audio_node.h

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/* SPDX-License-Identifier: GPL-3.0-or-later */
 
#ifndef OVE_AUDIO_NODE_H
#define OVE_AUDIO_NODE_H
 
#ifdef __cplusplus
extern "C" {
#endif
 
#include <stdint.h>
 
#include "ove/storage.h"
 
#define OVE_AUDIO_MAX_CHANNELS 8
 
/* ── Sample format ──────────────────────────────────────────────── */
 
enum ove_audio_sample_fmt {
    OVE_AUDIO_FMT_S16, 
    OVE_AUDIO_FMT_S32, 
    OVE_AUDIO_FMT_F32, 
};
 
static inline unsigned int ove_audio_sample_size(enum ove_audio_sample_fmt fmt)
{
    switch (fmt) {
    case OVE_AUDIO_FMT_S16:
        return sizeof(int16_t);
    case OVE_AUDIO_FMT_S32:
        return sizeof(int32_t);
    case OVE_AUDIO_FMT_F32:
        return sizeof(float);
    default:
        return 0;
    }
}
 
/* ── Audio format descriptor ────────────────────────────────────── */
 
struct ove_audio_fmt {
    unsigned int sample_rate;         
    unsigned int channels;            
    enum ove_audio_sample_fmt sample_fmt; 
};
 
static inline int ove_audio_fmt_equal(const struct ove_audio_fmt *a, const struct ove_audio_fmt *b)
{
    return a->sample_rate == b->sample_rate && a->channels == b->channels &&
           a->sample_fmt == b->sample_fmt;
}
 
/* ── Audio buffer ───────────────────────────────────────────────── */
 
struct ove_audio_buf {
    void *data;          
    unsigned int frames;         
    const struct ove_audio_fmt *fmt; 
};
 
/* ── Node vtable ────────────────────────────────────────────────── */
 
struct ove_audio_node_ops {
    int (*configure)(void *ctx, const struct ove_audio_fmt *in_fmt,
             struct ove_audio_fmt *out_fmt);
 
    int (*start)(void *ctx);
 
    int (*stop)(void *ctx);
 
    int (*process)(void *ctx, const struct ove_audio_buf *in, struct ove_audio_buf *out);
 
    void (*destroy)(void *ctx);
};
 
/* ── Node types ─────────────────────────────────────────────────── */
 
enum ove_audio_node_type {
    OVE_AUDIO_NODE_SOURCE,    
    OVE_AUDIO_NODE_PROCESSOR, 
    OVE_AUDIO_NODE_SINK,      
};
 
struct ove_audio_node {
    const char *name;             
    enum ove_audio_node_type type;        
    const struct ove_audio_node_ops *ops; 
    void *ctx;            
    struct ove_audio_fmt out_fmt; 
};
 
/* ── Built-in node factories ────────────────────────────────────── */
 
struct ove_audio_graph; /* forward declaration */
 
struct ove_audio_channel_map {
    unsigned int out_channels;   
    int map[OVE_AUDIO_MAX_CHANNELS]; 
};
 
typedef void (*ove_audio_tap_fn)(const struct ove_audio_buf *buf, void *user_data);
 
/* The built-in factory functions below internally allocate a per-node
 * context with OVE_BACKEND_MALLOC.  Under CONFIG_OVE_ZERO_HEAP the gate
 * OVE_HEAP_AUDIO hides them: link fails rather than silently trapping,
 * nudging the application toward its own static-context processor nodes. */
#ifdef OVE_HEAP_AUDIO
 
int ove_audio_node_converter(struct ove_audio_graph *g, enum ove_audio_sample_fmt target_fmt,
                 const char *name);
 
int ove_audio_node_channel_map(struct ove_audio_graph *g, const struct ove_audio_channel_map *map,
                   const char *name);
 
int ove_audio_node_gain(struct ove_audio_graph *g, float gain_db, const char *name);
 
int ove_audio_node_tap(struct ove_audio_graph *g, ove_audio_tap_fn fn, void *user_data,
               const char *name);
 
#endif /* OVE_HEAP_AUDIO */
 
#ifdef __cplusplus
}
#endif
 
 
#endif /* OVE_AUDIO_NODE_H */