wma: Decode as much as possible.
[paraslash.git] / afs.c
diff --git a/afs.c b/afs.c
index d7c1ecfded5adf25c0a9c81ed86667c614d4f66e..1350db3423c3a184cb645e09cae9a2ebb060358b 100644 (file)
--- a/afs.c
+++ b/afs.c
@@ -1,16 +1,21 @@
 /*
- * Copyright (C) 2007-2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2007-2009 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
 /** \file afs.c Paraslash's audio file selector. */
 
+#include <regex.h>
 #include <signal.h>
 #include <fnmatch.h>
+#include <openssl/rc4.h>
+#include <osl.h>
+
 #include "server.cmdline.h"
 #include "para.h"
 #include "error.h"
+#include "crypt.h"
 #include "string.h"
 #include "afh.h"
 #include "afs.h"
@@ -24,6 +29,7 @@
 #include "sched.h"
 #include "signal.h"
 #include "fd.h"
+#include "mood.h"
 
 /** The osl tables used by afs. \sa blob.c. */
 enum afs_table_num {
@@ -54,13 +60,13 @@ enum afs_table_num {
 };
 
 static struct afs_table afs_tables[NUM_AFS_TABLES] = {
-       [TBLNUM_AUDIO_FILES] = {.init = aft_init},
-       [TBLNUM_ATTRIBUTES] = {.init = attribute_init},
-       [TBLNUM_SCORES] = {.init = score_init},
-       [TBLNUM_MOODS] = {.init = moods_init},
-       [TBLNUM_LYRICS] = {.init = lyrics_init},
-       [TBLNUM_IMAGES] = {.init = images_init},
-       [TBLNUM_PLAYLIST] = {.init = playlists_init},
+       [TBLNUM_AUDIO_FILES] = {.init = aft_init, .name = "audio_files"},
+       [TBLNUM_ATTRIBUTES] = {.init = attribute_init, .name = "attributes"},
+       [TBLNUM_SCORES] = {.init = score_init, .name = "scores"},
+       [TBLNUM_MOODS] = {.init = moods_init, .name = "moods"},
+       [TBLNUM_LYRICS] = {.init = lyrics_init, .name = "lyrics"},
+       [TBLNUM_IMAGES] = {.init = images_init, .name = "images"},
+       [TBLNUM_PLAYLIST] = {.init = playlists_init, .name = "playlists"},
 };
 
 struct command_task {
@@ -75,6 +81,7 @@ struct command_task {
        struct task task;
 };
 
+extern int mmd_mutex;
 extern struct misc_meta_data *mmd;
 
 static int server_socket;
@@ -84,7 +91,6 @@ static struct signal_task signal_task_struct;
 static enum play_mode current_play_mode;
 static char *current_mop; /* mode or playlist specifier. NULL means dummy mooe */
 
-
 /**
  * A random number used to "authenticate" the connection.
  *
@@ -140,6 +146,36 @@ struct callback_result {
        size_t result_size;
 };
 
+static int dispatch_result(int result_shmid, callback_result_handler *handler,
+               void *private_result_data)
+{
+       struct osl_object result;
+       void *result_shm;
+       int ret2, ret = shm_attach(result_shmid, ATTACH_RO, &result_shm);
+       struct callback_result *cr = result_shm;
+
+       if (ret < 0) {
+               PARA_ERROR_LOG("attach failed: %s\n", para_strerror(-ret));
+               return ret;
+       }
+       result.size = cr->result_size;
+       result.data = result_shm + sizeof(*cr);
+       if (result.size) {
+               assert(handler);
+               ret = handler(&result, private_result_data);
+               if (ret < 0)
+                       PARA_NOTICE_LOG("result handler error: %s\n",
+                               para_strerror(-ret));
+       }
+       ret2 = shm_detach(result_shm);
+       if (ret2 < 0) {
+               PARA_ERROR_LOG("detach failed: %s\n", para_strerror(-ret2));
+               if (ret >= 0)
+                       ret = ret2;
+       }
+       return ret;
+}
+
 /**
  * Ask the afs process to call a given function.
  *
@@ -160,8 +196,7 @@ struct callback_result {
  * shmid are passed to that function as an osl object. The private_result_data
  * pointer is passed as the second argument to \a result_handler.
  *
- * \return Negative, on errors, the return value of the callback function
- * otherwise.
+ * \return Standard.
  *
  * \sa send_option_arg_callback_request(), send_standard_callback_request().
  */
@@ -170,10 +205,11 @@ int send_callback_request(callback_function *f, struct osl_object *query,
                void *private_result_data)
 {
        struct callback_query *cq;
-       int num_results = 0, ret, fd = -1, query_shmid, result_shmid;
-       void *query_shm, *result_shm;
+       int ret, fd = -1, query_shmid, result_shmid;
+       void *query_shm;
        char buf[sizeof(afs_socket_cookie) + sizeof(int)];
        size_t query_shm_size = sizeof(*cq);
+       int dispatch_error = 0;
 
        if (query)
                query_shm_size += query->size;
@@ -204,45 +240,37 @@ int send_callback_request(callback_function *f, struct osl_object *query,
        ret = send_bin_buffer(fd, buf, sizeof(buf));
        if (ret < 0)
                goto out;
+       /*
+        * Read all shmids from afs.
+        *
+        * Even if the dispatcher returns an error we _must_ continue to read
+        * shmids from fd so that we can destroy all shared memory areas that
+        * have been created for us by the afs process.
+        */
        for (;;) {
                ret = recv_bin_buffer(fd, buf, sizeof(int));
                if (ret <= 0)
                        goto out;
-               if (ret != sizeof(int)) {
-                       ret = -E_AFS_SHORT_READ;
-                       goto out;
-               }
+               assert(ret == sizeof(int));
                ret = *(int *) buf;
-               if (ret <= 0)
-                       goto out;
+               assert(ret > 0);
                result_shmid = ret;
-               ret = shm_attach(result_shmid, ATTACH_RO, &result_shm);
-               if (ret >= 0) {
-                       struct callback_result *cr = result_shm;
-                       struct osl_object result;
-                       num_results++;
-                       result.size = cr->result_size;
-                       result.data = result_shm + sizeof(*cr);
-                       if (result.size) {
-                               assert(result_handler);
-                               ret = result_handler(&result, private_result_data);
-                               if (shm_detach(result_shm) < 0)
-                                       PARA_ERROR_LOG("can not detach result\n");
-                       }
-               } else
-                       PARA_ERROR_LOG("attach result failed: %d\n", ret);
-               if (shm_destroy(result_shmid) < 0)
-                       PARA_ERROR_LOG("destroy result failed\n");
+               if (!dispatch_error) {
+                       ret = dispatch_result(result_shmid, result_handler,
+                               private_result_data);
+                       if (ret < 0)
+                               dispatch_error = 1;
+               }
+               ret = shm_destroy(result_shmid);
                if (ret < 0)
-                       break;
+                       PARA_CRIT_LOG("destroy result failed: %s\n",
+                               para_strerror(-ret));
        }
 out:
        if (shm_destroy(query_shmid) < 0)
-               PARA_ERROR_LOG("%s\n", "shm destroy error");
+               PARA_CRIT_LOG("shm destroy error\n");
        if (fd >= 0)
                close(fd);
-       if (ret >= 0)
-               ret = num_results;
 //     PARA_DEBUG_LOG("callback_ret: %d\n", ret);
        return ret;
 }
@@ -319,7 +347,7 @@ static int action_if_pattern_matches(struct osl_row *row, void *data)
        struct pattern_match_data *pmd = data;
        struct osl_object name_obj;
        const char *p, *name;
-       int ret = osl_get_object(pmd->table, row, pmd->match_col_num, &name_obj);
+       int ret = osl(osl_get_object(pmd->table, row, pmd->match_col_num, &name_obj));
        const char *pattern_txt = (const char *)pmd->patterns.data;
 
        if (ret < 0)
@@ -346,16 +374,15 @@ static int action_if_pattern_matches(struct osl_row *row, void *data)
  *
  * \param pmd Describes what to match and how.
  *
- * \return The return value of the underlying call to osl_rbtree_loop()
- * or osl_rbtree_loop_reverse().
+ * \return Standard.
  */
 int for_each_matching_row(struct pattern_match_data *pmd)
 {
        if (pmd->pm_flags & PM_REVERSE_LOOP)
-               return osl_rbtree_loop_reverse(pmd->table, pmd->loop_col_num, pmd,
-                       action_if_pattern_matches);
-       return osl_rbtree_loop(pmd->table, pmd->loop_col_num, pmd,
-                       action_if_pattern_matches);
+               return osl(osl_rbtree_loop_reverse(pmd->table, pmd->loop_col_num, pmd,
+                       action_if_pattern_matches));
+       return osl(osl_rbtree_loop(pmd->table, pmd->loop_col_num, pmd,
+                       action_if_pattern_matches));
 }
 
 /**
@@ -380,80 +407,6 @@ int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
        return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
 }
 
-/*
- * write input from fd to dynamically allocated buffer,
- * but maximal max_size byte.
- */
-static int fd2buf(int fd, unsigned max_size, struct osl_object *obj)
-{
-       const size_t chunk_size = 1024;
-       size_t size = 2048, received = 0;
-       int ret;
-       char *buf = para_malloc(size);
-
-       for (;;) {
-               ret = recv_bin_buffer(fd, buf + received, chunk_size);
-               if (ret <= 0)
-                       break;
-               received += ret;
-               if (received + chunk_size >= size) {
-                       size *= 2;
-                       ret = -E_INPUT_TOO_LARGE;
-                       if (size > max_size)
-                               break;
-                       buf = para_realloc(buf, size);
-               }
-       }
-       obj->data = buf;
-       obj->size = received;
-       if (ret < 0)
-               free(buf);
-       return ret;
-}
-
-/**
- * Read data from a file descriptor, and send it to the afs process.
- *
- * \param fd File descriptor to read data from.
- * \param arg_obj Pointer to the arguments to \a f.
- * \param f The callback function.
- * \param max_len Don't read more than that many bytes from stdin.
- * \param result_handler See \ref send_callback_request.
- * \param private_result_data See \ref send_callback_request.
- *
- * This function is used by commands that wish to let para_server store
- * arbitrary data specified by the user (for instance the add_blob family of
- * commands). First, at most \a max_len bytes are read from \a fd, the result
- * is concatenated with the buffer given by \a arg_obj, and the combined buffer
- * is made available to the afs process via the callback method. See \ref
- * send_callback_request for details.
- *
- * \return Negative on errors, the return value of the underlying call to
- * send_callback_request() otherwise.
- */
-int stdin_command(int fd, struct osl_object *arg_obj, callback_function *f,
-               unsigned max_len, callback_result_handler *result_handler,
-               void *private_result_data)
-{
-       struct osl_object query, stdin_obj;
-       int ret;
-
-       ret = send_buffer(fd, AWAITING_DATA_MSG);
-       if (ret < 0)
-               return ret;
-       ret = fd2buf(fd, max_len, &stdin_obj);
-       if (ret < 0)
-               return ret;
-       query.size = arg_obj->size + stdin_obj.size;
-       query.data = para_malloc(query.size);
-       memcpy(query.data, arg_obj->data, arg_obj->size);
-       memcpy((char *)query.data + arg_obj->size, stdin_obj.data, stdin_obj.size);
-       free(stdin_obj.data);
-       ret = send_callback_request(f, &query, result_handler, private_result_data);
-       free(query.data);
-       return ret;
-}
-
 static int pass_afd(int fd, char *buf, size_t size)
 {
        struct msghdr msg = {.msg_iov = NULL};
@@ -499,7 +452,7 @@ static int pass_afd(int fd, char *buf, size_t size)
  *
  * \sa open_and_update_audio_file().
  */
-int open_next_audio_file(void)
+static int open_next_audio_file(void)
 {
        struct osl_row *aft_row;
        struct audio_file_data afd;
@@ -571,15 +524,15 @@ static int activate_mood_or_playlist(char *arg, int *num_admissible)
                free(current_mop);
                if (arg) {
                        current_mop = para_strdup(arg);
-                       mmd_lock();
+                       mutex_lock(mmd_mutex);
                        strncpy(mmd->afs_mode_string, arg,
                                sizeof(mmd->afs_mode_string));
                        mmd->afs_mode_string[sizeof(mmd->afs_mode_string) - 1] = '\0';
-                       mmd_unlock();
+                       mutex_unlock(mmd_mutex);
                } else {
-                       mmd_lock();
+                       mutex_lock(mmd_mutex);
                        strcpy(mmd->afs_mode_string, "dummy");
-                       mmd_unlock();
+                       mutex_unlock(mmd_mutex);
                        current_mop = NULL;
                }
        }
@@ -629,21 +582,22 @@ out:
  * Result handler for sending data to the para_client process.
  *
  * \param result The data to be sent.
- * \param fd_ptr Pointer to the file descriptor.
+ * \param private Pointer to rc4 context.
  *
- * \return The return value of the underlying call to send_bin_buffer().
+ * \return The return value of the underlying call to rc4_send_bin_buffer().
  *
- * \sa \ref callback_result_handler.
+ * \sa \ref callback_result_handler, \ref rc4_send_bin_buffer().
  */
-int send_result(struct osl_object *result, void *fd_ptr)
+int rc4_send_result(struct osl_object *result, void *private)
 {
-       int fd = *(int *)fd_ptr;
+       struct rc4_context *rc4c = private;
+
        if (!result->size)
                return 1;
-       return send_bin_buffer(fd, result->data, result->size);
+       return rc4_send_bin_buffer(rc4c, result->data, result->size);
 }
 
-int com_select(int fd, int argc, char * const * const argv)
+int com_select(struct rc4_context *rc4c, int argc, char * const * const argv)
 {
        struct osl_object query;
 
@@ -652,7 +606,7 @@ int com_select(int fd, int argc, char * const * const argv)
        query.data = argv[1];
        query.size = strlen(argv[1]) + 1;
        return send_callback_request(com_select_callback, &query,
-               &send_result, &fd);
+               &rc4_send_result, rc4c);
 }
 
 static void init_admissible_files(char *arg)
@@ -707,7 +661,7 @@ static void get_database_dir(void)
                else {
                        char *home = para_homedir();
                        database_dir = make_message(
-                               "%s/.paraslash/afs_database", home);
+                               "%s/.paraslash/afs_database-0.4", home);
                        free(home);
                }
        }
@@ -747,59 +701,50 @@ static int open_afs_tables(void)
        return ret;
 }
 
-static void unregister_tasks(void)
-{
-       unregister_task(&command_task_struct.task);
-       unregister_task(&signal_task_struct.task);
-}
-
 static void signal_pre_select(struct sched *s, struct task *t)
 {
-       struct signal_task *st = t->private_data;
-       t->ret = 1;
+       struct signal_task *st = container_of(t, struct signal_task, task);
        para_fd_set(st->fd, &s->rfds, &s->max_fileno);
 }
 
-static void signal_post_select(struct sched *s, struct task *t)
+static void afs_signal_post_select(struct sched *s, struct task *t)
 {
-       struct signal_task *st = t->private_data;
-       t->ret = -E_AFS_PARENT_DIED;
-       if (getppid() == 1)
-               goto err;
-       t->ret = 1;
+       struct signal_task *st = container_of(t, struct signal_task, task);
+       if (getppid() == 1) {
+               PARA_EMERG_LOG("para_server died\n");
+               goto shutdown;
+       }
        if (!FD_ISSET(st->fd, &s->rfds))
                return;
        st->signum = para_next_signal();
-       t->ret = 1;
-       if (st->signum == SIGUSR1)
-               return; /* ignore SIGUSR1 */
        if (st->signum == SIGHUP) {
                close_afs_tables();
-               t->ret = open_afs_tables();
-               if (t->ret < 0)
-                       goto err;
+               parse_config_or_die(1);
+               t->error = open_afs_tables();
+               if (t->error < 0)
+                       return;
                init_admissible_files(current_mop);
                return;
        }
-       t->ret = -E_AFS_SIGNAL;
-err:
-       PARA_NOTICE_LOG("%s\n", para_strerror(-t->ret));
-       unregister_tasks();
+       PARA_EMERG_LOG("terminating on signal %d\n", st->signum);
+shutdown:
+       sched_shutdown();
+       t->error = -E_AFS_SIGNAL;
 }
 
 static void register_signal_task(void)
 {
        struct signal_task *st = &signal_task_struct;
+
+       para_sigaction(SIGPIPE, SIG_IGN);
        st->fd = para_signal_init();
        PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
        para_install_sighandler(SIGINT);
        para_install_sighandler(SIGTERM);
-       para_install_sighandler(SIGPIPE);
        para_install_sighandler(SIGHUP);
 
        st->task.pre_select = signal_pre_select;
-       st->task.post_select = signal_post_select;
-       st->task.private_data = st;
+       st->task.post_select = afs_signal_post_select;
        sprintf(st->task.status, "signal task");
        register_task(&st->task);
 }
@@ -818,14 +763,13 @@ struct afs_client {
 
 static void command_pre_select(struct sched *s, struct task *t)
 {
-       struct command_task *ct = t->private_data;
+       struct command_task *ct = container_of(t, struct command_task, task);
        struct afs_client *client;
 
        para_fd_set(server_socket, &s->rfds, &s->max_fileno);
        para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
        list_for_each_entry(client, &afs_client_list, node)
                para_fd_set(client->fd, &s->rfds, &s->max_fileno);
-       t->ret = 1;
 }
 
 /**
@@ -895,31 +839,27 @@ static int call_callback(int fd, int query_shmid)
        query.data = (char *)query_shm + sizeof(*cq);
        query.size = cq->query_size;
        cq->handler(fd, &query);
-       return 1;
+       return shm_detach(query_shm);
 }
 
-static void execute_server_command(void)
+static int execute_server_command(void)
 {
        char buf[8];
        int ret = recv_bin_buffer(server_socket, buf, sizeof(buf) - 1);
 
        if (ret <= 0) {
-               if (ret < 0)
-                       PARA_ERROR_LOG("%s\n", para_strerror(-ret));
-               return;
+               if (!ret)
+                       ret = -ERRNO_TO_PARA_ERROR(ECONNRESET);
+               goto err;
        }
        buf[ret] = '\0';
        PARA_DEBUG_LOG("received: %s\n", buf);
-       if (!strcmp(buf, "new")) {
-               ret = open_next_audio_file();
-               if (ret < 0) {
-                       PARA_EMERG_LOG("%s\n", para_strerror(-ret));
-                       unregister_tasks();
-               }
-               return;
-       }
-       PARA_ERROR_LOG("unknown command\n");
-
+       ret = -E_BAD_CMD;
+       if (strcmp(buf, "new"))
+               goto err;
+       ret = open_next_audio_file();
+err:
+       return ret;
 }
 
 static void execute_afs_command(int fd, uint32_t expected_cookie)
@@ -960,12 +900,19 @@ err:
 
 static void command_post_select(struct sched *s, struct task *t)
 {
-       struct command_task *ct = t->private_data;
+       struct command_task *ct = container_of(t, struct command_task, task);
        struct sockaddr_un unix_addr;
        struct afs_client *client, *tmp;
-       int fd;
-       if (FD_ISSET(server_socket, &s->rfds))
-               execute_server_command();
+       int fd, ret;
+
+       if (FD_ISSET(server_socket, &s->rfds)) {
+               ret = execute_server_command();
+               if (ret < 0) {
+                       PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+                       sched_shutdown();
+                       return;
+               }
+       }
 
        /* Check the list of connected clients. */
        list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
@@ -984,25 +931,23 @@ static void command_post_select(struct sched *s, struct task *t)
        }
        /* Accept connections on the local socket. */
        if (!FD_ISSET(ct->fd, &s->rfds))
-               goto out;
-       t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
-       if (t->ret < 0) {
-               PARA_NOTICE_LOG("%s\n", para_strerror(-t->ret));
-               goto out;
+               return;
+       ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
+       if (ret < 0) {
+               PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
+               return;
        }
-       fd = t->ret;
-       t->ret = mark_fd_nonblocking(fd);
-       if (t->ret < 0) {
-               PARA_NOTICE_LOG("%s\n", para_strerror(-t->ret));
+       fd = ret;
+       ret = mark_fd_nonblocking(fd);
+       if (ret < 0) {
+               PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
                close(fd);
-               goto out;
+               return;
        }
        client = para_malloc(sizeof(*client));
        client->fd = fd;
        client->connect_time = *now;
        para_list_add(&client->node, &afs_client_list);
-out:
-       t->ret = 1;
 }
 
 static void register_command_task(uint32_t cookie)
@@ -1013,17 +958,10 @@ static void register_command_task(uint32_t cookie)
 
        ct->task.pre_select = command_pre_select;
        ct->task.post_select = command_post_select;
-       ct->task.private_data = ct;
        sprintf(ct->task.status, "command task");
        register_task(&ct->task);
 }
 
-static void register_tasks(uint32_t cookie)
-{
-       register_signal_task();
-       register_command_task(cookie);
-}
-
 /**
  * Initialize the audio file selector process.
  *
@@ -1032,32 +970,32 @@ static void register_tasks(uint32_t cookie)
  */
 __noreturn void afs_init(uint32_t cookie, int socket_fd)
 {
-       struct sched s;
+       static struct sched s;
        int i, ret;
 
+       register_signal_task();
        INIT_LIST_HEAD(&afs_client_list);
        for (i = 0; i < NUM_AFS_TABLES; i++)
                afs_tables[i].init(&afs_tables[i]);
        ret = open_afs_tables();
-
-       if (ret < 0) {
-               PARA_EMERG_LOG("%s\n", para_strerror(-ret));
-               exit(EXIT_FAILURE);
-       }
+       if (ret < 0)
+               goto out;
        server_socket = socket_fd;
        ret = mark_fd_nonblocking(server_socket);
        if (ret < 0)
-               exit(EXIT_FAILURE);
+               goto out_close;
        PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
                server_socket, (unsigned) cookie);
        init_admissible_files(conf.afs_initial_mode_arg);
-       register_tasks(cookie);
+       register_command_task(cookie);
        s.default_timeout.tv_sec = 0;
        s.default_timeout.tv_usec = 999 * 1000;
        ret = schedule(&s);
+out_close:
+       close_afs_tables();
+out:
        if (ret < 0)
                PARA_EMERG_LOG("%s\n", para_strerror(-ret));
-       close_afs_tables();
        exit(EXIT_FAILURE);
 }
 
@@ -1065,7 +1003,7 @@ static void create_tables_callback(int fd, const struct osl_object *query)
 {
        uint32_t table_mask = *(uint32_t *)query->data;
        int i, ret;
-       char *buf;
+       struct para_buffer pb = {.buf = NULL};
 
        close_afs_tables();
        for (i = 0; i < NUM_AFS_TABLES; i++) {
@@ -1078,18 +1016,18 @@ static void create_tables_callback(int fd, const struct osl_object *query)
                ret = t->create(database_dir);
                if (ret < 0)
                        goto out;
+               para_printf(&pb, "successfully created %s table\n", t->name);
        }
        ret = open_afs_tables();
 out:
-       if (ret >= 0)
-               buf = make_message("successfully created afs table(s)\n");
-       else
-               buf = make_message("%s\n", para_strerror(-ret));
-       pass_buffer_as_shm(buf, strlen(buf), &fd);
-       free(buf);
+       if (ret < 0)
+               para_printf(&pb, "%s\n", para_strerror(-ret));
+       if (pb.buf)
+               pass_buffer_as_shm(pb.buf, pb.offset, &fd);
+       free(pb.buf);
 }
 
-int com_init(int fd, int argc, char * const * const argv)
+int com_init(struct rc4_context *rc4c, int argc, char * const * const argv)
 {
        int i, j, ret;
        uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
@@ -1114,9 +1052,10 @@ int com_init(int fd, int argc, char * const * const argv)
                                return -E_BAD_TABLE_NAME;
                }
        }
-       ret = send_callback_request(create_tables_callback, &query, NULL, NULL);
+       ret = send_callback_request(create_tables_callback, &query,
+               rc4_send_result, rc4c);
        if (ret < 0)
-               return send_va_buffer(fd, "%s\n", para_strerror(-ret));
+               return rc4_send_va_buffer(rc4c, "%s\n", para_strerror(-ret));
        return ret;
 }
 
@@ -1134,7 +1073,7 @@ enum com_check_flags {
        CHECK_PLAYLISTS = 4
 };
 
-int com_check(int fd, int argc, char * const * const argv)
+int com_check(struct rc4_context *rc4c, int argc, char * const * const argv)
 {
        unsigned flags = 0;
        int i, ret;
@@ -1166,23 +1105,36 @@ int com_check(int fd, int argc, char * const * const argv)
        if (!flags)
                flags = ~0U;
        if (flags & CHECK_AFT) {
-               ret = send_callback_request(aft_check_callback, NULL, send_result, &fd);
+               ret = send_callback_request(aft_check_callback, NULL,
+                       rc4_send_result, rc4c);
                if (ret < 0)
                        return ret;
        }
        if (flags & CHECK_PLAYLISTS) {
-               ret = send_callback_request(playlist_check_callback, NULL, send_result, &fd);
+               ret = send_callback_request(playlist_check_callback,
+                       NULL, rc4_send_result, rc4c);
                if (ret < 0)
                        return ret;
        }
        if (flags & CHECK_MOODS) {
-               ret = send_callback_request(mood_check_callback, NULL, send_result, &fd);
+               ret = send_callback_request(mood_check_callback, NULL,
+                       rc4_send_result, rc4c);
                if (ret < 0)
                        return ret;
        }
        return 1;
 }
 
+/**
+ * The afs event dispatcher.
+ *
+ * \param event Type of the event.
+ * \param pb May be \p NULL.
+ * \param data Type depends on \a event.
+ *
+ * This function calls the table handlers of all tables and passes \a pb and \a
+ * data verbatim. It's up to the handlers to interpret the \a data pointer.
+ */
 void afs_event(enum afs_events event, struct para_buffer *pb,
                void *data)
 {
@@ -1194,7 +1146,8 @@ void afs_event(enum afs_events event, struct para_buffer *pb,
                        continue;
                ret = t->event_handler(event, pb, data);
                if (ret < 0)
-                       PARA_CRIT_LOG("%s\n", para_strerror(-ret));
+                       PARA_CRIT_LOG("table %s, event %d: %s\n", t->name,
+                               event, para_strerror(-ret));
        }
 }