qga/main.c

   1 /*
   2  * QEMU Guest Agent
   3  *
   4  * Copyright IBM Corp. 2011
   5  *
   6  * Authors:
   7  *  Adam Litke        <aglitke@linux.vnet.ibm.com>
   8  *  Michael Roth      <mdroth@linux.vnet.ibm.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  11  * See the COPYING file in the top-level directory.
  12  */
  13
  14 #include "qemu/osdep.h"
  15 #include <getopt.h>
  16 #include <glib/gstdio.h>
  17 #ifndef _WIN32
  18 #include <syslog.h>
  19 #include <sys/wait.h>
  20 #endif
  21 #include "qapi/qmp/json-parser.h"
  22 #include "qapi/qmp/qdict.h"
  23 #include "qapi/qmp/qjson.h"
  24 #include "qapi/qmp/qstring.h"
  25 #include "guest-agent-core.h"
  26 #include "qemu/module.h"
  27 #include "qga-qapi-commands.h"
  28 #include "qapi/qmp/qerror.h"
  29 #include "qapi/error.h"
  30 #include "channel.h"
  31 #include "qemu/bswap.h"
  32 #include "qemu/help_option.h"
  33 #include "qemu/sockets.h"
  34 #include "qemu/systemd.h"
  35 #include "qemu-version.h"
  36 #ifdef _WIN32
  37 #include "qga/service-win32.h"
  38 #include "qga/vss-win32.h"
  39 #endif
  40 #ifdef __linux__
  41 #include <linux/fs.h>
  42 #ifdef FIFREEZE
  43 #define CONFIG_FSFREEZE
  44 #endif
  45 #endif
  46
  47 #ifndef _WIN32
  48 #define QGA_VIRTIO_PATH_DEFAULT "/dev/virtio-ports/org.qemu.guest_agent.0"
  49 #define QGA_STATE_RELATIVE_DIR  "run"
  50 #define QGA_SERIAL_PATH_DEFAULT "/dev/ttyS0"
  51 #else
  52 #define QGA_VIRTIO_PATH_DEFAULT "\\\\.\\Global\\org.qemu.guest_agent.0"
  53 #define QGA_STATE_RELATIVE_DIR  "qemu-ga"
  54 #define QGA_SERIAL_PATH_DEFAULT "COM1"
  55 #endif
  56 #ifdef CONFIG_FSFREEZE
  57 #define QGA_FSFREEZE_HOOK_DEFAULT CONFIG_QEMU_CONFDIR "/fsfreeze-hook"
  58 #endif
  59 #define QGA_SENTINEL_BYTE 0xFF
  60 #define QGA_CONF_DEFAULT CONFIG_QEMU_CONFDIR G_DIR_SEPARATOR_S "qemu-ga.conf"
  61 #define QGA_RETRY_INTERVAL 5
  62
  63 static struct {
  64     const char *state_dir;
  65     const char *pidfile;
  66 } dfl_pathnames;
  67
  68 typedef struct GAPersistentState {
  69 #define QGA_PSTATE_DEFAULT_FD_COUNTER 1000
  70     int64_t fd_counter;
  71 } GAPersistentState;
  72
  73 typedef struct GAConfig GAConfig;
  74
  75 struct GAState {
  76     JSONMessageParser parser;
  77     GMainLoop *main_loop;
  78     GAChannel *channel;
  79     bool virtio; /* fastpath to check for virtio to deal with poll() quirks */
  80     GACommandState *command_state;
  81     GLogLevelFlags log_level;
  82     FILE *log_file;
  83     bool logging_enabled;
  84 #ifdef _WIN32
  85     GAService service;
  86 #endif
  87     bool delimit_response;
  88     bool frozen;
  89     GList *blacklist;
  90     char *state_filepath_isfrozen;
  91     struct {
  92         const char *log_filepath;
  93         const char *pid_filepath;
  94     } deferred_options;
  95 #ifdef CONFIG_FSFREEZE
  96     const char *fsfreeze_hook;
  97 #endif
  98     gchar *pstate_filepath;
  99     GAPersistentState pstate;
 100     GAConfig *config;
 101     int socket_activation;
 102     bool force_exit;
 103 };
 104
 105 struct GAState *ga_state;
 106 QmpCommandList ga_commands;
 107
 108 /* commands that are safe to issue while filesystems are frozen */
 109 static const char *ga_freeze_whitelist[] = {
 110     "guest-ping",
 111     "guest-info",
 112     "guest-sync",
 113     "guest-sync-delimited",
 114     "guest-fsfreeze-status",
 115     "guest-fsfreeze-thaw",
 116     NULL
 117 };
 118
 119 #ifdef _WIN32
 120 DWORD WINAPI service_ctrl_handler(DWORD ctrl, DWORD type, LPVOID data,
 121                                   LPVOID ctx);
 122 VOID WINAPI service_main(DWORD argc, TCHAR *argv[]);
 123 #endif
 124 static int run_agent(GAState *s);
 125 static void stop_agent(GAState *s, bool requested);
 126
 127 static void
 128 init_dfl_pathnames(void)
 129 {
 130     g_assert(dfl_pathnames.state_dir == NULL);
 131     g_assert(dfl_pathnames.pidfile == NULL);
 132     dfl_pathnames.state_dir = qemu_get_local_state_pathname(
 133       QGA_STATE_RELATIVE_DIR);
 134     dfl_pathnames.pidfile   = qemu_get_local_state_pathname(
 135       QGA_STATE_RELATIVE_DIR G_DIR_SEPARATOR_S "qemu-ga.pid");
 136 }
 137
 138 static void quit_handler(int sig)
 139 {
 140     /* if we're frozen, don't exit unless we're absolutely forced to,
 141      * because it's basically impossible for graceful exit to complete
 142      * unless all log/pid files are on unfreezable filesystems. there's
 143      * also a very likely chance killing the agent before unfreezing
 144      * the filesystems is a mistake (or will be viewed as one later).
 145      * On Windows the freeze interval is limited to 10 seconds, so
 146      * we should quit, but first we should wait for the timeout, thaw
 147      * the filesystem and quit.
 148      */
 149     if (ga_is_frozen(ga_state)) {
 150 #ifdef _WIN32
 151         int i = 0;
 152         Error *err = NULL;
 153         HANDLE hEventTimeout;
 154
 155         g_debug("Thawing filesystems before exiting");
 156
 157         hEventTimeout = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_TIMEOUT);
 158         if (hEventTimeout) {
 159             WaitForSingleObject(hEventTimeout, 0);
 160             CloseHandle(hEventTimeout);
 161         }
 162         qga_vss_fsfreeze(&i, false, NULL, &err);
 163         if (err) {
 164             g_debug("Error unfreezing filesystems prior to exiting: %s",
 165                 error_get_pretty(err));
 166             error_free(err);
 167         }
 168 #else
 169         return;
 170 #endif
 171     }
 172     g_debug("received signal num %d, quitting", sig);
 173
 174     stop_agent(ga_state, true);
 175 }
 176
 177 #ifndef _WIN32
 178 static gboolean register_signal_handlers(void)
 179 {
 180     struct sigaction sigact;
 181     int ret;
 182
 183     memset(&sigact, 0, sizeof(struct sigaction));
 184     sigact.sa_handler = quit_handler;
 185
 186     ret = sigaction(SIGINT, &sigact, NULL);
 187     if (ret == -1) {
 188         g_error("error configuring signal handler: %s", strerror(errno));
 189     }
 190     ret = sigaction(SIGTERM, &sigact, NULL);
 191     if (ret == -1) {
 192         g_error("error configuring signal handler: %s", strerror(errno));
 193     }
 194
 195     sigact.sa_handler = SIG_IGN;
 196     if (sigaction(SIGPIPE, &sigact, NULL) != 0) {
 197         g_error("error configuring SIGPIPE signal handler: %s",
 198                 strerror(errno));
 199     }
 200
 201     return true;
 202 }
 203
 204 /* TODO: use this in place of all post-fork() fclose(std*) callers */
 205 void reopen_fd_to_null(int fd)
 206 {
 207     int nullfd;
 208
 209     nullfd = open("/dev/null", O_RDWR);
 210     if (nullfd < 0) {
 211         return;
 212     }
 213
 214     dup2(nullfd, fd);
 215
 216     if (nullfd != fd) {
 217         close(nullfd);
 218     }
 219 }
 220 #endif
 221
 222 static void usage(const char *cmd)
 223 {
 224     printf(
 225 "Usage: %s [-m <method> -p <path>] [<options>]\n"
 226 "QEMU Guest Agent " QEMU_FULL_VERSION "\n"
 227 QEMU_COPYRIGHT "\n"
 228 "\n"
 229 "  -m, --method      transport method: one of unix-listen, virtio-serial,\n"
 230 "                    isa-serial, or vsock-listen (virtio-serial is the default)\n"
 231 "  -p, --path        device/socket path (the default for virtio-serial is:\n"
 232 "                    %s,\n"
 233 "                    the default for isa-serial is:\n"
 234 "                    %s)\n"
 235 "  -l, --logfile     set logfile path, logs to stderr by default\n"
 236 "  -f, --pidfile     specify pidfile (default is %s)\n"
 237 #ifdef CONFIG_FSFREEZE
 238 "  -F, --fsfreeze-hook\n"
 239 "                    enable fsfreeze hook. Accepts an optional argument that\n"
 240 "                    specifies script to run on freeze/thaw. Script will be\n"
 241 "                    called with 'freeze'/'thaw' arguments accordingly.\n"
 242 "                    (default is %s)\n"
 243 "                    If using -F with an argument, do not follow -F with a\n"
 244 "                    space.\n"
 245 "                    (for example: -F/var/run/fsfreezehook.sh)\n"
 246 #endif
 247 "  -t, --statedir    specify dir to store state information (absolute paths\n"
 248 "                    only, default is %s)\n"
 249 "  -v, --verbose     log extra debugging information\n"
 250 "  -V, --version     print version information and exit\n"
 251 "  -d, --daemonize   become a daemon\n"
 252 #ifdef _WIN32
 253 "  -s, --service     service commands: install, uninstall, vss-install, vss-uninstall\n"
 254 #endif
 255 "  -b, --blacklist   comma-separated list of RPCs to disable (no spaces, \"?\"\n"
 256 "                    to list available RPCs)\n"
 257 "  -D, --dump-conf   dump a qemu-ga config file based on current config\n"
 258 "                    options / command-line parameters to stdout\n"
 259 "  -r, --retry-path  attempt re-opening path if it's unavailable or closed\n"
 260 "                    due to an error which may be recoverable in the future\n"
 261 "                    (virtio-serial driver re-install, serial device hot\n"
 262 "                    plug/unplug, etc.)\n"
 263 "  -h, --help        display this help and exit\n"
 264 "\n"
 265 QEMU_HELP_BOTTOM "\n"
 266     , cmd, QGA_VIRTIO_PATH_DEFAULT, QGA_SERIAL_PATH_DEFAULT,
 267     dfl_pathnames.pidfile,
 268 #ifdef CONFIG_FSFREEZE
 269     QGA_FSFREEZE_HOOK_DEFAULT,
 270 #endif
 271     dfl_pathnames.state_dir);
 272 }
 273
 274 static const char *ga_log_level_str(GLogLevelFlags level)
 275 {
 276     switch (level & G_LOG_LEVEL_MASK) {
 277         case G_LOG_LEVEL_ERROR:
 278             return "error";
 279         case G_LOG_LEVEL_CRITICAL:
 280             return "critical";
 281         case G_LOG_LEVEL_WARNING:
 282             return "warning";
 283         case G_LOG_LEVEL_MESSAGE:
 284             return "message";
 285         case G_LOG_LEVEL_INFO:
 286             return "info";
 287         case G_LOG_LEVEL_DEBUG:
 288             return "debug";
 289         default:
 290             return "user";
 291     }
 292 }
 293
 294 bool ga_logging_enabled(GAState *s)
 295 {
 296     return s->logging_enabled;
 297 }
 298
 299 void ga_disable_logging(GAState *s)
 300 {
 301     s->logging_enabled = false;
 302 }
 303
 304 void ga_enable_logging(GAState *s)
 305 {
 306     s->logging_enabled = true;
 307 }
 308
 309 static void ga_log(const gchar *domain, GLogLevelFlags level,
 310                    const gchar *msg, gpointer opaque)
 311 {
 312     GAState *s = opaque;
 313     GTimeVal time;
 314     const char *level_str = ga_log_level_str(level);
 315
 316     if (!ga_logging_enabled(s)) {
 317         return;
 318     }
 319
 320     level &= G_LOG_LEVEL_MASK;
 321 #ifndef _WIN32
 322     if (g_strcmp0(domain, "syslog") == 0) {
 323         syslog(LOG_INFO, "%s: %s", level_str, msg);
 324     } else if (level & s->log_level) {
 325 #else
 326     if (level & s->log_level) {
 327 #endif
 328         g_get_current_time(&time);
 329         fprintf(s->log_file,
 330                 "%lu.%lu: %s: %s\n", time.tv_sec, time.tv_usec, level_str, msg);
 331         fflush(s->log_file);
 332     }
 333 }
 334
 335 void ga_set_response_delimited(GAState *s)
 336 {
 337     s->delimit_response = true;
 338 }
 339
 340 static FILE *ga_open_logfile(const char *logfile)
 341 {
 342     FILE *f;
 343
 344     f = fopen(logfile, "a");
 345     if (!f) {
 346         return NULL;
 347     }
 348
 349     qemu_set_cloexec(fileno(f));
 350     return f;
 351 }
 352
 353 static gint ga_strcmp(gconstpointer str1, gconstpointer str2)
 354 {
 355     return strcmp(str1, str2);
 356 }
 357
 358 /* disable commands that aren't safe for fsfreeze */
 359 static void ga_disable_non_whitelisted(QmpCommand *cmd, void *opaque)
 360 {
 361     bool whitelisted = false;
 362     int i = 0;
 363     const char *name = qmp_command_name(cmd);
 364
 365     while (ga_freeze_whitelist[i] != NULL) {
 366         if (strcmp(name, ga_freeze_whitelist[i]) == 0) {
 367             whitelisted = true;
 368         }
 369         i++;
 370     }
 371     if (!whitelisted) {
 372         g_debug("disabling command: %s", name);
 373         qmp_disable_command(&ga_commands, name);
 374     }
 375 }
 376
 377 /* [re-]enable all commands, except those explicitly blacklisted by user */
 378 static void ga_enable_non_blacklisted(QmpCommand *cmd, void *opaque)
 379 {
 380     GList *blacklist = opaque;
 381     const char *name = qmp_command_name(cmd);
 382
 383     if (g_list_find_custom(blacklist, name, ga_strcmp) == NULL &&
 384         !qmp_command_is_enabled(cmd)) {
 385         g_debug("enabling command: %s", name);
 386         qmp_enable_command(&ga_commands, name);
 387     }
 388 }
 389
 390 static bool ga_create_file(const char *path)
 391 {
 392     int fd = open(path, O_CREAT | O_WRONLY, S_IWUSR | S_IRUSR);
 393     if (fd == -1) {
 394         g_warning("unable to open/create file %s: %s", path, strerror(errno));
 395         return false;
 396     }
 397     close(fd);
 398     return true;
 399 }
 400
 401 static bool ga_delete_file(const char *path)
 402 {
 403     int ret = unlink(path);
 404     if (ret == -1) {
 405         g_warning("unable to delete file: %s: %s", path, strerror(errno));
 406         return false;
 407     }
 408
 409     return true;
 410 }
 411
 412 bool ga_is_frozen(GAState *s)
 413 {
 414     return s->frozen;
 415 }
 416
 417 void ga_set_frozen(GAState *s)
 418 {
 419     if (ga_is_frozen(s)) {
 420         return;
 421     }
 422     /* disable all non-whitelisted (for frozen state) commands */
 423     qmp_for_each_command(&ga_commands, ga_disable_non_whitelisted, NULL);
 424     g_warning("disabling logging due to filesystem freeze");
 425     ga_disable_logging(s);
 426     s->frozen = true;
 427     if (!ga_create_file(s->state_filepath_isfrozen)) {
 428         g_warning("unable to create %s, fsfreeze may not function properly",
 429                   s->state_filepath_isfrozen);
 430     }
 431 }
 432
 433 void ga_unset_frozen(GAState *s)
 434 {
 435     if (!ga_is_frozen(s)) {
 436         return;
 437     }
 438
 439     /* if we delayed creation/opening of pid/log files due to being
 440      * in a frozen state at start up, do it now
 441      */
 442     if (s->deferred_options.log_filepath) {
 443         s->log_file = ga_open_logfile(s->deferred_options.log_filepath);
 444         if (!s->log_file) {
 445             s->log_file = stderr;
 446         }
 447         s->deferred_options.log_filepath = NULL;
 448     }
 449     ga_enable_logging(s);
 450     g_warning("logging re-enabled due to filesystem unfreeze");
 451     if (s->deferred_options.pid_filepath) {
 452         Error *err = NULL;
 453
 454         if (!qemu_write_pidfile(s->deferred_options.pid_filepath, &err)) {
 455             g_warning("%s", error_get_pretty(err));
 456             error_free(err);
 457         }
 458         s->deferred_options.pid_filepath = NULL;
 459     }
 460
 461     /* enable all disabled, non-blacklisted commands */
 462     qmp_for_each_command(&ga_commands, ga_enable_non_blacklisted, s->blacklist);
 463     s->frozen = false;
 464     if (!ga_delete_file(s->state_filepath_isfrozen)) {
 465         g_warning("unable to delete %s, fsfreeze may not function properly",
 466                   s->state_filepath_isfrozen);
 467     }
 468 }
 469
 470 #ifdef CONFIG_FSFREEZE
 471 const char *ga_fsfreeze_hook(GAState *s)
 472 {
 473     return s->fsfreeze_hook;
 474 }
 475 #endif
 476
 477 static void become_daemon(const char *pidfile)
 478 {
 479 #ifndef _WIN32
 480     pid_t pid, sid;
 481
 482     pid = fork();
 483     if (pid < 0) {
 484         exit(EXIT_FAILURE);
 485     }
 486     if (pid > 0) {
 487         exit(EXIT_SUCCESS);
 488     }
 489
 490     if (pidfile) {
 491         Error *err = NULL;
 492
 493         if (!qemu_write_pidfile(pidfile, &err)) {
 494             g_critical("%s", error_get_pretty(err));
 495             error_free(err);
 496             exit(EXIT_FAILURE);
 497         }
 498     }
 499
 500     umask(S_IRWXG | S_IRWXO);
 501     sid = setsid();
 502     if (sid < 0) {
 503         goto fail;
 504     }
 505     if ((chdir("/")) < 0) {
 506         goto fail;
 507     }
 508
 509     reopen_fd_to_null(STDIN_FILENO);
 510     reopen_fd_to_null(STDOUT_FILENO);
 511     reopen_fd_to_null(STDERR_FILENO);
 512     return;
 513
 514 fail:
 515     if (pidfile) {
 516         unlink(pidfile);
 517     }
 518     g_critical("failed to daemonize");
 519     exit(EXIT_FAILURE);
 520 #endif
 521 }
 522
 523 static int send_response(GAState *s, QDict *payload)
 524 {
 525     const char *buf;
 526     QString *payload_qstr, *response_qstr;
 527     GIOStatus status;
 528
 529     g_assert(payload && s->channel);
 530
 531     payload_qstr = qobject_to_json(QOBJECT(payload));
 532     if (!payload_qstr) {
 533         return -EINVAL;
 534     }
 535
 536     if (s->delimit_response) {
 537         s->delimit_response = false;
 538         response_qstr = qstring_new();
 539         qstring_append_chr(response_qstr, QGA_SENTINEL_BYTE);
 540         qstring_append(response_qstr, qstring_get_str(payload_qstr));
 541         qobject_unref(payload_qstr);
 542     } else {
 543         response_qstr = payload_qstr;
 544     }
 545
 546     qstring_append_chr(response_qstr, '\n');
 547     buf = qstring_get_str(response_qstr);
 548     status = ga_channel_write_all(s->channel, buf, strlen(buf));
 549     qobject_unref(response_qstr);
 550     if (status != G_IO_STATUS_NORMAL) {
 551         return -EIO;
 552     }
 553
 554     return 0;
 555 }
 556
 557 static void process_command(GAState *s, QDict *req)
 558 {
 559     QDict *rsp;
 560     int ret;
 561
 562     g_assert(req);
 563     g_debug("processing command");
 564     rsp = qmp_dispatch(&ga_commands, QOBJECT(req), false);
 565     if (rsp) {
 566         ret = send_response(s, rsp);
 567         if (ret < 0) {
 568             g_warning("error sending response: %s", strerror(-ret));
 569         }
 570         qobject_unref(rsp);
 571     }
 572 }
 573
 574 /* handle requests/control events coming in over the channel */
 575 static void process_event(void *opaque, QObject *obj, Error *err)
 576 {
 577     GAState *s = opaque;
 578     QDict *req, *rsp;
 579     int ret;
 580
 581     g_debug("process_event: called");
 582     assert(!obj != !err);
 583     if (err) {
 584         goto err;
 585     }
 586     req = qobject_to(QDict, obj);
 587     if (!req) {
 588         error_setg(&err, "Input must be a JSON object");
 589         goto err;
 590     }
 591     if (!qdict_haskey(req, "execute")) {
 592         g_warning("unrecognized payload format");
 593         error_setg(&err, QERR_UNSUPPORTED);
 594         goto err;
 595     }
 596
 597     process_command(s, req);
 598     qobject_unref(obj);
 599     return;
 600
 601 err:
 602     g_warning("failed to parse event: %s", error_get_pretty(err));
 603     rsp = qmp_error_response(err);
 604     ret = send_response(s, rsp);
 605     if (ret < 0) {
 606         g_warning("error sending error response: %s", strerror(-ret));
 607     }
 608     qobject_unref(rsp);
 609     qobject_unref(obj);
 610 }
 611
 612 /* false return signals GAChannel to close the current client connection */
 613 static gboolean channel_event_cb(GIOCondition condition, gpointer data)
 614 {
 615     GAState *s = data;
 616     gchar buf[QGA_READ_COUNT_DEFAULT+1];
 617     gsize count;
 618     GIOStatus status = ga_channel_read(s->channel, buf, QGA_READ_COUNT_DEFAULT, &count);
 619     switch (status) {
 620     case G_IO_STATUS_ERROR:
 621         g_warning("error reading channel");
 622         stop_agent(s, false);
 623         return false;
 624     case G_IO_STATUS_NORMAL:
 625         buf[count] = 0;
 626         g_debug("read data, count: %d, data: %s", (int)count, buf);
 627         json_message_parser_feed(&s->parser, (char *)buf, (int)count);
 628         break;
 629     case G_IO_STATUS_EOF:
 630         g_debug("received EOF");
 631         if (!s->virtio) {
 632             return false;
 633         }
 634         /* fall through */
 635     case G_IO_STATUS_AGAIN:
 636         /* virtio causes us to spin here when no process is attached to
 637          * host-side chardev. sleep a bit to mitigate this
 638          */
 639         if (s->virtio) {
 640             usleep(100*1000);
 641         }
 642         return true;
 643     default:
 644         g_warning("unknown channel read status, closing");
 645         return false;
 646     }
 647     return true;
 648 }
 649
 650 static gboolean channel_init(GAState *s, const gchar *method, const gchar *path,
 651                              int listen_fd)
 652 {
 653     GAChannelMethod channel_method;
 654
 655     if (strcmp(method, "virtio-serial") == 0) {
 656         s->virtio = true; /* virtio requires special handling in some cases */
 657         channel_method = GA_CHANNEL_VIRTIO_SERIAL;
 658     } else if (strcmp(method, "isa-serial") == 0) {
 659         channel_method = GA_CHANNEL_ISA_SERIAL;
 660     } else if (strcmp(method, "unix-listen") == 0) {
 661         channel_method = GA_CHANNEL_UNIX_LISTEN;
 662     } else if (strcmp(method, "vsock-listen") == 0) {
 663         channel_method = GA_CHANNEL_VSOCK_LISTEN;
 664     } else {
 665         g_critical("unsupported channel method/type: %s", method);
 666         return false;
 667     }
 668
 669     s->channel = ga_channel_new(channel_method, path, listen_fd,
 670                                 channel_event_cb, s);
 671     if (!s->channel) {
 672         g_critical("failed to create guest agent channel");
 673         return false;
 674     }
 675
 676     return true;
 677 }
 678
 679 #ifdef _WIN32
 680 DWORD WINAPI service_ctrl_handler(DWORD ctrl, DWORD type, LPVOID data,
 681                                   LPVOID ctx)
 682 {
 683     DWORD ret = NO_ERROR;
 684     GAService *service = &ga_state->service;
 685
 686     switch (ctrl)
 687     {
 688         case SERVICE_CONTROL_STOP:
 689         case SERVICE_CONTROL_SHUTDOWN:
 690             quit_handler(SIGTERM);
 691             service->status.dwCurrentState = SERVICE_STOP_PENDING;
 692             SetServiceStatus(service->status_handle, &service->status);
 693             break;
 694
 695         default:
 696             ret = ERROR_CALL_NOT_IMPLEMENTED;
 697     }
 698     return ret;
 699 }
 700
 701 VOID WINAPI service_main(DWORD argc, TCHAR *argv[])
 702 {
 703     GAService *service = &ga_state->service;
 704
 705     service->status_handle = RegisterServiceCtrlHandlerEx(QGA_SERVICE_NAME,
 706         service_ctrl_handler, NULL);
 707
 708     if (service->status_handle == 0) {
 709         g_critical("Failed to register extended requests function!\n");
 710         return;
 711     }
 712
 713     service->status.dwServiceType = SERVICE_WIN32;
 714     service->status.dwCurrentState = SERVICE_RUNNING;
 715     service->status.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 716     service->status.dwWin32ExitCode = NO_ERROR;
 717     service->status.dwServiceSpecificExitCode = NO_ERROR;
 718     service->status.dwCheckPoint = 0;
 719     service->status.dwWaitHint = 0;
 720     SetServiceStatus(service->status_handle, &service->status);
 721
 722     run_agent(ga_state);
 723
 724     service->status.dwCurrentState = SERVICE_STOPPED;
 725     SetServiceStatus(service->status_handle, &service->status);
 726 }
 727 #endif
 728
 729 static void set_persistent_state_defaults(GAPersistentState *pstate)
 730 {
 731     g_assert(pstate);
 732     pstate->fd_counter = QGA_PSTATE_DEFAULT_FD_COUNTER;
 733 }
 734
 735 static void persistent_state_from_keyfile(GAPersistentState *pstate,
 736                                           GKeyFile *keyfile)
 737 {
 738     g_assert(pstate);
 739     g_assert(keyfile);
 740     /* if any fields are missing, either because the file was tampered with
 741      * by agents of chaos, or because the field wasn't present at the time the
 742      * file was created, the best we can ever do is start over with the default
 743      * values. so load them now, and ignore any errors in accessing key-value
 744      * pairs
 745      */
 746     set_persistent_state_defaults(pstate);
 747
 748     if (g_key_file_has_key(keyfile, "global", "fd_counter", NULL)) {
 749         pstate->fd_counter =
 750             g_key_file_get_integer(keyfile, "global", "fd_counter", NULL);
 751     }
 752 }
 753
 754 static void persistent_state_to_keyfile(const GAPersistentState *pstate,
 755                                         GKeyFile *keyfile)
 756 {
 757     g_assert(pstate);
 758     g_assert(keyfile);
 759
 760     g_key_file_set_integer(keyfile, "global", "fd_counter", pstate->fd_counter);
 761 }
 762
 763 static gboolean write_persistent_state(const GAPersistentState *pstate,
 764                                        const gchar *path)
 765 {
 766     GKeyFile *keyfile = g_key_file_new();
 767     GError *gerr = NULL;
 768     gboolean ret = true;
 769     gchar *data = NULL;
 770     gsize data_len;
 771
 772     g_assert(pstate);
 773
 774     persistent_state_to_keyfile(pstate, keyfile);
 775     data = g_key_file_to_data(keyfile, &data_len, &gerr);
 776     if (gerr) {
 777         g_critical("failed to convert persistent state to string: %s",
 778                    gerr->message);
 779         ret = false;
 780         goto out;
 781     }
 782
 783     g_file_set_contents(path, data, data_len, &gerr);
 784     if (gerr) {
 785         g_critical("failed to write persistent state to %s: %s",
 786                     path, gerr->message);
 787         ret = false;
 788         goto out;
 789     }
 790
 791 out:
 792     if (gerr) {
 793         g_error_free(gerr);
 794     }
 795     if (keyfile) {
 796         g_key_file_free(keyfile);
 797     }
 798     g_free(data);
 799     return ret;
 800 }
 801
 802 static gboolean read_persistent_state(GAPersistentState *pstate,
 803                                       const gchar *path, gboolean frozen)
 804 {
 805     GKeyFile *keyfile = NULL;
 806     GError *gerr = NULL;
 807     struct stat st;
 808     gboolean ret = true;
 809
 810     g_assert(pstate);
 811
 812     if (stat(path, &st) == -1) {
 813         /* it's okay if state file doesn't exist, but any other error
 814          * indicates a permissions issue or some other misconfiguration
 815          * that we likely won't be able to recover from.
 816          */
 817         if (errno != ENOENT) {
 818             g_critical("unable to access state file at path %s: %s",
 819                        path, strerror(errno));
 820             ret = false;
 821             goto out;
 822         }
 823
 824         /* file doesn't exist. initialize state to default values and
 825          * attempt to save now. (we could wait till later when we have
 826          * modified state we need to commit, but if there's a problem,
 827          * such as a missing parent directory, we want to catch it now)
 828          *
 829          * there is a potential scenario where someone either managed to
 830          * update the agent from a version that didn't use a key store
 831          * while qemu-ga thought the filesystem was frozen, or
 832          * deleted the key store prior to issuing a fsfreeze, prior
 833          * to restarting the agent. in this case we go ahead and defer
 834          * initial creation till we actually have modified state to
 835          * write, otherwise fail to recover from freeze.
 836          */
 837         set_persistent_state_defaults(pstate);
 838         if (!frozen) {
 839             ret = write_persistent_state(pstate, path);
 840             if (!ret) {
 841                 g_critical("unable to create state file at path %s", path);
 842                 ret = false;
 843                 goto out;
 844             }
 845         }
 846         ret = true;
 847         goto out;
 848     }
 849
 850     keyfile = g_key_file_new();
 851     g_key_file_load_from_file(keyfile, path, 0, &gerr);
 852     if (gerr) {
 853         g_critical("error loading persistent state from path: %s, %s",
 854                    path, gerr->message);
 855         ret = false;
 856         goto out;
 857     }
 858
 859     persistent_state_from_keyfile(pstate, keyfile);
 860
 861 out:
 862     if (keyfile) {
 863         g_key_file_free(keyfile);
 864     }
 865     if (gerr) {
 866         g_error_free(gerr);
 867     }
 868
 869     return ret;
 870 }
 871
 872 int64_t ga_get_fd_handle(GAState *s, Error **errp)
 873 {
 874     int64_t handle;
 875
 876     g_assert(s->pstate_filepath);
 877     /* we blacklist commands and avoid operations that potentially require
 878      * writing to disk when we're in a frozen state. this includes opening
 879      * new files, so we should never get here in that situation
 880      */
 881     g_assert(!ga_is_frozen(s));
 882
 883     handle = s->pstate.fd_counter++;
 884
 885     /* This should never happen on a reasonable timeframe, as guest-file-open
 886      * would have to be issued 2^63 times */
 887     if (s->pstate.fd_counter == INT64_MAX) {
 888         abort();
 889     }
 890
 891     if (!write_persistent_state(&s->pstate, s->pstate_filepath)) {
 892         error_setg(errp, "failed to commit persistent state to disk");
 893         return -1;
 894     }
 895
 896     return handle;
 897 }
 898
 899 static void ga_print_cmd(QmpCommand *cmd, void *opaque)
 900 {
 901     printf("%s\n", qmp_command_name(cmd));
 902 }
 903
 904 static GList *split_list(const gchar *str, const gchar *delim)
 905 {
 906     GList *list = NULL;
 907     int i;
 908     gchar **strv;
 909
 910     strv = g_strsplit(str, delim, -1);
 911     for (i = 0; strv[i]; i++) {
 912         list = g_list_prepend(list, strv[i]);
 913     }
 914     g_free(strv);
 915
 916     return list;
 917 }
 918
 919 struct GAConfig {
 920     char *channel_path;
 921     char *method;
 922     char *log_filepath;
 923     char *pid_filepath;
 924 #ifdef CONFIG_FSFREEZE
 925     char *fsfreeze_hook;
 926 #endif
 927     char *state_dir;
 928 #ifdef _WIN32
 929     const char *service;
 930 #endif
 931     gchar *bliststr; /* blacklist may point to this string */
 932     GList *blacklist;
 933     int daemonize;
 934     GLogLevelFlags log_level;
 935     int dumpconf;
 936     bool retry_path;
 937 };
 938
 939 static void config_load(GAConfig *config)
 940 {
 941     GError *gerr = NULL;
 942     GKeyFile *keyfile;
 943     const char *conf = g_getenv("QGA_CONF") ?: QGA_CONF_DEFAULT;
 944
 945     /* read system config */
 946     keyfile = g_key_file_new();
 947     if (!g_key_file_load_from_file(keyfile, conf, 0, &gerr)) {
 948         goto end;
 949     }
 950     if (g_key_file_has_key(keyfile, "general", "daemon", NULL)) {
 951         config->daemonize =
 952             g_key_file_get_boolean(keyfile, "general", "daemon", &gerr);
 953     }
 954     if (g_key_file_has_key(keyfile, "general", "method", NULL)) {
 955         config->method =
 956             g_key_file_get_string(keyfile, "general", "method", &gerr);
 957     }
 958     if (g_key_file_has_key(keyfile, "general", "path", NULL)) {
 959         config->channel_path =
 960             g_key_file_get_string(keyfile, "general", "path", &gerr);
 961     }
 962     if (g_key_file_has_key(keyfile, "general", "logfile", NULL)) {
 963         config->log_filepath =
 964             g_key_file_get_string(keyfile, "general", "logfile", &gerr);
 965     }
 966     if (g_key_file_has_key(keyfile, "general", "pidfile", NULL)) {
 967         config->pid_filepath =
 968             g_key_file_get_string(keyfile, "general", "pidfile", &gerr);
 969     }
 970 #ifdef CONFIG_FSFREEZE
 971     if (g_key_file_has_key(keyfile, "general", "fsfreeze-hook", NULL)) {
 972         config->fsfreeze_hook =
 973             g_key_file_get_string(keyfile,
 974                                   "general", "fsfreeze-hook", &gerr);
 975     }
 976 #endif
 977     if (g_key_file_has_key(keyfile, "general", "statedir", NULL)) {
 978         config->state_dir =
 979             g_key_file_get_string(keyfile, "general", "statedir", &gerr);
 980     }
 981     if (g_key_file_has_key(keyfile, "general", "verbose", NULL) &&
 982         g_key_file_get_boolean(keyfile, "general", "verbose", &gerr)) {
 983         /* enable all log levels */
 984         config->log_level = G_LOG_LEVEL_MASK;
 985     }
 986     if (g_key_file_has_key(keyfile, "general", "retry-path", NULL)) {
 987         config->retry_path =
 988             g_key_file_get_boolean(keyfile, "general", "retry-path", &gerr);
 989     }
 990     if (g_key_file_has_key(keyfile, "general", "blacklist", NULL)) {
 991         config->bliststr =
 992             g_key_file_get_string(keyfile, "general", "blacklist", &gerr);
 993         config->blacklist = g_list_concat(config->blacklist,
 994                                           split_list(config->bliststr, ","));
 995     }
 996
 997 end:
 998     g_key_file_free(keyfile);
 999     if (gerr &&
1000         !(gerr->domain == G_FILE_ERROR && gerr->code == G_FILE_ERROR_NOENT)) {
1001         g_critical("error loading configuration from path: %s, %s",
1002                    QGA_CONF_DEFAULT, gerr->message);
1003         exit(EXIT_FAILURE);
1004     }
1005     g_clear_error(&gerr);
1006 }
1007
1008 static gchar *list_join(GList *list, const gchar separator)
1009 {
1010     GString *str = g_string_new("");
1011
1012     while (list) {
1013         str = g_string_append(str, (gchar *)list->data);
1014         list = g_list_next(list);
1015         if (list) {
1016             str = g_string_append_c(str, separator);
1017         }
1018     }
1019
1020     return g_string_free(str, FALSE);
1021 }
1022
1023 static void config_dump(GAConfig *config)
1024 {
1025     GError *error = NULL;
1026     GKeyFile *keyfile;
1027     gchar *tmp;
1028
1029     keyfile = g_key_file_new();
1030     g_assert(keyfile);
1031
1032     g_key_file_set_boolean(keyfile, "general", "daemon", config->daemonize);
1033     g_key_file_set_string(keyfile, "general", "method", config->method);
1034     if (config->channel_path) {
1035         g_key_file_set_string(keyfile, "general", "path", config->channel_path);
1036     }
1037     if (config->log_filepath) {
1038         g_key_file_set_string(keyfile, "general", "logfile",
1039                               config->log_filepath);
1040     }
1041     g_key_file_set_string(keyfile, "general", "pidfile", config->pid_filepath);
1042 #ifdef CONFIG_FSFREEZE
1043     if (config->fsfreeze_hook) {
1044         g_key_file_set_string(keyfile, "general", "fsfreeze-hook",
1045                               config->fsfreeze_hook);
1046     }
1047 #endif
1048     g_key_file_set_string(keyfile, "general", "statedir", config->state_dir);
1049     g_key_file_set_boolean(keyfile, "general", "verbose",
1050                            config->log_level == G_LOG_LEVEL_MASK);
1051     g_key_file_set_boolean(keyfile, "general", "retry-path",
1052                            config->retry_path);
1053     tmp = list_join(config->blacklist, ',');
1054     g_key_file_set_string(keyfile, "general", "blacklist", tmp);
1055     g_free(tmp);
1056
1057     tmp = g_key_file_to_data(keyfile, NULL, &error);
1058     if (error) {
1059         g_critical("Failed to dump keyfile: %s", error->message);
1060         g_clear_error(&error);
1061     } else {
1062         printf("%s", tmp);
1063     }
1064
1065     g_free(tmp);
1066     g_key_file_free(keyfile);
1067 }
1068
1069 static void config_parse(GAConfig *config, int argc, char **argv)
1070 {
1071     const char *sopt = "hVvdm:p:l:f:F::b:s:t:Dr";
1072     int opt_ind = 0, ch;
1073     const struct option lopt[] = {
1074         { "help", 0, NULL, 'h' },
1075         { "version", 0, NULL, 'V' },
1076         { "dump-conf", 0, NULL, 'D' },
1077         { "logfile", 1, NULL, 'l' },
1078         { "pidfile", 1, NULL, 'f' },
1079 #ifdef CONFIG_FSFREEZE
1080         { "fsfreeze-hook", 2, NULL, 'F' },
1081 #endif
1082         { "verbose", 0, NULL, 'v' },
1083         { "method", 1, NULL, 'm' },
1084         { "path", 1, NULL, 'p' },
1085         { "daemonize", 0, NULL, 'd' },
1086         { "blacklist", 1, NULL, 'b' },
1087 #ifdef _WIN32
1088         { "service", 1, NULL, 's' },
1089 #endif
1090         { "statedir", 1, NULL, 't' },
1091         { "retry-path", 0, NULL, 'r' },
1092         { NULL, 0, NULL, 0 }
1093     };
1094
1095     while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
1096         switch (ch) {
1097         case 'm':
1098             g_free(config->method);
1099             config->method = g_strdup(optarg);
1100             break;
1101         case 'p':
1102             g_free(config->channel_path);
1103             config->channel_path = g_strdup(optarg);
1104             break;
1105         case 'l':
1106             g_free(config->log_filepath);
1107             config->log_filepath = g_strdup(optarg);
1108             break;
1109         case 'f':
1110             g_free(config->pid_filepath);
1111             config->pid_filepath = g_strdup(optarg);
1112             break;
1113 #ifdef CONFIG_FSFREEZE
1114         case 'F':
1115             g_free(config->fsfreeze_hook);
1116             config->fsfreeze_hook = g_strdup(optarg ?: QGA_FSFREEZE_HOOK_DEFAULT);
1117             break;
1118 #endif
1119         case 't':
1120             g_free(config->state_dir);
1121             config->state_dir = g_strdup(optarg);
1122             break;
1123         case 'v':
1124             /* enable all log levels */
1125             config->log_level = G_LOG_LEVEL_MASK;
1126             break;
1127         case 'V':
1128             printf("QEMU Guest Agent %s\n", QEMU_VERSION);
1129             exit(EXIT_SUCCESS);
1130         case 'd':
1131             config->daemonize = 1;
1132             break;
1133         case 'D':
1134             config->dumpconf = 1;
1135             break;
1136         case 'r':
1137             config->retry_path = true;
1138             break;
1139         case 'b': {
1140             if (is_help_option(optarg)) {
1141                 qmp_for_each_command(&ga_commands, ga_print_cmd, NULL);
1142                 exit(EXIT_SUCCESS);
1143             }
1144             config->blacklist = g_list_concat(config->blacklist,
1145                                              split_list(optarg, ","));
1146             break;
1147         }
1148 #ifdef _WIN32
1149         case 's':
1150             config->service = optarg;
1151             if (strcmp(config->service, "install") == 0) {
1152                 if (ga_install_vss_provider()) {
1153                     exit(EXIT_FAILURE);
1154                 }
1155                 if (ga_install_service(config->channel_path,
1156                                        config->log_filepath, config->state_dir)) {
1157                     exit(EXIT_FAILURE);
1158                 }
1159                 exit(EXIT_SUCCESS);
1160             } else if (strcmp(config->service, "uninstall") == 0) {
1161                 ga_uninstall_vss_provider();
1162                 exit(ga_uninstall_service());
1163             } else if (strcmp(config->service, "vss-install") == 0) {
1164                 if (ga_install_vss_provider()) {
1165                     exit(EXIT_FAILURE);
1166                 }
1167                 exit(EXIT_SUCCESS);
1168             } else if (strcmp(config->service, "vss-uninstall") == 0) {
1169                 ga_uninstall_vss_provider();
1170                 exit(EXIT_SUCCESS);
1171             } else {
1172                 printf("Unknown service command.\n");
1173                 exit(EXIT_FAILURE);
1174             }
1175             break;
1176 #endif
1177         case 'h':
1178             usage(argv[0]);
1179             exit(EXIT_SUCCESS);
1180         case '?':
1181             g_print("Unknown option, try '%s --help' for more information.\n",
1182                     argv[0]);
1183             exit(EXIT_FAILURE);
1184         }
1185     }
1186 }
1187
1188 static void config_free(GAConfig *config)
1189 {
1190     g_free(config->method);
1191     g_free(config->log_filepath);
1192     g_free(config->pid_filepath);
1193     g_free(config->state_dir);
1194     g_free(config->channel_path);
1195     g_free(config->bliststr);
1196 #ifdef CONFIG_FSFREEZE
1197     g_free(config->fsfreeze_hook);
1198 #endif
1199     g_list_free_full(config->blacklist, g_free);
1200     g_free(config);
1201 }
1202
1203 static bool check_is_frozen(GAState *s)
1204 {
1205 #ifndef _WIN32
1206     /* check if a previous instance of qemu-ga exited with filesystems' state
1207      * marked as frozen. this could be a stale value (a non-qemu-ga process
1208      * or reboot may have since unfrozen them), but better to require an
1209      * uneeded unfreeze than to risk hanging on start-up
1210      */
1211     struct stat st;
1212     if (stat(s->state_filepath_isfrozen, &st) == -1) {
1213         /* it's okay if the file doesn't exist, but if we can't access for
1214          * some other reason, such as permissions, there's a configuration
1215          * that needs to be addressed. so just bail now before we get into
1216          * more trouble later
1217          */
1218         if (errno != ENOENT) {
1219             g_critical("unable to access state file at path %s: %s",
1220                        s->state_filepath_isfrozen, strerror(errno));
1221             return EXIT_FAILURE;
1222         }
1223     } else {
1224         g_warning("previous instance appears to have exited with frozen"
1225                   " filesystems. deferring logging/pidfile creation and"
1226                   " disabling non-fsfreeze-safe commands until"
1227                   " guest-fsfreeze-thaw is issued, or filesystems are"
1228                   " manually unfrozen and the file %s is removed",
1229                   s->state_filepath_isfrozen);
1230         return true;
1231     }
1232 #endif
1233     return false;
1234 }
1235
1236 static GAState *initialize_agent(GAConfig *config, int socket_activation)
1237 {
1238     GAState *s = g_new0(GAState, 1);
1239
1240     g_assert(ga_state == NULL);
1241
1242     s->log_level = config->log_level;
1243     s->log_file = stderr;
1244 #ifdef CONFIG_FSFREEZE
1245     s->fsfreeze_hook = config->fsfreeze_hook;
1246 #endif
1247     s->pstate_filepath = g_strdup_printf("%s/qga.state", config->state_dir);
1248     s->state_filepath_isfrozen = g_strdup_printf("%s/qga.state.isfrozen",
1249                                                  config->state_dir);
1250     s->frozen = check_is_frozen(s);
1251
1252     g_log_set_default_handler(ga_log, s);
1253     g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR);
1254     ga_enable_logging(s);
1255
1256 #ifdef _WIN32
1257     /* On win32 the state directory is application specific (be it the default
1258      * or a user override). We got past the command line parsing; let's create
1259      * the directory (with any intermediate directories). If we run into an
1260      * error later on, we won't try to clean up the directory, it is considered
1261      * persistent.
1262      */
1263     if (g_mkdir_with_parents(config->state_dir, S_IRWXU) == -1) {
1264         g_critical("unable to create (an ancestor of) the state directory"
1265                    " '%s': %s", config->state_dir, strerror(errno));
1266         return NULL;
1267     }
1268 #endif
1269
1270     if (ga_is_frozen(s)) {
1271         if (config->daemonize) {
1272             /* delay opening/locking of pidfile till filesystems are unfrozen */
1273             s->deferred_options.pid_filepath = config->pid_filepath;
1274             become_daemon(NULL);
1275         }
1276         if (config->log_filepath) {
1277             /* delay opening the log file till filesystems are unfrozen */
1278             s->deferred_options.log_filepath = config->log_filepath;
1279         }
1280         ga_disable_logging(s);
1281         qmp_for_each_command(&ga_commands, ga_disable_non_whitelisted, NULL);
1282     } else {
1283         if (config->daemonize) {
1284             become_daemon(config->pid_filepath);
1285         }
1286         if (config->log_filepath) {
1287             FILE *log_file = ga_open_logfile(config->log_filepath);
1288             if (!log_file) {
1289                 g_critical("unable to open specified log file: %s",
1290                            strerror(errno));
1291                 return NULL;
1292             }
1293             s->log_file = log_file;
1294         }
1295     }
1296
1297     /* load persistent state from disk */
1298     if (!read_persistent_state(&s->pstate,
1299                                s->pstate_filepath,
1300                                ga_is_frozen(s))) {
1301         g_critical("failed to load persistent state");
1302         return NULL;
1303     }
1304
1305     config->blacklist = ga_command_blacklist_init(config->blacklist);
1306     if (config->blacklist) {
1307         GList *l = config->blacklist;
1308         s->blacklist = config->blacklist;
1309         do {
1310             g_debug("disabling command: %s", (char *)l->data);
1311             qmp_disable_command(&ga_commands, l->data);
1312             l = g_list_next(l);
1313         } while (l);
1314     }
1315     s->command_state = ga_command_state_new();
1316     ga_command_state_init(s, s->command_state);
1317     ga_command_state_init_all(s->command_state);
1318     json_message_parser_init(&s->parser, process_event, s, NULL);
1319
1320 #ifndef _WIN32
1321     if (!register_signal_handlers()) {
1322         g_critical("failed to register signal handlers");
1323         return NULL;
1324     }
1325 #endif
1326
1327     s->main_loop = g_main_loop_new(NULL, false);
1328
1329     s->config = config;
1330     s->socket_activation = socket_activation;
1331     ga_state = s;
1332     return s;
1333 }
1334
1335 static void cleanup_agent(GAState *s)
1336 {
1337     if (s->command_state) {
1338         ga_command_state_cleanup_all(s->command_state);
1339         ga_command_state_free(s->command_state);
1340         json_message_parser_destroy(&s->parser);
1341     }
1342     g_free(s->pstate_filepath);
1343     g_free(s->state_filepath_isfrozen);
1344     if (s->main_loop) {
1345         g_main_loop_unref(s->main_loop);
1346     }
1347     g_free(s);
1348     ga_state = NULL;
1349 }
1350
1351 static int run_agent_once(GAState *s)
1352 {
1353     if (!channel_init(s, s->config->method, s->config->channel_path,
1354                       s->socket_activation ? FIRST_SOCKET_ACTIVATION_FD : -1)) {
1355         g_critical("failed to initialize guest agent channel");
1356         return EXIT_FAILURE;
1357     }
1358
1359     g_main_loop_run(ga_state->main_loop);
1360
1361     if (s->channel) {
1362         ga_channel_free(s->channel);
1363     }
1364
1365     return EXIT_SUCCESS;
1366 }
1367
1368 static int run_agent(GAState *s)
1369 {
1370     int ret = EXIT_SUCCESS;
1371
1372     s->force_exit = false;
1373
1374     do {
1375         ret = run_agent_once(s);
1376         if (s->config->retry_path && !s->force_exit) {
1377             g_warning("agent stopped unexpectedly, restarting...");
1378             sleep(QGA_RETRY_INTERVAL);
1379         }
1380     } while (s->config->retry_path && !s->force_exit);
1381
1382     return ret;
1383 }
1384
1385 static void stop_agent(GAState *s, bool requested)
1386 {
1387     if (!s->force_exit) {
1388         s->force_exit = requested;
1389     }
1390
1391     if (g_main_loop_is_running(s->main_loop)) {
1392         g_main_loop_quit(s->main_loop);
1393     }
1394 }
1395
1396 int main(int argc, char **argv)
1397 {
1398     int ret = EXIT_SUCCESS;
1399     GAState *s;
1400     GAConfig *config = g_new0(GAConfig, 1);
1401     int socket_activation;
1402
1403     config->log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL;
1404
1405     qga_qmp_init_marshal(&ga_commands);
1406
1407     init_dfl_pathnames();
1408     config_load(config);
1409     config_parse(config, argc, argv);
1410
1411     if (config->pid_filepath == NULL) {
1412         config->pid_filepath = g_strdup(dfl_pathnames.pidfile);
1413     }
1414
1415     if (config->state_dir == NULL) {
1416         config->state_dir = g_strdup(dfl_pathnames.state_dir);
1417     }
1418
1419     if (config->method == NULL) {
1420         config->method = g_strdup("virtio-serial");
1421     }
1422
1423     socket_activation = check_socket_activation();
1424     if (socket_activation > 1) {
1425         g_critical("qemu-ga only supports listening on one socket");
1426         ret = EXIT_FAILURE;
1427         goto end;
1428     }
1429     if (socket_activation) {
1430         SocketAddress *addr;
1431
1432         g_free(config->method);
1433         g_free(config->channel_path);
1434         config->method = NULL;
1435         config->channel_path = NULL;
1436
1437         addr = socket_local_address(FIRST_SOCKET_ACTIVATION_FD, NULL);
1438         if (addr) {
1439             if (addr->type == SOCKET_ADDRESS_TYPE_UNIX) {
1440                 config->method = g_strdup("unix-listen");
1441             } else if (addr->type == SOCKET_ADDRESS_TYPE_VSOCK) {
1442                 config->method = g_strdup("vsock-listen");
1443             }
1444
1445             qapi_free_SocketAddress(addr);
1446         }
1447
1448         if (!config->method) {
1449             g_critical("unsupported listen fd type");
1450             ret = EXIT_FAILURE;
1451             goto end;
1452         }
1453     } else if (config->channel_path == NULL) {
1454         if (strcmp(config->method, "virtio-serial") == 0) {
1455             /* try the default path for the virtio-serial port */
1456             config->channel_path = g_strdup(QGA_VIRTIO_PATH_DEFAULT);
1457         } else if (strcmp(config->method, "isa-serial") == 0) {
1458             /* try the default path for the serial port - COM1 */
1459             config->channel_path = g_strdup(QGA_SERIAL_PATH_DEFAULT);
1460         } else {
1461             g_critical("must specify a path for this channel");
1462             ret = EXIT_FAILURE;
1463             goto end;
1464         }
1465     }
1466
1467     if (config->dumpconf) {
1468         config_dump(config);
1469         goto end;
1470     }
1471
1472     s = initialize_agent(config, socket_activation);
1473     if (!s) {
1474         g_critical("error initializing guest agent");
1475         goto end;
1476     }
1477
1478 #ifdef _WIN32
1479     if (config->daemonize) {
1480         SERVICE_TABLE_ENTRY service_table[] = {
1481             { (char *)QGA_SERVICE_NAME, service_main }, { NULL, NULL } };
1482         StartServiceCtrlDispatcher(service_table);
1483     } else {
1484         ret = run_agent(s);
1485     }
1486 #else
1487     ret = run_agent(s);
1488 #endif
1489
1490     cleanup_agent(s);
1491
1492 end:
1493     if (config->daemonize) {
1494         unlink(config->pid_filepath);
1495     }
1496
1497     config_free(config);
1498
1499     return ret;
1500 }