X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=filter.h;h=94657a738a4ae1b620148d28400c20ed4c27a710;hp=321d763c1f9cb5b743db1cbbbf3f95f2f68774cb;hb=bda95f9508b456dcea89d300f6d4104e30ab9f3e;hpb=c79899fe6a1e8eb3086749f46c599d9790d99921 diff --git a/filter.h b/filter.h index 321d763c..94657a73 100644 --- a/filter.h +++ b/filter.h @@ -1,350 +1,146 @@ /* - * Copyright (C) 2005-2007 Andre Noll + * Copyright (C) 2005-2011 Andre Noll * - * 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 filter.h filter-related structures and exported symbols from filter_chain.c */ +/** \file filter.h Filter-related structures and exported symbols from filter_common.c. */ + +/** The list of supported filters. */ +enum filter_enum {FILTER_ENUM}; /** - * describes one running instance of a chain of filters + * Describes one running instance of a filter. +*/ +struct filter_node { + /** The number in the array of available filters. */ + unsigned filter_num; + /** + * Each filter may store any filter-specific information about the particular + * instance of the filter here. + */ + void *private_data; + /** The list of registered callbacks. */ + struct list_head callbacks; + /** A pointer to the configuration of this instance. */ + void *conf; + /** The buffer tree node. */ + struct btr_node *btrn; + /** The task corresponding to this filter node. */ + struct task task; + /** The minimal input queue size, see \ref btr_node_status(). */ + size_t min_iqs; +}; + +/** + * The structure associated with a paraslash filter. + * + * Paraslash filters are "modules" which are used to transform an audio stream. + * struct filter contains pointers to functions that must be supplied by the + * filter code in order to be used by the driving application (currently + * para_audiod and para_filter). * + * Note: As several instances of the same filter may be running at the same + * time, all these filter functions must be reentrant; no static non-constant + * variables may be used. + * \sa mp3dec_filter.c, oggdec_filter.c, wav_filter.c, compress_filter.c, filter_node */ -struct filter_chain { +struct filter { + /** The name of the filter. */ + const char *name; /** + * Pointer to the filter init routine. * - * - * the number of channels of the current stream - * - * Set by the decoding filter + * This function is only called once at startup. It must initialize the + * other non-optional function pointers of this structure. */ - unsigned int channels; + void (*init)(struct filter *f); /** + * Open one instance of this filter. * - * - * current samplerate in Hz - * - * Set by the decoding filter + * This should allocate the output buffer of the given filter node and do any + * other filter-specific preparations like initializing the private_data member + * of \a fn suitably. The open function is assumed to succeed. */ - unsigned int samplerate; + void (*open)(struct filter_node *fn); /** + * Close one instance of this filter. * - * - * the list containing all filter nodes in this filter chain + * Free all resources of associated with \a fn that were previously allocated + * by the open() function. It's OK to leave this alone if the filter does not + * need any cleanups. */ - struct list_head filters; + void (*close)(struct filter_node *fn); /** - * - * - * the input buffer of the filter chain - * - * This is set to point to the output buffer of the receiving application (the - * buffer used to read from stdin for para_filter; the output buffer of the - * current receiver for para_audiod) + * A pointer to the filter's command line parser. + * + * If this optional function pointer is not NULL, any filter options + * are passed from the main program to this command line parser once at + * application startup. The command line parser should check its + * command line options given by \a argc and \a argv and abort on + * errors. Success must be indicated by a non-negative return value. In + * this case the function should return a pointer to the + * filter-specific configuration data determined by \a argc and \a + * argv. On failure, a negative paraslash error code must be returned. */ - char *inbuf; + int (*parse_config)(int argc, char **argv, void **config); /** + * Deallocate the memory for the configuration. * - * - * the output buffer of the filter chain - * - * Points to the output buffer of the last filter in the filter chain - **/ - char *outbuf; + * This is called to free whatever ->parse_config() has allocated. + */ + void (*free_config)(void *conf); + + /** The help texts for this filter. */ + struct ggo_help help; /** + * Set scheduler timeout and add file descriptors to fd sets. * - * - * pointer to variable containing the number of bytes loaded in the input buffer + * This function is used to control the timeout value for select. It + * only allowed to decrease the current value. The second purpose of + * this function is to set file descriptors to be watched by the + * subsequent select call to the two fd sets. */ - size_t *in_loaded; + void (*pre_select)(struct sched *s, struct task *t); /** + * Convert (filter) the given data. * + * Pointer to the converting function of the filter. On errors, the + * post_select function is supposed to set t->error to a (negative) + * error code. + */ + void (*post_select)(struct sched *s, struct task *t); + /** + * Answer a buffer tree query. * - * pointer to variable containing the number of bytes loaded in the output buffer + * This optional function pointer is used for inter node communications + * of the buffer tree nodes. See \ref btr_command_handler for details. */ - size_t *out_loaded; - /** non-zero if this filter wont' produce any more output */ - int eof; - /** pointer to the eof flag of the receiving application */ - int *input_eof; - /** pointer to the eof flag of the writing application */ - int *output_eof; - /** the task associated with the filter chain */ - struct task task; -}; - -/** - * describes one running instance of a filter -*/ -struct filter_node { -/** - * - * - * a pointer to the corresponding filter struct - */ - struct filter *filter; -/** - * - * - * the filter chain this filter node belongs to - */ - struct filter_chain *fc; -/** - * - * - * the position of the filter in the corresponding filter chain - * - * all filters that make up the filter chains are organized in a doubly - * linked list. - */ - struct list_head node; -/** - * - * - * each filter may store any filter-specific information about the particular - * instance of the filter here. - */ - void *private_data; -/** - * - * - * the output buffer - */ - char *buf; -/** - * the size of the output buffer - */ - size_t bufsize; -/** - * - * - * the number of bytes currently loaded in \a buf - */ - size_t loaded; -/** - * - * - * the list of registered callbacks - */ - struct list_head callbacks; -/** - * - * a pointer to the configuration of this instance - */ - void *conf; -}; - -/** - * used to manage grab clients - * - * An application using paraslash's filter subsystem may register any number of - * callbacks for each filter_node. It is possible to attach a filter callback - * while the filter is running. This is used for stream grabbing in - * para_audiod: Whenever a client sends the 'grab' command, para_audiod adds a - * filter callback to the list of callbacks for the filter node specified in - * the grab command. - */ -struct filter_callback { -/** - * - * - * all callbacks are organized in a doubly linked list - */ - struct list_head node; -/** - * - * - * private data - * - * May be initialized by the application before registering the callback. This - * pointer is not used by the filter subsystem. It is provided for use within - * the input/ouput/close callback functions. - */ - void *data; -/** - * - * - * the input callback - * - * In not \p NULL, the filter subsystem calls this function whenever the filter - * consumed some or all of its input buffer. A pointer to the buffer of consumed - * data, its length and a pointer to the own \a filter_callback structure are passed - * to \a input_cb. The input callback is expected to return a negative value on errors. - */ - int (*input_cb)(char *buf, size_t len, struct filter_callback *fc); -/** - * - * - * the output callback - * - * If not NULL, this is called whenever the filter produces output. A pointer - * to the output data, its length and a pointer to the own \a filter_callback - * structure are passed to \a output_cb. Like the input callback, the output - * callback is expected to return a negative value on errors. - */ - int (*output_cb)(char *buf, size_t len, struct filter_callback *fc); -/** - * - * - * the callback close function - * - * This gets called whenever the input/ouput callback returned an error, or if - * the filter chain is going to be destroyed, e.g. because the end of the - * stream was encounterd. It is assumed to succeed. - */ - void (*close)(struct filter_callback *fc); + btr_command_handler execute; }; - -void close_filters(struct filter_chain *fc); -void filter_init(struct filter *all_filters); +void filter_init(void); int check_filter_arg(char *filter_arg, void **conf); -void filter_pre_select(__a_unused struct sched *s, struct task *t); +void print_filter_helps(int detailed); +void generic_filter_pre_select(struct sched *s, struct task *t); +int decoder_execute(const char *cmd, unsigned sample_rate, unsigned channels, + char **result); -/** - * the structure associated with a paraslash filter - * - * Paraslash filters are "modules" which are used to transform an audio stream. - * struct filter contains pointers to functions that must be supplied by the - * filter code in order to be used by the driving application (currently - * para_audiod and para_filter). - * - * Note: As several instances of the same filter may be running at the same - * time, all these filter functions must be reentrant; no static non-constant - * variables may be used. - * \sa mp3dec.c, oggdec.c, wav.c, compress.c, filter_node - */ -struct filter { -/** - * - * - * the name of the filter - */ -const char *name; -/** - * - * - * pointer to the filter init routine - * - * This function is only called once at startup. It must initialize the - * other non-optional function pointers of \a f. - */ -void (*init)(struct filter *f); -/** - * - * - * open one instance of this filter - * - * This should allocate the output buffer of the given filter node and do any - * other filter-specific preparations like initializing the private_data member - * of \a fn suitably. The open function is assumed to succeed. - */ -void (*open)(struct filter_node *fn); -/** - * - * - * convert (filter) the given data - * - * Pointer to the converting function of the filter. It should convert the - * given input buffer \a inbuf which is of length \a len to the previoulsy - * reserved output buffer of \a fn. On success, it must return the number of - * bytes it consumed from \a inbuf. On errors, a negative number indicating the - * kind of the error must be returned. - * - * A zero return value just means that nothing was converted (probably because - * the input buffer was too small). This is not interpreted as an error. - */ -ssize_t (*convert)(char *inbuf, size_t len, struct filter_node *fn); -/** - * - * - * close one instance of this filter - * - * Free all resources of associated with \a fn that were previously allocated - * by the open() function. - */ -void (*close)(struct filter_node *fn); -/** - * - * - * print the help text for this filter and exit - * - * This is optional and it is not necessary to initialize this pointer if - * the filter does not have a help text. - */ -void (*print_help)(void); -/** - * - * - * a pointer to the filter's command line parser - * - * If this optional function pointer is not NULL, any filter options are passed - * from the main propgram to this command line parser once at application - * startup. The command line parser should check its command line options given - * by \a argc and \a argv and abort on errors. On success, it should return a - * pointer to the filter-specific configuration data determined by \a argc and - * \a argv. - */ -void *(*parse_config)(int argc, char **argv); -}; -/** \cond */ -extern struct filter filters[]; -#define DECLARE_EXTERN_FILTER_INIT(name) \ - extern void name ## _init(struct filter *f) - -#define FILTER_INIT(filter) { \ - .name = #filter, \ - .init = filter ## _init, \ - .parse_config = NULL, \ - .print_help = NULL \ -}, - -/* filters that are always present */ -DECLARE_EXTERN_FILTER_INIT(wav); -/* wav is always the first filter */ -#define WAV_FILTER_NUM 0 -DECLARE_EXTERN_FILTER_INIT(compress); - -/* next the optional filters */ -#ifdef HAVE_MAD -DECLARE_EXTERN_FILTER_INIT(mp3dec); -#define MP3DEC_FILTER FILTER_INIT(mp3dec) +static inline void write_int16_host_endian(char *buf, int val) +{ +#ifdef WORDS_BIGENDIAN + *buf = val >> 8; + *(buf + 1) = val & 0xff; #else -#define MP3DEC_FILTER + *buf = val & 0xff; + *(buf + 1) = val >> 8; #endif +} -#ifdef HAVE_FAAD -DECLARE_EXTERN_FILTER_INIT(aacdec); -#define AACDEC_FILTER FILTER_INIT(aacdec) -#else -#define AACDEC_FILTER -#endif +DECLARE_FILTER_INITS -#ifdef HAVE_OGGVORBIS -DECLARE_EXTERN_FILTER_INIT(oggdec); -#define OGGDEC_FILTER FILTER_INIT(oggdec) -#else -#define OGGDEC_FILTER -#endif -/** \endcond */ +/** Iterate over the array of supported filters. */ +#define FOR_EACH_SUPPORTED_FILTER(j) for (j = 0; j < NUM_SUPPORTED_FILTERS; j++) -/** define an array of all available filters */ -#define DEFINE_FILTER_ARRAY(filters) struct filter filters[] = { \ - FILTER_INIT(wav) \ - FILTER_INIT(compress) \ - MP3DEC_FILTER \ - AACDEC_FILTER \ - OGGDEC_FILTER \ - { .name = NULL } }; +/** The filter array, one structure for each supported filter. */ +extern struct filter filters[NUM_SUPPORTED_FILTERS];