1 #include "stdio_impl.h"
2 #include <string.h>
3 #include "param_check.h"
4
5 #define MIN(a,b) ((a)<(b) ? (a) : (b))
fgets(char * restrict s,int n,FILE * restrict f)6 char *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 PARAM_CHECK(f);
13
14 FLOCK(f);
15
16 if (n--<=1) {
17 f->mode |= f->mode-1;
18 FUNLOCK(f);
19 if (n) return 0;
20 *s = 0;
21 return s;
22 }
23
24 while (n) {
25 if (f->rpos != f->rend) {
26 z = memchr(f->rpos, '\n', MIN(f->rend - f->rpos, n));
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
49
50 weak_alias(fgets, fgets_unlocked);
51