audio_node.h

/* 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>
 
#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 */
 
int ove_audio_node_converter(struct ove_audio_graph *g,
                             enum ove_audio_sample_fmt target_fmt,
                             const char *name);
 
struct ove_audio_channel_map {
    unsigned int out_channels;                   
    int          map[OVE_AUDIO_MAX_CHANNELS];    
};
 
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);
 
typedef void (*ove_audio_tap_fn)(const struct ove_audio_buf *buf,
                                 void *user_data);
 
int ove_audio_node_tap(struct ove_audio_graph *g,
                       ove_audio_tap_fn fn, void *user_data,
                       const char *name);
 
#ifdef __cplusplus
}
#endif
 
 
#endif /* OVE_AUDIO_NODE_H */