comparison examples/basic_libpd/ringbuffer.h @ 338:1802f99cd77f prerelease

Initial support for thread-safe libpd (stil missing updated libpd binary), untested

+/*
+ *  Copyright (c) 2012 Peter Brinkmann ([e-mail])
+ *
+ *  For information on usage and redistribution, and for a DISCLAIMER OF ALL
+ *  WARRANTIES, see the file, "LICENSE.txt," in this distribution.
+ *
+ * See https://github.com/libpd/libpd/wiki for documentation
+ *
+ */
+
+#ifndef __OPENSL_RING_BUFFER_H__
+#define __OPENSL_RING_BUFFER_H__
+
+// Simple lock-free ring buffer implementation for one writer thread and one
+// consumer thread.
+typedef struct ring_buffer {
+    int size;
+    char *buf_ptr;
+    int write_idx;
+    int read_idx;
+} ring_buffer;
+
+// Creates a ring buffer (returns NULL on failure).
+ring_buffer *rb_create(int size);
+
+// Deletes a ring buffer.
+void rb_free(ring_buffer *buffer);
+
+// Returns the number of bytes that can currently be written; safe to be called
+// from any thread.
+int rb_available_to_write(ring_buffer *buffer);
+
+// Returns the number of bytes that can currently be read; safe to be called
+// from any thread.
+int rb_available_to_read(ring_buffer *buffer);
+
+// Writes bytes from n sources to the ring buffer (if the ring buffer has
+// enough space). The varargs are pairs of type (const char*, int) giving a
+// pointer to a buffer and the number of bytes to be copied. Only to be called
+// from a single writer thread.
+// Returns 0 on success.
+int rb_write_to_buffer(ring_buffer *buffer, int n, ...);
+
+// Reads the given number of bytes fromthe ring buffer to dest if the ring
+// buffer has enough data. Only to be called from a single reader thread.
+// Returns 0 on success.
+int rb_read_from_buffer(ring_buffer *buffer, char *dest, int len);
+
+#endif