mercurial/mpatch.h

evolution: report new unstable changesets

This adds a transaction summary callback that reports the number of
new orphan, content-divergent and phase-divergent changesets.

The code for reporting it is based on the code from the evolve
extension, but simplified a bit. It simply counts the numbers for each
kind of instability before and after the transaction. That's obviously
not very efficient, but it's easy to reason about, so I'm doing this
as a first step that can make us quite confident about the test case
changes. We can optimize it later and make sure that the tests are not
affected. The code has been used in the evolve extension for a long
time and has apparently been sufficiently fast, so it doesn't seem
like a pressing issue.

Unlike the evolve extension's version of this report, this version
applies to all commands (or all transactions run as part of any
command, to be exact).

Differential Revision: https://phab.mercurial-scm.org/D1867

#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