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[v3] correctly handle NUL characters in stringbufs, plus cosmetic tweaks



This patch fixes a critical bug in stringbufs, as well as some other
completely uninteresting changes.  Lots of analysis on the libstdc++ list
about the NUL bug; basically, if a stringstream tries to read data out of
a string which has embedded NULs, then we incorrectly stop at the first one.

Tested on x86/linux, applied to trunk and branch.


2001-07-13  Phil Edwards  <pme@sources.redhat.com>

	* include/bits/std_sstream.h (basic_stringbuf::basic_stringbuf(string):
	Initialize _M_string with pointer-and-size constructor, not just
	pointer.  Fix some comments.
	* testsuite/21_strings/ctor_copy_dtor.cc (test03):  New test.
	* testsuite/27_io/stringbuf.cc (test02):  Remove unused variable.
	(test03):  Add embedded-NUL tests.

	* mkcheck.in:  When printing totals, match the order of the tests.
	* include/bits/stringfwd.h:  Use same declaration keywords.
	* include/bits/std_iosfwd.h:  Cosmetic spacing.


Index: mkcheck.in
===================================================================
RCS file: /cvs/gcc/gcc/libstdc++-v3/mkcheck.in,v
retrieving revision 1.59
diff -u -3 -p -r1.59 mkcheck.in
--- mkcheck.in	2001/05/22 18:48:19	1.59
+++ mkcheck.in	2001/07/13 20:42:55
@@ -436,7 +436,7 @@ TEST_TIME_END=$($TIMER_COMMAND)
 # grep can count faster than we can...
 total_failures=`expr ${shared_fail} + ${static_fail}`
 total_successes=`expr ${shared_pass} + ${static_pass}`
-resultstext="pass/fail results:  ${shared_pass}/${shared_fail} shared + ${static_pass}/${static_fail} static = ${total_successes}/${total_failures} total"
+resultstext="pass/fail results:  ${static_pass}/${static_fail} static + ${shared_pass}/${shared_fail} shared = ${total_successes}/${total_failures} total"
 if [ $total_failures -eq 0 ]; then
     resultstext="${resultstext}, WIN WIN"
 fi
Index: include/bits/std_iosfwd.h
===================================================================
RCS file: /cvs/gcc/gcc/libstdc++-v3/include/bits/std_iosfwd.h,v
retrieving revision 1.7
diff -u -3 -p -r1.7 std_iosfwd.h
--- std_iosfwd.h	2001/06/26 21:22:57	1.7
+++ std_iosfwd.h	2001/07/13 20:42:55
@@ -100,7 +100,7 @@ namespace std 
   typedef basic_ios<char> 		ios;
   typedef basic_streambuf<char> 	streambuf;
   typedef basic_istream<char> 		istream;
-   typedef basic_ostream<char> 		ostream;
+  typedef basic_ostream<char> 		ostream;
   typedef basic_iostream<char> 		iostream;
   typedef basic_stringbuf<char> 	stringbuf;
   typedef basic_istringstream<char> 	istringstream;
Index: include/bits/std_sstream.h
===================================================================
RCS file: /cvs/gcc/gcc/libstdc++-v3/include/bits/std_sstream.h,v
retrieving revision 1.7
diff -u -3 -p -r1.7 std_sstream.h
--- std_sstream.h	2001/06/12 22:14:08	1.7
+++ std_sstream.h	2001/07/13 20:42:55
@@ -75,7 +75,7 @@ namespace std
       explicit 
       basic_stringbuf(const __string_type& __str,
 		      ios_base::openmode __mode = ios_base::in | ios_base::out)
-      : __streambuf_type(), _M_string(__str.c_str())
+      : __streambuf_type(), _M_string(__str.data(), __str.size())
       { _M_stringbuf_init(__mode); }
 
       // Get and set:
@@ -84,7 +84,7 @@ namespace std
       {
 	if (_M_mode & ios_base::out)
 	  {
-	    // This is the deal: _M_string.size() is value that
+	    // This is the deal: _M_string.size() is a value that
 	    // represents the size of the intial string that makes
 	    // _M_string, and may not be the correct size of the
 	    // current stringbuf internal buffer.
@@ -116,7 +116,7 @@ namespace std
 	// re-allocation of the internal string object, _M_string.
 	_M_buf_size = _M_string.size();
 
-	// NB: Start ostringstream buffers at 1024 bytes. This is an
+	// NB: Start ostringstream buffers at 512 bytes. This is an
 	// experimental value (pronounced "arbitrary" in some of the
 	// hipper english-speaking countries), and can be changed to
 	// suite particular needs.
Index: include/bits/stringfwd.h
===================================================================
RCS file: /cvs/gcc/gcc/libstdc++-v3/include/bits/stringfwd.h,v
retrieving revision 1.3
diff -u -3 -p -r1.3 stringfwd.h
--- stringfwd.h	2001/03/07 22:22:41	1.3
+++ stringfwd.h	2001/07/13 20:42:55
@@ -43,9 +43,9 @@ namespace std
   template<class _CharT>
     struct char_traits;
   
-  template<> class char_traits<char>;
+  template<> struct char_traits<char>;
 #ifdef _GLIBCPP_USE_WCHAR_T
-  template<> class char_traits<wchar_t>;
+  template<> struct char_traits<wchar_t>;
 #endif
 
   template<typename _Alloc> 
Index: testsuite/21_strings/ctor_copy_dtor.cc
===================================================================
RCS file: /cvs/gcc/gcc/libstdc++-v3/testsuite/21_strings/ctor_copy_dtor.cc,v
retrieving revision 1.6
diff -u -3 -p -r1.6 ctor_copy_dtor.cc
--- ctor_copy_dtor.cc	2001/05/12 16:51:41	1.6
+++ ctor_copy_dtor.cc	2001/07/13 20:42:55
@@ -1,6 +1,6 @@
 // 1999-06-04 bkoz
 
-// Copyright (C) 1999, 2000 Free Software Foundation, Inc.
+// Copyright (C) 1999, 2000, 2001 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
@@ -176,9 +176,28 @@ void test02()
 #endif
 }
 
+void test03()
+{
+  bool test = true;
+  const char* with_nulls = "This contains \0 a zero byte.";
+
+  // These are tests to see how basic_string handles data with NUL
+  // bytes.  Obviously basic_string(char*) will halt at the first one, but
+  // nothing else should.
+  std::string s1 (with_nulls, 28);
+  VERIFY( s1.size() == 28 );
+  std::string s2 (s1);
+  VERIFY( s2.size() == 28 );
+
+#ifdef DEBUG_ASSERT
+  assert(test);
+#endif
+}
+
 int main()
 { 
   test01();
   test02();
+  test03();
   return 0;
 }
Index: testsuite/27_io/stringbuf.cc
===================================================================
RCS file: /cvs/gcc/gcc/libstdc++-v3/testsuite/27_io/stringbuf.cc,v
retrieving revision 1.4
diff -u -3 -p -r1.4 stringbuf.cc
--- stringbuf.cc	2001/05/12 16:51:42	1.4
+++ stringbuf.cc	2001/07/13 20:42:55
@@ -1,6 +1,6 @@
 // 981208 bkoz test functionality of basic_stringbuf for char_type == char
 
-// Copyright (C) 1997-1999, 2000 Free Software Foundation, Inc.
+// Copyright (C) 1997-2001 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
@@ -54,7 +54,6 @@ bool test02() {
 // test member functions
 bool test03() {
   bool test = true;
-  std::string str_tmp;
 
   //stringbuf::str()
   VERIFY( strb_01.str() == str_01 );
@@ -71,6 +70,18 @@ bool test03() {
   VERIFY( d1 != d2 ); //these should be the same
   VERIFY( str_01.length() == d1 );  
   VERIFY( strb_01.str() == strb_03.str() ); //ditto
+
+  // stringbuf::str(string&) and stringbuf::stringbuf(string&), where the
+  // string in question contains embedded NUL characters.  Note that in this
+  // embedded-NUL situation, the size must be passed to the string ctor.
+  std::string str_nulls ("eschew \0 obfuscation", 20);  // tested in 21_strings
+  std::stringbuf strb_normal (str_01);
+  std::stringbuf strb_nulls (str_nulls);
+  strb_normal.str(str_nulls);  // tried using 'strb_01' rather than declaring
+                               // another variable, but then test04 broke!
+  VERIFY( strb_nulls.in_avail() == str_nulls.size()  );
+  VERIFY( strb_nulls.str().size() == 20              );
+  VERIFY( strb_normal.in_avail() == str_nulls.size() );
 
 #ifdef DEBUG_ASSERT
   assert(test);


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