2 * Copyright (C) 2007 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file afs.c Paraslash's audio file selector. */
9 #include "server.cmdline.h"
14 #include <dirent.h> /* readdir() */
26 /** The osl tables used by afs. \sa blob.c. */
28 /** Contains audio file information. See aft.c. */
30 /** The table for the paraslash attributes. See attribute.c. */
33 * Paraslash's scoring system is based on Gaussian normal
34 * distributions, and the relevant data is stored in the rbtrees of an
35 * osl table containing only volatile columns. See score.c for
40 * A standard blob table containing the mood definitions. For details
44 /** A blob table containing lyrics on a per-song basis. */
46 /** Another blob table for images (for example album cover art). */
48 /** Yet another blob table for storing standard playlists. */
50 /** How many tables are in use? */
54 static struct table_info afs_tables
[NUM_AFS_TABLES
];
57 /** The file descriptor for the local socket. */
60 * Value sent by the command handlers to identify themselves as
61 * children of the running para_server.
64 /** The associated task structure. */
69 * A random number used to "authenticate" the connection.
71 * para_server picks this number by random before forking the afs process. The
72 * command handlers write this number together with the id of the shared memory
73 * area containing the query. This way, a malicious local user has to know this
74 * number to be able to cause the afs process to crash by sending fake queries.
76 extern uint32_t afs_socket_cookie
;
79 * Struct to let command handlers execute a callback in afs context.
81 * Commands that need to change the state of afs can't change the relevant data
82 * structures directly because commands are executed in a child process, i.e.
83 * they get their own virtual address space.
85 * This structure is used by \p send_callback_request() (executed from handler
86 * context) in order to let the afs process call the specified function. An
87 * instance of that structure is written to a shared memory area together with
88 * the arguments to the callback function. The identifier of the shared memory
89 * area is written to the command socket.
91 * The afs process accepts connections on the command socket and reads the
92 * shared memory id, attaches the corresponing area, calls the given handler to
93 * perform the desired action and to optionally compute a result.
95 * The result and a \p callback_result structure is then written to another
96 * shared memory area. The identifier for that area is written to the handler's
97 * command socket, so that the handler process can read the id, attach the
98 * shared memory area and use the result.
100 * \sa struct callback_result.
102 struct callback_query
{
103 /** The function to be called. */
104 callback_function
*handler
;
105 /** The number of bytes of the query */
110 * Structure embedded in the result of a callback.
112 * If the callback produced a result, an instance of that structure is embeeded
113 * into the shared memory area holding the result, mainly to let the command
114 * handler know the size of the result.
116 * \sa struct callback_query.
118 struct callback_result
{
119 /** The number of bytes of the result. */
124 * Ask the parent process to call a given function.
126 * \param f The function to be called.
127 * \param query Pointer to arbitrary data for the callback.
128 * \param result Callback result will be stored here.
130 * This function creates a shared memory area, copies the buffer pointed to by
131 * \a buf to that area and notifies the afs process that \a f should be
134 * \return Negative, on errors, the return value of the callback function
137 * \sa send_option_arg_callback_request(), send_standard_callback_request().
139 int send_callback_request(callback_function
*f
, struct osl_object
*query
,
140 struct osl_object
*result
)
142 struct callback_query
*cq
;
143 struct callback_result
*cr
;
144 int ret
, fd
= -1, query_shmid
, result_shmid
;
145 void *query_shm
, *result_shm
;
146 char buf
[sizeof(afs_socket_cookie
) + sizeof(int)];
147 struct sockaddr_un unix_addr
;
148 size_t query_shm_size
= sizeof(*cq
);
151 query_shm_size
+= query
->size
;
152 ret
= shm_new(query_shm_size
);
156 ret
= shm_attach(query_shmid
, ATTACH_RW
, &query_shm
);
161 cq
->query_size
= query_shm_size
- sizeof(*cq
);
164 memcpy(query_shm
+ sizeof(*cq
), query
->data
, query
->size
);
165 ret
= shm_detach(query_shm
);
169 *(uint32_t *) buf
= afs_socket_cookie
;
170 *(int *) (buf
+ sizeof(afs_socket_cookie
)) = query_shmid
;
172 ret
= get_stream_socket(PF_UNIX
);
176 ret
= init_unix_addr(&unix_addr
, conf
.afs_socket_arg
);
179 ret
= PARA_CONNECT(fd
, &unix_addr
);
182 ret
= send_bin_buffer(fd
, buf
, sizeof(buf
));
185 ret
= recv_bin_buffer(fd
, buf
, sizeof(buf
));
188 if (ret
!= sizeof(int)) {
196 ret
= shm_attach(result_shmid
, ATTACH_RO
, &result_shm
);
200 result
->size
= cr
->result_size
;
201 result
->data
= para_malloc(result
->size
);
202 memcpy(result
->data
, result_shm
+ sizeof(*cr
), result
->size
);
203 ret
= shm_detach(result_shm
);
205 PARA_ERROR_LOG("can not detach result\n");
207 PARA_ERROR_LOG("attach result failed: %d\n", ret
);
208 if (shm_destroy(result_shmid
) < 0)
209 PARA_ERROR_LOG("destroy result failed\n");
212 if (shm_destroy(query_shmid
) < 0)
213 PARA_ERROR_LOG("%s\n", "shm destroy error");
216 // PARA_DEBUG_LOG("callback_ret: %d\n", ret);
221 * Send a callback request passing an options structure and an argument vector.
223 * \param options pointer to an arbitrary data structure.
224 * \param argc Argument count.
225 * \param argv Standard argument vector.
226 * \param f The callback function.
227 * \param result The result of the query is stored here.
229 * Some commands have a couple of options that are parsed in child context for
230 * syntactic correctness and are stored in a special options structure for that
231 * command. This function allows to pass such a structure together with a list
232 * of further arguments (often a list of audio files) to the parent process.
234 * \sa send_standard_callback_request(), send_callback_request().
236 int send_option_arg_callback_request(struct osl_object
*options
,
237 int argc
, char * const * const argv
, callback_function
*f
,
238 struct osl_object
*result
)
242 struct osl_object query
= {.size
= options
? options
->size
: 0};
244 for (i
= 0; i
< argc
; i
++)
245 query
.size
+= strlen(argv
[i
]) + 1;
246 query
.data
= para_malloc(query
.size
);
249 memcpy(query
.data
, options
->data
, options
->size
);
252 for (i
= 0; i
< argc
; i
++) {
253 strcpy(p
, argv
[i
]); /* OK */
254 p
+= strlen(argv
[i
]) + 1;
256 ret
= send_callback_request(f
, &query
, result
);
262 * Send a callback request with an argument vector only.
264 * \param argc The same meaning as in send_option_arg_callback_request().
265 * \param argv The same meaning as in send_option_arg_callback_request().
266 * \param f The same meaning as in send_option_arg_callback_request().
267 * \param result The same meaning as in send_option_arg_callback_request().
269 * This is similar to send_option_arg_callback_request(), but no options buffer
270 * is passed to the parent process.
272 * \return The return value of the underlying call to
273 * send_option_arg_callback_request().
275 int send_standard_callback_request(int argc
, char * const * const argv
,
276 callback_function
*f
, struct osl_object
*result
)
278 return send_option_arg_callback_request(NULL
, argc
, argv
, f
, result
);
282 * Compare two osl objects of string type.
284 * \param obj1 Pointer to the first object.
285 * \param obj2 Pointer to the second object.
287 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
288 * are taken into account.
290 * \return It returns an integer less than, equal to, or greater than zero if
291 * \a obj1 is found, respectively, to be less than, to match, or be greater than
294 * \sa strcmp(3), strncmp(3), osl_compare_func.
296 int string_compare(const struct osl_object
*obj1
, const struct osl_object
*obj2
)
298 const char *str1
= (const char *)obj1
->data
;
299 const char *str2
= (const char *)obj2
->data
;
300 return strncmp(str1
, str2
, PARA_MIN(obj1
->size
, obj2
->size
));
304 * A wrapper for strtol(3).
306 * \param str The string to be converted to a long integer.
307 * \param result The converted value is stored here.
309 * \return Positive on success, -E_ATOL on errors.
311 * \sa strtol(3), atoi(3).
313 int para_atol(const char *str
, long *result
)
319 errno
= 0; /* To distinguish success/failure after call */
320 val
= strtol(str
, &endptr
, base
);
322 if (errno
== ERANGE
&& (val
== LONG_MAX
|| val
== LONG_MIN
))
323 goto out
; /* overflow */
324 if (errno
!= 0 && val
== 0)
325 goto out
; /* other error */
327 goto out
; /* No digits were found */
329 goto out
; /* Further characters after number */
338 * write input from fd to dynamically allocated buffer,
339 * but maximal max_size byte.
341 static int fd2buf(int fd
, unsigned max_size
, struct osl_object
*obj
)
343 const size_t chunk_size
= 1024;
344 size_t size
= 2048, received
= 0;
346 char *buf
= para_malloc(size
);
349 ret
= recv_bin_buffer(fd
, buf
+ received
, chunk_size
);
353 if (received
+ chunk_size
>= size
) {
355 ret
= -E_INPUT_TOO_LARGE
;
358 buf
= para_realloc(buf
, size
);
362 obj
->size
= received
;
369 * Read data from a file descriptor, and send it to the afs process.
371 * \param fd File descriptor to read data from.
372 * \param arg_obj Pointer to the arguments to \a f.
373 * \param f The callback function.
374 * \param max_len Don't read more than that many bytes from stdin.
375 * \param result The result of the query is stored here.
377 * This function is used by commands that wish to let para_server store
378 * arbitrary data specified by the user (for instance the add_blob family of
379 * commands). First, at most \a max_len bytes are read from \a fd, the result
380 * is concatenated with the buffer given by \a arg_obj, and the combined buffer
381 * is made available to the parent process via shared memory.
383 * \return Negative on errors, the return value of the underlying call to
384 * send_callback_request() otherwise.
386 int stdin_command(int fd
, struct osl_object
*arg_obj
, callback_function
*f
,
387 unsigned max_len
, struct osl_object
*result
)
389 struct osl_object query
, stdin_obj
;
392 ret
= send_buffer(fd
, AWAITING_DATA_MSG
);
395 ret
= fd2buf(fd
, max_len
, &stdin_obj
);
398 query
.size
= arg_obj
->size
+ stdin_obj
.size
;
399 query
.data
= para_malloc(query
.size
);
400 memcpy(query
.data
, arg_obj
->data
, arg_obj
->size
);
401 memcpy((char *)query
.data
+ arg_obj
->size
, stdin_obj
.data
, stdin_obj
.size
);
402 free(stdin_obj
.data
);
403 ret
= send_callback_request(f
, &query
, result
);
409 * Open the audio file with highest score.
411 * \param afd Audio file data is returned here.
413 * This stores all information for streaming the "best" audio file
414 * in the \a afd structure.
416 * \return Positive on success, negative on errors.
418 * \sa close_audio_file(), open_and_update_audio_file().
420 int open_next_audio_file(struct audio_file_data
*afd
)
422 struct osl_row
*aft_row
;
425 ret
= score_get_best(&aft_row
, &afd
->score
);
428 ret
= open_and_update_audio_file(aft_row
, afd
);
435 * Free all resources which were allocated by open_next_audio_file().
437 * \param afd The structure previously filled in by open_next_audio_file().
439 * \return The return value of the underlying call to para_munmap().
441 * \sa open_next_audio_file().
443 int close_audio_file(struct audio_file_data
*afd
)
445 free(afd
->afhi
.chunk_table
);
446 return para_munmap(afd
->map
.data
, afd
->map
.size
);
450 static void play_loop(enum play_mode current_play_mode
)
453 struct audio_file_data afd
;
455 afd
.current_play_mode
= current_play_mode
;
456 for (i
= 0; i
< 0; i
++) {
457 ret
= open_next_audio_file(&afd
);
459 PARA_ERROR_LOG("failed to open next audio file: %d\n", ret
);
462 PARA_NOTICE_LOG("next audio file: %s, score: %li\n", afd
.path
, afd
.score
);
464 close_audio_file(&afd
);
470 static enum play_mode
init_admissible_files(void)
473 char *given_mood
, *given_playlist
;
475 given_mood
= "mood_that_was_given_at_the_command_line";
476 given_playlist
= "given_playlist";
479 ret
= mood_open(given_mood
);
482 PARA_WARNING_LOG("ignoring playlist %s\n",
484 return PLAY_MODE_MOOD
;
487 if (given_playlist
) {
488 ret
= playlist_open(given_playlist
);
490 return PLAY_MODE_PLAYLIST
;
492 ret
= mood_open(NULL
); /* open first available mood */
494 return PLAY_MODE_MOOD
;
495 mood_open(""); /* open dummy mood, always successful */
496 return PLAY_MODE_MOOD
;
499 static int setup_command_socket_or_die(void)
502 char *socket_name
= conf
.afs_socket_arg
;
503 struct sockaddr_un unix_addr
;
506 ret
= create_local_socket(socket_name
, &unix_addr
,
507 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IWOTH
);
509 PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret
), socket_name
);
512 if (listen(ret
, 5) < 0) {
513 PARA_EMERG_LOG("%s", "can not listen on socket\n");
516 PARA_INFO_LOG("listening on command socket %s (fd %d)\n", socket_name
,
521 static int server_socket
;
522 static struct command_task command_task_struct
;
523 static struct signal_task signal_task_struct
;
525 static void unregister_tasks(void)
527 unregister_task(&command_task_struct
.task
);
528 unregister_task(&signal_task_struct
.task
);
531 static void close_afs_tables(enum osl_close_flags flags
)
533 PARA_NOTICE_LOG("closing afs_tables\n");
534 score_shutdown(flags
);
535 attribute_shutdown(flags
);
538 moods_shutdown(flags
);
539 playlists_shutdown(flags
);
540 lyrics_shutdown(flags
);
541 images_shutdown(flags
);
545 static void signal_pre_select(struct sched
*s
, struct task
*t
)
547 struct signal_task
*st
= t
->private_data
;
549 para_fd_set(st
->fd
, &s
->rfds
, &s
->max_fileno
);
552 static void signal_post_select(struct sched
*s
, struct task
*t
)
554 struct signal_task
*st
= t
->private_data
;
556 if (!FD_ISSET(st
->fd
, &s
->rfds
))
558 st
->signum
= para_next_signal();
559 PARA_NOTICE_LOG("caught signal %d\n", st
->signum
);
561 if (st
->signum
== SIGUSR1
)
562 return; /* ignore SIGUSR1 */
563 t
->ret
= -E_SIGNAL_CAUGHT
;
567 static void register_signal_task(void)
569 struct signal_task
*st
= &signal_task_struct
;
570 st
->fd
= para_signal_init();
571 PARA_INFO_LOG("signal pipe: fd %d\n", st
->fd
);
572 para_install_sighandler(SIGINT
);
573 para_install_sighandler(SIGTERM
);
574 para_install_sighandler(SIGPIPE
);
576 st
->task
.pre_select
= signal_pre_select
;
577 st
->task
.post_select
= signal_post_select
;
578 st
->task
.private_data
= st
;
579 sprintf(st
->task
.status
, "signal task");
580 register_task(&st
->task
);
583 static void command_pre_select(struct sched
*s
, struct task
*t
)
585 struct command_task
*ct
= t
->private_data
;
587 para_fd_set(ct
->fd
, &s
->rfds
, &s
->max_fileno
);
591 * On errors, negative value is written to fd.
592 * On success: If query produced a result, the result_shmid is written to fd.
593 * Otherwise, zero is written.
595 static int call_callback(int fd
, int query_shmid
)
597 void *query_shm
, *result_shm
;
598 struct callback_query
*cq
;
599 struct callback_result
*cr
;
600 struct osl_object query
, result
= {.data
= NULL
};
601 int result_shmid
= -1, ret
, ret2
;
603 ret
= shm_attach(query_shmid
, ATTACH_RW
, &query_shm
);
607 query
.data
= (char *)query_shm
+ sizeof(*cq
);
608 query
.size
= cq
->query_size
;
609 ret
= cq
->handler(&query
, &result
);
610 ret2
= shm_detach(query_shm
);
611 if (ret2
< 0 && ret
>= 0)
616 if (!result
.data
|| !result
.size
)
618 ret
= shm_new(result
.size
+ sizeof(struct callback_result
));
622 ret
= shm_attach(result_shmid
, ATTACH_RW
, &result_shm
);
626 cr
->result_size
= result
.size
;
627 memcpy(result_shm
+ sizeof(*cr
), result
.data
, result
.size
);
628 ret
= shm_detach(result_shm
);
634 ret2
= send_bin_buffer(fd
, (char *)&ret
, sizeof(int));
635 if (ret
< 0 || ret2
< 0) {
636 if (result_shmid
>= 0)
637 if (shm_destroy(result_shmid
) < 0)
638 PARA_ERROR_LOG("destroy result failed\n");
645 static void command_post_select(struct sched
*s
, struct task
*t
)
647 struct command_task
*ct
= t
->private_data
;
648 struct sockaddr_un unix_addr
;
649 char buf
[sizeof(uint32_t) + sizeof(int)];
654 if (!FD_ISSET(ct
->fd
, &s
->rfds
))
656 t
->ret
= para_accept(ct
->fd
, &unix_addr
, sizeof(unix_addr
));
660 * The following errors may be caused by a malicious local user. So do
661 * not return an error in this case as this would terminate para_afs
665 /* FIXME: This is easily dosable (peer doesn't send data) */
666 t
->ret
= recv_bin_buffer(fd
, buf
, sizeof(buf
));
668 PARA_NOTICE_LOG("%s (%d)\n", PARA_STRERROR(-t
->ret
), t
->ret
);
671 if (t
->ret
!= sizeof(buf
)) {
672 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
673 t
->ret
, (long unsigned) sizeof(buf
));
676 cookie
= *(uint32_t *)buf
;
677 if (cookie
!= ct
->cookie
) {
678 PARA_NOTICE_LOG("received invalid cookie(got %u, expected %u)\n",
679 (unsigned)cookie
, (unsigned)ct
->cookie
);
682 query_shmid
= *(int *)(buf
+ sizeof(cookie
));
683 if (query_shmid
< 0) {
684 PARA_WARNING_LOG("received invalid query shmid %d)\n",
688 /* Ignore return value: Errors might be ok here. */
689 call_callback(fd
, query_shmid
);
695 static void register_command_task(uint32_t cookie
)
697 struct command_task
*ct
= &command_task_struct
;
698 ct
->fd
= setup_command_socket_or_die();
701 ct
->task
.pre_select
= command_pre_select
;
702 ct
->task
.post_select
= command_post_select
;
703 ct
->task
.private_data
= ct
;
704 sprintf(ct
->task
.status
, "command task");
705 register_task(&ct
->task
);
708 void register_tasks(uint32_t cookie
)
710 register_signal_task();
711 register_command_task(cookie
);
714 static char *database_dir
;
716 static int make_database_dir(void)
721 if (conf
.afs_database_dir_given
)
722 database_dir
= para_strdup(conf
.afs_database_dir_arg
);
724 char *home
= para_homedir();
725 database_dir
= make_message(
726 "%s/.paraslash/afs_database", home
);
730 PARA_INFO_LOG("afs_database dir %s\n", database_dir
);
731 ret
= para_mkdir(database_dir
, 0777);
732 if (ret
>= 0 || ret
== -E_EXIST
)
739 static int open_afs_tables(void)
741 int ret
= make_database_dir();
745 ret
= attribute_init(&afs_tables
[TBLNUM_ATTRIBUTES
], database_dir
);
748 ret
= moods_init(&afs_tables
[TBLNUM_MOODS
], database_dir
);
750 goto moods_init_error
;
751 ret
= playlists_init(&afs_tables
[TBLNUM_PLAYLIST
], database_dir
);
753 goto playlists_init_error
;
754 ret
= lyrics_init(&afs_tables
[TBLNUM_LYRICS
], database_dir
);
756 goto lyrics_init_error
;
757 ret
= images_init(&afs_tables
[TBLNUM_IMAGES
], database_dir
);
759 goto images_init_error
;
760 ret
= score_init(&afs_tables
[TBLNUM_SCORES
], database_dir
);
762 goto score_init_error
;
763 ret
= aft_init(&afs_tables
[TBLNUM_AUDIO_FILES
], database_dir
);
769 score_shutdown(OSL_MARK_CLEAN
);
771 images_shutdown(OSL_MARK_CLEAN
);
773 lyrics_shutdown(OSL_MARK_CLEAN
);
775 playlists_shutdown(OSL_MARK_CLEAN
);
776 playlists_init_error
:
777 moods_shutdown(OSL_MARK_CLEAN
);
779 attribute_shutdown(OSL_MARK_CLEAN
);
783 __noreturn
int afs_init(uint32_t cookie
, int socket_fd
)
785 enum play_mode current_play_mode
;
787 int ret
= open_afs_tables();
790 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret
));
793 server_socket
= socket_fd
;
794 ret
= mark_fd_nonblock(server_socket
);
797 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
798 server_socket
, (unsigned) cookie
);
799 current_play_mode
= init_admissible_files();
800 register_tasks(cookie
);
801 s
.default_timeout
.tv_sec
= 0;
802 s
.default_timeout
.tv_usec
= 99 * 1000;
805 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret
));
806 close_afs_tables(OSL_MARK_CLEAN
);
810 static int create_tables_callback(const struct osl_object
*query
,
811 __a_unused
struct osl_object
*result
)
813 uint32_t table_mask
= *(uint32_t *)query
->data
;
816 close_afs_tables(OSL_MARK_CLEAN
);
817 for (i
= 0; i
< NUM_AFS_TABLES
; i
++) {
818 struct table_info
*ti
= afs_tables
+ i
;
820 if (ti
->flags
& TBLFLAG_SKIP_CREATE
)
822 if (!(table_mask
& (1 << i
)))
824 ret
= osl_create_table(ti
->desc
);
828 ret
= open_afs_tables();
829 return ret
< 0? ret
: 0;
832 int com_init(int fd
, int argc
, char * const * const argv
)
835 uint32_t table_mask
= (1 << (NUM_AFS_TABLES
+ 1)) - 1;
836 struct osl_object query
= {.data
= &table_mask
,
837 .size
= sizeof(table_mask
)};
841 for (i
= 1; i
< argc
; i
++) {
842 for (j
= 0; j
< NUM_AFS_TABLES
; j
++) {
843 struct table_info
*ti
= afs_tables
+ j
;
845 if (ti
->flags
& TBLFLAG_SKIP_CREATE
)
847 if (strcmp(argv
[i
], ti
->desc
->name
))
849 table_mask
|= (1 << j
);
852 if (j
== NUM_AFS_TABLES
)
853 return -E_BAD_TABLE_NAME
;
856 ret
= send_callback_request(create_tables_callback
, &query
, NULL
);
859 return send_va_buffer(fd
, "successfully created afs table(s)\n");
862 enum com_check_flags
{
868 int com_check(int fd
, int argc
, char * const * const argv
)
872 struct osl_object result
;
874 for (i
= 1; i
< argc
; i
++) {
875 const char *arg
= argv
[i
];
878 if (!strcmp(arg
, "--")) {
882 if (!strcmp(arg
, "-a")) {
886 if (!strcmp(arg
, "-p")) {
887 flags
|= CHECK_PLAYLISTS
;
890 if (!strcmp(arg
, "-m")) {
891 flags
|= CHECK_MOODS
;
894 return -E_AFS_SYNTAX
;
897 return -E_AFS_SYNTAX
;
900 if (flags
& CHECK_AFT
) {
901 ret
= send_callback_request(aft_check_callback
, NULL
, &result
);
905 ret
= send_buffer(fd
, (char *) result
.data
);
911 if (flags
& CHECK_PLAYLISTS
) {
912 ret
= send_callback_request(playlist_check_callback
, NULL
, &result
);
916 ret
= send_buffer(fd
, (char *) result
.data
);