modules/spawn-process.js

   1 /**
   2  * (C) Copyright 2007-2008 Jeremy Maitin-Shepard
   3  *
   4  * Use, modification, and distribution are subject to the terms specified in the
   5  * COPYING file.
   6 **/
   7
   8 in_module(null);
   9
  10 require("interactive.js");
  11 require("io.js");
  12 require("env.js");
  13
  14 function spawn_process_internal (program, args, blocking) {
  15     var process = Cc["@mozilla.org/process/util;1"]
  16         .createInstance(Ci.nsIProcess);
  17     process.init(find_file_in_path(program));
  18     return process.run(!!blocking, args, args.length);
  19 }
  20
  21 var PATH_programs = null;
  22 function get_shell_command_completer () {
  23     if (PATH_programs == null) {
  24         PATH_programs = [];
  25         var file = Cc["@mozilla.org/file/local;1"]
  26             .createInstance(Ci.nsILocalFile);
  27         for (var i = 0, plen = PATH.length; i < plen; ++i) {
  28             try {
  29                 file.initWithPath(PATH[i]);
  30                 var entries = file.directoryEntries;
  31                 while (entries.hasMoreElements()) {
  32                     var entry = entries.getNext().QueryInterface(Ci.nsIFile);
  33                     PATH_programs.push(entry.leafName);
  34                 }
  35             } catch (e) {}
  36         }
  37         PATH_programs.sort();
  38     }
  39     return prefix_completer($completions = PATH_programs,
  40                             $get_string = function (x) x);
  41 }
  42
  43 // use default
  44 minibuffer_auto_complete_preferences["shell-command"] = null;
  45
  46 /* FIXME: support a relative or full path as well as PATH commands */
  47 define_keywords("$cwd");
  48 minibuffer.prototype.read_shell_command = function () {
  49     keywords(arguments, $history = "shell-command");
  50     var prompt = arguments.$prompt || "Shell command [" + arguments.$cwd.path + "]:";
  51     var result = yield this.read(
  52         $prompt = prompt,
  53         $history = "shell-command",
  54         $auto_complete = "shell-command",
  55         $select,
  56         $validator = function (x, m) {
  57             var s = x.replace(/^\s+|\s+$/g, '');
  58             if (s.length == 0) {
  59                 m.message("A blank shell command is not allowed.");
  60                 return false;
  61             }
  62             return true;
  63         },
  64         forward_keywords(arguments),
  65         $completer = get_shell_command_completer());
  66     yield co_return(result);
  67 }
  68
  69 function find_spawn_helper () {
  70     var f = file_locator_service.get("CurProcD", Ci.nsIFile);
  71     f.append("conkeror-spawn-helper");
  72     if (f.exists())
  73         return f;
  74     return find_file_in_path("conkeror-spawn-helper");
  75 }
  76
  77 const STDIN_FILENO = 0;
  78 const STDOUT_FILENO = 1;
  79 const STDERR_FILENO = 2;
  80
  81 var spawn_process_helper_default_fd_wait_timeout = 1000;
  82 var spawn_process_helper_setup_timeout = 2000;
  83
  84 /**
  85  * @param program_name
  86  *        Specifies the full path to the program.
  87  * @param args
  88  *        An array of strings to pass as the arguments to the program.  The
  89  *        first argument should be the program name.  These strings must not
  90  *        have any NUL bytes in them.
  91  * @param working_dir
  92  *        If non-null, must be an nsILocalFile.  spawn_process will switch
  93  *        to this path before running the program.
  94  * @param finished_callback
  95  *        Called with a single argument, the exit code of the process, as
  96  *        returned by the wait system call.
  97  * @param failure_callback
  98  *        Called with a single argument, an exception, if one occurs.
  99  * @param fds
 100  *        If non-null, must be an object with only non-negative integer
 101  *        properties set.  Each such property specifies that the corresponding
 102  *        file descriptor in the spawned process should be redirected.  Note
 103  *        that 0 corresponds to STDIN, 1 corresponds to STDOUT, and 2
 104  *        corresponds to STDERR.  Note that every redirected file descriptor can
 105  *        be used for both input and output, although STDIN, STDOUT, and STDERR
 106  *        are typically used only unidirectionally.  Each property must be an
 107  *        object itself, with an input and/or output property specifying
 108  *        callback functions that are called with an nsIAsyncInputStream or
 109  *        nsIAsyncOutputStream when the stream for that file descriptor is
 110  *        available.
 111  * @param fd_wait_timeout
 112  *        Specifies the number of milliseconds to wait for the file descriptor
 113  *        redirection sockets to be closed after the control socket indicates
 114  *        the process has exited before they are closed forcefully.  A negative
 115  *        value means to wait indefinitely.  If fd_wait_timeout is null,
 116  *        spawn_process_helper_default_fd_wait_timeout is used instead.
 117  * @return
 118  *        A function that can be called to prematurely terminate the spawned
 119  *        process.
 120  */
 121 function spawn_process (program_name, args, working_dir,
 122                         success_callback, failure_callback, fds,
 123                         fd_wait_timeout) {
 124     var spawn_process_helper_program = find_spawn_helper();
 125     if (spawn_process_helper_program == null)
 126         throw new Error("Error spawning process: conkeror-spawn-helper not found");
 127     args = args.slice();
 128     if (args[0] == null)
 129         args[0] = (program_name instanceof Ci.nsIFile) ? program_name.path : program_name;
 130
 131     program_name = find_file_in_path(program_name).path;
 132
 133     const key_length = 100;
 134     const fd_spec_size = 15;
 135
 136     if (fds == null)
 137         fds = {};
 138
 139     if (fd_wait_timeout === undefined)
 140         fd_wait_timeout = spawn_process_helper_default_fd_wait_timeout;
 141
 142     var unregistered_transports = [];
 143     var registered_transports = [];
 144
 145     var server = null;
 146     var setup_timer = null;
 147
 148     const CONTROL_CONNECTED = 0;
 149     const CONTROL_SENDING_KEY = 1;
 150     const CONTROL_SENT_KEY = 2;
 151
 152     var control_state = CONTROL_CONNECTED;
 153     var terminate_pending = false;
 154
 155     var control_transport = null;
 156
 157     var control_binary_input_stream = null;
 158     var control_output_stream = null, control_input_stream = null;
 159     var exit_status = null;
 160
 161     var client_key = "";
 162     var server_key = "";
 163     // Make sure key does not have any 0 bytes in it.
 164     for (let i = 0; i < key_length; ++i)
 165         client_key += String.fromCharCode(Math.floor(Math.random() * 255) + 1);
 166
 167     // Make sure key does not have any 0 bytes in it.
 168     for (let i = 0; i < key_length; ++i)
 169         server_key += String.fromCharCode(Math.floor(Math.random() * 255) + 1);
 170
 171     var key_file_fd_data = "";
 172
 173     // This is the total number of redirected file descriptors.
 174     var total_client_fds = 0;
 175
 176     // This is the total number of redirected file descriptors that will use a socket connection.
 177     var total_fds = 0;
 178
 179     for (let i in fds) {
 180         if (fds.hasOwnProperty(i)) {
 181             if (fds[i] == null) {
 182                 delete fds[i];
 183                 continue;
 184             }
 185             key_file_fd_data += i + "\0";
 186             let fd = fds[i];
 187             if ('file' in fd) {
 188                 if (fd.perms == null)
 189                     fd.perms = 0666;
 190                 key_file_fd_data += fd.file + "\0" + fd.mode + "\0" + fd.perms + "\0";
 191                 delete fds[i]; // Remove it from fds, as we won't need to work with it anymore
 192             } else {
 193                 ++total_fds;
 194                 key_file_fd_data += "\0";
 195             }
 196             ++total_client_fds;
 197         }
 198     }
 199     var key_file_data = client_key + "\0" + server_key + "\0" + program_name + "\0" +
 200         (working_dir != null ? working_dir.path : "") + "\0" +
 201         args.length + "\0" +
 202         args.join("\0") + "\0" +
 203         total_client_fds + "\0" + key_file_fd_data;
 204
 205     function fail (e) {
 206         if (!terminate_pending) {
 207             terminate();
 208             if (failure_callback)
 209                 failure_callback(e);
 210         }
 211     }
 212
 213     function cleanup_server () {
 214         if (server) {
 215             server.close();
 216             server = null;
 217         }
 218         for (let i in unregistered_transports) {
 219             unregistered_transports[i].close(0);
 220             delete unregistered_transports[i];
 221         }
 222     }
 223
 224     function cleanup_fd_sockets () {
 225         for (let i in registered_transports) {
 226             registered_transports[i].transport.close(0);
 227             delete registered_transports[i];
 228         }
 229     }
 230
 231     function cleanup_control () {
 232         if (control_transport) {
 233             control_binary_input_stream.close();
 234             control_binary_input_stream = null;
 235             control_transport.close(0);
 236             control_transport = null;
 237             control_input_stream = null;
 238             control_output_stream = null;
 239         }
 240     }
 241
 242     function control_send_terminate () {
 243         control_input_stream = null;
 244         control_binary_input_stream.close();
 245         control_binary_input_stream = null;
 246         async_binary_write(control_output_stream, "\0", function () {
 247             control_output_stream = null;
 248             control_transport.close(0);
 249             control_transport = null;
 250         });
 251     }
 252
 253     function terminate () {
 254         if (terminate_pending)
 255             return exit_status;
 256         terminate_pending = true;
 257         if (setup_timer) {
 258             setup_timer.cancel();
 259             setup_timer = null;
 260         }
 261         cleanup_server();
 262         cleanup_fd_sockets();
 263         if (control_transport) {
 264             switch (control_state) {
 265             case CONTROL_SENT_KEY:
 266                 control_send_terminate();
 267                 break;
 268             case CONTROL_CONNECTED:
 269                 cleanup_control();
 270                 break;
 271                 /**
 272                  * case CONTROL_SENDING_KEY: in this case once the key
 273                  * is sent, the terminate_pending flag will be noticed
 274                  * and control_send_terminate will be called, so nothing
 275                  * more needs to be done here.
 276                  */
 277             }
 278         }
 279         return exit_status;
 280     }
 281
 282     function finished () {
 283         // Only call success_callback if terminate was not already called
 284         if (!terminate_pending) {
 285             terminate();
 286             if (success_callback)
 287                 success_callback(exit_status);
 288         }
 289     }
 290
 291     // Create server socket to listen for connections from the external helper program
 292     try {
 293         server = Cc['@mozilla.org/network/server-socket;1']
 294             .createInstance(Ci.nsIServerSocket);
 295
 296         var key_file = get_temporary_file("conkeror-spawn-helper-key.dat");
 297
 298         write_binary_file(key_file, key_file_data);
 299         server.init(-1 /* choose a port automatically */,
 300                     true /* bind to localhost only */,
 301                     -1 /* select backlog size automatically */);
 302
 303         setup_timer = call_after_timeout(function () {
 304             setup_timer = null;
 305             if (control_state != CONTROL_SENT_KEY)
 306                 fail("setup timeout");
 307         }, spawn_process_helper_setup_timeout);
 308
 309         function wait_for_fd_sockets () {
 310             var remaining_streams = total_fds * 2;
 311             var timer = null;
 312             function handler () {
 313                 if (remaining_streams != null) {
 314                     --remaining_streams;
 315                     if (remaining_streams == 0) {
 316                         if (timer)
 317                             timer.cancel();
 318                         finished();
 319                     }
 320                 }
 321             }
 322             for each (let f in registered_transports) {
 323                 input_stream_async_wait(f.input, handler, false /* wait for closure */);
 324                 output_stream_async_wait(f.output, handler, false /* wait for closure */);
 325             }
 326             if (fd_wait_timeout != null) {
 327                 timer = call_after_timeout(function() {
 328                     remaining_streams = null;
 329                     finished();
 330                 }, fd_wait_timeout);
 331             }
 332         }
 333
 334         var control_data = "";
 335
 336         function handle_control_input () {
 337             if (terminate_pending)
 338                 return;
 339             try {
 340                 let avail = control_input_stream.available();
 341                 if (avail > 0) {
 342                     control_data += control_binary_input_stream.readBytes(avail);
 343                     var off = control_data.indexOf("\0");
 344                     if (off >= 0) {
 345                         let message = control_data.substring(0,off);
 346                         exit_status = parseInt(message);
 347                         cleanup_control();
 348                         /* wait for all fd sockets to close? */
 349                         if (total_fds > 0)
 350                             wait_for_fd_sockets();
 351                         else
 352                             finished();
 353                         return;
 354                     }
 355                 }
 356                 input_stream_async_wait(control_input_stream, handle_control_input);
 357             } catch (e) {
 358                 // Control socket closed: terminate
 359                 cleanup_control();
 360                 fail(e);
 361             }
 362         }
 363
 364         var registered_fds = 0;
 365
 366         server.asyncListen(
 367             {
 368                 onSocketAccepted: function (server, transport) {
 369                     unregistered_transports.push(transport);
 370                     function remove_from_unregistered () {
 371                         var i;
 372                         i = unregistered_transports.indexOf(transport);
 373                         if (i >= 0) {
 374                             unregistered_transports.splice(i, 1);
 375                             return true;
 376                         }
 377                         return false;
 378                     }
 379                     function close () {
 380                         transport.close(0);
 381                         remove_from_unregistered();
 382                     }
 383                     var received_data = "";
 384                     var header_size = key_length + fd_spec_size;
 385
 386                     var in_stream, bin_stream, out_stream;
 387
 388                     function handle_input () {
 389                         if (terminate_pending)
 390                             return;
 391                         try {
 392                             let remaining = header_size - received_data.length;
 393                             let avail = in_stream.available();
 394                             if (avail > 0) {
 395                                 if (avail > remaining)
 396                                     avail = remaining;
 397                                 received_data += bin_stream.readBytes(avail);
 398                             }
 399                             if (received_data.length < header_size) {
 400                                 input_stream_async_wait(in_stream, handle_input);
 401                                 return;
 402                             } else {
 403                                 if (received_data.substring(0, key_length) != client_key)
 404                                     throw "Invalid key";
 405                             }
 406                         } catch (e) {
 407                             close();
 408                         }
 409                         try {
 410                             var fdspec = received_data.substring(key_length);
 411                             if (fdspec.charCodeAt(0) == 0) {
 412
 413                                 // This is the control connection
 414                                 if (control_transport)
 415                                     throw "Control transport already exists";
 416                                 control_transport = transport;
 417                                 control_output_stream = out_stream;
 418                                 control_input_stream = in_stream;
 419                                 control_binary_input_stream = bin_stream;
 420                                 remove_from_unregistered();
 421                             } else {
 422                                 var fd = parseInt(fdspec);
 423                                 if (!fds.hasOwnProperty(fd) || (fd in registered_transports))
 424                                     throw "Invalid fd";
 425                                 remove_from_unregistered();
 426                                 bin_stream = null;
 427                                 registered_transports[fd] = {transport: transport,
 428                                                              input: in_stream,
 429                                                              output: out_stream};
 430                                 ++registered_fds;
 431                             }
 432                             if (control_transport && registered_fds == total_fds) {
 433                                 cleanup_server();
 434                                 control_state = CONTROL_SENDING_KEY;
 435                                 async_binary_write(control_output_stream, server_key,
 436                                                    function (error) {
 437                                                        if (error != null)
 438                                                            fail(error);
 439                                                        control_state = CONTROL_SENT_KEY;
 440                                                        if (setup_timer) {
 441                                                            setup_timer.cancel();
 442                                                            setup_timer = null;
 443                                                        }
 444                                                        if (terminate_pending) {
 445                                                            control_send_terminate();
 446                                                        } else {
 447                                                            for (let i in fds) {
 448                                                                let f = fds[i];
 449                                                                let t = registered_transports[i];
 450                                                                if ('input' in f)
 451                                                                    f.input(t.input);
 452                                                                else
 453                                                                    t.input.close();
 454                                                                if ('output' in f)
 455                                                                    f.output(t.output);
 456                                                                else
 457                                                                    t.output.close();
 458                                                            }
 459                                                        }
 460                                                    });
 461                                 input_stream_async_wait(control_input_stream, handle_control_input);
 462                             }
 463                         } catch (e) {
 464                             fail(e);
 465                         }
 466                     }
 467
 468                     try {
 469                         in_stream = transport.openInputStream(Ci.nsITransport.OPEN_NON_BLOCKING, 0, 0);
 470                         out_stream = transport.openOutputStream(Ci.nsITransport.OPEN_NON_BLOCKING, 0, 0);
 471                         bin_stream = binary_input_stream(in_stream);
 472                         input_stream_async_wait(in_stream, handle_input);
 473                     } catch (e) {
 474                         close();
 475                     }
 476                 },
 477                 onStopListening: function (s, status) {
 478                 }
 479             });
 480
 481         spawn_process_internal(spawn_process_helper_program, [key_file.path, server.port], false);
 482         return terminate;
 483     } catch (e) {
 484         terminate();
 485
 486         if ((e instanceof Ci.nsIException) && e.result == Cr.NS_ERROR_INVALID_POINTER) {
 487             if (WINDOWS)
 488                 throw new Error("Error spawning process: not yet supported on MS Windows");
 489             else
 490                 throw new Error("Error spawning process: conkeror-spawn-helper not found");
 491         }
 492         // Allow the exception to propagate to the caller
 493         throw e;
 494     }
 495 }
 496
 497 /**
 498  * spawn_process_blind: spawn a process and forget about it
 499  */
 500 define_keywords("$cwd", "$fds");
 501 function spawn_process_blind (program_name, args) {
 502     keywords(arguments);
 503     /* Check if we can use spawn_process_internal */
 504     var cwd = arguments.$cwd;
 505     var fds = arguments.$fds;
 506     if (cwd == null && fds == null && args[0] == null)
 507         spawn_process_internal(program_name, args.slice(1));
 508     else {
 509         spawn_process(program_name, args, cwd,
 510                       null /* success callback */,
 511                       null /* failure callback */,
 512                       fds);
 513     }
 514 }
 515
 516
 517 //  Keyword arguments: $cwd, $fds
 518 function spawn_and_wait_for_process (program_name, args) {
 519     keywords(arguments, $cwd = null, $fds = null);
 520     var cc = yield CONTINUATION;
 521     spawn_process(program_name, args, arguments.$cwd,
 522                   cc, cc.throw,
 523                   arguments.$fds);
 524     var result = yield SUSPEND;
 525     yield co_return(result);
 526 }
 527
 528 // Keyword arguments: $cwd, $fds
 529 function shell_command_blind (cmd) {
 530     keywords(arguments);
 531     /* Check if we can use spawn_process_internal */
 532     var cwd = arguments.$cwd;
 533     var fds = arguments.$fds;
 534
 535     var program_name;
 536     var args;
 537
 538     if (POSIX) {
 539         var full_cmd;
 540         if (cwd)
 541             full_cmd = "cd \"" + shell_quote(cwd.path) + "\"; " + cmd;
 542         else
 543             full_cmd = cmd;
 544         program_name = getenv("SHELL") || "/bin/sh";
 545         args = [null, "-c", full_cmd];
 546     } else {
 547         var full_cmd;
 548         if (cwd) {
 549             full_cmd = "";
 550             if (cwd.path.match(/[a-z]:/i)) {
 551                 full_cmd += cwd.path.substring(0,2) + " && ";
 552             }
 553             full_cmd += "cd \"" + shell_quote(cwd.path) + "\" && " + cmd;
 554         } else
 555             full_cmd = cmd;
 556
 557         /* Need to convert the single command-line into a list of
 558             * arguments that will then get converted back into a *
 559             command-line by Mozilla. */
 560         var out = [null, "/C"];
 561         var cur_arg = "";
 562         var quoting = false;
 563         for (var i = 0; i < full_cmd.length; ++i) {
 564             var ch = full_cmd[i];
 565             if (ch == " ") {
 566                 if (quoting) {
 567                     cur_arg += ch;
 568                 } else {
 569                     out.push(cur_arg);
 570                     cur_arg = "";
 571                 }
 572                 continue;
 573             }
 574             if (ch == "\"") {
 575                 quoting = !quoting;
 576                 continue;
 577             }
 578             cur_arg += ch;
 579         }
 580         if (cur_arg.length > 0)
 581             out.push(cur_arg);
 582         program_name = "cmd.exe";
 583         args = out;
 584     }
 585     spawn_process_blind(program_name, args, $fds = arguments.$fds);
 586 }
 587
 588 function substitute_shell_command_argument (cmdline, argument) {
 589     if (!cmdline.match("{}"))
 590         return cmdline + " \"" + shell_quote(argument) + "\"";
 591     else
 592         return cmdline.replace("{}", "\"" + shell_quote(argument) + "\"");
 593 }
 594
 595 function shell_command_with_argument_blind (command, arg) {
 596     shell_command_blind(substitute_shell_command_argument(command, arg), forward_keywords(arguments));
 597 }
 598
 599 /**
 600  * Keyword arguments:
 601  * $cwd: The current working directory for the process.
 602  * $fds: File descriptors to use.
 603  */
 604 function shell_command (command) {
 605     if (!POSIX)
 606         throw new Error("shell_command: Your OS is not yet supported");
 607     var result = yield spawn_and_wait_for_process(getenv("SHELL") || "/bin/sh",
 608                                                   [null, "-c", command],
 609                                                   forward_keywords(arguments));
 610     yield co_return(result);
 611 }
 612
 613 function shell_command_with_argument (command, arg) {
 614     yield co_return((yield shell_command(substitute_shell_command_argument(command, arg), forward_keywords(arguments))));
 615 }
 616
 617 provide("spawn-process");