src/dictionary.c

   1 #ifdef HAVE_CONFIG_H
   2 #include <config.h>
   3 #endif
   4 #include <pthread.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7
   8 #include "avl.h"
   9 #include "common.h"
  10 #include "log.h"
  11
  12 #include "dictionary.h"
  13
  14 // ----------------------------------------------------------------------------
  15 // name_value index
  16
  17 static int name_value_iterator(avl *a) { if(a) {}; return 0; }
  18
  19 static int name_value_compare(void* a, void* b) {
  20         if(((NAME_VALUE *)a)->hash < ((NAME_VALUE *)b)->hash) return -1;
  21         else if(((NAME_VALUE *)a)->hash > ((NAME_VALUE *)b)->hash) return 1;
  22         else return strcmp(((NAME_VALUE *)a)->name, ((NAME_VALUE *)b)->name);
  23 }
  24
  25 #define name_value_index_add(dict, cv) avl_insert(&((dict)->values_index), (avl *)(cv))
  26 #define name_value_index_del(dict, cv) avl_remove(&((dict)->values_index), (avl *)(cv))
  27
  28 static NAME_VALUE *dictionary_name_value_index_find(DICTIONARY *dict, const char *name, uint32_t hash) {
  29         NAME_VALUE *result = NULL, tmp;
  30         tmp.hash = (hash)?hash:simple_hash(name);
  31         tmp.name = (char *)name;
  32
  33         avl_search(&(dict->values_index), (avl *)&tmp, name_value_iterator, (avl **)&result);
  34         return result;
  35 }
  36
  37 // ----------------------------------------------------------------------------
  38
  39 static NAME_VALUE *dictionary_name_value_create(DICTIONARY *dict, const char *name, void *value, size_t value_len) {
  40         debug(D_DICTIONARY, "Creating name value entry for name '%s', value '%s'.", name, value);
  41
  42         NAME_VALUE *nv = calloc(1, sizeof(NAME_VALUE));
  43         if(!nv) fatal("Cannot allocate name_value of size %z", sizeof(NAME_VALUE));
  44
  45         nv->name = strdup(name);
  46         if(!nv->name) fatal("Cannot allocate name_value.name of size %z", strlen(name));
  47         nv->hash = simple_hash(nv->name);
  48
  49         nv->value = malloc(value_len);
  50         if(!nv->value) fatal("Cannot allocate name_value.value of size %z", value_len);
  51         memcpy(nv->value, value, value_len);
  52
  53         // link it
  54         pthread_rwlock_wrlock(&dict->rwlock);
  55         nv->next = dict->values;
  56         dict->values = nv;
  57         pthread_rwlock_unlock(&dict->rwlock);
  58
  59         // index it
  60         name_value_index_add(dict, nv);
  61
  62         return nv;
  63 }
  64
  65 static void dictionary_name_value_destroy(DICTIONARY *dict, NAME_VALUE *nv) {
  66         debug(D_DICTIONARY, "Destroying name value entry for name '%s'.", nv->name);
  67
  68         pthread_rwlock_wrlock(&dict->rwlock);
  69         if(dict->values == nv) dict->values = nv->next;
  70         else {
  71                 NAME_VALUE *n = dict->values;
  72                 while(n && n->next && n->next != nv) nv = nv->next;
  73                 if(!n || n->next != nv) fatal("Cannot find name_value with name '%s' in dictionary.", nv->name);
  74                 n->next = nv->next;
  75                 nv->next = NULL;
  76         }
  77         pthread_rwlock_unlock(&dict->rwlock);
  78
  79         free(nv->value);
  80         free(nv);
  81 }
  82
  83 // ----------------------------------------------------------------------------
  84
  85 DICTIONARY *dictionary_create(void) {
  86         debug(D_DICTIONARY, "Creating dictionary.");
  87
  88         DICTIONARY *dict = calloc(1, sizeof(DICTIONARY));
  89         if(!dict) fatal("Cannot allocate DICTIONARY");
  90
  91         dict->values_index.compar = name_value_compare;
  92         pthread_rwlock_init(&dict->rwlock, NULL);
  93
  94         return dict;
  95 }
  96
  97 void dictionary_destroy(DICTIONARY *dict) {
  98         debug(D_DICTIONARY, "Destroying dictionary.");
  99
 100         pthread_rwlock_wrlock(&dict->rwlock);
 101         while(dict->values) dictionary_name_value_destroy(dict, dict->values);
 102         pthread_rwlock_unlock(&dict->rwlock);
 103
 104         free(dict);
 105 }
 106
 107 // ----------------------------------------------------------------------------
 108
 109 void *dictionary_set(DICTIONARY *dict, const char *name, void *value, size_t value_len) {
 110         debug(D_DICTIONARY, "SET dictionary entry with name '%s'.", name);
 111
 112         pthread_rwlock_rdlock(&dict->rwlock);
 113         NAME_VALUE *nv = dictionary_name_value_index_find(dict, name, 0);
 114         pthread_rwlock_unlock(&dict->rwlock);
 115         if(!nv) {
 116                 debug(D_DICTIONARY, "Dictionary entry with name '%s' not found. Creating a new one.", name);
 117                 nv = dictionary_name_value_create(dict, name, value, value_len);
 118                 if(!nv) fatal("Cannot create name_value.");
 119                 return nv->value;
 120         }
 121         else {
 122                 debug(D_DICTIONARY, "Dictionary entry with name '%s' found. Changing its value.", name);
 123                 pthread_rwlock_wrlock(&dict->rwlock);
 124                 void *old = nv->value;
 125                 nv->value = malloc(value_len);
 126                 if(!nv->value) fatal("Cannot allocate value of size %z", value_len);
 127                 memcpy(nv->value, value, value_len);
 128                 pthread_rwlock_unlock(&dict->rwlock);
 129                 free(old);
 130         }
 131
 132         return nv->value;
 133 }
 134
 135 void *dictionary_get(DICTIONARY *dict, const char *name) {
 136         debug(D_DICTIONARY, "GET dictionary entry with name '%s'.", name);
 137
 138         pthread_rwlock_rdlock(&dict->rwlock);
 139         NAME_VALUE *nv = dictionary_name_value_index_find(dict, name, 0);
 140         pthread_rwlock_unlock(&dict->rwlock);
 141         if(!nv) {
 142                 debug(D_DICTIONARY, "Not found dictionary entry with name '%s'.", name);
 143                 return NULL;
 144         }
 145
 146         debug(D_DICTIONARY, "Found dictionary entry with name '%s'.", name);
 147         return nv->value;
 148 }