path: root/src/daemon/main.c

/***
  This file is part of PulseAudio.

  Copyright 2004-2006 Lennart Poettering
  Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB

  PulseAudio is free software; you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as published
  by the Free Software Foundation; either version 2.1 of the License,
  or (at your option) any later version.

  PulseAudio is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with PulseAudio; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  USA.
***/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <signal.h>
#include <stddef.h>
#include <ltdl.h>
#include <limits.h>
#include <unistd.h>
#include <locale.h>
#include <sys/types.h>
#include <sys/stat.h>

#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif

#ifdef HAVE_PWD_H
#include <pwd.h>
#endif
#ifdef HAVE_GRP_H
#include <grp.h>
#endif

#ifdef HAVE_LIBWRAP
#include <syslog.h>
#include <tcpd.h>
#endif

#ifdef HAVE_DBUS
#include <dbus/dbus.h>
#endif

#include <pulse/client-conf.h>
#ifdef HAVE_X11
#include <pulse/client-conf-x11.h>
#endif
#include <pulse/mainloop.h>
#include <pulse/mainloop-signal.h>
#include <pulse/timeval.h>
#include <pulse/xmalloc.h>

#include <pulsecore/i18n.h>
#include <pulsecore/lock-autospawn.h>
#include <pulsecore/socket.h>
#include <pulsecore/core-error.h>
#include <pulsecore/core-rtclock.h>
#include <pulsecore/core-scache.h>
#include <pulsecore/core.h>
#include <pulsecore/module.h>
#include <pulsecore/cli-command.h>
#include <pulsecore/log.h>
#include <pulsecore/core-util.h>
#include <pulsecore/sioman.h>
#include <pulsecore/cli-text.h>
#include <pulsecore/pid.h>
#include <pulsecore/random.h>
#include <pulsecore/macro.h>
#include <pulsecore/shm.h>
#include <pulsecore/memtrap.h>
#include <pulsecore/strlist.h>
#ifdef HAVE_DBUS
#include <pulsecore/dbus-shared.h>
#endif
#include <pulsecore/cpu-arm.h>
#include <pulsecore/cpu-x86.h>
#include <pulsecore/cpu-orc.h>

#include "cmdline.h"
#include "cpulimit.h"
#include "daemon-conf.h"
#include "dumpmodules.h"
#include "caps.h"
#include "ltdl-bind-now.h"
#include "server-lookup.h"

#ifdef HAVE_LIBWRAP
/* Only one instance of these variables */
int allow_severity = LOG_INFO;
int deny_severity = LOG_WARNING;
#endif

#ifdef HAVE_OSS_WRAPPER
/* padsp looks for this symbol in the running process and disables
 * itself if it finds it and it is set to 7 (which is actually a bit
 * mask). For details see padsp. */
int __padsp_disabled__ = 7;
#endif

#ifdef OS_IS_WIN32

static void message_cb(pa_mainloop_api*a, pa_time_event*e, const struct timeval *tv, void *userdata) {
    MSG msg;
    struct timeval tvnext;

    while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
        if (msg.message == WM_QUIT)
            raise(SIGTERM);
        else {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
    }

    pa_timeval_add(pa_gettimeofday(&tvnext), 100000);
    a->time_restart(e, &tvnext);
}

#endif

static void signal_callback(pa_mainloop_api*m, pa_signal_event *e, int sig, void *userdata) {
    pa_log_info(_("Got signal %s."), pa_sig2str(sig));

    switch (sig) {
#ifdef SIGUSR1
        case SIGUSR1:
            pa_module_load(userdata, "module-cli", NULL);
            break;
#endif

#ifdef SIGUSR2
        case SIGUSR2:
            pa_module_load(userdata, "module-cli-protocol-unix", NULL);
            break;
#endif

#ifdef SIGHUP
        case SIGHUP: {
            char *c = pa_full_status_string(userdata);
            pa_log_notice("%s", c);
            pa_xfree(c);
            return;
        }
#endif

        case SIGINT:
        case SIGTERM:
        default:
            pa_log_info(_("Exiting."));
            m->quit(m, 1);
            break;
    }
}

#if defined(HAVE_PWD_H) && defined(HAVE_GRP_H)

static int change_user(void) {
    struct passwd *pw;
    struct group * gr;
    int r;

    /* This function is called only in system-wide mode. It creates a
     * runtime dir in /var/run/ with proper UID/GID and drops privs
     * afterwards. */

    if (!(pw = getpwnam(PA_SYSTEM_USER))) {
        pa_log(_("Failed to find user '%s'."), PA_SYSTEM_USER);
        return -1;
    }

    if (!(gr = getgrnam(PA_SYSTEM_GROUP))) {
        pa_log(_("Failed to find group '%s'."), PA_SYSTEM_GROUP);
        return -1;
    }

    pa_log_info(_("Found user '%s' (UID %lu) and group '%s' (GID %lu)."),
                PA_SYSTEM_USER, (unsigned long) pw->pw_uid,
                PA_SYSTEM_GROUP, (unsigned long) gr->gr_gid);

    if (pw->pw_gid != gr->gr_gid) {
        pa_log(_("GID of user '%s' and of group '%s' don't match."), PA_SYSTEM_USER, PA_SYSTEM_GROUP);
        return -1;
    }

    if (strcmp(pw->pw_dir, PA_SYSTEM_RUNTIME_PATH) != 0)
        pa_log_warn(_("Home directory of user '%s' is not '%s', ignoring."), PA_SYSTEM_USER, PA_SYSTEM_RUNTIME_PATH);

    if (pa_make_secure_dir(PA_SYSTEM_RUNTIME_PATH, 0755, pw->pw_uid, gr->gr_gid) < 0) {
        pa_log(_("Failed to create '%s': %s"), PA_SYSTEM_RUNTIME_PATH, pa_cstrerror(errno));
        return -1;
    }

    if (pa_make_secure_dir(PA_SYSTEM_STATE_PATH, 0700, pw->pw_uid, gr->gr_gid) < 0) {
        pa_log(_("Failed to create '%s': %s"), PA_SYSTEM_STATE_PATH, pa_cstrerror(errno));
        return -1;
    }

    /* We don't create the config dir here, because we don't need to write to it */

    if (initgroups(PA_SYSTEM_USER, gr->gr_gid) != 0) {
        pa_log(_("Failed to change group list: %s"), pa_cstrerror(errno));
        return -1;
    }

#if defined(HAVE_SETRESGID)
    r = setresgid(gr->gr_gid, gr->gr_gid, gr->gr_gid);
#elif defined(HAVE_SETEGID)
    if ((r = setgid(gr->gr_gid)) >= 0)
        r = setegid(gr->gr_gid);
#elif defined(HAVE_SETREGID)
    r = setregid(gr->gr_gid, gr->gr_gid);
#else
#error "No API to drop privileges"
#endif

    if (r < 0) {
        pa_log(_("Failed to change GID: %s"), pa_cstrerror(errno));
        return -1;
    }

#if defined(HAVE_SETRESUID)
    r = setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid);
#elif defined(HAVE_SETEUID)
    if ((r = setuid(pw->pw_uid)) >= 0)
        r = seteuid(pw->pw_uid);
#elif defined(HAVE_SETREUID)
    r = setreuid(pw->pw_uid, pw->pw_uid);
#else
#error "No API to drop privileges"
#endif

    if (r < 0) {
        pa_log(_("Failed to change UID: %s"), pa_cstrerror(errno));
        return -1;
    }

    pa_set_env("USER", PA_SYSTEM_USER);
    pa_set_env("USERNAME", PA_SYSTEM_USER);
    pa_set_env("LOGNAME", PA_SYSTEM_USER);
    pa_set_env("HOME", PA_SYSTEM_RUNTIME_PATH);

    /* Relevant for pa_runtime_path() */
    if (!getenv("PULSE_RUNTIME_PATH"))
        pa_set_env("PULSE_RUNTIME_PATH", PA_SYSTEM_RUNTIME_PATH);

    if (!getenv("PULSE_CONFIG_PATH"))
        pa_set_env("PULSE_CONFIG_PATH", PA_SYSTEM_CONFIG_PATH);

    if (!getenv("PULSE_STATE_PATH"))
        pa_set_env("PULSE_STATE_PATH", PA_SYSTEM_STATE_PATH);

    pa_log_info(_("Successfully dropped root privileges."));

    return 0;
}

#else /* HAVE_PWD_H && HAVE_GRP_H */

static int change_user(void) {
    pa_log(_("System wide mode unsupported on this platform."));
    return -1;
}

#endif /* HAVE_PWD_H && HAVE_GRP_H */

#ifdef HAVE_SYS_RESOURCE_H

static int set_one_rlimit(const pa_rlimit *r, int resource, const char *name) {
    struct rlimit rl;
    pa_assert(r);

    if (!r->is_set)
        return 0;

    rl.rlim_cur = rl.rlim_max = r->value;

    if (setrlimit(resource, &rl) < 0) {
        pa_log_info(_("setrlimit(%s, (%u, %u)) failed: %s"), name, (unsigned) r->value, (unsigned) r->value, pa_cstrerror(errno));
        return -1;
    }

    return 0;
}

static void set_all_rlimits(const pa_daemon_conf *conf) {
    set_one_rlimit(&conf->rlimit_fsize, RLIMIT_FSIZE, "RLIMIT_FSIZE");
    set_one_rlimit(&conf->rlimit_data, RLIMIT_DATA, "RLIMIT_DATA");
    set_one_rlimit(&conf->rlimit_stack, RLIMIT_STACK, "RLIMIT_STACK");
    set_one_rlimit(&conf->rlimit_core, RLIMIT_CORE, "RLIMIT_CORE");
#ifdef RLIMIT_RSS
    set_one_rlimit(&conf->rlimit_rss, RLIMIT_RSS, "RLIMIT_RSS");
#endif
#ifdef RLIMIT_NPROC
    set_one_rlimit(&conf->rlimit_nproc, RLIMIT_NPROC, "RLIMIT_NPROC");
#endif
#ifdef RLIMIT_NOFILE
    set_one_rlimit(&conf->rlimit_nofile, RLIMIT_NOFILE, "RLIMIT_NOFILE");
#endif
#ifdef RLIMIT_MEMLOCK
    set_one_rlimit(&conf->rlimit_memlock, RLIMIT_MEMLOCK, "RLIMIT_MEMLOCK");
#endif
#ifdef RLIMIT_AS
    set_one_rlimit(&conf->rlimit_as, RLIMIT_AS, "RLIMIT_AS");
#endif
#ifdef RLIMIT_LOCKS
    set_one_rlimit(&conf->rlimit_locks, RLIMIT_LOCKS, "RLIMIT_LOCKS");
#endif
#ifdef RLIMIT_SIGPENDING
    set_one_rlimit(&conf->rlimit_sigpending, RLIMIT_SIGPENDING, "RLIMIT_SIGPENDING");
#endif
#ifdef RLIMIT_MSGQUEUE
    set_one_rlimit(&conf->rlimit_msgqueue, RLIMIT_MSGQUEUE, "RLIMIT_MSGQUEUE");
#endif
#ifdef RLIMIT_NICE
    set_one_rlimit(&conf->rlimit_nice, RLIMIT_NICE, "RLIMIT_NICE");
#endif
#ifdef RLIMIT_RTPRIO
    set_one_rlimit(&conf->rlimit_rtprio, RLIMIT_RTPRIO, "RLIMIT_RTPRIO");
#endif
#ifdef RLIMIT_RTTIME
    set_one_rlimit(&conf->rlimit_rttime, RLIMIT_RTTIME, "RLIMIT_RTTIME");
#endif
}
#endif

static char *check_configured_address(void) {
    char *default_server = NULL;
    pa_client_conf *c = pa_client_conf_new();

    pa_client_conf_load(c, NULL);
#ifdef HAVE_X11
    pa_client_conf_from_x11(c, NULL);
#endif
    pa_client_conf_env(c);

    if (c->default_server && *c->default_server)
        default_server = pa_xstrdup(c->default_server);

    pa_client_conf_free(c);

    return default_server;
}

#ifdef HAVE_DBUS
static pa_dbus_connection *register_dbus_name(pa_core *c, DBusBusType bus, const char* name) {
    DBusError error;
    pa_dbus_connection *conn;

    dbus_error_init(&error);

    if (!(conn = pa_dbus_bus_get(c, bus, &error)) || dbus_error_is_set(&error)) {
        pa_log_warn("Unable to contact D-Bus: %s: %s", error.name, error.message);
        goto fail;
    }

    if (dbus_bus_request_name(pa_dbus_connection_get(conn), name, DBUS_NAME_FLAG_DO_NOT_QUEUE, &error) == DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER) {
        pa_log_debug("Got %s!", name);
        return conn;
    }

    if (dbus_error_is_set(&error))
        pa_log_error("Failed to acquire %s: %s: %s", name, error.name, error.message);
    else
        pa_log_error("D-Bus name %s already taken.", name);

    /* PA cannot be started twice by the same user and hence we can
     * ignore mostly the case that a name is already taken. */

fail:
    if (conn)
        pa_dbus_connection_unref(conn);

    dbus_error_free(&error);
    return NULL;
}
#endif

int main(int argc, char *argv[]) {
    pa_core *c = NULL;
    pa_strbuf *buf = NULL;
    pa_daemon_conf *conf = NULL;
    pa_mainloop *mainloop = NULL;
    char *s;
    char *configured_address;
    int r = 0, retval = 1, d = 0;
    pa_bool_t valid_pid_file = FALSE;
    pa_bool_t ltdl_init = FALSE;
    int passed_fd = -1;
    const char *e;
#ifdef HAVE_FORK
    int daemon_pipe[2] = { -1, -1 };
    int daemon_pipe2[2] = { -1, -1 };
#endif
#ifdef OS_IS_WIN32
    pa_time_event *win32_timer;
    struct timeval win32_tv;
#endif
    int autospawn_fd = -1;
    pa_bool_t autospawn_locked = FALSE;
#ifdef HAVE_DBUS
    pa_dbusobj_server_lookup *server_lookup = NULL; /* /org/pulseaudio/server_lookup */
    pa_dbus_connection *lookup_service_bus = NULL; /* Always the user bus. */
    pa_dbus_connection *server_bus = NULL; /* The bus where we reserve org.pulseaudio.Server, either the user or the system bus. */
    pa_bool_t start_server;
#endif

    pa_log_set_ident("pulseaudio");
    pa_log_set_level(PA_LOG_NOTICE);
    pa_log_set_flags(PA_LOG_COLORS|PA_LOG_PRINT_FILE|PA_LOG_PRINT_LEVEL, PA_LOG_RESET);

#if defined(__linux__) && defined(__OPTIMIZE__)
    /*
       Disable lazy relocations to make usage of external libraries
       more deterministic for our RT threads. We abuse __OPTIMIZE__ as
       a check whether we are a debug build or not. This all is
       admittedly a bit snake-oilish.
    */

    if (!getenv("LD_BIND_NOW")) {
        char *rp;
        char *canonical_rp;

        /* We have to execute ourselves, because the libc caches the
         * value of $LD_BIND_NOW on initialization. */

        pa_set_env("LD_BIND_NOW", "1");

        if ((canonical_rp = pa_realpath(PA_BINARY))) {

            if ((rp = pa_readlink("/proc/self/exe"))) {

                if (pa_streq(rp, canonical_rp))
                    pa_assert_se(execv(rp, argv) == 0);
                else
                    pa_log_warn("/proc/self/exe does not point to %s, cannot self execute. Are you playing games?", canonical_rp);

                pa_xfree(rp);

            } else
                pa_log_warn("Couldn't read /proc/self/exe, cannot self execute. Running in a chroot()?");

            pa_xfree(canonical_rp);

        } else
            pa_log_warn("Couldn't canonicalize binary path, cannot self execute.");
    }
#endif

    if ((e = getenv("PULSE_PASSED_FD"))) {
        passed_fd = atoi(e);

        if (passed_fd <= 2)
            passed_fd = -1;
    }

    /* We might be autospawned, in which case have no idea in which
     * context we have been started. Let's cleanup our execution
     * context as good as possible */

    pa_reset_personality();
    pa_drop_root();
    pa_close_all(passed_fd, -1);
    pa_reset_sigs(-1);
    pa_unblock_sigs(-1);
    pa_reset_priority();

    setlocale(LC_ALL, "");
    pa_init_i18n();

    conf = pa_daemon_conf_new();

    if (pa_daemon_conf_load(conf, NULL) < 0)
        goto finish;

    if (pa_daemon_conf_env(conf) < 0)
        goto finish;

    if (pa_cmdline_parse(conf, argc, argv, &d) < 0) {
        pa_log(_("Failed to parse command line."));
        goto finish;
    }

    pa_log_set_level(conf->log_level);
    pa_log_set_target(conf->auto_log_target ? PA_LOG_STDERR : conf->log_target);
    if (conf->log_meta)
        pa_log_set_flags(PA_LOG_PRINT_META, PA_LOG_SET);
    if (conf->log_time)
        pa_log_set_flags(PA_LOG_PRINT_TIME, PA_LOG_SET);
    pa_log_set_show_backtrace(conf->log_backtrace);

#ifdef HAVE_DBUS
    /* conf->system_instance and conf->local_server_type control almost the
     * same thing; make them agree about what is requested. */
    switch (conf->local_server_type) {
        case PA_SERVER_TYPE_UNSET:
            conf->local_server_type = conf->system_instance ? PA_SERVER_TYPE_SYSTEM : PA_SERVER_TYPE_USER;
            break;
        case PA_SERVER_TYPE_USER:
        case PA_SERVER_TYPE_NONE:
            conf->system_instance = FALSE;
            break;
        case PA_SERVER_TYPE_SYSTEM:
            conf->system_instance = TRUE;
            break;
        default:
            pa_assert_not_reached();
    }

    start_server = conf->local_server_type == PA_SERVER_TYPE_USER || (getuid() == 0 && conf->local_server_type == PA_SERVER_TYPE_SYSTEM);

    if (!start_server && conf->local_server_type == PA_SERVER_TYPE_SYSTEM) {
        pa_log_notice(_("System mode refused for non-root user. Only starting the D-Bus server lookup service."));
        conf->system_instance = FALSE;
    }
#endif

    LTDL_SET_PRELOADED_SYMBOLS();
    pa_ltdl_init();
    ltdl_init = TRUE;

    if (conf->dl_search_path)
        lt_dlsetsearchpath(conf->dl_search_path);

#ifdef OS_IS_WIN32
    {
        WSADATA data;
        WSAStartup(MAKEWORD(2, 0), &data);
    }
#endif

    pa_random_seed();

    switch (conf->cmd) {
        case PA_CMD_DUMP_MODULES:
            pa_dump_modules(conf, argc-d, argv+d);
            retval = 0;
            goto finish;

        case PA_CMD_DUMP_CONF: {

            if (d < argc) {
                pa_log("Too many arguments.\n");
                goto finish;
            }

            s = pa_daemon_conf_dump(conf);
            fputs(s, stdout);
            pa_xfree(s);
            retval = 0;
            goto finish;
        }

        case PA_CMD_DUMP_RESAMPLE_METHODS: {
            int i;

            if (d < argc) {
                pa_log("Too many arguments.\n");
                goto finish;
            }

            for (i = 0; i < PA_RESAMPLER_MAX; i++)
                if (pa_resample_method_supported(i))
                    printf("%s\n", pa_resample_method_to_string(i));

            retval = 0;
            goto finish;
        }

        case PA_CMD_HELP :
            pa_cmdline_help(argv[0]);
            retval = 0;
            goto finish;

        case PA_CMD_VERSION :

            if (d < argc) {
                pa_log("Too many arguments.\n");
                goto finish;
            }

            printf(PACKAGE_NAME" "PACKAGE_VERSION"\n");
            retval = 0;
            goto finish;

        case PA_CMD_CHECK: {
            pid_t pid;

            if (d < argc) {
                pa_log("Too many arguments.\n");
                goto finish;
            }

            if (pa_pid_file_check_running(&pid, "pulseaudio") < 0)
                pa_log_info(_("Daemon not running"));
            else {
                pa_log_info(_("Daemon running as PID %u"), pid);
                retval = 0;
            }

            goto finish;

        }
        case PA_CMD_KILL:

            if (d < argc) {
                pa_log("Too many arguments.\n");
                goto finish;
            }

            if (pa_pid_file_kill(SIGINT, NULL, "pulseaudio") < 0)
                pa_log(_("Failed to kill daemon: %s"), pa_cstrerror(errno));
            else
                retval = 0;

            goto finish;

        case PA_CMD_CLEANUP_SHM:

            if (d < argc) {
                pa_log("Too many arguments.\n");
                goto finish;
            }

            if (pa_shm_cleanup() >= 0)
                retval = 0;

            goto finish;

        default:
            pa_assert(conf->cmd == PA_CMD_DAEMON || conf->cmd == PA_CMD_START);
    }

    if (d < argc) {
        pa_log("Too many arguments.\n");
        goto finish;
    }

#ifdef HAVE_GETUID
    if (getuid() == 0 && !conf->system_instance)
        pa_log_warn(_("This program is not intended to be run as root (unless --system is specified)."));
#ifndef HAVE_DBUS /* A similar, only a notice worthy check was done earlier, if D-Bus is enabled. */
    else if (getuid() != 0 && conf->system_instance) {
        pa_log(_("Root privileges required."));
        goto finish;
    }
#endif
#endif  /* HAVE_GETUID */

    if (conf->cmd == PA_CMD_START && conf->system_instance) {
        pa_log(_("--start not supported for system instances."));
        goto finish;
    }

    if (conf->cmd == PA_CMD_START && (configured_address = check_configured_address())) {
        /* There is an server address in our config, but where did it come from?
         * By default a standard X11 login will load module-x11-publish which will
         * inject PULSE_SERVER X11 property. If the PA daemon crashes, we will end
         * up hitting this code path. So we have to check to see if our configured_address
         * is the same as the value that would go into this property so that we can
         * recover (i.e. autospawn) from a crash.
         */
        char *ufn;
        pa_bool_t start_anyway = FALSE;

        if ((ufn = pa_runtime_path(PA_NATIVE_DEFAULT_UNIX_SOCKET))) {
            char *id;

            if ((id = pa_machine_id())) {
                pa_strlist *server_list;
                char formatted_ufn[256];

                pa_snprintf(formatted_ufn, sizeof(formatted_ufn), "{%s}unix:%s", id, ufn);
                pa_xfree(id);

                if ((server_list = pa_strlist_parse(configured_address))) {
                    char *u = NULL;

                    /* We only need to check the first server */
                    server_list = pa_strlist_pop(server_list, &u);
                    pa_strlist_free(server_list);

                    start_anyway = (u && pa_streq(formatted_ufn, u));
                    pa_xfree(u);
                }
            }
            pa_xfree(ufn);
        }

        if (!start_anyway) {
            pa_log_notice(_("User-configured server at %s, refusing to start/autospawn."), configured_address);
            pa_xfree(configured_address);
            retval = 0;
            goto finish;
        }

        pa_log_notice(_("User-configured server at %s, which appears to be local. Probing deeper."), configured_address);
        pa_xfree(configured_address);
    }

    if (conf->system_instance && !conf->disallow_exit)
        pa_log_warn(_("Running in system mode, but --disallow-exit not set!"));

    if (conf->system_instance && !conf->disallow_module_loading)
        pa_log_warn(_("Running in system mode, but --disallow-module-loading not set!"));

    if (conf->system_instance && !conf->disable_shm) {
        pa_log_notice(_("Running in system mode, forcibly disabling SHM mode!"));
        conf->disable_shm = TRUE;
    }

    if (conf->system_instance && conf->exit_idle_time >= 0) {
        pa_log_notice(_("Running in system mode, forcibly disabling exit idle time!"));
        conf->exit_idle_time = -1;
    }

    if (conf->cmd == PA_CMD_START) {
        /* If we shall start PA only when it is not running yet, we
         * first take the autospawn lock to make things
         * synchronous. */

        if ((autospawn_fd = pa_autospawn_lock_init()) < 0) {
            pa_log("Failed to initialize autospawn lock");
            goto finish;
        }

        if ((pa_autospawn_lock_acquire(TRUE) < 0)) {
            pa_log("Failed to acquire autospawn lock");
            goto finish;
        }

        autospawn_locked = TRUE;
    }

    if (conf->daemonize) {
#ifdef HAVE_FORK
        pid_t child;
#endif

        if (pa_stdio_acquire() < 0) {
            pa_log(_("Failed to acquire stdio."));
            goto finish;
        }

#ifdef HAVE_FORK
        if (pipe(daemon_pipe) < 0) {
            pa_log(_("pipe() failed: %s"), pa_cstrerror(errno));
            goto finish;
        }

        if ((child = fork()) < 0) {
            pa_log(_("fork() failed: %s"), pa_cstrerror(errno));
            pa_close_pipe(daemon_pipe);
            goto finish;
        }

        if (child != 0) {
            ssize_t n;
            /* Father */

            pa_assert_se(pa_close(daemon_pipe[1]) == 0);
            daemon_pipe[1] = -1;

            if ((n = pa_loop_read(daemon_pipe[0], &retval, sizeof(retval), NULL)) != sizeof(retval)) {

                if (n < 0)
                    pa_log(_("read() failed: %s"), pa_cstrerror(errno));

                retval = 1;
            }

            if (retval)
                pa_log(_("Daemon startup failed."));
            else
                pa_log_info(_("Daemon startup successful."));

            goto finish;
        }

        if (autospawn_fd >= 0) {
            /* The lock file is unlocked from the parent, so we need
             * to close it in the child */

            pa_autospawn_lock_release();
            pa_autospawn_lock_done(TRUE);

            autospawn_locked = FALSE;
            autospawn_fd = -1;
        }

        pa_assert_se(pa_close(daemon_pipe[0]) == 0);
        daemon_pipe[0] = -1;
#endif

        if (conf->auto_log_target)
            pa_log_set_target(PA_LOG_SYSLOG);

#ifdef HAVE_SETSID
        if (setsid() < 0) {
            pa_log(_("setsid() failed: %s"), pa_cstrerror(errno));
            goto finish;
        }
#endif

#ifdef HAVE_FORK
        /* We now are a session and process group leader. Let's fork
         * again and let the father die, so that we'll become a
         * process that can never acquire a TTY again, in a session and
         * process group without leader */

        if (pipe(daemon_pipe2) < 0) {
            pa_log(_("pipe() failed: %s"), pa_cstrerror(errno));
            goto finish;
        }

        if ((child = fork()) < 0) {
            pa_log(_("fork() failed: %s"), pa_cstrerror(errno));
            pa_close_pipe(daemon_pipe2);
            goto finish;
        }

        if (child != 0) {
            ssize_t n;
            /* Father */

            pa_assert_se(pa_close(daemon_pipe2[1]) == 0);
            daemon_pipe2[1] = -1;

            if ((n = pa_loop_read(daemon_pipe2[0], &retval, sizeof(retval), NULL)) != sizeof(retval)) {

                if (n < 0)
                    pa_log(_("read() failed: %s"), pa_cstrerror(errno));

                retval = 1;
            }

            /* We now have to take care of signalling the first fork with
             * the return value we've received from this fork... */
            pa_assert(daemon_pipe[1] >= 0);

            pa_loop_write(daemon_pipe[1], &retval, sizeof(retval), NULL);
            pa_close(daemon_pipe[1]);
            daemon_pipe[1] = -1;

            goto finish;
        }

        pa_assert_se(pa_close(daemon_pipe2[0]) == 0);
        daemon_pipe2[0] = -1;

        /* We no longer need the (first) daemon_pipe as it's handled in our child above */
        pa_close_pipe(daemon_pipe);
#endif

#ifdef SIGTTOU
        signal(SIGTTOU, SIG_IGN);
#endif
#ifdef SIGTTIN
        signal(SIGTTIN, SIG_IGN);
#endif
#ifdef SIGTSTP
        signal(SIGTSTP, SIG_IGN);
#endif

        pa_nullify_stdfds();
    }

    pa_set_env_and_record("PULSE_INTERNAL", "1");
    pa_assert_se(chdir("/") == 0);
    umask(0022);

#ifdef HAVE_SYS_RESOURCE_H
    set_all_rlimits(conf);
#endif
    pa_rtclock_hrtimer_enable();

    pa_raise_priority(conf->nice_level);

    if (conf->system_instance)
        if (change_user() < 0)
            goto finish;

    pa_set_env_and_record("PULSE_SYSTEM", conf->system_instance ? "1" : "0");

    pa_log_info(_("This is PulseAudio %s"), PACKAGE_VERSION);
    pa_log_debug(_("Compilation host: %s"), CANONICAL_HOST);
    pa_log_debug(_("Compilation CFLAGS: %s"), PA_CFLAGS);

    s = pa_uname_string();
    pa_log_debug(_("Running on host: %s"), s);
    pa_xfree(s);

    pa_log_debug(_("Found %u CPUs."), pa_ncpus());

    pa_log_info(_("Page size is %lu bytes"), (unsigned long) PA_PAGE_SIZE);

#ifdef HAVE_VALGRIND_MEMCHECK_H
    pa_log_debug(_("Compiled with Valgrind support: yes"));
#else
    pa_log_debug(_("Compiled with Valgrind support: no"));
#endif

    pa_log_debug(_("Running in valgrind mode: %s"), pa_yes_no(pa_in_valgrind()));

    pa_log_debug(_("Running in VM: %s"), pa_yes_no(pa_running_in_vm()));

#ifdef __OPTIMIZE__
    pa_log_debug(_("Optimized build: yes"));
#else
    pa_log_debug(_("Optimized build: no"));
#endif

#ifdef NDEBUG
    pa_log_debug(_("NDEBUG defined, all asserts disabled."));
#elif defined(FASTPATH)
    pa_log_debug(_("FASTPATH defined, only fast path asserts disabled."));
#else
    pa_log_debug(_("All asserts enabled."));
#endif

    if (!(s = pa_machine_id())) {
        pa_log(_("Failed to get machine ID"));
        goto finish;
    }
    pa_log_info(_("Machine ID is %s."), s);
    pa_xfree(s);

    if ((s = pa_session_id())) {
        pa_log_info(_("Session ID is %s."), s);
        pa_xfree(s);
    }

    if (!(s = pa_get_runtime_dir()))
        goto finish;
    pa_log_info(_("Using runtime directory %s."), s);
    pa_xfree(s);

    if (!(s = pa_get_state_dir()))
        goto finish;
    pa_log_info(_("Using state directory %s."), s);
    pa_xfree(s);

    pa_log_info(_("Using modules directory %s."), conf->dl_search_path);

    pa_log_info(_("Running in system mode: %s"), pa_yes_no(pa_in_system_mode()));

    if (pa_in_system_mode())
        pa_log_warn(_("OK, so you are running PA in system mode. Please note that you most likely shouldn't be doing that.\n"
                      "If you do it nonetheless then it's your own fault if things don't work as expected.\n"
                      "Please read http://pulseaudio.org/wiki/WhatIsWrongWithSystemMode for an explanation why system mode is usually a bad idea."));

    if (conf->use_pid_file) {
        int z;

        if ((z = pa_pid_file_create("pulseaudio")) != 0) {

            if (conf->cmd == PA_CMD_START && z > 0) {
                /* If we are already running and with are run in
                 * --start mode, then let's return this as success. */

                retval = 0;
                goto finish;
            }

            pa_log(_("pa_pid_file_create() failed."));
            goto finish;
        }

        valid_pid_file = TRUE;
    }

    pa_disable_sigpipe();

    if (pa_rtclock_hrtimer())
        pa_log_info(_("Fresh high-resolution timers available! Bon appetit!"));
    else
        pa_log_info(_("Dude, your kernel stinks! The chef's recommendation today is Linux with high-resolution timers enabled!"));

    if (conf->lock_memory) {
#ifdef HAVE_SYS_MMAN_H
        if (mlockall(MCL_FUTURE) < 0)
            pa_log_warn("mlockall() failed: %s", pa_cstrerror(errno));
        else
            pa_log_info("Successfully locked process into memory.");
#else
        pa_log_warn("Memory locking requested but not supported on platform.");
#endif
    }

    pa_memtrap_install();

    pa_assert_se(mainloop = pa_mainloop_new());

    if (!(c = pa_core_new(pa_mainloop_get_api(mainloop), !conf->disable_shm, conf->shm_size))) {
        pa_log(_("pa_core_new() failed."));
        goto finish;
    }

    c->default_sample_spec = conf->default_sample_spec;
    c->default_channel_map = conf->default_channel_map;
    c->default_n_fragments = conf->default_n_fragments;
    c->default_fragment_size_msec = conf->default_fragment_size_msec;
    c->deferred_volume_safety_margin_usec = conf->deferred_volume_safety_margin_usec;
    c->deferred_volume_extra_delay_usec = conf->deferred_volume_extra_delay_usec;
    c->exit_idle_time = conf->exit_idle_time;
    c->scache_idle_time = conf->scache_idle_time;
    c->resample_method = conf->resample_method;
    c->realtime_priority = conf->realtime_priority;
    c->realtime_scheduling = !!conf->realtime_scheduling;
    c->disable_remixing = !!conf->disable_remixing;
    c->disable_lfe_remixing = !!conf->disable_lfe_remixing;
    c->deferred_volume = !!conf->deferred_volume;
    c->running_as_daemon = !!conf->daemonize;
    c->disallow_exit = conf->disallow_exit;
    c->flat_volumes = conf->flat_volumes;
#ifdef HAVE_DBUS
    c->server_type = conf->local_server_type;
#endif

    c->cpu_info.cpu_type = PA_CPU_UNDEFINED;
    if (!getenv("PULSE_NO_SIMD")) {
        if (pa_cpu_init_x86(&(c->cpu_info.flags.x86)))
            c->cpu_info.cpu_type = PA_CPU_X86;
        if (pa_cpu_init_arm(&(c->cpu_info.flags.arm)))
            c->cpu_info.cpu_type = PA_CPU_ARM;
	pa_cpu_init_orc(c->cpu_info);
    }

    pa_assert_se(pa_signal_init(pa_mainloop_get_api(mainloop)) == 0);
    pa_signal_new(SIGINT, signal_callback, c);
    pa_signal_new(SIGTERM, signal_callback, c);
#ifdef SIGUSR1
    pa_signal_new(SIGUSR1, signal_callback, c);
#endif
#ifdef SIGUSR2
    pa_signal_new(SIGUSR2, signal_callback, c);
#endif
#ifdef SIGHUP
    pa_signal_new(SIGHUP, signal_callback, c);
#endif

#ifdef OS_IS_WIN32
    win32_timer = pa_mainloop_get_api(mainloop)->time_new(pa_mainloop_get_api(mainloop), pa_gettimeofday(&win32_tv), message_cb, NULL);
#endif

    if (!conf->no_cpu_limit)
        pa_assert_se(pa_cpu_limit_init(pa_mainloop_get_api(mainloop)) == 0);

    buf = pa_strbuf_new();

#ifdef HAVE_DBUS
    if (start_server) {
#endif
        if (conf->load_default_script_file) {
            FILE *f;

            if ((f = pa_daemon_conf_open_default_script_file(conf))) {
                r = pa_cli_command_execute_file_stream(c, f, buf, &conf->fail);
                fclose(f);
            }
        }

        if (r >= 0)
            r = pa_cli_command_execute(c, conf->script_commands, buf, &conf->fail);

        pa_log_error("%s", s = pa_strbuf_tostring_free(buf));
        pa_xfree(s);

        if (r < 0 && conf->fail) {
            pa_log(_("Failed to initialize daemon."));
            goto finish;
        }

        if (!c->modules || pa_idxset_size(c->modules) == 0) {
            pa_log(_("Daemon startup without any loaded modules, refusing to work."));
            goto finish;
        }
#ifdef HAVE_DBUS
    } else {
        /* When we just provide the D-Bus server lookup service, we don't want
         * any modules to be loaded. We haven't loaded any so far, so one might
         * think there's no way to contact the server, but receiving certain
         * signals could still cause modules to load. */
        conf->disallow_module_loading = TRUE;
    }
#endif

    /* We completed the initial module loading, so let's disable it
     * from now on, if requested */
    c->disallow_module_loading = !!conf->disallow_module_loading;

#ifdef HAVE_DBUS
    if (!conf->system_instance) {
        if (!(server_lookup = pa_dbusobj_server_lookup_new(c)))
            goto finish;
        if (!(lookup_service_bus = register_dbus_name(c, DBUS_BUS_SESSION, "org.PulseAudio1")))
            goto finish;
    }

    if (start_server && !(server_bus = register_dbus_name(c, conf->system_instance ? DBUS_BUS_SYSTEM : DBUS_BUS_SESSION, "org.pulseaudio.Server")))
        goto finish;
#endif

#ifdef HAVE_FORK
    if (daemon_pipe2[1] >= 0) {
        int ok = 0;
        pa_loop_write(daemon_pipe2[1], &ok, sizeof(ok), NULL);
        pa_close(daemon_pipe2[1]);
        daemon_pipe2[1] = -1;
    }
#endif

    pa_log_info(_("Daemon startup complete."));

    retval = 0;
    if (pa_mainloop_run(mainloop, &retval) < 0)
        goto finish;

    pa_log_info(_("Daemon shutdown initiated."));

finish:
#ifdef HAVE_DBUS
    if (server_bus)
        pa_dbus_connection_unref(server_bus);
    if (lookup_service_bus)
        pa_dbus_connection_unref(lookup_service_bus);
    if (server_lookup)
        pa_dbusobj_server_lookup_free(server_lookup);
#endif

    if (autospawn_fd >= 0) {
        if (autospawn_locked)
            pa_autospawn_lock_release();

        pa_autospawn_lock_done(FALSE);
    }

#ifdef OS_IS_WIN32
    if (mainloop && win32_timer)
        pa_mainloop_get_api(mainloop)->time_free(win32_timer);
#endif

    if (c) {
        /* Ensure all the modules/samples are unloaded when the core is still ref'ed,
         * as unlink callback hooks in modules may need the core to be ref'ed */
        pa_module_unload_all(c);
        pa_scache_free_all(c);

        pa_core_unref(c);
        pa_log_info(_("Daemon terminated."));
    }

    if (!conf->no_cpu_limit)
        pa_cpu_limit_done();

    pa_signal_done();

#ifdef HAVE_FORK
    /* If we have daemon_pipe[1] still open, this means we've failed after
     * the first fork, but before the second. Therefore just write to it. */
    if (daemon_pipe[1] >= 0)
        pa_loop_write(daemon_pipe[1], &retval, sizeof(retval), NULL);
    else if (daemon_pipe2[1] >= 0)
        pa_loop_write(daemon_pipe2[1], &retval, sizeof(retval), NULL);

    pa_close_pipe(daemon_pipe2);
    pa_close_pipe(daemon_pipe);
#endif

    if (mainloop)
        pa_mainloop_free(mainloop);

    if (conf)
        pa_daemon_conf_free(conf);

    if (valid_pid_file)
        pa_pid_file_remove();

    /* This has no real purpose except making things valgrind-clean */
    pa_unset_env_recorded();

#ifdef OS_IS_WIN32
    WSACleanup();
#endif

    if (ltdl_init)
        pa_ltdl_done();

#ifdef HAVE_DBUS
    dbus_shutdown();
#endif

    return retval;
}