Increase aggressiveness of the compress filter.
[paraslash.git] / server.c
index c7e6812..90dfc1f 100644 (file)
--- a/server.c
+++ b/server.c
@@ -1,47 +1,91 @@
 /*
- * Copyright (C) 1997-2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 1997-2008 Andre Noll <maan@systemlinux.org>
  *
- *     This program is free software; you can redistribute it and/or modify
- *     it under the terms of the GNU General Public License as published by
- *     the Free Software Foundation; either version 2 of the License, or
- *     (at your option) any later version.
- *
- *     This program 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 General Public License
- *     along with this program; if not, write to the Free Software
- *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
-/** \file server.c Paraslash's main server */
+/** \file server.c Paraslash's main server. */
 
 
-/** \mainpage Paraslash API Reference
+/**
+ * \mainpage Paraslash API Reference
+ *
+ * Starting points for getting an overview are
+ *
+ * probably:
+ *
+ *     - The main programs: \ref server.c, \ref audiod.c, \ref client.c,
+ *       \ref audioc.c, \ref fsck.c,
+ *     - Server: \ref server_command, \ref sender,
+ *     - Audio file selector: \ref audio_format_handler, \ref mood, \ref afs_table,
+ *     - Client: \ref receiver, \ref receiver_node, \ref filter, \ref filter_node.
+ *
+ *
+ * The gory details, listed by topic:
+ *
+ *     - Audio format handlers: \ref mp3_afh.c, \ref ogg_afh.c, \ref aac_afh.c,
+ *     - Decoders: \ref mp3dec.c, \ref oggdec.c, \ref aacdec.c,
+ *     - Volume normalizer: \ref compress.c,
+ *     - Output: \ref alsa_write.c, \ref osx_write.c,
+ *     - http: \ref http_recv.c, \ref http_send.c,
+ *     - ortp: \ref ortp_recv.c, \ref ortp_send.c,
+ *     - dccp: \ref dccp_recv.c, \ref dccp_send.c,
+ *     - Audio file selector: \ref afs.c, \ref aft.c, \ref mood.c,
+ *     - Afs structures: \ref afs_table, \ref audio_file_data,
+ *       \ref afs_info \ref afh_info,
+ *     - Afs tables: \ref aft.c, \ref mood.c, \ref playlist.c,
+ *       \ref attribute.c, \ref score.c,
+ *     - The virtual streaming system: \ref vss.c, \ref chunk_queue.c.
+ *
+ * Lower levels:
+ *
+ *     - Scheduling: \ref sched.c, \ref sched.h,
+ *     - Networking: \ref net.c,
+ *     - File descriptors: \ref fd.c,
+ *     - Signals: \ref signal.c,
+ *     - Daemons: \ref daemon.c,
+ *     - Strings: \ref string.c, \ref string.h,
+ *     - Time: \ref time.c,
+ *     - Spawning processes: \ref exec.c,
+ *     - Inter process communication: \ref ipc.c,
+ *     - The object storage layer: \ref osl.c,
+ *     - Blob tables: \ref blob.c,
+ *     - The error subssystem: \ref error.h.
+ *     - Access control for paraslash senders: \ref acl.c, \ref acl.h.
+ *
+ * Low-level data structures:
  *
- *  Good starting points for reading are probably \ref audio_file_selector,
- *  \ref sender, \ref receiver, \ref receiver_node, \ref filter, \ref
- *  filter_node.
+ *     - Doubly linked lists: \ref list.h,
+ *     - Red-black trees: \ref rbtree.h, \ref rbtree.c,
+ *     - Ring buffer: \ref ringbuffer.c, \ref ringbuffer.h,
+ *     - Hashing: \ref hash.h, \ref sha1.h, \ref sha1.c,
+ *     - Crypto: \ref crypt.c.
  *
  */
 
+#include <signal.h>
+#include <sys/types.h>
+#include <dirent.h>
 
-
+#include "para.h"
+#include "error.h"
 #include "server.cmdline.h"
-#include "db.h"
-#include "server.h"
+#include "afh.h"
+#include "string.h"
 #include "afs.h"
+#include "server.h"
+#include "vss.h"
 #include "config.h"
 #include "close_on_fork.h"
+#include "list.h"
 #include "send.h"
-#include "error.h"
 #include "net.h"
 #include "daemon.h"
-#include "string.h"
 #include "ipc.h"
 #include "fd.h"
+#include "sched.h"
+#include "signal.h"
+#include "user_list.h"
 
 /** define the array of error lists needed by para_server */
 INIT_SERVER_ERRLISTS;
@@ -49,48 +93,27 @@ INIT_SERVER_ERRLISTS;
 /** shut down non-authorized connections after that many seconds */
 #define ALARM_TIMEOUT 10
 
-/* these are exported to afs.c. command.c and to all selectors */
+/**
+ * Pointer to shared memory area for communication between para_server
+ * and its children. Exported to vss.c. command.c and to afs.
+ */
 struct misc_meta_data *mmd;
-/** the configuration of para_server
+
+/**
+ * the configuration of para_server
  *
- * It also contains the options for all audio file selectors and all supported
- * senders.
-*/
+ * It also contains the options for the audio file selector, audio format
+ * handler and all supported senders.
+ */
 struct server_args_info conf;
-char *user_list = NULL;
+
+/** the file containing user information (public key, permissions) */
+char *user_list_file = NULL;
+
 extern void dccp_send_init(struct sender *);
 extern void http_send_init(struct sender *);
 extern void ortp_send_init(struct sender *);
 
-/* TODO: This is better handled by autoconf */
-/** the list of supported audio file selectors */
-struct audio_file_selector selectors[] = {
-       {
-               .name = "random",
-               .init = random_selector_init,
-               .update_audio_file = NULL,
-       },
-       {
-               .name = "playlist",
-               .init = playlist_selector_init,
-               .update_audio_file = NULL,
-               .pre_select = NULL,
-               .post_select = NULL,
-       },
-#ifdef HAVE_MYSQL
-       {
-               .name = "mysql",
-               .init = mysql_selector_init,
-               .update_audio_file = NULL,
-               .pre_select = NULL,
-               .post_select = NULL,
-       },
-#endif
-       {
-               .name = NULL,
-       }
-};
-
 /** the list of supported senders */
 struct sender senders[] = {
        {
@@ -144,7 +167,7 @@ void para_log(int ll, const char* fmt,...)
                fprintf(outfd, "%i: ", ll);
        mypid = getpid();
        if (conf.loglevel_arg <= INFO)
-               fprintf(outfd, "(%d) ", mypid);
+               fprintf(outfd, "(%d) ", (int)mypid);
        va_start(argp, fmt);
        vfprintf(outfd, fmt, argp);
        va_end(argp);
@@ -172,27 +195,24 @@ static void shm_init(void)
                goto err_out;
        mmd_mutex = ret;
 
-       mmd->selector_num = 0;
        mmd->num_played = 0;
        mmd->num_commands = 0;
        mmd->events = 0;
        mmd->num_connects = 0;
        mmd->active_connections = 0;
-       strcpy(mmd->filename, "(none)");
-       mmd->audio_format = -1;
-       mmd->afs_status_flags = AFS_NEXT;
-       mmd->new_afs_status_flags = AFS_NEXT;
+       mmd->vss_status_flags = VSS_NEXT;
+       mmd->new_vss_status_flags = VSS_NEXT;
        mmd->sender_cmd_data.cmd_num = -1;
        return;
 err_out:
-       PARA_EMERG_LOG("%s", PARA_STRERROR(-ret));
+       PARA_EMERG_LOG("%s\n", para_strerror(-ret));
        exit(EXIT_FAILURE);
 }
 
 /**
  * lock the shared memory area containing the mmd struct
  *
- * \sa semop(2), struct misc_meta_data
+ * \sa semop(2), struct misc_meta_data.
  */
 void mmd_lock(void)
 {
@@ -218,14 +238,14 @@ static void parse_config(int override)
        char *cf;
 
        if (conf.config_file_given)
-               cf = conf.config_file_arg;
+               cf = para_strdup(conf.config_file_arg);
        else
                cf = make_message("%s/.paraslash/server.conf", home);
-       free(user_list);
+       free(user_list_file);
        if (!conf.user_list_given)
-               user_list = make_message("%s/.paraslash/server.users", home);
+               user_list_file = make_message("%s/.paraslash/server.users", home);
        else
-               user_list = para_strdup(conf.user_list_arg);
+               user_list_file = para_strdup(conf.user_list_arg);
        ret = stat(cf, &statbuf);
        if (ret && conf.config_file_given) {
                ret = -1;
@@ -234,15 +254,15 @@ static void parse_config(int override)
        }
        if (!ret) {
                int tmp = conf.daemon_given;
-               server_cmdline_parser_configfile(cf, &conf, override, 0, 0);
+               struct server_cmdline_parser_params params = {
+                       .override = override,
+                       .initialize = 0,
+                       .check_required = 0,
+                       .check_ambiguity = 0
+               };
+               server_cmdline_parser_config_file(cf, &conf, &params);
                conf.daemon_given = tmp;
        }
-       /* logfile */
-       if (!conf.logfile_given && conf.daemon_given) {
-               ret = -1;
-               PARA_EMERG_LOG("%s", "daemon, but no log file\n");
-               goto out;
-       }
        if (conf.logfile_given)
                logfile = open_log(conf.logfile_arg);
        ret = 1;
@@ -251,88 +271,111 @@ out:
        free(home);
        if (ret > 0)
                return;
-       free(user_list);
-       user_list = NULL;
+       free(user_list_file);
+       user_list_file = NULL;
        exit(EXIT_FAILURE);
 }
 
 static void setup_signal_handling(void)
 {
-       int ret = 0;
-
-       signal_pipe = para_signal_init();
-       PARA_NOTICE_LOG("%s", "setting up signal handlers\n");
-       ret += para_install_sighandler(SIGINT);
-       ret += para_install_sighandler(SIGTERM);
-       ret += para_install_sighandler(SIGHUP);
-       ret += para_install_sighandler(SIGCHLD);
-       ret += para_install_sighandler(SIGUSR1);
-       signal(SIGPIPE, SIG_IGN);
-       if (ret != 5) {
-               PARA_EMERG_LOG("%s", "could not install signal handlers\n");
-               exit(EXIT_FAILURE);
-       }
-}
-
-static void init_selector(void)
-{
-       int i, ret;
-
-       mmd->selector_change = -1; /* no change nec., set to new num by com_chs */
-       if (!conf.selector_given)
-               goto random;
-       for (i = 0; selectors[i].name; i++) {
-               if (strcmp(selectors[i].name, conf.selector_arg))
-                       continue;
-               PARA_NOTICE_LOG("initializing %s audio file selector\n",
-                       selectors[i].name);
-               ret = selectors[i].init(&selectors[i]);
-               if (ret < 0) {
-                       PARA_WARNING_LOG("%s", PARA_STRERROR(-ret));
-                       break;
-               }
-               mmd->selector_num = i;
-               return;
-       }
-       PARA_WARNING_LOG("%s", "falling back to the random selector\n");
-random:
-       mmd->selector_num = 0;
-       selectors[0].init(&selectors[0]); /* always successful */
+       signal_pipe = para_signal_init(); /* always successful */
+
+       PARA_NOTICE_LOG("setting up signal handlers\n");
+       if (para_install_sighandler(SIGINT) < 0)
+               goto err;
+       if (para_install_sighandler(SIGTERM) < 0)
+               goto err;
+       if (para_install_sighandler(SIGHUP) < 0)
+               goto err;
+       if (para_install_sighandler(SIGCHLD) < 0)
+               goto err;
+       if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
+               goto err;
+       if (signal(SIGUSR1, SIG_IGN) == SIG_ERR)
+               goto err;
+       add_close_on_fork_list(signal_pipe);
+       return;
+err:
+       PARA_EMERG_LOG("could not install signal handlers\n");
+       exit(EXIT_FAILURE);
 }
 
 static unsigned init_network(void)
 {
-       int sockfd = init_tcp_socket(conf.port_arg);
+       int fd, ret = para_listen(AF_UNSPEC, IPPROTO_TCP, conf.port_arg);
 
-       if (sockfd < 0)
-               exit(EXIT_FAILURE);
-       return sockfd;
+       if (ret < 0)
+               goto err;
+       fd = ret;
+       ret = mark_fd_nonblocking(fd);
+       if (ret < 0)
+               goto err;
+       add_close_on_fork_list(fd); /* child doesn't need the listener */
+       return fd;
+err:
+       PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+       exit(EXIT_FAILURE);
 }
 
 static void init_random_seed(void)
 {
-       int fd, ret = -1, len = sizeof(unsigned int);
        unsigned int seed;
+       int fd, ret = para_open("/dev/urandom", O_RDONLY, 0);
 
-       fd = open("/dev/urandom", O_RDONLY);
-       if (fd < 0)
+       if (ret < 0)
+               goto err;
+       fd = ret;
+       ret = read(fd, &seed, sizeof(seed));
+       if (ret < 0) {
+               ret = -ERRNO_TO_PARA_ERROR(errno);
                goto out;
-       ret = -2;
-       if (read(fd, &seed, len) != len)
+       }
+       if (ret != sizeof(seed)) {
+               ret = -ERRNO_TO_PARA_ERROR(EIO);
                goto out;
+       }
        srandom(seed);
        ret = 1;
 out:
-       if (fd >= 0)
-               close(fd);
-       if (ret > 0)
+       close(fd);
+       if (ret >= 0)
                return;
-       PARA_EMERG_LOG("can not seed pseudo random generator (ret = %d)\n",
-               ret);
+err:
+       PARA_EMERG_LOG("can not seed pseudo random number generator: %s\n",
+               para_strerror(-ret));
        exit(EXIT_FAILURE);
 }
 
-static unsigned do_inits(int argc, char **argv)
+uint32_t afs_socket_cookie;
+int afs_socket;
+static pid_t afs_pid;
+
+static void init_afs(void)
+{
+       int ret, afs_server_socket[2];
+
+       ret = socketpair(PF_UNIX, SOCK_DGRAM, 0, afs_server_socket);
+       if (ret < 0)
+               exit(EXIT_FAILURE);
+       afs_socket_cookie = para_random((uint32_t)-1);
+       afs_pid = fork();
+       if (afs_pid < 0)
+               exit(EXIT_FAILURE);
+       if (!afs_pid) { /* child (afs) */
+               close(afs_server_socket[0]);
+               afs_init(afs_socket_cookie, afs_server_socket[1]);
+       }
+       close(afs_server_socket[1]);
+       afs_socket = afs_server_socket[0];
+       ret = mark_fd_nonblocking(afs_socket);
+       if (ret < 0)
+               exit(EXIT_FAILURE);
+       add_close_on_fork_list(afs_socket);
+       PARA_INFO_LOG("afs_socket: %d, afs_socket_cookie: %u\n", afs_socket,
+               (unsigned) afs_socket_cookie);
+}
+
+static unsigned server_init(int argc, char **argv)
 {
        /* connector's address information */
        int sockfd;
@@ -340,57 +383,45 @@ static unsigned do_inits(int argc, char **argv)
        init_random_seed();
        /* parse command line options */
        server_cmdline_parser(argc, argv, &conf);
+       HANDLE_VERSION_FLAG("server", conf);
        para_drop_privileges(conf.user_arg, conf.group_arg);
        /* parse config file, open log and set defaults */
        parse_config(0);
        log_welcome("para_server", conf.loglevel_arg);
        shm_init(); /* init mmd struct */
        server_uptime(UPTIME_SET); /* reset server uptime */
+       init_user_list(user_list_file);
        /* become daemon */
        if (conf.daemon_given)
                daemon_init();
-       init_selector();
-       PARA_NOTICE_LOG("%s", "initializing audio file sender\n");
-       /* audio file sender */
-       afs_init();
+       PARA_NOTICE_LOG("initializing audio format handlers\n");
+       afh_init();
+       PARA_NOTICE_LOG("initializing virtual streaming system\n");
        mmd->server_pid = getpid();
        setup_signal_handling();
+       PARA_NOTICE_LOG("initializing the audio file selector\n");
+       init_afs();
+       vss_init();
        mmd_lock();
        /* init network socket */
-       PARA_NOTICE_LOG("%s", "initializing tcp command socket\n");
+       PARA_NOTICE_LOG("initializing tcp command socket\n");
        sockfd = init_network();
-       PARA_NOTICE_LOG("%s", "init complete\n");
+       PARA_NOTICE_LOG("server init complete\n");
        return sockfd;
 }
 
-static void change_selector(void)
-{
-       int ret, old = mmd->selector_num, new = mmd->selector_change;
-
-       selectors[old].shutdown();
-       ret = selectors[new].init(&selectors[new]);
-       mmd->selector_change = -1; /* reset */
-       if (ret >= 0) {
-               mmd->selector_num = new;
-               return;
-       }
-       /* init failed */
-       PARA_ERROR_LOG("%s -- switching to the random selector\n", PARA_STRERROR(-ret));
-       selectors[0].init(&selectors[0]);
-       mmd->selector_num = 0;
-}
-
 /*
  * called when server gets SIGHUP or when client invokes hup command.
  */
 static void handle_sighup(void)
 {
-       PARA_NOTICE_LOG("%s", "SIGHUP\n");
+       PARA_NOTICE_LOG("SIGHUP\n");
        close_log(logfile); /* gets reopened if necessary by parse_config */
        logfile = NULL;
        parse_config(1); /* reopens log */
-       mmd->selector_change = mmd->selector_num; /* do not change selector.. */
-       change_selector(); /* .. just reload */
+       init_user_list(user_list_file); /* reload user list */
+       if (afs_pid)
+               kill(afs_pid, SIGHUP);
 }
 
 static void status_refresh(void)
@@ -400,7 +431,7 @@ static void status_refresh(void)
 
        if (prev_events != mmd->events)
                goto out;
-       if (mmd->new_afs_status_flags != mmd->afs_status_flags)
+       if (mmd->new_vss_status_flags != mmd->vss_status_flags)
                goto out;
        if (uptime / 60 != prev_uptime / 60)
                goto out;
@@ -408,29 +439,35 @@ static void status_refresh(void)
 out:
        prev_uptime = uptime;
        prev_events = mmd->events;
-       mmd->afs_status_flags = mmd->new_afs_status_flags;
+       mmd->vss_status_flags = mmd->new_vss_status_flags;
        if (ret) {
-               PARA_DEBUG_LOG("%d events, forcing status update, af = %d\n",
-                       mmd->events, mmd->audio_format);
+               PARA_DEBUG_LOG("%d events, forcing status update\n",
+                       mmd->events);
                killpg(0, SIGUSR1);
        }
 }
 
-/*
- * MAIN
+/**
+ * the main function of para_server
+ *
+ * \param argc usual argument count
+ * \param argv usual argument vector
+ *
+ * \return EXIT_SUCCESS or EXIT_FAILURE
+ *
  */
 int main(int argc, char *argv[])
 {
        /* listen on sock_fd, new connection on new_fd */
        int sockfd, new_fd;
-       struct sockaddr_in their_addr;
+       char *peer_name;
        int i, max_fileno, ret;
        pid_t chld_pid;
        fd_set rfds, wfds;
        struct timeval *timeout;
 
        valid_fd_012();
-       sockfd = do_inits(argc, argv);
+       sockfd = server_init(argc, argv);
 repeat:
        FD_ZERO(&rfds);
        FD_ZERO(&wfds);
@@ -438,56 +475,55 @@ repeat:
        /* check socket and signal pipe in any case */
        para_fd_set(sockfd, &rfds, &max_fileno);
        para_fd_set(signal_pipe, &rfds, &max_fileno);
-       timeout = afs_preselect();
+       timeout = vss_preselect(&rfds, &wfds, &max_fileno);
        status_refresh();
        for (i = 0; senders[i].name; i++) {
-               if (senders[i].status != SENDER_ON)
-                       continue;
                if (!senders[i].pre_select)
                        continue;
-               senders[i].pre_select( &max_fileno, &rfds, &wfds);
-       }
-       if (selectors[mmd->selector_num].pre_select) {
-               ret = selectors[mmd->selector_num].pre_select(&rfds, &wfds);
-               max_fileno = PARA_MAX(max_fileno, ret);
+               senders[i].pre_select(&max_fileno, &rfds, &wfds);
        }
        mmd_unlock();
        ret = para_select(max_fileno + 1, &rfds, &wfds, timeout);
        mmd_lock();
-       if (mmd->selector_change >= 0)
-               change_selector();
-       if (selectors[mmd->selector_num].post_select)
-               selectors[mmd->selector_num].post_select(&rfds, &wfds);
+       vss_post_select(&rfds, &wfds);
        if (ret < 0)
                goto repeat;
        for (i = 0; senders[i].name; i++) {
-               if (senders[i].status != SENDER_ON)
-                       continue;
                if (!senders[i].post_select)
                        continue;
                senders[i].post_select(&rfds, &wfds);
        }
-       afs_send_chunk();
+       vss_send_chunk();
        status_refresh();
        if (FD_ISSET(signal_pipe, &rfds)) {
                int sig;
+               pid_t pid;
                sig = para_next_signal();
                switch (sig) {
                case SIGHUP:
                        handle_sighup();
                        break;
                case SIGCHLD:
-                       para_reap_children();
+                       for (;;) {
+                               ret = para_reap_child(&pid);
+                               if (ret <= 0)
+                                       break;
+                               if (pid != afs_pid)
+                                       continue;
+                               PARA_EMERG_LOG("fatal: afs died\n");
+                               goto genocide;
+                       }
                        break;
                /* die on sigint/sigterm. Kill all children too. */
                case SIGINT:
                case SIGTERM:
                        PARA_EMERG_LOG("terminating on signal %d\n", sig);
+genocide:
                        kill(0, SIGTERM);
-                       selectors[mmd->selector_num].shutdown();
                        mutex_destroy(mmd_mutex);
                        shm_detach(mmd);
                        shm_destroy(mmd_shm_id);
+
                        exit(EXIT_FAILURE);
                }
        }
@@ -502,17 +538,17 @@ repeat:
        if (!FD_ISSET(sockfd, &rfds))
                goto repeat;
 
-       new_fd = para_accept(sockfd, &their_addr, sizeof(struct sockaddr_in));
+       new_fd = para_accept(sockfd, NULL, 0);
        if (new_fd < 0)
                goto repeat;
-       PARA_INFO_LOG("got connection from %s, forking\n",
-               inet_ntoa(their_addr.sin_addr));
+       peer_name = remote_name(new_fd);
+       PARA_INFO_LOG("got connection from %s, forking\n", peer_name);
        mmd->num_connects++;
        mmd->active_connections++;
        random();
        chld_pid = fork();
        if (chld_pid < 0) {
-               PARA_CRIT_LOG("%s", "fork failed\n");
+               PARA_CRIT_LOG("fork failed\n");
                goto repeat;
        }
        if (chld_pid) {
@@ -522,14 +558,13 @@ repeat:
        }
        alarm(ALARM_TIMEOUT);
        close_listed_fds();
-       close(sockfd); /* child doesn't need the listener */
+       para_signal_shutdown();
        /*
         * put info on who we are serving into argv[0] to make
         * client ip visible in top/ps
         */
        for (i = argc - 1; i >= 0; i--)
                memset(argv[i], 0, strlen(argv[i]));
-       sprintf(argv[0], "para_server (serving %s)",
-               inet_ntoa(their_addr.sin_addr));
-       return handle_connect(new_fd, &their_addr);
+       sprintf(argv[0], "para_server (serving %s)", peer_name);
+       return handle_connect(new_fd, peer_name);
 }