1#include "stdio_impl.h"
 2#include <string.h>
 3
 4#define MIN(a,b) ((a)<(b) ? (a) : (b))
 5
 6char *fgets(char *restrict s, int n, FILE *restrict f)
 7{
 8	char *p = s;
 9	unsigned char *z;
10	size_t k;
11	int c;
12
13	FLOCK(f);
14
15	if (n<=1) {
16		f->mode |= f->mode-1;
17		FUNLOCK(f);
18		if (n<1) return 0;
19		*s = 0;
20		return s;
21	}
22	n--;
23
24	while (n) {
25		if (f->rpos != f->rend) {
26			z = memchr(f->rpos, '\n', f->rend - f->rpos);
27			k = z ? z - f->rpos + 1 : f->rend - f->rpos;
28			k = MIN(k, n);
29			memcpy(p, f->rpos, k);
30			f->rpos += k;
31			p += k;
32			n -= k;
33			if (z || !n) break;
34		}
35		if ((c = getc_unlocked(f)) < 0) {
36			if (p==s || !feof(f)) s = 0;
37			break;
38		}
39		n--;
40		if ((*p++ = c) == '\n') break;
41	}
42	if (s) *p = 0;
43
44	FUNLOCK(f);
45
46	return s;
47}
48
49weak_alias(fgets, fgets_unlocked);