project_files/frontlib/iniparser/dictionary.h
changeset 7175 038e3415100a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/project_files/frontlib/iniparser/dictionary.h	Thu Jun 07 02:45:18 2012 +0200
@@ -0,0 +1,165 @@
+
+/*-------------------------------------------------------------------------*/
+/**
+   @file    dictionary.h
+   @author  N. Devillard
+   @brief   Implements a dictionary for string variables.
+
+   This module implements a simple dictionary object, i.e. a list
+   of string/string associations. This object is useful to store e.g.
+   informations retrieved from a configuration file (ini files).
+*/
+/*--------------------------------------------------------------------------*/
+
+#ifndef _DICTIONARY_H_
+#define _DICTIONARY_H_
+
+/*---------------------------------------------------------------------------
+                                Includes
+ ---------------------------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+/*---------------------------------------------------------------------------
+                                New types
+ ---------------------------------------------------------------------------*/
+
+
+/*-------------------------------------------------------------------------*/
+/**
+  @brief    Dictionary object
+
+  This object contains a list of string/string associations. Each
+  association is identified by a unique string key. Looking up values
+  in the dictionary is speeded up by the use of a (hopefully collision-free)
+  hash function.
+ */
+/*-------------------------------------------------------------------------*/
+typedef struct _dictionary_ {
+    int             n ;     /** Number of entries in dictionary */
+    int             size ;  /** Storage size */
+    char        **  val ;   /** List of string values */
+    char        **  key ;   /** List of string keys */
+    unsigned     *  hash ;  /** List of hash values for keys */
+} dictionary ;
+
+
+/*---------------------------------------------------------------------------
+                            Function prototypes
+ ---------------------------------------------------------------------------*/
+
+/*-------------------------------------------------------------------------*/
+/**
+  @brief    Compute the hash key for a string.
+  @param    key     Character string to use for key.
+  @return   1 unsigned int on at least 32 bits.
+
+  This hash function has been taken from an Article in Dr Dobbs Journal.
+  This is normally a collision-free function, distributing keys evenly.
+  The key is stored anyway in the struct so that collision can be avoided
+  by comparing the key itself in last resort.
+ */
+/*--------------------------------------------------------------------------*/
+unsigned dictionary_hash(const char * key);
+
+/*-------------------------------------------------------------------------*/
+/**
+  @brief    Create a new dictionary object.
+  @param    size    Optional initial size of the dictionary.
+  @return   1 newly allocated dictionary objet.
+
+  This function allocates a new dictionary object of given size and returns
+  it. If you do not know in advance (roughly) the number of entries in the
+  dictionary, give size=0.
+ */
+/*--------------------------------------------------------------------------*/
+dictionary * dictionary_new(int size);
+
+/*-------------------------------------------------------------------------*/
+/**
+  @brief    Delete a dictionary object
+  @param    d   dictionary object to deallocate.
+  @return   void
+
+  Deallocate a dictionary object and all memory associated to it.
+ */
+/*--------------------------------------------------------------------------*/
+void dictionary_del(dictionary * vd);
+
+/*-------------------------------------------------------------------------*/
+/**
+  @brief    Get a value from a dictionary.
+  @param    d       dictionary object to search.
+  @param    key     Key to look for in the dictionary.
+  @param    def     Default value to return if key not found.
+  @return   1 pointer to internally allocated character string.
+
+  This function locates a key in a dictionary and returns a pointer to its
+  value, or the passed 'def' pointer if no such key can be found in
+  dictionary. The returned character pointer points to data internal to the
+  dictionary object, you should not try to free it or modify it.
+ */
+/*--------------------------------------------------------------------------*/
+char * dictionary_get(dictionary * d, const char * key, char * def);
+
+
+/*-------------------------------------------------------------------------*/
+/**
+  @brief    Set a value in a dictionary.
+  @param    d       dictionary object to modify.
+  @param    key     Key to modify or add.
+  @param    val     Value to add.
+  @return   int     0 if Ok, anything else otherwise
+
+  If the given key is found in the dictionary, the associated value is
+  replaced by the provided one. If the key cannot be found in the
+  dictionary, it is added to it.
+
+  It is Ok to provide a NULL value for val, but NULL values for the dictionary
+  or the key are considered as errors: the function will return immediately
+  in such a case.
+
+  Notice that if you dictionary_set a variable to NULL, a call to
+  dictionary_get will return a NULL value: the variable will be found, and
+  its value (NULL) is returned. In other words, setting the variable
+  content to NULL is equivalent to deleting the variable from the
+  dictionary. It is not possible (in this implementation) to have a key in
+  the dictionary without value.
+
+  This function returns non-zero in case of failure.
+ */
+/*--------------------------------------------------------------------------*/
+int dictionary_set(dictionary * vd, const char * key, const char * val);
+
+/*-------------------------------------------------------------------------*/
+/**
+  @brief    Delete a key in a dictionary
+  @param    d       dictionary object to modify.
+  @param    key     Key to remove.
+  @return   void
+
+  This function deletes a key in a dictionary. Nothing is done if the
+  key cannot be found.
+ */
+/*--------------------------------------------------------------------------*/
+void dictionary_unset(dictionary * d, const char * key);
+
+
+/*-------------------------------------------------------------------------*/
+/**
+  @brief    Dump a dictionary to an opened file pointer.
+  @param    d   Dictionary to dump
+  @param    f   Opened file pointer.
+  @return   void
+
+  Dumps a dictionary onto an opened file pointer. Key pairs are printed out
+  as @c [Key]=[Value], one per line. It is Ok to provide stdout or stderr as
+  output file pointers.
+ */
+/*--------------------------------------------------------------------------*/
+void dictionary_dump(dictionary * d, FILE * out);
+
+#endif