hashtable.c File Reference

#include <stdint.h>
#include <string.h>
#include "libavutil/attributes.h"
#include "libavutil/crc.h"
#include "libavutil/error.h"
#include "libavutil/macros.h"
#include "libavutil/mem.h"
#include "hashtable.h"

Go to the source code of this file.

Data Structures
struct	FFHashtableContext

Macros
#define	ALIGN   _Alignof(size_t)
#define	ENTRY_PSL_VAL(entry)   (*(size_t*)(entry))
#define	ENTRY_KEY_PTR(entry)   ((entry) + sizeof(size_t))
#define	ENTRY_VAL_PTR(entry)   (ENTRY_KEY_PTR(entry) + ctx->key_size)
#define	KEYS_EQUAL(k1, k2)   (!memcmp((k1), (k2), ctx->key_size))

Functions
av_cold int	ff_hashtable_alloc (FFHashtableContext **ctx, size_t key_size, size_t val_size, size_t max_entries)
	Create a fixed-sized Robin Hood hash table. More...
static size_t	hash_key (const struct FFHashtableContext *ctx, const void *key)
int	ff_hashtable_get (const struct FFHashtableContext *ctx, const void *key, void *val)
	Look up a value from a hash table given a key. More...
int	ff_hashtable_set (struct FFHashtableContext *ctx, const void *key, const void *val)
	Store a value in a hash table given a key. More...
int	ff_hashtable_delete (struct FFHashtableContext *ctx, const void *key)
	Delete a value from a hash table given a key. More...
void	ff_hashtable_clear (struct FFHashtableContext *ctx)
	Delete all values from a hash table. More...
av_cold void	ff_hashtable_freep (FFHashtableContext **ctx)
	Free a hash table. More...

Macro Definition Documentation

ALIGN

#define ALIGN   _Alignof(size_t)

Definition at line 32 of file hashtable.c.

ENTRY_PSL_VAL

#define ENTRY_PSL_VAL

(

entry

)

(*(size_t*)(entry))

Definition at line 53 of file hashtable.c.

ENTRY_KEY_PTR

#define ENTRY_KEY_PTR

(

entry

)

((entry) + sizeof(size_t))

Definition at line 54 of file hashtable.c.

ENTRY_VAL_PTR

#define ENTRY_VAL_PTR

(

entry

)

(ENTRY_KEY_PTR(entry) + ctx->key_size)

Definition at line 55 of file hashtable.c.

KEYS_EQUAL

#define KEYS_EQUAL	(		k1,
			k2
	)		(!memcmp((k1), (k2), ctx->key_size))

Definition at line 57 of file hashtable.c.

Function Documentation

ff_hashtable_alloc()

av_cold int ff_hashtable_alloc	(	struct FFHashtableContext **	ctx,
		size_t	key_size,
		size_t	val_size,
		size_t	max_entries
	)

Create a fixed-sized Robin Hood hash table.

Parameters

ctx	context to allocate and initialize
key_size	size of key type in bytes
val_size	size of value type in bytes
max_entries	maximum number of key-value pairs to store

Returns

zero on success, nonzero on error

Definition at line 59 of file hashtable.c.

Referenced by dxv_init(), and main().

hash_key()

static size_t hash_key ( const struct FFHashtableContext *  ctx, const void *  key  )

static

Definition at line 92 of file hashtable.c.

Referenced by ff_hashtable_delete(), ff_hashtable_get(), and ff_hashtable_set().

ff_hashtable_get()

int ff_hashtable_get	(	const struct FFHashtableContext *	ctx,
		const void *	key,
		void *	val
	)

Look up a value from a hash table given a key.

Parameters

ctx	hash table context
key	pointer to key data
val	destination pointer for value data

Returns

1 if the key is found, zero if the key is not found

Definition at line 97 of file hashtable.c.

Referenced by dxv_compress_dxt1(), and main().

ff_hashtable_set()

int ff_hashtable_set	(	struct FFHashtableContext *	ctx,
		const void *	key,
		const void *	val
	)

Store a value in a hash table given a key.

Parameters

ctx	hash table context
key	pointer to key data
val	pointer for value data

Returns

1 if the key is written, zero if the key is not written due to the hash table reaching max capacity

Definition at line 119 of file hashtable.c.

Referenced by dxv_compress_dxt1(), and main().

ff_hashtable_delete()

int ff_hashtable_delete	(	struct FFHashtableContext *	ctx,
		const void *	key
	)

Delete a value from a hash table given a key.

Parameters

ctx	hash table context
key	pointer to key data

Returns

1 if the key is deleted, zero if the key is not deleted due to not being found

Definition at line 163 of file hashtable.c.

Referenced by dxv_compress_dxt1(), and main().

ff_hashtable_clear()

void ff_hashtable_clear

(

struct FFHashtableContext *

ctx

)

Delete all values from a hash table.

Parameters

ctx	hash table context

Definition at line 201 of file hashtable.c.

Referenced by dxv_compress_dxt1().

ff_hashtable_freep()

av_cold void ff_hashtable_freep

(

struct FFHashtableContext **

ctx

)

Free a hash table.

Parameters

ctx	hash table context

Definition at line 206 of file hashtable.c.

Referenced by dxv_close(), ff_hashtable_alloc(), and main().