An opaque object that manages associations of key-value pairs. More...

Related Functions
(Note that these are not member functions.)
PascalHashTable *	PHNew (OPHeap *heap, uint64_t num_objects, double load, size_t key_inline_size, size_t valsize)
	Constructor for PascalHashTable. More...

void	PHDestroy (PascalHashTable *rhh)
	Destructor for PascalHashTable. More...

bool	PHInsertCustom (PascalHashTable rhh, OPHash hasher, void key, size_t keysize, void *val)
	Associates the specified key and value with custom hash function. More...

bool	PHUpsertCustom (PascalHashTable rhh, OPHash hasher, void key, size_t keysize, void *val_ref, bool is_duplicate)
	Update or insert depends on whether the key already exists in the hash table using custom hash function. More...

void *	PHGetCustom (PascalHashTable rhh, OPHash hasher, void key, size_t keysize)
	Obtain the value associated with the key and hash function. Returns NULL if the key was not found. More...

void *	PHDeleteCustom (PascalHashTable rhh, OPHash hasher, void key, size_t keysize)
	Deletes the key-value entry with specified hash function. More...

static bool	PHInsert (PascalHashTable rhh, void key, size_t keysize, void *val)
	Associates the specified key and value using default hash function. More...

static bool	PHUpsert (PascalHashTable rhh, void key, size_t keysize, void *val_ref, bool is_duplicate)
	Update or insert depends on whether the key already exists in the hash table. More...

static void *	PHGet (PascalHashTable rhh, void key, size_t keysize)
	Obtain the value associated with the key using default hash function. Returns NULL if the key was not found. More...

static void *	PHDelete (PascalHashTable rhh, void key, size_t keysize)
	Deletes the key-value entry using default hash function. More...

uint64_t	PHObjcnt (PascalHashTable *rhh)
	Obtain the number of objects stored in this hash table.

uint64_t	PHCapacity (PascalHashTable *rhh)
	Obtain the number of objects can be stored in this hash table.

size_t	PHKeyInlineSize (PascalHashTable *rhh)
	Obtain the size of the key that can be stored inline in the hash table. If the size of the key is larger than this size, the key would not be inline but allocated somewhere in the OPHeap.

size_t	PHValSize (PascalHashTable *rhh)
	Obtain the size of the value configured for this hash table.

void	PHIterate (PascalHashTable rhh, OPHashIterator iterator, void context)
	Iterates over all key-value pairs in this hash table with user specified context. More...

void	PHPrintStat (PascalHashTable *rhh)
	Prints the accumulated count for each probing number.

Detailed Description

An opaque object that manages associations of key-value pairs.

This object is not thread safe.

Friends And Related Function Documentation

◆ PHNew()

PascalHashTable * PHNew	(	OPHeap *	heap,
		uint64_t	num_objects,
		double	load,
		size_t	key_inline_size,
		size_t	valsize
	)

Parameters

heap	OPHeap instance.
num_objects	number of object we decided to put in.
load	(0.0-1.0) how full the table could be before expansion.
key_inline_size	Size to store the key inline. If the key size is larger than this value, the key would be copied to OPHeap and get referenced by a pointer. If key_inline_size is set to 0, pointer is always used.
valsize	length of the value measured in bytes. This value can be zero for hashset.

Returns: PascalHashTable instance if allocation succeeded, else return NULL.

◆ PHDestroy()

void PHDestroy ( PascalHashTable * rhh )

Parameters

rhh	PascalHashTable instance to destroy.

All the keys managed by this instance will get dealloc as well. User need to manage the value deallocation prior calling this method.

◆ PHInsertCustom()

bool PHInsertCustom	(	PascalHashTable *	rhh,
		OPHash	hasher,
		void *	key,
		size_t	keysize,
		void *	val
	)

Parameters

rhh	PascalHashTable instance.
hasher	hash function.
key	pointer the the key
keysize	length of key data, measured in bytes.
val	pointer to the value.

Returns: true if the operation succeeded, false otherwise.

The content pointed by key and val will be copied into the hash table. If the value size were 0, only the key get copied. When there's a key collision, the coresponding value get replaced.

If the inserted key-value pairs exceeded the original size user configured, the hash table will resized with a larger capacity. If the resize failed, false is returned.

◆ PHUpsertCustom()

bool PHUpsertCustom	(	PascalHashTable *	rhh,
		OPHash	hasher,
		void *	key,
		size_t	keysize,
		void **	val_ref,
		bool *	is_duplicate
	)

Parameters

rhh	RobinHoodHash instance.
hasher	hash function.
key	pointer to the key.
keysize	length of the key data, measured in bytes.
val_ref	reference of value pointer.
is_duplicate	reference of duplication boolean variable.

Returns: true if the operation succeeded, false otherwise.

This method does not insert the value automatically, instead it provides the pointer to the address where value can be inserted or overriden.

If the inserted key-value pairs exceeded the original size user configured, the hash table will resized with a larger capacity. If the resize failed, false is returned.

◆ PHGetCustom()

void * PHGetCustom	(	PascalHashTable *	rhh,
		OPHash	hasher,
		void *	key,
		size_t	keysize
	)

Parameters

rhh	PascalHashTable instance.
hasher	hash function.
key	pointer to the key.
keysize	length of the key data. measured in bytes.

Returns: pointer to the value if found, NULL otherwise.

If the value size were set to 0, PHGetCustom would still return a pointer to where it would store the value. User can still use the returned value to exam if the key were present in the hash table.

◆ PHDeleteCustom()

void * PHDeleteCustom	(	PascalHashTable *	rhh,
		OPHash	hasher,
		void *	key,
		size_t	keysize
	)

Parameters

rhh	PascalHashTable instance.
hasher	hash function.
key	pointer to the key.
keysize	length of the key data, measured in bytes.

Returns: pointer to the value if found, NULL otherwise.

The key would get deallocated after deletion. Table will resize when many entries are deleted.

◆ PHInsert()

static bool PHInsert	(	PascalHashTable *	rhh,
		void *	key,
		size_t	keysize,
		void *	val
	)

Parameters

rhh	PascalHashTable instance.
key	pointer the the key
keysize	length of key data, measured in bytes.
val	pointer to the value.

Returns: true if the operation succeeded, false otherwise.

The content pointed by key and val will be copied into the hash table. If the value size were 0, only the key get copied. When there's a key collision, the coresponding value get replaced.

If the inserted key-value pairs exceeded the original size user configured, the hash table will resized with a larger capacity. If the resize failed, false is returned.

Definition at line 177 of file pascal_hash_table.h.

◆ PHUpsert()

static bool PHUpsert	(	PascalHashTable *	rhh,
		void *	key,
		size_t	keysize,
		void **	val_ref,
		bool *	is_duplicate
	)

Parameters

rhh	RobinHoodHash instance.
key	pointer to the key.
keysize	length of the key data, measured in bytes.
val_ref	reference of value pointer.
is_duplicate	reference of duplication boolean variable.

Returns: true if the operation succeeded, false otherwise.

This method does not insert the value automatically, instead it provides the pointer to the address where value can be inserted or overriden.

If the inserted key-value pairs exceeded the original size user configured, the hash table will resized with a larger capacity. If the resize failed, false is returned.

Definition at line 202 of file pascal_hash_table.h.

◆ PHGet()

static void * PHGet	(	PascalHashTable *	rhh,
		void *	key,
		size_t	keysize
	)

Parameters

rhh	PascalHashTable instance.
key	pointer to the key.
keysize	length of the key data. measured in bytes.

Returns: pointer to the value if found, NULL otherwise.

If the value size were set to 0, PHGetCustom would still return a pointer to where it would store the value. User can still use the returned value to exam if the key were present in the hash table.

Definition at line 224 of file pascal_hash_table.h.

◆ PHDelete()

static void * PHDelete	(	PascalHashTable *	rhh,
		void *	key,
		size_t	keysize
	)

Parameters

rhh	PascalHashTable instance.
key	pointer to the key.
keysize	length of the key data, measured in bytes.

Returns: pointer to the value if found, NULL otherwise.

The key would get deallocated after deletion. Table will resize when many entries are deleted.

Definition at line 242 of file pascal_hash_table.h.

◆ PHIterate()

void PHIterate	(	PascalHashTable *	rhh,
		OPHashIterator	iterator,
		void *	context
	)

Parameters

rhh	PascalHashTable instance.
iterator	function pointer to user defined iterator function.
context	user defined context.

// Function interface matches OPHashIterator
void my_iterator(void* key, void* value,
                 size_t keysize, size_t valsize,
                 void* context)
{
  // Obtain the object we passed in.
  struct MyStruct* my_s = (struct MyStruct*) context;
  // assumes both key and value were null terminated string
  printf("key: %s, value: %s\n", key, value);
}
// User defined context
struct MyStruct my_s;
// PHIterate takes in a PascalHashTable object, a fuction pointer
// OPHashIterator and a user defined context for iteration.
PHIterate(rhh, &my_iterator, &my_s);

The documentation for this struct was generated from the following file:

opic/hash/pascal_hash_table.h

Related Functions

Detailed Description

Friends And Related Function Documentation

◆ PHNew()

◆ PHDestroy()

◆ PHInsertCustom()

◆ PHUpsertCustom()

◆ PHGetCustom()

◆ PHDeleteCustom()

◆ PHInsert()

◆ PHUpsert()

◆ PHGet()

◆ PHDelete()

◆ PHIterate()