1 /*
2  * Copyright (C) 2004-2008  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 2000, 2001  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* $Id: context.h,v 1.23 2008/12/17 23:47:58 tbox Exp $ */
19 
20 #ifndef LWRES_CONTEXT_H
21 #define LWRES_CONTEXT_H 1
22 
23 /*! \file lwres/context.h */
24 
25 #include <stddef.h>
26 
27 #include <lwres/lang.h>
28 #include <lwres/int.h>
29 #include <lwres/result.h>
30 
31 /*!
32  * Used to set various options such as timeout, authentication, etc
33  */
34 typedef struct lwres_context lwres_context_t;
35 
36 LWRES_LANG_BEGINDECLS
37 
38 typedef void *(*lwres_malloc_t)(void *arg, size_t length);
39 typedef void (*lwres_free_t)(void *arg, void *mem, size_t length);
40 
41 /*
42  * XXXMLG
43  *
44  * Make the server reload /etc/resolv.conf periodically.
45  *
46  * Make the server do sortlist/searchlist.
47  *
48  * Client side can disable the search/sortlist processing.
49  *
50  * Use an array of addresses/masks and searchlist for client-side, and
51  * if added to the client disable the processing on the server.
52  *
53  * Share /etc/resolv.conf data between contexts.
54  */
55 
56 /*!
57  * _SERVERMODE
58  *	Don't allocate and connect a socket to the server, since the
59  *	caller _is_ a server.
60  *
61  * _USEIPV4, _USEIPV6
62  *	Use IPv4 and IPv6 transactions with remote servers, respectively.
63  *	For backward compatibility, regard both flags as being set when both
64  *	are cleared.
65  */
66 #define LWRES_CONTEXT_SERVERMODE	0x00000001U
67 #define LWRES_CONTEXT_USEIPV4		0x00000002U
68 #define LWRES_CONTEXT_USEIPV6		0x00000004U
69 
70 lwres_result_t
71 lwres_context_create(lwres_context_t **contextp, void *arg,
72 		     lwres_malloc_t malloc_function,
73 		     lwres_free_t free_function,
74 		     unsigned int flags);
75 /**<
76  * Allocate a lwres context.  This is used in all lwres calls.
77  *
78  * Memory management can be replaced here by passing in two functions.
79  * If one is non-NULL, they must both be non-NULL.  "arg" is passed to
80  * these functions.
81  *
82  * Contexts are not thread safe.  Document at the top of the file.
83  * XXXMLG
84  *
85  * If they are NULL, the standard malloc() and free() will be used.
86  *
87  *\pre	contextp != NULL && contextp == NULL.
88  *
89  *\return	Returns 0 on success, non-zero on failure.
90  */
91 
92 void
93 lwres_context_destroy(lwres_context_t **contextp);
94 /**<
95  * Frees all memory associated with a lwres context.
96  *
97  *\pre	contextp != NULL && contextp == NULL.
98  */
99 
100 lwres_uint32_t
101 lwres_context_nextserial(lwres_context_t *ctx);
102 /**<
103  * XXXMLG Document
104  */
105 
106 void
107 lwres_context_initserial(lwres_context_t *ctx, lwres_uint32_t serial);
108 
109 void
110 lwres_context_freemem(lwres_context_t *ctx, void *mem, size_t len);
111 
112 void *
113 lwres_context_allocmem(lwres_context_t *ctx, size_t len);
114 
115 int
116 lwres_context_getsocket(lwres_context_t *ctx);
117 
118 lwres_result_t
119 lwres_context_send(lwres_context_t *ctx,
120 		   void *sendbase, int sendlen);
121 
122 lwres_result_t
123 lwres_context_recv(lwres_context_t *ctx,
124 		   void *recvbase, int recvlen,
125 		   int *recvd_len);
126 
127 lwres_result_t
128 lwres_context_sendrecv(lwres_context_t *ctx,
129 		       void *sendbase, int sendlen,
130 		       void *recvbase, int recvlen,
131 		       int *recvd_len);
132 
133 LWRES_LANG_ENDDECLS
134 
135 #endif /* LWRES_CONTEXT_H */
136 
137