src/lwes_event_type_db.h

   1 /*======================================================================*
   2  * Copyright (C) 2008 Light Weight Event System                         *
   3  * All rights reserved.                                                 *
   4  *                                                                      *
   5  * This program is free software; you can redistribute it and/or modify *
   6  * it under the terms of the GNU General Public License as published by *
   7  * the Free Software Foundation; either version 2 of the License, or    *
   8  * (at your option) any later version.                                  *
   9  *                                                                      *
  10  * This program is distributed in the hope that it will be useful,      *
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of       *
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
  13  * GNU General Public License for more details.                         *
  14  *                                                                      *
  15  * You should have received a copy of the GNU General Public License    *
  16  * along with this program; if not, write to the Free Software          *
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor,                   *
  18  * Boston, MA 02110-1301 USA.                                           *
  19  *======================================================================*/
  20 #ifndef __LWES_EVENT_TYPE_DB
  21 #define __LWES_EVENT_TYPE_DB
  22
  23 #include "lwes_types.h"
  24
  25 #include <stdio.h>   /* for FILENAME_MAX */
  26 #include <stdlib.h>  /* for malloc */
  27 #include <string.h>
  28
  29 #ifdef __cplusplus
  30 extern "C" {
  31 #endif
  32
  33 /*! \file lwes_event_type_db.h
  34  *  \brief Functions for an event specification file database
  35  *
  36  *  This is used in cases where you want to restrict the events allowed
  37  *  to be emitted or listened to to a particular esf file
  38  */
  39
  40 /*! \struct lwes_event_type_db_attribute lwes_event_type_db.h
  41  *  \brief The attributes stored in the database
  42  */
  43 struct lwes_event_type_db_attribute
  44 {
  45   /*! An event */
  46   struct lwes_event *event;
  47 };
  48
  49 /*! \struct lwes_event_type_db lwes_event_type_db.h
  50  *  \brief The data base itself
  51  */
  52 struct lwes_event_type_db
  53 {
  54   /*! holds the file name which describes the database (aka, the esf file) */
  55   char esf_filename[FILENAME_MAX];
  56   /*! holds a hash of event descriptions by the event name
  57       for events which are described in the esf file */
  58   struct lwes_hash *events;
  59 };
  60
  61 /*! \brief Creates the memory for the event_type_db.
  62  *
  63  *  This creates memory which should be freed with lwes_event_type_db_destroy
  64  *
  65  *  \param[in] filename the path to the file containing the esf description
  66  *
  67  *  \see lwes_event_type_db_destroy
  68  *
  69  *  \return the newly created db on success, NULL on failure
  70  */
  71 struct lwes_event_type_db *
  72 lwes_event_type_db_create
  73   (const char *filename);
  74
  75 /*! \brief Cleanup the memory for the event_type_db.
  76  *
  77  *  This frees the memory created by lwes_event_type_db_create.
  78  *
  79  *  \param[in] db the db to free
  80  *
  81  *  \return 0 on success, a negative number on failure
  82  */
  83 int
  84 lwes_event_type_db_destroy
  85   (struct lwes_event_type_db *db);
  86
  87 /*! \brief Add an an event name to the database
  88  *
  89  * \param[in] db the db to add the event name to
  90  * \param[in] event_name the name of an event
  91  *
  92  * \return 0 if the add is successful, a negative number on failure
  93  */
  94 int
  95 lwes_event_type_db_add_event
  96   (struct lwes_event_type_db *db,
  97    LWES_SHORT_STRING event_name);
  98
  99 /*! \brief Add an attribute name to an event name of the database
 100  *
 101  * \param[in] db the db to add the attr_name into
 102  * \param[in] event_name the name of an event
 103  * \param[in] attr_name the name of an attribute
 104  * \param[in] type the type of the attribute
 105  *
 106  * \return 0 if the add is successful, a negative number on failure
 107  */
 108 int
 109 lwes_event_type_db_add_attribute
 110   (struct lwes_event_type_db *db,
 111    LWES_SHORT_STRING event_name,
 112    LWES_SHORT_STRING attr_name,
 113    LWES_SHORT_STRING type);
 114
 115 /*! \brief Check for an event in the database
 116  *
 117  *  \param[in] db the db to check for the event in
 118  *  \param[in] event_name the name of an event
 119  *
 120  *  \return 1 if the event is in the db, 0 if it is not
 121  */
 122 int
 123 lwes_event_type_db_check_for_event
 124   (struct lwes_event_type_db *db,
 125    LWES_SHORT_STRING event_name);
 126
 127 /*! \brief Check for an attribute in an event in the database
 128  *
 129  *  \param[in] db the db to check
 130  *  \param[in] attr_name the attribute name to check for
 131  *  \param[in] event_name the event name to check in
 132  *
 133  *  \return 1 if the attribute is in the event in the db, 0 if it is not
 134  */
 135 int
 136 lwes_event_type_db_check_for_attribute
 137   (struct lwes_event_type_db *db,
 138    LWES_CONST_SHORT_STRING attr_name,
 139    LWES_CONST_SHORT_STRING event_name);
 140
 141 /*! \brief Check the type of an attribute in an event in the db
 142  *
 143  *  \param[in] db the db to check
 144  *  \param[in] type_value the type to check against
 145  *  \param[in] attr_name the attribute name to check for
 146  *  \param[in] event_name the event name to check in
 147  *
 148  *  \return 1 if the attribute in the event in the db is of the asked for type,
 149  *          0 if it is not of the specified type
 150  */
 151 int
 152 lwes_event_type_db_check_for_type
 153   (struct lwes_event_type_db *db,
 154    LWES_BYTE type_value,
 155    LWES_CONST_SHORT_STRING attr_name,
 156    LWES_CONST_SHORT_STRING event_name);
 157
 158 #ifdef __cplusplus
 159 }
 160 #endif
 161
 162 #endif /* __LWES_EVENT_TYPE_DB */