fstream.tcc (basic_filebuf::seekoff): Use codecvt::length to handle variable-width stateless encodings correctly.

2003-09-10  Petur Runolfsson  <peturr02@ru.is>

	* include/bits/fstream.tcc (basic_filebuf::seekoff):
	Use codecvt::length to handle variable-width stateless encodings
	correctly.
	* testsuite/27_io/basic_filebuf/seekoff/wchar_t/1.cc: New test.
	* testsuite/27_io/basic_filebuf/seekoff/wchar_t/2.cc: New test.

From-SVN: r71271

4 files changed, 249 insertions, 3 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 6df79ce..d99e42b 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,11 @@
+2003-09-10  Petur Runolfsson  <peturr02@ru.is>
+
+	* include/bits/fstream.tcc (basic_filebuf::seekoff):
+	Use codecvt::length to handle variable-width stateless encodings
+	correctly.
+	* testsuite/27_io/basic_filebuf/seekoff/wchar_t/1.cc: New test.
+	* testsuite/27_io/basic_filebuf/seekoff/wchar_t/2.cc: New test.
+
 2003-09-10  Alan Modra  <amodra@bigpond.net.au>
 
 	* config/io/basic_file_stdio.cc (_M_open_mode): Assign __p_mode
diff --git a/libstdc++-v3/include/bits/fstream.tcc b/libstdc++-v3/include/bits/fstream.tcc
index 6b77fb0..3117555 100644
--- a/libstdc++-v3/include/bits/fstream.tcc
+++ b/libstdc++-v3/include/bits/fstream.tcc
@@ -593,7 +593,7 @@ namespace std
 	  // Ditch any pback buffers to avoid confusion.
 	  _M_destroy_pback();
 
-	  off_type __computed_off = __off;	  
+	  off_type __computed_off = __off * __width;
 	  if (this->pbase() < this->pptr())
 	    {
 	      // Part one: update the output sequence.
@@ -603,13 +603,26 @@ namespace std
 	      _M_output_unshift();
 	    }
 	  else if (_M_reading && __way == ios_base::cur)
-	    __computed_off += this->gptr() - this->egptr();
+	    {
+	      if (_M_codecvt->always_noconv())
+		__computed_off += this->gptr() - this->egptr();
+	      else
+		{
+		  // Calculate offset from _M_ext_buf that corresponds
+		  // to gptr().
+		  const int __gptr_off =
+		    _M_codecvt->length(_M_state_cur, _M_ext_buf, _M_ext_next,
+				       this->gptr() - this->eback());
+		  __computed_off += _M_ext_buf + __gptr_off - _M_ext_end;
+		}
+	    }
 	  
 	  // Returns pos_type(off_type(-1)) in case of failure.
-	  __ret = _M_file.seekoff(__computed_off * __width, __way, __mode);
+	  __ret = _M_file.seekoff(__computed_off, __way, __mode);
 	  
 	  _M_reading = false;
 	  _M_writing = false;
+	  _M_ext_next = _M_ext_end = _M_ext_buf;
 	  _M_set_buffer(-1);
 	}
       _M_last_overflowed = false;	
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/1.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/1.cc
new file mode 100644
index 0000000..f3f3cc7
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/1.cc
@@ -0,0 +1,136 @@
+// 2003-09-08  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ 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.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+// Check that basic_filebuf::seekoff handles UTF-8 when open for input.
+void test01()
+{
+  using namespace std;
+  typedef wfilebuf::pos_type pos_type;
+  typedef wfilebuf::int_type int_type;
+
+  bool test = true;
+  const char name[] = "tmp_seekoff-1.tst";
+  const int_type eof = wfilebuf::traits_type::eof();
+
+  const char cstr[] =
+    "\x1\x2\x3\x4\x5\x6\x7\x8\x9\xa\xb\xc\xd\xe\xf\x10\x11\x12\x13"
+    "\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20!\"#$%&"
+    "'()*+,-./0123456789:;<=>?@}~\x7f\xc2\x80\xc2\x81\xc2\x82\xc2"
+    "\x83\xc2\x84\xc2\x85\xc2\x86\xc2\x87\xc2\x88\xc2\x89\xc2\x8a"
+    "\xc2\x8b\xc2\x8c\xc2\x8d\xc2\x8e\xc2\x8f\xc2\x90\xc2\x91\xc2"
+    "\x92\xc2\x93\xc2\x94\xc2\x95\xc2\x96\xc2\x97\xc2\x98\xc2\x99"
+    "\xc2\x9a\xc2\x9b\xc2\x9c\xc3\xba\xc3\xbb\xc3\xbc\xc3\xbd\xc3"
+    "\xbe\xc3\xbf\xc4\x80\xc4\x81\xc4\x82\xc4\x83\xc4\x84\xc4\x85"
+    "\xc4\x86\xc4\x87\xc4\x88\xc4\x89\xc4\x8a\xc4\x8b\xc4\x8c\xc4"
+    "\x8d\xc4\x8e\xc4\x8f\xc4\x90\xc4\x91\xc4\x92\xc4\x93\xc4\x94"
+    "\xc4\x95\xc4\x96\xc4\x97\xc4\x98\xc4\x99\xdf\xb8\xdf\xb9\xdf"
+    "\xba\xdf\xbb\xdf\xbc\xdf\xbd\xdf\xbe\xdf\xbf\xe0\xa0\x80\xe0"
+    "\xa0\x81\xe0\xa0\x82\xe0\xa0\x83\xe0\xa0\x84\xe0\xa0\x85\xe0"
+    "\xa0\x86\xe0\xa0\x87\xe0\xa0\x88\xe0\xa0\x89\xe0\xa0\x8a\xe0"
+    "\xa0\x8b\xe0\xa0\x8c\xe0\xa0\x8d\xe0\xa0\x8e\xe0\xa0\x8f\xe0"
+    "\xa0\x90\xe0\xa0\x91\xe0\xa0\x92\xe0\xa0\x93\xe0\xa0\x94\xe0"
+    "\xa0\x95\xe0\xa0\x96\xe0\xa0\x97\x1\x2\x4\x8\x10\x20@\xc2\x80"
+    "\xc4\x80\xc8\x80\xd0\x80\xe0\xa0\x80\xe1\x80\x80\xe2\x80\x80"
+    "\xe4\x80\x80\xe8\x80\x80\xf0\x90\x80\x80\xf0\xa0\x80\x80\xf1"
+    "\x80\x80\x80\xf2\x80\x80\x80\xf4\x80\x80\x80\xf8\x88\x80\x80"
+    "\x80\xf8\x90\x80\x80\x80\xf8\xa0\x80\x80\x80\xf9\x80\x80\x80"
+    "\x80\xfa\x80\x80\x80\x80\xfc\x84\x80\x80\x80\x80\xfc\x88\x80"
+    "\x80\x80\x80\xfc\x90\x80\x80\x80\x80\xfc\xa0\x80\x80\x80\x80"
+    "\xfd\x80\x80\x80\x80\x80";
+
+  const wchar_t wstr[] = {
+    0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc,
+    0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, L'!',
+    L'"', L'#', L'$', L'%', L'&', L'\'', L'(', L')', L'*', L'+',
+    L',', L'-', L'.', L'/', L'0', L'1', L'2', L'3', L'4', L'5',
+    L'6', L'7', L'8', L'9', L':', L';', L'<', L'=', L'>', L'?',
+    L'@', L'}', L'~', 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,
+    0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+    0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
+    0x9a, 0x9b, 0x9c, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 0x100,
+    0x101, 0x102, 0x103, 0x104, 0x105, 0x106, 0x107, 0x108, 0x109,
+    0x10a, 0x10b, 0x10c, 0x10d, 0x10e, 0x10f, 0x110, 0x111, 0x112,
+    0x113, 0x114, 0x115, 0x116, 0x117, 0x118, 0x119, 0x7f8, 0x7f9,
+    0x7fa, 0x7fb, 0x7fc, 0x7fd, 0x7fe, 0x7ff, 0x800, 0x801, 0x802,
+    0x803, 0x804, 0x805, 0x806, 0x807, 0x808, 0x809, 0x80a, 0x80b,
+    0x80c, 0x80d, 0x80e, 0x80f, 0x810, 0x811, 0x812, 0x813, 0x814,
+    0x815, 0x816, 0x817, 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, L'@',
+    0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000,
+    0x10000, 0x20000, 0x40000, 0x80000, 0x100000, 0x200000, 0x400000,
+    0x800000, 0x1000000, 0x2000000, 0x4000000, 0x8000000, 0x10000000,
+    0x20000000, 0x40000000, 0x0
+  };
+
+  const size_t clen = sizeof(cstr) / sizeof(cstr[0]);
+  const size_t wlen = sizeof(wstr) / sizeof(wstr[0]);
+
+  const int loops = 2 * BUFSIZ / wlen;
+  locale loc = __gnu_test::try_named_locale("se_NO.UTF-8");
+
+  FILE* file = fopen(name, "w");
+  for (int i = 0; i < loops; ++i)
+    fwrite(cstr, 1, clen, file);
+  fclose(file);
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.open(name, ios_base::in);
+
+  pos_type p1 = fb.pubseekoff(0, ios_base::cur);
+  pos_type end = fb.pubseekoff(0, ios_base::end);
+  pos_type beg = fb.pubseekoff(0, ios_base::beg);
+  VERIFY( p1 == beg );
+
+  const size_t limit = wlen * loops;
+  for (size_t index = 0; index < limit; ++index)
+    {
+      // Call seekoff at pseudo-random intervals.
+      if (index % 5 == 0 || index % 7 == 0)
+	{
+	  pos_type p2 = fb.pubseekoff(0, ios_base::cur);
+	  VERIFY( p2 != pos_type(-1) );
+	}
+      int_type c1 = fb.sbumpc();
+      VERIFY( c1 != eof );
+      VERIFY( c1 == wstr[index % wlen] );
+    }
+
+  pos_type p3 = fb.pubseekoff(0, ios_base::cur);
+  VERIFY( p3 == end );
+
+  int_type c2 = fb.sbumpc();
+  VERIFY( c2 == eof );
+
+  fb.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/2.cc b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/2.cc
new file mode 100644
index 0000000..9ad978b
--- /dev/null
+++ b/libstdc++-v3/testsuite/27_io/basic_filebuf/seekoff/wchar_t/2.cc
@@ -0,0 +1,89 @@
+// 2003-09-08  Petur Runolfsson  <peturr02@ru.is>
+
+// Copyright (C) 2003 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ 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.
+
+// 27.8.1.4 Overridden virtual functions
+
+#include <fstream>
+#include <locale>
+#include <cstdio>
+#include <testsuite_hooks.h>
+
+// Check that basic_filebuf::seekoff handles UTF-8 when open for input and
+// output.
+void test02()
+{
+  using namespace std;
+  typedef wfilebuf::int_type int_type;
+  bool test = true;
+  const char name[] = "tmp_seekoff-2.tst";
+
+  locale loc = __gnu_test::try_named_locale("se_NO.UTF-8");
+
+  const size_t size = 10;
+  wchar_t buf[size];
+  streamsize n;
+
+  wfilebuf fb;
+  fb.pubimbue(loc);
+  fb.open(name, ios_base::in | ios_base::out | ios_base::trunc);
+
+  n = fb.sputn(L"\xa0st", 3);
+  VERIFY( n == 3 );
+  
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, 2);
+  VERIFY( n == 2 );
+  VERIFY( !wmemcmp(buf, L"\xa0s", 2) );
+
+  fb.pubseekoff(0, ios_base::cur);
+  n = fb.sputn(L"\xb2R", 2);
+  VERIFY( n == 2 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, size);
+  VERIFY( n == 4 );
+  VERIFY( !wmemcmp(buf, L"\xa0s\xb2R", 4) );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sputn(L"\x90m\x92n\x94", 5);
+  VERIFY( n == 5 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, 2);
+  VERIFY( n == 2 );
+  VERIFY( !wmemcmp(buf, L"\x90m", 2) );
+
+  fb.pubseekoff(0, ios_base::end);
+  n = fb.sputn(L"I\xbfJ", 3);
+  VERIFY( n == 3 );
+
+  fb.pubseekoff(0, ios_base::beg);
+  n = fb.sgetn(buf, size);
+  VERIFY( n == 8 );
+  VERIFY( !wmemcmp(buf, L"\x90m\x92n\x94I\xbfJ", 8) );
+
+  fb.close();
+}
+
+int main()
+{
+  test02();
+  return 0;
+}