undo-files: clean existing files up before writing new one
the in the initial design of journal/undo interaction, ages ago, new file always
overwrote previous files. This is no longer the case for a long while, so it is
time to properly clean things up before writing new ones.
Otherwise, inconsistent "undo" state might exist on disk, leading `hg rollback`
to misbehave (more that intended).
#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