Merge branch 'lt/unitype' into js/c-merge-recursive
[git] / 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 **obj_hash;
9 static int nr_objs, obj_hash_size;
10
11 unsigned int get_max_object_index(void)
12 {
13         return obj_hash_size;
14 }
15
16 struct object *get_indexed_object(unsigned int idx)
17 {
18         return obj_hash[idx];
19 }
20
21 const char *type_names[] = {
22         "none", "commit", "tree", "blob", "tag",
23         "bad type 5", "bad type 6", "delta", "bad",
24 };
25
26 static unsigned int hash_obj(struct object *obj, unsigned int n)
27 {
28         unsigned int hash = *(unsigned int *)obj->sha1;
29         return hash % n;
30 }
31
32 static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
33 {
34         int j = hash_obj(obj, size);
35
36         while (hash[j]) {
37                 j++;
38                 if (j >= size)
39                         j = 0;
40         }
41         hash[j] = obj;
42 }
43
44 static int hashtable_index(const unsigned char *sha1)
45 {
46         unsigned int i;
47         memcpy(&i, sha1, sizeof(unsigned int));
48         return (int)(i % obj_hash_size);
49 }
50
51 struct object *lookup_object(const unsigned char *sha1)
52 {
53         int i;
54         struct object *obj;
55
56         if (!obj_hash)
57                 return NULL;
58
59         i = hashtable_index(sha1);
60         while ((obj = obj_hash[i]) != NULL) {
61                 if (!memcmp(sha1, obj->sha1, 20))
62                         break;
63                 i++;
64                 if (i == obj_hash_size)
65                         i = 0;
66         }
67         return obj;
68 }
69
70 static void grow_object_hash(void)
71 {
72         int i;
73         int new_hash_size = obj_hash_size < 32 ? 32 : 2 * obj_hash_size;
74         struct object **new_hash;
75
76         new_hash = calloc(new_hash_size, sizeof(struct object *));
77         for (i = 0; i < obj_hash_size; i++) {
78                 struct object *obj = obj_hash[i];
79                 if (!obj)
80                         continue;
81                 insert_obj_hash(obj, new_hash, new_hash_size);
82         }
83         free(obj_hash);
84         obj_hash = new_hash;
85         obj_hash_size = new_hash_size;
86 }
87
88 void created_object(const unsigned char *sha1, struct object *obj)
89 {
90         obj->parsed = 0;
91         obj->used = 0;
92         obj->type = OBJ_NONE;
93         obj->flags = 0;
94         memcpy(obj->sha1, sha1, 20);
95
96         if (obj_hash_size - 1 <= nr_objs * 2)
97                 grow_object_hash();
98
99         insert_obj_hash(obj, obj_hash, obj_hash_size);
100         nr_objs++;
101 }
102
103 struct object *lookup_object_type(const unsigned char *sha1, const char *type)
104 {
105         if (!type) {
106                 return lookup_unknown_object(sha1);
107         } else if (!strcmp(type, blob_type)) {
108                 return &lookup_blob(sha1)->object;
109         } else if (!strcmp(type, tree_type)) {
110                 return &lookup_tree(sha1)->object;
111         } else if (!strcmp(type, commit_type)) {
112                 return &lookup_commit(sha1)->object;
113         } else if (!strcmp(type, tag_type)) {
114                 return &lookup_tag(sha1)->object;
115         } else {
116                 error("Unknown type %s", type);
117                 return NULL;
118         }
119 }
120
121 union any_object {
122         struct object object;
123         struct commit commit;
124         struct tree tree;
125         struct blob blob;
126         struct tag tag;
127 };
128
129 struct object *lookup_unknown_object(const unsigned char *sha1)
130 {
131         struct object *obj = lookup_object(sha1);
132         if (!obj) {
133                 union any_object *ret = xcalloc(1, sizeof(*ret));
134                 created_object(sha1, &ret->object);
135                 ret->object.type = OBJ_NONE;
136                 return &ret->object;
137         }
138         return obj;
139 }
140
141 struct object *parse_object(const unsigned char *sha1)
142 {
143         unsigned long size;
144         char type[20];
145         void *buffer = read_sha1_file(sha1, type, &size);
146         if (buffer) {
147                 struct object *obj;
148                 if (check_sha1_signature(sha1, buffer, size, type) < 0)
149                         printf("sha1 mismatch %s\n", sha1_to_hex(sha1));
150                 if (!strcmp(type, blob_type)) {
151                         struct blob *blob = lookup_blob(sha1);
152                         parse_blob_buffer(blob, buffer, size);
153                         obj = &blob->object;
154                 } else if (!strcmp(type, tree_type)) {
155                         struct tree *tree = lookup_tree(sha1);
156                         obj = &tree->object;
157                         if (!tree->object.parsed) {
158                                 parse_tree_buffer(tree, buffer, size);
159                                 buffer = NULL;
160                         }
161                 } else if (!strcmp(type, commit_type)) {
162                         struct commit *commit = lookup_commit(sha1);
163                         parse_commit_buffer(commit, buffer, size);
164                         if (!commit->buffer) {
165                                 commit->buffer = buffer;
166                                 buffer = NULL;
167                         }
168                         obj = &commit->object;
169                 } else if (!strcmp(type, tag_type)) {
170                         struct tag *tag = lookup_tag(sha1);
171                         parse_tag_buffer(tag, buffer, size);
172                         obj = &tag->object;
173                 } else {
174                         obj = NULL;
175                 }
176                 free(buffer);
177                 return obj;
178         }
179         return NULL;
180 }
181
182 struct object_list *object_list_insert(struct object *item,
183                                        struct object_list **list_p)
184 {
185         struct object_list *new_list = xmalloc(sizeof(struct object_list));
186         new_list->item = item;
187         new_list->next = *list_p;
188         *list_p = new_list;
189         return new_list;
190 }
191
192 void object_list_append(struct object *item,
193                         struct object_list **list_p)
194 {
195         while (*list_p) {
196                 list_p = &((*list_p)->next);
197         }
198         *list_p = xmalloc(sizeof(struct object_list));
199         (*list_p)->next = NULL;
200         (*list_p)->item = item;
201 }
202
203 unsigned object_list_length(struct object_list *list)
204 {
205         unsigned ret = 0;
206         while (list) {
207                 list = list->next;
208                 ret++;
209         }
210         return ret;
211 }
212
213 int object_list_contains(struct object_list *list, struct object *obj)
214 {
215         while (list) {
216                 if (list->item == obj)
217                         return 1;
218                 list = list->next;
219         }
220         return 0;
221 }
222
223 void add_object_array(struct object *obj, const char *name, struct object_array *array)
224 {
225         unsigned nr = array->nr;
226         unsigned alloc = array->alloc;
227         struct object_array_entry *objects = array->objects;
228
229         if (nr >= alloc) {
230                 alloc = (alloc + 32) * 2;
231                 objects = xrealloc(objects, alloc * sizeof(*objects));
232                 array->alloc = alloc;
233                 array->objects = objects;
234         }
235         objects[nr].item = obj;
236         objects[nr].name = name;
237         array->nr = ++nr;
238 }