This patch captures and serializes all output being written by the

command line driver, including the lldb prompt being output by
editline, the asynchronous process output & error messages, and
asynchronous messages written by target stop-hooks.

As part of this it introduces a new Stream class,
StreamAsynchronousIO.  A StreamAsynchronousIO object is created with a
broadcaster, who will eventually broadcast the stream's data for a
listener to handle, and an event type indicating what type of event
the broadcaster will broadcast.  When the Write method is called on a
StreamAsynchronousIO object, the data is appended to an internal
string.  When the Flush method is called on a StreamAsynchronousIO
object, it broadcasts it's data string and clears the string.

Anything in lldb-core that needs to generate asynchronous output for
the end-user should use the StreamAsynchronousIO objects.

I have also added a new notification type for InputReaders, to let
them know that a asynchronous output has been written. This is to
allow the input readers to, for example, refresh their prompts and
lines, if desired.  I added the case statements to all the input
readers to catch this notification, but I haven't added any code for
handling them yet (except to the IOChannel input reader).

llvm-svn: 130721

4 files changed, 76 insertions, 0 deletions

diff --git a/lldb/source/Core/Debugger.cpp b/lldb/source/Core/Debugger.cpp
index f1a64b98209..f328c626fd1 100644
--- a/lldb/source/Core/Debugger.cpp
+++ b/lldb/source/Core/Debugger.cpp
@@ -423,6 +423,20 @@ Debugger::CleanUpInputReaders ()
 }
 
 void
+Debugger::NotifyTopInputReader (InputReaderAction notification)
+{
+    InputReaderSP reader_sp (GetCurrentInputReader());
+    if (reader_sp)
+	{
+        reader_sp->Notify (notification);
+
+        // Flush out any input readers that are done.
+        while (CheckIfTopInputReaderIsDone ())
+            /* Do nothing. */;
+    }
+}
+
+void
 Debugger::WriteToDefaultReader (const char *bytes, size_t bytes_len)
 {
     if (bytes && bytes_len)
diff --git a/lldb/source/Core/Event.cpp b/lldb/source/Core/Event.cpp
index 8b0ac16e2b6..ac122858c71 100644
--- a/lldb/source/Core/Event.cpp
+++ b/lldb/source/Core/Event.cpp
@@ -198,3 +198,10 @@ EventDataBytes::GetEventDataFromEvent (const Event *event_ptr)
     return NULL;
 }
 
+void
+EventDataBytes::SwapBytes (std::string &new_bytes)
+{
+    m_bytes.swap (new_bytes);
+}
+
+
diff --git a/lldb/source/Core/InputReader.cpp b/lldb/source/Core/InputReader.cpp
index fc94bed0834..26f7f842314 100644
--- a/lldb/source/Core/InputReader.cpp
+++ b/lldb/source/Core/InputReader.cpp
@@ -327,6 +327,9 @@ InputReader::Notify (InputReaderAction notification)
         m_active = false;
         break;
     
+    case eInputReaderAsynchronousOutputWritten:
+        break;
+        
     case eInputReaderInterrupt:
     case eInputReaderEndOfFile:
         break;
diff --git a/lldb/source/Core/StreamAsynchronousIO.cpp b/lldb/source/Core/StreamAsynchronousIO.cpp
new file mode 100644
index 00000000000..84659c6e16b
--- /dev/null
+++ b/lldb/source/Core/StreamAsynchronousIO.cpp
@@ -0,0 +1,52 @@
+//===-- StreamBroadcast.cpp -------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <stdio.h>
+
+#include "lldb/lldb-private.h"
+#include "lldb/Core/Broadcaster.h"
+#include "lldb/Core/Event.h"
+#include "lldb/Core/StreamAsynchronousIO.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+
+StreamAsynchronousIO::StreamAsynchronousIO (Broadcaster &broadcaster, uint32_t broadcast_event_type) :
+    Stream (0, 4, eByteOrderBig),
+    m_broadcaster (broadcaster),
+    m_broadcast_event_type (broadcast_event_type),
+    m_accumulated_data ()
+{
+}
+
+StreamAsynchronousIO::~StreamAsynchronousIO ()
+{
+}
+
+void
+StreamAsynchronousIO::Flush ()
+{
+    if (m_accumulated_data.GetSize() > 0)
+    {
+        std::auto_ptr<EventDataBytes> data_bytes_ap (new EventDataBytes);
+        // Let's swap the bytes to avoid LARGE string copies.
+        data_bytes_ap->SwapBytes (m_accumulated_data.GetString());
+        EventSP new_event_sp (new Event (m_broadcast_event_type, data_bytes_ap.release()));
+        m_broadcaster.BroadcastEvent (new_event_sp);
+        m_accumulated_data.Clear();
+    }
+}
+
+int
+StreamAsynchronousIO::Write (const void *s, size_t length)
+{
+    m_accumulated_data.Write (s, length);
+    return length;
+}