ChangeLogTag:Wed Jul 28 18:26:53 1999 Carlos O'Ryan <coryan@cs.wustl.edu>

6 files changed, 43 insertions, 18 deletions

diff --git a/ChangeLog-99b b/ChangeLog-99b
index 810d4d31f53..d346e40183c 100644
--- a/ChangeLog-99b
+++ b/ChangeLog-99b
@@ -1,3 +1,18 @@
+Wed Jul 28 18:26:53 1999  Carlos O'Ryan  <coryan@cs.wustl.edu>
+
+	* ace/CDR_Stream.cpp:
+	* ace/Message_Block.h:
+	* ace/Message_Block.cpp:
+	* ace/Message_Block_T.h:
+	* ace/Message_Block_T.cpp:
+	  Re-implemented the clone() method without data copies in a
+	  backwards compatible way, a new clone_nocopy() method was added
+	  so classes that inherit from Data_Block and only override
+	  clone() will work correctly.
+	  Also fixed the implementation of Locked_Data_Blocked because it
+	  is used in TAO and we need zero-copy clone() operations in that
+	  case.
+
 Wed Jul 28 16:16:27 1999  Nanbor Wang  <nanbor@cs.wustl.edu>
 
 	* ace/OS.cpp (set): Fixed a unsigned/signed conversion problem
diff --git a/ace/CDR_Stream.cpp b/ace/CDR_Stream.cpp
index 02d32631cf5..650d29cd922 100644
--- a/ace/CDR_Stream.cpp
+++ b/ace/CDR_Stream.cpp
@@ -1032,5 +1032,5 @@ ACE_InputCDR::steal_contents (void)
 void
 ACE_InputCDR::reset_contents (void)
 {
-  this->start_.data_block (this->start_.data_block ()->clone (0, 0));
+  this->start_.data_block (this->start_.data_block ()->clone_nocopy ());
 }
diff --git a/ace/Message_Block.cpp b/ace/Message_Block.cpp
index 03e2eeecafd..45756b8ce7a 100644
--- a/ace/Message_Block.cpp
+++ b/ace/Message_Block.cpp
@@ -858,12 +858,26 @@ ACE_Message_Block::duplicate (const ACE_Message_Block *mb)
 }
 
 ACE_Data_Block *
-ACE_Data_Block::clone (ACE_Message_Block::Message_Flags mask,
-                       int copy_data) const
+ACE_Data_Block::clone (ACE_Message_Block::Message_Flags mask) const
+{
+  ACE_TRACE ("ACE_Data_Block::clone");
+
+  ACE_Data_Block* nb = this->clone_nocopy (mask);
+
+  // Copy all of the payload memory into the new object.
+  ACE_OS::memcpy (nb->base_,
+                  this->base_,
+                  this->max_size_);
+
+  return nb;
+}
+
+ACE_Data_Block *
+ACE_Data_Block::clone_nocopy (ACE_Message_Block::Message_Flags mask) const
 {
   ACE_FUNCTION_TIMEPROBE(ACE_DATA_BLOCK_CLONE_ENTER);
 
-  ACE_TRACE ("ACE_Data_Block::clone");
+  ACE_TRACE ("ACE_Data_Block::clone_nocopy");
 
   // You always want to clear this one to prevent memory leaks but you
   // might add some others later.
@@ -884,13 +898,6 @@ ACE_Data_Block::clone (ACE_Message_Block::Message_Flags mask,
                                          this->data_block_allocator_),
                          0);
 
-  // Copy all of the payload memory into the new object.
-  if (copy_data)
-    {
-      ACE_OS::memcpy (nb->base_,
-                      this->base_,
-                      this->max_size_);
-    }
 
   // Set new flags minus the mask...
   nb->clr_flags (mask | always_clear);
diff --git a/ace/Message_Block.h b/ace/Message_Block.h
index bdcf2726f00..802787ed1e6 100644
--- a/ace/Message_Block.h
+++ b/ace/Message_Block.h
@@ -511,14 +511,19 @@ public:
   // Set the total amount of space in the message.  Returns 0 if
   // successful, else -1.
 
-  virtual ACE_Data_Block *clone (ACE_Message_Block::Message_Flags mask = 0,
-                                 int copy_data = 1) const;
+  virtual ACE_Data_Block *clone (ACE_Message_Block::Message_Flags mask = 0) const;
   // Return an exact "deep copy" of the message, i.e., create fresh
   // new copies of all the Data_Blocks and continuations.
   // Notice that Data_Blocks can act as "Prototypes", i.e. derived
   // classes can override this method and create instances of
   // themselves.
 
+  virtual ACE_Data_Block *clone_nocopy (ACE_Message_Block::Message_Flags mask = 0) const;
+  // As clone above, but it does not copy the contents of the buffer,
+  // i.e., create a new Data_Block of the same dynamic type, with the
+  // same allocator, locking_strategy, and with the same amount of
+  // storage available but the buffer is unitialized.
+
   ACE_Data_Block *duplicate (void);
   // Return a "shallow" copy that increments our reference count by 1.
 
diff --git a/ace/Message_Block_T.cpp b/ace/Message_Block_T.cpp
index fb55ef6238c..199293eb3ad 100644
--- a/ace/Message_Block_T.cpp
+++ b/ace/Message_Block_T.cpp
@@ -18,7 +18,7 @@ ACE_Locked_Data_Block<ACE_LOCK>::~ACE_Locked_Data_Block (void)
 }
 
 template<class L> ACE_Data_Block *
-ACE_Locked_Data_Block<L>::clone (ACE_Message_Block::Message_Flags mask) const
+ACE_Locked_Data_Block<L>::clone_nocopy (ACE_Message_Block::Message_Flags mask) const
 {
   ACE_TRACE ("ACE_Data_Block::clone");
 
@@ -40,9 +40,6 @@ ACE_Locked_Data_Block<L>::clone (ACE_Message_Block::Message_Flags mask) const
                                                    this->data_block_allocator ()),
                          0);
 
-  // Copy all of the payload memory into the new object.
-  ACE_OS::memcpy (nb->base (), this->base (), this->size ());
-
   // Set new flags minus the mask...
   nb->clr_flags (mask | always_clear);
   return nb;
diff --git a/ace/Message_Block_T.h b/ace/Message_Block_T.h
index d5a019f92ce..b86b1df96dc 100644
--- a/ace/Message_Block_T.h
+++ b/ace/Message_Block_T.h
@@ -52,9 +52,10 @@ public:
   virtual ~ACE_Locked_Data_Block (void);
   // Delete all the resources held in the message.
 
-  virtual ACE_Data_Block *clone (ACE_Message_Block::Message_Flags mask = 0) const;
+  virtual ACE_Data_Block *clone_nocopy (ACE_Message_Block::Message_Flags mask = 0) const;
   // Return an exact "deep copy" of the message, the dynamic type is
   // ACE_Locked_Data_Block<>
+  // See the documentation in Message_Block.h for details.
 
 private:
   ACE_LOCK lock_;