MinGW: 64-bit file offsets
[git/platforms.git] / tag.c
blob4470d2bf78e1fbb00d00e487f41daa4373cf48e1
1 #include "cache.h"
2 #include "tag.h"
3 #include "commit.h"
4 #include "tree.h"
5 #include "blob.h"
7 const char *tag_type = "tag";
9 struct object *deref_tag(struct object *o, const char *warn, int warnlen)
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);
21 return o;
24 struct tag *lookup_tag(const unsigned char *sha1)
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;
36 return (struct tag *) obj;
39 int parse_tag_buffer(struct tag *item, void *data, unsigned long size)
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;
47 if (item->object.parsed)
48 return 0;
49 item->object.parsed = 1;
51 if (size < 64)
52 return -1;
53 if (memcmp("object ", data, 7) || get_sha1_hex((char *) data + 7, sha1))
54 return -1;
56 type_line = (char *) data + 48;
57 if (memcmp("\ntype ", type_line-1, 6))
58 return -1;
60 tag_line = memchr(type_line, '\n', size - (type_line - start));
61 if (!tag_line || memcmp("tag ", ++tag_line, 4))
62 return -1;
64 sig_line = memchr(tag_line, '\n', size - (tag_line - start));
65 if (!sig_line)
66 return -1;
67 sig_line++;
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);
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;
90 return 0;
93 int parse_tag(struct tag *item)
95 enum object_type type;
96 void *data;
97 unsigned long size;
98 int ret;
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));
111 ret = parse_tag_buffer(item, data, size);
112 free(data);
113 return ret;