1 2/*-------------------------------------------------------------------------*/ 3/** 4 @file dictionary.h 5 @author N. Devillard 6 @date Aug 2000 7 @version $Revision: 1.1.1.1 $ 8 @brief Implements a dictionary for string variables. 9 10 This module implements a simple dictionary object, i.e. a list 11 of string/string associations. This object is useful to store e.g. 12 informations retrieved from a configuration file (ini files). 13*/ 14/*--------------------------------------------------------------------------*/ 15 16/* 17 $Id: dictionary.h,v 1.1.1.1 2011/06/10 09:35:00 andrew Exp $ 18 $Author: andrew $ 19 $Date: 2011/06/10 09:35:00 $ 20 $Revision: 1.1.1.1 $ 21*/ 22 23#ifndef _DICTIONARY_H_ 24#define _DICTIONARY_H_ 25 26/*--------------------------------------------------------------------------- 27 Includes 28 ---------------------------------------------------------------------------*/ 29 30#include <stdio.h> 31#include <stdlib.h> 32#include <string.h> 33#include <unistd.h> 34 35/*--------------------------------------------------------------------------- 36 New types 37 ---------------------------------------------------------------------------*/ 38 39 40/*-------------------------------------------------------------------------*/ 41/** 42 @brief Dictionary object 43 44 This object contains a list of string/string associations. Each 45 association is identified by a unique string key. Looking up values 46 in the dictionary is speeded up by the use of a (hopefully collision-free) 47 hash function. 48 */ 49/*-------------------------------------------------------------------------*/ 50typedef struct _dictionary_ { 51 int n ; /** Number of entries in dictionary */ 52 int size ; /** Storage size */ 53 char ** val ; /** List of string values */ 54 char ** key ; /** List of string keys */ 55 unsigned * hash ; /** List of hash values for keys */ 56} dictionary ; 57 58 59/*--------------------------------------------------------------------------- 60 Function prototypes 61 ---------------------------------------------------------------------------*/ 62 63/*-------------------------------------------------------------------------*/ 64/** 65 @brief Compute the hash key for a string. 66 @param key Character string to use for key. 67 @return 1 unsigned int on at least 32 bits. 68 69 This hash function has been taken from an Article in Dr Dobbs Journal. 70 This is normally a collision-free function, distributing keys evenly. 71 The key is stored anyway in the struct so that collision can be avoided 72 by comparing the key itself in last resort. 73 */ 74/*--------------------------------------------------------------------------*/ 75unsigned dictionary_hash(char * key); 76 77/*-------------------------------------------------------------------------*/ 78/** 79 @brief Create a new dictionary object. 80 @param size Optional initial size of the dictionary. 81 @return 1 newly allocated dictionary objet. 82 83 This function allocates a new dictionary object of given size and returns 84 it. If you do not know in advance (roughly) the number of entries in the 85 dictionary, give size=0. 86 */ 87/*--------------------------------------------------------------------------*/ 88dictionary * dictionary_new(int size); 89 90/*-------------------------------------------------------------------------*/ 91/** 92 @brief Delete a dictionary object 93 @param d dictionary object to deallocate. 94 @return void 95 96 Deallocate a dictionary object and all memory associated to it. 97 */ 98/*--------------------------------------------------------------------------*/ 99void dictionary_del(dictionary * vd); 100 101/*-------------------------------------------------------------------------*/ 102/** 103 @brief Get a value from a dictionary. 104 @param d dictionary object to search. 105 @param key Key to look for in the dictionary. 106 @param def Default value to return if key not found. 107 @return 1 pointer to internally allocated character string. 108 109 This function locates a key in a dictionary and returns a pointer to its 110 value, or the passed 'def' pointer if no such key can be found in 111 dictionary. The returned character pointer points to data internal to the 112 dictionary object, you should not try to free it or modify it. 113 */ 114/*--------------------------------------------------------------------------*/ 115char * dictionary_get(dictionary * d, char * key, char * def); 116 117 118/*-------------------------------------------------------------------------*/ 119/** 120 @brief Get a value from a dictionary, as a char. 121 @param d dictionary object to search. 122 @param key Key to look for in the dictionary. 123 @param def Default value for the key if not found. 124 @return char 125 126 This function locates a key in a dictionary using dictionary_get, 127 and returns the first char of the found string. 128 */ 129/*--------------------------------------------------------------------------*/ 130char dictionary_getchar(dictionary * d, char * key, char def) ; 131 132/*-------------------------------------------------------------------------*/ 133/** 134 @brief Get a value from a dictionary, as an int. 135 @param d dictionary object to search. 136 @param key Key to look for in the dictionary. 137 @param def Default value for the key if not found. 138 @return int 139 140 This function locates a key in a dictionary using dictionary_get, 141 and applies atoi on it to return an int. If the value cannot be found 142 in the dictionary, the default is returned. 143 */ 144/*--------------------------------------------------------------------------*/ 145int dictionary_getint(dictionary * d, char * key, int def); 146 147/*-------------------------------------------------------------------------*/ 148/** 149 @brief Get a value from a dictionary, as a double. 150 @param d dictionary object to search. 151 @param key Key to look for in the dictionary. 152 @param def Default value for the key if not found. 153 @return double 154 155 This function locates a key in a dictionary using dictionary_get, 156 and applies atof on it to return a double. If the value cannot be found 157 in the dictionary, the default is returned. 158 */ 159/*--------------------------------------------------------------------------*/ 160double dictionary_getdouble(dictionary * d, char * key, double def); 161 162/*-------------------------------------------------------------------------*/ 163/** 164 @brief Set a value in a dictionary. 165 @param d dictionary object to modify. 166 @param key Key to modify or add. 167 @param val Value to add. 168 @return void 169 170 If the given key is found in the dictionary, the associated value is 171 replaced by the provided one. If the key cannot be found in the 172 dictionary, it is added to it. 173 174 It is Ok to provide a NULL value for val, but NULL values for the dictionary 175 or the key are considered as errors: the function will return immediately 176 in such a case. 177 178 Notice that if you dictionary_set a variable to NULL, a call to 179 dictionary_get will return a NULL value: the variable will be found, and 180 its value (NULL) is returned. In other words, setting the variable 181 content to NULL is equivalent to deleting the variable from the 182 dictionary. It is not possible (in this implementation) to have a key in 183 the dictionary without value. 184 */ 185/*--------------------------------------------------------------------------*/ 186void dictionary_set(dictionary * vd, char * key, char * val); 187 188/*-------------------------------------------------------------------------*/ 189/** 190 @brief Delete a key in a dictionary 191 @param d dictionary object to modify. 192 @param key Key to remove. 193 @return void 194 195 This function deletes a key in a dictionary. Nothing is done if the 196 key cannot be found. 197 */ 198/*--------------------------------------------------------------------------*/ 199void dictionary_unset(dictionary * d, char * key); 200 201 202/*-------------------------------------------------------------------------*/ 203/** 204 @brief Set a key in a dictionary, providing an int. 205 @param d Dictionary to update. 206 @param key Key to modify or add 207 @param val Integer value to store (will be stored as a string). 208 @return void 209 210 This helper function calls dictionary_set() with the provided integer 211 converted to a string using %d. 212 */ 213/*--------------------------------------------------------------------------*/ 214void dictionary_setint(dictionary * d, char * key, int val); 215 216/*-------------------------------------------------------------------------*/ 217/** 218 @brief Set a key in a dictionary, providing a double. 219 @param d Dictionary to update. 220 @param key Key to modify or add 221 @param val Double value to store (will be stored as a string). 222 @return void 223 224 This helper function calls dictionary_set() with the provided double 225 converted to a string using %g. 226 */ 227/*--------------------------------------------------------------------------*/ 228void dictionary_setdouble(dictionary * d, char * key, double val); 229 230/*-------------------------------------------------------------------------*/ 231/** 232 @brief Dump a dictionary to an opened file pointer. 233 @param d Dictionary to dump 234 @param f Opened file pointer. 235 @return void 236 237 Dumps a dictionary onto an opened file pointer. Key pairs are printed out 238 as @c [Key]=[Value], one per line. It is Ok to provide stdout or stderr as 239 output file pointers. 240 */ 241/*--------------------------------------------------------------------------*/ 242void dictionary_dump(dictionary * d, FILE * out); 243 244#endif 245