diff options
Diffstat (limited to 'examples/redis-unstable/src/entry.h')
| -rw-r--r-- | examples/redis-unstable/src/entry.h | 141 |
1 files changed, 0 insertions, 141 deletions
diff --git a/examples/redis-unstable/src/entry.h b/examples/redis-unstable/src/entry.h deleted file mode 100644 index 47aeae3..0000000 --- a/examples/redis-unstable/src/entry.h +++ /dev/null @@ -1,141 +0,0 @@ -/* - * Copyright (c) 2009-Present, Redis Ltd. - * All rights reserved. - * - * Copyright (c) 2024-present, Valkey contributors. - * All rights reserved. - */ - -/* ----------------------------------------------------------------------------- - * Entry - * ----------------------------------------------------------------------------- - * An Entry represents a packed field-value pair with optional expiration metadata. - * Currently it is used only by Hash. - * - * There are 3 different formats for the "entry". In all cases, the "entry" - * pointer points into the allocation and is identical to the "field" sds pointer. - * - * Type 1: Field sds type is an SDS_TYPE_5 - * With this type, both the key and value are embedded in the entry. Expiration - * is not allowed as the SDS_TYPE_5 (on field) doesn't contain any aux bits - * to encode the existence of an expiration. Extra padding is included in - * the value to the size of the physical block. - * - * entry - * | - * +---------V------------+----------------------------+ - * | Field | Value | - * | sdshdr5 | "foo" \0 | sdshdr8 "bar" \0 (padding) | - * +---------+------------+----------------------------+ - * - * Identified by: field sds type is SDS_TYPE_5 - * - * - * Type 2: Field sds type is an SDS_TYPE_8 type - * With this type, both the key and value are embedded. Extra bits in the - * sdshdr8 (on field) are used to encode aux flags which may indicate the - * presence of an optional expiration. Extra padding is included in the value - * to the size of the physical block. - * - * entry - * | - * +--------------+---------V------------+----------------------------+ - * | Expire (opt) | Field | Value | - * | ExpireMeta | sdshdr8 | "foo" \0 | sdshdr8 "bar" \0 (padding) | - * +--------------+---------+------------+----------------------------+ - * - * Identified by: sds type is SDS_TYPE_8 AND has embedded value - * - * - * Type 3: Value is an sds, referenced by pointer - * With this type, the key is embedded, and the value is an sds, referenced - * by pointer. Extra bits in the sdshdr8/16/32 (on field) are used to encode - * aux flags which indicate the presence of a value by pointer. An aux bit - * may indicate the presence of an optional expiration. Note that the - * "field" is not padded, so there's no direct way to identify the length of the allocation. - * - * entry - * | - * +--------------+---------------+----------V----------+--------+ - * | Expire (opt) | Value | Field | / / / /| - * | ExpireMeta | sds (pointer) | sdshdr8+ | "foo" \0 |/ / / / | - * +--------------+-------+-------+----------+----------+--------+ - * | - * +-> sds value - * - * Identified by: Aux bit FIELD_SDS_AUX_BIT_ENTRY_HAS_VALUE_PTR - */ -#ifndef _ENTRY_H_ -#define _ENTRY_H_ - -#include "sds.h" -#include "ebuckets.h" -typedef struct _entry Entry; - -/* The maximum allocation size we want to use for entries with embedded values. */ -#define EMBED_VALUE_MAX_ALLOC_SIZE 128 - -/* Flags for entryCreate() and entryUpdate() */ -#define ENTRY_TAKE_VALUE (1<<1) /* Take ownership of value if possible (not embedded) */ -#define ENTRY_HAS_EXPIRY (1<<2) /* Entry has expiration */ - -/* Returns the value string (sds) from the entry. */ -sds entryGetValue(const Entry *entry); - -/* A pointer to the value pointer. If embedded or doesn't have a value, returns NULL. */ -sds *entryGetValuePtrRef(const Entry *entry); - -/* Gets the expiration timestamp (UNIX time in milliseconds). */ -uint64_t entryGetExpiry(const Entry *entry); - -int entryIsExpired(const Entry *entry); - -/* Returns true if the entry has an expiration timestamp set. */ -int entryHasExpiry(const Entry *entry); - -/* Frees the memory used by the entry (including field/value). */ -void entryFree(Entry *entry, size_t *usable); - -/* Creates a new entry with the given field, value, and optional expiry. - * Flags can be ENTRY_TAKE_VALUE (take ownership of value if not embedded) and - * ENTRY_HAS_EXPIRY (entry has expiration metadata). - * If usable is not NULL, it will be set to the actual allocated size. */ -Entry *entryCreate(sds field, sds value, uint32_t flags, size_t *usable); - -/* Updates the value and/or expiry of an existing entry. - * In case value is NULL, will use the existing entry value. - * Flags can be ENTRY_TAKE_VALUE (take ownership of value if not embedded) and - * ENTRY_HAS_EXPIRY (reserve space for existing expiry). - * If usableDiff not NULL, it will be set to diff in mem usage (newUsable - oldUsable) */ -Entry *entryUpdate(Entry *entry, sds value, uint32_t flags, ssize_t *usableDiff); - -/* Calculate entry allocation size based on SDS alloc fields. - * This is used for size accounting. */ -size_t entryMemUsage(Entry *entry); - -/* Returns the address of the entry allocation. */ -void *entryGetAllocPtr(const Entry *entry); - -/* Defragments the entry and returns the new pointer (if moved). */ -Entry *entryDefrag(Entry *entry, void *(*defragfn)(void *), sds (*sdsdefragfn)(sds)); - -/* Advises allocator to dismiss memory used by entry. */ -void entryDismissMemory(Entry *entry); - -/* Get a reference to the expiry metadata if present, NULL otherwise. */ -static inline ExpireMeta *entryRefExpiryMeta(Entry *entry) { - return entryHasExpiry(entry) ? (ExpireMeta *)entryGetAllocPtr(entry) : NULL; -} - -/* The entry pointer is the field sds, but that's an implementation detail. */ -static inline sds entryGetField(const Entry *entry) { - /* Note: The Entry pointer is identical to the field sds pointer. - * This is a fundamental design assumption verified by the implementation. */ - return (sds)entry; -} - -static inline size_t entryFieldLen(const Entry *entry) { - return sdslen(entryGetField(entry)); -} - -#endif |