progress: retry ferr.flush() and .write() on EINTR (issue5532)
See the inline comment how this could mitigate the issue.
I couldn't reproduce the exact problem on my Linux machine, but there are
at least two people who got EINTR in progress.py, and it seems file_write()
of Python 2 is fundamentally broken [1]. Let's make something in on 4.2.
[1]: https://hg.python.org/cpython/file/v2.7.13/Objects/fileobject.c#l1850
#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