a759efa6 |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: bres.h,v 1.1 1999/10/04 21:40:42 mdw Exp $ |
4 | * |
5 | * Background reverse name resolution |
6 | * |
7 | * (c) 1999 Straylight/Edgeware |
8 | */ |
9 | |
10 | /*----- Licensing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of the mLib utilities library. |
13 | * |
14 | * mLib is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU Library General Public License as |
16 | * published by the Free Software Foundation; either version 2 of the |
17 | * License, or (at your option) any later version. |
18 | * |
19 | * mLib is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU Library General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU Library General Public |
25 | * License along with mLib; if not, write to the Free |
26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
27 | * MA 02111-1307, USA. |
28 | */ |
29 | |
30 | /*----- Revision history --------------------------------------------------* |
31 | * |
32 | * $Log: bres.h,v $ |
33 | * Revision 1.1 1999/10/04 21:40:42 mdw |
34 | * Added background resolver from `fw'. |
35 | * |
36 | */ |
37 | |
38 | #ifndef RES_H |
39 | #define RES_H |
40 | |
41 | #ifdef __cplusplus |
42 | extern "C" { |
43 | #endif |
44 | |
45 | /*----- Header files ------------------------------------------------------*/ |
46 | |
47 | #include <sys/types.h> |
48 | |
49 | #include <sys/socket.h> |
50 | #include <netinet/in.h> |
51 | #include <arpa/inet.h> |
52 | #include <netdb.h> |
53 | |
54 | #include <mLib/sel.h> |
55 | #include <mLib/selbuf.h> |
56 | |
57 | /*----- Data structures ---------------------------------------------------*/ |
58 | |
59 | /* --- Client allocated request block --- */ |
60 | |
61 | typedef struct bres_client { |
62 | struct bres_client *next, *prev; /* Queue of waiting resolve jobs */ |
63 | struct bres_server *rs; /* Pointer to attached server */ |
64 | int q; /* Query type (name or address) */ |
65 | union { |
66 | struct in_addr addr; /* Address to resolve */ |
67 | char *name; /* Name to resolve */ |
68 | } u; |
69 | void (*func)(struct hostent */*h*/, void */*p*/); /* Handler function */ |
70 | void *p; /* Argument for handler function */ |
71 | } bres_client; |
72 | |
73 | /* --- Server maintained resolver blocks --- */ |
74 | |
75 | typedef struct bres_server { |
76 | struct bres_server *next, *prev; /* Doubly-linked list of servers */ |
77 | pid_t kid; /* Process id of server process */ |
78 | int fd; /* File descriptors */ |
79 | struct bres_client *rc; /* Pointer to attached client */ |
80 | sel_timer t; /* Timeout for idle servers */ |
81 | sel_file f; /* Read selector for server */ |
82 | } bres_server; |
83 | |
84 | /*----- Functions provided ------------------------------------------------*/ |
85 | |
86 | /* --- @bres_abort@ --- * |
87 | * |
88 | * Arguments: @bres_client *rc@ = pointer to client block |
89 | * |
90 | * Returns: --- |
91 | * |
92 | * Use: Removes a queued job. |
93 | */ |
94 | |
95 | extern void bres_abort(bres_client */*rc*/); |
96 | |
97 | /* --- @bres_byaddr@ --- * |
98 | * |
99 | * Arguments: @bres_client *rc@ = pointer to client block |
100 | * @struct in_addr addr@ = address to resolve |
101 | * @void (*func)(struct hostent *h, void *p)@ = handler function |
102 | * @void *p@ = argument for handler function |
103 | * |
104 | * Returns: --- |
105 | * |
106 | * Use: Adds an address lookup job to the queue. The job will be |
107 | * processed when there's a spare resolver process to deal with |
108 | * it. |
109 | */ |
110 | |
111 | extern void bres_byaddr(bres_client */*rc*/, struct in_addr /*addr*/, |
112 | void (*/*func*/)(struct hostent */*h*/, void */*p*/), |
113 | void */*p*/); |
114 | |
115 | /* --- @bres_byname@ --- * |
116 | * |
117 | * Arguments: @bres_client *rc@ = pointer to client block |
118 | * @const char *name@ = name to resolve |
119 | * @void (*func)(struct hostent *h, void *p)@ = handler function |
120 | * @void *p@ = argument for handler function |
121 | * |
122 | * Returns: --- |
123 | * |
124 | * Use: Adds a name lookup job to the queue. The job will be |
125 | * processed when there's a spare resolver process to deal with |
126 | * it. |
127 | */ |
128 | |
129 | extern void bres_byname(bres_client */*rc*/, const char */*name*/, |
130 | void (*/*func*/)(struct hostent */*h*/, void */*p*/), |
131 | void */*p*/); |
132 | |
133 | /* --- @bres_exec@ --- * |
134 | * |
135 | * Arguments: @const char *file@ = file containing server code or null |
136 | * |
137 | * Returns: --- |
138 | * |
139 | * Use: Makes `bres' use a standalone server rather than copies of |
140 | * the current process. This can reduce memory consumption for |
141 | * large processes, at the expense of startup time (which |
142 | * shouldn't be too bad anyway, because of the resolver design). |
143 | * If the filename is null, a default set up at install time is |
144 | * used. It's probably a good idea to leave it alone. |
145 | */ |
146 | |
147 | extern void bres_exec(const char */*file*/); |
148 | |
149 | /* --- @bres_init@ --- * |
150 | * |
151 | * Arguments: @sel_state *s@ = pointer to select multiplexor |
152 | * |
153 | * Returns: --- |
154 | * |
155 | * Use: Initializes the background resolver for use. |
156 | */ |
157 | |
158 | extern void bres_init(sel_state */*s*/); |
159 | |
160 | /*----- That's all, folks -------------------------------------------------*/ |
161 | |
162 | #ifdef __cplusplus |
163 | } |
164 | #endif |
165 | |
166 | #endif |