[LLDB] Implement interactive command interruption

The core of this change is the new CommandInterpreter::m_command_state, which
models the state transitions for interactive commands, including an
"interrupted" state transition.

In general, command interruption requires cooperation from the code executing
the command, which needs to poll for interruption requests through
CommandInterpreter::WasInterrupted().

CommandInterpreter::PrintCommandOutput() implements an optionally
interruptible printing of the command output, which for large outputs was
likely the longest blocking part.  (ex. target modules dump symtab on a
complex binary could take 10+ minutes)

patch by lemo

Differential Revision: https://reviews.llvm.org/D37923

llvm-svn: 313904

1 files changed, 8 insertions, 6 deletions

diff --git a/lldb/scripts/interface/SBCommandInterpreter.i b/lldb/scripts/interface/SBCommandInterpreter.i
index c427d38b14d..255e8ba4496 100644
--- a/lldb/scripts/interface/SBCommandInterpreter.i
+++ b/lldb/scripts/interface/SBCommandInterpreter.i
@@ -125,18 +125,18 @@ public:
     {
         eBroadcastBitThreadShouldExit       = (1 << 0),
         eBroadcastBitResetPrompt            = (1 << 1),
-        eBroadcastBitQuitCommandReceived    = (1 << 2),           // User entered quit 
+        eBroadcastBitQuitCommandReceived    = (1 << 2),           // User entered quit
         eBroadcastBitAsynchronousOutputData = (1 << 3),
         eBroadcastBitAsynchronousErrorData  = (1 << 4)
     };
 
     SBCommandInterpreter (const lldb::SBCommandInterpreter &rhs);
-    
+
     ~SBCommandInterpreter ();
 
-    static const char * 
+    static const char *
     GetArgumentTypeAsCString (const lldb::CommandArgumentType arg_type);
-    
+
     static const char *
     GetArgumentDescriptionAsCString (const lldb::CommandArgumentType arg_type);
 
@@ -181,7 +181,7 @@ public:
 
     lldb::SBProcess
     GetProcess ();
-    
+
     lldb::SBDebugger
     GetDebugger ();
 
@@ -209,10 +209,12 @@ public:
                       int match_start_point,
                       int max_return_elements,
                       lldb::SBStringList &matches);
-    
+
     bool
     IsActive ();
 
+    bool
+    WasInterrupted () const;
 };
 
 } // namespace lldb