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-rw-r--r--debug/vasprintf_chk.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/debug/vasprintf_chk.c b/debug/vasprintf_chk.c
new file mode 100644
index 0000000000..6105516d59
--- /dev/null
+++ b/debug/vasprintf_chk.c
@@ -0,0 +1,97 @@
+/* Copyright (C) 1995,1997,1999-2002,2004,2006,2008
+   Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.
+
+   As a special exception, if you link the code in this file with
+   files compiled with a GNU compiler to produce an executable,
+   that does not cause the resulting executable to be covered by
+   the GNU Lesser General Public License.  This exception does not
+   however invalidate any other reasons why the executable file
+   might be covered by the GNU Lesser General Public License.
+   This exception applies to code released by its copyright holders
+   in files containing the exception.  */
+
+#include <malloc.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdio_ext.h>
+#include "../libio/libioP.h"
+#include "../libio/strfile.h"
+
+int
+__vasprintf_chk (char **result_ptr, int flags, const char *format,
+		 va_list args)
+{
+  /* Initial size of the buffer to be used.  Will be doubled each time an
+     overflow occurs.  */
+  const _IO_size_t init_string_size = 100;
+  char *string;
+  _IO_strfile sf;
+  int ret;
+  _IO_size_t needed;
+  _IO_size_t allocated;
+  /* No need to clear the memory here (unlike for open_memstream) since
+     we know we will never seek on the stream.  */
+  string = (char *) malloc (init_string_size);
+  if (string == NULL)
+    return -1;
+#ifdef _IO_MTSAFE_IO
+  sf._sbf._f._lock = NULL;
+#endif
+  _IO_no_init ((_IO_FILE *) &sf._sbf, _IO_USER_LOCK, -1, NULL, NULL);
+  _IO_JUMPS ((struct _IO_FILE_plus *) &sf._sbf) = &_IO_str_jumps;
+  _IO_str_init_static_internal (&sf, string, init_string_size, string);
+  sf._sbf._f._flags &= ~_IO_USER_BUF;
+  sf._s._allocate_buffer = (_IO_alloc_type) malloc;
+  sf._s._free_buffer = (_IO_free_type) free;
+
+  /* For flags > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n
+     can only come from read-only format strings.  */
+  if (flags > 0)
+    sf._sbf._f._flags2 |= _IO_FLAGS2_FORTIFY;
+
+  ret = INTUSE(_IO_vfprintf) (&sf._sbf._f, format, args);
+  if (ret < 0)
+    {
+      free (sf._sbf._f._IO_buf_base);
+      return ret;
+    }
+  /* Only use realloc if the size we need is of the same (binary)
+     order of magnitude then the memory we allocated.  */
+  needed = sf._sbf._f._IO_write_ptr - sf._sbf._f._IO_write_base + 1;
+  allocated = sf._sbf._f._IO_write_end - sf._sbf._f._IO_write_base;
+  if ((allocated >> 1) <= needed)
+    *result_ptr = (char *) realloc (sf._sbf._f._IO_buf_base, needed);
+  else
+    {
+      *result_ptr = (char *) malloc (needed);
+      if (*result_ptr != NULL)
+	{
+	  memcpy (*result_ptr, sf._sbf._f._IO_buf_base, needed - 1);
+	  free (sf._sbf._f._IO_buf_base);
+	}
+      else
+	/* We have no choice, use the buffer we already have.  */
+	*result_ptr = (char *) realloc (sf._sbf._f._IO_buf_base, needed);
+    }
+  if (*result_ptr == NULL)
+    *result_ptr = sf._sbf._f._IO_buf_base;
+  (*result_ptr)[needed - 1] = '\0';
+  return ret;
+}
+libc_hidden_def (__vasprintf_chk)