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-rw-r--r--libio/iofdopen.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/libio/iofdopen.c b/libio/iofdopen.c
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index 0000000000..6bb19fa214
--- /dev/null
+++ b/libio/iofdopen.c
@@ -0,0 +1,124 @@
+/*
+Copyright (C) 1993, 1994 Free Software Foundation
+
+This file is part of the GNU IO Library.  This library is free
+software; you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the
+Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+This 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this library; see the file COPYING.  If not, write to the Free
+Software Foundation, 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+As a special exception, if you link this library with files
+compiled with a GNU compiler to produce an executable, this does not cause
+the resulting executable to be covered by the GNU General Public License.
+This exception does not however invalidate any other reasons why
+the executable file might be covered by the GNU General Public License. */
+
+#ifdef __STDC__
+#include <stdlib.h>
+#endif
+#include "libioP.h"
+#include <fcntl.h>
+
+#ifndef _IO_fcntl
+#define _IO_fcntl fcntl
+#endif
+
+_IO_FILE *
+_IO_fdopen (fd, mode)
+     int fd;
+     const char *mode;
+{
+  int read_write;
+  int posix_mode = 0;
+  struct _IO_FILE_plus *fp;
+  int fd_flags;
+
+  switch (*mode++)
+    {
+    case 'r':
+      read_write = _IO_NO_WRITES;
+      break;
+    case 'w':
+      read_write = _IO_NO_READS;
+      break;
+    case 'a':
+      posix_mode = O_APPEND;
+      read_write = _IO_NO_READS|_IO_IS_APPENDING;
+      break;
+    default:
+#ifdef EINVAL
+      errno = EINVAL;
+#endif
+      return NULL;
+  }
+  if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+'))
+    read_write &= _IO_IS_APPENDING;
+#ifdef F_GETFL
+  fd_flags = _IO_fcntl (fd, F_GETFL);
+#ifndef O_ACCMODE
+#define O_ACCMODE (O_RDONLY|O_WRONLY|O_RDWR)
+#endif
+  if (fd_flags == -1
+      || ((fd_flags & O_ACCMODE) == O_RDONLY && !(read_write & _IO_NO_WRITES))
+      || ((fd_flags & O_ACCMODE) == O_WRONLY && !(read_write & _IO_NO_READS)))
+    return NULL;
+
+  /* The May 93 draft of P1003.4/D14.1 (redesignated as 1003.1b)
+     [System Application Program Interface (API) Amendment 1:
+     Realtime Extensions], Rationale B.8.3.3
+     Open a Stream on a File Descriptor says:
+
+         Although not explicitly required by POSIX.1, a good
+         implementation of append ("a") mode would cause the
+         O_APPEND flag to be set.
+
+     (Historical implementations [such as Solaris2] do a one-time
+     seek in fdopen.)
+
+     However, we do not turn O_APPEND off if the mode is "w" (even
+     though that would seem consistent) because that would be more
+     likely to break historical programs.
+     */
+  if ((posix_mode & O_APPEND) && !(fd_flags & O_APPEND))
+    {
+#ifdef F_SETFL
+      if (_IO_fcntl (fd, F_SETFL, fd_flags | O_APPEND) == -1)
+#endif
+	return NULL;
+    }
+#endif
+
+  fp = (struct _IO_FILE_plus *) malloc (sizeof (struct _IO_FILE_plus));
+  if (fp == NULL)
+    return NULL;
+  _IO_init (&fp->file, 0);
+  _IO_JUMPS (&fp->file) = &_IO_file_jumps;
+  _IO_file_init (&fp->file);
+#if  !_IO_UNIFIED_JUMPTABLES
+  fp->vtable = NULL;
+#endif
+  if (_IO_file_attach (&fp->file, fd) == NULL)
+    {
+      _IO_un_link (&fp->file);
+      free (fp);
+      return NULL;
+    }
+  fp->file._flags &= ~_IO_DELETE_DONT_CLOSE;
+
+  fp->file._IO_file_flags =
+    _IO_mask_flags (&fp->file, read_write,
+		    _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
+
+  return (_IO_FILE *) fp;
+}
+
+weak_alias (_IO_fdopen, fdopen)