Add a NativeProcessProtocol Factory class

Summary:
This replaces the static functions used for creating
NativeProcessProtocol instances with a factory pattern, and modernizes
the interface of the new class in the process -- I use llvm::Expected
instead of the Status+value combo. I also move some of the common code
(like the Delegate registration into the base class). The new
arrangement has multiple benefits:
- it removes the NativeProcess*** dependency from Process/gdb-remote
  (which for example means that liblldb no longer pulls in this code).
- it enables unit testing of the GDBRemoteCommunicationServerLLGS class
  (by providing a mock Native Process).
- serves as another example on how to use the llvm::Expected class (I
  couldn't get rid of the Initialize-type functions completely here
  because of the use of shared_from_this, but that's the next thing on
  my list here)

Tests still pass on Linux and I've made sure NetBSD compiles after this.

Reviewers: zturner, eugene, krytarowski

Subscribers: srhines, lldb-commits, mgorny

Differential Revision: https://reviews.llvm.org/D33778

llvm-svn: 307390

1 files changed, 2 insertions, 7 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerCommon.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerCommon.cpp
index de2400c51ba..f53db502be9 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerCommon.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerCommon.cpp
@@ -1046,14 +1046,9 @@ GDBRemoteCommunicationServerCommon::Handle_A(StringExtractorGDBRemote &packet) {
 
   if (success) {
     m_process_launch_error = LaunchProcess();
-    if (m_process_launch_info.GetProcessID() != LLDB_INVALID_PROCESS_ID) {
+    if (m_process_launch_error.Success())
       return SendOKResponse();
-    } else {
-      Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PROCESS));
-      if (log)
-        log->Printf("LLGSPacketHandler::%s failed to launch exe: %s",
-                    __FUNCTION__, m_process_launch_error.AsCString());
-    }
+    LLDB_LOG(log, "failed to launch exe: {0}", m_process_launch_error);
   }
   return SendErrorResponse(8);
 }