[lldb/Commands] Add scripting template list command with auto discovery

This patch introduces a new `template` multiword sub-command to the
`scripting` top-level command. As the name suggests, this sub-command
operates on scripting templates, and currently has the ability to
automatically discover the various scripting extensions that lldb
supports.

Signed-off-by: Med Ismail Bennani <[email protected]>

Author: medismailben

lldb/include/lldb/Core/PluginManager.h

@@ -487,6 +487,33 @@ class PluginManager {
 
   static LanguageSet GetAllTypeSystemSupportedLanguagesForExpressions();
 
+  // Scripted Interface
+  static bool
+  RegisterPlugin(llvm::StringRef name, llvm::StringRef description,
+                 ScriptedInterfaceCreateInstance create_callback,
+                 lldb::ScriptLanguage language,
+                 std::vector<llvm::StringRef> command_interpreter_usages,
+                 std::vector<llvm::StringRef> api_usages);
+
+  static bool UnregisterPlugin(ScriptedInterfaceCreateInstance create_callback);
+
+  static ScriptedInterfaceCreateInstance
+  GetScriptedInterfaceCreateCallbackAtIndex(uint32_t idx);
+
+  static uint32_t GetNumScriptedInterfaces();
+
+  static llvm::StringRef GetScriptedInterfaceNameAtIndex(uint32_t idx);
+
+  static llvm::StringRef GetScriptedInterfaceDescriptionAtIndex(uint32_t idx);
+
+  static lldb::ScriptLanguage GetScriptedInterfaceLanguageAtIndex(uint32_t idx);
+
+  static std::vector<llvm::StringRef>
+  GetScriptedInterfaceCommandInterpreterUsagesAtIndex(uint32_t idx);
+
+  static std::vector<llvm::StringRef>
+  GetScriptedInterfaceAPIUsagesAtIndex(uint32_t idx);
+
   // REPL
   static bool RegisterPlugin(llvm::StringRef name, llvm::StringRef description,
                              REPLCreateInstance create_callback,

lldb/include/lldb/Interpreter/Interfaces/ScriptedInterface.h

@@ -68,6 +68,13 @@ class ScriptedInterface {
     return true;
   }
 
+  static bool
+  CreateInstance(lldb::ScriptLanguage language,
+                 std::vector<llvm::StringRef> command_interpreter_usages,
+                 std::vector<llvm::StringRef> api_usages) {
+    return false;
+  }
+
 protected:
   StructuredData::GenericSP m_object_instance_sp;
 };

lldb/include/lldb/lldb-private-interfaces.h

@@ -124,6 +124,10 @@ typedef lldb::REPLSP (*REPLCreateInstance)(Status &error,
                                            lldb::LanguageType language,
                                            Debugger *debugger, Target *target,
                                            const char *repl_options);
+typedef bool (*ScriptedInterfaceCreateInstance)(
+    lldb::ScriptLanguage language,
+    std::vector<llvm::StringRef> command_interpreter_usages,
+    std::vector<llvm::StringRef> api_usages);
 typedef int (*ComparisonFunction)(const void *, const void *);
 typedef void (*DebuggerInitializeCallback)(Debugger &debugger);
 /// Trace

lldb/source/Commands/CommandObjectScripting.cpp

@@ -8,6 +8,7 @@
 
 #include "CommandObjectScripting.h"
 #include "lldb/Core/Debugger.h"
+#include "lldb/Core/PluginManager.h"
 #include "lldb/DataFormatters/DataVisualization.h"
 #include "lldb/Host/Config.h"
 #include "lldb/Host/OptionParser.h"
@@ -21,6 +22,8 @@
 using namespace lldb;
 using namespace lldb_private;
 
+#pragma mark CommandObjectScriptingRun
+
 #define LLDB_OPTIONS_scripting_run
 #include "CommandOptions.inc"
 
@@ -127,6 +130,157 @@ class CommandObjectScriptingRun : public CommandObjectRaw {
   CommandOptions m_options;
 };
 
+#pragma mark CommandObjectScriptingTemplateList
+
+#define LLDB_OPTIONS_scripting_template_list
+#include "CommandOptions.inc"
+
+class CommandObjectScriptingTemplateList : public CommandObjectParsed {
+public:
+  CommandObjectScriptingTemplateList(CommandInterpreter &interpreter)
+      : CommandObjectParsed(
+            interpreter, "scripting template list",
+            "List all the available scripting affordances templates. ",
+            "scripting template list [--language <scripting-language> --]") {}
+
+  ~CommandObjectScriptingTemplateList() override = default;
+
+  Options *GetOptions() override { return &m_options; }
+
+  class CommandOptions : public Options {
+  public:
+    CommandOptions() = default;
+    ~CommandOptions() override = default;
+    Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
+                          ExecutionContext *execution_context) override {
+      Status error;
+      const int short_option = m_getopt_table[option_idx].val;
+
+      switch (short_option) {
+      case 'l':
+        m_language = (lldb::ScriptLanguage)OptionArgParser::ToOptionEnum(
+            option_arg, GetDefinitions()[option_idx].enum_values,
+            eScriptLanguageNone, error);
+        if (!error.Success())
+          error.SetErrorStringWithFormat("unrecognized value for language '%s'",
+                                         option_arg.str().c_str());
+        break;
+      default:
+        llvm_unreachable("Unimplemented option");
+      }
+
+      return error;
+    }
+
+    void OptionParsingStarting(ExecutionContext *execution_context) override {
+      m_language = lldb::eScriptLanguageDefault;
+    }
+
+    llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
+      return llvm::ArrayRef(g_scripting_template_list_options);
+    }
+
+    lldb::ScriptLanguage m_language = lldb::eScriptLanguageDefault;
+  };
+
+protected:
+  void DoExecute(Args &command, CommandReturnObject &result) override {
+    Stream &s = result.GetOutputStream();
+    s.Printf("Available scripted extension templates:");
+
+    auto print_field = [&s](llvm::StringRef key, llvm::StringRef value,
+                            bool check_validity = false) {
+      if (!check_validity || !value.empty()) {
+        s.IndentMore();
+        s.Indent();
+        s << key << ": " << value << '\n';
+        s.IndentLess();
+      }
+    };
+
+    auto print_usages = [&s](llvm::StringRef usage_kind,
+                             std::vector<llvm::StringRef> &usages) {
+      s.IndentMore();
+      s.Indent();
+      s << usage_kind << " Usages:";
+      if (usages.empty())
+        s << " None\n";
+      else if (usages.size() == 1)
+        s << " " << usages.front() << '\n';
+      else {
+        s << '\n';
+        for (llvm::StringRef usage : usages) {
+          s.IndentMore();
+          s.Indent();
+          s << usage << '\n';
+          s.IndentLess();
+        }
+      }
+      s.IndentLess();
+    };
+
+    size_t num_listed_interface = 0;
+    size_t num_templates = PluginManager::GetNumScriptedInterfaces();
+    for (size_t i = 0; i < num_templates; i++) {
+      llvm::StringRef plugin_name =
+          PluginManager::GetScriptedInterfaceNameAtIndex(i);
+      if (plugin_name.empty())
+        break;
+
+      lldb::ScriptLanguage lang =
+          PluginManager::GetScriptedInterfaceLanguageAtIndex(i);
+      if (lang != m_options.m_language)
+        continue;
+
+      if (!num_listed_interface)
+        s.EOL();
+
+      num_listed_interface++;
+
+      llvm::StringRef desc =
+          PluginManager::GetScriptedInterfaceDescriptionAtIndex(i);
+      std::vector<llvm::StringRef> ci_usages =
+          PluginManager::GetScriptedInterfaceCommandInterpreterUsagesAtIndex(i);
+      std::vector<llvm::StringRef> api_usages =
+          PluginManager::GetScriptedInterfaceAPIUsagesAtIndex(i);
+
+      print_field("Name", plugin_name);
+      print_field("Language", ScriptInterpreter::LanguageToString(lang));
+      print_field("Description", desc);
+      print_usages("Command Interpreter", ci_usages);
+      print_usages("API", api_usages);
+
+      if (i != num_templates - 1)
+        s.EOL();
+    }
+
+    if (!num_listed_interface)
+      s << " None\n";
+  }
+
+private:
+  CommandOptions m_options;
+};
+
+#pragma mark CommandObjectMultiwordScriptingTemplate
+
+// CommandObjectMultiwordScriptingTemplate
+
+class CommandObjectMultiwordScriptingTemplate : public CommandObjectMultiword {
+public:
+  CommandObjectMultiwordScriptingTemplate(CommandInterpreter &interpreter)
+      : CommandObjectMultiword(
+            interpreter, "scripting template",
+            "Commands for operating on the scripting templates.",
+            "scripting template [<subcommand-options>]") {
+    LoadSubCommand(
+        "list",
+        CommandObjectSP(new CommandObjectScriptingTemplateList(interpreter)));
+  }
+
+  ~CommandObjectMultiwordScriptingTemplate() override = default;
+};
+
 #pragma mark CommandObjectMultiwordScripting
 
 // CommandObjectMultiwordScripting
@@ -139,6 +293,9 @@ CommandObjectMultiwordScripting::CommandObjectMultiwordScripting(
           "scripting <subcommand> [<subcommand-options>]") {
   LoadSubCommand("run",
                  CommandObjectSP(new CommandObjectScriptingRun(interpreter)));
+  LoadSubCommand("template",
+                 CommandObjectSP(
+                     new CommandObjectMultiwordScriptingTemplate(interpreter)));
 }
 
 CommandObjectMultiwordScripting::~CommandObjectMultiwordScripting() = default;

lldb/source/Commands/Options.td

@@ -841,6 +841,12 @@ let Command = "scripting run" in {
     " language. If none is specific the default scripting language is used.">;
 }
 
+let Command = "scripting template list" in {
+  def scripting_template_list_language : Option<"language", "l">,
+    EnumArg<"ScriptLang">, Desc<"Specify the scripting "
+    " language. If none is specified the default scripting language is used.">;
+}
+
 let Command = "source info" in {
   def source_info_count : Option<"count", "c">, Arg<"Count">,
     Desc<"The number of line entries to display.">;

lldb/source/Core/PluginManager.cpp

@@ -1479,6 +1479,92 @@ LanguageSet PluginManager::GetAllTypeSystemSupportedLanguagesForExpressions() {
   return all;
 }
 
+#pragma mark ScriptedInterfaces
+
+struct ScriptedInterfaceInstance
+    : public PluginInstance<ScriptedInterfaceCreateInstance> {
+  ScriptedInterfaceInstance(
+      llvm::StringRef name, llvm::StringRef description,
+      ScriptedInterfaceCreateInstance create_callback,
+      lldb::ScriptLanguage language,
+      std::vector<llvm::StringRef> command_interpreter_usages,
+      std::vector<llvm::StringRef> api_usages)
+      : PluginInstance<ScriptedInterfaceCreateInstance>(name, description,
+                                                        create_callback),
+        language(language),
+        command_interpreter_usages(command_interpreter_usages),
+        api_usages(api_usages) {}
+
+  lldb::ScriptLanguage language;
+  std::vector<llvm::StringRef> command_interpreter_usages;
+  std::vector<llvm::StringRef> api_usages;
+};
+
+typedef PluginInstances<ScriptedInterfaceInstance> ScriptedInterfaceInstances;
+
+static ScriptedInterfaceInstances &GetScriptedInterfaceInstances() {
+  static ScriptedInterfaceInstances g_instances;
+  return g_instances;
+}
+
+bool PluginManager::RegisterPlugin(
+    llvm::StringRef name, llvm::StringRef description,
+    ScriptedInterfaceCreateInstance create_callback,
+    lldb::ScriptLanguage language,
+    std::vector<llvm::StringRef> command_interpreter_usages,
+    std::vector<llvm::StringRef> api_usages) {
+  return GetScriptedInterfaceInstances().RegisterPlugin(
+      name, description, create_callback, language, command_interpreter_usages,
+      api_usages);
+}
+
+bool PluginManager::UnregisterPlugin(
+    ScriptedInterfaceCreateInstance create_callback) {
+  return GetScriptedInterfaceInstances().UnregisterPlugin(create_callback);
+}
+
+ScriptedInterfaceCreateInstance
+PluginManager::GetScriptedInterfaceCreateCallbackAtIndex(uint32_t idx) {
+  return GetScriptedInterfaceInstances().GetCallbackAtIndex(idx);
+}
+
+uint32_t PluginManager::GetNumScriptedInterfaces() {
+  return GetScriptedInterfaceInstances().GetInstances().size();
+}
+
+llvm::StringRef PluginManager::GetScriptedInterfaceNameAtIndex(uint32_t index) {
+  return GetScriptedInterfaceInstances().GetNameAtIndex(index);
+}
+
+llvm::StringRef
+PluginManager::GetScriptedInterfaceDescriptionAtIndex(uint32_t index) {
+  return GetScriptedInterfaceInstances().GetDescriptionAtIndex(index);
+}
+
+lldb::ScriptLanguage
+PluginManager::GetScriptedInterfaceLanguageAtIndex(uint32_t idx) {
+  const auto &instances = GetScriptedInterfaceInstances().GetInstances();
+  return idx < instances.size() ? instances[idx].language
+                                : ScriptLanguage::eScriptLanguageNone;
+}
+
+std::vector<llvm::StringRef>
+PluginManager::GetScriptedInterfaceCommandInterpreterUsagesAtIndex(
+    uint32_t idx) {
+  const auto &instances = GetScriptedInterfaceInstances().GetInstances();
+  if (idx >= instances.size())
+    return {};
+  return instances[idx].command_interpreter_usages;
+}
+
+std::vector<llvm::StringRef>
+PluginManager::GetScriptedInterfaceAPIUsagesAtIndex(uint32_t idx) {
+  const auto &instances = GetScriptedInterfaceInstances().GetInstances();
+  if (idx >= instances.size())
+    return {};
+  return instances[idx].api_usages;
+}
+
 #pragma mark REPL
 
 struct REPLInstance : public PluginInstance<REPLCreateInstance> {
@@ -1539,6 +1625,7 @@ void PluginManager::DebuggerInitialize(Debugger &debugger) {
   GetOperatingSystemInstances().PerformDebuggerCallback(debugger);
   GetStructuredDataPluginInstances().PerformDebuggerCallback(debugger);
   GetTracePluginInstances().PerformDebuggerCallback(debugger);
+  GetScriptedInterfaceInstances().PerformDebuggerCallback(debugger);
 }
 
 // This is the preferred new way to register plugin specific settings.  e.g.

lldb/source/Plugins/CMakeLists.txt

@@ -29,6 +29,9 @@ add_subdirectory(UnwindAssembly)
 
 set(LLDB_STRIPPED_PLUGINS)
 get_property(LLDB_ALL_PLUGINS GLOBAL PROPERTY LLDB_PLUGINS)
+get_property(LLDB_EXTRA_PLUGINS GLOBAL PROPERTY LLDB_EXTRA_SCRIPT_PLUGINS)
+list(APPEND LLDB_ALL_PLUGINS ${LLDB_EXTRA_PLUGINS})
+
 
 set(LLDB_ENUM_PLUGINS "")
 

lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/CMakeLists.txt

@@ -19,6 +19,12 @@ if (LLDB_ENABLE_LIBEDIT)
   list(APPEND LLDB_LIBEDIT_LIBS LibEdit::LibEdit)
 endif()
 
+set_property(GLOBAL PROPERTY LLDB_EXTRA_SCRIPT_PLUGINS
+  lldbPluginOperatingSystemPythonInterface
+  lldbPluginScriptedProcessPythonInterface
+  lldbPluginScriptedThreadPlanPythonInterface
+)
+
 add_lldb_library(lldbPluginScriptInterpreterPythonInterfaces
   OperatingSystemPythonInterface.cpp
   ScriptedPythonInterface.cpp