mercurial/mpatch.h

revset: add optimization for heads(commonancestors())

Previously, the only way to get these commits were (tested on
mozilla-central):

hg perfrevset 'heads(::a7cf55 and ::d8b15)'
! wall 4.988366 comb 4.960000 user 4.780000 sys 0.180000 (best of 3)

After this patch:

(python)
hg perfrevset 'heads(commonancestors(a7cf55 + d8b15))'
! wall 0.002155 comb 0.000000 user 0.000000 sys 0.000000 (best of 1107)

(C)
hg perfrevset 'heads(commonancestors(a7cf55 + d8b15))'
! wall 0.000568 comb 0.000000 user 0.000000 sys 0.000000 (best of 4646)

#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