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) return 0;
19		*s = 0;
20		return s;
21	}
22
23	while (n) {
24		if (f->rpos != f->rend) {
25			z = memchr(f->rpos, '\n', f->rend - f->rpos);
26			k = z ? z - f->rpos + 1 : f->rend - f->rpos;
27			k = MIN(k, (size_t)n);
28			memcpy(p, f->rpos, k);
29			f->rpos += k;
30			p += k;
31			n -= k;
32			if (z || !n) break;
33		}
34		if ((c = getc_unlocked(f)) < 0) {
35			if (p==s || !feof(f)) s = 0;
36			break;
37		}
38		n--;
39		if ((*p++ = c) == '\n') break;
40	}
41	if (s) *p = 0;
42
43	FUNLOCK(f);
44
45	return s;
46}