Macros
#define	REDIS_SIMPLE_STRING_SIZE 256
	(bytes) Only store up to this many characters from Redis confirms and errors.

#define	REDIS_TIMEOUT_SECONDS 3
	(seconds) Abort with an error if cannot send before this timeout (<=0 for not timeout)

Functions
int	redisxAbortBlockAsync (RedisClient *cl)

RESP *	redisxExecBlockAsync (RedisClient *cl)

RedisClient *	redisxGetClient (Redis *redis, enum redisx_channel channel)

RedisClient *	redisxGetLockedConnectedClient (Redis *redis, enum redisx_channel channel)

int	redisxIgnoreReplyAsync (RedisClient *cl)

int	redisxLockClient (RedisClient *cl)

int	redisxLockConnected (RedisClient *cl)

RESP *	redisxReadReplyAsync (RedisClient *cl)

int	redisxResetClient (RedisClient *cl)

int	redisxSendArrayRequestAsync (RedisClient cl, char args[], int lengths[], int n)

int	redisxSendRequestAsync (RedisClient cl, const char command, const char arg1, const char arg2, const char *arg3)

int	redisxSkipReplyAsync (RedisClient *cl)

int	redisxStartBlockAsync (RedisClient *cl)

int	redisxUnlockClient (RedisClient *cl)

Detailed Description

Date: Created on Aug 26, 2024

Author: Attila Kovacs

Basic I/O (send/receive) functions for the RedisX library.

Function Documentation

◆ redisxAbortBlockAsync()

int redisxAbortBlockAsync ( RedisClient * cl )

Abort an atomic transaction block. It sends DISCARD.

Parameters

cl	Pointer to a Redis client

Returns: X_SUCCESS (0) if successful, or X_NULL if the client is NULL, or else X_NO_SERVICE if not connected ot the client or if send() failed.

See also: redisxStartBlockAsync()

References redisxIgnoreReplyAsync(), TRUE, x_error(), X_NULL, and X_SUCCESS.

◆ redisxExecBlockAsync()

RESP * redisxExecBlockAsync ( RedisClient * cl )

Finish and execute an atomic transaction block. It sends EXEC, skips through all OK and QUEUED acknowledgements, and returns the reply to the transaction block itself.

Parameters

cl	Pointer to a Redis client

Returns: The array RESP returned by EXEC, or NULL if there was an error.

See also: redisxStartBlockAsync(); redisxAbortBlockAsync()

References redisxDestroyRESP(), redisxReadReplyAsync(), redisxSkipReplyAsync(), RESP_ARRAY, RESP_ERROR, TRUE, RESP::type, x_error(), and x_trace_null().

◆ redisxGetClient()

RedisClient * redisxGetClient	(	Redis *	redis,
		enum redisx_channel	channel
	)

Returns the redis client for a given connection type in a Redis instance.

Parameters

redis	Pointer to a Redis instance.
channel	REDISX_INTERACTIVE_CHANNEL, REDISX_PIPELINE_CHANNEL, or REDISX_SUBSCRIPTION_CHANNEL

Returns: Pointer to the matching Redis client, or NULL if the channel argument is invalid.

References REDISX_CHANNELS, and x_error().

◆ redisxGetLockedConnectedClient()

RedisClient * redisxGetLockedConnectedClient	(	Redis *	redis,
		enum redisx_channel	channel
	)

Returns the redis client for a given connection type in a Redis instance, with the exclusive access lock if the client is valid and is connected, or else NULL. It is effectively the combination of redisxGetClient() followed by redisxLockConnected().

Parameters

redis	Pointer to a Redis instance.
channel	REDISX_INTERACTIVE_CHANNEL, REDISX_PIPELINE_CHANNEL, or REDISX_SUBSCRIPTION_CHANNEL

Returns: The locked client, if it is enabled, or NULL if the redis argument is NULL, the channel is invalid, or the requested client is not currently connected.

See also: redisxGetClient(); redisxUnlockClient(); redisxLockConnected()

References redisxGetClient(), redisxLockConnected(), X_SUCCESS, and x_trace_null().

◆ redisxIgnoreReplyAsync()

int redisxIgnoreReplyAsync ( RedisClient * cl )

Silently consumes a reply from the specified Redis channel.

Parameters

cl	Pointer to a Redis channel.

Returns: X_SUCCESS if a response was successfully consumed, or REDIS_NULL if a valid response could not be obtained.

References REDIS_NULL, redisxDestroyRESP(), redisxReadReplyAsync(), x_error(), X_NULL, X_SUCCESS, and x_trace().

◆ redisxLockClient()

int redisxLockClient ( RedisClient * cl )

Get exclusive write access to the specified Redis channel.

Parameters

cl	Pointer to the Redis client instance.

Returns: X_SUCCESS if the exclusive lock for the channel was successfully obtained X_FAILURE if pthread_mutex_lock() returned an error X_NULL if the client is NULL.

See also: redisxLockConnected(); redisxUnlockClient()

References x_error(), X_FAILURE, X_NULL, and X_SUCCESS.

◆ redisxLockConnected()

int redisxLockConnected ( RedisClient * cl )

Lock a channel, but only if it has been enabled for communication.

Parameters

cl	Pointer to the Redis client instance

Returns: X_SUCCESS (0) if an excusive lock to the channel has been granted. X_FAILURE if pthread_mutex_lock() returned an error X_NULL if the client is NULL REDIS_INVALID_CHANNEL if the channel is not enabled/connected.

See also: redisxLockClient(); redisxUnlockClient(); redisxGetLockedConnectedClient()

References redisxLockClient(), redisxUnlockClient(), x_error(), X_NO_SERVICE, and X_SUCCESS.

◆ redisxReadReplyAsync()

RESP * redisxReadReplyAsync ( RedisClient * cl )

Reads a response from Redis and returns it.

Parameters

cl	Pointer to a Redis channel

Returns: The RESP structure for the reponse received from Redis, or NULL if an error was encountered (errno will be set to describe the error, which may either be an errno produced by recv() or EBADMSG if the message was corrupted and/or unparseable.

References FALSE, RESP::n, REDIS_INCOMPLETE_TRANSFER, REDIS_SIMPLE_STRING_SIZE, REDIS_UNEXPECTED_RESP, redisxDestroyRESP(), redisxReadReplyAsync(), RESP_ARRAY, RESP_BULK_STRING, RESP_ERROR, RESP_INT, RESP_SIMPLE_STRING, RESP::type, RESP::value, x_error(), X_FAILURE, X_PARSE_ERROR, X_SUCCESS, x_trace_null(), and xStringCopyOf().

◆ redisxResetClient()

int redisxResetClient ( RedisClient * cl )

Sends a RESET request to the specified Redis client. The server will perform a reset as if the client disconnected and reconnected again.

Parameters

cl	The Redis client

Returns: X_SUCCESS (0) if successful, or X_NULL if the client is NULL, or another error code (<0) from redisx.h / xchange.h.

References REDIS_UNEXPECTED_RESP, redisxCheckRESP(), redisxDestroyRESP(), redisxLockConnected(), redisxReadReplyAsync(), redisxSendRequestAsync(), redisxUnlockClient(), RESP_SIMPLE_STRING, RESP::value, x_error(), X_NULL, and X_SUCCESS.

◆ redisxSendArrayRequestAsync()

int redisxSendArrayRequestAsync	(	RedisClient *	cl,
		char *	args[],
		int	lengths[],
		int	n
	)

Send a Redis request with an arbitrary number of arguments.

Parameters

cl	Pointer to the Redis client.
args	The array of string arguments to send.
lengths	Array indicating the number of bytes to send from each string argument. Zero or negative values can be used to determine the string length automatically using strlen(), and the length argument itself may be NULL to determine the lengths of all string arguments automatically.
n	The number of arguments to send.

Returns: X_SUCCESS (0) on success or X_NULL if the client is NULL, or else X_NO_SERVICE if not connected to the client or if send() failed.

References FALSE, REDISX_CMDBUF_SIZE, TRUE, x_error(), X_NULL, and X_SUCCESS.

◆ redisxSendRequestAsync()

int redisxSendRequestAsync	(	RedisClient *	cl,
		const char *	command,
		const char *	arg1,
		const char *	arg2,
		const char *	arg3
	)

Send a command (with up to 3 arguments) to the Redis server. The caller must have an exclusive lock on the client for this version. The arguments supplied will be used up to the first non-NULL value.

Parameters

cl	Pointer to the Redis client instance.
command	Redis command string.
arg1	Optional first string argument or NULL.
arg2	Optional second string argument or NULL.
arg3	Optional third string argument or NULL.

Returns: X_SUCCESS (0) on success or X_NULL if the client is NULL, or else X_NO_SERVICE if not connected to the client or if send() failed

References redisxSendArrayRequestAsync(), x_error(), X_NAME_INVALID, X_NULL, and X_SUCCESS.

◆ redisxSkipReplyAsync()

int redisxSkipReplyAsync ( RedisClient * cl )

Instructs Redis to skip sending a reply for the next command.

Sends CLIENT REPLY SKIP

Parameters

cl	Pointer to the Redis client to use.

Returns: X_SUCCESS (0) on success or X_NULL if the client is NULL, or else X_NO_SERVICE if not connected to the Redis server on the requested channel, or if send() failed.

References TRUE, x_error(), X_NULL, and X_SUCCESS.

◆ redisxStartBlockAsync()

int redisxStartBlockAsync ( RedisClient * cl )

Starts an atomic Redis transaction block, by sending MULTI on the specified client connection. Redis transaction blocks behave just like scripts (in fact they are effectively improptu scripts themselves). As such the rules of Redis scripting apply, such as you cannot call LUA from within a transaction block (which is a real pity...)

Once you start a transaction block you may ignore all acknowledgedments such as OK and QUEUED responses that Redis sends back. These will be 'processed' in bulk by redisEndBlockAsync(), at the end of the transaction block.

Parameters

cl	Pointer to a Redis client.

Returns: X_SUCCESS (0) if successful, or X_NULL if the Redis client is NULL, or X_NO_SERVICE if not connected to the client server or if send() failed.

See also: redisxExecBlockAsync(); redisxAbortBlockAsync()

References TRUE, x_error(), X_NULL, and X_SUCCESS.

◆ redisxUnlockClient()

int redisxUnlockClient ( RedisClient * cl )

Relinquish exclusive write access to the specified Redis channel

Parameters

cl	Pointer to the Redis client instance

Returns: X_SUCCESS if the exclusive lock for the channel was successfully obtained X_FAILURE if pthread_mutex_lock() returned an error X_NULL if the client is NULL

See also: redisxLockClient(); redisxLockConnected()

References x_error(), X_FAILURE, X_NULL, and X_SUCCESS.

Macros

Functions

Detailed Description

Function Documentation

◆ redisxAbortBlockAsync()

◆ redisxExecBlockAsync()

◆ redisxGetClient()

◆ redisxGetLockedConnectedClient()

◆ redisxIgnoreReplyAsync()

◆ redisxLockClient()

◆ redisxLockConnected()

◆ redisxReadReplyAsync()

◆ redisxResetClient()

◆ redisxSendArrayRequestAsync()

◆ redisxSendRequestAsync()

◆ redisxSkipReplyAsync()

◆ redisxStartBlockAsync()

◆ redisxUnlockClient()