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/* Copyright (C) 1993,1997,1998,1999,2000,2002 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 "libioP.h"
#ifdef __STDC__
#include <stdlib.h>
#include <stddef.h>
#endif
#ifdef _LIBC
# include <shlib-compat.h>
#else
# define _IO_new_fopen fopen
#endif
_IO_FILE *
__fopen_maybe_mmap (fp)
_IO_FILE *fp;
{
#ifdef _G_HAVE_MMAP
if (fp->_flags & _IO_NO_WRITES)
{
/* We use the file in read-only mode. This could mean we can
mmap the file and use it without any copying. But not all
file descriptors are for mmap-able objects and on 32-bit
machines we don't want to map files which are too large since
this would require too much virtual memory. */
struct _G_stat64 st;
if (_IO_SYSSTAT (fp, &st) == 0
&& S_ISREG (st.st_mode) && st.st_size != 0
/* Limit the file size to 1MB for 32-bit machines. */
&& (sizeof (ptrdiff_t) > 4 || st.st_size < 1*1024*1024))
{
/* Try to map the file. */
void *p;
# ifdef _G_MMAP64
p = _G_MMAP64 (NULL, st.st_size, PROT_READ, MAP_PRIVATE,
fp->_fileno, 0);
# else
p = __mmap (NULL, st.st_size, PROT_READ, MAP_PRIVATE,
fp->_fileno, 0);
# endif
if (p != MAP_FAILED)
{
if (
# ifdef _G_LSEEK64
_G_LSEEK64 (fp->_fileno, st.st_size, SEEK_SET)
# else
__lseek (fp->_fileno, st.st_size, SEEK_SET)
# endif
!= st.st_size)
{
/* We cannot search the file. Don't mmap then. */
__munmap (p, st.st_size);
return fp;
}
/* OK, we managed to map the file. Set the buffer up
and use a special jump table with simplified
underflow functions which never tries to read
anything from the file. */
_IO_setb (fp, p, (char *) p + st.st_size, 0);
_IO_setg (fp, p, p, (char *) p + st.st_size);
if (fp->_mode <= 0)
_IO_JUMPS ((struct _IO_FILE_plus *) fp) = &_IO_file_jumps_mmap;
else
_IO_JUMPS ((struct _IO_FILE_plus *) fp) = &_IO_wfile_jumps_mmap;
fp->_wide_data->_wide_vtable = &_IO_wfile_jumps_mmap;
fp->_offset = st.st_size;
}
}
}
#endif
return fp;
}
_IO_FILE *
__fopen_internal (filename, mode, is32)
const char *filename;
const char *mode;
int is32;
{
struct locked_FILE
{
struct _IO_FILE_plus fp;
#ifdef _IO_MTSAFE_IO
_IO_lock_t lock;
#endif
struct _IO_wide_data wd;
} *new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
if (new_f == NULL)
return NULL;
#ifdef _IO_MTSAFE_IO
new_f->fp.file._lock = &new_f->lock;
#endif
#if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
_IO_no_init (&new_f->fp.file, 0, 0, &new_f->wd, &_IO_wfile_jumps);
#else
_IO_no_init (&new_f->fp.file, 1, 0, NULL, NULL);
#endif
_IO_JUMPS (&new_f->fp) = &_IO_file_jumps;
_IO_file_init (&new_f->fp);
#if !_IO_UNIFIED_JUMPTABLES
new_f->fp.vtable = NULL;
#endif
if (_IO_file_fopen ((_IO_FILE *) new_f, filename, mode, is32) != NULL)
return __fopen_maybe_mmap (&new_f->fp.file);
_IO_un_link (&new_f->fp);
free (new_f);
return NULL;
}
_IO_FILE *
_IO_new_fopen (filename, mode)
const char *filename;
const char *mode;
{
return __fopen_internal (filename, mode, 1);
}
#ifdef _LIBC
strong_alias (_IO_new_fopen, __new_fopen)
versioned_symbol (libc, _IO_new_fopen, _IO_fopen, GLIBC_2_1);
versioned_symbol (libc, __new_fopen, fopen, GLIBC_2_1);
#endif
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