README: Kill "obligatory" and "optional" tags.
[paraslash.git] / server.c
index 7e52fa5e12a2d929a1ef8e390ff31e5dcb7e6b64..febfe2ad02ca2828c1dffe65d2243ed8b661e605 100644 (file)
--- a/server.c
+++ b/server.c
@@ -1,47 +1,88 @@
 /*
  * Copyright (C) 1997-2007 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:
  *
- *  Good starting points for reading are probably \ref audio_file_selector,
- *  \ref sender, \ref receiver, \ref receiver_node, \ref filter, \ref
- *  filter_node.
+ *     - 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.
+ *
+ * Low-level data structures:
+ *
+ *     - 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 "afh.h"
+#include "string.h"
 #include "afs.h"
 #include "server.h"
 #include "vss.h"
 #include "config.h"
 #include "close_on_fork.h"
 #include "send.h"
-#include "error.h"
 #include "net.h"
 #include "daemon.h"
-#include "string.h"
 #include "ipc.h"
 #include "fd.h"
+#include "list.h"
+#include "sched.h"
 #include "signal.h"
 #include "user_list.h"
 
@@ -52,16 +93,16 @@ INIT_SERVER_ERRLISTS;
 #define ALARM_TIMEOUT 10
 
 /**
- * pointer to shared memory area for communication between para_server
- * and its children. exported to vss.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
  *
- * It also contains the options for all audio file selectors, audio format handler
- * 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;
 
@@ -72,35 +113,6 @@ 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[] = {
        {
@@ -182,14 +194,12 @@ 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;
+       strcpy(mmd->afd.path, "(none)");
        mmd->vss_status_flags = VSS_NEXT;
        mmd->new_vss_status_flags = VSS_NEXT;
        mmd->sender_cmd_data.cmd_num = -1;
@@ -202,7 +212,7 @@ err_out:
 /**
  * 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)
 {
@@ -228,7 +238,7 @@ 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_file);
@@ -244,7 +254,13 @@ 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 */
@@ -271,7 +287,8 @@ static void setup_signal_handling(void)
        int ret = 0;
 
        signal_pipe = para_signal_init();
-       PARA_NOTICE_LOG("%s", "setting up signal handlers\n");
+
+       PARA_NOTICE_LOG("setting up signal handlers\n");
        ret += para_install_sighandler(SIGINT);
        ret += para_install_sighandler(SIGTERM);
        ret += para_install_sighandler(SIGHUP);
@@ -282,32 +299,7 @@ static void setup_signal_handling(void)
                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 */
+       add_close_on_fork_list(signal_pipe);
 }
 
 static unsigned init_network(void)
@@ -320,6 +312,7 @@ static unsigned init_network(void)
        ret = mark_fd_nonblock(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));
@@ -328,8 +321,9 @@ err:
 
 static void init_random_seed(void)
 {
-       int fd, ret = -1, len = sizeof(unsigned int);
+       int fd, ret = -1;
        unsigned int seed;
+       size_t len = sizeof(unsigned int);
 
        fd = open("/dev/urandom", O_RDONLY);
        if (fd < 0)
@@ -349,7 +343,37 @@ out:
        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_nonblock(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;
@@ -368,37 +392,22 @@ static unsigned do_inits(int argc, char **argv)
        /* become daemon */
        if (conf.daemon_given)
                daemon_init();
-       init_selector();
-//     PARA_ERROR_LOG("num: %d\n", mmd->selector_num);
-       PARA_NOTICE_LOG("%s", "initializing virtual streaming system\n");
+       PARA_NOTICE_LOG("initializing audio format handlers\n");
+       afh_init();
+       PARA_NOTICE_LOG("initializing virtual streaming system\n");
        vss_init();
        mmd->server_pid = getpid();
        setup_signal_handling();
+       PARA_NOTICE_LOG("initializing the audio file selector\n");
+       init_afs();
        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.
  */
@@ -408,9 +417,9 @@ static void handle_sighup(void)
        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)
@@ -430,8 +439,8 @@ out:
        prev_events = mmd->events;
        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);
        }
 }
@@ -456,7 +465,7 @@ int main(int argc, char *argv[])
        struct timeval *timeout;
 
        valid_fd_012();
-       sockfd = do_inits(argc, argv);
+       sockfd = server_init(argc, argv);
 repeat:
        FD_ZERO(&rfds);
        FD_ZERO(&wfds);
@@ -464,26 +473,19 @@ 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 = vss_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++) {
@@ -497,23 +499,33 @@ repeat:
        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);
                }
        }
@@ -548,7 +560,7 @@ 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