Create a process launcher abstraction.

This implements Host::LaunchProcess for windows, and in doing so
does some minor refactor to move towards a more modular process
launching design.

The original motivation for this is that launching processes on
windows needs some very windows specific code, which would live
most appropriately in source/Host/windows somewhere.  However,
there is already some common code that all platforms use when
launching a process before delegating to the platform specific
stuff, which lives in source/Host/common/Host.cpp which would
be nice to reuse without duplicating.

This commonality has been abstracted into MonitoringProcessLauncher,
a class which abstracts out the notion of launching a process using
an arbitrary algorithm, and then monitoring it for state changes.

The windows specific launching code lives in ProcessLauncherWindows,
and the posix specific launching code lives in ProcessLauncherPosix.
When launching a process MonitoringProcessLauncher is created, and
then an appropriate delegate launcher is created and given to the
MonitoringProcessLauncher.

Reviewed by: Greg Clayton
Differential Revision: http://reviews.llvm.org/D5781

llvm-svn: 219731

23 files changed, 488 insertions, 190 deletions

diff --git a/lldb/include/lldb/Host/Host.h b/lldb/include/lldb/Host/Host.h
index 0ebd494864c..6479f1048b8 100644
--- a/lldb/include/lldb/Host/Host.h
+++ b/lldb/include/lldb/Host/Host.h
@@ -236,11 +236,9 @@ public:
     GetProcessInfo (lldb::pid_t pid, ProcessInstanceInfo &proc_info);
 
 #if defined (__APPLE__) || defined (__linux__) || defined (__FreeBSD__) || defined (__GLIBC__) || defined (__NetBSD__)
-    static short
-    GetPosixspawnFlags (ProcessLaunchInfo &launch_info);
+    static short GetPosixspawnFlags(const ProcessLaunchInfo &launch_info);
 
-    static Error
-    LaunchProcessPosixSpawn (const char *exe_path, ProcessLaunchInfo &launch_info, ::pid_t &pid);
+    static Error LaunchProcessPosixSpawn(const char *exe_path, const ProcessLaunchInfo &launch_info, lldb::pid_t &pid);
 
     static bool AddPosixSpawnFileAction(void *file_actions, const FileAction *info, Log *log, Error &error);
 #endif
diff --git a/lldb/include/lldb/Host/HostNativeProcessBase.h b/lldb/include/lldb/Host/HostNativeProcessBase.h
index f19984dcc10..1eb5a5f92d3 100644
--- a/lldb/include/lldb/Host/HostNativeProcessBase.h
+++ b/lldb/include/lldb/Host/HostNativeProcessBase.h
@@ -11,18 +11,24 @@
 #define lldb_Host_HostNativeProcessBase_h_
 
 #include "lldb/Core/Error.h"
+#include "lldb/Host/HostProcess.h"
 #include "lldb/lldb-defines.h"
 #include "lldb/lldb-types.h"
 
 namespace lldb_private
 {
 
+class HostThread;
+
 class HostNativeProcessBase
 {
     DISALLOW_COPY_AND_ASSIGN(HostNativeProcessBase);
 
   public:
-    HostNativeProcessBase() {}
+    HostNativeProcessBase()
+        : m_process(LLDB_INVALID_PROCESS)
+    {
+    }
     explicit HostNativeProcessBase(lldb::process_t process)
         : m_process(process)
     {}
@@ -34,6 +40,8 @@ class HostNativeProcessBase
     virtual lldb::pid_t GetProcessId() const = 0;
     virtual bool IsRunning() const = 0;
 
+    virtual HostThread StartMonitoring(HostProcess::MonitorCallback callback, void *callback_baton, bool monitor_signals) = 0;
+
   protected:
     lldb::process_t m_process;
 };
diff --git a/lldb/include/lldb/Host/HostProcess.h b/lldb/include/lldb/Host/HostProcess.h
index 668dca46cc4..aff779aee21 100644
--- a/lldb/include/lldb/Host/HostProcess.h
+++ b/lldb/include/lldb/Host/HostProcess.h
@@ -32,10 +32,13 @@ namespace lldb_private
 {
 
 class HostNativeProcessBase;
+class HostThread;
 
 class HostProcess
 {
   public:
+    typedef bool (*MonitorCallback)(void *callback_baton, lldb::pid_t process, bool exited, int signal, int status);
+
     HostProcess();
     HostProcess(lldb::process_t process);
     ~HostProcess();
@@ -46,6 +49,8 @@ class HostProcess
     lldb::pid_t GetProcessId() const;
     bool IsRunning() const;
 
+    HostThread StartMonitoring(MonitorCallback callback, void *callback_baton, bool monitor_signals);
+
     HostNativeProcessBase &GetNativeProcess();
     const HostNativeProcessBase &GetNativeProcess() const;
 
diff --git a/lldb/include/lldb/Host/MonitoringProcessLauncher.h b/lldb/include/lldb/Host/MonitoringProcessLauncher.h
new file mode 100644
index 00000000000..3c3e66108f8
--- /dev/null
+++ b/lldb/include/lldb/Host/MonitoringProcessLauncher.h
@@ -0,0 +1,30 @@
+//===-- MonitoringProcessLauncher.h -----------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef lldb_Host_MonitoringProcessLauncher_h_
+#define lldb_Host_MonitoringProcessLauncher_h_
+
+#include "lldb/Host/ProcessLauncher.h"
+
+namespace lldb_private
+{
+
+class MonitoringProcessLauncher : public ProcessLauncher
+{
+  public:
+    explicit MonitoringProcessLauncher(std::unique_ptr<ProcessLauncher> delegate_launcher);
+
+    virtual HostProcess LaunchProcess(const ProcessLaunchInfo &launch_info, Error &error);
+
+  private:
+    std::unique_ptr<ProcessLauncher> m_delegate_launcher;
+};
+}
+
+#endif
diff --git a/lldb/include/lldb/Host/ProcessLauncher.h b/lldb/include/lldb/Host/ProcessLauncher.h
new file mode 100644
index 00000000000..14685fd3c53
--- /dev/null
+++ b/lldb/include/lldb/Host/ProcessLauncher.h
@@ -0,0 +1,28 @@
+//===-- ProcessLauncher.h ---------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef lldb_Host_ProcessLauncher_h_
+#define lldb_Host_ProcessLauncher_h_
+
+namespace lldb_private
+{
+
+class ProcessLaunchInfo;
+class Error;
+class HostProcess;
+
+class ProcessLauncher
+{
+  public:
+    virtual ~ProcessLauncher() {}
+    virtual HostProcess LaunchProcess(const ProcessLaunchInfo &launch_info, Error &error) = 0;
+};
+}
+
+#endif
diff --git a/lldb/include/lldb/Host/posix/HostProcessPosix.h b/lldb/include/lldb/Host/posix/HostProcessPosix.h
index f8a6bb09d2b..8c1b0599e11 100644
--- a/lldb/include/lldb/Host/posix/HostProcessPosix.h
+++ b/lldb/include/lldb/Host/posix/HostProcessPosix.h
@@ -34,6 +34,8 @@ class HostProcessPosix : public HostNativeProcessBase
 
     virtual lldb::pid_t GetProcessId() const;
     virtual bool IsRunning() const;
+
+    virtual HostThread StartMonitoring(HostProcess::MonitorCallback callback, void *callback_baton, bool monitor_signals);
 };
 }
 
diff --git a/lldb/include/lldb/Host/posix/ProcessLauncherPosix.h b/lldb/include/lldb/Host/posix/ProcessLauncherPosix.h
new file mode 100644
index 00000000000..c0e2a36e4e5
--- /dev/null
+++ b/lldb/include/lldb/Host/posix/ProcessLauncherPosix.h
@@ -0,0 +1,25 @@
+//===-- ProcessLauncherPosix.h ----------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef lldb_Host_posix_ProcessLauncherPosix_h_
+#define lldb_Host_posix_ProcessLauncherPosix_h_
+
+#include "lldb/Host/ProcessLauncher.h"
+
+namespace lldb_private
+{
+
+class ProcessLauncherPosix : public ProcessLauncher
+{
+  public:
+    virtual HostProcess LaunchProcess(const ProcessLaunchInfo &launch_info, Error &error);
+};
+}
+
+#endif
diff --git a/lldb/include/lldb/Host/windows/HostProcessWindows.h b/lldb/include/lldb/Host/windows/HostProcessWindows.h
index a970e259465..602ee11866a 100644
--- a/lldb/include/lldb/Host/windows/HostProcessWindows.h
+++ b/lldb/include/lldb/Host/windows/HostProcessWindows.h
@@ -11,6 +11,7 @@
 #define lldb_Host_HostProcessWindows_h_
 
 #include "lldb/Host/HostNativeProcessBase.h"
+#include "lldb/lldb-types.h"
 
 namespace lldb_private
 {
@@ -30,7 +31,11 @@ class HostProcessWindows : public HostNativeProcessBase
     virtual lldb::pid_t GetProcessId() const;
     virtual bool IsRunning() const;
 
+    virtual HostThread StartMonitoring(HostProcess::MonitorCallback callback, void *callback_baton, bool monitor_signals);
+
   private:
+    static lldb::thread_result_t MonitorThread(void *thread_arg);
+
     void Close();
 };
 }
diff --git a/lldb/include/lldb/Host/windows/ProcessLauncherWindows.h b/lldb/include/lldb/Host/windows/ProcessLauncherWindows.h
new file mode 100644
index 00000000000..a2fe665dcfa
--- /dev/null
+++ b/lldb/include/lldb/Host/windows/ProcessLauncherWindows.h
@@ -0,0 +1,31 @@
+//===-- ProcessLauncherWindows.h --------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef lldb_Host_windows_ProcessLauncherWindows_h_
+#define lldb_Host_windows_ProcessLauncherWindows_h_
+
+#include "lldb/Host/ProcessLauncher.h"
+#include "lldb/Host/windows/windows.h"
+
+namespace lldb_private
+{
+
+class ProcessLaunchInfo;
+
+class ProcessLauncherWindows : public ProcessLauncher
+{
+  public:
+    virtual HostProcess LaunchProcess(const ProcessLaunchInfo &launch_info, Error &error);
+
+  protected:
+    HANDLE GetStdioHandle(const ProcessLaunchInfo &launch_info, int fd);
+};
+}
+
+#endif
diff --git a/lldb/include/lldb/Target/ProcessLaunchInfo.h b/lldb/include/lldb/Target/ProcessLaunchInfo.h
index ccccc8af807..37752c34418 100644
--- a/lldb/include/lldb/Target/ProcessLaunchInfo.h
+++ b/lldb/include/lldb/Target/ProcessLaunchInfo.h
@@ -124,7 +124,7 @@ namespace lldb_private
         }
 
         bool
-        GetLaunchInSeparateProcessGroup ()
+        GetLaunchInSeparateProcessGroup() const
         {
             return m_flags.Test(lldb::eLaunchFlagLaunchInSeparateProcessGroup);
         }
@@ -148,17 +148,23 @@ namespace lldb_private
                                    bool monitor_signals);
 
         Host::MonitorChildProcessCallback
-        GetMonitorProcessCallback ()
+        GetMonitorProcessCallback() const
         {
             return m_monitor_callback;
         }
 
-        const void*
-        GetMonitorProcessBaton () const
+        void *
+        GetMonitorProcessBaton() const
         {
             return m_monitor_callback_baton;
         }
 
+        bool
+        GetMonitorSignals() const
+        {
+            return m_monitor_signals;
+        }
+
         // If the LaunchInfo has a monitor callback, then arrange to monitor the process.
         // Return true if the LaunchInfo has taken care of monitoring the process, and false if the
         // caller might want to monitor the process themselves.
diff --git a/lldb/include/lldb/lldb-defines.h b/lldb/include/lldb/lldb-defines.h
index f8028c79323..a6caf4228da 100644
--- a/lldb/include/lldb/lldb-defines.h
+++ b/lldb/include/lldb/lldb-defines.h
@@ -49,7 +49,11 @@
 // LLDB defines
 //----------------------------------------------------------------------
 #define LLDB_GENERIC_ERROR              UINT32_MAX
+#if defined(_WIN32)
+#define LLDB_DEFAULT_SHELL              "cmd.exe"
+#else
 #define LLDB_DEFAULT_SHELL              "/bin/sh"
+#endif
 
 //----------------------------------------------------------------------
 // Breakpoints
diff --git a/lldb/include/lldb/lldb-types.h b/lldb/include/lldb/lldb-types.h
index 7d4471ced52..fe902073698 100644
--- a/lldb/include/lldb/lldb-types.h
+++ b/lldb/include/lldb/lldb-types.h
@@ -95,6 +95,7 @@ namespace lldb
     typedef bool                (*ExpressionCancelCallback) (ExpressionEvaluationPhase phase, void *baton);
 }
 
+#define LLDB_INVALID_PROCESS             ((lldb::process_t)-1)
 #define LLDB_INVALID_HOST_THREAD         ((lldb::thread_t)NULL)
 #define IS_VALID_LLDB_HOST_THREAD(t)     ((t) != LLDB_INVALID_HOST_THREAD)
 
diff --git a/lldb/source/Host/CMakeLists.txt b/lldb/source/Host/CMakeLists.txt
index 73da2a890af..85211f9f017 100644
--- a/lldb/source/Host/CMakeLists.txt
+++ b/lldb/source/Host/CMakeLists.txt
@@ -16,6 +16,7 @@ add_host_subdirectory(common
   common/HostThread.cpp
   common/IOObject.cpp
   common/Mutex.cpp
+  common/MonitoringProcessLauncher.cpp
   common/NativeBreakpoint.cpp
   common/NativeBreakpointList.cpp
   common/NativeProcessProtocol.cpp
@@ -48,6 +49,7 @@ if (CMAKE_SYSTEM_NAME MATCHES "Windows")
     windows/HostThreadWindows.cpp
     windows/Mutex.cpp
     windows/PipeWindows.cpp
+    windows/ProcessLauncherWindows.cpp
     windows/ProcessRunLock.cpp
     windows/ThisThread.cpp
     windows/Windows.cpp
@@ -59,6 +61,7 @@ else()
     posix/HostProcessPosix.cpp
     posix/HostThreadPosix.cpp
     posix/PipePosix.cpp
+    posix/ProcessLauncherPosix.cpp
     )
 
   if (CMAKE_SYSTEM_NAME MATCHES "Darwin")
diff --git a/lldb/source/Host/common/Host.cpp b/lldb/source/Host/common/Host.cpp
index 09376d2d443..ee0cb197105 100644
--- a/lldb/source/Host/common/Host.cpp
+++ b/lldb/source/Host/common/Host.cpp
@@ -71,7 +71,10 @@
 #include "lldb/Host/Endian.h"
 #include "lldb/Host/FileSpec.h"
 #include "lldb/Host/FileSystem.h"
+#include "lldb/Host/HostProcess.h"
+#include "lldb/Host/MonitoringProcessLauncher.h"
 #include "lldb/Host/Mutex.h"
+#include "lldb/Host/ProcessLauncher.h"
 #include "lldb/Host/ThreadLauncher.h"
 #include "lldb/lldb-private-forward.h"
 #include "lldb/Target/FileAction.h"
@@ -86,6 +89,12 @@
 #include "llvm/Support/Path.h"
 #include "llvm/Support/raw_ostream.h"
 
+#if defined(_WIN32)
+#include "lldb/Host/windows/ProcessLauncherWindows.h"
+#else
+#include "lldb/Host/posix/ProcessLauncherPosix.h"
+#endif
+
 #if defined (__APPLE__)
 #ifndef _POSIX_SPAWN_DISABLE_ASLR
 #define _POSIX_SPAWN_DISABLE_ASLR       0x0100
@@ -717,7 +726,7 @@ Host::RunShellCommand (const char *command,
 // common/Host.cpp.
 
 short
-Host::GetPosixspawnFlags (ProcessLaunchInfo &launch_info)
+Host::GetPosixspawnFlags(const ProcessLaunchInfo &launch_info)
 {
 #ifndef __ANDROID__
     short flags = POSIX_SPAWN_SETSIGDEF | POSIX_SPAWN_SETSIGMASK;
@@ -769,7 +778,7 @@ Host::GetPosixspawnFlags (ProcessLaunchInfo &launch_info)
 }
 
 Error
-Host::LaunchProcessPosixSpawn (const char *exe_path, ProcessLaunchInfo &launch_info, ::pid_t &pid)
+Host::LaunchProcessPosixSpawn(const char *exe_path, const ProcessLaunchInfo &launch_info, lldb::pid_t &pid)
 {
     Error error;
 #ifndef __ANDROID__
@@ -890,6 +899,7 @@ Host::LaunchProcessPosixSpawn (const char *exe_path, ProcessLaunchInfo &launch_i
 #endif
     }
 
+    ::pid_t result_pid = LLDB_INVALID_PROCESS_ID;
     const size_t num_file_actions = launch_info.GetNumFileActions ();
     if (num_file_actions > 0)
     {
@@ -914,21 +924,13 @@ Host::LaunchProcessPosixSpawn (const char *exe_path, ProcessLaunchInfo &launch_i
             }
         }
 
-        error.SetError (::posix_spawnp (&pid,
-                                        exe_path,
-                                        &file_actions,
-                                        &attr,
-                                        argv,
-                                        envp),
-                        eErrorTypePOSIX);
+        error.SetError(::posix_spawnp(&result_pid, exe_path, &file_actions, &attr, argv, envp), eErrorTypePOSIX);
 
         if (error.Fail() || log)
         {
-            error.PutToLog(log, "::posix_spawnp ( pid => %i, path = '%s', file_actions = %p, attr = %p, argv = %p, envp = %p )",
-                           pid, exe_path, static_cast<void*>(&file_actions),
-                           static_cast<void*>(&attr),
-                           reinterpret_cast<const void*>(argv),
-                           reinterpret_cast<const void*>(envp));
+            error.PutToLog(log, "::posix_spawnp ( pid => %i, path = '%s', file_actions = %p, attr = %p, argv = %p, envp = %p )", result_pid,
+                           exe_path, static_cast<void *>(&file_actions), static_cast<void *>(&attr), reinterpret_cast<const void *>(argv),
+                           reinterpret_cast<const void *>(envp));
             if (log)
             {
                 for (int ii=0; argv[ii]; ++ii)
@@ -939,20 +941,13 @@ Host::LaunchProcessPosixSpawn (const char *exe_path, ProcessLaunchInfo &launch_i
     }
     else
     {
-        error.SetError (::posix_spawnp (&pid,
-                                        exe_path,
-                                        NULL,
-                                        &attr,
-                                        argv,
-                                        envp),
-                        eErrorTypePOSIX);
+        error.SetError(::posix_spawnp(&result_pid, exe_path, NULL, &attr, argv, envp), eErrorTypePOSIX);
 
         if (error.Fail() || log)
         {
             error.PutToLog(log, "::posix_spawnp ( pid => %i, path = '%s', file_actions = NULL, attr = %p, argv = %p, envp = %p )",
-                           pid, exe_path, static_cast<void*>(&attr),
-                           reinterpret_cast<const void*>(argv),
-                           reinterpret_cast<const void*>(envp));
+                           result_pid, exe_path, static_cast<void *>(&attr), reinterpret_cast<const void *>(argv),
+                           reinterpret_cast<const void *>(envp));
             if (log)
             {
                 for (int ii=0; argv[ii]; ++ii)
@@ -960,6 +955,7 @@ Host::LaunchProcessPosixSpawn (const char *exe_path, ProcessLaunchInfo &launch_i
             }
         }
     }
+    pid = result_pid;
 
     if (working_dir)
     {
@@ -1056,86 +1052,28 @@ Host::AddPosixSpawnFileAction(void *_file_actions, const FileAction *info, Log *
 
 #endif // LaunchProcedssPosixSpawn: Apple, Linux, FreeBSD and other GLIBC systems
 
-
-#if defined(__linux__) || defined(__FreeBSD__) || defined(__GLIBC__) || defined(__NetBSD__)
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__GLIBC__) || defined(__NetBSD__) || defined(_WIN32)
 // The functions below implement process launching via posix_spawn() for Linux,
 // FreeBSD and NetBSD.
 
 Error
 Host::LaunchProcess (ProcessLaunchInfo &launch_info)
 {
-    Error error;
-    char exe_path[PATH_MAX];
-
-    PlatformSP host_platform_sp (Platform::GetHostPlatform ());
-
-    const ArchSpec &arch_spec = launch_info.GetArchitecture();
-
-    FileSpec exe_spec(launch_info.GetExecutableFile());
-
-    FileSpec::FileType file_type = exe_spec.GetFileType();
-    if (file_type != FileSpec::eFileTypeRegular)
-    {
-        lldb::ModuleSP exe_module_sp;
-        error = host_platform_sp->ResolveExecutable (exe_spec,
-                                                     arch_spec,
-                                                     exe_module_sp,
-                                                     NULL);
-
-        if (error.Fail())
-            return error;
-
-        if (exe_module_sp)
-            exe_spec = exe_module_sp->GetFileSpec();
-    }
-
-    if (exe_spec.Exists())
-    {
-        exe_spec.GetPath (exe_path, sizeof(exe_path));
-    }
-    else
-    {
-        launch_info.GetExecutableFile().GetPath (exe_path, sizeof(exe_path));
-        error.SetErrorStringWithFormat ("executable doesn't exist: '%s'", exe_path);
-        return error;
-    }
-
-    assert(!launch_info.GetFlags().Test (eLaunchFlagLaunchInTTY));
-
-    ::pid_t pid = LLDB_INVALID_PROCESS_ID;
-
-    error = LaunchProcessPosixSpawn(exe_path, launch_info, pid);
+    std::unique_ptr<ProcessLauncher> delegate_launcher;
+#if defined(_WIN32)
+    delegate_launcher.reset(new ProcessLauncherWindows());
+#else
+    delegate_launcher.reset(new ProcessLauncherPosix());
+#endif
+    MonitoringProcessLauncher launcher(std::move(delegate_launcher));
 
-    if (pid != LLDB_INVALID_PROCESS_ID)
-    {
-        // If all went well, then set the process ID into the launch info
-        launch_info.SetProcessID(pid);
+    Error error;
+    HostProcess process = launcher.LaunchProcess(launch_info, error);
 
-        Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
+    // TODO(zturner): It would be better if the entire HostProcess were returned instead of writing
+    // it into this structure.
+    launch_info.SetProcessID(process.GetProcessId());
 
-        // Make sure we reap any processes we spawn or we will have zombies.
-        if (!launch_info.MonitorProcess())
-        {
-            const bool monitor_signals = false;
-            StartMonitoringChildProcess (Process::SetProcessExitStatus,
-                                         NULL,
-                                         pid,
-                                         monitor_signals);
-            if (log)
-                log->PutCString ("monitored child process with default Process::SetProcessExitStatus.");
-        }
-        else
-        {
-            if (log)
-                log->PutCString ("monitored child process with user-specified process monitor.");
-        }
-    }
-    else
-    {
-        // Invalid process ID, something didn't go well
-        if (error.Success())
-            error.SetErrorString ("process launch failed for unknown reasons");
-    }
     return error;
 }
 
diff --git a/lldb/source/Host/common/HostProcess.cpp b/lldb/source/Host/common/HostProcess.cpp
index 9339d37b912..58a214693a5 100644
--- a/lldb/source/Host/common/HostProcess.cpp
+++ b/lldb/source/Host/common/HostProcess.cpp
@@ -9,6 +9,7 @@
 
 #include "lldb/Host/HostNativeProcess.h"
 #include "lldb/Host/HostProcess.h"
+#include "lldb/Host/HostThread.h"
 
 using namespace lldb;
 using namespace lldb_private;
@@ -47,6 +48,12 @@ bool HostProcess::IsRunning() const
     return m_native_process->IsRunning();
 }
 
+HostThread
+HostProcess::StartMonitoring(HostProcess::MonitorCallback callback, void *callback_baton, bool monitor_signals)
+{
+    return m_native_process->StartMonitoring(callback, callback_baton, monitor_signals);
+}
+
 HostNativeProcessBase &HostProcess::GetNativeProcess()
 {
     return *m_native_process;
diff --git a/lldb/source/Host/common/MonitoringProcessLauncher.cpp b/lldb/source/Host/common/MonitoringProcessLauncher.cpp
new file mode 100644
index 00000000000..3b0078474b0
--- /dev/null
+++ b/lldb/source/Host/common/MonitoringProcessLauncher.cpp
@@ -0,0 +1,102 @@
+//===-- ProcessLauncherWindows.cpp ------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Core/Error.h"
+#include "lldb/Core/Log.h"
+#include "lldb/Core/Module.h"
+#include "lldb/Host/HostProcess.h"
+#include "lldb/Host/MonitoringProcessLauncher.h"
+#include "lldb/Target/Platform.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/ProcessLaunchInfo.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+MonitoringProcessLauncher::MonitoringProcessLauncher(std::unique_ptr<ProcessLauncher> delegate_launcher)
+    : m_delegate_launcher(std::move(delegate_launcher))
+{
+}
+
+HostProcess
+MonitoringProcessLauncher::LaunchProcess(const ProcessLaunchInfo &launch_info, Error &error)
+{
+    ProcessLaunchInfo resolved_info(launch_info);
+
+    error.Clear();
+    char exe_path[PATH_MAX];
+
+    PlatformSP host_platform_sp(Platform::GetHostPlatform());
+
+    const ArchSpec &arch_spec = resolved_info.GetArchitecture();
+
+    FileSpec exe_spec(resolved_info.GetExecutableFile());
+
+    FileSpec::FileType file_type = exe_spec.GetFileType();
+    if (file_type != FileSpec::eFileTypeRegular)
+    {
+        lldb::ModuleSP exe_module_sp;
+        error = host_platform_sp->ResolveExecutable(exe_spec, arch_spec, exe_module_sp, NULL);
+
+        if (error.Fail())
+            return HostProcess();
+
+        if (exe_module_sp)
+            exe_spec = exe_module_sp->GetFileSpec();
+    }
+
+    if (exe_spec.Exists())
+    {
+        exe_spec.GetPath(exe_path, sizeof(exe_path));
+    }
+    else
+    {
+        resolved_info.GetExecutableFile().GetPath(exe_path, sizeof(exe_path));
+        error.SetErrorStringWithFormat("executable doesn't exist: '%s'", exe_path);
+        return HostProcess();
+    }
+
+    resolved_info.SetExecutableFile(exe_spec, false);
+    assert(!resolved_info.GetFlags().Test(eLaunchFlagLaunchInTTY));
+
+    ::pid_t pid = LLDB_INVALID_PROCESS_ID;
+
+    HostProcess process = m_delegate_launcher->LaunchProcess(resolved_info, error);
+
+    if (process.GetProcessId() != LLDB_INVALID_PROCESS_ID)
+    {
+        Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
+
+        Host::MonitorChildProcessCallback callback = launch_info.GetMonitorProcessCallback();
+
+        void *baton = nullptr;
+        bool monitor_signals = false;
+        if (callback)
+        {
+            // If the ProcessLaunchInfo specified a callback, use that.
+            baton = launch_info.GetMonitorProcessBaton();
+            monitor_signals = launch_info.GetMonitorSignals();
+        }
+        else
+        {
+            callback = Process::SetProcessExitStatus;
+        }
+
+        process.StartMonitoring(callback, baton, monitor_signals);
+        if (log)
+            log->PutCString("started monitoring child process.");
+    }
+    else
+    {
+        // Invalid process ID, something didn't go well
+        if (error.Success())
+            error.SetErrorString("process launch failed for unknown reasons");
+    }
+    return process;
+}
diff --git a/lldb/source/Host/macosx/Host.mm b/lldb/source/Host/macosx/Host.mm
index ffa4f849965..228305e0814 100644
--- a/lldb/source/Host/macosx/Host.mm
+++ b/lldb/source/Host/macosx/Host.mm
@@ -1138,7 +1138,7 @@ getXPCAuthorization (ProcessLaunchInfo &launch_info)
 #endif
 
 static Error
-LaunchProcessXPC (const char *exe_path, ProcessLaunchInfo &launch_info, ::pid_t &pid)
+LaunchProcessXPC(const char *exe_path, ProcessLaunchInfo &launch_info, lldb::pid_t &pid)
 {
 #if !NO_XPC_SERVICES
     Error error = getXPCAuthorization(launch_info);
@@ -1347,9 +1347,9 @@ Host::LaunchProcess (ProcessLaunchInfo &launch_info)
         return error;
 #endif
     }
-    
-    ::pid_t pid = LLDB_INVALID_PROCESS_ID;
-    
+
+    lldb::pid_t pid = LLDB_INVALID_PROCESS_ID;
+
     if (ShouldLaunchUsingXPC(launch_info))
     {
         error = LaunchProcessXPC(exe_path, launch_info, pid);
diff --git a/lldb/source/Host/posix/HostProcessPosix.cpp b/lldb/source/Host/posix/HostProcessPosix.cpp
index 0d9f85377dd..8e19add048e 100644
--- a/lldb/source/Host/posix/HostProcessPosix.cpp
+++ b/lldb/source/Host/posix/HostProcessPosix.cpp
@@ -1,4 +1,4 @@
-//===-- HostProcessWindows.cpp ----------------------------------*- C++ -*-===//
+//===-- HostProcessPosix.cpp ------------------------------------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -7,6 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "lldb/Host/Host.h"
 #include "lldb/Host/posix/HostProcessPosix.h"
 #include "lldb/Host/FileSystem.h"
 
@@ -107,3 +108,9 @@ bool HostProcessPosix::IsRunning() const
     Error error = Signal(0);
     return error.Success();
 }
+
+HostThread
+HostProcessPosix::StartMonitoring(HostProcess::MonitorCallback callback, void *callback_baton, bool monitor_signals)
+{
+    return Host::StartMonitoringChildProcess(callback, callback_baton, m_process, monitor_signals);
+}
diff --git a/lldb/source/Host/posix/ProcessLauncherPosix.cpp b/lldb/source/Host/posix/ProcessLauncherPosix.cpp
new file mode 100644
index 00000000000..dd5c5121a97
--- /dev/null
+++ b/lldb/source/Host/posix/ProcessLauncherPosix.cpp
@@ -0,0 +1,33 @@
+//===-- ProcessLauncherPosix.cpp --------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Host/Host.h"
+#include "lldb/Host/HostProcess.h"
+#include "lldb/Host/posix/ProcessLauncherPosix.h"
+
+#include "lldb/Target/ProcessLaunchInfo.h"
+
+#include <limits.h>
+
+using namespace lldb;
+using namespace lldb_private;
+
+HostProcess
+ProcessLauncherPosix::LaunchProcess(const ProcessLaunchInfo &launch_info, Error &error)
+{
+    lldb::pid_t pid;
+    char exe_path[PATH_MAX];
+
+    launch_info.GetExecutableFile().GetPath(exe_path, sizeof(exe_path));
+
+    // TODO(zturner): Move the code from LaunchProcessPosixSpawn to here, and make MacOSX re-use this
+    // ProcessLauncher when it wants a posix_spawn launch.
+    error = Host::LaunchProcessPosixSpawn(exe_path, launch_info, pid);
+    return HostProcess(pid);
+}
diff --git a/lldb/source/Host/windows/Host.cpp b/lldb/source/Host/windows/Host.cpp
index 4542025f6ee..4f698df16eb 100644
--- a/lldb/source/Host/windows/Host.cpp
+++ b/lldb/source/Host/windows/Host.cpp
@@ -96,14 +96,6 @@ namespace
     }
 }
 
-Error
-Host::LaunchProcess (ProcessLaunchInfo &launch_info)
-{
-    Error error;
-    assert(!"Not implemented yet!!!");
-    return error;
-}
-
 lldb::DataBufferSP
 Host::GetAuxvData(lldb_private::Process *process)
 {
diff --git a/lldb/source/Host/windows/HostProcessWindows.cpp b/lldb/source/Host/windows/HostProcessWindows.cpp
index 447f672ac77..8388e21b853 100644
--- a/lldb/source/Host/windows/HostProcessWindows.cpp
+++ b/lldb/source/Host/windows/HostProcessWindows.cpp
@@ -8,6 +8,8 @@
 //===----------------------------------------------------------------------===//
 
 #include "lldb/Host/FileSpec.h"
+#include "lldb/Host/HostThread.h"
+#include "lldb/Host/ThreadLauncher.h"
 #include "lldb/Host/windows/windows.h"
 #include "lldb/Host/windows/HostProcessWindows.h"
 
@@ -17,6 +19,16 @@
 
 using namespace lldb_private;
 
+namespace
+{
+struct MonitorInfo
+{
+    HostProcess::MonitorCallback callback;
+    void *baton;
+    HANDLE process_handle;
+};
+}
+
 HostProcessWindows::HostProcessWindows()
     : HostNativeProcessBase()
 {
@@ -61,7 +73,7 @@ Error HostProcessWindows::GetMainModule(FileSpec &file_spec) const
 
 lldb::pid_t HostProcessWindows::GetProcessId() const
 {
-    return ::GetProcessId(m_process);
+    return (m_process == LLDB_INVALID_PROCESS) ? -1 : ::GetProcessId(m_process);
 }
 
 bool HostProcessWindows::IsRunning() const
@@ -76,9 +88,42 @@ bool HostProcessWindows::IsRunning() const
     return (code == STILL_ACTIVE);
 }
 
+HostThread
+HostProcessWindows::StartMonitoring(HostProcess::MonitorCallback callback, void *callback_baton, bool monitor_signals)
+{
+    HostThread monitor_thread;
+    MonitorInfo *info = new MonitorInfo;
+    info->callback = callback;
+    info->baton = callback_baton;
+
+    // Since the life of this HostProcessWindows instance and the life of the process may be different, duplicate the handle so that
+    // the monitor thread can have ownership over its own copy of the handle.
+    HostThread result;
+    if (::DuplicateHandle(GetCurrentProcess(), m_process, GetCurrentProcess(), &info->process_handle, 0, FALSE, DUPLICATE_SAME_ACCESS))
+        result = ThreadLauncher::LaunchThread("ChildProcessMonitor", HostProcessWindows::MonitorThread, info, nullptr);
+    return result;
+}
+
+lldb::thread_result_t
+HostProcessWindows::MonitorThread(void *thread_arg)
+{
+    DWORD exit_code;
+
+    MonitorInfo *info = static_cast<MonitorInfo *>(thread_arg);
+    if (info)
+    {
+        DWORD wait_result = ::WaitForSingleObject(info->process_handle, INFINITE);
+        ::GetExitCodeProcess(info->process_handle, &exit_code);
+        info->callback(info->baton, ::GetProcessId(info->process_handle), true, 0, exit_code);
+
+        delete (info);
+    }
+    return 0;
+}
+
 void HostProcessWindows::Close()
 {
-    if (m_process != nullptr)
+    if (m_process != LLDB_INVALID_PROCESS)
         ::CloseHandle(m_process);
     m_process = nullptr;
 }
diff --git a/lldb/source/Host/windows/ProcessLauncherWindows.cpp b/lldb/source/Host/windows/ProcessLauncherWindows.cpp
new file mode 100644
index 00000000000..7a99e0944e5
--- /dev/null
+++ b/lldb/source/Host/windows/ProcessLauncherWindows.cpp
@@ -0,0 +1,94 @@
+//===-- ProcessLauncherWindows.cpp ------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Host/HostProcess.h"
+#include "lldb/Host/windows/ProcessLauncherWindows.h"
+#include "lldb/Target/ProcessLaunchInfo.h"
+
+#include <string>
+#include <vector>
+
+using namespace lldb;
+using namespace lldb_private;
+
+HostProcess
+ProcessLauncherWindows::LaunchProcess(const ProcessLaunchInfo &launch_info, Error &error)
+{
+    error.Clear();
+
+    std::string executable;
+    std::string commandLine;
+    std::vector<char> environment;
+    STARTUPINFO startupinfo = {0};
+    PROCESS_INFORMATION pi = {0};
+
+    HANDLE stdin_handle = GetStdioHandle(launch_info, STDIN_FILENO);
+    HANDLE stdout_handle = GetStdioHandle(launch_info, STDOUT_FILENO);
+    HANDLE stderr_handle = GetStdioHandle(launch_info, STDERR_FILENO);
+
+    startupinfo.cb = sizeof(startupinfo);
+    startupinfo.dwFlags |= STARTF_USESTDHANDLES;
+    startupinfo.hStdError = stderr_handle;
+    startupinfo.hStdInput = stdin_handle;
+    startupinfo.hStdOutput = stdout_handle;
+
+    executable = launch_info.GetExecutableFile().GetPath();
+    launch_info.GetArguments().GetQuotedCommandString(commandLine);
+    BOOL result = ::CreateProcessA(executable.c_str(), const_cast<char *>(commandLine.c_str()), NULL, NULL, TRUE, CREATE_NEW_CONSOLE, NULL,
+                                   launch_info.GetWorkingDirectory(), &startupinfo, &pi);
+    if (result)
+    {
+        // Do not call CloseHandle on pi.hProcess, since we want to pass that back through the HostProcess.
+        ::CloseHandle(pi.hThread);
+    }
+
+    if (stdin_handle)
+        ::CloseHandle(stdin_handle);
+    if (stdout_handle)
+        ::CloseHandle(stdout_handle);
+    if (stderr_handle)
+        ::CloseHandle(stderr_handle);
+
+    if (!result)
+        error.SetError(::GetLastError(), eErrorTypeWin32);
+    return HostProcess(pi.hProcess);
+}
+
+HANDLE
+ProcessLauncherWindows::GetStdioHandle(const ProcessLaunchInfo &launch_info, int fd)
+{
+    const FileAction *action = launch_info.GetFileActionForFD(fd);
+    if (action == nullptr)
+        return NULL;
+    SECURITY_ATTRIBUTES secattr = {0};
+    secattr.nLength = sizeof(SECURITY_ATTRIBUTES);
+    secattr.bInheritHandle = TRUE;
+
+    const char *path = action->GetPath();
+    DWORD access = 0;
+    DWORD share = FILE_SHARE_READ | FILE_SHARE_WRITE;
+    DWORD create = 0;
+    DWORD flags = 0;
+    if (fd == STDIN_FILENO)
+    {
+        access = GENERIC_READ;
+        create = OPEN_EXISTING;
+        flags = FILE_ATTRIBUTE_READONLY;
+    }
+    if (fd == STDOUT_FILENO || fd == STDERR_FILENO)
+    {
+        access = GENERIC_WRITE;
+        create = CREATE_ALWAYS;
+        if (fd == STDERR_FILENO)
+            flags = FILE_FLAG_WRITE_THROUGH;
+    }
+
+    HANDLE result = ::CreateFile(path, access, share, &secattr, create, flags, NULL);
+    return (result == INVALID_HANDLE_VALUE) ? NULL : result;
+}
diff --git a/lldb/source/Plugins/Process/Windows/ProcessWindows.cpp b/lldb/source/Plugins/Process/Windows/ProcessWindows.cpp
index de625e3c4ba..a61a4d2b909 100644
--- a/lldb/source/Plugins/Process/Windows/ProcessWindows.cpp
+++ b/lldb/source/Plugins/Process/Windows/ProcessWindows.cpp
@@ -16,6 +16,8 @@
 #include "lldb/Core/PluginManager.h"
 #include "lldb/Core/State.h"
 #include "lldb/Host/Host.h"
+#include "lldb/Host/HostProcess.h"
+#include "lldb/Host/windows/ProcessLauncherWindows.h"
 #include "lldb/Symbol/ObjectFile.h"
 #include "lldb/Target/DynamicLoader.h"
 #include "lldb/Target/FileAction.h"
@@ -26,42 +28,6 @@
 using namespace lldb;
 using namespace lldb_private;
 
-namespace
-{
-HANDLE
-GetStdioHandle(ProcessLaunchInfo &launch_info, int fd)
-{
-    const FileAction *action = launch_info.GetFileActionForFD(fd);
-    if (action == nullptr)
-        return NULL;
-    SECURITY_ATTRIBUTES secattr = {0};
-    secattr.nLength = sizeof(SECURITY_ATTRIBUTES);
-    secattr.bInheritHandle = TRUE;
-
-    const char *path = action->GetPath();
-    DWORD access = 0;
-    DWORD share = FILE_SHARE_READ | FILE_SHARE_WRITE;
-    DWORD create = 0;
-    DWORD flags = 0;
-    if (fd == STDIN_FILENO)
-    {
-        access = GENERIC_READ;
-        create = OPEN_EXISTING;
-        flags = FILE_ATTRIBUTE_READONLY;
-    }
-    if (fd == STDOUT_FILENO || fd == STDERR_FILENO)
-    {
-        access = GENERIC_WRITE;
-        create = CREATE_ALWAYS;
-        if (fd == STDERR_FILENO)
-            flags = FILE_FLAG_WRITE_THROUGH;
-    }
-
-    HANDLE result = ::CreateFile(path, access, share, &secattr, create, flags, NULL);
-    return (result == INVALID_HANDLE_VALUE) ? NULL : result;
-}
-}
-
 //------------------------------------------------------------------------------
 // Static functions.
 
@@ -123,42 +89,10 @@ Error
 ProcessWindows::DoLaunch(Module *exe_module,
                          ProcessLaunchInfo &launch_info)
 {
-    std::string executable;
-    std::string commandLine;
-    std::vector<char> environment;
-    STARTUPINFO startupinfo = {0};
-    PROCESS_INFORMATION pi = {0};
-
-    HANDLE stdin_handle = GetStdioHandle(launch_info, STDIN_FILENO);
-    HANDLE stdout_handle = GetStdioHandle(launch_info, STDOUT_FILENO);
-    HANDLE stderr_handle = GetStdioHandle(launch_info, STDERR_FILENO);
-
-    startupinfo.cb = sizeof(startupinfo);
-    startupinfo.dwFlags |= STARTF_USESTDHANDLES;
-    startupinfo.hStdError = stderr_handle;
-    startupinfo.hStdInput = stdin_handle;
-    startupinfo.hStdOutput = stdout_handle;
-
-    executable = launch_info.GetExecutableFile().GetPath();
-    launch_info.GetArguments().GetQuotedCommandString(commandLine);
-    BOOL result = ::CreateProcessA(executable.c_str(), const_cast<char *>(commandLine.c_str()), NULL, NULL, TRUE,
-                                   CREATE_NEW_CONSOLE, NULL, launch_info.GetWorkingDirectory(), &startupinfo, &pi);
-    if (result)
-    {
-        ::CloseHandle(pi.hProcess);
-        ::CloseHandle(pi.hThread);
-    }
-
-    if (stdin_handle)
-        ::CloseHandle(stdin_handle);
-    if (stdout_handle)
-        ::CloseHandle(stdout_handle);
-    if (stderr_handle)
-        ::CloseHandle(stderr_handle);
-
     Error error;
-    if (!result)
-        error.SetErrorToErrno();
+    ProcessLauncherWindows launcher;
+    HostProcess process = launcher.LaunchProcess(launch_info, error);
+    launch_info.SetProcessID(process.GetProcessId());
     return error;
 }