mercurial/mpatch.h

smartset: use native set operations as fast paths

For set operations like "&" and "-", where we know both basesets have their
sets ready, and the first set is sorted, use the native Python set
operations as a fast path.

Note: "+" is not optimized as that will break the ordering.

This leads to noticeable improvements on performance:

  revset                                | before | after | delta
  ----------------------------------------------------------------
  draft() & draft() & draft() & draft() |    776 |   477 | -39%
  draft() + draft() + draft() + draft() |   2849 |  2864 |
  draft() - draft() + draft() - draft() |    943 |   240 | -75%
  draft() - draft() - draft() - draft() |    557 |   197 | -64%

  (time measured in microseconds)

#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