/*
- * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2013 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
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;
+ /** 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 */
-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 **inbufp;
- /**
- * The output buffer of the filter chain.
- *
- * Points to the output buffer of the last filter in the filter chain.
- */
- char **outbufp;
- /** 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 task task;
-};
-
-#define FOR_EACH_FILTER_NODE(fn, fc, i) for (i = 0; i < (fc)->num_filters \
- && (fn = (fc)->filter_nodes + i); i++)
-
/**
* The structure associated with a paraslash filter.
*
* 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);
/**
* argv. On failure, a negative paraslash error code must be returned.
*/
int (*parse_config)(int argc, char **argv, void **config);
+ /**
+ * Deallocate the memory for the configuration.
+ *
+ * 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.
+ *
+ * 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.
+ */
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.
+ * Pointer to the converting function of the filter. On errors, the
+ * post_select function is supposed to return a negative error code.
+ */
+ int (*post_select)(struct sched *s, struct task *t);
+ /**
+ * Answer a buffer tree query.
+ *
+ * This optional function pointer is used for inter node communications
+ * of the buffer tree nodes. See \ref btr_command_handler for details.
*/
- void (*post_select)(struct sched *s, struct task *t);
btr_command_handler execute;
};
void filter_init(void);
int check_filter_arg(char *filter_arg, void **conf);
-void print_filter_helps(int detailed);
+void print_filter_helps(unsigned flags);
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)
{
DECLARE_FILTER_INITS
+/** 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. */
projects / paraslash.git / blobdiff