src/dinitctl.cc

   1 #include <cstdio>
   2 #include <cstddef>
   3 #include <cstring>
   4 #include <string>
   5 #include <iostream>
   6 #include <fstream>
   7 #include <system_error>
   8 #include <memory>
   9 #include <algorithm>
  10
  11 #include <sys/types.h>
  12 #include <sys/stat.h>
  13 #include <sys/wait.h>
  14 #include <sys/socket.h>
  15 #include <sys/un.h>
  16 #include <unistd.h>
  17 #include <signal.h>
  18 #include <pwd.h>
  19
  20 #include "control-cmds.h"
  21 #include "service-constants.h"
  22 #include "cpbuffer.h"
  23 #include "dinit-client.h"
  24 #include "load-service.h"
  25 #include "dinit-util.h"
  26 #include "mconfig.h"
  27
  28 // dinitctl:  utility to control the Dinit daemon, including starting and stopping of services.
  29
  30 // This utility communicates with the dinit daemon via a unix stream socket (as specified in
  31 // SYSCONTROLSOCKET, or $HOME/.dinitctl).
  32
  33 static constexpr uint16_t min_cp_version = 1;
  34 static constexpr uint16_t max_cp_version = 1;
  35
  36 enum class command_t;
  37
  38 static int issue_load_service(int socknum, const char *service_name, bool find_only = false);
  39 static int check_load_reply(int socknum, cpbuffer_t &, handle_t *handle_p, service_state_t *state_p);
  40 static int start_stop_service(int socknum, cpbuffer_t &, const char *service_name, command_t command,
  41         bool do_pin, bool do_force, bool wait_for_service, bool verbose);
  42 static int unpin_service(int socknum, cpbuffer_t &, const char *service_name, bool verbose);
  43 static int unload_service(int socknum, cpbuffer_t &, const char *service_name);
  44 static int list_services(int socknum, cpbuffer_t &);
  45 static int shutdown_dinit(int soclknum, cpbuffer_t &);
  46 static int add_remove_dependency(int socknum, cpbuffer_t &rbuffer, bool add, const char *service_from,
  47         const char *service_to, dependency_type dep_type);
  48 static int enable_disable_service(int socknum, cpbuffer_t &rbuffer, const char *from, const char *to,
  49         bool enable);
  50
  51 static const char * describeState(bool stopped)
  52 {
  53     return stopped ? "stopped" : "started";
  54 }
  55
  56 static const char * describeVerb(bool stop)
  57 {
  58     return stop ? "stop" : "start";
  59 }
  60
  61 enum class command_t {
  62     NONE,
  63     START_SERVICE,
  64     WAKE_SERVICE,
  65     STOP_SERVICE,
  66     RESTART_SERVICE,
  67     RELEASE_SERVICE,
  68     UNPIN_SERVICE,
  69     UNLOAD_SERVICE,
  70     LIST_SERVICES,
  71     SHUTDOWN,
  72     ADD_DEPENDENCY,
  73     RM_DEPENDENCY,
  74     ENABLE_SERVICE,
  75     DISABLE_SERVICE
  76 };
  77
  78
  79 // Entry point.
  80 int main(int argc, char **argv)
  81 {
  82     using namespace std;
  83
  84     bool show_help = argc < 2;
  85     const char *service_name = nullptr;
  86     const char *to_service_name = nullptr;
  87     dependency_type dep_type;
  88     bool dep_type_set = false;
  89
  90     std::string control_socket_str;
  91     const char * control_socket_path = nullptr;
  92
  93     bool verbose = true;
  94     bool sys_dinit = false;  // communicate with system daemon
  95     bool wait_for_service = true;
  96     bool do_pin = false;
  97     bool do_force = false;
  98
  99     command_t command = command_t::NONE;
 100
 101     for (int i = 1; i < argc; i++) {
 102         if (argv[i][0] == '-') {
 103             if (strcmp(argv[i], "--help") == 0) {
 104                 show_help = true;
 105                 break;
 106             }
 107             else if (strcmp(argv[i], "--no-wait") == 0) {
 108                 wait_for_service = false;
 109             }
 110             else if (strcmp(argv[i], "--quiet") == 0) {
 111                 verbose = false;
 112             }
 113             else if (strcmp(argv[i], "--system") == 0 || strcmp(argv[i], "-s") == 0) {
 114                 sys_dinit = true;
 115             }
 116             else if (strcmp(argv[i], "--pin") == 0) {
 117                 do_pin = true;
 118             }
 119             else if (strcmp(argv[i], "--socket-path") == 0 || strcmp(argv[i], "-p") == 0) {
 120                 ++i;
 121                 if (i == argc) {
 122                     cerr << "dinitctl: --socket-path/-p should be followed by socket path" << std::endl;
 123                     return 1;
 124                 }
 125                 control_socket_str = argv[i];
 126             }
 127             else if ((command == command_t::ENABLE_SERVICE || command == command_t::DISABLE_SERVICE)
 128                     && strcmp(argv[i], "--from") == 0) {
 129                 ++i;
 130                 if (i == argc) {
 131                     cerr << "dinitctl: --from should be followed by a service name" << std::endl;
 132                     return 1;
 133                 }
 134                 service_name = argv[i];
 135             }
 136             else if ((command == command_t::STOP_SERVICE || command == command_t::RESTART_SERVICE)
 137                     && (strcmp(argv[i], "--force") == 0 || strcmp(argv[i], "-f") == 0)) {
 138                 do_force = true;
 139             }
 140             else {
 141                 cerr << "dinitctl: unrecognized/invalid option: " << argv[i] << " (use --help for help)\n";
 142                 return 1;
 143             }
 144         }
 145         else if (command == command_t::NONE) {
 146             if (strcmp(argv[i], "start") == 0) {
 147                 command = command_t::START_SERVICE;
 148             }
 149             else if (strcmp(argv[i], "wake") == 0) {
 150                 command = command_t::WAKE_SERVICE;
 151             }
 152             else if (strcmp(argv[i], "stop") == 0) {
 153                 command = command_t::STOP_SERVICE;
 154             }
 155             else if (strcmp(argv[i], "restart") == 0) {
 156                 command = command_t::RESTART_SERVICE;
 157             }
 158             else if (strcmp(argv[i], "release") == 0) {
 159                 command = command_t::RELEASE_SERVICE;
 160             }
 161             else if (strcmp(argv[i], "unpin") == 0) {
 162                 command = command_t::UNPIN_SERVICE;
 163             }
 164             else if (strcmp(argv[i], "unload") == 0) {
 165                 command = command_t::UNLOAD_SERVICE;
 166             }
 167             else if (strcmp(argv[i], "list") == 0) {
 168                 command = command_t::LIST_SERVICES;
 169             }
 170             else if (strcmp(argv[i], "shutdown") == 0) {
 171                 command = command_t::SHUTDOWN;
 172             }
 173             else if (strcmp(argv[i], "add-dep") == 0) {
 174                 command = command_t::ADD_DEPENDENCY;
 175             }
 176             else if (strcmp(argv[i], "rm-dep") == 0) {
 177                 command = command_t::RM_DEPENDENCY;
 178             }
 179             else if (strcmp(argv[i], "enable") == 0) {
 180                 command = command_t::ENABLE_SERVICE;
 181             }
 182             else if (strcmp(argv[i], "disable") == 0) {
 183                 command = command_t::DISABLE_SERVICE;
 184             }
 185             else {
 186                 cerr << "dinitctl: unrecognized command: " << argv[i] << " (use --help for help)\n";
 187                 return 1;
 188             }
 189         }
 190         else {
 191             // service name / other non-option
 192             if (command == command_t::ADD_DEPENDENCY || command == command_t::RM_DEPENDENCY) {
 193                 if (! dep_type_set) {
 194                     if (strcmp(argv[i], "regular") == 0) {
 195                         dep_type = dependency_type::REGULAR;
 196                     }
 197                     else if (strcmp(argv[i], "milestone") == 0) {
 198                         dep_type = dependency_type::MILESTONE;
 199                     }
 200                     else if (strcmp(argv[i], "waits-for") == 0) {
 201                         dep_type = dependency_type::WAITS_FOR;
 202                     }
 203                     else {
 204                         show_help = true;
 205                         break;
 206                     }
 207                     dep_type_set = true;
 208                 }
 209                 else if (service_name == nullptr) {
 210                     service_name = argv[i];
 211                 }
 212                 else if (to_service_name == nullptr) {
 213                     to_service_name = argv[i];
 214                 }
 215                 else {
 216                     show_help = true;
 217                     break;
 218                 }
 219             }
 220             else if (command == command_t::ENABLE_SERVICE || command == command_t::DISABLE_SERVICE) {
 221                 if (to_service_name != nullptr) {
 222                     show_help = true;
 223                     break;
 224                 }
 225                 to_service_name = argv[i];
 226             }
 227             else {
 228                 if (service_name != nullptr) {
 229                     show_help = true;
 230                     break;
 231                 }
 232                 service_name = argv[i];
 233                 // TODO support multiple services
 234             }
 235         }
 236     }
 237
 238     bool no_service_cmd = (command == command_t::LIST_SERVICES || command == command_t::SHUTDOWN);
 239
 240     if (command == command_t::ENABLE_SERVICE || command == command_t::DISABLE_SERVICE) {
 241         show_help |= (to_service_name == nullptr);
 242     }
 243     else if ((service_name == nullptr && ! no_service_cmd) || command == command_t::NONE) {
 244         show_help = true;
 245     }
 246
 247     if (service_name != nullptr && no_service_cmd) {
 248         show_help = true;
 249     }
 250
 251     if ((command == command_t::ADD_DEPENDENCY || command == command_t::RM_DEPENDENCY)
 252             && (! dep_type_set || service_name == nullptr || to_service_name == nullptr)) {
 253         show_help = true;
 254     }
 255
 256     if (show_help) {
 257         cout << "dinitctl:   control Dinit services\n"
 258           "\n"
 259           "Usage:\n"
 260           "    dinitctl [options] start [options] <service-name>\n"
 261           "    dinitctl [options] stop [options] <service-name>\n"
 262           "    dinitctl [options] wake [options] <service-name>\n"
 263           "    dinitctl [options] release [options] <service-name>\n"
 264           "    dinitctl [options] unpin <service-name>\n"
 265           "    dinitctl [options] unload <service-name>\n"
 266           "    dinitctl [options] list\n"
 267           "    dinitctl [options] shutdown\n"
 268           "    dinitctl [options] add-dep <type> <from-service> <to-service>\n"
 269           "    dinitctl [options] rm-dep <type> <from-service> <to-service>\n"
 270           "    dinitctl [options] enable [--from <from-service>] <to-service>\n"
 271           "    dinitctl [options] disable [--from <from-service>] <to-service>\n"
 272           "\n"
 273           "Note: An activated service continues running when its dependents stop.\n"
 274           "\n"
 275           "General options:\n"
 276           "  --help           : show this help\n"
 277           "  -s, --system     : control system daemon instead of user daemon\n"
 278           "  --quiet          : suppress output (except errors)\n"
 279           "  --socket-path <path>, -p <path>\n"
 280           "                   : specify socket for communication with daemon\n"
 281           "\n"
 282           "Command options:\n"
 283           "  --no-wait        : don't wait for service startup/shutdown to complete\n"
 284           "  --pin            : pin the service in the requested state\n"
 285           "  --force          : force stop even if dependents will be affected\n";
 286         return 1;
 287     }
 288
 289     signal(SIGPIPE, SIG_IGN);
 290
 291     // Locate control socket
 292     if (! control_socket_str.empty()) {
 293         control_socket_path = control_socket_str.c_str();
 294     }
 295     else {
 296         control_socket_path = SYSCONTROLSOCKET; // default to system
 297         if (! sys_dinit) {
 298             char * userhome = getenv("HOME");
 299             if (userhome == nullptr) {
 300                 struct passwd * pwuid_p = getpwuid(getuid());
 301                 if (pwuid_p != nullptr) {
 302                     userhome = pwuid_p->pw_dir;
 303                 }
 304             }
 305
 306             if (userhome != nullptr) {
 307                 control_socket_str = userhome;
 308                 control_socket_str += "/.dinitctl";
 309                 control_socket_path = control_socket_str.c_str();
 310             }
 311             else {
 312                 cerr << "Cannot locate user home directory (set HOME or check /etc/passwd file)" << endl;
 313                 return 1;
 314             }
 315         }
 316     }
 317
 318     int socknum = socket(AF_UNIX, SOCK_STREAM, 0);
 319     if (socknum == -1) {
 320         perror("dinitctl: socket");
 321         return 1;
 322     }
 323
 324     struct sockaddr_un * name;
 325     uint sockaddr_size = offsetof(struct sockaddr_un, sun_path) + strlen(control_socket_path) + 1;
 326     name = (struct sockaddr_un *) malloc(sockaddr_size);
 327     if (name == nullptr) {
 328         cerr << "dinitctl: Out of memory" << endl;
 329         return 1;
 330     }
 331
 332     name->sun_family = AF_UNIX;
 333     strcpy(name->sun_path, control_socket_path);
 334
 335     int connr = connect(socknum, (struct sockaddr *) name, sockaddr_size);
 336     if (connr == -1) {
 337         perror("dinitctl: connect");
 338         return 1;
 339     }
 340
 341     try {
 342         // Start by querying protocol version:
 343         cpbuffer_t rbuffer;
 344         check_protocol_version(min_cp_version, max_cp_version, rbuffer, socknum);
 345
 346         if (command == command_t::UNPIN_SERVICE) {
 347             return unpin_service(socknum, rbuffer, service_name, verbose);
 348         }
 349         else if (command == command_t::UNLOAD_SERVICE) {
 350             return unload_service(socknum, rbuffer, service_name);
 351         }
 352         else if (command == command_t::LIST_SERVICES) {
 353             return list_services(socknum, rbuffer);
 354         }
 355         else if (command == command_t::SHUTDOWN) {
 356             return shutdown_dinit(socknum, rbuffer);
 357         }
 358         else if (command == command_t::ADD_DEPENDENCY || command == command_t::RM_DEPENDENCY) {
 359             return add_remove_dependency(socknum, rbuffer, command == command_t::ADD_DEPENDENCY,
 360                     service_name, to_service_name, dep_type);
 361         }
 362         else if (command == command_t::ENABLE_SERVICE || command == command_t::DISABLE_SERVICE) {
 363             // If only one service specified, assume that we enable for 'boot' service:
 364             if (service_name == nullptr) {
 365                 service_name = "boot";
 366             }
 367             return enable_disable_service(socknum, rbuffer, service_name, to_service_name,
 368                     command == command_t::ENABLE_SERVICE);
 369         }
 370         else {
 371             return start_stop_service(socknum, rbuffer, service_name, command, do_pin, do_force,
 372                     wait_for_service, verbose);
 373         }
 374     }
 375     catch (cp_old_client_exception &e) {
 376         std::cerr << "dinitctl: too old (server reports newer protocol version)" << std::endl;
 377         return 1;
 378     }
 379     catch (cp_old_server_exception &e) {
 380         std::cerr << "dinitctl: server too old or protocol error" << std::endl;
 381         return 1;
 382     }
 383     catch (cp_read_exception &e) {
 384         cerr << "dinitctl: control socket read failure or protocol error" << endl;
 385         return 1;
 386     }
 387     catch (cp_write_exception &e) {
 388         cerr << "dinitctl: control socket write error: " << std::strerror(e.errcode) << endl;
 389         return 1;
 390     }
 391 }
 392
 393 // Extract/read a string of specified length from the buffer/socket. The string is consumed
 394 // from the buffer.
 395 static std::string read_string(int socknum, cpbuffer_t &rbuffer, uint32_t length)
 396 {
 397     int rb_len = rbuffer.get_length();
 398     if (uint32_t(rb_len) >= length) {
 399         std::string r = rbuffer.extract_string(0, length);
 400         rbuffer.consume(length);
 401         return r;
 402     }
 403
 404     std::string r = rbuffer.extract_string(0, rb_len);
 405     uint32_t rlen = length - rb_len;
 406     uint32_t clen;
 407     do {
 408         rbuffer.reset();
 409         rbuffer.fill(socknum);
 410         char *bptr = rbuffer.get_ptr(0);
 411         clen = rbuffer.get_length();
 412         clen = std::min(clen, rlen);
 413         r.append(bptr, clen);
 414         rlen -= clen;
 415     } while (rlen > 0);
 416
 417     rbuffer.consume(clen);
 418
 419     return r;
 420 }
 421
 422 // Load a service: issue load command, wait for reply. Return true on success, display error message
 423 // and return false on failure.
 424 //      socknum  - the socket fd to communicate via
 425 //      rbuffer  - the buffer for communication
 426 //      name     - the name of the service to load
 427 //      handle   - where to store the handle of the loaded service
 428 //      state    - where to store the state of the loaded service (may be null).
 429 static bool load_service(int socknum, cpbuffer_t &rbuffer, const char *name, handle_t *handle,
 430         service_state_t *state)
 431 {
 432     // Load 'to' service:
 433     if (issue_load_service(socknum, name)) {
 434         return false;
 435     }
 436
 437     wait_for_reply(rbuffer, socknum);
 438
 439     if (check_load_reply(socknum, rbuffer, handle, state) != 0) {
 440         return false;
 441     }
 442
 443     return true;
 444 }
 445
 446 // Get the service name for a given handle, by querying the daemon.
 447 static std::string get_service_name(int socknum, cpbuffer_t &rbuffer, handle_t handle)
 448 {
 449     auto m = membuf()
 450             .append((char) DINIT_CP_QUERYSERVICENAME)
 451             .append((char) 0)
 452             .append(handle);
 453     write_all_x(socknum, m);
 454
 455     wait_for_reply(rbuffer, socknum);
 456
 457     if (rbuffer[0] != DINIT_RP_SERVICENAME) {
 458         throw cp_read_exception{0};
 459     }
 460
 461     // 1 byte reserved
 462     // uint16_t size
 463     fill_buffer_to(rbuffer, socknum, 2 + sizeof(uint16_t));
 464     uint16_t namesize;
 465     rbuffer.extract(&namesize, 2, sizeof(uint16_t));
 466     rbuffer.consume(2 + sizeof(uint16_t));
 467
 468     std::string name;
 469
 470     do {
 471         if (rbuffer.get_length() == 0) {
 472             rbuffer.fill(socknum);
 473         }
 474
 475         size_t to_extract = std::min(size_t(rbuffer.get_length()), namesize - name.length());
 476         size_t contiguous_len = rbuffer.get_contiguous_length(rbuffer.get_ptr(0));
 477         if (contiguous_len <= to_extract) {
 478             name.append(rbuffer.get_ptr(0), contiguous_len);
 479             rbuffer.consume(contiguous_len);
 480             name.append(rbuffer.get_ptr(0), to_extract - contiguous_len);
 481             rbuffer.consume(to_extract - contiguous_len);
 482         }
 483         else {
 484             name.append(rbuffer.get_ptr(0), to_extract);
 485             rbuffer.consume(to_extract);
 486             break;
 487         }
 488
 489     } while (name.length() < namesize);
 490
 491     return name;
 492 }
 493
 494 // Start/stop a service
 495 static int start_stop_service(int socknum, cpbuffer_t &rbuffer, const char *service_name,
 496         command_t command, bool do_pin, bool do_force, bool wait_for_service, bool verbose)
 497 {
 498     using namespace std;
 499
 500     bool do_stop = (command == command_t::STOP_SERVICE || command == command_t::RELEASE_SERVICE);
 501
 502     service_state_t state;
 503     handle_t handle;
 504
 505     if (! load_service(socknum, rbuffer, service_name, &handle, &state)) {
 506         return 1;
 507     }
 508
 509     service_state_t wanted_state = do_stop ? service_state_t::STOPPED : service_state_t::STARTED;
 510     int pcommand = 0;
 511     switch (command) {
 512         case command_t::STOP_SERVICE:
 513         case command_t::RESTART_SERVICE:  // stop, and then start
 514             pcommand = DINIT_CP_STOPSERVICE;
 515             break;
 516         case command_t::RELEASE_SERVICE:
 517             pcommand = DINIT_CP_RELEASESERVICE;
 518             break;
 519         case command_t::START_SERVICE:
 520             pcommand = DINIT_CP_STARTSERVICE;
 521             break;
 522         case command_t::WAKE_SERVICE:
 523             pcommand = DINIT_CP_WAKESERVICE;
 524             break;
 525         default: ;
 526     }
 527
 528     // Need to issue STOPSERVICE/STARTSERVICE
 529     // We'll do this regardless of the current service state / target state, since issuing
 530     // start/stop also sets or clears the "explicitly started" flag on the service.
 531     {
 532         char flags = (do_pin ? 1 : 0) | ((pcommand == DINIT_CP_STOPSERVICE && !do_force) ? 2 : 0);
 533         if (command == command_t::RESTART_SERVICE) {
 534             flags |= 4;
 535         }
 536
 537         auto m = membuf()
 538                 .append((char) pcommand)
 539                 .append(flags)
 540                 .append(handle);
 541         write_all_x(socknum, m);
 542
 543         wait_for_reply(rbuffer, socknum);
 544         auto reply_pkt_h = rbuffer[0];
 545         rbuffer.consume(1); // consume header
 546         if (reply_pkt_h == DINIT_RP_ALREADYSS) {
 547             bool already = (state == wanted_state);
 548             if (verbose) {
 549                 cout << "Service " << (already ? "(already) " : "")
 550                         << describeState(do_stop) << "." << endl;
 551             }
 552             return 0; // success!
 553         }
 554         if (reply_pkt_h == DINIT_RP_DEPENDENTS && pcommand == DINIT_CP_STOPSERVICE) {
 555             cerr << "dinitctl: cannot stop service due to the following dependents:\n";
 556             if (command != command_t::RESTART_SERVICE) {
 557                 cerr << "(Only direct dependents are listed. Exercise caution before using '--force' !!)\n";
 558             }
 559             // size_t number, N * handle_t handles
 560             size_t number;
 561             rbuffer.fill_to(socknum, sizeof(number));
 562             rbuffer.extract(&number, 0, sizeof(number));
 563             rbuffer.consume(sizeof(number));
 564             std::vector<handle_t> handles;
 565             handles.reserve(number);
 566             for (size_t i = 0; i < number; i++) {
 567                 handle_t handle;
 568                 rbuffer.fill_to(socknum, sizeof(handle_t));
 569                 rbuffer.extract(&handle, 0, sizeof(handle));
 570                 handles.push_back(handle);
 571                 rbuffer.consume(sizeof(handle));
 572             }
 573             // Print the directly affected dependents:
 574             cerr << " ";
 575             for (handle_t handle : handles) {
 576                 cerr << " " << get_service_name(socknum, rbuffer, handle);
 577             }
 578             cerr << "\n";
 579             return 1;
 580         }
 581         if (reply_pkt_h == DINIT_RP_NAK && command == command_t::RESTART_SERVICE) {
 582             cerr << "dinitctl: cannot restart service; service not started.\n";
 583             return 1;
 584         }
 585         if (reply_pkt_h == DINIT_RP_NAK && command == command_t::START_SERVICE) {
 586             cerr << "dinitctl: cannot start service (during shut down).\n";
 587             return 1;
 588         }
 589         if (reply_pkt_h == DINIT_RP_NAK && command == command_t::WAKE_SERVICE) {
 590             cerr << "dinitctl: service has no active dependents (or system is shutting down), cannot wake.\n";
 591             return 1;
 592         }
 593         if (reply_pkt_h != DINIT_RP_ACK && reply_pkt_h != DINIT_RP_ALREADYSS) {
 594             cerr << "dinitctl: protocol error." << endl;
 595             return 1;
 596         }
 597     }
 598
 599     if (! wait_for_service) {
 600         if (verbose) {
 601             cout << "Issued " << describeVerb(do_stop) << " command successfully." << endl;
 602         }
 603         return 0;
 604     }
 605
 606     service_event_t completionEvent;
 607     service_event_t cancelledEvent;
 608
 609     if (do_stop) {
 610         completionEvent = service_event_t::STOPPED;
 611         cancelledEvent = service_event_t::STOPCANCELLED;
 612     }
 613     else {
 614         completionEvent = service_event_t::STARTED;
 615         cancelledEvent = service_event_t::STARTCANCELLED;
 616     }
 617
 618     // Wait until service started:
 619     int r = rbuffer.fill_to(socknum, 2);
 620     while (r > 0) {
 621         if (rbuffer[0] >= 100) {
 622             int pktlen = (unsigned char) rbuffer[1];
 623             fill_buffer_to(rbuffer, socknum, pktlen);
 624
 625             if (rbuffer[0] == DINIT_IP_SERVICEEVENT) {
 626                 handle_t ev_handle;
 627                 rbuffer.extract((char *) &ev_handle, 2, sizeof(ev_handle));
 628                 service_event_t event = static_cast<service_event_t>(rbuffer[2 + sizeof(ev_handle)]);
 629                 if (ev_handle == handle) {
 630                     if (event == completionEvent) {
 631                         if (verbose) {
 632                             cout << "Service " << describeState(do_stop) << "." << endl;
 633                         }
 634                         return 0;
 635                     }
 636                     else if (event == cancelledEvent) {
 637                         if (verbose) {
 638                             cout << "Service " << describeVerb(do_stop) << " cancelled." << endl;
 639                         }
 640                         return 1;
 641                     }
 642                     else if (! do_stop && event == service_event_t::FAILEDSTART) {
 643                         if (verbose) {
 644                             cout << "Service failed to start." << endl;
 645                         }
 646                         return 1;
 647                     }
 648                 }
 649             }
 650
 651             rbuffer.consume(pktlen);
 652             r = rbuffer.fill_to(socknum, 2);
 653         }
 654         else {
 655             // Not an information packet?
 656             cerr << "dinitctl: protocol error" << endl;
 657             return 1;
 658         }
 659     }
 660
 661     if (r == -1) {
 662         perror("dinitctl: read");
 663     }
 664     else {
 665         cerr << "protocol error (connection closed by server)" << endl;
 666     }
 667     return 1;
 668 }
 669
 670 // Issue a "load service" command (DINIT_CP_LOADSERVICE), without waiting for
 671 // a response. Returns 1 on failure (with error logged), 0 on success.
 672 static int issue_load_service(int socknum, const char *service_name, bool find_only)
 673 {
 674     // Build buffer;
 675     uint16_t sname_len = strlen(service_name);
 676     int bufsize = 3 + sname_len;
 677
 678     std::unique_ptr<char[]> ubuf(new char[bufsize]);
 679     auto buf = ubuf.get();
 680
 681     buf[0] = find_only ? DINIT_CP_FINDSERVICE : DINIT_CP_LOADSERVICE;
 682     memcpy(buf + 1, &sname_len, 2);
 683     memcpy(buf + 3, service_name, sname_len);
 684
 685     write_all_x(socknum, buf, bufsize);
 686
 687     return 0;
 688 }
 689
 690 // Check that a "load service" reply was received, and that the requested service was found.
 691 //   state_p may be null.
 692 static int check_load_reply(int socknum, cpbuffer_t &rbuffer, handle_t *handle_p, service_state_t *state_p)
 693 {
 694     using namespace std;
 695
 696     if (rbuffer[0] == DINIT_RP_SERVICERECORD) {
 697         fill_buffer_to(rbuffer, socknum, 2 + sizeof(*handle_p));
 698         rbuffer.extract((char *) handle_p, 2, sizeof(*handle_p));
 699         if (state_p) *state_p = static_cast<service_state_t>(rbuffer[1]);
 700         //target_state = static_cast<service_state_t>(rbuffer[2 + sizeof(handle)]);
 701         rbuffer.consume(3 + sizeof(*handle_p));
 702         return 0;
 703     }
 704     else if (rbuffer[0] == DINIT_RP_NOSERVICE) {
 705         cerr << "dinitctl: failed to find/load service." << endl;
 706         return 1;
 707     }
 708     else {
 709         cerr << "dinitctl: protocol error." << endl;
 710         return 1;
 711     }
 712 }
 713
 714 static int unpin_service(int socknum, cpbuffer_t &rbuffer, const char *service_name, bool verbose)
 715 {
 716     using namespace std;
 717
 718     handle_t handle;
 719
 720     // Build buffer;
 721     if (! load_service(socknum, rbuffer, service_name, &handle, nullptr)) {
 722         return 1;
 723     }
 724
 725     // Issue UNPIN command.
 726     {
 727         auto m = membuf()
 728                 .append<char>(DINIT_CP_UNPINSERVICE)
 729                 .append(handle);
 730         write_all_x(socknum, m);
 731
 732         wait_for_reply(rbuffer, socknum);
 733         if (rbuffer[0] != DINIT_RP_ACK) {
 734             cerr << "dinitctl: protocol error." << endl;
 735             return 1;
 736         }
 737         rbuffer.consume(1);
 738     }
 739
 740     if (verbose) {
 741         cout << "Service unpinned." << endl;
 742     }
 743     return 0;
 744 }
 745
 746 static int unload_service(int socknum, cpbuffer_t &rbuffer, const char *service_name)
 747 {
 748     using namespace std;
 749
 750     if (issue_load_service(socknum, service_name, true) == 1) {
 751         return 1;
 752     }
 753
 754     wait_for_reply(rbuffer, socknum);
 755
 756     handle_t handle;
 757
 758     if (rbuffer[0] == DINIT_RP_NOSERVICE) {
 759         cerr << "dinitctl: service not loaded." << endl;
 760         return 1;
 761     }
 762
 763     if (check_load_reply(socknum, rbuffer, &handle, nullptr) != 0) {
 764         return 1;
 765     }
 766
 767     // Issue UNLOAD command.
 768     {
 769         auto m = membuf()
 770                 .append<char>(DINIT_CP_UNLOADSERVICE)
 771                 .append(handle);
 772         write_all_x(socknum, m);
 773
 774         wait_for_reply(rbuffer, socknum);
 775         if (rbuffer[0] == DINIT_RP_NAK) {
 776             cerr << "dinitctl: Could not unload service; service not stopped, or is a dependency of "
 777                     "other service." << endl;
 778             return 1;
 779         }
 780         if (rbuffer[0] != DINIT_RP_ACK) {
 781             cerr << "dinitctl: Protocol error." << endl;
 782             return 1;
 783         }
 784         rbuffer.consume(1);
 785     }
 786
 787     cout << "Service unloaded." << endl;
 788     return 0;
 789 }
 790
 791 static int list_services(int socknum, cpbuffer_t &rbuffer)
 792 {
 793     using namespace std;
 794
 795     char cmdbuf[] = { (char)DINIT_CP_LISTSERVICES };
 796     write_all_x(socknum, cmdbuf, 1);
 797
 798     wait_for_reply(rbuffer, socknum);
 799     while (rbuffer[0] == DINIT_RP_SVCINFO) {
 800         int hdrsize = 8 + std::max(sizeof(int), sizeof(pid_t));
 801         fill_buffer_to(rbuffer, socknum, hdrsize);
 802         int nameLen = rbuffer[1];
 803         service_state_t current = static_cast<service_state_t>(rbuffer[2]);
 804         service_state_t target = static_cast<service_state_t>(rbuffer[3]);
 805
 806         int console_flags = rbuffer[4];
 807         bool has_console = (console_flags & 2) != 0;
 808         bool waiting_console = (console_flags & 1) != 0;
 809         bool was_skipped = (console_flags & 4) != 0;
 810
 811         stopped_reason_t stop_reason = static_cast<stopped_reason_t>(rbuffer[5]);
 812
 813         pid_t service_pid;
 814         int exit_status;
 815         if (current != service_state_t::STOPPED) {
 816             rbuffer.extract((char *)&service_pid, 8, sizeof(service_pid));
 817         }
 818         else {
 819                 rbuffer.extract((char *)&exit_status, 8, sizeof(exit_status));
 820         }
 821
 822         fill_buffer_to(rbuffer, socknum, nameLen + hdrsize);
 823
 824         char *name_ptr = rbuffer.get_ptr(hdrsize);
 825         int clength = std::min(rbuffer.get_contiguous_length(name_ptr), nameLen);
 826
 827         string name = string(name_ptr, clength);
 828         name.append(rbuffer.get_buf_base(), nameLen - clength);
 829
 830         cout << "[";
 831
 832         cout << (target  == service_state_t::STARTED ? "{" : " ");
 833         if (current == service_state_t::STARTED) {
 834             cout << (was_skipped ? "s" : "+");
 835         }
 836         else {
 837             cout << " ";
 838         }
 839         cout << (target  == service_state_t::STARTED ? "}" : " ");
 840
 841         if (current == service_state_t::STARTING) {
 842             cout << "<<";
 843         }
 844         else if (current == service_state_t::STOPPING) {
 845             cout << ">>";
 846         }
 847         else {
 848             cout << "  ";
 849         }
 850
 851         cout << (target  == service_state_t::STOPPED ? "{" : " ");
 852         if (current == service_state_t::STOPPED) {
 853             bool did_fail = false;
 854             if (stop_reason == stopped_reason_t::TERMINATED) {
 855                 if (!WIFEXITED(exit_status) || WEXITSTATUS(exit_status) != 0) {
 856                     did_fail = true;
 857                 }
 858             }
 859             else did_fail = (stop_reason != stopped_reason_t::NORMAL);
 860
 861             cout << (did_fail ? "X" : "-");
 862         }
 863         else {
 864                 cout << " ";
 865         }
 866         cout << (target == service_state_t::STOPPED ? "}" : " ");
 867
 868         cout << "] " << name;
 869
 870         if (current != service_state_t::STOPPED && service_pid != -1) {
 871                 cout << " (pid: " << service_pid << ")";
 872         }
 873
 874         if (current == service_state_t::STOPPED && stop_reason == stopped_reason_t::TERMINATED) {
 875             if (WIFEXITED(exit_status)) {
 876                 cout << " (exit status: " << WEXITSTATUS(exit_status) << ")";
 877             }
 878             else if (WIFSIGNALED(exit_status)) {
 879                 cout << " (signal: " << WTERMSIG(exit_status) << ")";
 880             }
 881         }
 882
 883         if (has_console) {
 884                 cout << " (has console)";
 885         }
 886         else if (waiting_console) {
 887                 cout << " (waiting for console)";
 888         }
 889
 890         cout << endl;
 891
 892         rbuffer.consume(hdrsize + nameLen);
 893         wait_for_reply(rbuffer, socknum);
 894     }
 895
 896     if (rbuffer[0] != DINIT_RP_LISTDONE) {
 897         cerr << "dinitctl: Control socket protocol error" << endl;
 898         return 1;
 899     }
 900
 901     return 0;
 902 }
 903
 904 static int add_remove_dependency(int socknum, cpbuffer_t &rbuffer, bool add,
 905         const char *service_from, const char *service_to, dependency_type dep_type)
 906 {
 907     using namespace std;
 908
 909     handle_t from_handle;
 910     handle_t to_handle;
 911
 912     if (! load_service(socknum, rbuffer, service_from, &from_handle, nullptr)
 913             || ! load_service(socknum, rbuffer, service_to, &to_handle, nullptr)) {
 914         return 1;
 915     }
 916
 917     auto m = membuf()
 918             .append<char>(add ? (char)DINIT_CP_ADD_DEP : (char)DINIT_CP_REM_DEP)
 919             .append(dep_type)
 920             .append(from_handle)
 921             .append(to_handle);
 922     write_all_x(socknum, m);
 923
 924     wait_for_reply(rbuffer, socknum);
 925
 926     // check reply
 927     if (rbuffer[0] == DINIT_RP_NAK) {
 928         cerr << "dinitctl: Could not add dependency: circular dependency or wrong state" << endl;
 929         return 1;
 930     }
 931     if (rbuffer[0] != DINIT_RP_ACK) {
 932         cerr << "dinitctl: Control socket protocol error" << endl;
 933         return 1;
 934     }
 935
 936     return 0;
 937 }
 938
 939 static int shutdown_dinit(int socknum, cpbuffer_t &rbuffer)
 940 {
 941     // TODO support no-wait option.
 942     using namespace std;
 943
 944     auto m = membuf()
 945             .append<char>(DINIT_CP_SHUTDOWN)
 946             .append(static_cast<char>(shutdown_type_t::HALT));
 947     write_all_x(socknum, m);
 948
 949     wait_for_reply(rbuffer, socknum);
 950
 951     if (rbuffer[0] != DINIT_RP_ACK) {
 952         cerr << "dinitctl: Control socket protocol error" << endl;
 953         return 1;
 954     }
 955
 956     // Now wait for rollback complete, by waiting for the connection to close:
 957     try {
 958         while (true) {
 959             wait_for_info(rbuffer, socknum);
 960             rbuffer.consume(rbuffer[1]);
 961         }
 962     }
 963     catch (cp_read_exception &exc) {
 964         // Assume that the connection closed.
 965     }
 966
 967     return 0;
 968 }
 969
 970 // exception for cancelling a service operation
 971 class service_op_cancel { };
 972
 973 static int enable_disable_service(int socknum, cpbuffer_t &rbuffer, const char *from, const char *to,
 974         bool enable)
 975 {
 976     using namespace std;
 977
 978     service_state_t from_state = service_state_t::STARTED;
 979     handle_t from_handle;
 980
 981     handle_t to_handle;
 982
 983     if (! load_service(socknum, rbuffer, from, &from_handle, &from_state)
 984             || ! load_service(socknum, rbuffer, to, &to_handle, nullptr)) {
 985         return 1;
 986     }
 987
 988     // Get service load path
 989     char buf[1] = { DINIT_CP_QUERY_LOAD_MECH };
 990     write_all_x(socknum, buf, 1);
 991
 992     wait_for_reply(rbuffer, socknum);
 993
 994     if (rbuffer[0] != DINIT_RP_LOADER_MECH) {
 995         cerr << "dinitctl: Control socket protocol error" << endl;
 996         return 1;
 997     }
 998
 999     // Packet type, load mechanism type, packet size:
1000     fill_buffer_to(rbuffer, socknum, 2 + sizeof(uint32_t));
1001
1002     if (rbuffer[1] != SSET_TYPE_DIRLOAD) {
1003         cerr << "dinitctl: unknown configuration, unable to load service descriptions" << endl;
1004         return 1;
1005     }
1006
1007     vector<string> paths;
1008
1009     uint32_t pktsize;
1010     rbuffer.extract(&pktsize, 2, sizeof(uint32_t));
1011
1012     fill_buffer_to(rbuffer, socknum, 2 + sizeof(uint32_t) * 3); // path entries, cwd length
1013
1014     uint32_t path_entries;  // number of service directories
1015     rbuffer.extract(&path_entries, 2 + sizeof(uint32_t), sizeof(uint32_t));
1016
1017     uint32_t cwd_len;
1018     rbuffer.extract(&cwd_len, 2 + sizeof(uint32_t) * 2, sizeof(uint32_t));
1019     rbuffer.consume(2 + sizeof(uint32_t) * 3);
1020     pktsize -= 2 + sizeof(uint32_t) * 3;
1021
1022     // Read current working directory of daemon:
1023     std::string dinit_cwd = read_string(socknum, rbuffer, cwd_len);
1024
1025     // dinit daemon base directory against which service paths are resolved is in dinit_cwd
1026
1027     for (int i = 0; i < (int)path_entries; i++) {
1028         uint32_t plen;
1029         fill_buffer_to(rbuffer, socknum, sizeof(uint32_t));
1030         rbuffer.extract(&plen, 0, sizeof(uint32_t));
1031         rbuffer.consume(sizeof(uint32_t));
1032         paths.push_back(read_string(socknum, rbuffer, plen));
1033     }
1034
1035     // all service directories are now in the 'paths' vector
1036     // Load/read service description for 'from' service:
1037
1038     ifstream service_file;
1039     string service_file_path;
1040
1041     for (std::string path : paths) {
1042         string test_path = combine_paths(combine_paths(dinit_cwd, path.c_str()), from);
1043
1044         service_file.open(test_path.c_str(), ios::in);
1045         if (service_file) {
1046             service_file_path = test_path;
1047             break;
1048         }
1049     }
1050
1051     if (! service_file) {
1052         cerr << "dinitctl: could not locate service file for service '" << from << "'" << endl;
1053         return 1;
1054     }
1055
1056     // We now need to read the service file, identify the waits-for.d directory (bail out if more than one),
1057     // make sure the service is not listed as a dependency individually.
1058
1059     string waits_for_d;
1060
1061     try {
1062         process_service_file(from, service_file, [&](string &line, string &setting,
1063                 dinit_load::string_iterator i, dinit_load::string_iterator end) -> void {
1064             if (setting == "waits-for" || setting == "depends-on" || setting == "depends-ms") {
1065                 string dname = dinit_load::read_setting_value(i, end);
1066                 if (dname == to) {
1067                     // There is already a dependency
1068                     cerr << "dinitctl: there is a fixed dependency to service '" << to
1069                             << "' in the service description of '" << from << "'." << endl;
1070                     throw service_op_cancel();
1071                 }
1072             }
1073             else if (setting == "waits-for.d") {
1074                 string dname = dinit_load::read_setting_value(i, end);
1075                 if (! waits_for_d.empty()) {
1076                     cerr << "dinitctl: service '" << from << "' has multiple waits-for.d directories "
1077                             << "specified in service description" << endl;
1078                     throw service_op_cancel();
1079                 }
1080                 waits_for_d = std::move(dname);
1081             }
1082         });
1083     }
1084     catch (const service_op_cancel &cexc) {
1085         return 1;
1086     }
1087
1088     // If the from service has no waits-for.d specified, we can't continue
1089     if (waits_for_d.empty()) {
1090         cerr << "dinitctl: service '" << from << "' has no waits-for.d directory specified" << endl;
1091         return 1;
1092     }
1093
1094     // The waits-for.d path is relative to the service file path, combine:
1095     string waits_for_d_full = combine_paths(parent_path(service_file_path), waits_for_d.c_str());
1096
1097     // check if dependency already exists
1098     string dep_link_path = combine_paths(waits_for_d_full, to);
1099     struct stat stat_buf;
1100     if (lstat(dep_link_path.c_str(), &stat_buf) == -1) {
1101         if (errno != ENOENT) {
1102             cerr << "dinitctl: checking for existing dependency link: " << dep_link_path << ": "
1103                     << strerror(errno) << endl;
1104             return 1;
1105         }
1106     }
1107     else {
1108         // dependency already exists
1109         if (enable) {
1110             cerr << "dinitctl: service already enabled." << endl;
1111             return 1;
1112         }
1113     }
1114
1115     // warn if 'from' service is not started
1116     if (enable && from_state != service_state_t::STARTED) {
1117         cerr << "dinitctl: warning: enabling dependency for non-started service" << endl;
1118     }
1119
1120     // add/remove dependency
1121     constexpr int enable_pktsize = 2 + sizeof(handle_t) * 2;
1122     char cmdbuf[enable_pktsize] = { char(enable ? DINIT_CP_ENABLESERVICE : DINIT_CP_REM_DEP),
1123             char(dependency_type::WAITS_FOR)};
1124     memcpy(cmdbuf + 2, &from_handle, sizeof(from_handle));
1125     memcpy(cmdbuf + 2 + sizeof(from_handle), &to_handle, sizeof(to_handle));
1126     write_all_x(socknum, cmdbuf, enable_pktsize);
1127
1128     wait_for_reply(rbuffer, socknum);
1129
1130     // check reply
1131     if (enable && rbuffer[0] == DINIT_RP_NAK) {
1132         cerr << "dinitctl: Could not enable service: possible circular dependency" << endl;
1133         return 1;
1134     }
1135     if (rbuffer[0] != DINIT_RP_ACK) {
1136         cerr << "dinitctl: Control socket protocol error" << endl;
1137         return 1;
1138     }
1139
1140     // create link
1141     if (enable) {
1142         if (symlink((string("../") + to).c_str(), dep_link_path.c_str()) == -1) {
1143             cerr << "dinitctl: Could not create symlink at " << dep_link_path << ": " << strerror(errno)
1144                     << "\n" "dinitctl: Note: service was activated, but will not be enabled on restart."
1145                     << endl;
1146             return 1;
1147         }
1148     }
1149     else {
1150         if (unlink(dep_link_path.c_str()) == -1) {
1151             cerr << "dinitctl: Could not unlink dependency entry " << dep_link_path << ": "
1152                     << strerror(errno) << "\n"
1153                     "dinitctl: Note: service was disabled, but will be re-enabled on restart." << endl;
1154             return 1;
1155         }
1156     }
1157
1158     return 0;
1159 }