annotate mercurial/bdiff.h @ 31650:23391acfc421

py3: fix manifestdict.fastdelta() to be compatible with memoryview

This doesn't look nice, but a straightforward way to support Python 3.
bytes(m[start:end]) is needed because a memoryview doesn't support ordering
operations. On Python 2, m[start:end] returns a bytes object even if m is
a buffer, so calling bytes() should involve no additional copy.

I'm tired of trying cleaner alternatives, including:

 a. extend memoryview to be compatible with buffer type
    => memoryview is not an acceptable base type
 b. wrap memoryview by buffer-like class
    => zlib complains it isn't bytes-like

#ifndef _HG_BDIFF_H_
#define _HG_BDIFF_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