include/global.h

/**
 * \file include/global.h
 * \brief Application interface library for the ALSA driver
 * \author Jaroslav Kysela <perex@perex.cz>
 * \author Abramo Bagnara <abramo@alsa-project.org>
 * \author Takashi Iwai <tiwai@suse.de>
 * \date 1998-2001
 *
 * Application interface library for the ALSA driver
 */
/*
 *   This library 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 library; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#ifndef __ALSA_GLOBAL_H_
#define __ALSA_GLOBAL_H_

/* for timeval and timespec */
#include <time.h>

#ifdef __cplusplus
extern "C" {
#endif

/**
 *  \defgroup Global Global defines and functions
 *  Global defines and functions.
 *  \par
 *  The ALSA library implementation uses these macros and functions.
 *  Most applications probably do not need them.
 *  \{
 */

const char *snd_asoundlib_version(void);

#ifndef ATTRIBUTE_UNUSED
/** do not print warning (gcc) when function parameter is not used */
#define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
#endif

#ifndef __STRING
/** \brief Return 'x' argument as string */
#define __STRING(x)     #x
#endif

#ifdef PIC /* dynamic build */

/** \hideinitializer \brief Helper macro for #SND_DLSYM_BUILD_VERSION. */
#define __SND_DLSYM_VERSION(name, version) _ ## name ## version
/**
 * \hideinitializer
 * \brief Appends the build version to the name of a versioned dynamic symbol.
 */
#define SND_DLSYM_BUILD_VERSION(name, version) char __SND_DLSYM_VERSION(name, version);

#else /* static build */

struct snd_dlsym_link {
	struct snd_dlsym_link *next;
	const char *dlsym_name;
	const void *dlsym_ptr;
};

extern struct snd_dlsym_link *snd_dlsym_start;

/** \hideinitializer \brief Helper macro for #SND_DLSYM_BUILD_VERSION. */
#define __SND_DLSYM_VERSION(prefix, name, version) _ ## prefix ## name ## version
/**
 * \hideinitializer
 * \brief Appends the build version to the name of a versioned dynamic symbol.
 */
#define SND_DLSYM_BUILD_VERSION(name, version) \
  static struct snd_dlsym_link __SND_DLSYM_VERSION(snd_dlsym_, name, version); \
  void __SND_DLSYM_VERSION(snd_dlsym_constructor_, name, version) (void) __attribute__ ((constructor)); \
  void __SND_DLSYM_VERSION(snd_dlsym_constructor_, name, version) (void) { \
    __SND_DLSYM_VERSION(snd_dlsym_, name, version).next = snd_dlsym_start; \
    __SND_DLSYM_VERSION(snd_dlsym_, name, version).dlsym_name = __STRING(name); \
    __SND_DLSYM_VERSION(snd_dlsym_, name, version).dlsym_ptr = (void *)&name; \
    snd_dlsym_start = &__SND_DLSYM_VERSION(snd_dlsym_, name, version); \
  }

#endif

/** \brief Returns the version of a dynamic symbol as a string. */
#define SND_DLSYM_VERSION(version) __STRING(version)

int snd_dlpath(char *path, size_t path_len, const char *name);
void *snd_dlopen(const char *file, int mode, char *errbuf, size_t errbuflen);
void *snd_dlsym(void *handle, const char *name, const char *version);
int snd_dlclose(void *handle);


/** \brief alloca helper macro. */
#define __snd_alloca(ptr,type) do { *ptr = (type##_t *) alloca(type##_sizeof()); memset(*ptr, 0, type##_sizeof()); } while (0)

/**
 * \brief Internal structure for an async notification client handler.
 *
 * The ALSA library uses a pointer to this structure as a handle to an async
 * notification object. Applications don't access its contents directly.
 */
typedef struct _snd_async_handler snd_async_handler_t;

/**
 * \brief Async notification callback.
 *
 * See the #snd_async_add_handler function for details.
 */
typedef void (*snd_async_callback_t)(snd_async_handler_t *handler);

int snd_async_add_handler(snd_async_handler_t **handler, int fd, 
			  snd_async_callback_t callback, void *private_data);
int snd_async_del_handler(snd_async_handler_t *handler);
int snd_async_handler_get_fd(snd_async_handler_t *handler);
int snd_async_handler_get_signo(snd_async_handler_t *handler);
void *snd_async_handler_get_callback_private(snd_async_handler_t *handler);

struct snd_shm_area *snd_shm_area_create(int shmid, void *ptr);
struct snd_shm_area *snd_shm_area_share(struct snd_shm_area *area);
int snd_shm_area_destroy(struct snd_shm_area *area);

int snd_user_file(const char *file, char **result);

#ifdef __GLIBC__
#if !defined(_POSIX_C_SOURCE) && !defined(_POSIX_SOURCE)
struct timeval {
	time_t		tv_sec;		/* seconds */
	long		tv_usec;	/* microseconds */
};

struct timespec {
	time_t		tv_sec;		/* seconds */
	long		tv_nsec;	/* nanoseconds */
};
#endif
#endif

/** Timestamp */
typedef struct timeval snd_timestamp_t;
/** Hi-res timestamp */
typedef struct timespec snd_htimestamp_t;

/** \} */

#ifdef __cplusplus
}
#endif

#endif /* __ALSA_GLOBAL_H */