git/vcs-svn/sliding_window.h
Jonathan Nieder fbdd4f6fb4 vcs-svn: cap number of bytes read from sliding view
Introduce a "max_off" field in struct sliding_view, roughly
representing a maximum number of bytes that can be read from "file".
If it is set to a nonnegative integer, a call to move_window()
attempting to put the right endpoint beyond that offset will return
an error instead.

The idea is to use this when applying Subversion-format deltas to
prevent reads past the end of the preimage (which has known length).
Without such a check, corrupt deltas would cause svn-fe to block
indefinitely when data in the input pipe is exhausted.

Inspired-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-06-15 02:15:22 -05:00

19 lines
376 B
C

#ifndef SLIDING_WINDOW_H_
#define SLIDING_WINDOW_H_
#include "strbuf.h"
struct sliding_view {
struct line_buffer *file;
off_t off;
size_t width;
off_t max_off; /* -1 means unlimited */
struct strbuf buf;
};
#define SLIDING_VIEW_INIT(input, len) { (input), 0, 0, (len), STRBUF_INIT }
extern int move_window(struct sliding_view *view, off_t off, size_t width);
#endif