stdio-common/fxprintf.c

   1 /* Copyright (C) 2005-2020 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.org>.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <stdarg.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <wchar.h>
  24 #include <libioP.h>
  25
  26 static int
  27 locked_vfxprintf (FILE *fp, const char *fmt, va_list ap,
  28                   unsigned int mode_flags)
  29 {
  30   if (_IO_fwide (fp, 0) <= 0)
  31     return __vfprintf_internal (fp, fmt, ap, mode_flags);
  32
  33   /* We must convert the narrow format string to a wide one.
  34      Each byte can produce at most one wide character.  */
  35   wchar_t *wfmt;
  36   mbstate_t mbstate;
  37   int res;
  38   int used_malloc = 0;
  39   size_t len = strlen (fmt) + 1;
  40
  41   if (__glibc_unlikely (len > SIZE_MAX / sizeof (wchar_t)))
  42     {
  43       __set_errno (EOVERFLOW);
  44       return -1;
  45     }
  46   if (__libc_use_alloca (len * sizeof (wchar_t)))
  47     wfmt = alloca (len * sizeof (wchar_t));
  48   else if ((wfmt = malloc (len * sizeof (wchar_t))) == NULL)
  49     return -1;
  50   else
  51     used_malloc = 1;
  52
  53   memset (&mbstate, 0, sizeof mbstate);
  54   res = __mbsrtowcs (wfmt, &fmt, len, &mbstate);
  55
  56   if (res != -1)
  57     res = __vfwprintf_internal (fp, wfmt, ap, mode_flags);
  58
  59   if (used_malloc)
  60     free (wfmt);
  61
  62   return res;
  63 }
  64
  65 int
  66 __vfxprintf (FILE *fp, const char *fmt, va_list ap,
  67              unsigned int mode_flags)
  68 {
  69   if (fp == NULL)
  70     fp = stderr;
  71   _IO_flockfile (fp);
  72   int res = locked_vfxprintf (fp, fmt, ap, mode_flags);
  73   _IO_funlockfile (fp);
  74   return res;
  75 }
  76
  77 int
  78 __fxprintf (FILE *fp, const char *fmt, ...)
  79 {
  80   va_list ap;
  81   va_start (ap, fmt);
  82   int res = __vfxprintf (fp, fmt, ap, 0);
  83   va_end (ap);
  84   return res;
  85 }
  86
  87 int
  88 __fxprintf_nocancel (FILE *fp, const char *fmt, ...)
  89 {
  90   if (fp == NULL)
  91     fp = stderr;
  92
  93   va_list ap;
  94   va_start (ap, fmt);
  95   _IO_flockfile (fp);
  96   int save_flags2 = fp->_flags2;
  97   fp->_flags2 |= _IO_FLAGS2_NOTCANCEL;
  98
  99   int res = locked_vfxprintf (fp, fmt, ap, 0);
 100
 101   fp->_flags2 = save_flags2;
 102   _IO_funlockfile (fp);
 103   va_end (ap);
 104   return res;
 105 }