nsz Git - musl/blob - src/stdio/getdelim.c

   1 #include "stdio_impl.h"
   2
   3 #define MIN(a,b) ((a)<(b) ? (a) : (b))
   4
   5 ssize_t getdelim(char **restrict s, size_t *restrict n, int delim, FILE *restrict f)
   6 {
   7         char *tmp;
   8         unsigned char *z;
   9         size_t k;
  10         size_t i=0;
  11         int c;
  12
  13         if (!n || !s) {
  14                 errno = EINVAL;
  15                 return -1;
  16         }
  17
  18         if (!*s) *n=0;
  19
  20         FLOCK(f);
  21
  22         for (;;) {
  23                 z = memchr(f->rpos, delim, f->rend - f->rpos);
  24                 k = z ? z - f->rpos + 1 : f->rend - f->rpos;
  25                 if (i+k >= *n) {
  26                         if (k >= SIZE_MAX/2-i) goto oom;
  27                         *n = i+k+2;
  28                         if (*n < SIZE_MAX/4) *n *= 2;
  29                         tmp = realloc(*s, *n);
  30                         if (!tmp) {
  31                                 *n = i+k+2;
  32                                 tmp = realloc(*s, *n);
  33                                 if (!tmp) goto oom;
  34                         }
  35                         *s = tmp;
  36                 }
  37                 memcpy(*s+i, f->rpos, k);
  38                 f->rpos += k;
  39                 i += k;
  40                 if (z) break;
  41                 if ((c = getc_unlocked(f)) == EOF) {
  42                         if (!i || !feof(f)) {
  43                                 FUNLOCK(f);
  44                                 return -1;
  45                         }
  46                         break;
  47                 }
  48                 if (((*s)[i++] = c) == delim) break;
  49         }
  50         (*s)[i] = 0;
  51
  52         FUNLOCK(f);
  53
  54         return i;
  55 oom:
  56         FUNLOCK(f);
  57         errno = ENOMEM;
  58         return -1;
  59 }
  60
  61 weak_alias(getdelim, __getdelim);