ConfigFile.h

00001 /**
00002  * ConfigFile.cpp
00003  * Simple Config file reader class
00004  *
00005  * Copyright (c) 2011 Peter Brier
00006  *
00007  *   This file is part of the LaOS project (see: http://wiki.protospace.nl/index.php/LaOS)
00008  *
00009  *   LaOS is free software: you can redistribute it and/or modify
00010  *   it under the terms of the GNU General Public License as published by
00011  *   the Free Software Foundation, either version 3 of the License, or
00012  *   (at your option) any later version.
00013  *
00014  *   LaOS is distributed in the hope that it will be useful,
00015  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
00016  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00017  *   GNU General Public License for more details.
00018  *
00019  *   You should have received a copy of the GNU General Public License
00020  *   along with LaOS.  If not, see <http://www.gnu.org/licenses/>.
00021  *
00022  * Reads a setting, based on the key. (case sensitive)
00023  * If the key is not found, the default value is returned.
00024  *
00025  * Simple, not (time) efficient. For every request, the complete file is reset and read again
00026  *
00027  @code 
00028  file format
00029  
00030  ; comment
00031  key value [newline || comment]
00032 
00033  For example:
00034  
00035  ; This is a test config file
00036  ip 192.168.1.1
00037  port 1234 ; the key is "port" the value is "1234". The rest is comment
00038  ; EOF
00039  @endcode
00040  */
00041 #ifndef _CONFIG_FILE_H_
00042 #define _CONFIG_FILE_H_
00043 
00044 #include "global.h"
00045 #include "laosfilesystem.h"
00046 
00047     /** Simple config file object
00048       * Only supports reading config files. Tries to limit memory usage.
00049       * Note: the file handle is kept open during the lifetime of this object.
00050       * To close the file: destroy this ConfigFile object! A simple way is to enclose the creation
00051       * of this object inside a code block
00052       * Example:
00053       * @code 
00054       * char ip[16];
00055       * int port;
00056       * {
00057       *   ConfigFile cfg("/local/config.txt");
00058       *   cfg.Value("ip", ip, sizeof(ip), "192.168.1.10");
00059       *   cfg.Value("port", &port, 80);
00060       * }
00061       * @endcode
00062       */
00063 class ConfigFile {
00064 public:
00065     /** Make new ConfigFile object. Open config file.
00066       * Note: the file handle is kept open during the lifetime of this object.
00067       * To close the file: destroy this ConfigFile object!
00068       * @param file Filename of the configuration file.
00069       */
00070     ConfigFile(char *name);
00071 
00072     ~ConfigFile();
00073 
00074 /** Read value. If file is not open, or key does not exist: copy default value (return false)
00075   * @param key name of the key in the file
00076   * @param value pointer to buffer that receives the value
00077   * @param maxlen the maximum length of the value. If the actual value is longer, it is truncated
00078   * @param def Default value. If the key is not found in the file, this value is copied. 
00079   * @return "true" if the key is found "false" is key is not found (default value is returned)
00080   */ 
00081     bool Value(char *key, char *value,  size_t maxlen, char *def);
00082 
00083 /** Read Integer value. If file is not open, or key does not exist: copy default value (return false)
00084   * @param key name of the key in the file
00085   * @param value pointer to integer that receives the value
00086   * @param def Default value. If the key is not found in the file, this value is copied. 
00087   * @return "true" if the key is found "false" is key is not found (default value is returned)
00088   */ 
00089     bool Value(char *key, int *value, int def);
00090     
00091   /** See if file was present
00092   * @return "true" if file is open, "false" file is not found 
00093   */ 
00094   bool IsOpen(void) { return fp != NULL; }
00095   
00096 private:
00097     FILE *fp;
00098 
00099 };
00100 
00101 
00102 #endif