istream.tcc (operator>>(basic_istream<>&, basic_string<>&)): Use a temporary…

istream.tcc (operator>>(basic_istream<>&, basic_string<>&)): Use a temporary buffer, thus avoiding reallocation for common case.

2004-05-20  Paolo Carlini  <pcarlini@suse.de>

	* include/bits/istream.tcc (operator>>(basic_istream<>&,
	basic_string<>&)): Use a temporary buffer, thus avoiding
	reallocation for common case.
	* testsuite/21_strings/basic_string/inserters_extractors/char/11.cc:
	New.
	* testsuite/21_strings/basic_string/inserters_extractors/wchar_t/11.cc:
	Likewise.

	* include/bits/istream.tcc: Const-ification of a few variables.

	* include/bits/ostream.tcc: Trivial formatting fixes and
	const-ification of some variables.

From-SVN: r82070

libstdc++-v3/ChangeLog

+2004-05-20  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/bits/istream.tcc (operator>>(basic_istream<>&,
+	basic_string<>&)): Use a temporary buffer, thus avoiding
+	reallocation for common case.
+	* testsuite/21_strings/basic_string/inserters_extractors/char/11.cc:
+	New.
+	* testsuite/21_strings/basic_string/inserters_extractors/wchar_t/11.cc:
+	Likewise.
+
+	* include/bits/istream.tcc: Const-ification of a few variables.
+
+	* include/bits/ostream.tcc: Trivial formatting fixes and
+	const-ification of some variables.
+
 2004-05-20  Benjamin Kosnik  <bkoz@redhat.com>
 
 	PR libstdc++/15123

libstdc++-v3/include/bits/istream.tcc

@@ -478,7 +478,7 @@ namespace std
 	{
 	  try
 	    {
-	      int_type __cb = this->rdbuf()->sbumpc();
+	      const int_type __cb = this->rdbuf()->sbumpc();
 	      // 27.6.1.1 paragraph 3
 	      if (!traits_type::eq_int_type(__cb, traits_type::eof()))
 		{
@@ -876,7 +876,8 @@ namespace std
 	  if (!this->fail())
 	    {
 	      // 136.  seekp, seekg setting wrong streams?
-	      pos_type __p = this->rdbuf()->pubseekpos(__pos, ios_base::in);
+	      const pos_type __p = this->rdbuf()->pubseekpos(__pos,
+							     ios_base::in);
 
 	      // 129. Need error indication from seekp() and seekg()
 	      if (__p == pos_type(off_type(-1)))
@@ -903,8 +904,8 @@ namespace std
 	  if (!this->fail())
 	    {
 	      // 136.  seekp, seekg setting wrong streams?
-	      pos_type __p = this->rdbuf()->pubseekoff(__off, __dir,
-						       ios_base::in);
+	      const pos_type __p = this->rdbuf()->pubseekoff(__off, __dir,
+							     ios_base::in);
 
 	      // 129. Need error indication from seekp() and seekg()
 	      if (__p == pos_type(off_type(-1)))
@@ -924,13 +925,15 @@ namespace std
     operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c)
     {
       typedef basic_istream<_CharT, _Traits>		__istream_type;
+      typedef typename __istream_type::int_type         __int_type;
+
       typename __istream_type::sentry __cerb(__in, false);
       if (__cerb)
 	{
 	  ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 	  try
 	    {
-	      typename __istream_type::int_type __cb = __in.rdbuf()->sbumpc();
+	      const __int_type __cb = __in.rdbuf()->sbumpc();
 	      if (!_Traits::eq_int_type(__cb, _Traits::eof()))
 		__c = _Traits::to_char_type(__cb);
 	      else
@@ -1043,11 +1046,13 @@ namespace std
 	{
 	  try
 	    {
+	      // Avoid reallocation for common case.
 	      __str.erase();
-	      streamsize __w = __in.width();
-	      __size_type __n;
-	      __n = __w > 0 ? static_cast<__size_type>(__w) : __str.max_size();
-
+	      _CharT __buf[128];
+	      __size_type __len = 0;	      
+	      const streamsize __w = __in.width();
+	      const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
+		                              : __str.max_size();
 	      const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
 	      const __int_type __eof = _Traits::eof();
 	      __streambuf_type* __sb = __in.rdbuf();
@@ -1057,10 +1062,17 @@ namespace std
 		     && !_Traits::eq_int_type(__c, __eof)
 		     && !__ct.is(ctype_base::space, _Traits::to_char_type(__c)))
 		{
-		  __str += _Traits::to_char_type(__c);
+		  if (__len == sizeof(__buf) / sizeof(_CharT))
+		    {
+		      __str.append(__buf, sizeof(__buf) / sizeof(_CharT));
+		      __len = 0;
+		    }
+		  __buf[__len++] = _Traits::to_char_type(__c);
 		  ++__extracted;
 		  __c = __sb->snextc();
 		}
+	      __str.append(__buf, __len);
+
 	      if (_Traits::eq_int_type(__c, __eof))
 		__err |= ios_base::eofbit;
 	      __in.width(0);
@@ -1102,7 +1114,7 @@ namespace std
 	{
 	  try
 	    {
-	      // Avoid reallocation for common case.	      
+	      // Avoid reallocation for common case.
 	      __str.erase();
 	      _CharT __buf[128];
 	      __size_type __len = 0;

libstdc++-v3/include/bits/ostream.tcc

 // ostream classes -*- C++ -*-
 
-// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003
+// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
 // Free Software Foundation, Inc.
 //
 // This file is part of the GNU ISO C++ Library.  This library is free
@@ -129,12 +129,13 @@ namespace std
 	  try
 	    {
 	      bool __b = false;
-	      char_type __c = this->fill();
-	      ios_base::fmtflags __fmt = this->flags() & ios_base::basefield;
+	      const char_type __c = this->fill();
+	      const ios_base::fmtflags __fmt = (this->flags()
+						& ios_base::basefield);
 	      const __num_put_type& __np = __check_facet(this->_M_num_put);
 	      if ((__fmt & ios_base::oct) || (__fmt & ios_base::hex))
 		{
-		  unsigned long __l = static_cast<unsigned long>(__n);
+		  const unsigned long __l = static_cast<unsigned long>(__n);
 		  __b = __np.put(*this, *this, __c, __l).failed();
 		}
 	      else
@@ -186,13 +187,14 @@ namespace std
 	  try
 	    {
 	      bool __b = false;
-	      char_type __c = this->fill();
-	      ios_base::fmtflags __fmt = this->flags() & ios_base::basefield;
+	      const char_type __c = this->fill();
+	      const ios_base::fmtflags __fmt = (this->flags()
+						& ios_base::basefield);
 	      const __num_put_type& __np = __check_facet(this->_M_num_put);
 	      if ((__fmt & ios_base::oct) || (__fmt & ios_base::hex))
 		{
-		  unsigned long long __l;
-		  __l = static_cast<unsigned long long>(__n);
+		  const unsigned long long __l = (static_cast<
+						  unsigned long long>(__n));
 		  __b = __np.put(*this, *this, __c, __l).failed();
 		}
 	      else
@@ -342,7 +344,7 @@ namespace std
 	  ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
 	  try
 	    {
-	      int_type __put = this->rdbuf()->sputc(__c);
+	      const int_type __put = this->rdbuf()->sputc(__c);
 	      if (traits_type::eq_int_type(__put, traits_type::eof()))
 		__err |= ios_base::badbit;
 	    }
@@ -426,7 +428,8 @@ namespace std
 	    {
 	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
 	      // 136.  seekp, seekg setting wrong streams?
-	      pos_type __p = this->rdbuf()->pubseekpos(__pos, ios_base::out);
+	      const pos_type __p = this->rdbuf()->pubseekpos(__pos,
+							     ios_base::out);
 
 	      // 129. Need error indication from seekp() and seekg()
 	      if (__p == pos_type(off_type(-1)))
@@ -452,8 +455,8 @@ namespace std
 	    {
 	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
 	      // 136.  seekp, seekg setting wrong streams?
-	      pos_type __p = this->rdbuf()->pubseekoff(__off, __dir,
-						       ios_base::out);
+	      const pos_type __p = this->rdbuf()->pubseekoff(__off, __dir,
+							     ios_base::out);
 
 	      // 129. Need error indication from seekp() and seekg()
 	      if (__p == pos_type(off_type(-1)))
@@ -542,8 +545,9 @@ namespace std
 	      streamsize __len = static_cast<streamsize>(_Traits::length(__s));
 	      if (__w > __len)
 		{
-		  _CharT* __cs = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
-								       * __w));
+		  _CharT* __cs = (static_cast<
+				  _CharT*>(__builtin_alloca(sizeof(_CharT)
+							    * __w)));
 		  __pad<_CharT, _Traits>::_S_pad(__out, __out.fill(), __cs,
 						 __s, __w, __len, false);
 		  __s = __cs;
@@ -585,8 +589,9 @@ namespace std
 	      streamsize __len = static_cast<streamsize>(__clen);
 	      if (__w > __len)
 		{
-		  _CharT* __cs = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
-								       * __w));
+		  _CharT* __cs = (static_cast<
+				  _CharT*>(__builtin_alloca(sizeof(_CharT)
+							    * __w)));
 		  __pad<_CharT, _Traits>::_S_pad(__out, __out.fill(), __cs,
 						 __ws, __w, __len, false);
 		  __str = __cs;
@@ -653,7 +658,8 @@ namespace std
 	  // 25. String operator<< uses width() value wrong
 	  if (__w > __len)
 	    {
-	      _CharT* __cs = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT) * __w));
+	      _CharT* __cs = (static_cast<
+			      _CharT*>(__builtin_alloca(sizeof(_CharT) * __w)));
 	      __pad<_CharT, _Traits>::_S_pad(__out, __out.fill(), __cs, __s,
 					     __w, __len, false);
 	      __s = __cs;

libstdc++-v3/testsuite/21_strings/basic_string/inserters_extractors/char/11.cc

+// Copyright (C) 2004 Free Software Foundation
+//
+// 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.
+
+// 21.3.7.9 inserters and extractors
+
+#include <istream>
+#include <string>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+using namespace std;
+
+string prepare(string::size_type len, unsigned nchunks)
+{
+  string ret;
+  for (unsigned i = 0; i < nchunks; ++i)
+    {
+      for (string::size_type j = 0; j < len; ++j)
+	ret.push_back('a' + rand() % 26);
+      len *= 2;
+      ret.push_back(' ');
+    }
+  return ret;
+}
+
+void check(istream& stream, const string& str)
+{
+  bool test __attribute__((unused)) = true;
+
+  string chunk;
+  string::size_type index = 0, index_new = 0;
+
+  while (stream >> chunk)
+    {
+      index_new = str.find(' ', index);
+      VERIFY( !str.compare(index, index_new - index, chunk) );
+      index = index_new + 1;
+    }
+  VERIFY( stream.eof() );
+}
+
+// istream& operator>>(istream&, string&)
+void test01()
+{
+  const char filename[] = "inserters_extractors-3.txt";
+
+  const string data = prepare(666, 10);
+
+  ofstream ofstrm;
+  ofstrm.open(filename);
+  ofstrm.write(data.data(), data.size());
+  ofstrm.close();
+
+  ifstream ifstrm;
+  ifstrm.open(filename);
+  check(ifstrm, data);
+  ifstrm.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}

libstdc++-v3/testsuite/21_strings/basic_string/inserters_extractors/wchar_t/11.cc

+// Copyright (C) 2004 Free Software Foundation
+//
+// 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.
+
+// 21.3.7.9 inserters and extractors
+
+#include <istream>
+#include <string>
+#include <fstream>
+#include <testsuite_hooks.h>
+
+using namespace std;
+
+wstring prepare(wstring::size_type len, unsigned nchunks)
+{
+  wstring ret;
+  for (unsigned i = 0; i < nchunks; ++i)
+    {
+      for (wstring::size_type j = 0; j < len; ++j)
+	ret.push_back(L'a' + rand() % 26);
+      len *= 2;
+      ret.push_back(L' ');
+    }
+  return ret;
+}
+
+void check(wistream& stream, const wstring& str)
+{
+  bool test __attribute__((unused)) = true;
+
+  wstring chunk;
+  wstring::size_type index = 0, index_new = 0;
+
+  while (stream >> chunk)
+    {
+      index_new = str.find(L' ', index);
+      VERIFY( !str.compare(index, index_new - index, chunk) );
+      index = index_new + 1;
+    }
+  VERIFY( stream.eof() );
+}
+
+// istream& operator>>(istream&, string&)
+void test01()
+{
+  const char filename[] = "inserters_extractors-3.txt";
+
+  const wstring data = prepare(666, 10);
+
+  wofstream ofstrm;
+  ofstrm.open(filename);
+  ofstrm.write(data.data(), data.size());
+  ofstrm.close();
+
+  wifstream ifstrm;
+  ifstrm.open(filename);
+  check(ifstrm, data);
+  ifstrm.close();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}