Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "tag.h"
   3#include "commit.h"
   4#include "tree.h"
   5#include "blob.h"
   6
   7const char *tag_type = "tag";
   8
   9struct object *deref_tag(struct object *o, const char *warn, int warnlen)
  10{
  11        while (o && o->type == OBJ_TAG)
  12                if (((struct tag *)o)->tagged)
  13                        o = parse_object(((struct tag *)o)->tagged->sha1);
  14                else
  15                        o = NULL;
  16        if (!o && warn) {
  17                if (!warnlen)
  18                        warnlen = strlen(warn);
  19                error("missing object referenced by '%.*s'", warnlen, warn);
  20        }
  21        return o;
  22}
  23
  24struct tag *lookup_tag(const unsigned char *sha1)
  25{
  26        struct object *obj = lookup_object(sha1);
  27        if (!obj)
  28                return create_object(sha1, OBJ_TAG, alloc_tag_node());
  29        if (!obj->type)
  30                obj->type = OBJ_TAG;
  31        if (obj->type != OBJ_TAG) {
  32                error("Object %s is a %s, not a tag",
  33                      sha1_to_hex(sha1), typename(obj->type));
  34                return NULL;
  35        }
  36        return (struct tag *) obj;
  37}
  38
  39int parse_tag_buffer(struct tag *item, void *data, unsigned long size)
  40{
  41        int typelen, taglen;
  42        unsigned char sha1[20];
  43        const char *type_line, *tag_line, *sig_line;
  44        char type[20];
  45        const char *start = data;
  46
  47        if (item->object.parsed)
  48                return 0;
  49        item->object.parsed = 1;
  50
  51        if (size < 64)
  52                return -1;
  53        if (memcmp("object ", data, 7) || get_sha1_hex((char *) data + 7, sha1))
  54                return -1;
  55
  56        type_line = (char *) data + 48;
  57        if (memcmp("\ntype ", type_line-1, 6))
  58                return -1;
  59
  60        tag_line = memchr(type_line, '\n', size - (type_line - start));
  61        if (!tag_line || memcmp("tag ", ++tag_line, 4))
  62                return -1;
  63
  64        sig_line = memchr(tag_line, '\n', size - (tag_line - start));
  65        if (!sig_line)
  66                return -1;
  67        sig_line++;
  68
  69        typelen = tag_line - type_line - strlen("type \n");
  70        if (typelen >= 20)
  71                return -1;
  72        memcpy(type, type_line + 5, typelen);
  73        type[typelen] = '\0';
  74        taglen = sig_line - tag_line - strlen("tag \n");
  75        item->tag = xmemdupz(tag_line + 4, taglen);
  76
  77        if (!strcmp(type, blob_type)) {
  78                item->tagged = &lookup_blob(sha1)->object;
  79        } else if (!strcmp(type, tree_type)) {
  80                item->tagged = &lookup_tree(sha1)->object;
  81        } else if (!strcmp(type, commit_type)) {
  82                item->tagged = &lookup_commit(sha1)->object;
  83        } else if (!strcmp(type, tag_type)) {
  84                item->tagged = &lookup_tag(sha1)->object;
  85        } else {
  86                error("Unknown type %s", type);
  87                item->tagged = NULL;
  88        }
  89
  90        return 0;
  91}
  92
  93int parse_tag(struct tag *item)
  94{
  95        enum object_type type;
  96        void *data;
  97        unsigned long size;
  98        int ret;
  99
 100        if (item->object.parsed)
 101                return 0;
 102        data = read_sha1_file(item->object.sha1, &type, &size);
 103        if (!data)
 104                return error("Could not read %s",
 105                             sha1_to_hex(item->object.sha1));
 106        if (type != OBJ_TAG) {
 107                free(data);
 108                return error("Object %s not a tag",
 109                             sha1_to_hex(item->object.sha1));
 110        }
 111        ret = parse_tag_buffer(item, data, size);
 112        free(data);
 113        return ret;
 114}