libdebian-installer
Data Structures | Macros | Functions
Di_hash_table

Data Structures

struct  di_hash_table
 Hash table. More...
 
struct  di_hash_node
 Node of a hash table. More...
 

Macros

#define HASH_TABLE_RESIZE(hash_table)
 
#define HASH_TABLE_MIN_SIZE   11
 
#define HASH_TABLE_MAX_SIZE   13845163
 
#define CLAMP(x, low, high)   (((x) > (high)) ? (high) : (((x) < (low)) ? (low) : (x)))
 

Functions

di_hash_tabledi_hash_table_new (di_hash_func hash_func, di_equal_func key_equal_func)
 
di_hash_tabledi_hash_table_new_full (di_hash_func hash_func, di_equal_func key_equal_func, di_destroy_notify key_destroy_func, di_destroy_notify value_destroy_func)
 
void di_hash_table_destroy (di_hash_table *hash_table)
 
void di_hash_table_insert (di_hash_table *hash_table, void *key, void *value)
 
void * di_hash_table_lookup (di_hash_table *hash_table, const void *key)
 
void di_hash_table_foreach (di_hash_table *hash_table, di_hfunc *func, void *user_data)
 
di_ksize_t di_hash_table_size (di_hash_table *hash_table)
 
static void internal_di_hash_table_resize (di_hash_table *hash_table)
 
static di_hash_node ** internal_di_hash_table_lookup_node (di_hash_table *hash_table, const void *key)
 
static di_hash_nodeinternal_di_hash_node_new (di_hash_table *hash_table, void *key, void *value)
 
static void internal_di_hash_node_destroy (di_hash_node *hash_node, di_destroy_notify key_destroy_func, di_destroy_notify value_destroy_func) __attribute__((unused))
 
static void internal_di_hash_nodes_destroy (di_hash_node *hash_node, di_destroy_notify key_destroy_func, di_destroy_notify value_destroy_func)
 

Detailed Description

Macro Definition Documentation

◆ CLAMP

#define CLAMP (   x,
  low,
  high 
)    (((x) > (high)) ? (high) : (((x) < (low)) ? (low) : (x)))
Parameters
xvalue
lowlow bound
highhigh bound
Returns
a value between low and high

◆ HASH_TABLE_MAX_SIZE

#define HASH_TABLE_MAX_SIZE   13845163

The maximal hash table size

◆ HASH_TABLE_MIN_SIZE

#define HASH_TABLE_MIN_SIZE   11

The minimal hash table size

◆ HASH_TABLE_RESIZE

#define HASH_TABLE_RESIZE (   hash_table)
Value:
if ((hash_table->size >= 3 * hash_table->nnodes && \
hash_table->size > HASH_TABLE_MIN_SIZE) || \
(3 * hash_table->size <= hash_table->nnodes && \
hash_table->size < HASH_TABLE_MAX_SIZE)) \
internal_di_hash_table_resize (hash_table);
#define HASH_TABLE_MIN_SIZE
Definition: hash.c:81
#define HASH_TABLE_MAX_SIZE
Definition: hash.c:86

Defines if a resize is necessary

Parameters
hash_tablea di_hash_table

Function Documentation

◆ di_hash_table_destroy()

void di_hash_table_destroy ( di_hash_table hash_table)

Destroys the di_hash_table. If keys and/or values are dynamically allocated, you should either free them first or create the di_hash_table using di_hash_table_new_full. In the latter case the destroy functions you supplied will be called on all keys and values before destroying the di_hash_table.

Parameters
hash_tablea di_hash_table.
135 {
136  size_t i;
137 
138  for (i = 0; i < hash_table->size; i++)
139  internal_di_hash_nodes_destroy (hash_table->nodes[i], hash_table->key_destroy_func, hash_table->value_destroy_func);
140 
141  di_mem_chunk_destroy (hash_table->mem_chunk);
142 
143  di_free (hash_table->nodes);
144  di_free (hash_table);
145 }
void di_free(void *mem)
Definition: mem.c:60
di_mem_chunk * mem_chunk
Definition: hash.c:46
di_destroy_notify * key_destroy_func
Definition: hash.c:49
size_t size
Definition: hash.c:43
di_hash_node ** nodes
Definition: hash.c:45
di_destroy_notify * value_destroy_func
Definition: hash.c:50

References size.

Referenced by di_packages_free(), and di_release_free().

◆ di_hash_table_foreach()

void di_hash_table_foreach ( di_hash_table hash_table,
di_hfunc *  func,
void *  user_data 
)

Calls the given function for each of the key/value pairs in the di_hash_table. The function is passed the key and value of each pair, and the given user_data parameter.

Postcondition
The hash table may not be modified while iterating over it (you can't add/remove items).
Parameters
hash_tablea di_hash_table.
functhe function to call for each key/value pair.
user_datauser data to pass to the function.
247 {
248  di_hash_node *node;
249  size_t i;
250 
251  for (i = 0; i < hash_table->size; i++)
252  for (node = hash_table->nodes[i]; node; node = node->next)
253  func (node->key, node->value, user_data);
254 }
Node of a hash table.
Definition: hash.c:58
void * value
Definition: hash.c:60
void * key
Definition: hash.c:59
di_hash_node * next
Definition: hash.c:61

◆ di_hash_table_insert()

void di_hash_table_insert ( di_hash_table hash_table,
void *  key,
void *  value 
)

Inserts a new key and value into a di_hash_table.

If the key already exists in the di_hash_table its current value is replaced with the new value. If you supplied a value_destroy_func when creating the di_hash_table, the old value is freed using that function. If you supplied a key_destroy_func when creating the di_hash_table, the passed key is freed using that function.

Parameters
hash_tablea di_hash_table.
keya key to insert.
valuethe value to associate with the key.
179 {
180  di_hash_node **node;
181 
182  node = internal_di_hash_table_lookup_node (hash_table, key);
183 
184  if (*node)
185  {
186  if (hash_table->key_destroy_func)
187  hash_table->key_destroy_func (key);
188 
189  if (hash_table->value_destroy_func)
190  hash_table->value_destroy_func ((*node)->value);
191 
192  (*node)->value = value;
193  }
194  else
195  {
196  *node = internal_di_hash_node_new (hash_table, key, value);
197  hash_table->nnodes++;
198  HASH_TABLE_RESIZE (hash_table);
199  }
200 }
#define HASH_TABLE_RESIZE(hash_table)
Definition: hash.c:70
size_t nnodes
Definition: hash.c:44

Referenced by di_packages_append_package().

◆ di_hash_table_lookup()

void* di_hash_table_lookup ( di_hash_table hash_table,
const void *  key 
)

Looks up a key in a di_hash_table.

Parameters
hash_tablea di_hash_table,
keythe key to look up.
Returns
the associated value, or NULL if the key is not found.
170 {
171  di_hash_node *node;
172 
173  node = *internal_di_hash_table_lookup_node (hash_table, key);
174 
175  return node ? node->value : NULL;
176 }

Referenced by di_packages_get_package(), and di_parser_rfc822_read().

◆ di_hash_table_new()

di_hash_table* di_hash_table_new ( di_hash_func  hash_func,
di_equal_func  key_equal_func 
)

Creates a new di_hash_table.

Parameters
hash_funca function to create a hash value from a key. Hash values are used to determine where keys are stored within the di_hash_table data structure.
key_equal_funca function to check two keys for equality. This is used when looking up keys in the di_hash_table.
Returns
a new di_hash_table.
109 {
110  return di_hash_table_new_full (hash_func, key_equal_func, NULL, NULL);
111 }
di_hash_table * di_hash_table_new_full(di_hash_func hash_func, di_equal_func key_equal_func, di_destroy_notify key_destroy_func, di_destroy_notify value_destroy_func)
Definition: hash.c:113

References di_hash_table_new_full().

◆ di_hash_table_new_full()

di_hash_table* di_hash_table_new_full ( di_hash_func  hash_func,
di_equal_func  key_equal_func,
di_destroy_notify  key_destroy_func,
di_destroy_notify  value_destroy_func 
)

Creates a new di_hash_table like di_hash_table_new and allows to specify functions to free the memory allocated for the key and value that get called when removing the entry from the di_hash_table

Parameters
hash_funca function to create a hash value from a key. Hash values are used to determine where keys are stored within the di_hash_table data structure.
key_equal_funca function to check two keys for equality. This is used when looking up keys in the di_hash_table.
key_destroy_funca function to free the memory allocated for the key used when removing the entry from the di_hash_table or NULL if you don't want to supply such a function.
value_destroy_funca function to free the memory allocated for the value used when removing the entry from the di_hash_table or NULL if you don't want to supply such a function.
Returns
a new di_hash_table.
114 {
115  di_hash_table *hash_table;
116  size_t i;
117 
118  hash_table = di_new (di_hash_table, 1);
119  hash_table->size = HASH_TABLE_MIN_SIZE;
120  hash_table->nnodes = 0;
121  hash_table->mem_chunk = di_mem_chunk_new (sizeof (di_hash_node), 4096);
122  hash_table->hash_func = hash_func;
123  hash_table->key_equal_func = key_equal_func;
124  hash_table->key_destroy_func = key_destroy_func;
125  hash_table->value_destroy_func = value_destroy_func;
126  hash_table->nodes = di_new (di_hash_node*, hash_table->size);
127 
128  for (i = 0; i < hash_table->size; i++)
129  hash_table->nodes[i] = NULL;
130 
131  return hash_table;
132 }
di_mem_chunk * di_mem_chunk_new(di_ksize_t atom_size, di_ksize_t area_size)
Definition: mem_chunk.c:87
#define di_new(struct_type, n_structs)
Definition: mem.h:73
Hash table.
Definition: hash.c:42
di_equal_func * key_equal_func
Definition: hash.c:48
di_hash_func * hash_func
Definition: hash.c:47

References di_mem_chunk_new(), di_new, hash_func, HASH_TABLE_MIN_SIZE, key_destroy_func, key_equal_func, mem_chunk, nnodes, nodes, size, and value_destroy_func.

Referenced by di_hash_table_new(), di_packages_alloc(), and di_release_alloc().

◆ di_hash_table_size()

di_ksize_t di_hash_table_size ( di_hash_table hash_table)

Returns the number of elements contained in the di_hash_table.

Parameters
hash_tablea di_hash_table.
Returns
the number of key/value pairs.
257 {
258  return hash_table->nnodes;
259 }

References nnodes.