object.c

   1 #include "cache.h"
   2 #include "object.h"
   3 #include "blob.h"
   4 #include "tree.h"
   5 #include "commit.h"
   6 #include "tag.h"
   7
   8 static struct object **objs;
   9 static int nr_objs, obj_allocs;
  10
  11 unsigned int get_max_object_index(void)
  12 {
  13         return obj_allocs;
  14 }
  15
  16 struct object *get_indexed_object(unsigned int idx)
  17 {
  18         return objs[idx];
  19 }
  20
  21 const char *type_names[] = {
  22         "none", "blob", "tree", "commit", "bad"
  23 };
  24
  25 static int hashtable_index(const unsigned char *sha1)
  26 {
  27         unsigned int i;
  28         memcpy(&i, sha1, sizeof(unsigned int));
  29         return (int)(i % obj_allocs);
  30 }
  31
  32 static int find_object(const unsigned char *sha1)
  33 {
  34         int i;
  35
  36         if (!objs)
  37                 return -1;
  38
  39         i = hashtable_index(sha1);
  40         while (objs[i]) {
  41                 if (memcmp(sha1, objs[i]->sha1, 20) == 0)
  42                         return i;
  43                 i++;
  44                 if (i == obj_allocs)
  45                         i = 0;
  46         }
  47         return -1 - i;
  48 }
  49
  50 struct object *lookup_object(const unsigned char *sha1)
  51 {
  52         int pos = find_object(sha1);
  53         if (pos >= 0)
  54                 return objs[pos];
  55         return NULL;
  56 }
  57
  58 void created_object(const unsigned char *sha1, struct object *obj)
  59 {
  60         int pos;
  61
  62         obj->parsed = 0;
  63         memcpy(obj->sha1, sha1, 20);
  64         obj->type = TYPE_NONE;
  65         obj->used = 0;
  66
  67         if (obj_allocs - 1 <= nr_objs * 2) {
  68                 int i, count = obj_allocs;
  69                 obj_allocs = (obj_allocs < 32 ? 32 : 2 * obj_allocs);
  70                 objs = xrealloc(objs, obj_allocs * sizeof(struct object *));
  71                 memset(objs + count, 0, (obj_allocs - count)
  72                                 * sizeof(struct object *));
  73                 for (i = 0; i < obj_allocs; i++)
  74                         if (objs[i]) {
  75                                 int j = find_object(objs[i]->sha1);
  76                                 if (j != i) {
  77                                         j = -1 - j;
  78                                         objs[j] = objs[i];
  79                                         objs[i] = NULL;
  80                                 }
  81                         }
  82         }
  83
  84         pos = find_object(sha1);
  85         if (pos >= 0)
  86                 die("Inserting %s twice\n", sha1_to_hex(sha1));
  87         pos = -pos-1;
  88
  89         objs[pos] = obj;
  90         nr_objs++;
  91 }
  92
  93 struct object *lookup_object_type(const unsigned char *sha1, const char *type)
  94 {
  95         if (!type) {
  96                 return lookup_unknown_object(sha1);
  97         } else if (!strcmp(type, blob_type)) {
  98                 return &lookup_blob(sha1)->object;
  99         } else if (!strcmp(type, tree_type)) {
 100                 return &lookup_tree(sha1)->object;
 101         } else if (!strcmp(type, commit_type)) {
 102                 return &lookup_commit(sha1)->object;
 103         } else if (!strcmp(type, tag_type)) {
 104                 return &lookup_tag(sha1)->object;
 105         } else {
 106                 error("Unknown type %s", type);
 107                 return NULL;
 108         }
 109 }
 110
 111 union any_object {
 112         struct object object;
 113         struct commit commit;
 114         struct tree tree;
 115         struct blob blob;
 116         struct tag tag;
 117 };
 118
 119 struct object *lookup_unknown_object(const unsigned char *sha1)
 120 {
 121         struct object *obj = lookup_object(sha1);
 122         if (!obj) {
 123                 union any_object *ret = xcalloc(1, sizeof(*ret));
 124                 created_object(sha1, &ret->object);
 125                 ret->object.type = TYPE_NONE;
 126                 return &ret->object;
 127         }
 128         return obj;
 129 }
 130
 131 struct object *parse_object(const unsigned char *sha1)
 132 {
 133         unsigned long size;
 134         char type[20];
 135         void *buffer = read_sha1_file(sha1, type, &size);
 136         if (buffer) {
 137                 struct object *obj;
 138                 if (check_sha1_signature(sha1, buffer, size, type) < 0)
 139                         printf("sha1 mismatch %s\n", sha1_to_hex(sha1));
 140                 if (!strcmp(type, blob_type)) {
 141                         struct blob *blob = lookup_blob(sha1);
 142                         parse_blob_buffer(blob, buffer, size);
 143                         obj = &blob->object;
 144                 } else if (!strcmp(type, tree_type)) {
 145                         struct tree *tree = lookup_tree(sha1);
 146                         obj = &tree->object;
 147                         if (!tree->object.parsed) {
 148                                 parse_tree_buffer(tree, buffer, size);
 149                                 buffer = NULL;
 150                         }
 151                 } else if (!strcmp(type, commit_type)) {
 152                         struct commit *commit = lookup_commit(sha1);
 153                         parse_commit_buffer(commit, buffer, size);
 154                         if (!commit->buffer) {
 155                                 commit->buffer = buffer;
 156                                 buffer = NULL;
 157                         }
 158                         obj = &commit->object;
 159                 } else if (!strcmp(type, tag_type)) {
 160                         struct tag *tag = lookup_tag(sha1);
 161                         parse_tag_buffer(tag, buffer, size);
 162                         obj = &tag->object;
 163                 } else {
 164                         obj = NULL;
 165                 }
 166                 free(buffer);
 167                 return obj;
 168         }
 169         return NULL;
 170 }
 171
 172 struct object_list *object_list_insert(struct object *item,
 173                                        struct object_list **list_p)
 174 {
 175         struct object_list *new_list = xmalloc(sizeof(struct object_list));
 176         new_list->item = item;
 177         new_list->next = *list_p;
 178         *list_p = new_list;
 179         return new_list;
 180 }
 181
 182 void object_list_append(struct object *item,
 183                         struct object_list **list_p)
 184 {
 185         while (*list_p) {
 186                 list_p = &((*list_p)->next);
 187         }
 188         *list_p = xmalloc(sizeof(struct object_list));
 189         (*list_p)->next = NULL;
 190         (*list_p)->item = item;
 191 }
 192
 193 unsigned object_list_length(struct object_list *list)
 194 {
 195         unsigned ret = 0;
 196         while (list) {
 197                 list = list->next;
 198                 ret++;
 199         }
 200         return ret;
 201 }
 202
 203 int object_list_contains(struct object_list *list, struct object *obj)
 204 {
 205         while (list) {
 206                 if (list->item == obj)
 207                         return 1;
 208                 list = list->next;
 209         }
 210         return 0;
 211 }
 212
 213 void add_object_array(struct object *obj, const char *name, struct object_array *array)
 214 {
 215         unsigned nr = array->nr;
 216         unsigned alloc = array->alloc;
 217         struct object_array_entry *objects = array->objects;
 218
 219         if (nr >= alloc) {
 220                 alloc = (alloc + 32) * 2;
 221                 objects = xrealloc(objects, alloc * sizeof(*objects));
 222                 array->alloc = alloc;
 223                 array->objects = objects;
 224         }
 225         objects[nr].item = obj;
 226         objects[nr].name = name;
 227         array->nr = ++nr;
 228 }