[PATCH] Fix wide stdio

[Jakub Jelinek <jakub at redhat dot com>]

Hi!

On
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <wchar.h>
#include <error.h>

int
main (int argc, char **argv)
{
  char name[] = "/tmp/wprintf.out.XXXXXX";
  int fd;
  FILE *fp;
  fd = mkstemp (name);
  fp = fdopen (dup (fd), "a");
  if (fp == NULL)
    error (EXIT_FAILURE, errno, "fdopen(,\"a\")");
  setvbuf (fp, NULL, _IONBF, 0);
  fwprintf (fp, L"hello.\n");
  fclose (fp);
  return EXIT_SUCCESS;
}
testcase from Arjan we attempt to munmap fp->_shortbuf (which is fortunately
not page aligned and thus the munmap just fails).
The problem seems to be that we use just one _IO_USER_BUF bit, for two
different buffers (fp->_IO_buf_base and fp->_wide_data->_IO_buf_base).
If wide orientation used just one of these buffers, we could just clear
the narrow buffers in _IO_fwide when switching to wide orientation, but
when wide oriented, we actually use both buffers at the same time,
and they aren't necessarily both user buffers or both non-user buffers.
So, IMHO we just have to use a different bit for the
fp->_wide_data->_IO_buf_base allocation status (whether we are supposed
to free it or not).
Additionally, as _IO_new_file_close_it unconditionally overwrites
fp->_flags, we need to free not just the wide buffer for wide oriented
streams, but also the narrow one.

2006-11-24  Jakub Jelinek  <jakub@redhat.com>

	* libio/libio.h (_IO_FLAGS2_USER_WBUF): Define.
	* libio/wgenops.c (_IO_wsetb, _IO_wdefault_finish): Test and set
	_IO_FLAGS2_USER_WBUF bit in _flags2 instead of _IO_USER_BUF bit
	in _flags.
	* libio/wstrops.c (_IO_wstr_overflow, enlarge_userbuf,
	_IO_wstr_finish): Likewise.
	* libio/wmemstream.c (open_wmemstream): Likewise.
	* libio/fileops.c (_IO_new_file_close_it): Call _IO_set[bgp]
	even for wide streams.

--- libc/libio/libio.h.jj	2006-11-24 12:51:29.000000000 +0100
+++ libc/libio/libio.h	2006-11-24 13:30:23.000000000 +0100
@@ -142,6 +142,7 @@
 #ifdef _LIBC
 # define _IO_FLAGS2_FORTIFY 4
 #endif
+#define _IO_FLAGS2_USER_WBUF 8
 
 /* These are "formatting flags" matching the iostream fmtflags enum values. */
 #define _IO_SKIPWS 01
--- libc/libio/wgenops.c.jj	2006-11-24 12:51:29.000000000 +0100
+++ libc/libio/wgenops.c	2006-11-24 13:30:23.000000000 +0100
@@ -115,14 +115,14 @@ _IO_wsetb (f, b, eb, a)
      wchar_t *eb;
      int a;
 {
-  if (f->_wide_data->_IO_buf_base && !(f->_flags & _IO_USER_BUF))
+  if (f->_wide_data->_IO_buf_base && !(f->_flags2 & _IO_FLAGS2_USER_WBUF))
     FREE_BUF (f->_wide_data->_IO_buf_base, _IO_wblen (f) * sizeof (wchar_t));
   f->_wide_data->_IO_buf_base = b;
   f->_wide_data->_IO_buf_end = eb;
   if (a)
-    f->_flags &= ~_IO_USER_BUF;
+    f->_flags2 &= ~_IO_FLAGS2_USER_WBUF;
   else
-    f->_flags |= _IO_USER_BUF;
+    f->_flags2 |= _IO_FLAGS2_USER_WBUF;
 }
 INTDEF(_IO_wsetb)
 
@@ -198,7 +198,7 @@ _IO_wdefault_finish (fp, dummy)
      int dummy;
 {
   struct _IO_marker *mark;
-  if (fp->_wide_data->_IO_buf_base && !(fp->_flags & _IO_USER_BUF))
+  if (fp->_wide_data->_IO_buf_base && !(fp->_flags2 & _IO_FLAGS2_USER_WBUF))
     {
       FREE_BUF (fp->_wide_data->_IO_buf_base,
 		_IO_wblen (fp) * sizeof (wchar_t));
--- libc/libio/wstrops.c.jj	2006-11-24 12:51:29.000000000 +0100
+++ libc/libio/wstrops.c	2006-11-24 13:30:23.000000000 +0100
@@ -88,7 +88,7 @@ _IO_wstr_overflow (fp, c)
   pos = fp->_wide_data->_IO_write_ptr - fp->_wide_data->_IO_write_base;
   if (pos >= (_IO_size_t) (_IO_wblen (fp) + flush_only))
     {
-      if (fp->_flags & _IO_USER_BUF) /* not allowed to enlarge */
+      if (fp->_flags2 & _IO_FLAGS2_USER_WBUF) /* not allowed to enlarge */
 	return WEOF;
       else
 	{
@@ -182,7 +182,7 @@ enlarge_userbuf (_IO_FILE *fp, _IO_off64
   _IO_ssize_t oldend = wd->_IO_write_end - wd->_IO_write_base;
 
   /* Try to enlarge the buffer.  */
-  if (fp->_flags & _IO_USER_BUF)
+  if (fp->_flags2 & _IO_FLAGS2_USER_WBUF)
     /* User-provided buffer.  */
     return 1;
 
@@ -335,7 +335,7 @@ _IO_wstr_finish (fp, dummy)
      _IO_FILE *fp;
      int dummy;
 {
-  if (fp->_wide_data->_IO_buf_base && !(fp->_flags & _IO_USER_BUF))
+  if (fp->_wide_data->_IO_buf_base && !(fp->_flags2 & _IO_FLAGS2_USER_WBUF))
     (((_IO_strfile *) fp)->_s._free_buffer) (fp->_wide_data->_IO_buf_base);
   fp->_wide_data->_IO_buf_base = NULL;
 
--- libc/libio/wmemstream.c.jj	2006-11-24 12:51:29.000000000 +0100
+++ libc/libio/wmemstream.c	2006-11-24 13:30:23.000000000 +0100
@@ -92,7 +92,7 @@ open_wmemstream (bufloc, sizeloc)
   _IO_fwide (&new_f->fp._sf._sbf._f, 1);
   _IO_wstr_init_static (&new_f->fp._sf._sbf._f, buf,
 			_IO_BUFSIZ / sizeof (wchar_t), buf);
-  new_f->fp._sf._sbf._f._flags &= ~_IO_USER_BUF;
+  new_f->fp._sf._sbf._f._flags2 &= ~_IO_FLAGS2_USER_WBUF;
   new_f->fp._sf._s._allocate_buffer = (_IO_alloc_type) malloc;
   new_f->fp._sf._s._free_buffer = (_IO_free_type) free;
 
--- libc/libio/fileops.c.jj	2006-11-24 12:51:29.000000000 +0100
+++ libc/libio/fileops.c	2006-11-24 13:34:37.000000000 +0100
@@ -174,14 +174,8 @@ _IO_new_file_close_it (fp)
   close_status = _IO_SYSCLOSE (fp);
 
   /* Free buffer. */
-  if (fp->_mode <= 0)
-    {
-      INTUSE(_IO_setb) (fp, NULL, NULL, 0);
-      _IO_setg (fp, NULL, NULL, NULL);
-      _IO_setp (fp, NULL, NULL);
-    }
 #if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T
-  else
+  if (fp->_mode > 0)
     {
       if (_IO_have_wbackup (fp))
 	INTUSE(_IO_free_wbackup_area) (fp);
@@ -190,6 +184,9 @@ _IO_new_file_close_it (fp)
       _IO_wsetp (fp, NULL, NULL);
     }
 #endif
+  INTUSE(_IO_setb) (fp, NULL, NULL, 0);
+  _IO_setg (fp, NULL, NULL, NULL);
+  _IO_setp (fp, NULL, NULL);
 
   INTUSE(_IO_un_link) ((struct _IO_FILE_plus *) fp);
   fp->_flags = _IO_MAGIC|CLOSED_FILEBUF_FLAGS;

	Jakub