[PATCH] libstdc++/6648

[Paolo Carlini]

Hi,

the below fixes this PR, which Peter (Schmid) filed a few hours ago. It 
is quite serious (too bad for 3.1.0 :-( but seems to me relatively easy 
to fix, indeed just two lines, one for istream::getline and another for 
a similar problem in istream::ignore. In a nutshell, upon __idelim 
(__delim) we consume the current char with sbumpc(), instead of trying 
also to return the next one with snextc().

I have tested it by running the testsuite, the various interactive tests 
in narrow_stream_objects.cc and the Pooma tests, which, we have learned, 
are quite sensitive to getline problems.

Ok for trunk and 3.1.1 ??

Ciao,
Paolo.

///////////////

2002-05-13  Paolo Carlini  <pcarlini@unitus.it>

        PR libstdc++/6648
        * include/bits/istream.tcc (getline, ignore):
        Upon __idelim (__delim) call sbumpc() not snextc().
        * testsuite/27_io/narrow_stream_object.cc: Add test08.

diff -urN libstdc++-v3-orig/include/bits/istream.tcc 
libstdc++-v3/include/bits/istream.tcc
--- libstdc++-v3-orig/include/bits/istream.tcc    2002-04-22 
21:10:01.000000000 +0200
+++ libstdc++-v3/include/bits/istream.tcc    2002-05-13 
22:32:43.000000000 +0200
@@ -679,7 +679,7 @@
         {
           if (__c == __idelim)
             {
-              __sb->snextc();
+              __sb->sbumpc();
               ++_M_gcount;
             }
           else
@@ -726,7 +726,7 @@
         this->setstate(ios_base::eofbit);
           else if (__c == __delim)
         {
-          __sb->snextc();
+          __sb->sbumpc();
           ++_M_gcount;
         }
         }
diff -urN libstdc++-v3-orig/testsuite/27_io/narrow_stream_objects.cc 
libstdc++-v3/testsuite/27_io/narrow_stream_objects.cc
--- libstdc++-v3-orig/testsuite/27_io/narrow_stream_objects.cc    
2002-05-03 20:22:58.000000000 +0200
+++ libstdc++-v3/testsuite/27_io/narrow_stream_objects.cc    2002-05-13 
22:37:46.000000000 +0200
@@ -175,6 +175,16 @@
   VERIFY( s == "test" );
 }
 
+// libstdc++/6648
+// Interactive test: input must terminate upon a single '\n'.
+void test08()
+{
+  bool test = true;
+  char buff[2048];
+  std::cin.getline(buff, 2048);
+  std::cin.ignore(2048, '\n');
+}
+
 int
 main()
 {
@@ -186,5 +196,6 @@
   // test05();
   // test06();
   // test07();
+  // test08();
   return 0;
 }