, + combine_notes_concatenate)) + die("Failed to load %s %s into notes tree " + "from %s", + type == PTR_TYPE_NOTE ? "note" : "subtree", + oid_to_hex(&l->key_oid), t->ref); + continue; handle_non_note: /* - * Determine full path for this non-note entry: - * The filename is already found in entry.path, but the - * directory part of the path must be deduced from the subtree - * containing this entry. We assume here that the overall notes - * tree follows a strict byte-based progressive fanout - * structure (i.e. using 2/38, 2/2/36, etc. fanouts, and not - * e.g. 4/36 fanout). This means that if a non-note is found at - * path "dead/beef", the following code will register it as - * being found on "de/ad/beef". - * On the other hand, if you use such non-obvious non-note - * paths in the middle of a notes tree, you deserve what's - * coming to you ;). Note that for non-notes that are not - * SHA1-like at the top level, there will be no problems. - * - * To conclude, it is strongly advised to make sure non-notes - * have at least one non-hex character in the top-level path - * component. + * Determine full path for this non-note entry. The + * filename is already found in entry.path, but the + * directory part of the path must be deduced from the + * subtree containing this entry based on our + * knowledge that the overall notes tree follows a + * strict byte-based progressive fanout structure + * (i.e. using 2/38, 2/2/36, etc. fanouts). */ { struct strbuf non_note_path = STRBUF_INIT; const char *q = oid_to_hex(&subtree->key_oid); - int i; + size_t i; for (i = 0; i < prefix_len; i++) { strbuf_addch(&non_note_path, *q++); strbuf_addch(&non_note_path, *q++); |