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