1 #include "stdio_impl.h"
2 #include <string.h>
3 #ifndef __LITEOS__
4 #include "param_check.h"
5 #endif
6
7 #define MIN(a,b) ((a)<(b) ? (a) : (b))
fgets(char *restrict s, int n, FILE *restrict f)8 char *fgets(char *restrict s, int n, FILE *restrict f)
9 {
10 char *p = s;
11 unsigned char *z;
12 size_t k;
13 int c;
14 #ifndef __LITEOS__
15 PARAM_CHECK(f);
16 #endif
17 FLOCK(f);
18
19 if (n<=1) {
20 f->mode |= f->mode-1;
21 FUNLOCK(f);
22 if (n<1) return 0;
23 *s = 0;
24 return s;
25 }
26 n--;
27
28 while (n) {
29 if (f->rpos != f->rend) {
30 z = memchr(f->rpos, '\n', MIN(f->rend - f->rpos, n));
31 k = z ? z - f->rpos + 1 : f->rend - f->rpos;
32 k = MIN(k, n);
33 memcpy(p, f->rpos, k);
34 f->rpos += k;
35 p += k;
36 n -= k;
37 if (z || !n) break;
38 }
39 if ((c = getc_unlocked(f)) < 0) {
40 if (p==s || !feof(f)) s = 0;
41 break;
42 }
43 n--;
44 if ((*p++ = c) == '\n') break;
45 }
46 if (s) *p = 0;
47
48 FUNLOCK(f);
49
50 return s;
51 }
52
53
54 weak_alias(fgets, fgets_unlocked);
55