/*
- * Copyright (C) 2005-2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
*
* 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};
struct filter_node {
/** The number in the array of available filters. */
unsigned filter_num;
- /** The filter chain this filter node belongs to. */
- struct filter_chain *fc;
/**
* 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;
-};
-
-/** Describes one running instance of a chain of filters */
-struct filter_chain {
- /** The length of the filter chain. */
- unsigned int num_filters;
- /**
- * The number of channels of the current stream.
- *
- * Set by the decoding filter.
- */
- unsigned int channels;
- /**
- * Current sample rate in Hz.
- *
- * Set by the decoding filter.
- */
- unsigned int samplerate;
- /** The list containing all filter nodes in this filter chain. */
- struct filter_node *filter_nodes;
- /**
- * 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).
- */
- char *inbuf;
- /**
- * The output buffer of the filter chain.
- *
- * Points to the output buffer of the last filter in the filter chain.
- */
- char *outbuf;
- /** Contains the number of bytes loaded in the input buffer. */
- size_t *in_loaded;
- /** Contains the number of bytes loaded in the output buffer. */
- size_t *out_loaded;
- /** Pointer to the error variable of the receiving application. */
- int *input_error;
- /** Pointer to the error variable of the writing application. */
- int *output_error;
- /** The task associated with the filter chain. */
+ struct btr_node *btrn;
struct task task;
+ size_t min_iqs;
};
-#define FOR_EACH_FILTER_NODE(fn, fc, i) for (i = 0; i < (fc)->num_filters \
- && (fn = (fc)->filter_nodes + i); i++)
-
-
-/**
- * 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/output/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/output callback returned an error, or if
- * the filter chain is going to be destroyed, e.g. because the end of the
- * stream was encountered. It is assumed to succeed.
- */
- void (*close)(struct filter_callback *fc);
-};
-
-
/**
* The structure associated with a paraslash 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
+ * \sa mp3dec_filter.c, oggdec_filter.c, wav_filter.c, compress_filter.c, filter_node
*/
struct filter {
/** The name of the filter. */
* 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 previously
- * 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.
+ * by the open() function. It's OK to leave this alone if the filter does not
+ * need any cleanups.
*/
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.
*
* argv. On failure, a negative paraslash error code must be returned.
*/
int (*parse_config)(int argc, char **argv, void **config);
+ void (*free_config)(void *conf);
+
+ /** The help texts for this filter. */
+ struct ggo_help help;
+ void (*pre_select)(struct sched *s, struct task *t);
+ /**
+ * Convert (filter) the given data.
+ *
+ * Pointer to the converting function of the filter. It should convert as
+ * input data as possible. 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);
+ 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);
static inline void write_int16_host_endian(char *buf, int val)
{
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