git/object.c

268 строки
5.8 KiB
C
Исходник Обычный вид История

#include "cache.h"
#include "object.h"
#include "blob.h"
#include "tree.h"
#include "commit.h"
#include "tag.h"
struct object **objs;
static int nr_objs;
int obj_allocs;
int track_object_refs = 1;
static int hashtable_index(const unsigned char *sha1)
{
unsigned int i;
memcpy(&i, sha1, sizeof(unsigned int));
return (int)(i % obj_allocs);
}
static int find_object(const unsigned char *sha1)
{
int i;
if (!objs)
return -1;
i = hashtable_index(sha1);
while (objs[i]) {
if (memcmp(sha1, objs[i]->sha1, 20) == 0)
return i;
i++;
if (i == obj_allocs)
i = 0;
}
return -1 - i;
}
struct object *lookup_object(const unsigned char *sha1)
{
int pos = find_object(sha1);
if (pos >= 0)
return objs[pos];
return NULL;
}
void created_object(const unsigned char *sha1, struct object *obj)
{
int pos;
obj->parsed = 0;
memcpy(obj->sha1, sha1, 20);
obj->type = NULL;
obj->refs = NULL;
obj->used = 0;
if (obj_allocs - 1 <= nr_objs * 2) {
int i, count = obj_allocs;
obj_allocs = (obj_allocs < 32 ? 32 : 2 * obj_allocs);
objs = xrealloc(objs, obj_allocs * sizeof(struct object *));
memset(objs + count, 0, (obj_allocs - count)
* sizeof(struct object *));
for (i = 0; i < obj_allocs; i++)
if (objs[i]) {
int j = find_object(objs[i]->sha1);
if (j != i) {
j = -1 - j;
objs[j] = objs[i];
objs[i] = NULL;
}
}
}
pos = find_object(sha1);
if (pos >= 0)
die("Inserting %s twice\n", sha1_to_hex(sha1));
pos = -pos-1;
objs[pos] = obj;
nr_objs++;
}
struct object_refs *alloc_object_refs(unsigned count)
{
struct object_refs *refs;
size_t size = sizeof(*refs) + count*sizeof(struct object *);
refs = xmalloc(size);
memset(refs, 0, size);
refs->count = count;
return refs;
}
static int compare_object_pointers(const void *a, const void *b)
{
const struct object * const *pa = a;
const struct object * const *pb = b;
if (*pa == *pb)
return 0;
else if (*pa < *pb)
return -1;
else
return 1;
}
void set_object_refs(struct object *obj, struct object_refs *refs)
{
unsigned int i, j;
/* Do not install empty list of references */
if (refs->count < 1) {
free(refs);
return;
}
/* Sort the list and filter out duplicates */
qsort(refs->ref, refs->count, sizeof(refs->ref[0]),
compare_object_pointers);
for (i = j = 1; i < refs->count; i++) {
if (refs->ref[i] != refs->ref[i - 1])
refs->ref[j++] = refs->ref[i];
}
if (j < refs->count) {
/* Duplicates were found - reallocate list */
size_t size = sizeof(*refs) + j*sizeof(struct object *);
refs->count = j;
refs = xrealloc(refs, size);
}
for (i = 0; i < refs->count; i++)
refs->ref[i]->used = 1;
obj->refs = refs;
}
void mark_reachable(struct object *obj, unsigned int mask)
{
if (!track_object_refs)
die("cannot do reachability with object refs turned off");
/* If we've been here already, don't bother */
if (obj->flags & mask)
return;
obj->flags |= mask;
if (obj->refs) {
const struct object_refs *refs = obj->refs;
unsigned i;
for (i = 0; i < refs->count; i++)
mark_reachable(refs->ref[i], mask);
}
}
struct object *lookup_object_type(const unsigned char *sha1, const char *type)
{
if (!type) {
return lookup_unknown_object(sha1);
} else if (!strcmp(type, blob_type)) {
return &lookup_blob(sha1)->object;
} else if (!strcmp(type, tree_type)) {
return &lookup_tree(sha1)->object;
} else if (!strcmp(type, commit_type)) {
return &lookup_commit(sha1)->object;
} else if (!strcmp(type, tag_type)) {
return &lookup_tag(sha1)->object;
} else {
error("Unknown type %s", type);
return NULL;
}
}
union any_object {
struct object object;
struct commit commit;
struct tree tree;
struct blob blob;
struct tag tag;
};
struct object *lookup_unknown_object(const unsigned char *sha1)
{
struct object *obj = lookup_object(sha1);
if (!obj) {
union any_object *ret = xmalloc(sizeof(*ret));
memset(ret, 0, sizeof(*ret));
created_object(sha1, &ret->object);
ret->object.type = NULL;
return &ret->object;
}
return obj;
}
struct object *parse_object(const unsigned char *sha1)
{
unsigned long size;
char type[20];
void *buffer = read_sha1_file(sha1, type, &size);
if (buffer) {
struct object *obj;
if (check_sha1_signature(sha1, buffer, size, type) < 0)
printf("sha1 mismatch %s\n", sha1_to_hex(sha1));
if (!strcmp(type, "blob")) {
struct blob *blob = lookup_blob(sha1);
parse_blob_buffer(blob, buffer, size);
obj = &blob->object;
} else if (!strcmp(type, "tree")) {
struct tree *tree = lookup_tree(sha1);
parse_tree_buffer(tree, buffer, size);
obj = &tree->object;
} else if (!strcmp(type, "commit")) {
struct commit *commit = lookup_commit(sha1);
parse_commit_buffer(commit, buffer, size);
if (!commit->buffer) {
commit->buffer = buffer;
buffer = NULL;
}
obj = &commit->object;
} else if (!strcmp(type, "tag")) {
struct tag *tag = lookup_tag(sha1);
parse_tag_buffer(tag, buffer, size);
obj = &tag->object;
} else {
obj = NULL;
}
free(buffer);
return obj;
}
return NULL;
}
struct object_list *object_list_insert(struct object *item,
struct object_list **list_p)
{
struct object_list *new_list = xmalloc(sizeof(struct object_list));
new_list->item = item;
new_list->next = *list_p;
*list_p = new_list;
return new_list;
}
void object_list_append(struct object *item,
struct object_list **list_p)
{
while (*list_p) {
list_p = &((*list_p)->next);
}
*list_p = xmalloc(sizeof(struct object_list));
(*list_p)->next = NULL;
(*list_p)->item = item;
}
unsigned object_list_length(struct object_list *list)
{
unsigned ret = 0;
while (list) {
list = list->next;
ret++;
}
return ret;
}
int object_list_contains(struct object_list *list, struct object *obj)
{
while (list) {
if (list->item == obj)
return 1;
list = list->next;
}
return 0;
}