sstream.tcc (seekpos): Minor rearrangement of two conditionals consistently with seekoff.

2004-10-01  Paolo Carlini  <pcarlini@suse.de>

	* include/bits/sstream.tcc (seekpos): Minor rearrangement of two
	conditionals consistently with seekoff.
	* include/std/std_sstream.h (setbuf): Avoid a string temporary.
	(_M_sync): Simplify a bit, clean-up comment.

From-SVN: r88389

libstdc++-v3/ChangeLog

+2004-10-01  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/bits/sstream.tcc (seekpos): Minor rearrangement of two
+	conditionals consistently with seekoff.
+	* include/std/std_sstream.h (setbuf): Avoid a string temporary.
+	(_M_sync): Simplify a bit, clean-up comment.
+
 2004-09-30  Paolo Carlini  <pcarlini@suse.de>
 
 	PR libstdc++/10975 (DR 453)

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

@@ -187,14 +187,14 @@ namespace std
       const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
 
       const char_type* __beg = __testin ? this->eback() : this->pbase();
-      if (__beg)
+      if (__beg && (__testin || __testout))
 	{
 	  _M_update_egptr();
 
-	  off_type __pos(__sp);
+	  const off_type __pos(__sp);
 	  const bool __testpos = 0 <= __pos
 	                         && __pos <=  this->egptr() - __beg;
-	  if ((__testin || __testout) && __testpos)
+	  if (__testpos)
 	    {
 	      if (__testin)
 		this->gbump((__beg + __pos) - this->gptr());

libstdc++-v3/include/std/std_sstream.h

@@ -219,7 +219,7 @@ namespace std
 	    // things will quickly blow up.
 	    
 	    // Step 1: Destroy the current internal array.
-	    _M_string = __string_type(__s, __n);
+	    _M_string.assign(__s, __n);
 	    
 	    // Step 2: Use the external array.
 	    _M_sync(__s, 0, 0);
@@ -253,20 +253,19 @@ namespace std
       {
 	const bool __testin = this->_M_mode & ios_base::in;
 	const bool __testout = this->_M_mode & ios_base::out;
-	const __size_type __len = _M_string.size();
+	char_type* __end = __base + _M_string.size();
 
 	if (__testin)
-	  this->setg(__base, __base + __i, __base + __len);
+	  this->setg(__base, __base + __i, __end);
 	if (__testout)
 	  {
 	    this->setp(__base, __base + _M_string.capacity());
 	    this->pbump(__o);
-	    // We need a pointer to the string end anyway, even when
-	    // !__testin: in that case, however, for the correct
-	    // functioning of the streambuf inlines all the get area
-	    // pointers must be identical.
+	    // egptr() always tracks the string end. When !__testin,
+	    // for the correct functioning of the streambuf inlines
+	    // the other get area pointers are identical.
 	    if (!__testin)
-	      this->setg(__base + __len, __base + __len, __base + __len);
+	      this->setg(__end, __end, __end);
 	  }
       }