unbound/services/modstack.h

   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
  44 struct module_func_block;
  45 struct module_env;
  46
  47 /**
  48  * Stack of modules.
  49  */
  50 struct 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  */
  61 void 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  */
  69 int 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  */
  77 struct 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  */
  83 const 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  */
  95 int 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  */
 103 void 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  */
 111 int modstack_find(struct module_stack* stack, const char* name);
 112
 113 #endif /* SERVICES_MODSTACK_H */