libc/stdio/fgets.c

   1 /* Copyright (C) 2004       Manuel Novoa III    <mjn3@codepoet.org>
   2  *
   3  * GNU Library General Public License (LGPL) version 2 or later.
   4  *
   5  * Dedicated to Toni.  See uClibc/DEDICATION.mjn3 for details.
   6  */
   7
   8 #include "_stdio.h"
   9
  10
  11 #ifdef __DO_UNLOCKED
  12
  13
  14 char *fgets_unlocked(char *__restrict s, int n,
  15                                            register FILE * __restrict stream)
  16 {
  17         register char *p;
  18         int c;
  19
  20         __STDIO_STREAM_VALIDATE(stream);
  21
  22         /* Should we assert here?  Or set errno?  Or just fail... */
  23         if (n <= 0) {
  24 /*              __set_errno(EINVAL); */
  25                 goto ERROR;
  26         }
  27
  28         p = s;
  29
  30         while (--n) {
  31                 if (__STDIO_STREAM_CAN_USE_BUFFER_GET(stream)) {
  32                         if ((*p++ = __STDIO_STREAM_BUFFER_GET(stream)) == '\n') {
  33                                 break;
  34                         }
  35                 } else {
  36                         if ((c = __fgetc_unlocked(stream)) == EOF) {
  37                                 if (__FERROR_UNLOCKED(stream)) {
  38                                         goto ERROR;
  39                                 }
  40                                 break;
  41                         }
  42                         if ((*p++ = c) == '\n') {
  43                                 break;
  44                         }
  45                 }
  46         }
  47
  48         if (p > s) {
  49                 *p = 0;
  50                 return s;
  51         }
  52
  53  ERROR:
  54         return NULL;
  55 }
  56 libc_hidden_def(fgets_unlocked)
  57
  58 #ifndef __UCLIBC_HAS_THREADS__
  59 strong_alias(fgets_unlocked,fgets)
  60 libc_hidden_def(fgets)
  61 #endif
  62
  63 #elif defined __UCLIBC_HAS_THREADS__
  64
  65 char *fgets(char *__restrict s, int n,
  66                         register FILE * __restrict stream)
  67 {
  68         char *retval;
  69         __STDIO_AUTO_THREADLOCK_VAR;
  70
  71         __STDIO_AUTO_THREADLOCK(stream);
  72
  73         retval = fgets_unlocked(s, n, stream);
  74
  75         __STDIO_AUTO_THREADUNLOCK(stream);
  76
  77         return retval;
  78 }
  79 libc_hidden_def(fgets)
  80
  81 #endif