漫话Redis源码之一百零六

2024-02-06 09:32

本文主要是介绍漫话Redis源码之一百零六,希望对大家解决编程问题提供一定的参考价值,需要的开发者们随着小编来一起学习吧!

blocking command相关的操作,简单看一下就行了:

#define UNUSED(x) (void)(x)/* Reply callback for blocking command BLOCK.DEBUG */
int HelloBlock_Reply(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {UNUSED(argv);UNUSED(argc);int *myint = RedisModule_GetBlockedClientPrivateData(ctx);return RedisModule_ReplyWithLongLong(ctx,*myint);
}/* Timeout callback for blocking command BLOCK.DEBUG */
int HelloBlock_Timeout(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {UNUSED(argv);UNUSED(argc);RedisModuleBlockedClient *bc = RedisModule_GetBlockedClientHandle(ctx);RedisModule_BlockedClientMeasureTimeEnd(bc);return RedisModule_ReplyWithSimpleString(ctx,"Request timedout");
}/* Private data freeing callback for BLOCK.DEBUG command. */
void HelloBlock_FreeData(RedisModuleCtx *ctx, void *privdata) {UNUSED(ctx);RedisModule_Free(privdata);
}/* The thread entry point that actually executes the blocking part* of the command BLOCK.DEBUG. */
void *BlockDebug_ThreadMain(void *arg) {void **targ = arg;RedisModuleBlockedClient *bc = targ[0];long long delay = (unsigned long)targ[1];long long enable_time_track = (unsigned long)targ[2];if (enable_time_track)RedisModule_BlockedClientMeasureTimeStart(bc);RedisModule_Free(targ);struct timespec ts;ts.tv_sec = delay / 1000;ts.tv_nsec = (delay % 1000) * 1000000;nanosleep(&ts, NULL);int *r = RedisModule_Alloc(sizeof(int));*r = rand();if (enable_time_track)RedisModule_BlockedClientMeasureTimeEnd(bc);RedisModule_UnblockClient(bc,r);return NULL;
}/* The thread entry point that actually executes the blocking part* of the command BLOCK.DOUBLE_DEBUG. */
void *DoubleBlock_ThreadMain(void *arg) {void **targ = arg;RedisModuleBlockedClient *bc = targ[0];long long delay = (unsigned long)targ[1];RedisModule_BlockedClientMeasureTimeStart(bc);RedisModule_Free(targ);struct timespec ts;ts.tv_sec = delay / 1000;ts.tv_nsec = (delay % 1000) * 1000000;nanosleep(&ts, NULL);int *r = RedisModule_Alloc(sizeof(int));*r = rand();RedisModule_BlockedClientMeasureTimeEnd(bc);/* call again RedisModule_BlockedClientMeasureTimeStart() and* RedisModule_BlockedClientMeasureTimeEnd and ensure that the* total execution time is 2x the delay. */RedisModule_BlockedClientMeasureTimeStart(bc);nanosleep(&ts, NULL);RedisModule_BlockedClientMeasureTimeEnd(bc);RedisModule_UnblockClient(bc,r);return NULL;
}void HelloBlock_Disconnected(RedisModuleCtx *ctx, RedisModuleBlockedClient *bc) {RedisModule_Log(ctx,"warning","Blocked client %p disconnected!",(void*)bc);
}/* BLOCK.DEBUG <delay_ms> <timeout_ms> -- Block for <count> milliseconds, then reply with* a random number. Timeout is the command timeout, so that you can test* what happens when the delay is greater than the timeout. */
int HelloBlock_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {if (argc != 3) return RedisModule_WrongArity(ctx);long long delay;long long timeout;if (RedisModule_StringToLongLong(argv[1],&delay) != REDISMODULE_OK) {return RedisModule_ReplyWithError(ctx,"ERR invalid count");}if (RedisModule_StringToLongLong(argv[2],&timeout) != REDISMODULE_OK) {return RedisModule_ReplyWithError(ctx,"ERR invalid count");}pthread_t tid;RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx,HelloBlock_Reply,HelloBlock_Timeout,HelloBlock_FreeData,timeout);/* Here we set a disconnection handler, however since this module will* block in sleep() in a thread, there is not much we can do in the* callback, so this is just to show you the API. */RedisModule_SetDisconnectCallback(bc,HelloBlock_Disconnected);/* Now that we setup a blocking client, we need to pass the control* to the thread. However we need to pass arguments to the thread:* the delay and a reference to the blocked client handle. */void **targ = RedisModule_Alloc(sizeof(void*)*3);targ[0] = bc;targ[1] = (void*)(unsigned long) delay;// pass 1 as flag to enable time trackingtarg[2] = (void*)(unsigned long) 1;if (pthread_create(&tid,NULL,BlockDebug_ThreadMain,targ) != 0) {RedisModule_AbortBlock(bc);return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");}return REDISMODULE_OK;
}/* BLOCK.DEBUG_NOTRACKING <delay_ms> <timeout_ms> -- Block for <count> milliseconds, then reply with* a random number. Timeout is the command timeout, so that you can test* what happens when the delay is greater than the timeout.* this command does not track background time so the background time should no appear in stats*/
int HelloBlockNoTracking_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {if (argc != 3) return RedisModule_WrongArity(ctx);long long delay;long long timeout;if (RedisModule_StringToLongLong(argv[1],&delay) != REDISMODULE_OK) {return RedisModule_ReplyWithError(ctx,"ERR invalid count");}if (RedisModule_StringToLongLong(argv[2],&timeout) != REDISMODULE_OK) {return RedisModule_ReplyWithError(ctx,"ERR invalid count");}pthread_t tid;RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx,HelloBlock_Reply,HelloBlock_Timeout,HelloBlock_FreeData,timeout);/* Here we set a disconnection handler, however since this module will* block in sleep() in a thread, there is not much we can do in the* callback, so this is just to show you the API. */RedisModule_SetDisconnectCallback(bc,HelloBlock_Disconnected);/* Now that we setup a blocking client, we need to pass the control* to the thread. However we need to pass arguments to the thread:* the delay and a reference to the blocked client handle. */void **targ = RedisModule_Alloc(sizeof(void*)*3);targ[0] = bc;targ[1] = (void*)(unsigned long) delay;// pass 0 as flag to enable time trackingtarg[2] = (void*)(unsigned long) 0;if (pthread_create(&tid,NULL,BlockDebug_ThreadMain,targ) != 0) {RedisModule_AbortBlock(bc);return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");}return REDISMODULE_OK;
}/* BLOCK.DOUBLE_DEBUG <delay_ms> -- Block for 2 x <count> milliseconds,* then reply with a random number.* This command is used to test multiple calls to RedisModule_BlockedClientMeasureTimeStart()* and RedisModule_BlockedClientMeasureTimeEnd() within the same execution. */
int HelloDoubleBlock_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {if (argc != 2) return RedisModule_WrongArity(ctx);long long delay;if (RedisModule_StringToLongLong(argv[1],&delay) != REDISMODULE_OK) {return RedisModule_ReplyWithError(ctx,"ERR invalid count");}pthread_t tid;RedisModuleBlockedClient *bc = RedisModule_BlockClient(ctx,HelloBlock_Reply,HelloBlock_Timeout,HelloBlock_FreeData,0);/* Now that we setup a blocking client, we need to pass the control* to the thread. However we need to pass arguments to the thread:* the delay and a reference to the blocked client handle. */void **targ = RedisModule_Alloc(sizeof(void*)*2);targ[0] = bc;targ[1] = (void*)(unsigned long) delay;if (pthread_create(&tid,NULL,DoubleBlock_ThreadMain,targ) != 0) {RedisModule_AbortBlock(bc);return RedisModule_ReplyWithError(ctx,"-ERR Can't start thread");}return REDISMODULE_OK;
}RedisModuleBlockedClient *blocked_client = NULL;/* BLOCK.BLOCK [TIMEOUT] -- Blocks the current client until released* or TIMEOUT seconds. If TIMEOUT is zero, no timeout function is* registered.*/
int Block_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {if (RedisModule_IsBlockedReplyRequest(ctx)) {RedisModuleString *r = RedisModule_GetBlockedClientPrivateData(ctx);return RedisModule_ReplyWithString(ctx, r);} else if (RedisModule_IsBlockedTimeoutRequest(ctx)) {RedisModule_UnblockClient(blocked_client, NULL); /* Must be called to avoid leaks. */blocked_client = NULL;return RedisModule_ReplyWithSimpleString(ctx, "Timed out");}if (argc != 2) return RedisModule_WrongArity(ctx);long long timeout;if (RedisModule_StringToLongLong(argv[1], &timeout) != REDISMODULE_OK) {return RedisModule_ReplyWithError(ctx, "ERR invalid timeout");}if (blocked_client) {return RedisModule_ReplyWithError(ctx, "ERR another client already blocked");}/* Block client. We use this function as both a reply and optional timeout* callback and differentiate the different code flows above.*/blocked_client = RedisModule_BlockClient(ctx, Block_RedisCommand,timeout > 0 ? Block_RedisCommand : NULL, NULL, timeout);return REDISMODULE_OK;
}/* BLOCK.IS_BLOCKED -- Returns 1 if we have a blocked client, or 0 otherwise.*/
int IsBlocked_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {UNUSED(argv);UNUSED(argc);RedisModule_ReplyWithLongLong(ctx, blocked_client ? 1 : 0);return REDISMODULE_OK;
}/* BLOCK.RELEASE [reply] -- Releases the blocked client and produce the specified reply.*/
int Release_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {if (argc != 2) return RedisModule_WrongArity(ctx);if (!blocked_client) {return RedisModule_ReplyWithError(ctx, "ERR No blocked client");}RedisModuleString *replystr = argv[1];RedisModule_RetainString(ctx, replystr);int err = RedisModule_UnblockClient(blocked_client, replystr);blocked_client = NULL;RedisModule_ReplyWithSimpleString(ctx, "OK");return REDISMODULE_OK;
}int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {UNUSED(argv);UNUSED(argc);if (RedisModule_Init(ctx,"block",1,REDISMODULE_APIVER_1)== REDISMODULE_ERR) return REDISMODULE_ERR;if (RedisModule_CreateCommand(ctx,"block.debug",HelloBlock_RedisCommand,"",0,0,0) == REDISMODULE_ERR)return REDISMODULE_ERR;if (RedisModule_CreateCommand(ctx,"block.double_debug",HelloDoubleBlock_RedisCommand,"",0,0,0) == REDISMODULE_ERR)return REDISMODULE_ERR;if (RedisModule_CreateCommand(ctx,"block.debug_no_track",HelloBlockNoTracking_RedisCommand,"",0,0,0) == REDISMODULE_ERR)return REDISMODULE_ERR;if (RedisModule_CreateCommand(ctx, "block.block",Block_RedisCommand, "", 0, 0, 0) == REDISMODULE_ERR)return REDISMODULE_ERR;if (RedisModule_CreateCommand(ctx,"block.is_blocked",IsBlocked_RedisCommand,"",0,0,0) == REDISMODULE_ERR)return REDISMODULE_ERR;if (RedisModule_CreateCommand(ctx,"block.release",Release_RedisCommand,"",0,0,0) == REDISMODULE_ERR)return REDISMODULE_ERR;return REDISMODULE_OK;
}

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