view mercurial/bdiff.h @ 40009:842ffcf1d42f

storageutil: extract most of emitrevisions() to standalone function

As part of implementing a storage backend, I found myself copying
most of revlog.emitrevisions(). This code is highly nuanced and it
bothered me greatly to be copying such low-level code.

This commit extracts the bulk of revlog.emitrevisions() into a
new standalone function. In order to make the function generally
usable, all "self" function calls that aren't exposed on the
ifilestorage interface are passed in via callable arguments.

No meaningful behavior should have changed as part of the port.

Upcoming commits will tweak behavior to make the code more
generically usable.

Differential Revision: https://phab.mercurial-scm.org/D4803

#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