406dba2aa5607332fe022fcba1beb045fa61c5f4
   1#include "tag.h"
   2#include "cache.h"
   3
   4const char *tag_type = "tag";
   5
   6struct tag *lookup_tag(unsigned char *sha1)
   7{
   8        struct object *obj = lookup_object(sha1);
   9        if (!obj) {
  10                struct tag *ret = xmalloc(sizeof(struct tag));
  11                memset(ret, 0, sizeof(struct tag));
  12                created_object(sha1, &ret->object);
  13                ret->object.type = tag_type;
  14                return ret;
  15        }
  16        if (obj->type != tag_type) {
  17                error("Object %s is a %s, not a tree", 
  18                      sha1_to_hex(sha1), obj->type);
  19                return NULL;
  20        }
  21        return (struct tag *) obj;
  22}
  23
  24int parse_tag(struct tag *item)
  25{
  26        char type[20];
  27        void *data, *bufptr;
  28        unsigned long size;
  29        int typelen, taglen;
  30        unsigned char object[20];
  31        const char *type_line, *tag_line, *sig_line;
  32
  33        if (item->object.parsed)
  34                return 0;
  35        item->object.parsed = 1;
  36        data = bufptr = read_sha1_file(item->object.sha1, type, &size);
  37        if (!data)
  38                return error("Could not read %s",
  39                             sha1_to_hex(item->object.sha1));
  40        if (strcmp(type, tag_type))
  41                return error("Object %s not a tag",
  42                             sha1_to_hex(item->object.sha1));
  43
  44        if (size < 64)
  45                return -1;
  46        if (memcmp("object ", data, 7) || get_sha1_hex(data + 7, object))
  47                return -1;
  48
  49        item->tagged = parse_object(object);
  50
  51        type_line = data + 48;
  52        if (memcmp("\ntype ", type_line-1, 6))
  53                return -1;
  54
  55        tag_line = strchr(type_line, '\n');
  56        if (!tag_line || memcmp("tag ", ++tag_line, 4))
  57                return -1;
  58
  59        sig_line = strchr(tag_line, '\n');
  60        if (!sig_line)
  61                return -1;
  62        sig_line++;
  63
  64        typelen = tag_line - type_line - strlen("type \n");
  65        if (typelen >= 20)
  66                return -1;
  67        taglen = sig_line - tag_line - strlen("tag \n");
  68        item->tag = xmalloc(taglen + 1);
  69        memcpy(item->tag, tag_line + 4, taglen);
  70        item->tag[taglen] = '\0';
  71
  72        return 0;
  73}