modstack.h revision 356345 
1/*
2 * services/modstack.h - stack of modules
3 *
4 * Copyright (c) 2007, NLnet Labs. All rights reserved.
5 *
6 * This software is open source.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * Redistributions of source code must retain the above copyright notice,
13 * this list of conditions and the following disclaimer.
14 *
15 * Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 *
19 * Neither the name of the NLNET LABS nor the names of its contributors may
20 * be used to endorse or promote products derived from this software without
21 * specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36/**
37 * \file
38 *
39 * This file contains functions to help maintain a stack of modules.
40 */
41
42#ifndef SERVICES_MODSTACK_H
43#define SERVICES_MODSTACK_H
44struct module_func_block;
45struct module_env;
46
47/**
48 * Stack of modules.
49 */
50struct module_stack {
51	/** the number of modules */
52	int num;
53	/** the module callbacks, array of num_modules length (ref only) */
54	struct module_func_block** mod;
55};
56
57/**
58 * Init a stack of modules
59 * @param stack: initialised as empty.
60 */
61void modstack_init(struct module_stack* stack);
62
63/**
64 * Read config file module settings and set up the modfunc block
65 * @param stack: the stack of modules (empty before call).
66 * @param module_conf: string what modules to insert.
67 * @return false on error
68 */
69int modstack_config(struct module_stack* stack, const char* module_conf);
70
71/**
72 * Get funcblock for module name
73 * @param str: string with module name. Advanced to next value on success.
74 *	The string is assumed whitespace separated list of module names.
75 * @return funcblock or NULL on error.
76 */
77struct module_func_block* module_factory(const char** str);
78
79/**
80 * Get list of modules available.
81 * @return list of modules available. Static strings, ends with NULL.
82 */
83const char** module_list_avail(void);
84
85/**
86 * Setup modules. Assigns ids and calls module_init.
87 * @param stack: if not empty beforehand, it will be desetup()ed.
88 *	It is then modstack_configged().
89 * @param module_conf: string what modules to insert.
90 * @param env: module environment which is inited by the modules.
91 *	environment should have a superalloc, cfg,
92 *	env.need_to_validate is set by the modules.
93 * @return on false a module init failed.
94 */
95int modstack_setup(struct module_stack* stack, const char* module_conf,
96	struct module_env* env);
97
98/**
99 * Desetup the modules, deinit, delete.
100 * @param stack: made empty.
101 * @param env: module env for module deinit() calls.
102 */
103void modstack_desetup(struct module_stack* stack, struct module_env* env);
104
105/**
106 * Find index of module by name.
107 * @param stack: to look in
108 * @param name: the name to look for
109 * @return -1 on failure, otherwise index number.
110 */
111int modstack_find(struct module_stack* stack, const char* name);
112
113/** fetch memory for a module by name, returns 0 if module not there */
114size_t mod_get_mem(struct module_env* env, const char* name);
115
116#endif /* SERVICES_MODSTACK_H */
117