Add functionality to export settings

For the reproducer feature I need to be able to export and import the
current LLDB configuration. To realize this I've extended the existing
functionality to print settings. With the help of a new formatting
option, we can now write the settings and their values to a file
structured as regular commands.

Concretely the functionality works as follows:

  (lldb) settings export -f /path/to/file

This file contains a bunch of settings set commands, followed by the
setting's name and value.

  ...
  settings set use-external-editor false
  settings set use-color true
  settings set auto-one-line-summaries true
  settings set auto-indent true
  ...

You can import the settings again by either sourcing the file or using
the settings read command.

  (lldb) settings read -f /path/to/file

Differential revision: https://reviews.llvm.org/D52651

llvm-svn: 345346

1 files changed, 205 insertions, 0 deletions

diff --git a/lldb/source/Commands/CommandObjectSettings.cpp b/lldb/source/Commands/CommandObjectSettings.cpp
index bde1a80..48ce3753f 100644
--- a/lldb/source/Commands/CommandObjectSettings.cpp
+++ b/lldb/source/Commands/CommandObjectSettings.cpp
@@ -321,6 +321,207 @@ protected:
 };
 
 //-------------------------------------------------------------------------
+// CommandObjectSettingsWrite -- Write settings to file
+//-------------------------------------------------------------------------
+
+static constexpr OptionDefinition g_settings_write_options[] = {
+    // clang-format off
+  { LLDB_OPT_SET_ALL, true,  "file",  'f', OptionParser::eRequiredArgument, nullptr, {}, CommandCompletions::eDiskFileCompletion, eArgTypeFilename,    "The file into which to write the settings." },
+  { LLDB_OPT_SET_ALL, false, "append",'a', OptionParser::eNoArgument,       nullptr, {}, 0,                                       eArgTypeNone,        "Append to saved settings file if it exists."},
+    // clang-format on
+};
+
+class CommandObjectSettingsWrite : public CommandObjectParsed {
+public:
+  CommandObjectSettingsWrite(CommandInterpreter &interpreter)
+      : CommandObjectParsed(
+            interpreter, "settings export",
+            "Write matching debugger settings and their "
+            "current values to a file that can be read in with "
+            "\"settings read\". Defaults to writing all settings.",
+            nullptr),
+        m_options() {
+    CommandArgumentEntry arg1;
+    CommandArgumentData var_name_arg;
+
+    // Define the first (and only) variant of this arg.
+    var_name_arg.arg_type = eArgTypeSettingVariableName;
+    var_name_arg.arg_repetition = eArgRepeatOptional;
+
+    // There is only one variant this argument could be; put it into the
+    // argument entry.
+    arg1.push_back(var_name_arg);
+
+    // Push the data for the first argument into the m_arguments vector.
+    m_arguments.push_back(arg1);
+  }
+
+  ~CommandObjectSettingsWrite() override = default;
+
+  Options *GetOptions() override { return &m_options; }
+
+  class CommandOptions : public Options {
+  public:
+    CommandOptions() : Options() {}
+
+    ~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 'f':
+        m_filename.assign(option_arg);
+        break;
+      case 'a':
+        m_append = true;
+        break;
+      default:
+        error.SetErrorStringWithFormat("unrecognized option '%c'",
+                                       short_option);
+        break;
+      }
+
+      return error;
+    }
+
+    void OptionParsingStarting(ExecutionContext *execution_context) override {
+      m_filename.clear();
+      m_append = false;
+    }
+
+    llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
+      return llvm::makeArrayRef(g_settings_write_options);
+    }
+
+    // Instance variables to hold the values for command options.
+    std::string m_filename;
+    bool m_append = false;
+  };
+
+protected:
+  bool DoExecute(Args &args, CommandReturnObject &result) override {
+    std::string path(FileSpec(m_options.m_filename, true).GetPath());
+    uint32_t options = File::OpenOptions::eOpenOptionWrite |
+                       File::OpenOptions::eOpenOptionCanCreate;
+    if (m_options.m_append)
+      options |= File::OpenOptions::eOpenOptionAppend;
+    else
+      options |= File::OpenOptions::eOpenOptionTruncate;
+
+    StreamFile out_file(path.c_str(), options,
+                        lldb::eFilePermissionsFileDefault);
+
+    if (!out_file.GetFile().IsValid()) {
+      result.AppendErrorWithFormat("%s: unable to write to file", path.c_str());
+      result.SetStatus(eReturnStatusFailed);
+      return false;
+    }
+
+    // Exporting should not be context sensitive.
+    ExecutionContext clean_ctx;
+
+    if (args.empty()) {
+      m_interpreter.GetDebugger().DumpAllPropertyValues(
+          &clean_ctx, out_file, OptionValue::eDumpGroupExport);
+      return result.Succeeded();
+    }
+
+    for (const auto &arg : args) {
+      Status error(m_interpreter.GetDebugger().DumpPropertyValue(
+          &clean_ctx, out_file, arg.ref, OptionValue::eDumpGroupExport));
+      if (!error.Success()) {
+        result.AppendError(error.AsCString());
+        result.SetStatus(eReturnStatusFailed);
+      }
+    }
+
+    return result.Succeeded();
+  }
+
+private:
+  CommandOptions m_options;
+};
+
+//-------------------------------------------------------------------------
+// CommandObjectSettingsRead -- Read settings from file
+//-------------------------------------------------------------------------
+
+static constexpr OptionDefinition g_settings_read_options[] = {
+    // clang-format off
+  {LLDB_OPT_SET_ALL, true, "file",'f', OptionParser::eRequiredArgument, nullptr, {}, CommandCompletions::eDiskFileCompletion, eArgTypeFilename,       "The file from which to read the breakpoints." },
+    // clang-format on
+};
+
+class CommandObjectSettingsRead : public CommandObjectParsed {
+public:
+  CommandObjectSettingsRead(CommandInterpreter &interpreter)
+      : CommandObjectParsed(
+            interpreter, "settings read",
+            "Read settings previously saved to a file with \"settings write\".",
+            nullptr),
+        m_options() {}
+
+  ~CommandObjectSettingsRead() override = default;
+
+  Options *GetOptions() override { return &m_options; }
+
+  class CommandOptions : public Options {
+  public:
+    CommandOptions() : Options() {}
+
+    ~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 'f':
+        m_filename.assign(option_arg);
+        break;
+      default:
+        error.SetErrorStringWithFormat("unrecognized option '%c'",
+                                       short_option);
+        break;
+      }
+
+      return error;
+    }
+
+    void OptionParsingStarting(ExecutionContext *execution_context) override {
+      m_filename.clear();
+    }
+
+    llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
+      return llvm::makeArrayRef(g_settings_read_options);
+    }
+
+    // Instance variables to hold the values for command options.
+    std::string m_filename;
+  };
+
+protected:
+  bool DoExecute(Args &command, CommandReturnObject &result) override {
+    FileSpec file(m_options.m_filename, true);
+    ExecutionContext clean_ctx;
+    CommandInterpreterRunOptions options;
+    options.SetAddToHistory(false);
+    options.SetEchoCommands(false);
+    options.SetPrintResults(true);
+    options.SetStopOnError(false);
+    m_interpreter.HandleCommandsFromFile(file, &clean_ctx, options, result);
+    return result.Succeeded();
+  }
+
+private:
+  CommandOptions m_options;
+};
+
+//-------------------------------------------------------------------------
 // CommandObjectSettingsList -- List settable variables
 //-------------------------------------------------------------------------
 
@@ -1007,6 +1208,10 @@ CommandObjectMultiwordSettings::CommandObjectMultiwordSettings(
                  CommandObjectSP(new CommandObjectSettingsAppend(interpreter)));
   LoadSubCommand("clear",
                  CommandObjectSP(new CommandObjectSettingsClear(interpreter)));
+  LoadSubCommand("write",
+                 CommandObjectSP(new CommandObjectSettingsWrite(interpreter)));
+  LoadSubCommand("read",
+                 CommandObjectSP(new CommandObjectSettingsRead(interpreter)));
 }
 
 CommandObjectMultiwordSettings::~CommandObjectMultiwordSettings() = default;