API reference (dmHash)

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Sdk hash api documentation

Hash functions.


Include:	`#include <dmsdk/dlib/hash.h>`

STRUCTS
struct HashState32	Hash state used for 32-bit incremental hashing
struct HashState64	Hash state used for 64-bit incremental hashing

FUNCTIONS
uint32_t dmHashBuffer32(const void* buffer, uint32_t buffer_len)	Calculate 32-bit hash value from buffer
uint64_t dmHashBuffer64(const void* buffer, uint32_t buffer_len)	calculate 64-bit hash value from buffer
uint32_t dmHashString32(const char* string)	Calculate 32-bit hash value from string
uint64_t dmHashString64(const char* string)	calculate 64-bit hash value from string
const char* dmHashReverseSafe64(uint64_t hash)	get string value from hash
const char* dmHashReverseSafe64(uint64_t hash, uint32_t* length)	get string value from hash
void dmHashInit32(HashState32* hash_state, bool reverse_hash)	Initialize hash-state for 32-bit incremental hashi...
void dmHashClone32(HashState32* hash_state, HashState32* source_hash_state, bool reverse_hash)	Clone 32-bit incremental hash state
void dmHashUpdateBuffer32(HashState32* hash_state, const void* buffer, uint32_t buffer_len)	Incremental hashing
uint32_t dmHashFinal32(HashState32* hash_state)	Finalize incremental hashing and release associate...
void dmHashRelease32(HashState32* hash_state)	Release incremental hashing resources Used to rele...
void dmHashInit64(HashState64* hash_state, reverse_hash)	Initialize hash-state for 64-bit incremental hashi...
void dmHashClone64(HashState64* hash_state, HashState64* source_hash_state, reverse_hash)	Clone 64-bit incremental hash state
void dmHashUpdateBuffer64(HashState64* hash_state, const void* buffer, uint32_t buffer_len)	Incremental hashing
uint64_t dmHashFinal64(HashState64* hash_state)	Finalize incremental hashing and release associate...
void dmHashRelease64(HashState64* hash_state)	Release incremental hashing resources Used to rele...

Functions

dmHashBuffer32

uint32_t dmHashBuffer32(const void* buffer, uint32_t buffer_len)

Calculate 32-bit hash value from buffer

PARAMETERS

`const void*`	`buffer`	Buffer
`uint32_t`	`buffer_len`	Length of buffer

RETURNS

uint32_t hash value

dmHashBuffer64

uint64_t dmHashBuffer64(const void* buffer, uint32_t buffer_len)

calculate 64-bit hash value from buffer

PARAMETERS

`const void*`	`buffer`	Buffer
`uint32_t`	`buffer_len`	Length of buffer

RETURNS

uint64_t hash value

dmHashString32

uint32_t dmHashString32(const char* string)

Calculate 32-bit hash value from string

PARAMETERS

const char* string Null terminated string

RETURNS

uint32_t hash value

dmHashString64

uint64_t dmHashString64(const char* string)

calculate 64-bit hash value from string

PARAMETERS

const char* string Null terminated string

RETURNS

uint64_t hash value

dmHashReverseSafe64

const char* dmHashReverseSafe64(uint64_t hash)

Returns the original string used to produce a hash. Always returns a null terminated string. Returns "" if the original string wasn't found.

PARAMETERS

uint64_t hash hash value

RETURNS

const char* Original string value

dmHashReverseSafe64

const char* dmHashReverseSafe64(uint64_t hash, uint32_t* length)

Reverse hash lookup. Maps hash to original data. It is guaranteed that the returned buffer is null-terminated. If the buffer contains a valid c-string it can safely be used in printf and friends.

PARAMETERS

`uint64_t`	`hash`	hash to lookup
`uint32_t*`	`length`	original data length. Optional argument and NULL-pointer is accepted.

RETURNS

const char* pointer to buffer. 0 if no reverse exists or if reverse lookup is disabled

dmHashInit32

void dmHashInit32(HashState32* hash_state, bool reverse_hash)

Initialize hash-state for 32-bit incremental hashing

PARAMETERS

`HashState32*`	`hash_state`	Hash state
`bool`	`reverse_hash`	true to enable reverse hashing of buffers up to ::DMHASH_MAX_REVERSE_LENGTH

dmHashClone32

void dmHashClone32(HashState32* hash_state, HashState32* source_hash_state, bool reverse_hash)

Clone 32-bit incremental hash state

PARAMETERS

`HashState32*`	`hash_state`	Hash state
`HashState32*`	`source_hash_state`	Source hash state
`bool`	`reverse_hash`	true to enable reverse hashing of buffers up to ::DMHASH_MAX_REVERSE_LENGTH. Ignored if source state reverse hashing is disabled.

dmHashUpdateBuffer32

void dmHashUpdateBuffer32(HashState32* hash_state, const void* buffer, uint32_t buffer_len)

Incremental hashing

PARAMETERS

`HashState32*`	`hash_state`	Hash state
`const void*`	`buffer`	Buffer
`uint32_t`	`buffer_len`	Length of buffer

dmHashFinal32

uint32_t dmHashFinal32(HashState32* hash_state)

Finalize incremental hashing and release associated resources

PARAMETERS

HashState32* hash_state Hash state

RETURNS

uint32_t the hash value

dmHashRelease32

void dmHashRelease32(HashState32* hash_state)

Release incremental hashing resources Used to release assocciated resources for intermediate incremental hash states.

PARAMETERS

HashState32* hash_state Hash state

dmHashInit64

void dmHashInit64(HashState64* hash_state, reverse_hash)

Initialize hash-state for 64-bit incremental hashing

PARAMETERS

`HashState64*`	`hash_state`	Hash state
	`reverse_hash`	true to enable reverse hashing of buffers up to ::DMHASH_MAX_REVERSE_LENGTH

dmHashClone64

void dmHashClone64(HashState64* hash_state, HashState64* source_hash_state, reverse_hash)

Clone 64-bit incremental hash state

PARAMETERS

`HashState64*`	`hash_state`	Hash state
`HashState64*`	`source_hash_state`	Source hash state
	`reverse_hash`	true bool to enable reverse hashing of buffers up to ::DMHASH_MAX_REVERSE_LENGTH. Ignored if source state reverse hashing is disabled.