debug/obprintf_chk.c

   1 /* Print output of stream to given obstack.
   2    Copyright (C) 1996,1997,1999,2000,2001,2002,2003,2004,2005,2006,2008
   3         Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library; if not, write to the Free
  19    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  20    02111-1307 USA.  */
  21
  22
  23 #include <stdlib.h>
  24 #include <libioP.h>
  25 #include "../libio/strfile.h"
  26 #include <assert.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <obstack.h>
  30 #include <stdarg.h>
  31 #include <stdio_ext.h>
  32
  33
  34 struct _IO_obstack_file
  35 {
  36   struct _IO_FILE_plus file;
  37   struct obstack *obstack;
  38 };
  39
  40 extern const struct _IO_jump_t _IO_obstack_jumps attribute_hidden;
  41
  42 int
  43 __obstack_vprintf_chk (struct obstack *obstack, int flags, const char *format,
  44                        va_list args)
  45 {
  46   struct obstack_FILE
  47     {
  48       struct _IO_obstack_file ofile;
  49     } new_f;
  50   int result;
  51   int size;
  52   int room;
  53
  54 #ifdef _IO_MTSAFE_IO
  55   new_f.ofile.file.file._lock = NULL;
  56 #endif
  57
  58   _IO_no_init (&new_f.ofile.file.file, _IO_USER_LOCK, -1, NULL, NULL);
  59   _IO_JUMPS (&new_f.ofile.file) = &_IO_obstack_jumps;
  60   room = obstack_room (obstack);
  61   size = obstack_object_size (obstack) + room;
  62   if (size == 0)
  63     {
  64       /* We have to handle the allocation a bit different since the
  65          `_IO_str_init_static' function would handle a size of zero
  66          different from what we expect.  */
  67
  68       /* Get more memory.  */
  69       obstack_make_room (obstack, 64);
  70
  71       /* Recompute how much room we have.  */
  72       room = obstack_room (obstack);
  73       size = room;
  74
  75       assert (size != 0);
  76     }
  77
  78   _IO_str_init_static_internal ((struct _IO_strfile_ *) &new_f.ofile,
  79                                 obstack_base (obstack),
  80                                 size, obstack_next_free (obstack));
  81   /* Now allocate the rest of the current chunk.  */
  82   assert (size == (new_f.ofile.file.file._IO_write_end
  83                    - new_f.ofile.file.file._IO_write_base));
  84   assert (new_f.ofile.file.file._IO_write_ptr
  85           == (new_f.ofile.file.file._IO_write_base
  86               + obstack_object_size (obstack)));
  87   obstack_blank_fast (obstack, room);
  88
  89   new_f.ofile.obstack = obstack;
  90
  91   /* For flags > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n
  92      can only come from read-only format strings.  */
  93   if (flags > 0)
  94     new_f.ofile.file.file._flags2 |= _IO_FLAGS2_FORTIFY;
  95
  96   result = INTUSE(_IO_vfprintf) (&new_f.ofile.file.file, format, args);
  97
  98   /* Shrink the buffer to the space we really currently need.  */
  99   obstack_blank_fast (obstack, (new_f.ofile.file.file._IO_write_ptr
 100                                 - new_f.ofile.file.file._IO_write_end));
 101
 102   return result;
 103 }
 104 libc_hidden_def (__obstack_vprintf_chk)
 105
 106
 107 int
 108 __obstack_printf_chk (struct obstack *obstack, int flags, const char *format,
 109                       ...)
 110 {
 111   int result;
 112   va_list ap;
 113   va_start (ap, format);
 114   result = __obstack_vprintf_chk (obstack, flags, format, ap);
 115   va_end (ap);
 116   return result;
 117 }