vfs: add a `register_file` method on the vfs class
This is used by the fncache vfs to register new file. Until now, `fncache` have
been doing this "automatically" by monitoring write pattern. However this is
fragile and when we copy files in place by other means, we need something more
robuts. So we add an explicit method to do so.
Differential Revision: https://phab.mercurial-scm.org/D10851
#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