2017-10-04 Petr Ovtchenkov <ptr@void-ptr.info>

	    François Dumont  <fdumont@gcc.gnu.org>

	* include/bits/streambuf_iterator.h
	(istreambuf_iterator<>::operator*()): Do not capture iterator state
	in Debug assertion.
	(istreambuf_iterator<>::operator++()): Likewise and remove _M_sbuf check.
	(istreambuf_iterator<>::operator++(int)): Likewise.
	(istreambuf_iterator<>::_M_get()): Remove _M_c assignment.
	(istreambuf_iterator<>::_S_is_eof()): New.
	(istreambuf_iterator<>::_M_at_eof()): Adapt, use latter.
	(find(istreambuf_iterator<>, istreambuf_iterator<>, _CharT)):
	Return an iterator with _M_c set to eof to capture streambuf state
	on evaluation.
	(testsuite/24_iterators/istreambuf_iterator/2.cc): Add checks.

Co-Authored-By: François Dumont <fdumont@gcc.gnu.org>
From-SVN: r253417

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 4559f79..4d371b8 100644 (file)
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,19 @@
+2017-10-04  Petr Ovtchenkov  <ptr@void-ptr.info>
+           François Dumont  <fdumont@gcc.gnu.org>
+
+       * include/bits/streambuf_iterator.h
+       (istreambuf_iterator<>::operator*()): Do not capture iterator state
+       in Debug assertion.
+       (istreambuf_iterator<>::operator++()): Likewise and remove _M_sbuf check.
+       (istreambuf_iterator<>::operator++(int)): Likewise.
+       (istreambuf_iterator<>::_M_get()): Remove _M_c assignment.
+       (istreambuf_iterator<>::_S_is_eof()): New.
+       (istreambuf_iterator<>::_M_at_eof()): Adapt, use latter.
+       (find(istreambuf_iterator<>, istreambuf_iterator<>, _CharT)):
+       Return an iterator with _M_c set to eof to capture streambuf state
+       on evaluation.
+       (testsuite/24_iterators/istreambuf_iterator/2.cc): Add checks.
+
 2017-10-03  Jakub Jelinek  <jakub@redhat.com>
 
        * include/std/charconv (__unsigned_least_t): Fix number of closing >s for

diff --git a/libstdc++-v3/include/bits/streambuf_iterator.h b/libstdc++-v3/include/bits/streambuf_iterator.h
index f0451b1..64b8cfd 100644 (file)
--- a/libstdc++-v3/include/bits/streambuf_iterator.h
+++ b/libstdc++-v3/include/bits/streambuf_iterator.h
@@ -95,7 +95,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       // NB: This implementation assumes the "end of stream" value
       // is EOF, or -1.
       mutable streambuf_type*  _M_sbuf;
-      mutable int_type         _M_c;
+      int_type                 _M_c;
 
     public:
       ///  Construct end of input stream iterator.
@@ -122,28 +122,29 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       char_type
       operator*() const
       {
+       int_type __c = _M_get();
+
 #ifdef _GLIBCXX_DEBUG_PEDANTIC
        // Dereferencing a past-the-end istreambuf_iterator is a
        // libstdc++ extension
-       __glibcxx_requires_cond(!_M_at_eof(),
+       __glibcxx_requires_cond(!_S_is_eof(__c),
                                _M_message(__gnu_debug::__msg_deref_istreambuf)
                                ._M_iterator(*this));
 #endif
-       return traits_type::to_char_type(_M_get());
+       return traits_type::to_char_type(__c);
       }
 
       /// Advance the iterator.  Calls streambuf.sbumpc().
       istreambuf_iterator&
       operator++()
       {
-       __glibcxx_requires_cond(!_M_at_eof(),
+       __glibcxx_requires_cond(_M_sbuf &&
+                               (!_S_is_eof(_M_c) || !_S_is_eof(_M_sbuf->sgetc())),
                                _M_message(__gnu_debug::__msg_inc_istreambuf)
                                ._M_iterator(*this));
-       if (_M_sbuf)
-         {
-           _M_sbuf->sbumpc();
-           _M_c = traits_type::eof();
-         }
+
+       _M_sbuf->sbumpc();
+       _M_c = traits_type::eof();
        return *this;
       }
 
@@ -151,16 +152,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       istreambuf_iterator
       operator++(int)
       {
-       __glibcxx_requires_cond(!_M_at_eof(),
+       __glibcxx_requires_cond(_M_sbuf &&
+                               (!_S_is_eof(_M_c) || !_S_is_eof(_M_sbuf->sgetc())),
                                _M_message(__gnu_debug::__msg_inc_istreambuf)
                                ._M_iterator(*this));
 
        istreambuf_iterator __old = *this;
-       if (_M_sbuf)
-         {
-           __old._M_c = _M_sbuf->sbumpc();
-           _M_c = traits_type::eof();
-         }
+       __old._M_c = _M_sbuf->sbumpc();
+       _M_c = traits_type::eof();
        return __old;
       }
 
@@ -176,26 +175,21 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       int_type
       _M_get() const
       {
-       const int_type __eof = traits_type::eof();
-       int_type __ret = __eof;
-       if (_M_sbuf)
-         {
-           if (!traits_type::eq_int_type(_M_c, __eof))
-             __ret = _M_c;
-           else if (!traits_type::eq_int_type((__ret = _M_sbuf->sgetc()),
-                                              __eof))
-             _M_c = __ret;
-           else
-             _M_sbuf = 0;
-         }
+       int_type __ret = _M_c;
+       if (_M_sbuf && _S_is_eof(__ret) && _S_is_eof(__ret = _M_sbuf->sgetc()))
+         _M_sbuf = 0;
        return __ret;
       }
 
       bool
       _M_at_eof() const
+      { return _S_is_eof(_M_get()); }
+
+      static bool
+      _S_is_eof(int_type __c)
       {
        const int_type __eof = traits_type::eof();
-       return traits_type::eq_int_type(_M_get(), __eof);
+       return traits_type::eq_int_type(__c, __eof);
       }
     };
 
@@ -373,13 +367,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       typedef typename __is_iterator_type::traits_type     traits_type;
       typedef typename __is_iterator_type::streambuf_type  streambuf_type;
       typedef typename traits_type::int_type               int_type;
+      const int_type __eof = traits_type::eof();
 
       if (__first._M_sbuf && !__last._M_sbuf)
        {
          const int_type __ival = traits_type::to_int_type(__val);
          streambuf_type* __sb = __first._M_sbuf;
          int_type __c = __sb->sgetc();
-         while (!traits_type::eq_int_type(__c, traits_type::eof())
+         while (!traits_type::eq_int_type(__c, __eof)
                 && !traits_type::eq_int_type(__c, __ival))
            {
              streamsize __n = __sb->egptr() - __sb->gptr();
@@ -396,11 +391,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
                __c = __sb->snextc();
            }
 
-         if (!traits_type::eq_int_type(__c, traits_type::eof()))
-           __first._M_c = __c;
-         else
-           __first._M_sbuf = 0;
+         __first._M_c = __eof;
        }
+
       return __first;
     }
 

diff --git a/libstdc++-v3/testsuite/24_iterators/istreambuf_iterator/2.cc b/libstdc++-v3/testsuite/24_iterators/istreambuf_iterator/2.cc
index b81f4d4..572ea9f 100644 (file)
--- a/libstdc++-v3/testsuite/24_iterators/istreambuf_iterator/2.cc
+++ b/libstdc++-v3/testsuite/24_iterators/istreambuf_iterator/2.cc
@@ -25,9 +25,7 @@
 
 void test02(void)
 {
-
   typedef std::istreambuf_iterator<char> cistreambuf_iter;
-  typedef cistreambuf_iter::streambuf_type cstreambuf_type;
   const char slit01[] = "playa hermosa, liberia, guanacaste";
   std::string str01(slit01);
   std::istringstream istrs00(str01);
@@ -35,10 +33,14 @@ void test02(void)
 
   // ctor sanity checks
   cistreambuf_iter istrb_it01(istrs00);
-  cistreambuf_iter istrb_it02;
-  std::string tmp(istrb_it01, istrb_it02); 
+  cistreambuf_iter istrb_eos;
+  VERIFY( istrb_it01 != istrb_eos );
+
+  std::string tmp(istrb_it01, istrb_eos);
   VERIFY( tmp == str01 );
 
+  VERIFY( istrb_it01 == istrb_eos );
+
   cistreambuf_iter istrb_it03(0);
   cistreambuf_iter istrb_it04;
   VERIFY( istrb_it03 == istrb_it04 );