source/iniparser/src/dictionary.h

   1
   2 /*-------------------------------------------------------------------------*/
   3 /**
   4    @file    dictionary.h
   5    @author  N. Devillard
   6    @date    Aug 2000
   7    @version $Revision: 1.11 $
   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 1.11 2002/06/17 09:30:46 ndevilla Exp $
  18         $Author: ndevilla $
  19         $Date: 2002/06/17 09:30:46 $
  20         $Revision: 1.11 $
  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 /*-------------------------------------------------------------------------*/
  50 typedef 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 /*--------------------------------------------------------------------------*/
  75 unsigned 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 /*--------------------------------------------------------------------------*/
  88 dictionary * 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 /*--------------------------------------------------------------------------*/
  99 void 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 /*--------------------------------------------------------------------------*/
 115 char * 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 /*--------------------------------------------------------------------------*/
 130 char 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 /*--------------------------------------------------------------------------*/
 145 int 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 /*--------------------------------------------------------------------------*/
 160 double 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 /*--------------------------------------------------------------------------*/
 186 void 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 /*--------------------------------------------------------------------------*/
 199 void 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 /*--------------------------------------------------------------------------*/
 214 void 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 /*--------------------------------------------------------------------------*/
 228 void 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 /*--------------------------------------------------------------------------*/
 242 void dictionary_dump(dictionary * d, FILE * out);
 243
 244 #endif