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)
Differential Revision: https://reviews.llvm.org/D37923
llvm-svn: 315037
diff --git a/lldb/source/API/SBCommandInterpreter.cpp b/lldb/source/API/SBCommandInterpreter.cpp
index aa49539..c9bb8f6 100644
--- a/lldb/source/API/SBCommandInterpreter.cpp
+++ b/lldb/source/API/SBCommandInterpreter.cpp
@@ -161,6 +161,10 @@
return (IsValid() ? m_opaque_ptr->IsActive() : false);
}
+bool SBCommandInterpreter::WasInterrupted() const {
+ return (IsValid() ? m_opaque_ptr->WasInterrupted() : false);
+}
+
const char *SBCommandInterpreter::GetIOHandlerControlSequence(char ch) {
return (IsValid()
? m_opaque_ptr->GetDebugger()
diff --git a/lldb/source/Commands/CommandObjectTarget.cpp b/lldb/source/Commands/CommandObjectTarget.cpp
index bb1b3f8..4eaec5b 100644
--- a/lldb/source/Commands/CommandObjectTarget.cpp
+++ b/lldb/source/Commands/CommandObjectTarget.cpp
@@ -2053,6 +2053,8 @@
result.GetOutputStream().EOL();
result.GetOutputStream().EOL();
}
+ if (m_interpreter.WasInterrupted())
+ break;
num_dumped++;
DumpModuleSymtab(
m_interpreter, result.GetOutputStream(),
@@ -2081,6 +2083,8 @@
result.GetOutputStream().EOL();
result.GetOutputStream().EOL();
}
+ if (m_interpreter.WasInterrupted())
+ break;
num_dumped++;
DumpModuleSymtab(m_interpreter, result.GetOutputStream(),
module, m_options.m_sort_order);
@@ -2146,6 +2150,8 @@
" modules.\n",
(uint64_t)num_modules);
for (size_t image_idx = 0; image_idx < num_modules; ++image_idx) {
+ if (m_interpreter.WasInterrupted())
+ break;
num_dumped++;
DumpModuleSections(
m_interpreter, result.GetOutputStream(),
@@ -2167,6 +2173,8 @@
FindModulesByName(target, arg_cstr, module_list, true);
if (num_matches > 0) {
for (size_t i = 0; i < num_matches; ++i) {
+ if (m_interpreter.WasInterrupted())
+ break;
Module *module = module_list.GetModulePointerAtIndex(i);
if (module) {
num_dumped++;
@@ -2239,6 +2247,8 @@
" modules.\n",
(uint64_t)num_modules);
for (uint32_t image_idx = 0; image_idx < num_modules; ++image_idx) {
+ if (m_interpreter.WasInterrupted())
+ break;
if (DumpModuleSymbolVendor(
result.GetOutputStream(),
target_modules.GetModulePointerAtIndexUnlocked(image_idx)))
@@ -2260,6 +2270,8 @@
FindModulesByName(target, arg_cstr, module_list, true);
if (num_matches > 0) {
for (size_t i = 0; i < num_matches; ++i) {
+ if (m_interpreter.WasInterrupted())
+ break;
Module *module = module_list.GetModulePointerAtIndex(i);
if (module) {
if (DumpModuleSymbolVendor(result.GetOutputStream(), module))
@@ -2327,6 +2339,8 @@
if (num_modules > 0) {
uint32_t num_dumped = 0;
for (uint32_t i = 0; i < num_modules; ++i) {
+ if (m_interpreter.WasInterrupted())
+ break;
if (DumpCompileUnitLineTable(
m_interpreter, result.GetOutputStream(),
target_modules.GetModulePointerAtIndexUnlocked(i),
diff --git a/lldb/source/Core/Debugger.cpp b/lldb/source/Core/Debugger.cpp
index d42e4df..a4d7815 100644
--- a/lldb/source/Core/Debugger.cpp
+++ b/lldb/source/Core/Debugger.cpp
@@ -1170,7 +1170,7 @@
return;
StreamString s;
- const char *prompt_format =
+ const char *prompt_format =
"{addr = '${addr}'\n}"
"{addr-file-or-load = '${addr-file-or-load}'\n}"
"{current-pc-arrow = '${current-pc-arrow}'\n}"
diff --git a/lldb/source/Interpreter/CommandInterpreter.cpp b/lldb/source/Interpreter/CommandInterpreter.cpp
index 5efc6d1..8dc5637 100644
--- a/lldb/source/Interpreter/CommandInterpreter.cpp
+++ b/lldb/source/Interpreter/CommandInterpreter.cpp
@@ -546,7 +546,7 @@
char buffer[1024];
int num_printed =
snprintf(buffer, 1024, "%s %s", break_regexes[i][1], "-o");
- assert(num_printed < 1024);
+ lldbassert(num_printed < 1024);
UNUSED_IF_ASSERT_DISABLED(num_printed);
success =
tbreak_regex_cmd_ap->AddRegexCommand(break_regexes[i][0], buffer);
@@ -891,8 +891,8 @@
const lldb::CommandObjectSP &cmd_sp,
bool can_replace) {
if (cmd_sp.get())
- assert((this == &cmd_sp->GetCommandInterpreter()) &&
- "tried to add a CommandObject from a different interpreter");
+ lldbassert((this == &cmd_sp->GetCommandInterpreter()) &&
+ "tried to add a CommandObject from a different interpreter");
if (name.empty())
return false;
@@ -913,8 +913,8 @@
const lldb::CommandObjectSP &cmd_sp,
bool can_replace) {
if (cmd_sp.get())
- assert((this == &cmd_sp->GetCommandInterpreter()) &&
- "tried to add a CommandObject from a different interpreter");
+ lldbassert((this == &cmd_sp->GetCommandInterpreter()) &&
+ "tried to add a CommandObject from a different interpreter");
if (!name.empty()) {
// do not allow replacement of internal commands
@@ -1062,8 +1062,8 @@
lldb::CommandObjectSP &command_obj_sp,
llvm::StringRef args_string) {
if (command_obj_sp.get())
- assert((this == &command_obj_sp->GetCommandInterpreter()) &&
- "tried to add a CommandObject from a different interpreter");
+ lldbassert((this == &command_obj_sp->GetCommandInterpreter()) &&
+ "tried to add a CommandObject from a different interpreter");
std::unique_ptr<CommandAlias> command_alias_up(
new CommandAlias(*this, command_obj_sp, args_string, alias_name));
@@ -1541,6 +1541,12 @@
if (!no_context_switching)
UpdateExecutionContext(override_context);
+ if (WasInterrupted()) {
+ result.AppendError("interrupted");
+ result.SetStatus(eReturnStatusFailed);
+ return false;
+ }
+
bool add_to_history;
if (lazy_add_to_history == eLazyBoolCalculate)
add_to_history = (m_command_source_depth == 0);
@@ -1839,7 +1845,7 @@
matches.Clear();
// Only max_return_elements == -1 is supported at present:
- assert(max_return_elements == -1);
+ lldbassert(max_return_elements == -1);
bool word_complete;
num_command_matches = HandleCompletionMatches(
parsed_line, cursor_index, cursor_char_position, match_start_point,
@@ -2210,7 +2216,7 @@
m_debugger.SetAsyncExecution(false);
}
- for (size_t idx = 0; idx < num_lines; idx++) {
+ for (size_t idx = 0; idx < num_lines && !WasInterrupted(); idx++) {
const char *cmd = commands.GetStringAtIndex(idx);
if (cmd[0] == '\0')
continue;
@@ -2677,8 +2683,67 @@
return total_bytes;
}
+void CommandInterpreter::StartHandlingCommand() {
+ auto idle_state = CommandHandlingState::eIdle;
+ if (m_command_state.compare_exchange_strong(
+ idle_state, CommandHandlingState::eInProgress))
+ lldbassert(m_iohandler_nesting_level == 0);
+ else
+ lldbassert(m_iohandler_nesting_level > 0);
+ ++m_iohandler_nesting_level;
+}
+
+void CommandInterpreter::FinishHandlingCommand() {
+ lldbassert(m_iohandler_nesting_level > 0);
+ if (--m_iohandler_nesting_level == 0) {
+ auto prev_state = m_command_state.exchange(CommandHandlingState::eIdle);
+ lldbassert(prev_state != CommandHandlingState::eIdle);
+ }
+}
+
+bool CommandInterpreter::InterruptCommand() {
+ auto in_progress = CommandHandlingState::eInProgress;
+ return m_command_state.compare_exchange_strong(
+ in_progress, CommandHandlingState::eInterrupted);
+}
+
+bool CommandInterpreter::WasInterrupted() const {
+ bool was_interrupted =
+ (m_command_state == CommandHandlingState::eInterrupted);
+ lldbassert(!was_interrupted || m_iohandler_nesting_level > 0);
+ return was_interrupted;
+}
+
+void CommandInterpreter::PrintCommandOutput(Stream &stream,
+ llvm::StringRef str) {
+ // Split the output into lines and poll for interrupt requests
+ const char *data = str.data();
+ size_t size = str.size();
+ while (size > 0 && !WasInterrupted()) {
+ size_t chunk_size = 0;
+ for (; chunk_size < size; ++chunk_size) {
+ lldbassert(data[chunk_size] != '\0');
+ if (data[chunk_size] == '\n') {
+ ++chunk_size;
+ break;
+ }
+ }
+ chunk_size = stream.Write(data, chunk_size);
+ lldbassert(size >= chunk_size);
+ data += chunk_size;
+ size -= chunk_size;
+ }
+ if (size > 0) {
+ stream.Printf("\n... Interrupted.\n");
+ }
+}
+
void CommandInterpreter::IOHandlerInputComplete(IOHandler &io_handler,
std::string &line) {
+ // If we were interrupted, bail out...
+ if (WasInterrupted())
+ return;
+
const bool is_interactive = io_handler.GetIsInteractive();
if (is_interactive == false) {
// When we are not interactive, don't execute blank lines. This will happen
@@ -2700,6 +2765,8 @@
line.c_str());
}
+ StartHandlingCommand();
+
lldb_private::CommandReturnObject result;
HandleCommand(line.c_str(), eLazyBoolCalculate, result);
@@ -2710,18 +2777,18 @@
if (!result.GetImmediateOutputStream()) {
llvm::StringRef output = result.GetOutputData();
- if (!output.empty())
- io_handler.GetOutputStreamFile()->PutCString(output);
+ PrintCommandOutput(*io_handler.GetOutputStreamFile(), output);
}
// Now emit the command error text from the command we just executed
if (!result.GetImmediateErrorStream()) {
llvm::StringRef error = result.GetErrorData();
- if (!error.empty())
- io_handler.GetErrorStreamFile()->PutCString(error);
+ PrintCommandOutput(*io_handler.GetErrorStreamFile(), error);
}
}
+ FinishHandlingCommand();
+
switch (result.GetStatus()) {
case eReturnStatusInvalid:
case eReturnStatusSuccessFinishNoResult:
@@ -2777,6 +2844,9 @@
ExecutionContext exe_ctx(GetExecutionContext());
Process *process = exe_ctx.GetProcessPtr();
+ if (InterruptCommand())
+ return true;
+
if (process) {
StateType state = process->GetState();
if (StateIsRunningState(state)) {
@@ -2998,7 +3068,7 @@
result.AppendRawError(error_msg.GetString());
} else {
// We didn't have only one match, otherwise we wouldn't get here.
- assert(num_matches == 0);
+ lldbassert(num_matches == 0);
result.AppendErrorWithFormat("'%s' is not a valid command.\n",
next_word.c_str());
}