Initial load of CODEC2/FreeDV software and wrapper

DSP_API/circular_buffer.c

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+/* *****************************************************************************
+ *	circular_float_buffer.c											2014 AUG 20
+ *
+ *	General Purpose Circular Buffer Function Set
+ *
+ *  Created on: Aug 21, 2014
+ *      Author: Graham / KE9H
+ *
+ * *****************************************************************************
+ *
+ *	Copyright (C) 2014 FlexRadio Systems.
+ *	This program is free software: you can redistribute it and/or modify
+ *	it under the terms of the GNU General Public License as published by
+ *	the Free Software Foundation, either version 3 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 General Public License for more details.
+ *	You should have received a copy of the GNU General Public License
+ *	along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ *******************************************************************************
+ *
+ *	Example usage:
+ *
+ *	Circular buffer object, declared in circular_buffer.h
+ *
+ * 		typedef struct {
+ *			unsigned int  size;		// Maximum number of elements + 1
+ *			unsigned int  start;	// Index of oldest element
+ *			unsigned int  end;		// Index at which to write new element
+ *			unsigned char *elems;	// Vector of elements
+ *		} circular_buffer, *Circular_Buffer;
+ *
+ *
+ *	Circular Buffer Declaration
+ *
+ *		unsigned char CL_Buff[2048];		// Example: Command Line Buffer
+ *		Note: Make sure declaration matches data size
+ *
+ *		circular_buffer CommandLine_cb;
+ *
+ *		Circular_Buffer CL_cb = &CommandLine_cb;
+ *
+ *
+ *	Initialize circular buffer for Command Line buffer
+ *	// Includes one empty element
+ *		CL_cb->size	 = 2048;		// size = no.elements in array
+ *		CL_cb->start = 0;
+ *		CL_cb->end	 = 0;
+ *		CL_cb->elems = CL_Buff;
+ *
+ *	Call Read or Write function, appropriate to the data size
+ *
+ **************************************************************************** */
+
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "circular_buffer.h"
+
+
+
+/* *****************************************************************************
+ *	BOOL cfbIsFull(Circular_Float_Buffer cb)
+ *		Test to check if the buffer is FULL
+ *		Returns TRUE if full
+ */
+
+bool cfbIsFull(Circular_Float_Buffer cb)
+{
+	return ((cb->end + 1) % cb->size == cb->start);
+}
+
+
+/* *****************************************************************************
+ *	BOOL cfbIsEmpty(Circular_Float_Buffer cb)
+ *		Test to check if the buffer is EMPTY
+ *		Returns TRUE if empty
+ */
+
+bool cfbIsEmpty(Circular_Float_Buffer cb)
+{
+	return cb->end == cb->start;
+}
+
+
+/* *****************************************************************************
+ *	void cbWriteChar(Circular_Buffer cb, unsigned char temp)
+ *		Write an element, overwriting oldest element if buffer is full.
+ *		App can choose to avoid the overwrite by checking cbIsFull().
+ */
+
+void cbWriteFloat(Circular_Float_Buffer cb, float sample)
+{
+	cb->elems[cb->end] = sample;
+	cb->end = (cb->end + 1) % cb->size;
+	if (cb->end == cb->start)
+		cb->start = (cb->start + 1) % cb->size;		/* full, overwrite */
+}
+
+
+/* *****************************************************************************
+ *	unsigned char cbReadChar(CircularBuffer *cb)
+ *		Returns oldest element.
+ *		Calling function must ensure [cbIsEmpty() != TRUE], first.
+ */
+
+float cbReadFloat(Circular_Float_Buffer cb)
+{
+	float temp;
+
+	temp = cb->elems[cb->start];
+	cb->start = (cb->start + 1) % cb->size;
+	return temp;
+}
+
+
+/* *****************************************************************************
+ *	void zero_cfb(Circular_Float_Buffer cb)
+ *
+ *		Empties circular buffer
+ */
+
+void zero_cfb(Circular_Float_Buffer cb)
+{
+	cb->start = 0;
+	cb->end	 = 0;
+}
+
+
+/* *****************************************************************************
+ *	int cfbContains(Circular_Float_Buffer cb)
+ *
+ *		Returns the number of samples in the circular buffer
+ *
+ */
+
+int cfbContains(Circular_Float_Buffer cb)
+{
+	int contains;
+
+	contains = (cb->end - cb->start);
+	if (contains < 0)
+		contains += cb->size;
+
+	return contains;
+}
+
+
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  SHORT BUFFER ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+
+/* *****************************************************************************
+ *	BOOL cfbIsFull(Circular_Float_Buffer cb)
+ *		Test to check if the buffer is FULL
+ *		Returns TRUE if full
+ */
+
+bool csbIsFull(Circular_Short_Buffer cb)
+{
+	return ((cb->end + 1) % cb->size == cb->start);
+}
+
+
+/* *****************************************************************************
+ *	BOOL csbIsEmpty(Circular_Short_Buffer cb)
+ *		Test to check if the buffer is EMPTY
+ *		Returns TRUE if empty
+ */
+
+bool csbIsEmpty(Circular_Short_Buffer cb)
+{
+	return cb->end == cb->start;
+}
+
+
+/* *****************************************************************************
+ *	void cbWriteChar(Circular_Buffer cb, unsigned char temp)
+ *		Write an element, overwriting oldest element if buffer is full.
+ *		App can choose to avoid the overwrite by checking cbIsFull().
+ */
+
+void cbWriteShort(Circular_Short_Buffer cb, short sample)
+{
+	cb->elems[cb->end] = sample;
+	cb->end = (cb->end + 1) % cb->size;
+	if (cb->end == cb->start)
+		cb->start = (cb->start + 1) % cb->size;		/* full, overwrite */
+}
+
+
+/* *****************************************************************************
+ *	unsigned char cbReadShort(Circular_Short_Buffer *cb)
+ *		Returns oldest element.
+ *		Calling function must ensure [csbIsEmpty() != TRUE], first.
+ */
+
+short cbReadShort(Circular_Short_Buffer cb)
+{
+	short temp;
+
+	temp = cb->elems[cb->start];
+	cb->start = (cb->start + 1) % cb->size;
+	return temp;
+}
+
+
+/* *****************************************************************************
+ *	void zero_cfb(Circular_Short_Buffer cb)
+ *
+ *		Empties circular buffer
+ */
+
+void zero_csb(Circular_Short_Buffer cb)
+{
+	cb->start = 0;
+	cb->end	 = 0;
+}
+
+
+/* *****************************************************************************
+ *	int csbContains(Circular_Short_Buffer cb)
+ *
+ *		Returns the number of samples in the circular buffer
+ *
+ */
+
+int csbContains(Circular_Short_Buffer cb)
+{
+	int contains;
+
+	contains = (cb->end - cb->start);
+	if (contains < 0)
+		contains += cb->size;
+
+		return contains;
+}
+
+
+// EoF =====-----
+