newlib/libc/reent/getentropyr.c

   1 /* Reentrant version of getentropy system call. */
   2
   3 #include <reent.h>
   4 #include <unistd.h>
   5 #include <_syslist.h>
   6
   7 /* Some targets provides their own versions of these functions.  Those
   8    targets should define REENTRANT_SYSCALLS_PROVIDED in TARGET_CFLAGS.  */
   9
  10 #ifdef _REENT_ONLY
  11 #ifndef REENTRANT_SYSCALLS_PROVIDED
  12 #define REENTRANT_SYSCALLS_PROVIDED
  13 #endif
  14 #endif
  15
  16 #ifndef REENTRANT_SYSCALLS_PROVIDED
  17
  18 /* We use the errno variable used by the system dependent layer.  */
  19 #undef errno
  20 extern int errno;
  21
  22 /*
  23 FUNCTION
  24         <<_getentropy_r>>---Reentrant version of getentropy
  25
  26 INDEX
  27         _getentropy_r
  28
  29 SYNOPSIS
  30         #include <reent.h>
  31         int _getentropy_r(struct _reent *<[ptr]>,
  32                           void *<[buf]>, size_t <[buflen]>);
  33
  34 DESCRIPTION
  35         This is a reentrant version of <<getentropy>>.  It
  36         takes a pointer to the global data block, which holds
  37         <<errno>>.
  38 */
  39
  40 int
  41 _getentropy_r (struct _reent *ptr,
  42      void *buf,
  43      size_t buflen)
  44 {
  45   int ret;
  46
  47   errno = 0;
  48   if ((ret = _getentropy (buf, buflen)) == -1 && errno != 0)
  49     _REENT_ERRNO(ptr) = errno;
  50   return ret;
  51 }
  52
  53 #endif /* ! defined (REENTRANT_SYSCALLS_PROVIDED) */