Expanded the flags that can be set for a command object in lldb_private::CommandObject. This list of available flags are:

enum
{
    //----------------------------------------------------------------------
    // eFlagRequiresTarget
    //
    // Ensures a valid target is contained in m_exe_ctx prior to executing
    // the command. If a target doesn't exist or is invalid, the command
    // will fail and CommandObject::GetInvalidTargetDescription() will be
    // returned as the error. CommandObject subclasses can override the
    // virtual function for GetInvalidTargetDescription() to provide custom
    // strings when needed.
    //----------------------------------------------------------------------
    eFlagRequiresTarget         = (1u << 0),
    //----------------------------------------------------------------------
    // eFlagRequiresProcess
    //
    // Ensures a valid process is contained in m_exe_ctx prior to executing
    // the command. If a process doesn't exist or is invalid, the command
    // will fail and CommandObject::GetInvalidProcessDescription() will be
    // returned as the error. CommandObject subclasses can override the
    // virtual function for GetInvalidProcessDescription() to provide custom
    // strings when needed.
    //----------------------------------------------------------------------
    eFlagRequiresProcess        = (1u << 1),
    //----------------------------------------------------------------------
    // eFlagRequiresThread
    //
    // Ensures a valid thread is contained in m_exe_ctx prior to executing
    // the command. If a thread doesn't exist or is invalid, the command
    // will fail and CommandObject::GetInvalidThreadDescription() will be
    // returned as the error. CommandObject subclasses can override the
    // virtual function for GetInvalidThreadDescription() to provide custom
    // strings when needed.
    //----------------------------------------------------------------------
    eFlagRequiresThread         = (1u << 2),
    //----------------------------------------------------------------------
    // eFlagRequiresFrame
    //
    // Ensures a valid frame is contained in m_exe_ctx prior to executing
    // the command. If a frame doesn't exist or is invalid, the command
    // will fail and CommandObject::GetInvalidFrameDescription() will be
    // returned as the error. CommandObject subclasses can override the
    // virtual function for GetInvalidFrameDescription() to provide custom
    // strings when needed.
    //----------------------------------------------------------------------
    eFlagRequiresFrame          = (1u << 3),
    //----------------------------------------------------------------------
    // eFlagRequiresRegContext
    //
    // Ensures a valid register context (from the selected frame if there
    // is a frame in m_exe_ctx, or from the selected thread from m_exe_ctx)
    // is availble from m_exe_ctx prior to executing the command. If a
    // target doesn't exist or is invalid, the command will fail and
    // CommandObject::GetInvalidRegContextDescription() will be returned as
    // the error. CommandObject subclasses can override the virtual function
    // for GetInvalidRegContextDescription() to provide custom strings when
    // needed.
    //----------------------------------------------------------------------
    eFlagRequiresRegContext     = (1u << 4),
    //----------------------------------------------------------------------
    // eFlagTryTargetAPILock
    //
    // Attempts to acquire the target lock if a target is selected in the
    // command interpreter. If the command object fails to acquire the API
    // lock, the command will fail with an appropriate error message.
    //----------------------------------------------------------------------
    eFlagTryTargetAPILock       = (1u << 5),
    //----------------------------------------------------------------------
    // eFlagProcessMustBeLaunched
    //
    // Verifies that there is a launched process in m_exe_ctx, if there
    // isn't, the command will fail with an appropriate error message.
    //----------------------------------------------------------------------
    eFlagProcessMustBeLaunched  = (1u << 6),
    //----------------------------------------------------------------------
    // eFlagProcessMustBePaused
    //
    // Verifies that there is a paused process in m_exe_ctx, if there
    // isn't, the command will fail with an appropriate error message.
    //----------------------------------------------------------------------
    eFlagProcessMustBePaused    = (1u << 7)
};

Now each command object contains a "ExecutionContext m_exe_ctx;" member variable that gets initialized prior to running the command. The validity of the target objects in m_exe_ctx are checked to ensure that any target/process/thread/frame/reg context that are required are valid prior to executing the command. Each command object also contains a Mutex::Locker m_api_locker which gets used if eFlagTryTargetAPILock is set. This centralizes a lot of checking code that was previously and inconsistently implemented across many commands.

llvm-svn: 171990

1 files changed, 5 insertions, 15 deletions

diff --git a/lldb/source/Commands/CommandObjectSource.cpp b/lldb/source/Commands/CommandObjectSource.cpp
index 9915d70..576519a 100644
--- a/lldb/source/Commands/CommandObjectSource.cpp
+++ b/lldb/source/Commands/CommandObjectSource.cpp
@@ -250,7 +250,8 @@ public:
         CommandObjectParsed (interpreter,
                              "source list",
                              "Display source code (as specified) based on the current executable's debug info.",
-                             NULL),
+                             NULL,
+                             eFlagRequiresTarget), 
         m_options (interpreter)
     {
     }
@@ -307,18 +308,7 @@ protected:
             return false;
         }
 
-        ExecutionContext exe_ctx(m_interpreter.GetExecutionContext());
-        Target *target = exe_ctx.GetTargetPtr();
-
-        if (target == NULL)
-            target = m_interpreter.GetDebugger().GetSelectedTarget().get();
-            
-        if (target == NULL)
-        {
-            result.AppendError ("invalid target, create a debug target using the 'target create' command");
-            result.SetStatus (eReturnStatusFailed);
-            return false;
-        }
+        Target *target = m_exe_ctx.GetTargetPtr();
 
         SymbolContextList sc_list;
         if (!m_options.symbol_name.empty())
@@ -455,7 +445,7 @@ protected:
             {
                 const bool show_inlines = true;
                 m_breakpoint_locations.Reset (start_file, 0, show_inlines);
-                SearchFilter target_search_filter (exe_ctx.GetTargetSP());
+                SearchFilter target_search_filter (m_exe_ctx.GetTargetSP());
                 target_search_filter.Search (m_breakpoint_locations);
             }
             else
@@ -556,7 +546,7 @@ protected:
                     bool show_module = true;
                     bool show_inlined_frames = true;
                     sc.DumpStopContext(&result.GetOutputStream(),
-                                       exe_ctx.GetBestExecutionContextScope(),
+                                       m_exe_ctx.GetBestExecutionContextScope(),
                                        sc.line_entry.range.GetBaseAddress(),
                                        show_fullpaths,
                                        show_module,