libc/stdio/vswprintf.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 #include <stdarg.h>
  10 #include <wchar.h>
  11
  12
  13 /* NB: this file is not used if __USE_OLD_VFPRINTF__ */
  14
  15 #ifndef __STDIO_BUFFERS
  16 #warning Skipping vswprintf since no buffering!
  17 #else  /* __STDIO_BUFFERS */
  18
  19 int vswprintf(wchar_t *__restrict buf, size_t size,
  20                           const wchar_t * __restrict format, va_list arg)
  21 {
  22         FILE f;
  23         int rv;
  24
  25         f.__filedes = __STDIO_STREAM_FAKE_VSWPRINTF_FILEDES;
  26         f.__modeflags = (__FLAG_WIDE|__FLAG_WRITEONLY|__FLAG_WRITING);
  27
  28         f.__ungot_width[0] = 0;
  29 #ifdef __STDIO_MBSTATE
  30         __INIT_MBSTATE(&(f.__state));
  31 #endif /* __STDIO_MBSTATE */
  32
  33 #ifdef __UCLIBC_HAS_THREADS__
  34         f.__user_locking = 1;           /* Set user locking. */
  35         STDIO_INIT_MUTEX(f.__lock);
  36 #endif /* __UCLIBC_HAS_THREADS__ */
  37
  38         f.__nextopen = NULL;
  39
  40         if (size > ((SIZE_MAX - (size_t) buf)/sizeof(wchar_t))) {
  41                 size = ((SIZE_MAX - (size_t) buf)/sizeof(wchar_t));
  42         }
  43
  44         f.__bufstart = (unsigned char *) buf;
  45         f.__bufend = (unsigned char *) (buf + size);
  46         __STDIO_STREAM_INIT_BUFREAD_BUFPOS(&f);
  47         __STDIO_STREAM_DISABLE_GETC(&f);
  48         __STDIO_STREAM_DISABLE_PUTC(&f);
  49
  50         rv = _vfwprintf_internal(&f, format, arg);
  51
  52         /* NOTE: Return behaviour differs from snprintf... */
  53         if (f.__bufpos == f.__bufend) {
  54                 rv = -1;
  55                 if (size) {
  56                         f.__bufpos = (unsigned char *) (((wchar_t *) f.__bufpos) - 1);
  57                 }
  58         }
  59         if (size) {
  60                 *((wchar_t *) f.__bufpos) = 0;
  61         }
  62         return rv;
  63 }
  64 libc_hidden_def(vswprintf)
  65
  66 #endif /* __STDIO_BUFFERS */