mercurial/mpatch.h

setup: move cffi stuff to mercurial/cffi

This patch moves all setup*cffi stuff to mercurial/cffi to make the root
directory cleaner. The idea was from mpm [1]:

  > It seems like we could have a fair amount of cffi definitions, and
  > cluttering the root directory (or mercurial/) with them is probably not
  > a great long-term solution. We could probably add a cffi/ directory
  > under mercurial/ to parallel pure/.

[1]: https://www.mercurial-scm.org/pipermail/mercurial-devel/2016-July/086442.html

#ifndef _HG_MPATCH_H_
#define _HG_MPATCH_H_

#define MPATCH_ERR_NO_MEM -3
#define MPATCH_ERR_CANNOT_BE_DECODED -2
#define MPATCH_ERR_INVALID_PATCH -1

struct mpatch_frag {
	int start, end, len;
	const char *data;
};

struct mpatch_flist {
	struct mpatch_frag *base, *head, *tail;
};

int mpatch_decode(const char *bin, ssize_t len, struct mpatch_flist** res);
ssize_t mpatch_calcsize(ssize_t len, struct mpatch_flist *l);
void mpatch_lfree(struct mpatch_flist *a);
int mpatch_apply(char *buf, const char *orig, ssize_t len,
	struct mpatch_flist *l);
struct mpatch_flist *mpatch_fold(void *bins,
	struct mpatch_flist* (*get_next_item)(void*, ssize_t),
	ssize_t start, ssize_t end);

#endif