Separating the 'task shell' command in a separate executable 'tasksh' and enabling command history traversal using GNU Readline

src/commands/CmdShell.cpp

@@ -1,132 +0,0 @@
-////////////////////////////////////////////////////////////////////////////////
-// taskwarrior - a command line task list manager.
-//
-// Copyright 2006-2012, Paul Beckingham, Federico Hernandez.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included
-// in all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
-// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
-// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-// SOFTWARE.
-//
-// http://www.opensource.org/licenses/mit-license.php
-//
-////////////////////////////////////////////////////////////////////////////////
-
-#define L10N                                           // Localization complete.
-
-#include <iostream>
-#include <algorithm>
-#include <Color.h>
-#include <Context.h>
-#include <text.h>
-#include <i18n.h>
-#include <CmdShell.h>
-
-extern Context context;
-
-////////////////////////////////////////////////////////////////////////////////
-CmdShell::CmdShell ()
-{
-  _keyword     = "shell";
-  _usage       = "task          shell";
-  _description = STRING_CMD_SHELL_USAGE;
-  _read_only   = false;
-  _displays_id = true;
-}
-
-////////////////////////////////////////////////////////////////////////////////
-int CmdShell::execute (std::string&)
-{
-  // Display some kind of welcome message.
-  Color bold (Color::nocolor, Color::nocolor, false, true, false);
-  std::cout << (context.color () ? bold.colorize (PACKAGE_STRING) : PACKAGE_STRING)
-            << " shell\n\n"
-            << STRING_CMD_SHELL_HELP1 << "\n"
-            << STRING_CMD_SHELL_HELP2 << "\n"
-            << STRING_CMD_SHELL_HELP3 << "\n\n";
-
-  // Make a copy because context.clear will delete them.
-  std::string permanent_overrides;
-  std::vector <Arg>::iterator i;
-  for (i = context.a3.begin (); i != context.a3.end (); ++i)
-  {
-    if (i->_category == Arg::cat_rc ||
-        i->_category == Arg::cat_override)
-    {
-      if (i != context.a3.begin ())
-        permanent_overrides += " ";
-
-      permanent_overrides += i->_raw;
-    }
-  }
-
-  std::vector <std::string> quit_commands;
-  quit_commands.push_back ("quit");
-  quit_commands.push_back ("exit");
-  quit_commands.push_back ("bye");
-
-  std::string command;
-  bool keepGoing = true;
-
-  do
-  {
-    std::cout << context.config.get ("shell.prompt") << " ";
-
-    command = "";
-    std::getline (std::cin, command);
-    std::string decoratedCommand = "task " + trim (command + permanent_overrides);
-
-    // When looking for the 'quit' command, use 'command', not
-    // 'decoratedCommand'.
-    if (std::find (quit_commands.begin (), quit_commands.end (), lowerCase (command)) != quit_commands.end ())
-    {
-      keepGoing = false;
-    }
-    else
-    {
-      try
-      {
-        context.clear ();
-
-        std::vector <std::string> args;
-        split (args, decoratedCommand, ' ');
-        std::vector <std::string>::iterator arg;
-        for (arg = args.begin (); arg != args.end (); ++arg)
-          context.a3.capture (*arg);
-
-        context.initialize (0, NULL);
-        context.run ();
-      }
-
-      catch (const std::string& error)
-      {
-        std::cerr << error << "\n";
-      }
-
-      catch (...)
-      {
-        std::cerr << STRING_UNKNOWN_ERROR << "\n";
-      }
-    }
-  }
-  while (keepGoing && !std::cin.eof ());
-
-  // No need to repeat any overrides after the shell quits.
-  context.clearMessages ();
-  return 0;
-}
-
-////////////////////////////////////////////////////////////////////////////////

src/shell/Readline.cpp

@@ -0,0 +1,72 @@
+////////////////////////////////////////////////////////////////////////////////
+// taskwarrior - a command line task list manager.
+//
+// Copyright 2006-2012, Paul Beckingham, Federico Hernandez.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+// http://www.opensource.org/licenses/mit-license.php
+//
+////////////////////////////////////////////////////////////////////////////////
+
+#define L10N                                           // Localization complete.
+
+#include <Readline.h>
+
+////////////////////////////////////////////////////////////////////////////////
+std::string Readline::gets (const std::string& prompt)
+{
+  // Get a line from the user.
+  char *line_read = rl::readline (prompt.c_str ());
+
+  // If the line has any text in it, save it on the history.
+  if (line_read && *line_read)
+    rl::add_history (line_read);
+
+  std::string ret (line_read);
+  free (line_read);
+
+  return ret;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+Wordexp::Wordexp (const std::string &str)
+{
+  wordexp (str.c_str (), &_p, 0);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+Wordexp::~Wordexp ()
+{
+  wordfree(&_p);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+int Wordexp::argc ()
+{
+  return _p.we_wordc;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+char** Wordexp::argv ()
+{
+  return _p.we_wordv;
+}
+
+////////////////////////////////////////////////////////////////////////////////

src/shell/Readline.h

@@ -25,18 +25,51 @@
 //
 ////////////////////////////////////////////////////////////////////////////////
 
-#ifndef INCLUDED_CMDSHELL
-#define INCLUDED_CMDSHELL
+#ifndef INCLUDED_READLINE
+#define INCLUDED_READLINE
 #define L10N                                           // Localization complete.
 
 #include <string>
-#include <Command.h>
+#include <stdio.h>
+#include <wordexp.h>
 
-class CmdShell : public Command
+namespace rl
+{
+  // Wrapping readline.h in a namespace to
+  // avoid cluttering the global namespace.
+  extern "C"
+  {
+    #include <readline/readline.h>
+    #include <readline/history.h>
+  }
+}
+
+// Static class that offers a C++ API to readline C functions.
+class Readline
 {
 public:
-  CmdShell ();
-  int execute (std::string&);
+  static std::string gets (const std::string& prompt);
+
+private:
+  // No construction or destruction.
+  Readline (); // Don't implement.
+  ~Readline (); // Don't implement.
+  Readline (const Readline&); // Don't implement.
+  Readline& operator= (const Readline&); // Don't implement.
+};
+
+// RAII for wordexp_t
+class Wordexp
+{
+public:
+  Wordexp (const std::string &str);
+  ~Wordexp ();
+
+  int argc ();
+  char** argv ();
+
+private:
+  wordexp_t _p;
 };
 
 #endif