X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=delta.h;h=31d1820f80f2887d51808170fc86585ada42d42e;hb=f0243f26f6d8403cd8e83c7d498c81e01a1f1735;hp=8e4efdf4acb568a4bd439884911d0ee947bd7f92;hpb=d1af002dc608be3213ba18df1a99ced0ab42e6d6;p=git.git diff --git a/delta.h b/delta.h index 8e4efdf4..31d1820f 100644 --- a/delta.h +++ b/delta.h @@ -4,18 +4,31 @@ /* handling of delta buffers */ extern void *diff_delta(void *from_buf, unsigned long from_size, void *to_buf, unsigned long to_size, - unsigned long *delta_size); + unsigned long *delta_size, unsigned long max_size); extern void *patch_delta(void *src_buf, unsigned long src_size, void *delta_buf, unsigned long delta_size, unsigned long *dst_size); -/* handling of delta objects */ -struct delta; -struct object_list; -extern struct delta *lookup_delta(unsigned char *sha1); -extern int parse_delta_buffer(struct delta *item, void *buffer, unsigned long size); -extern int parse_delta(struct delta *item, unsigned char sha1); -extern int process_deltas(void *src, unsigned long src_size, - const char *src_type, struct object_list *delta); +/* the smallest possible delta size is 4 bytes */ +#define DELTA_SIZE_MIN 4 + +/* + * This must be called twice on the delta data buffer, first to get the + * expected reference buffer size, and again to get the result buffer size. + */ +static inline unsigned long get_delta_hdr_size(const unsigned char **datap) +{ + const unsigned char *data = *datap; + unsigned char cmd = *data++; + unsigned long size = cmd & ~0x80; + int i = 7; + while (cmd & 0x80) { + cmd = *data++; + size |= (cmd & ~0x80) << i; + i += 7; + } + *datap = data; + return size; +} #endif