common.h

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/*
** Copyright (c) 2002-2016, Erik de Castro Lopo <erikd@mega-nerd.com>
** All rights reserved.
**
** This code is released under 2-clause BSD license. Please see the
** file at : https://github.com/erikd/libsamplerate/blob/master/COPYING
*/

#ifndef COMMON_H_INCLUDED
#define COMMON_H_INCLUDED

#ifdef HAVE_STDINT_H
#include <stdint.h>
#elif (SIZEOF_INT == 4)
typedef int     int32_t ;
#elif (SIZEOF_LONG == 4)
typedef long    int32_t ;
#endif

#define SRC_MAX_RATIO           256
#define SRC_MAX_RATIO_STR       "256"

#define SRC_MIN_RATIO_DIFF      (1e-20)

#define MAX(a,b)    (((a) > (b)) ? (a) : (b))
#define MIN(a,b)    (((a) < (b)) ? (a) : (b))

#define ARRAY_LEN(x)            ((int) (sizeof (x) / sizeof ((x) [0])))
#define OFFSETOF(type,member)   ((int) (&((type*) 0)->member))

#define MAKE_MAGIC(a,b,c,d,e,f) ((a) + ((b) << 4) + ((c) << 8) + ((d) << 12) + ((e) << 16) + ((f) << 20))

/*
** Inspiration : http://sourcefrog.net/weblog/software/languages/C/unused.html
*/
#ifdef UNUSED
#elif defined (__GNUC__)
#   define UNUSED(x) UNUSED_ ## x __attribute__ ((unused))
#elif defined (__LCLINT__)
#   define UNUSED(x) /*@unused@*/ x
#else
#   define UNUSED(x) x
#endif

#ifdef __GNUC__
#   define WARN_UNUSED  __attribute__ ((warn_unused_result))
#else
#   define WARN_UNUSED
#endif


#include "samplerate.h"

enum
{   SRC_FALSE   = 0,
    SRC_TRUE    = 1,

    SRC_MODE_PROCESS    = 555,
    SRC_MODE_CALLBACK   = 556
} ;

enum
{   SRC_ERR_NO_ERROR = 0,

    SRC_ERR_MALLOC_FAILED,
    SRC_ERR_BAD_STATE,
    SRC_ERR_BAD_DATA,
    SRC_ERR_BAD_DATA_PTR,
    SRC_ERR_NO_PRIVATE,
    SRC_ERR_BAD_SRC_RATIO,
    SRC_ERR_BAD_PROC_PTR,
    SRC_ERR_SHIFT_BITS,
    SRC_ERR_FILTER_LEN,
    SRC_ERR_BAD_CONVERTER,
    SRC_ERR_BAD_CHANNEL_COUNT,
    SRC_ERR_SINC_BAD_BUFFER_LEN,
    SRC_ERR_SIZE_INCOMPATIBILITY,
    SRC_ERR_BAD_PRIV_PTR,
    SRC_ERR_BAD_SINC_STATE,
    SRC_ERR_DATA_OVERLAP,
    SRC_ERR_BAD_CALLBACK,
    SRC_ERR_BAD_MODE,
    SRC_ERR_NULL_CALLBACK,
    SRC_ERR_NO_VARIABLE_RATIO,
    SRC_ERR_SINC_PREPARE_DATA_BAD_LEN,
    SRC_ERR_BAD_INTERNAL_STATE,

    /* This must be the last error number. */
    SRC_ERR_MAX_ERROR
} ;

typedef struct SRC_PRIVATE_tag
{   double  last_ratio, last_position ;

    int     error ;
    int     channels ;

    /* SRC_MODE_PROCESS or SRC_MODE_CALLBACK */
    int     mode ;

    /* Pointer to data to converter specific data. */
    void    *private_data ;

    /* Varispeed process function. */
    int     (*vari_process) (struct SRC_PRIVATE_tag *psrc, SRC_DATA *data) ;

    /* Constant speed process function. */
    int     (*const_process) (struct SRC_PRIVATE_tag *psrc, SRC_DATA *data) ;

    /* State reset. */
    void    (*reset) (struct SRC_PRIVATE_tag *psrc) ;

    /* Data specific to SRC_MODE_CALLBACK. */
    src_callback_t  callback_func ;
    void            *user_callback_data ;
    long            saved_frames ;
    const float     *saved_data ;
} SRC_PRIVATE ;

/* In src_sinc.c */
const char* sinc_get_name (int src_enum) ;
const char* sinc_get_description (int src_enum) ;

int sinc_set_converter (SRC_PRIVATE *psrc, int src_enum) ;

/* In src_linear.c */
const char* linear_get_name (int src_enum) ;
const char* linear_get_description (int src_enum) ;

int linear_set_converter (SRC_PRIVATE *psrc, int src_enum) ;

/* In src_zoh.c */
const char* zoh_get_name (int src_enum) ;
const char* zoh_get_description (int src_enum) ;

int zoh_set_converter (SRC_PRIVATE *psrc, int src_enum) ;

/*----------------------------------------------------------
**  Common static inline functions.
*/

static inline double
fmod_one (double x)
{   double res ;

    res = x - lrint (x) ;
    if (res < 0.0)
        return res + 1.0 ;

    return res ;
} /* fmod_one */

static inline int
is_bad_src_ratio (double ratio)
{   return (ratio < (1.0 / SRC_MAX_RATIO) || ratio > (1.0 * SRC_MAX_RATIO)) ;
} /* is_bad_src_ratio */


#endif  /* COMMON_H_INCLUDED */