headers/private/kernel/util/ring_buffer.h

   1 /*
   2  * Copyright 2005, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
   3  * Distributed under the terms of the MIT License.
   4  */
   5 #ifndef RING_BUFFER_H
   6 #define RING_BUFFER_H
   7
   8
   9 #include <OS.h>
  10
  11
  12 struct iovec;
  13
  14
  15 struct ring_buffer {
  16         int32           first;
  17         int32           in;
  18         int32           size;
  19         uint8           buffer[0];
  20 };
  21
  22
  23 // flags for create_ring_buffer_etc()
  24 #define RING_BUFFER_INIT_FROM_BUFFER    0x01
  25
  26
  27 #ifdef __cplusplus
  28 extern "C" {
  29 #endif
  30
  31 struct ring_buffer *create_ring_buffer(size_t size);
  32 struct ring_buffer *create_ring_buffer_etc(void *memory, size_t size,
  33                         uint32 flags);
  34 void delete_ring_buffer(struct ring_buffer *buffer);
  35
  36 void ring_buffer_clear(struct ring_buffer *buffer);
  37 size_t ring_buffer_readable(struct ring_buffer *buffer);
  38 size_t ring_buffer_writable(struct ring_buffer *buffer);
  39 void ring_buffer_flush(struct ring_buffer *buffer, size_t bytes);
  40 size_t ring_buffer_read(struct ring_buffer *buffer, uint8 *data, ssize_t length);
  41 size_t ring_buffer_write(struct ring_buffer *buffer, const uint8 *data, ssize_t length);
  42 ssize_t ring_buffer_user_read(struct ring_buffer *buffer, uint8 *data, ssize_t length);
  43 ssize_t ring_buffer_user_write(struct ring_buffer *buffer, const uint8 *data, ssize_t length);
  44 size_t ring_buffer_peek(struct ring_buffer *buffer, size_t offset, void *data,
  45                         size_t length);
  46 int32 ring_buffer_get_vecs(struct ring_buffer *buffer, struct iovec *vecs);
  47
  48 #ifdef __cplusplus
  49 }
  50 #endif
  51
  52
  53 #endif  /* RING_BUFFER_H */