1#include "cache.h"2#include "tag.h"3#include "commit.h"4#include "tree.h"5#include "blob.h"67const char *tag_type = "tag";89struct object *deref_tag(struct object *o, const char *warn, int warnlen)10{11while (o && o->type == OBJ_TAG)12if (((struct tag *)o)->tagged)13o = parse_object(((struct tag *)o)->tagged->sha1);14else15o = NULL;16if (!o && warn) {17if (!warnlen)18warnlen = strlen(warn);19error("missing object referenced by '%.*s'", warnlen, warn);20}21return o;22}2324struct tag *lookup_tag(const unsigned char *sha1)25{26struct object *obj = lookup_object(sha1);27if (!obj)28return create_object(sha1, OBJ_TAG, alloc_tag_node());29if (!obj->type)30obj->type = OBJ_TAG;31if (obj->type != OBJ_TAG) {32error("Object %s is a %s, not a tag",33sha1_to_hex(sha1), typename(obj->type));34return NULL;35}36return (struct tag *) obj;37}3839static unsigned long parse_tag_date(const char *buf, const char *tail)40{41const char *dateptr;4243while (buf < tail && *buf++ != '>')44/* nada */;45if (buf >= tail)46return 0;47dateptr = buf;48while (buf < tail && *buf++ != '\n')49/* nada */;50if (buf >= tail)51return 0;52/* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */53return strtoul(dateptr, NULL, 10);54}5556int parse_tag_buffer(struct tag *item, void *data, unsigned long size)57{58unsigned char sha1[20];59char type[20];60const char *bufptr = data;61const char *tail = bufptr + size;62const char *nl;6364if (item->object.parsed)65return 0;66item->object.parsed = 1;6768if (size < 64)69return -1;70if (memcmp("object ", bufptr, 7) || get_sha1_hex(bufptr + 7, sha1) || bufptr[47] != '\n')71return -1;72bufptr += 48; /* "object " + sha1 + "\n" */7374if (prefixcmp(bufptr, "type "))75return -1;76bufptr += 5;77nl = memchr(bufptr, '\n', tail - bufptr);78if (!nl || sizeof(type) <= (nl - bufptr))79return -1;80strncpy(type, bufptr, nl - bufptr);81type[nl - bufptr] = '\0';82bufptr = nl + 1;8384if (!strcmp(type, blob_type)) {85item->tagged = &lookup_blob(sha1)->object;86} else if (!strcmp(type, tree_type)) {87item->tagged = &lookup_tree(sha1)->object;88} else if (!strcmp(type, commit_type)) {89item->tagged = &lookup_commit(sha1)->object;90} else if (!strcmp(type, tag_type)) {91item->tagged = &lookup_tag(sha1)->object;92} else {93error("Unknown type %s", type);94item->tagged = NULL;95}9697if (prefixcmp(bufptr, "tag "))98return -1;99bufptr += 4;100nl = memchr(bufptr, '\n', tail - bufptr);101if (!nl)102return -1;103item->tag = xmemdupz(bufptr, nl - bufptr);104bufptr = nl + 1;105106if (!prefixcmp(bufptr, "tagger "))107item->date = parse_tag_date(bufptr, tail);108else109item->date = 0;110111return 0;112}113114int parse_tag(struct tag *item)115{116enum object_type type;117void *data;118unsigned long size;119int ret;120121if (item->object.parsed)122return 0;123data = read_sha1_file(item->object.sha1, &type, &size);124if (!data)125return error("Could not read %s",126sha1_to_hex(item->object.sha1));127if (type != OBJ_TAG) {128free(data);129return error("Object %s not a tag",130sha1_to_hex(item->object.sha1));131}132ret = parse_tag_buffer(item, data, size);133free(data);134return ret;135}