Save and restore terminal state when lldb is suspended with SIGTSTP and resumed with SIGCONT.

Readline & gdb have a bunch of code to handle older UNIX'es with other job control mechanisms.
I didn't try to replicate that.

llvm-svn: 169032

7 files changed, 80 insertions, 2 deletions

diff --git a/lldb/include/lldb/API/SBDebugger.h b/lldb/include/lldb/API/SBDebugger.h
index 41bcfa5068c..2de86d6a8ca 100644
--- a/lldb/include/lldb/API/SBDebugger.h
+++ b/lldb/include/lldb/API/SBDebugger.h
@@ -78,7 +78,7 @@ public:
 
     void
     SetErrorFileHandle (FILE *f, bool transfer_ownership);
-
+    
     FILE *
     GetInputFileHandle ();
 
@@ -88,6 +88,12 @@ public:
     FILE *
     GetErrorFileHandle ();
 
+    void
+    SaveInputTerminalState();
+    
+    void
+    RestoreInputTerminalState();
+
     lldb::SBCommandInterpreter
     GetCommandInterpreter ();
 
diff --git a/lldb/include/lldb/Core/Debugger.h b/lldb/include/lldb/Core/Debugger.h
index 67fa370caaa..f47153b00c8 100644
--- a/lldb/include/lldb/Core/Debugger.h
+++ b/lldb/include/lldb/Core/Debugger.h
@@ -116,6 +116,12 @@ public:
 
     void
     SetErrorFileHandle (FILE *fh, bool tranfer_ownership);
+    
+    void
+    SaveInputTerminalState();
+    
+    void
+    RestoreInputTerminalState();
 
     Stream&
     GetOutputStream ()
@@ -351,6 +357,7 @@ protected:
     StreamFile m_input_file;
     StreamFile m_output_file;
     StreamFile m_error_file;
+    TerminalState m_terminal_state;
     TargetList m_target_list;
     PlatformList m_platform_list;
     Listener m_listener;
diff --git a/lldb/include/lldb/Host/Terminal.h b/lldb/include/lldb/Host/Terminal.h
index dfa345182d7..201f07a8a5e 100644
--- a/lldb/include/lldb/Host/Terminal.h
+++ b/lldb/include/lldb/Host/Terminal.h
@@ -132,6 +132,9 @@ public:
     //------------------------------------------------------------------
     bool
     IsValid() const;
+    
+    void
+    Clear ();
 
 protected:
 
diff --git a/lldb/source/API/SBDebugger.cpp b/lldb/source/API/SBDebugger.cpp
index af9447a7e18..0c957a677df 100644
--- a/lldb/source/API/SBDebugger.cpp
+++ b/lldb/source/API/SBDebugger.cpp
@@ -291,6 +291,20 @@ SBDebugger::GetErrorFileHandle ()
     return NULL;
 }
 
+void
+SBDebugger::SaveInputTerminalState()
+{
+    if (m_opaque_sp)
+        m_opaque_sp->SaveInputTerminalState();
+}
+
+void
+SBDebugger::RestoreInputTerminalState()
+{
+    if (m_opaque_sp)
+        m_opaque_sp->RestoreInputTerminalState();
+
+}
 SBCommandInterpreter
 SBDebugger::GetCommandInterpreter ()
 {
diff --git a/lldb/source/Core/Debugger.cpp b/lldb/source/Core/Debugger.cpp
index aadbf4d1da3..e817868eb7b 100644
--- a/lldb/source/Core/Debugger.cpp
+++ b/lldb/source/Core/Debugger.cpp
@@ -548,6 +548,7 @@ Debugger::Debugger (lldb::LogOutputCallback log_callback, void *baton) :
     m_input_file (),
     m_output_file (),
     m_error_file (),
+    m_terminal_state (),
     m_target_list (*this),
     m_platform_list (),
     m_listener ("lldb.Debugger"),
@@ -615,6 +616,7 @@ Debugger::Clear()
     
     // Close the input file _before_ we close the input read communications class
     // as it does NOT own the input file, our m_input_file does.
+    m_terminal_state.Clear();
     GetInputFile().Close ();
     // Now that we have closed m_input_file, we can now tell our input communication
     // class to close down. Its read thread should quickly exit after we close
@@ -662,7 +664,10 @@ Debugger::SetInputFileHandle (FILE *fh, bool tranfer_ownership)
     // want to objects trying to own and close a file descriptor.
     m_input_comm.SetConnection (new ConnectionFileDescriptor (in_file.GetDescriptor(), false));
     m_input_comm.SetReadThreadBytesReceivedCallback (Debugger::DispatchInputCallback, this);
-
+    
+    // Save away the terminal state if that is relevant, so that we can restore it in RestoreInputState.
+    SaveInputTerminalState ();
+    
     Error error;
     if (m_input_comm.StartReadThread (&error) == false)
     {
@@ -698,6 +703,20 @@ Debugger::SetErrorFileHandle (FILE *fh, bool tranfer_ownership)
         err_file.SetStream (stderr, false);
 }
 
+void
+Debugger::SaveInputTerminalState ()
+{
+    File &in_file = GetInputFile();
+    if (in_file.GetDescriptor() != File::kInvalidDescriptor)
+        m_terminal_state.Save(in_file.GetDescriptor(), true);
+}
+
+void
+Debugger::RestoreInputTerminalState ()
+{
+    m_terminal_state.Restore();
+}
+
 ExecutionContext
 Debugger::GetSelectedExecutionContext ()
 {
diff --git a/lldb/source/Host/common/Terminal.cpp b/lldb/source/Host/common/Terminal.cpp
index ce0e15fb610..89d21cf0bf6 100644
--- a/lldb/source/Host/common/Terminal.cpp
+++ b/lldb/source/Host/common/Terminal.cpp
@@ -120,6 +120,15 @@ TerminalState::~TerminalState()
 {
 }
 
+void
+TerminalState::Clear ()
+{
+    m_tty.Clear();
+    m_tflags = -1;
+    m_termios_ap.reset();
+    m_process_group = -1;
+}
+
 //----------------------------------------------------------------------
 // Save the current state of the TTY for the file descriptor "fd"
 // and if "save_process_group" is true, attempt to save the process
diff --git a/lldb/tools/driver/Driver.cpp b/lldb/tools/driver/Driver.cpp
index 85fec519f37..b410f572a6e 100644
--- a/lldb/tools/driver/Driver.cpp
+++ b/lldb/tools/driver/Driver.cpp
@@ -1579,6 +1579,24 @@ sigint_handler (int signo)
 	exit (signo);
 }
 
+void
+sigtstp_handler (int signo)
+{
+    g_driver->GetDebugger().SaveInputTerminalState();
+    signal (signo, SIG_DFL);
+    kill (getpid(), signo);
+    signal (signo, sigtstp_handler);
+}
+
+void
+sigcont_handler (int signo)
+{
+    g_driver->GetDebugger().RestoreInputTerminalState();
+    signal (signo, SIG_DFL);
+    kill (getpid(), signo);
+    signal (signo, sigcont_handler);
+}
+
 int
 main (int argc, char const *argv[], const char *envp[])
 {
@@ -1589,6 +1607,8 @@ main (int argc, char const *argv[], const char *envp[])
     signal (SIGPIPE, SIG_IGN);
     signal (SIGWINCH, sigwinch_handler);
     signal (SIGINT, sigint_handler);
+    signal (SIGTSTP, sigtstp_handler);
+    signal (SIGCONT, sigcont_handler);
 
     // Create a scope for driver so that the driver object will destroy itself
     // before SBDebugger::Terminate() is called.