--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/alsa/pcm_ioplug.h	Tue Mar 18 17:55:14 2025 -0400
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+/**
+ * \file include/pcm_ioplug.h
+ * \brief External I/O-Plugin SDK
+ * \author Takashi Iwai <tiwai@suse.de>
+ * \date 2005
+ *
+ * External I/O-Plugin SDK
+ */
+
+/*
+ * ALSA external PCM plugin SDK
+ *
+ * Copyright (c) 2005 Takashi Iwai <tiwai@suse.de>
+ *
+ *   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_PCM_IOPLUG_H
+#define __ALSA_PCM_IOPLUG_H
+
+/**
+ * \defgroup PCM_IOPlug External I/O plugin SDK
+ * \ingroup Plugin_SDK
+ * See the \ref pcm page for more details.
+ * \{
+ */
+
+/** hw constraints for ioplug */
+enum {
+	SND_PCM_IOPLUG_HW_ACCESS = 0,	/**< access type */
+	SND_PCM_IOPLUG_HW_FORMAT,	/**< format */
+	SND_PCM_IOPLUG_HW_CHANNELS,	/**< channels */
+	SND_PCM_IOPLUG_HW_RATE,		/**< rate */
+	SND_PCM_IOPLUG_HW_PERIOD_BYTES,	/**< period bytes */
+	SND_PCM_IOPLUG_HW_BUFFER_BYTES,	/**< buffer bytes */
+	SND_PCM_IOPLUG_HW_PERIODS,	/**< number of periods */
+	SND_PCM_IOPLUG_HW_PARAMS	/**< max number of hw constraints */
+};
+	
+/** I/O plugin handle */
+typedef struct snd_pcm_ioplug snd_pcm_ioplug_t;
+/** Callback table of ioplug */
+typedef struct snd_pcm_ioplug_callback snd_pcm_ioplug_callback_t;
+#ifdef DOC_HIDDEN
+/* redefine typedefs for stupid doxygen */
+typedef snd_pcm_ioplug snd_pcm_ioplug_t;
+typedef snd_pcm_ioplug_callback snd_pcm_ioplug_callback_t;
+#endif
+
+/*
+ * bit flags for additional conditions
+ */
+#define SND_PCM_IOPLUG_FLAG_LISTED	(1<<0)		/**< list up this PCM */
+#define SND_PCM_IOPLUG_FLAG_MONOTONIC	(1<<1)		/**< monotonic timestamps */
+/** hw pointer wrap around at boundary instead of buffer_size */
+#define SND_PCM_IOPLUG_FLAG_BOUNDARY_WA	(1<<2)
+
+/*
+ * Protocol version
+ */
+#define SND_PCM_IOPLUG_VERSION_MAJOR	1	/**< Protocol major version */
+#define SND_PCM_IOPLUG_VERSION_MINOR	0	/**< Protocol minor version */
+#define SND_PCM_IOPLUG_VERSION_TINY	2	/**< Protocol tiny version */
+/**
+ * IO-plugin protocol version
+ */
+#define SND_PCM_IOPLUG_VERSION		((SND_PCM_IOPLUG_VERSION_MAJOR<<16) |\
+					 (SND_PCM_IOPLUG_VERSION_MINOR<<8) |\
+					 (SND_PCM_IOPLUG_VERSION_TINY))
+
+/** Handle of ioplug */
+struct snd_pcm_ioplug {
+	/**
+	 * protocol version; #SND_PCM_IOPLUG_VERSION must be filled here
+	 * before calling #snd_pcm_ioplug_create()
+	 */
+	unsigned int version;
+	/**
+	 * name of this plugin; must be filled before calling #snd_pcm_ioplug_create()
+	 */
+	const char *name;
+	unsigned int flags;	/**< SND_PCM_IOPLUG_FLAG_XXX */
+	int poll_fd;		/**< poll file descriptor */
+	unsigned int poll_events;	/**< poll events */
+	unsigned int mmap_rw;		/**< pseudo mmap mode */
+	/**
+	 * callbacks of this plugin; must be filled before calling #snd_pcm_ioplug_create()
+	 */
+	const snd_pcm_ioplug_callback_t *callback;
+	/**
+	 * private data, which can be used freely in the driver callbacks
+	 */
+	void *private_data;
+	/**
+	 * PCM handle filled by #snd_pcm_ioplug_create()
+	 */
+	snd_pcm_t *pcm;
+
+	snd_pcm_stream_t stream;	/**< stream direcion; read-only */	
+	snd_pcm_state_t state;		/**< current PCM state; read-only */
+	volatile snd_pcm_uframes_t appl_ptr;	/**< application pointer; read-only */
+	volatile snd_pcm_uframes_t hw_ptr;	/**< hw pointer; read-only */
+	int nonblock;			/**< non-block mode; read-only */
+
+	snd_pcm_access_t access;	/**< access type; filled after hw_params is called */
+	snd_pcm_format_t format;	/**< PCM format; filled after hw_params is called */
+	unsigned int channels;		/**< number of channels; filled after hw_params is called */
+	unsigned int rate;		/**< rate; filled after hw_params is called */
+	snd_pcm_uframes_t period_size;	/**< period size; filled after hw_params is called */
+	snd_pcm_uframes_t buffer_size;	/**< buffer size; filled after hw_params is called */
+};
+
+/** Callback table of ioplug */
+struct snd_pcm_ioplug_callback {
+	/**
+	 * start the PCM; required, called inside mutex lock
+	 */
+	int (*start)(snd_pcm_ioplug_t *io);
+	/**
+	 * stop the PCM; required, called inside mutex lock
+	 */
+	int (*stop)(snd_pcm_ioplug_t *io);
+	/**
+	 * get the current DMA position; required, called inside mutex lock
+	 * \return buffer position up to buffer_size or
+	 * when #SND_PCM_IOPLUG_FLAG_BOUNDARY_WA flag is set up to boundary or
+	 * a negative error code for Xrun
+	 */
+	snd_pcm_sframes_t (*pointer)(snd_pcm_ioplug_t *io);
+	/**
+	 * transfer the data; optional, called inside mutex lock
+	 */
+	snd_pcm_sframes_t (*transfer)(snd_pcm_ioplug_t *io,
+				      const snd_pcm_channel_area_t *areas,
+				      snd_pcm_uframes_t offset,
+				      snd_pcm_uframes_t size);
+	/**
+	 * close the PCM; optional
+	 */
+	int (*close)(snd_pcm_ioplug_t *io);
+	/**
+	 * hw_params; optional
+	 */
+	int (*hw_params)(snd_pcm_ioplug_t *io, snd_pcm_hw_params_t *params);
+	/**
+	 * hw_free; optional
+	 */
+	int (*hw_free)(snd_pcm_ioplug_t *io);
+	/**
+	 * sw_params; optional
+	 */
+	int (*sw_params)(snd_pcm_ioplug_t *io, snd_pcm_sw_params_t *params);
+	/**
+	 * prepare; optional
+	 */
+	int (*prepare)(snd_pcm_ioplug_t *io);
+	/**
+	 * drain; optional
+	 */
+	int (*drain)(snd_pcm_ioplug_t *io);
+	/**
+	 * toggle pause; optional, called inside mutex lock
+	 */
+	int (*pause)(snd_pcm_ioplug_t *io, int enable);
+	/**
+	 * resume; optional
+	 */
+	int (*resume)(snd_pcm_ioplug_t *io);
+	/**
+	 * poll descriptors count; optional
+	 */
+	int (*poll_descriptors_count)(snd_pcm_ioplug_t *io);
+	/**
+	 * poll descriptors; optional
+	 */
+	int (*poll_descriptors)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int space);
+	/**
+	 * mangle poll events; optional
+	 */
+	int (*poll_revents)(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int nfds, unsigned short *revents);
+	/**
+	 * dump; optional
+	 */
+	void (*dump)(snd_pcm_ioplug_t *io, snd_output_t *out);
+	/**
+	 * get the delay for the running PCM; optional; since v1.0.1
+	 */
+	int (*delay)(snd_pcm_ioplug_t *io, snd_pcm_sframes_t *delayp);
+	/**
+	 * query the channel maps; optional; since v1.0.2
+	 */
+	snd_pcm_chmap_query_t **(*query_chmaps)(snd_pcm_ioplug_t *io);
+	/**
+	 * get the channel map; optional; since v1.0.2
+	 */
+	snd_pcm_chmap_t *(*get_chmap)(snd_pcm_ioplug_t *io);
+	/**
+	 * set the channel map; optional; since v1.0.2
+	 */
+	int (*set_chmap)(snd_pcm_ioplug_t *io, const snd_pcm_chmap_t *map);
+};
+
+
+int snd_pcm_ioplug_create(snd_pcm_ioplug_t *io, const char *name,
+			  snd_pcm_stream_t stream, int mode);
+int snd_pcm_ioplug_delete(snd_pcm_ioplug_t *io);
+
+/* update poll_fd and mmap_rw */
+int snd_pcm_ioplug_reinit_status(snd_pcm_ioplug_t *ioplug);
+
+/* get a mmap area (for mmap_rw only) */
+const snd_pcm_channel_area_t *snd_pcm_ioplug_mmap_areas(snd_pcm_ioplug_t *ioplug);
+
+/* clear hw_parameter setting */
+void snd_pcm_ioplug_params_reset(snd_pcm_ioplug_t *io);
+
+/* hw_parameter setting */
+int snd_pcm_ioplug_set_param_minmax(snd_pcm_ioplug_t *io, int type, unsigned int min, unsigned int max);
+int snd_pcm_ioplug_set_param_list(snd_pcm_ioplug_t *io, int type, unsigned int num_list, const unsigned int *list);
+
+/* change PCM status */
+int snd_pcm_ioplug_set_state(snd_pcm_ioplug_t *ioplug, snd_pcm_state_t state);
+
+/* calucalte the available frames */
+snd_pcm_uframes_t snd_pcm_ioplug_avail(const snd_pcm_ioplug_t * const ioplug,
+				       const snd_pcm_uframes_t hw_ptr,
+				       const snd_pcm_uframes_t appl_ptr);
+snd_pcm_uframes_t snd_pcm_ioplug_hw_avail(const snd_pcm_ioplug_t * const ioplug,
+					  const snd_pcm_uframes_t hw_ptr,
+					  const snd_pcm_uframes_t appl_ptr);
+
+/** \} */
+
+#endif /* __ALSA_PCM_IOPLUG_H */