debug/vsprintf_chk.c

   1 /* Copyright (C) 1994, 1997, 1999-2003, 2004, 2006, 2009
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <stdarg.h>
  21 #include <stdio.h>
  22 #include "../libio/libioP.h"
  23 #include "../libio/strfile.h"
  24
  25
  26 static int _IO_str_chk_overflow (_IO_FILE *fp, int c) __THROW;
  27
  28 static int
  29 _IO_str_chk_overflow (fp, c)
  30      _IO_FILE *fp;
  31      int c;
  32 {
  33   /* When we come to here this means the user supplied buffer is
  34      filled.  */
  35   __chk_fail ();
  36 }
  37
  38
  39 static const struct _IO_jump_t _IO_str_chk_jumps =
  40 {
  41   JUMP_INIT_DUMMY,
  42   JUMP_INIT(finish, _IO_str_finish),
  43   JUMP_INIT(overflow, _IO_str_chk_overflow),
  44   JUMP_INIT(underflow, INTUSE(_IO_str_underflow)),
  45   JUMP_INIT(uflow, INTUSE(_IO_default_uflow)),
  46   JUMP_INIT(pbackfail, INTUSE(_IO_str_pbackfail)),
  47   JUMP_INIT(xsputn, INTUSE(_IO_default_xsputn)),
  48   JUMP_INIT(xsgetn, INTUSE(_IO_default_xsgetn)),
  49   JUMP_INIT(seekoff, INTUSE(_IO_str_seekoff)),
  50   JUMP_INIT(seekpos, _IO_default_seekpos),
  51   JUMP_INIT(setbuf, _IO_default_setbuf),
  52   JUMP_INIT(sync, _IO_default_sync),
  53   JUMP_INIT(doallocate, INTUSE(_IO_default_doallocate)),
  54   JUMP_INIT(read, _IO_default_read),
  55   JUMP_INIT(write, _IO_default_write),
  56   JUMP_INIT(seek, _IO_default_seek),
  57   JUMP_INIT(close, _IO_default_close),
  58   JUMP_INIT(stat, _IO_default_stat),
  59   JUMP_INIT(showmanyc, _IO_default_showmanyc),
  60   JUMP_INIT(imbue, _IO_default_imbue)
  61 };
  62
  63
  64 int
  65 ___vsprintf_chk (char *s, int flags, size_t slen, const char *format,
  66                  va_list args)
  67 {
  68   _IO_strfile f;
  69   int ret;
  70 #ifdef _IO_MTSAFE_IO
  71   f._sbf._f._lock = NULL;
  72 #endif
  73
  74   if (slen == 0)
  75     __chk_fail ();
  76
  77   _IO_no_init (&f._sbf._f, _IO_USER_LOCK, -1, NULL, NULL);
  78   _IO_JUMPS (&f._sbf) = &_IO_str_chk_jumps;
  79   s[0] = '\0';
  80   _IO_str_init_static_internal (&f, s, slen - 1, s);
  81
  82   /* For flags > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n
  83      can only come from read-only format strings.  */
  84   if (flags > 0)
  85     f._sbf._f._flags2 |= _IO_FLAGS2_FORTIFY;
  86
  87   ret = INTUSE(_IO_vfprintf) (&f._sbf._f, format, args);
  88
  89   *f._sbf._f._IO_write_ptr = '\0';
  90   return ret;
  91 }
  92 ldbl_hidden_def (___vsprintf_chk, __vsprintf_chk)
  93 ldbl_strong_alias (___vsprintf_chk, __vsprintf_chk)