/src/yolk-config_file_parser.ads
Ada | 122 lines | 35 code | 15 blank | 72 comment | 0 complexity | 16907aff824240eb7a0d4f8b9b452c3a MD5 | raw file
1------------------------------------------------------------------------------- 2-- -- 3-- Copyright (C) 2010-, Thomas Løcke -- 4-- -- 5-- This library is free software; you can redistribute it and/or modify -- 6-- it under terms of the GNU General Public License as published by the -- 7-- Free Software Foundation; either version 3, or (at your option) any -- 8-- later version. This library is distributed in the hope that it will be -- 9-- useful, but WITHOUT ANY WARRANTY; without even the implied warranty of -- 10-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. -- 11-- -- 12-- As a special exception under Section 7 of GPL version 3, you are -- 13-- granted additional permissions described in the GCC Runtime Library -- 14-- Exception, version 3.1, as published by the Free Software Foundation. -- 15-- -- 16-- You should have received a copy of the GNU General Public License and -- 17-- a copy of the GCC Runtime Library Exception along with this program; -- 18-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 19-- <http://www.gnu.org/licenses/>. -- 20-- -- 21------------------------------------------------------------------------------- 22 23-- This package provides simple access to configuration files. 24-- The format is: 25-- KEY VALUE 26-- 27-- Comments are prefixed with a # or a -- 28-- 29-- # This is a comment 30-- -- This is also a comment 31-- 32-- Blank lines and comments are ignored and so is pre-/postfixed whitespace, 33-- so this: 34-- 35-- [lots of whitespace]KEY[lots of whitespace]VALUE[lots of whitespace] 36-- 37-- is treated as: 38-- 39-- KEY VALUE 40-- 41-- Values containing whitespace, eg. full sentences and similar, are returned 42-- as is. It is not necessary to quote such values, so this: 43-- 44-- KEY some value with whitespace 45-- 46-- is perfectly valid, and will, when calling Get (KEY), return: 47-- 48-- some value with whitespace 49-- 50-- If VALUE is True or False (case-insensitive), then the KEY can be returned 51-- as both a String or as a Boolean. 52-- 53-- Trying to convert VALUE to an incompatible type, e.g. a Float to a Boolean 54-- will raise the Conversion_Error exception. It will NOT return some dummy 55-- value. 56-- 57-- To clear a default value, simply add the key to the configuration file, 58-- with no value set. Conversely, you must omit (or comment) keys for which 59-- you want to use the default value. 60 61with Ada.Strings.Unbounded; 62 63generic 64 use Ada.Strings.Unbounded; 65 66 type Key_Type is (<>); 67 type Defaults_Array_Type is array (Key_Type) of Unbounded_String; 68 Defaults : in Defaults_Array_Type; 69 Config_File : in String; 70 71package Yolk.Config_File_Parser is 72 73 Unknown_Key : exception; 74 -- Is raised when an unknown KEY has been found in the config file. 75 Cannot_Open_Config_File : exception; 76 -- Is raised when the given config file cannot be opened, eg. due to bad 77 -- path. 78 Conversion_Error : exception; 79 -- Is raised when a value cannot be converted to a specific type. 80 81 function Get 82 (Key : in Key_Type) 83 return Boolean; 84 85 function Get 86 (Key : in Key_Type) 87 return Duration; 88 89 function Get 90 (Key : in Key_Type) 91 return Float; 92 93 function Get 94 (Key : in Key_Type) 95 return Integer; 96 97 function Get 98 (Key : in Key_Type) 99 return String; 100 101 function Get 102 (Key : in Key_Type) 103 return Unbounded_String; 104 -- Get the VALUE for Key and convert it to target type. 105 -- Exceptions: 106 -- Conversion_Error 107 108 function Has_Non_Empty_Value 109 (Key : in Key_Type) 110 return Boolean; 111 -- Return True if Key is _not_ a Null_Unbounded_String. 112 113 procedure Load_File 114 (Config_File : in String); 115 -- Load the config file Config_File. This can be done over and over as many 116 -- times as necessary. The values from the latest file overwrites the 117 -- previous values. 118 -- Exceptions: 119 -- Cannot_Open_Ini_File 120 -- Unknown_Key 121 122end Yolk.Config_File_Parser;