recvbuff.h revision 182007 
1#if !defined __recvbuff_h
2#define __recvbuff_h
3
4#ifdef HAVE_CONFIG_H
5# include <config.h>
6#endif
7
8#include "ntp.h"
9#include "ntp_fp.h"
10#include "ntp_types.h"
11
12#include <isc/list.h>
13#include <isc/result.h>
14
15/*
16 * recvbuf memory management
17 */
18#define RECV_INIT	10	/* 10 buffers initially */
19#define RECV_LOWAT	3	/* when we're down to three buffers get more */
20#define RECV_INC	5	/* get 5 more at a time */
21#define RECV_TOOMANY	40	/* this is way too many buffers */
22
23#if defined HAVE_IO_COMPLETION_PORT
24# include "ntp_iocompletionport.h"
25#include "ntp_timer.h"
26
27# define RECV_BLOCK_IO()	EnterCriticalSection(&RecvCritSection)
28# define RECV_UNBLOCK_IO()	LeaveCriticalSection(&RecvCritSection)
29
30/*  Return the event which is set when items are added to the full list
31 */
32extern HANDLE	get_recv_buff_event P((void));
33#else
34# define RECV_BLOCK_IO()
35# define RECV_UNBLOCK_IO()
36#endif
37
38
39/*
40 * Format of a recvbuf.  These are used by the asynchronous receive
41 * routine to store incoming packets and related information.
42 */
43
44/*
45 *  the maximum length NTP packet contains the NTP header, one Autokey
46 *  request, one Autokey response and the MAC. Assuming certificates don't
47 *  get too big, the maximum packet length is set arbitrarily at 1000.
48 */
49#define	RX_BUFF_SIZE	1000		/* hail Mary */
50
51
52typedef struct recvbuf recvbuf_t;
53
54struct recvbuf {
55	ISC_LINK(recvbuf_t)	link;
56	union {
57		struct sockaddr_storage X_recv_srcadr;
58		caddr_t X_recv_srcclock;
59		struct peer *X_recv_peer;
60	} X_from_where;
61#define recv_srcadr	X_from_where.X_recv_srcadr
62#define	recv_srcclock	X_from_where.X_recv_srcclock
63#define recv_peer	X_from_where.X_recv_peer
64#if defined HAVE_IO_COMPLETION_PORT
65	WSABUF		wsabuff;
66#else
67	struct sockaddr_storage srcadr;	/* where packet came from */
68#endif
69	int src_addr_len;		/* source address length */
70	struct interface *dstadr;	/* interface datagram arrived thru */
71	SOCKET	fd;			/* fd on which it was received */
72	int msg_flags;			/* Flags received about the packet */
73	l_fp recv_time;			/* time of arrival */
74	void (*receiver) P((struct recvbuf *)); /* routine to receive buffer */
75	int recv_length;		/* number of octets received */
76	union {
77		struct pkt X_recv_pkt;
78		u_char X_recv_buffer[RX_BUFF_SIZE];
79	} recv_space;
80	int used;
81#define	recv_pkt	recv_space.X_recv_pkt
82#define	recv_buffer	recv_space.X_recv_buffer
83};
84
85extern	void	init_recvbuff	P((int));
86
87/* freerecvbuf - make a single recvbuf available for reuse
88 */
89extern	void	freerecvbuf P((struct recvbuf *));
90
91/*  Get a free buffer (typically used so an async
92 *  read can directly place data into the buffer
93 *
94 *  The buffer is removed from the free list. Make sure
95 *  you put it back with freerecvbuf() or
96 */
97extern	struct recvbuf *get_free_recv_buffer P((void)); /* signal safe - no malloc */
98extern	struct recvbuf *get_free_recv_buffer_alloc P((void)); /* signal unsafe - may malloc */
99
100/*   Add a buffer to the full list
101 */
102extern	void	add_full_recv_buffer	 P((struct recvbuf *));
103
104/*extern	void	process_recv_buffers	 P((void)); */
105
106/* number of recvbufs on freelist */
107extern u_long free_recvbuffs P((void));
108extern u_long full_recvbuffs P((void));
109extern u_long total_recvbuffs P((void));
110extern u_long lowater_additions P((void));
111
112/*  Returns the next buffer in the full list.
113 *
114 */
115extern	struct recvbuf *get_full_recv_buffer P((void));
116
117/*
118 * Checks to see if there are buffers to process
119 */
120extern isc_boolean_t has_full_recv_buffer P((void));
121
122#endif /* defined __recvbuff_h */
123
124