Joshua Wise's Git repositories - netwatch.git/blob

1 /*

4 *

5 * Redistribution and use in source and binary forms, with or without modification,

6 * are permitted provided that the following conditions are met:

7 *

8 * 1. Redistributions of source code must retain the above copyright notice,

9 * this list of conditions and the following disclaimer.

10 * 2. Redistributions in binary form must reproduce the above copyright notice,

11 * this list of conditions and the following disclaimer in the documentation

12 * and/or other materials provided with the distribution.

13 * 3. The name of the author may not be used to endorse or promote products

14 * derived from this software without specific prior written permission.

15 *

16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED

17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT

19 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT

21 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING

24 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY

25 * OF SUCH DAMAGE.

26 *

27 * This file is part of the lwIP TCP/IP stack.

28 *

29 * Author: Adam Dunkels <adam@sics.se>

30 *

31 */

33 #ifndef __LWIP_PBUF_H__

34 #define __LWIP_PBUF_H__

36 #include "lwip/opt.h"

37 #include "lwip/err.h"

39 #ifdef __cplusplus

40 extern "C" {

41 #endif

43 #define PBUF_TRANSPORT_HLEN 20

44 #define PBUF_IP_HLEN 20

46 typedef enum {

47 PBUF_TRANSPORT,

48 PBUF_IP,

49 PBUF_LINK,

50 PBUF_RAW

51 } pbuf_layer;

53 typedef enum {

54 PBUF_RAM, /* pbuf data is stored in RAM */

55 PBUF_ROM, /* pbuf data is stored in ROM */

56 PBUF_REF, /* pbuf comes from the pbuf pool */

57 PBUF_POOL /* pbuf payload refers to RAM */

58 } pbuf_type;

61 /** indicates this packet's data should be immediately passed to the application */

62 #define PBUF_FLAG_PUSH 0x01U

64 struct pbuf {

65 /** next pbuf in singly linked pbuf chain */

66 struct pbuf *next;

68 /** pointer to the actual data in the buffer */

69 void *payload;

71 /**

72 * total length of this buffer and all next buffers in chain

73 * belonging to the same packet.

74 *

75 * For non-queue packet chains this is the invariant:

76 * p->tot_len == p->len + (p->next? p->next->tot_len: 0)

77 */

78 u16_t tot_len;

80 /** length of this buffer */

81 u16_t len;

83 /** pbuf_type as u8_t instead of enum to save space */

84 u8_t /*pbuf_type*/ type;

86 /** misc flags */

87 u8_t flags;

89 /**

90 * the reference count always equals the number of pointers

91 * that refer to this pbuf. This can be pointers from an application,

92 * the stack itself, or pbuf->next pointers from a chain.

93 */

94 u16_t ref;

96 };

98 /* Initializes the pbuf module. This call is empty for now, but may not be in future. */

99 #define pbuf_init()

100

101 struct pbuf *pbuf_alloc(pbuf_layer l, u16_t size, pbuf_type type);

102 void pbuf_realloc(struct pbuf *p, u16_t size);

103 u8_t pbuf_header(struct pbuf *p, s16_t header_size);

104 void pbuf_ref(struct pbuf *p);

105 void pbuf_ref_chain(struct pbuf *p);

106 u8_t pbuf_free(struct pbuf *p);

107 u8_t pbuf_clen(struct pbuf *p);

108 void pbuf_cat(struct pbuf *head, struct pbuf *tail);

109 void pbuf_chain(struct pbuf *head, struct pbuf *tail);

110 struct pbuf *pbuf_dechain(struct pbuf *p);

111 err_t pbuf_copy(struct pbuf *p_to, struct pbuf *p_from);

112 u16_t pbuf_copy_partial(struct pbuf *p, void *dataptr, u16_t len, u16_t offset);

113

114 #ifdef __cplusplus

115 }

116 #endif

117

118 #endif /* __LWIP_PBUF_H__ */