/*
- * Copyright (C) 2005-2007 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2011 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 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 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;
+};
/**
- * describes one running instance of a chain of filters
+ * 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);
-
-/**
- * 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);
-};
-
+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);
static inline void write_int16_host_endian(char *buf, int val)
{
#endif
}
+DECLARE_FILTER_INITS
-/** \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)
-#else
-#define MP3DEC_FILTER
-#endif
-
-#ifdef HAVE_FAAD
-DECLARE_EXTERN_FILTER_INIT(aacdec);
-#define AACDEC_FILTER FILTER_INIT(aacdec)
-#else
-#define AACDEC_FILTER
-#endif
-
-#ifdef HAVE_OGGVORBIS
-DECLARE_EXTERN_FILTER_INIT(oggdec);
-#define OGGDEC_FILTER FILTER_INIT(oggdec)
-#else
-#define OGGDEC_FILTER
-#endif
-/** \endcond */
-
-/** 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 } };
-
+/** Iterate over the array of supported filters. */
+#define FOR_EACH_SUPPORTED_FILTER(j) for (j = 0; j < NUM_SUPPORTED_FILTERS; j++)
+/** The filter array, one structure for each supported filter. */
+extern struct filter filters[NUM_SUPPORTED_FILTERS];
projects / paraslash.git / blobdiff