-/*
- * Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
/** \file server.c Paraslash's main server. */
* - Buffer trees: \ref buffer_tree.h,
* - Sideband API: \ref sideband.h,
* - Crypto: \ref crypt.h, \ref crypt_backend.h,
- * - Error subsystem: \ref error.h, \ref error2.c,
+ * - Error subsystem: \ref error.h,
* - Inter process communication: \ref ipc.h,
* - Forward error correction: \ref fec.h,
* - Daemons: \ref daemon.h,
#include <arpa/inet.h>
#include <sys/un.h>
#include <netdb.h>
+#include <lopsub.h>
+#include "server.lsg.h"
#include "para.h"
#include "error.h"
#include "crypt.h"
-#include "server.cmdline.h"
#include "afh.h"
#include "string.h"
#include "afs.h"
+#include "net.h"
#include "server.h"
#include "list.h"
#include "send.h"
#include "vss.h"
#include "config.h"
#include "close_on_fork.h"
-#include "net.h"
#include "daemon.h"
#include "ipc.h"
#include "fd.h"
#include "signal.h"
#include "user_list.h"
#include "color.h"
-#include "ggo.h"
#include "version.h"
-__printf_2_3 void (*para_log)(int, const char*, ...) = daemon_log;
+/** Array of error strings. */
+DEFINE_PARA_ERRLIST;
-/** Define the array of error lists needed by para_server. */
-INIT_SERVER_ERRLISTS;
+__printf_2_3 void (*para_log)(int, const char*, ...) = daemon_log;
/** Shut down non-authorized connections after that many seconds. */
#define ALARM_TIMEOUT 10
struct misc_meta_data *mmd;
/**
- * The configuration of para_server
+ * The active value for all config options of para_server.
*
- * It also contains the options for the audio file selector, audio format
- * handler and all supported senders.
+ * It is computed by merging the parse result of the command line options with
+ * the parse result of the config file.
*/
-struct server_args_info conf;
+struct lls_parse_result *server_lpr = NULL;
-/** A random value used in child context for authentication. */
+/* Command line options (no config file options). Used in handle_sighup(). */
+static struct lls_parse_result *cmdline_lpr;
+
+/**
+ * A random number used to "authenticate" the afs connection.
+ *
+ * para_server picks this number by random before it forks the afs process. The
+ * command handlers know this number as well and write it to the afs socket,
+ * together with the id of the shared memory area which contains the payload of
+ * the afs command. A local process has to know this number to abuse the afs
+ * service provided by the local socket.
+ */
uint32_t afs_socket_cookie;
/** The mutex protecting the shared memory area containing the mmd struct. */
int mmd_mutex;
-/** The file containing user information (public key, permissions). */
-static char *user_list_file = NULL;
+/* Serializes log output. */
+static int log_mutex;
static struct sched sched;
static struct signal_task *signal_task;
+/** The process id of the audio file selector process. */
+pid_t afs_pid = 0;
+
+/* The the main server process (parent of afs and the command handlers). */
+static pid_t server_pid;
+
+/**
+ * Tell whether the executing process is a command handler.
+ *
+ * Cleanup on exit must be performed differently for command handlers.
+ *
+ * \return True if the pid of the executing process is neither the server pid
+ * nor the afs pid.
+ */
+bool process_is_command_handler(void)
+{
+ pid_t pid = getpid();
+
+ return pid != afs_pid && pid != server_pid;
+}
+
/** The task responsible for server command handling. */
struct server_command_task {
/** TCP port on which para_server listens for connections. */
int listen_fd;
+ /* File descriptor for the accepted socket. */
+ int child_fd;
/** Copied from para_server's main function. */
int argc;
/** Argument vector passed to para_server's main function. */
return get_task_list(&sched);
}
-/*
- * setup shared memory area and get mutex for locking
- */
+static void pre_log_hook(void)
+{
+ mutex_lock(log_mutex);
+}
+
+static void post_log_hook(void)
+{
+ mutex_unlock(log_mutex);
+}
+
+/* Setup shared memory area and init mutexes */
static void init_ipc_or_die(void)
{
void *shm;
if (ret < 0)
goto err_out;
mmd_mutex = ret;
+ ret = mutex_new();
+ if (ret < 0)
+ goto destroy_mmd_mutex;
+ log_mutex = ret;
mmd->num_played = 0;
mmd->num_commands = 0;
mmd->vss_status_flags = VSS_NEXT;
mmd->new_vss_status_flags = VSS_NEXT;
return;
+destroy_mmd_mutex:
+ mutex_destroy(mmd_mutex);
err_out:
PARA_EMERG_LOG("%s\n", para_strerror(-ret));
exit(EXIT_FAILURE);
/**
* (Re-)read the server configuration files.
*
- * \param override Passed to gengetopt to activate the override feature.
+ * \param reload Whether config file overrides command line.
*
- * This function also re-opens the logfile and sets the global \a
- * user_list_file variable.
+ * This function also re-opens the logfile and the user list. On SIGHUP it is
+ * called from both server and afs context.
*/
-void parse_config_or_die(int override)
+void parse_config_or_die(bool reload)
{
- char *home = para_homedir();
int ret;
- char *cf;
+ char *cf = NULL, *errctx = NULL, *user_list_file = NULL;
+ void *map;
+ size_t sz;
+ int cf_argc;
+ char **cf_argv;
+ struct lls_parse_result *cf_lpr, *merged_lpr;
+ char *home = para_homedir();
- daemon_close_log();
- if (conf.config_file_given)
- cf = para_strdup(conf.config_file_arg);
+ if (OPT_GIVEN(CONFIG_FILE))
+ cf = para_strdup(OPT_STRING_VAL(CONFIG_FILE));
else
cf = make_message("%s/.paraslash/server.conf", home);
- free(user_list_file);
- if (!conf.user_list_given)
- user_list_file = make_message("%s/.paraslash/server.users", home);
- else
- user_list_file = para_strdup(conf.user_list_arg);
- ret = file_exists(cf);
- if (conf.config_file_given && !ret) {
- ret = -1;
- PARA_EMERG_LOG("can not read config file %s\n", cf);
- goto out;
+ if (!mmd || getpid() != afs_pid) {
+ if (OPT_GIVEN(USER_LIST))
+ user_list_file = para_strdup(OPT_STRING_VAL(USER_LIST));
+ else
+ user_list_file = make_message("%s/.paraslash/server.users", home);
}
- if (ret) {
- int tmp = conf.daemon_given;
- struct server_cmdline_parser_params params = {
- .override = override,
- .initialize = 0,
- .check_required = 1,
- .check_ambiguity = 0,
- .print_errors = !conf.daemon_given
- };
- server_cmdline_parser_config_file(cf, &conf, ¶ms);
- daemon_set_loglevel(conf.loglevel_arg);
- conf.daemon_given = tmp;
+ free(home);
+ ret = mmap_full_file(cf, O_RDONLY, &map, &sz, NULL);
+ if (ret < 0) {
+ if (ret != -E_EMPTY && ret != -ERRNO_TO_PARA_ERROR(ENOENT))
+ goto free_cf;
+ if (ret == -ERRNO_TO_PARA_ERROR(ENOENT) && OPT_GIVEN(CONFIG_FILE))
+ goto free_cf;
+ server_lpr = cmdline_lpr;
+ goto success;
}
- if (conf.logfile_given) {
- daemon_set_logfile(conf.logfile_arg);
+ ret = lls(lls_convert_config(map, sz, NULL, &cf_argv, &errctx));
+ para_munmap(map, sz);
+ if (ret < 0)
+ goto free_cf;
+ cf_argc = ret;
+ ret = lls(lls_parse(cf_argc, cf_argv, CMD_PTR, &cf_lpr, &errctx));
+ lls_free_argv(cf_argv);
+ if (ret < 0)
+ goto free_cf;
+ if (reload) /* config file overrides command line */
+ ret = lls(lls_merge(cf_lpr, cmdline_lpr, CMD_PTR, &merged_lpr,
+ &errctx));
+ else /* command line options override config file options */
+ ret = lls(lls_merge(cmdline_lpr, cf_lpr, CMD_PTR, &merged_lpr,
+ &errctx));
+ lls_free_parse_result(cf_lpr, CMD_PTR);
+ if (ret < 0)
+ goto free_cf;
+ if (server_lpr != cmdline_lpr)
+ lls_free_parse_result(server_lpr, CMD_PTR);
+ server_lpr = merged_lpr;
+success:
+ daemon_set_loglevel(ENUM_STRING_VAL(LOGLEVEL));
+ if (OPT_GIVEN(LOGFILE)) {
+ daemon_set_logfile(OPT_STRING_VAL(LOGFILE));
daemon_open_log_or_die();
}
-
- daemon_init_colors_or_die(conf.color_arg, color_arg_auto, color_arg_no,
- conf.logfile_given, conf.log_color_arg, conf.log_color_given);
+ if (daemon_init_colors_or_die(OPT_UINT32_VAL(COLOR), COLOR_AUTO,
+ COLOR_NO, OPT_GIVEN(LOGFILE))) {
+ int i;
+ for (i = 0; i < OPT_GIVEN(LOG_COLOR); i++)
+ daemon_set_log_color_or_die(lls_string_val(i,
+ OPT_RESULT(LOG_COLOR)));
+ }
daemon_set_flag(DF_LOG_PID);
daemon_set_flag(DF_LOG_LL);
daemon_set_flag(DF_LOG_TIME);
- if (conf.log_timing_given)
+ if (OPT_GIVEN(LOG_TIMING))
daemon_set_flag(DF_LOG_TIMING);
+ daemon_set_priority(OPT_UINT32_VAL(PRIORITY));
+ if (user_list_file)
+ user_list_init(user_list_file);
ret = 1;
-out:
+free_cf:
free(cf);
- free(home);
- if (ret > 0)
- return;
free(user_list_file);
- user_list_file = NULL;
- exit(EXIT_FAILURE);
+ if (ret < 0) {
+ if (errctx)
+ PARA_ERROR_LOG("%s\n", errctx);
+ free(errctx);
+ PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+ exit(EXIT_FAILURE);
+ }
}
/*
*/
static void handle_sighup(void)
{
+
PARA_NOTICE_LOG("SIGHUP\n");
- parse_config_or_die(1); /* reopens log */
- init_user_list(user_list_file); /* reload user list */
- if (mmd->afs_pid)
- kill(mmd->afs_pid, SIGHUP);
+ parse_config_or_die(true);
+ if (afs_pid != 0)
+ kill(afs_pid, SIGHUP);
}
static int signal_post_select(struct sched *s, __a_unused void *context)
{
- int signum = para_next_signal(&s->rfds);
+ int ret, signum;
+ ret = task_get_notification(signal_task->task);
+ if (ret < 0)
+ return ret;
+ signum = para_next_signal(&s->rfds);
switch (signum) {
case 0:
return 0;
case SIGCHLD:
for (;;) {
pid_t pid;
- int ret = para_reap_child(&pid);
+ ret = para_reap_child(&pid);
if (ret <= 0)
break;
- if (pid != mmd->afs_pid)
+ if (pid != afs_pid)
continue;
PARA_EMERG_LOG("fatal: afs died\n");
kill(0, SIGTERM);
PARA_EMERG_LOG("terminating on signal %d\n", signum);
kill(0, SIGTERM);
/*
- * We must wait for afs because afs catches SIGINT/SIGTERM.
- * Before reacting to the signal, afs might want to use the
+ * We must wait for all of our children to die. For the afs
+ * process or a command handler might want to use the
* shared memory area and the mmd mutex. If we destroy this
* mutex too early and afs tries to lock the shared memory
* area, the call to mutex_lock() will fail and terminate the
* afs process. This leads to dirty osl tables.
- *
- * There's no such problem with the other children of the
- * server process (the command handlers) as these reset their
- * SIGINT/SIGTERM handlers to the default action, i.e. these
- * processes get killed immediately by the above kill().
*/
- PARA_INFO_LOG("waiting for afs (pid %d) to die\n",
- (int)mmd->afs_pid);
- waitpid(mmd->afs_pid, NULL, 0);
+ PARA_INFO_LOG("waiting for child processes to die\n");
+ mutex_unlock(mmd_mutex);
+ while (wait(NULL) != -1 || errno != ECHILD)
+ ; /* still at least one child alive */
+ mutex_lock(mmd_mutex);
cleanup:
free(mmd->afd.afhi.chunk_table);
- close_listed_fds();
- mutex_destroy(mmd_mutex);
- shm_detach(mmd);
- exit(EXIT_FAILURE);
+ task_notify_all(s, E_DEADLY_SIGNAL);
+ return -E_DEADLY_SIGNAL;
}
return 0;
}
static int command_post_select(struct sched *s, void *context)
{
struct server_command_task *sct = context;
-
int new_fd, ret, i;
char *peer_name;
pid_t child_pid;
uint32_t *chunk_table;
+ ret = task_get_notification(sct->task);
+ if (ret < 0)
+ return ret;
ret = para_accept(sct->listen_fd, &s->rfds, NULL, 0, &new_fd);
if (ret <= 0)
goto out;
- peer_name = remote_name(new_fd);
- PARA_INFO_LOG("got connection from %s, forking\n", peer_name);
mmd->num_connects++;
mmd->active_connections++;
/*
/* parent keeps accepting connections */
return 0;
}
+ peer_name = remote_name(new_fd);
+ PARA_INFO_LOG("accepted connection from %s\n", peer_name);
/* mmd might already have changed at this point */
free(chunk_table);
- alarm(ALARM_TIMEOUT);
- close_listed_fds();
- signal_shutdown(signal_task);
+ sct->child_fd = new_fd;
/*
* put info on who we are serving into argv[0] to make
* client ip visible in top/ps
*/
for (i = sct->argc - 1; i >= 0; i--)
memset(sct->argv[i], 0, strlen(sct->argv[i]));
- sprintf(sct->argv[0], "para_server (serving %s)", peer_name);
- handle_connect(new_fd, peer_name);
- /* never reached*/
+ i = sct->argc - 1 - lls_num_inputs(cmdline_lpr);
+ sprintf(sct->argv[i], "para_server (serving %s)", peer_name);
+ /* ask other tasks to terminate */
+ task_notify_all(s, E_CHILD_CONTEXT);
+ /*
+ * After we return, the scheduler calls server_select() with a minimal
+ * timeout value, because the remaining tasks have a notification
+ * pending. Next it calls the ->post_select method of these tasks,
+ * which will return negative in view of the notification. This causes
+ * schedule() to return as there are no more runnable tasks.
+ *
+ * Note that semaphores are not inherited across a fork(), so we don't
+ * hold the lock at this point. Since server_select() drops the lock
+ * prior to calling para_select(), we need to acquire it here.
+ */
+ mutex_lock(mmd_mutex);
+ return -E_CHILD_CONTEXT;
out:
if (ret < 0)
PARA_CRIT_LOG("%s\n", para_strerror(-ret));
return 0;
}
-static void init_server_command_task(int argc, char **argv)
+static void init_server_command_task(struct server_command_task *sct,
+ int argc, char **argv)
{
int ret;
- static struct server_command_task server_command_task_struct,
- *sct = &server_command_task_struct;
PARA_NOTICE_LOG("initializing tcp command socket\n");
+ sct->child_fd = -1;
sct->argc = argc;
sct->argv = argv;
- ret = para_listen_simple(IPPROTO_TCP, conf.port_arg);
+ ret = para_listen_simple(IPPROTO_TCP, OPT_UINT32_VAL(PORT));
if (ret < 0)
goto err;
sct->listen_fd = ret;
static int init_afs(int argc, char **argv)
{
int ret, afs_server_socket[2];
- pid_t afs_pid;
+ char c;
- ret = socketpair(PF_UNIX, SOCK_DGRAM, 0, afs_server_socket);
+ ret = socketpair(PF_UNIX, SOCK_STREAM, 0, afs_server_socket);
if (ret < 0)
exit(EXIT_FAILURE);
get_random_bytes_or_die((unsigned char *)&afs_socket_cookie,
exit(EXIT_FAILURE);
if (afs_pid == 0) { /* child (afs) */
int i;
+
+ afs_pid = getpid();
+ crypt_shutdown();
+ user_list_deplete();
for (i = argc - 1; i >= 0; i--)
memset(argv[i], 0, strlen(argv[i]));
- sprintf(argv[0], "para_server (afs)");
+ i = argc - lls_num_inputs(cmdline_lpr) - 1;
+ sprintf(argv[i], "para_server (afs)");
close(afs_server_socket[0]);
- afs_init(afs_socket_cookie, afs_server_socket[1]);
+ afs_init(afs_server_socket[1]);
}
- mmd->afs_pid = afs_pid;
close(afs_server_socket[1]);
+ if (read(afs_server_socket[0], &c, 1) <= 0) {
+ PARA_EMERG_LOG("early afs exit\n");
+ exit(EXIT_FAILURE);
+ }
ret = mark_fd_nonblocking(afs_server_socket[0]);
if (ret < 0)
exit(EXIT_FAILURE);
return afs_server_socket[0];
}
-__noreturn static void print_help_and_die(void)
+static void handle_help_flags(void)
{
- struct ggo_help h = DEFINE_GGO_HELP(server);
- bool d = conf.detailed_help_given;
+ char *help;
+ bool d = OPT_GIVEN(DETAILED_HELP);
- ggo_print_help(&h, d? GPH_STANDARD_FLAGS_DETAILED : GPH_STANDARD_FLAGS);
- exit(0);
+ if (d)
+ help = lls_long_help(CMD_PTR);
+ else if (OPT_GIVEN(HELP))
+ help = lls_short_help(CMD_PTR);
+ else
+ return;
+ printf("%s\n", help);
+ free(help);
+ exit(EXIT_SUCCESS);
}
-static void server_init(int argc, char **argv)
+static void server_init(int argc, char **argv, struct server_command_task *sct)
{
- struct server_cmdline_parser_params params = {
- .override = 0,
- .initialize = 1,
- .check_required = 0,
- .check_ambiguity = 0,
- .print_errors = 1
- };
- int afs_socket;
+ int ret, afs_socket, daemon_pipe = -1;
+ char *errctx;
valid_fd_012();
- init_random_seed_or_die();
/* parse command line options */
- server_cmdline_parser_ext(argc, argv, &conf, ¶ms);
- daemon_set_loglevel(conf.loglevel_arg);
- version_handle_flag("server", conf.version_given);
- if (conf.help_given || conf.detailed_help_given)
- print_help_and_die();
- daemon_set_priority(conf.priority_arg);
- daemon_drop_privileges_or_die(conf.user_arg, conf.group_arg);
- /* parse config file, open log and set defaults */
- parse_config_or_die(0);
+ ret = lls(lls_parse(argc, argv, CMD_PTR, &cmdline_lpr, &errctx));
+ if (ret < 0)
+ goto fail;
+ server_lpr = cmdline_lpr;
+ daemon_set_loglevel(ENUM_STRING_VAL(LOGLEVEL));
+ daemon_drop_privileges_or_die(OPT_STRING_VAL(USER),
+ OPT_STRING_VAL(GROUP));
+ version_handle_flag("server", OPT_GIVEN(VERSION));
+ handle_help_flags();
+ parse_config_or_die(false);
+ /* become daemon */
+ if (OPT_GIVEN(DAEMON))
+ daemon_pipe = daemonize(true /* parent waits for SIGTERM */);
+ server_pid = getpid();
+ crypt_init();
daemon_log_welcome("server");
- init_ipc_or_die(); /* init mmd struct and mmd->lock */
+ init_ipc_or_die(); /* init mmd struct, mmd and log mutex */
daemon_set_start_time();
- init_user_list(user_list_file);
- /* become daemon */
- if (conf.daemon_given)
- daemonize(true /* parent waits for SIGTERM */);
+ daemon_set_hooks(pre_log_hook, post_log_hook);
PARA_NOTICE_LOG("initializing audio format handlers\n");
afh_init();
* Although afs uses its own signal handling we must ignore SIGUSR1
* _before_ the afs child process gets born by init_afs() below. It's
* racy to do this in the child because the parent might send SIGUSR1
- * before the child gets a chance to ignore this signal -- only the
- * good die young.
- */
- para_sigaction(SIGUSR1, SIG_IGN);
- /*
- * We have to block SIGCHLD before the afs process is being forked off.
- * Otherwise, para_server does not notice if afs dies before the
+ * before the child gets a chance to ignore this signal.
+ *
+ * We also have to block SIGCHLD before the afs process is created
+ * because otherwise para_server does not notice if afs dies before the
* SIGCHLD handler has been installed for the parent process by
* init_signal_task() below.
*/
+ para_sigaction(SIGUSR1, SIG_IGN);
para_block_signal(SIGCHLD);
PARA_NOTICE_LOG("initializing the audio file selector\n");
afs_socket = init_afs(argc, argv);
init_signal_task();
para_unblock_signal(SIGCHLD);
PARA_NOTICE_LOG("initializing virtual streaming system\n");
- init_vss_task(afs_socket, &sched);
- init_server_command_task(argc, argv);
- if (conf.daemon_given)
- kill(getppid(), SIGTERM);
+ vss_init(afs_socket, &sched);
+ init_server_command_task(sct, argc, argv);
+ if (daemon_pipe >= 0) {
+ if (write(daemon_pipe, "\0", 1) < 0) {
+ PARA_EMERG_LOG("daemon_pipe: %s", strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+ close(daemon_pipe);
+ }
PARA_NOTICE_LOG("server init complete\n");
+ return;
+fail:
+ assert(ret < 0);
+ if (errctx)
+ PARA_ERROR_LOG("%s\n", errctx);
+ PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+ exit(EXIT_FAILURE);
}
static void status_refresh(void)
prev_uptime = uptime;
prev_events = mmd->events;
mmd->vss_status_flags = mmd->new_vss_status_flags;
- PARA_DEBUG_LOG("%d events, forcing status update\n", mmd->events);
+ PARA_DEBUG_LOG("%u events, forcing status update\n", mmd->events);
killpg(0, SIGUSR1);
}
return ret;
}
+/**
+ * Deallocate all lopsub parse results.
+ *
+ * The server allocates a parse result for command line options and optionally
+ * a second parse result for the effective configuration, defined by merging
+ * the command line options with the options stored in the configuration file.
+ * This function frees both structures.
+ */
+void free_lpr(void)
+{
+ lls_free_parse_result(server_lpr, CMD_PTR);
+ if (server_lpr != cmdline_lpr)
+ lls_free_parse_result(cmdline_lpr, CMD_PTR);
+}
+
/**
* The main function of para_server.
*
int main(int argc, char *argv[])
{
int ret;
+ struct server_command_task server_command_task_struct,
+ *sct = &server_command_task_struct;
sched.default_timeout.tv_sec = 1;
sched.select_function = server_select;
- server_init(argc, argv);
+ server_init(argc, argv, sct);
mutex_lock(mmd_mutex);
ret = schedule(&sched);
+ /*
+ * We hold the mmd lock: it was re-acquired in server_select()
+ * after the select call.
+ */
+ mutex_unlock(mmd_mutex);
sched_shutdown(&sched);
- if (ret < 0) {
- PARA_EMERG_LOG("%s\n", para_strerror(-ret));
- exit(EXIT_FAILURE);
+ crypt_shutdown();
+ signal_shutdown(signal_task);
+ if (!process_is_command_handler()) { /* parent (server) */
+ mutex_destroy(mmd_mutex);
+ daemon_set_hooks(NULL, NULL); /* only one process remaining */
+ mutex_destroy(log_mutex);
+ deplete_close_on_fork_list();
+ if (ret < 0)
+ PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+ } else {
+ alarm(ALARM_TIMEOUT);
+ close_listed_fds();
+ ret = handle_connect(sct->child_fd);
}
- exit(EXIT_SUCCESS);
+ vss_shutdown();
+ shm_detach(mmd);
+ user_list_deplete();
+ free_lpr();
+ exit(ret < 0? EXIT_FAILURE : EXIT_SUCCESS);
}
projects / paraslash.git / blobdiff