tag.con commit Documentation: add git-mergetool to the command list. (86952cd)
   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                o = parse_object(((struct tag *)o)->tagged->sha1);
  13        if (!o && warn) {
  14                if (!warnlen)
  15                        warnlen = strlen(warn);
  16                error("missing object referenced by '%.*s'", warnlen, warn);
  17        }
  18        return o;
  19}
  20
  21struct tag *lookup_tag(const unsigned char *sha1)
  22{
  23        struct object *obj = lookup_object(sha1);
  24        if (!obj) {
  25                struct tag *ret = alloc_tag_node();
  26                created_object(sha1, &ret->object);
  27                ret->object.type = OBJ_TAG;
  28                return ret;
  29        }
  30        if (!obj->type)
  31                obj->type = OBJ_TAG;
  32        if (obj->type != OBJ_TAG) {
  33                error("Object %s is a %s, not a tree",
  34                      sha1_to_hex(sha1), typename(obj->type));
  35                return NULL;
  36        }
  37        return (struct tag *) obj;
  38}
  39
  40int parse_tag_buffer(struct tag *item, void *data, unsigned long size)
  41{
  42        int typelen, taglen;
  43        unsigned char sha1[20];
  44        const char *type_line, *tag_line, *sig_line;
  45        char type[20];
  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 = strchr(type_line, '\n');
  61        if (!tag_line || memcmp("tag ", ++tag_line, 4))
  62                return -1;
  63
  64        sig_line = strchr(tag_line, '\n');
  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 = xmalloc(taglen + 1);
  76        memcpy(item->tag, tag_line + 4, taglen);
  77        item->tag[taglen] = '\0';
  78
  79        if (!strcmp(type, blob_type)) {
  80                item->tagged = &lookup_blob(sha1)->object;
  81        } else if (!strcmp(type, tree_type)) {
  82                item->tagged = &lookup_tree(sha1)->object;
  83        } else if (!strcmp(type, commit_type)) {
  84                item->tagged = &lookup_commit(sha1)->object;
  85        } else if (!strcmp(type, tag_type)) {
  86                item->tagged = &lookup_tag(sha1)->object;
  87        } else {
  88                error("Unknown type %s", type);
  89                item->tagged = NULL;
  90        }
  91
  92        if (item->tagged && track_object_refs) {
  93                struct object_refs *refs = alloc_object_refs(1);
  94                refs->ref[0] = item->tagged;
  95                set_object_refs(&item->object, refs);
  96        }
  97
  98        return 0;
  99}
 100
 101int parse_tag(struct tag *item)
 102{
 103        enum object_type type;
 104        void *data;
 105        unsigned long size;
 106        int ret;
 107
 108        if (item->object.parsed)
 109                return 0;
 110        data = read_sha1_file(item->object.sha1, &type, &size);
 111        if (!data)
 112                return error("Could not read %s",
 113                             sha1_to_hex(item->object.sha1));
 114        if (type != OBJ_TAG) {
 115                free(data);
 116                return error("Object %s not a tag",
 117                             sha1_to_hex(item->object.sha1));
 118        }
 119        ret = parse_tag_buffer(item, data, size);
 120        free(data);
 121        return ret;
 122}