mercurial/bdiff.h

subsetmaker: rework the antichain generation to be usable

Before this, antichain computation can run for 10s of hours without completion in
sight. We use a more direct approach in the computation to keep the computation
in complexity in check. With good result.

We can now have a full antichain computation on mozilla-try in about one
minute. Which is usable.

Differential Revision: https://phab.mercurial-scm.org/D12396

#ifndef HG_BDIFF_H
#define HG_BDIFF_H

#include "compat.h"

struct bdiff_line {
	int hash, n, e;
	ssize_t len;
	const char *l;
};

struct bdiff_hunk;
struct bdiff_hunk {
	int a1, a2, b1, b2;
	struct bdiff_hunk *next;
};

int bdiff_splitlines(const char *a, ssize_t len, struct bdiff_line **lr);
int bdiff_diff(struct bdiff_line *a, int an, struct bdiff_line *b, int bn,
               struct bdiff_hunk *base);
void bdiff_freehunks(struct bdiff_hunk *l);

#endif