From e81ba283131cf76ae62fa9b601a24d080578efaa Mon Sep 17 00:00:00 2001 From: Siger Yang Date: Sun, 4 Jul 2021 19:38:12 -0300 Subject: [PATCH] [lldb/lua] Add scripted watchpoints for Lua Add support for Lua scripted watchpoints, with basic tests. Differential Revision: https://reviews.llvm.org/D105034 --- lldb/bindings/lua/lua-swigsafecast.swig | 6 ++ lldb/bindings/lua/lua-wrapper.swig | 35 ++++++++++ lldb/source/Plugins/ScriptInterpreter/Lua/Lua.cpp | 29 ++++++++ lldb/source/Plugins/ScriptInterpreter/Lua/Lua.h | 4 ++ .../ScriptInterpreter/Lua/ScriptInterpreterLua.cpp | 77 ++++++++++++++++++++-- .../ScriptInterpreter/Lua/ScriptInterpreterLua.h | 16 +++++ .../ScriptInterpreter/Lua/watchpoint_callback.test | 30 ++++++++- lldb/unittests/ScriptInterpreter/Lua/LuaTests.cpp | 5 ++ 8 files changed, 194 insertions(+), 8 deletions(-) diff --git a/lldb/bindings/lua/lua-swigsafecast.swig b/lldb/bindings/lua/lua-swigsafecast.swig index a3ed372..0b67c41 100644 --- a/lldb/bindings/lua/lua-swigsafecast.swig +++ b/lldb/bindings/lua/lua-swigsafecast.swig @@ -15,6 +15,12 @@ PushSBClass (lua_State* L, lldb::SBBreakpointLocation* breakpoint_location_sb) } void +PushSBClass (lua_State* L, lldb::SBWatchpoint* watchpoint_sb) +{ + SWIG_NewPointerObj(L, watchpoint_sb, SWIGTYPE_p_lldb__SBWatchpoint, 0); +} + +void PushSBClass (lua_State* L, lldb::SBStructuredData* structured_data_sb) { SWIG_NewPointerObj(L, structured_data_sb, SWIGTYPE_p_lldb__SBStructuredData, 0); diff --git a/lldb/bindings/lua/lua-wrapper.swig b/lldb/bindings/lua/lua-wrapper.swig index 90c2292..e070bae 100644 --- a/lldb/bindings/lua/lua-wrapper.swig +++ b/lldb/bindings/lua/lua-wrapper.swig @@ -53,5 +53,40 @@ LLDBSwigLuaBreakpointCallbackFunction return stop; } +// This function is called from Lua::CallWatchpointCallback +SWIGEXPORT llvm::Expected +LLDBSwigLuaWatchpointCallbackFunction +( + lua_State *L, + lldb::StackFrameSP stop_frame_sp, + lldb::WatchpointSP wp_sp +) +{ + lldb::SBFrame sb_frame(stop_frame_sp); + lldb::SBWatchpoint sb_wp(wp_sp); + int nargs = 2; + + // Push the Lua wrappers + PushSBClass(L, &sb_frame); + PushSBClass(L, &sb_wp); + + // Call into the Lua callback passing 'sb_frame' and 'sb_wp'. + // Expects a boolean return. + if (lua_pcall(L, nargs, 1, 0) != LUA_OK) { + llvm::Error E = llvm::make_error( + llvm::formatv("{0}\n", lua_tostring(L, -1)), + llvm::inconvertibleErrorCode()); + // Pop error message from the stack. + lua_pop(L, 1); + return std::move(E); + } + + // Boolean return from the callback + bool stop = lua_toboolean(L, -1); + lua_pop(L, 1); + + return stop; +} + %} diff --git a/lldb/source/Plugins/ScriptInterpreter/Lua/Lua.cpp b/lldb/source/Plugins/ScriptInterpreter/Lua/Lua.cpp index f14e273..e99b7b8 100644 --- a/lldb/source/Plugins/ScriptInterpreter/Lua/Lua.cpp +++ b/lldb/source/Plugins/ScriptInterpreter/Lua/Lua.cpp @@ -30,6 +30,9 @@ extern "C" llvm::Expected LLDBSwigLuaBreakpointCallbackFunction( lua_State *L, lldb::StackFrameSP stop_frame_sp, lldb::BreakpointLocationSP bp_loc_sp, StructuredDataImpl *extra_args_impl); +extern "C" llvm::Expected LLDBSwigLuaWatchpointCallbackFunction( + lua_State *L, lldb::StackFrameSP stop_frame_sp, lldb::WatchpointSP wp_sp); + #if _MSC_VER #pragma warning (pop) #endif @@ -113,6 +116,32 @@ Lua::CallBreakpointCallback(void *baton, lldb::StackFrameSP stop_frame_sp, bp_loc_sp, extra_args_impl); } +llvm::Error Lua::RegisterWatchpointCallback(void *baton, const char *body) { + lua_pushlightuserdata(m_lua_state, baton); + const char *fmt_str = "return function(frame, wp, ...) {0} end"; + std::string func_str = llvm::formatv(fmt_str, body).str(); + if (luaL_dostring(m_lua_state, func_str.c_str()) != LUA_OK) { + llvm::Error e = llvm::make_error( + llvm::formatv("{0}", lua_tostring(m_lua_state, -1)), + llvm::inconvertibleErrorCode()); + // Pop error message from the stack. + lua_pop(m_lua_state, 2); + return e; + } + lua_settable(m_lua_state, LUA_REGISTRYINDEX); + return llvm::Error::success(); +} + +llvm::Expected +Lua::CallWatchpointCallback(void *baton, lldb::StackFrameSP stop_frame_sp, + lldb::WatchpointSP wp_sp) { + + lua_pushlightuserdata(m_lua_state, baton); + lua_gettable(m_lua_state, LUA_REGISTRYINDEX); + return LLDBSwigLuaWatchpointCallbackFunction(m_lua_state, stop_frame_sp, + wp_sp); +} + llvm::Error Lua::CheckSyntax(llvm::StringRef buffer) { int error = luaL_loadbuffer(m_lua_state, buffer.data(), buffer.size(), "buffer"); diff --git a/lldb/source/Plugins/ScriptInterpreter/Lua/Lua.h b/lldb/source/Plugins/ScriptInterpreter/Lua/Lua.h index 873440f..5daedf8 100644 --- a/lldb/source/Plugins/ScriptInterpreter/Lua/Lua.h +++ b/lldb/source/Plugins/ScriptInterpreter/Lua/Lua.h @@ -37,6 +37,10 @@ public: CallBreakpointCallback(void *baton, lldb::StackFrameSP stop_frame_sp, lldb::BreakpointLocationSP bp_loc_sp, StructuredData::ObjectSP extra_args_sp); + llvm::Error RegisterWatchpointCallback(void *baton, const char *body); + llvm::Expected CallWatchpointCallback(void *baton, + lldb::StackFrameSP stop_frame_sp, + lldb::WatchpointSP wp_sp); llvm::Error LoadModule(llvm::StringRef filename); llvm::Error CheckSyntax(llvm::StringRef buffer); llvm::Error ChangeIO(FILE *out, FILE *err); diff --git a/lldb/source/Plugins/ScriptInterpreter/Lua/ScriptInterpreterLua.cpp b/lldb/source/Plugins/ScriptInterpreter/Lua/ScriptInterpreterLua.cpp index fe3dcb3..2105f4a 100644 --- a/lldb/source/Plugins/ScriptInterpreter/Lua/ScriptInterpreterLua.cpp +++ b/lldb/source/Plugins/ScriptInterpreter/Lua/ScriptInterpreterLua.cpp @@ -58,7 +58,13 @@ public: const char *instructions = nullptr; switch (m_active_io_handler) { case eIOHandlerNone: + break; case eIOHandlerWatchpoint: + instructions = "Enter your Lua command(s). Type 'quit' to end.\n" + "The commands are compiled as the body of the following " + "Lua function\n" + "function (frame, wp) end\n"; + SetPrompt(llvm::StringRef("..> ")); break; case eIOHandlerBreakpoint: instructions = "Enter your Lua command(s). Type 'quit' to end.\n" @@ -78,7 +84,8 @@ public: StringList &lines) override { size_t last = lines.GetSize() - 1; if (IsQuitCommand(lines.GetStringAtIndex(last))) { - if (m_active_io_handler == eIOHandlerBreakpoint) + if (m_active_io_handler == eIOHandlerBreakpoint || + m_active_io_handler == eIOHandlerWatchpoint) lines.DeleteStringAtIndex(last); return true; } @@ -90,8 +97,9 @@ public: // Lua always errors out to incomplete code with '' return error_str.find("") == std::string::npos; } - // The breakpoint handler only exits with a explicit 'quit' - return m_active_io_handler != eIOHandlerBreakpoint; + // The breakpoint and watchpoint handler only exits with a explicit 'quit' + return m_active_io_handler != eIOHandlerBreakpoint && + m_active_io_handler != eIOHandlerWatchpoint; } void IOHandlerInputComplete(IOHandler &io_handler, @@ -109,9 +117,13 @@ public: } io_handler.SetIsDone(true); } break; - case eIOHandlerWatchpoint: + case eIOHandlerWatchpoint: { + auto *wp_options = + static_cast(io_handler.GetUserData()); + m_script_interpreter.SetWatchpointCommandCallback(wp_options, + data.c_str()); io_handler.SetIsDone(true); - break; + } break; case eIOHandlerNone: if (IsQuitCommand(data)) { io_handler.SetIsDone(true); @@ -276,6 +288,33 @@ bool ScriptInterpreterLua::BreakpointCallbackFunction( return *BoolOrErr; } +bool ScriptInterpreterLua::WatchpointCallbackFunction( + void *baton, StoppointCallbackContext *context, user_id_t watch_id) { + assert(context); + + ExecutionContext exe_ctx(context->exe_ctx_ref); + Target *target = exe_ctx.GetTargetPtr(); + if (target == nullptr) + return true; + + StackFrameSP stop_frame_sp(exe_ctx.GetFrameSP()); + WatchpointSP wp_sp = target->GetWatchpointList().FindByID(watch_id); + + Debugger &debugger = target->GetDebugger(); + ScriptInterpreterLua *lua_interpreter = static_cast( + debugger.GetScriptInterpreter(true, eScriptLanguageLua)); + Lua &lua = lua_interpreter->GetLua(); + + llvm::Expected BoolOrErr = + lua.CallWatchpointCallback(baton, stop_frame_sp, wp_sp); + if (llvm::Error E = BoolOrErr.takeError()) { + debugger.GetErrorStream() << toString(std::move(E)); + return true; + } + + return *BoolOrErr; +} + void ScriptInterpreterLua::CollectDataForBreakpointCommandCallback( std::vector> &bp_options_vec, CommandReturnObject &result) { @@ -285,6 +324,14 @@ void ScriptInterpreterLua::CollectDataForBreakpointCommandCallback( m_debugger.RunIOHandlerAsync(io_handler_sp); } +void ScriptInterpreterLua::CollectDataForWatchpointCommandCallback( + WatchpointOptions *wp_options, CommandReturnObject &result) { + IOHandlerSP io_handler_sp( + new IOHandlerLuaInterpreter(m_debugger, *this, eIOHandlerWatchpoint)); + io_handler_sp->SetUserData(wp_options); + m_debugger.RunIOHandlerAsync(io_handler_sp); +} + Status ScriptInterpreterLua::SetBreakpointCommandCallbackFunction( BreakpointOptions &bp_options, const char *function_name, StructuredData::ObjectSP extra_args_sp) { @@ -314,6 +361,26 @@ Status ScriptInterpreterLua::RegisterBreakpointCallback( return error; } +void ScriptInterpreterLua::SetWatchpointCommandCallback( + WatchpointOptions *wp_options, const char *command_body_text) { + RegisterWatchpointCallback(wp_options, command_body_text, {}); +} + +Status ScriptInterpreterLua::RegisterWatchpointCallback( + WatchpointOptions *wp_options, const char *command_body_text, + StructuredData::ObjectSP extra_args_sp) { + Status error; + auto data_up = std::make_unique(); + error = m_lua->RegisterWatchpointCallback(data_up.get(), command_body_text); + if (error.Fail()) + return error; + auto baton_sp = + std::make_shared(std::move(data_up)); + wp_options->SetCallback(ScriptInterpreterLua::WatchpointCallbackFunction, + baton_sp); + return error; +} + lldb::ScriptInterpreterSP ScriptInterpreterLua::CreateInstance(Debugger &debugger) { return std::make_shared(debugger); diff --git a/lldb/source/Plugins/ScriptInterpreter/Lua/ScriptInterpreterLua.h b/lldb/source/Plugins/ScriptInterpreter/Lua/ScriptInterpreterLua.h index a6908d2..5eeac56 100644 --- a/lldb/source/Plugins/ScriptInterpreter/Lua/ScriptInterpreterLua.h +++ b/lldb/source/Plugins/ScriptInterpreter/Lua/ScriptInterpreterLua.h @@ -11,6 +11,7 @@ #include +#include "lldb/Breakpoint/WatchpointOptions.h" #include "lldb/Core/StructuredDataImpl.h" #include "lldb/Interpreter/ScriptInterpreter.h" #include "lldb/Utility/Status.h" @@ -63,6 +64,10 @@ public: lldb::user_id_t break_id, lldb::user_id_t break_loc_id); + static bool WatchpointCallbackFunction(void *baton, + StoppointCallbackContext *context, + lldb::user_id_t watch_id); + // PluginInterface protocol lldb_private::ConstString GetPluginName() override; @@ -77,9 +82,16 @@ public: std::vector> &bp_options_vec, CommandReturnObject &result) override; + void + CollectDataForWatchpointCommandCallback(WatchpointOptions *wp_options, + CommandReturnObject &result) override; + Status SetBreakpointCommandCallback(BreakpointOptions &bp_options, const char *command_body_text) override; + void SetWatchpointCommandCallback(WatchpointOptions *wp_options, + const char *command_body_text) override; + Status SetBreakpointCommandCallbackFunction( BreakpointOptions &bp_options, const char *function_name, StructuredData::ObjectSP extra_args_sp) override; @@ -91,6 +103,10 @@ private: Status RegisterBreakpointCallback(BreakpointOptions &bp_options, const char *command_body_text, StructuredData::ObjectSP extra_args_sp); + + Status RegisterWatchpointCallback(WatchpointOptions *wp_options, + const char *command_body_text, + StructuredData::ObjectSP extra_args_sp); }; } // namespace lldb_private diff --git a/lldb/test/Shell/ScriptInterpreter/Lua/watchpoint_callback.test b/lldb/test/Shell/ScriptInterpreter/Lua/watchpoint_callback.test index e5a4329..ddb0df5 100644 --- a/lldb/test/Shell/ScriptInterpreter/Lua/watchpoint_callback.test +++ b/lldb/test/Shell/ScriptInterpreter/Lua/watchpoint_callback.test @@ -1,9 +1,33 @@ # REQUIRES: lua # XFAIL: system-netbsd -# RUN: echo "int main() { return 0; }" | %clang_host -x c - -o %t +# RUN: echo "int main() { int val = 1; val++; return 0; }" | %clang_host -x c - -g -o %t # RUN: %lldb -s %s --script-language lua %t 2>&1 | FileCheck %s b main r -watchpoint set expr 0x0 +watchpoint set variable val watchpoint command add -s lua -# CHECK: error: This script interpreter does not support watchpoint callbacks +print("val=" .. tostring(frame:FindVariable("val"):GetValue())) +quit +c +# CHECK: val=1 +# CHECK: val=2 +# CHECK: Process {{[0-9]+}} exited +r +watchpoint set variable val +watchpoint modify 1 -c "(val == 1)" +watchpoint command add -s lua +print("conditional watchpoint") +wp:SetEnabled(false) +quit +c +# CHECK-COUNT-1: conditional watchpoint +# CHECK-NOT: conditional watchpoint +# CHECK: Process {{[0-9]+}} exited +r +watchpoint set expr 0x00 +watchpoint command add -s lua +print("never triggers") +quit +c +# CHECK-NOT: never triggers +# CHECK: Process {{[0-9]+}} exited diff --git a/lldb/unittests/ScriptInterpreter/Lua/LuaTests.cpp b/lldb/unittests/ScriptInterpreter/Lua/LuaTests.cpp index 76ce3bc..8d849ca 100644 --- a/lldb/unittests/ScriptInterpreter/Lua/LuaTests.cpp +++ b/lldb/unittests/ScriptInterpreter/Lua/LuaTests.cpp @@ -30,6 +30,11 @@ extern "C" llvm::Expected LLDBSwigLuaBreakpointCallbackFunction( return false; } +extern "C" llvm::Expected LLDBSwigLuaWatchpointCallbackFunction( + lua_State *L, lldb::StackFrameSP stop_frame_sp, lldb::WatchpointSP wp_sp) { + return false; +} + #if _MSC_VER #pragma warning (pop) #endif -- 2.7.4