Cherrypick LLDB statusline

lldb/docs/use/formatting.rst

@@ -113,11 +113,11 @@ A complete list of currently supported format string variables is listed below:
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
 | ``module.file.basename``                          | The basename of the current module (shared library or executable)                                                                                                                                                                                                                           |
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
-| ``module.file.fullpath``                          | The basename of the current module (shared library or executable)                                                                                                                                                                                                                           |
+| ``module.file.fullpath``                          | The path of the current module (shared library or executable)                                                                                                                                                                                                                               |
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
 | ``process.file.basename``                         | The basename of the file for the process                                                                                                                                                                                                                                                    |
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
-| ``process.file.fullpath``                         | The fullname of the file for the process                                                                                                                                                                                                                                                    |
+| ``process.file.fullpath``                         | The path of the file for the process                                                                                                                                                                                                                                                        |
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
 | ``process.id``                                    | The process ID native to the system on which the inferior runs.                                                                                                                                                                                                                             |
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
@@ -141,6 +141,10 @@ A complete list of currently supported format string variables is listed below:
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
 | ``target.arch``                                   | The architecture of the current target                                                                                                                                                                                                                                                      |
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+| ``target.file.basename``                          | The basename of the current target                                                                                                                                                                                                                                                          |
++---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+| ``target.file.fullpath``                          | The path of the current target                                                                                                                                                                                                                                                              |
++---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
 | ``script.target:python_func``                     | Use a Python function to generate a piece of textual output                                                                                                                                                                                                                                 |
 +---------------------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
 | ``script.process:python_func``                    | Use a Python function to generate a piece of textual output                                                                                                                                                                                                                                 |

lldb/include/lldb/Core/Debugger.h

@@ -19,6 +19,7 @@
 #include "lldb/Core/FormatEntity.h"
 #include "lldb/Core/IOHandler.h"
 #include "lldb/Core/SourceManager.h"
+#include "lldb/Core/Statusline.h"
 #include "lldb/Core/UserSettingsController.h"
 #include "lldb/Host/HostThread.h"
 #include "lldb/Host/StreamFile.h"
@@ -307,6 +308,10 @@ class Debugger : public std::enable_shared_from_this<Debugger>,
 
   bool SetShowProgress(bool show_progress);
 
+  bool GetShowStatusline() const;
+
+  const FormatEntity::Entry *GetStatuslineFormat() const;
+
   llvm::StringRef GetShowProgressAnsiPrefix() const;
 
   llvm::StringRef GetShowProgressAnsiSuffix() const;
@@ -420,6 +425,9 @@ class Debugger : public std::enable_shared_from_this<Debugger>,
   /// Decrement the "interrupt requested" counter.
   void CancelInterruptRequest();
 
+  /// Redraw the statusline if enabled.
+  void RedrawStatusline(bool update = true);
+
   /// This is the correct way to query the state of Interruption.
   /// If you are on the RunCommandInterpreter thread, it will check the
   /// command interpreter state, and if it is on another thread it will
@@ -607,12 +615,21 @@ class Debugger : public std::enable_shared_from_this<Debugger>,
     return m_source_file_cache;
   }
 
+  struct ProgressReport {
+    uint64_t id;
+    uint64_t completed;
+    uint64_t total;
+    std::string message;
+  };
+  std::optional<ProgressReport> GetCurrentProgressReport() const;
+
 protected:
   friend class CommandInterpreter;
   friend class SwiftREPL;
   friend class REPL;
   friend class Progress;
   friend class ProgressManager;
+  friend class Statusline;
 
   /// Report progress events.
   ///
@@ -665,6 +682,8 @@ class Debugger : public std::enable_shared_from_this<Debugger>,
   lldb::LockableStreamFileSP GetErrorStreamSP() { return m_error_stream_sp; }
   /// @}
 
+  bool StatuslineSupported();
+
   void PushIOHandler(const lldb::IOHandlerSP &reader_sp,
                      bool cancel_top_handler = true);
 
@@ -741,7 +760,7 @@ class Debugger : public std::enable_shared_from_this<Debugger>,
   IOHandlerStack m_io_handler_stack;
   std::recursive_mutex m_io_handler_synchronous_mutex;
 
-  std::optional<uint64_t> m_current_event_id;
+  std::optional<Statusline> m_statusline;
 
   llvm::StringMap<std::weak_ptr<LogHandler>> m_stream_handlers;
   std::shared_ptr<CallbackLogHandler> m_callback_handler_sp;
@@ -758,6 +777,12 @@ class Debugger : public std::enable_shared_from_this<Debugger>,
   lldb::TargetSP m_dummy_target_sp;
   Diagnostics::CallbackID m_diagnostics_callback_id;
 
+  /// Bookkeeping for command line progress events.
+  /// @{
+  llvm::SmallVector<ProgressReport, 4> m_progress_reports;
+  mutable std::mutex m_progress_reports_mutex;
+  /// @}
+
   std::mutex m_destroy_callback_mutex;
   lldb::callback_token_t m_destroy_callback_next_token = 0;
   struct DestroyCallbackInfo {

lldb/include/lldb/Core/FormatEntity.h

@@ -67,6 +67,7 @@ struct Entry {
     ScriptThread,
     ThreadInfo,
     TargetArch,
+    TargetFile,
     ScriptTarget,
     ModuleFile,
     File,
@@ -99,7 +100,9 @@ struct Entry {
     LineEntryColumn,
     LineEntryStartAddress,
     LineEntryEndAddress,
-    CurrentPCArrow
+    CurrentPCArrow,
+    ProgressCount,
+    ProgressMessage,
   };
 
   struct Definition {

lldb/include/lldb/Core/IOHandler.h

@@ -406,6 +406,8 @@ class IOHandlerEditline : public IOHandler {
   std::optional<std::string> SuggestionCallback(llvm::StringRef line);
 
   void AutoCompleteCallback(CompletionRequest &request);
+
+  void RedrawCallback();
 #endif
 
 protected:

lldb/include/lldb/Core/Statusline.h

@@ -0,0 +1,67 @@
+//===-- Statusline.h -----------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_CORE_STATUSLINE_H
+#define LLDB_CORE_STATUSLINE_H
+
+#include "lldb/lldb-forward.h"
+#include "llvm/ADT/StringRef.h"
+#include <csignal>
+#include <cstdint>
+#include <string>
+
+namespace lldb_private {
+class Statusline {
+public:
+  Statusline(Debugger &debugger);
+  ~Statusline();
+
+  /// Reduce the scroll window and draw the statusline.
+  void Enable();
+
+  /// Hide the statusline and extend the scroll window.
+  void Disable();
+
+  /// Redraw the statusline. If update is false, this will redraw the last
+  /// string.
+  void Redraw(bool update = true);
+
+  /// Inform the statusline that the terminal dimensions have changed.
+  void TerminalSizeChanged();
+
+protected:
+  /// Pad and trim the given string to fit to the given width.
+  static std::string TrimAndPad(std::string str, size_t width);
+
+private:
+  /// Draw the statusline with the given text.
+  void Draw(std::string msg);
+
+  /// Update terminal dimensions.
+  void UpdateTerminalProperties();
+
+  enum ScrollWindowMode {
+    ScrollWindowExtend,
+    ScrollWindowShrink,
+  };
+
+  /// Set the scroll window for the given mode.
+  void UpdateScrollWindow(ScrollWindowMode mode);
+
+  /// Clear the statusline (without redrawing the background).
+  void Reset();
+
+  Debugger &m_debugger;
+  std::string m_last_str;
+
+  volatile std::sig_atomic_t m_terminal_size_has_changed = 1;
+  uint64_t m_terminal_width = 0;
+  uint64_t m_terminal_height = 0;
+};
+} // namespace lldb_private
+#endif // LLDB_CORE_STATUSLINE_H

lldb/include/lldb/Host/Editline.h

@@ -102,6 +102,8 @@ using SuggestionCallbackType =
 
 using CompleteCallbackType = llvm::unique_function<void(CompletionRequest &)>;
 
+using RedrawCallbackType = llvm::unique_function<void()>;
+
 /// Status used to decide when and how to start editing another line in
 /// multi-line sessions.
 enum class EditorStatus {
@@ -194,6 +196,11 @@ class Editline {
     m_suggestion_callback = std::move(callback);
   }
 
+  /// Register a callback for redrawing the statusline.
+  void SetRedrawCallback(RedrawCallbackType callback) {
+    m_redraw_callback = std::move(callback);
+  }
+
   /// Register a callback for the tab key
   void SetAutoCompleteCallback(CompleteCallbackType callback) {
     m_completion_callback = std::move(callback);
@@ -409,6 +416,7 @@ class Editline {
 
   CompleteCallbackType m_completion_callback;
   SuggestionCallbackType m_suggestion_callback;
+  RedrawCallbackType m_redraw_callback;
 
   bool m_color;
   std::string m_prompt_ansi_prefix;

lldb/include/lldb/Utility/AnsiTerminal.h

@@ -70,9 +70,12 @@
 #define ANSI_1_CTRL(ctrl1) "\033["##ctrl1 ANSI_ESC_END
 #define ANSI_2_CTRL(ctrl1, ctrl2) "\033["##ctrl1 ";"##ctrl2 ANSI_ESC_END
 
+#define ANSI_ESC_START_LEN 2
+
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Locale.h"
 
 #include <string>
 
@@ -172,28 +175,89 @@ inline std::string FormatAnsiTerminalCodes(llvm::StringRef format,
   return fmt;
 }
 
+inline std::tuple<llvm::StringRef, llvm::StringRef, llvm::StringRef>
+FindNextAnsiSequence(llvm::StringRef str) {
+  llvm::StringRef left;
+  llvm::StringRef right = str;
+
+  while (!right.empty()) {
+    const size_t start = right.find(ANSI_ESC_START);
+
+    // ANSI_ESC_START not found.
+    if (start == llvm::StringRef::npos)
+      return {str, {}, {}};
+
+    // Split the string around the current ANSI_ESC_START.
+    left = str.take_front(left.size() + start);
+    llvm::StringRef escape = right.substr(start);
+    right = right.substr(start + ANSI_ESC_START_LEN + 1);
+
+    const size_t end = right.find_first_not_of("0123456789;");
+
+    // ANSI_ESC_END found.
+    if (end < right.size() && (right[end] == 'm' || right[end] == 'G'))
+      return {left, escape.take_front(ANSI_ESC_START_LEN + 1 + end + 1),
+              right.substr(end + 1)};
+
+    // Maintain the invariant that str == left + right at the start of the loop.
+    left = str.take_front(left.size() + ANSI_ESC_START_LEN + 1);
+  }
+
+  return {str, {}, {}};
+}
+
 inline std::string StripAnsiTerminalCodes(llvm::StringRef str) {
   std::string stripped;
   while (!str.empty()) {
-    llvm::StringRef left, right;
-
-    std::tie(left, right) = str.split(ANSI_ESC_START);
+    auto [left, escape, right] = FindNextAnsiSequence(str);
     stripped += left;
+    str = right;
+  }
+  return stripped;
+}
 
-    // ANSI_ESC_START not found.
-    if (left == str && right.empty())
-      break;
+inline std::string TrimAndPad(llvm::StringRef str, size_t visible_length,
+                              char padding = ' ') {
+  std::string result;
+  result.reserve(visible_length);
+  size_t result_visibile_length = 0;
 
-    size_t end = right.find_first_not_of("0123456789;");
-    if (end < right.size() && (right[end] == 'm' || right[end] == 'G')) {
-      str = right.substr(end + 1);
-    } else {
-      // ANSI_ESC_END not found.
-      stripped += ANSI_ESC_START;
-      str = right;
+  // Trim the string to the given visible length.
+  while (!str.empty()) {
+    auto [left, escape, right] = FindNextAnsiSequence(str);
+    str = right;
+
+    // Compute the length of the string without escape codes. If it fits, append
+    // it together with the invisible escape code.
+    size_t column_width = llvm::sys::locale::columnWidth(left);
+    if (result_visibile_length + column_width <= visible_length) {
+      result.append(left).append(escape);
+      result_visibile_length += column_width;
+      continue;
+    }
+
+    // The string might contain unicode which means it's not safe to truncate.
+    // Repeatedly trim the string until it its valid unicode and fits.
+    llvm::StringRef trimmed = left;
+    while (!trimmed.empty()) {
+      // This relies on columnWidth returning -2 for invalid/partial unicode
+      // characters, which after conversion to size_t will be larger than the
+      // visible width.
+      column_width = llvm::sys::locale::columnWidth(trimmed);
+      if (result_visibile_length + column_width <= visible_length) {
+        result.append(trimmed);
+        result_visibile_length += column_width;
+        break;
+      }
+      trimmed = trimmed.drop_back();
     }
   }
-  return stripped;
+
+  // Pad the string.
+  if (result_visibile_length < visible_length)
+    result.append(visible_length - result_visibile_length, padding);
+
+  return result;
 }
 
 } // namespace ansi

lldb/packages/Python/lldbsuite/test/lldbtest.py

@@ -771,6 +771,10 @@ def setUpCommands(cls):
             'settings set symbols.clang-modules-cache-path "{}"'.format(
                 configuration.lldb_module_cache_dir
             ),
+            # Disable colors by default.
+            "settings set use-color false",
+            # Disable the statusline by default.
+            "settings set show-statusline false",
             # Enable the swift metadata cache in order to speed up tests.
             "settings set symbols.enable-swift-metadata-cache true",
             'settings set symbols.swift-metadata-cache-path "{}"'.format(
@@ -779,7 +783,6 @@ def setUpCommands(cls):
             # Enable expensive validations in TypeSystemSwiftTypeRef.
             "settings set symbols.swift-validate-typesystem true",
             "settings set symbols.swift-typesystem-compiler-fallback true",
-            "settings set use-color false",
         ]
 
         # Set any user-overridden settings.

lldb/source/Core/CMakeLists.txt

@@ -47,6 +47,7 @@ add_lldb_library(lldbCore
   Opcode.cpp
   PluginManager.cpp
   Progress.cpp
+  Statusline.cpp
   RichManglingContext.cpp
   SearchFilter.cpp
   Section.cpp

lldb/source/Core/CoreProperties.td

@@ -225,6 +225,14 @@ let Definition = "debugger" in {
     Global,
     DefaultStringValue<"${ansi.normal}">,
     Desc<"When displaying progress in a color-enabled terminal, use the ANSI terminal code specified in this format immediately after the progress message.">;
+  def ShowStatusline: Property<"show-statusline", "Boolean">,
+    Global,
+    DefaultTrue,
+    Desc<"Whether to show a statusline at the bottom of the terminal.">;
+  def StatuslineFormat: Property<"statusline-format", "FormatEntity">,
+    Global,
+    DefaultStringValue<"${ansi.negative}{${target.file.basename}}{ | ${line.file.basename}:${line.number}:${line.column}}{ | ${thread.stop-reason}}{ | {${progress.count} }${progress.message}}">,
+    Desc<"The default statusline format string.">;
   def UseSourceCache: Property<"use-source-cache", "Boolean">,
     Global,
     DefaultTrue,