jack2/common/driver_interface.h

/*
  Copyright (C) 2003 Bob Ham <rah@bash.sh>
  Copyright (C) 2008 Nedko Arnaudov <nedko@arnaudov.name>

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

*/

#ifndef __jack_driver_interface_h__
#define __jack_driver_interface_h__

#ifdef __cplusplus
extern "C"
{
#endif

#include <limits.h>
#include "jslist.h"

#include "JackCompilerDeps.h"
#include "JackSystemDeps.h"

#define JACK_DRIVER_NAME_MAX          15
#define JACK_DRIVER_PARAM_NAME_MAX    15
#define JACK_DRIVER_PARAM_STRING_MAX  127
#define JACK_DRIVER_PARAM_DESC        255
#define JACK_PATH_MAX                 511

#define JACK_CONSTRAINT_FLAG_RANGE       ((uint32_t)1) /**< if set, constraint is a range (min-max) */
#define JACK_CONSTRAINT_FLAG_STRICT      ((uint32_t)2) /**< if set, constraint is strict, i.e. supplying non-matching value will not work */
#define JACK_CONSTRAINT_FLAG_FAKE_VALUE  ((uint32_t)4) /**< if set, values have no user meaningful meaning */

/** Driver parameter types */
typedef enum
{
    JackDriverParamInt = 1,
    JackDriverParamUInt,
    JackDriverParamChar,
    JackDriverParamString,
    JackDriverParamBool
} jack_driver_param_type_t;

/** Driver types */
typedef enum
{
    JackDriverMaster = 1,
    JackDriverSlave,
    JackDriverNone,
} jack_driver_type_t;

/** Driver parameter value */
typedef union
{
    uint32_t ui;
    int32_t i;
    char c;
    char str[JACK_DRIVER_PARAM_STRING_MAX + 1];
} jack_driver_param_value_t;

typedef struct {
    jack_driver_param_value_t value;
    char short_desc[64];               /**< A short (~30 chars) description for the user */
} jack_driver_param_value_enum_t;

struct jack_constraint_enum_uint32_descriptor {
    uint32_t value;
    const char * short_desc;
};

struct jack_constraint_enum_sint32_descriptor {
    int32_t value;
    const char * short_desc;
};

struct jack_constraint_enum_char_descriptor {
    char value;
    const char * short_desc;
};

struct jack_constraint_enum_str_descriptor {
    const char * value;
    const char * short_desc;
};

typedef struct {
    uint32_t flags;         /**< JACK_CONSTRAINT_FLAG_XXX */
    union {
        struct {
            jack_driver_param_value_t min;
            jack_driver_param_value_t max;
        } range;            /**< valid when JACK_CONSTRAINT_FLAG_RANGE flag is set */

        struct {
            uint32_t count;
            jack_driver_param_value_enum_t * possible_values_array;
        } enumeration;      /**< valid when JACK_CONSTRAINT_FLAG_RANGE flag is not set */
    } constraint;
} jack_driver_param_constraint_desc_t;

/** A driver parameter descriptor */
typedef struct {
    char name[JACK_DRIVER_NAME_MAX + 1]; /**< The parameter's name */
    char character;                    /**< The parameter's character (for getopt, etc) */
    jack_driver_param_type_t type;     /**< The parameter's type */
    jack_driver_param_value_t value;   /**< The parameter's (default) value */
    jack_driver_param_constraint_desc_t * constraint; /**< Pointer to parameter constraint descriptor. NULL if there is no constraint */
    char short_desc[64];               /**< A short (~30 chars) description for the user */
    char long_desc[1024];              /**< A longer description for the user */
}
jack_driver_param_desc_t;

/** A driver parameter */
typedef struct {
    char character;
    jack_driver_param_value_t value;
}
jack_driver_param_t;

/** A struct for describing a jack driver */
typedef struct {
    char name[JACK_DRIVER_NAME_MAX + 1];      /**< The driver's canonical name */
    jack_driver_type_t type;               /**< The driver's type */
    char desc[JACK_DRIVER_PARAM_DESC + 1];    /**< The driver's extended description */
#ifdef WIN32
    wchar_t file[JACK_PATH_MAX + 1];             /**< The filename of the driver's shared object file */
#else
    char file[JACK_PATH_MAX + 1];             /**< The filename of the driver's shared object file */
#endif
    uint32_t nparams;                         /**< The number of parameters the driver has */
    jack_driver_param_desc_t * params;        /**< An array of parameter descriptors */
}
jack_driver_desc_t;

typedef struct {
    uint32_t size;          /* size of the param array, in elements */
}
jack_driver_desc_filler_t;

int jack_parse_driver_params(jack_driver_desc_t * desc, int argc, char* argv[], JSList ** param_ptr);

// To be used by drivers

SERVER_EXPORT jack_driver_desc_t *            /* Newly allocated driver descriptor, NULL on failure */
jack_driver_descriptor_construct(
    const char * name,          /* Driver name */
    jack_driver_type_t type,    /* Driver type */
    const char * description,   /* Driver description */
    jack_driver_desc_filler_t * filler); /* Pointer to stack var to be supplied to jack_driver_descriptor_add_parameter() as well.
                                            Can be NULL for drivers that have no parameters. */

SERVER_EXPORT int                            /* 0 on failure */
jack_driver_descriptor_add_parameter(
    jack_driver_desc_t * driver_descr,  /* Pointer to driver descriptor as returned by jack_driver_descriptor_construct() */
    jack_driver_desc_filler_t * filler, /* Pointer to the stack var that was supplied to jack_driver_descriptor_add_parameter(). */
    const char * name,                  /* Parameter's name */
    char character,                     /* Parameter's character (for getopt, etc) */
    jack_driver_param_type_t type,      /* The parameter's type */
    const jack_driver_param_value_t * value_ptr, /* Pointer to parameter's (default) value */
    jack_driver_param_constraint_desc_t * constraint, /* Pointer to parameter constraint descriptor. NULL if there is no constraint */
    const char * short_desc,            /* A short (~30 chars) description for the user */
    const char * long_desc);            /* A longer description for the user, if NULL short_desc will be used */

SERVER_EXPORT
int jack_constraint_add_enum(
    jack_driver_param_constraint_desc_t ** constraint_ptr_ptr,
    uint32_t * array_size_ptr,
    jack_driver_param_value_t * value_ptr,
    const char * short_desc);

SERVER_EXPORT
void jack_constraint_free(jack_driver_param_constraint_desc_t * constraint_ptr);

#define JACK_CONSTRAINT_COMPOSE_ENUM(type) \
SERVER_EXPORT                              \
jack_driver_param_constraint_desc_t *      \
jack_constraint_compose_enum_ ## type(     \
    uint32_t flags,                        \
    struct jack_constraint_enum_ ## type ## _descriptor * descr_array_ptr)

JACK_CONSTRAINT_COMPOSE_ENUM(uint32);
JACK_CONSTRAINT_COMPOSE_ENUM(sint32);
JACK_CONSTRAINT_COMPOSE_ENUM(char);
JACK_CONSTRAINT_COMPOSE_ENUM(str);

typedef jack_driver_desc_t * (*JackDriverDescFunction) ();

#ifdef __cplusplus
}
#endif

#endif /* __jack_driver_interface_h__ */