diff options
| -rw-r--r-- | src/module.c | 60 | ||||
| -rw-r--r-- | src/redismodule.h | 2 | ||||
| -rw-r--r-- | tests/modules/keyspace_events.c | 17 | ||||
| -rw-r--r-- | tests/unit/moduleapi/keyspace_events.tcl | 12 |
4 files changed, 83 insertions, 8 deletions
diff --git a/src/module.c b/src/module.c index e0309ae6b..8e9526dad 100644 --- a/src/module.c +++ b/src/module.c @@ -1138,6 +1138,65 @@ void RM_RetainString(RedisModuleCtx *ctx, RedisModuleString *str) { } } +/** +* This function can be used instead of RedisModule_RetainString(). +* The main difference between the two is that this function will always +* succeed, whereas RedisModule_RetainString() may fail because of an +* assertion. +* +* The function returns a pointer to RedisModuleString, which is owned +* by the caller. It requires a call to RedisModule_FreeString() to free +* the string when automatic memory management is disabled for the context. +* When automatic memory management is enabled, you can either call +* RedisModule_FreeString() or let the automation free it. +* +* This function is more efficient than RedisModule_CreateStringFromString() +* because whenever possible, it avoids copying the underlying +* RedisModuleString. The disadvantage of using this function is that it +* might not be possible to use RedisModule_StringAppendBuffer() on the +* returned RedisModuleString. +* +* It is possible to call this function with a NULL context. + */ +RedisModuleString* RM_HoldString(RedisModuleCtx *ctx, RedisModuleString *str) { + if (str->refcount == OBJ_STATIC_REFCOUNT) { + return RM_CreateStringFromString(ctx, str); + } + + incrRefCount(str); + if (ctx != NULL) { + /* + * Put the str in the auto memory management of the ctx. + * It might already be there, in this case, the ref count will + * be 2 and we will decrease the ref count twice and free the + * object in the auto memory free function. + * + * Why we can not do the same trick of just remove the object + * from the auto memory (like in RM_RetainString)? + * This code shows the issue: + * + * RM_AutoMemory(ctx); + * str1 = RM_CreateString(ctx, "test", 4); + * str2 = RM_HoldString(ctx, str1); + * RM_FreeString(str1); + * RM_FreeString(str2); + * + * If after the RM_HoldString we would just remove the string from + * the auto memory, this example will cause access to a freed memory + * on 'RM_FreeString(str2);' because the String will be free + * on 'RM_FreeString(str1);'. + * + * So it's safer to just increase the ref count + * and add the String to auto memory again. + * + * The limitation is that it is not possible to use RedisModule_StringAppendBuffer + * on the String. + */ + autoMemoryAdd(ctx,REDISMODULE_AM_STRING,str); + } + return str; +} + /* Given a string module object, this function returns the string pointer * and length of the string. The returned pointer and length should only * be used for read only accesses and never modified. */ @@ -7832,6 +7891,7 @@ void moduleRegisterCoreAPI(void) { REGISTER_API(LatencyAddSample); REGISTER_API(StringAppendBuffer); REGISTER_API(RetainString); + REGISTER_API(HoldString); REGISTER_API(StringCompare); REGISTER_API(GetContextFromIO); REGISTER_API(GetKeyNameFromIO); diff --git a/src/redismodule.h b/src/redismodule.h index 2599d3129..2f2213677 100644 --- a/src/redismodule.h +++ b/src/redismodule.h @@ -569,6 +569,7 @@ void REDISMODULE_API_FUNC(RedisModule__Assert)(const char *estr, const char *fil void REDISMODULE_API_FUNC(RedisModule_LatencyAddSample)(const char *event, mstime_t latency); int REDISMODULE_API_FUNC(RedisModule_StringAppendBuffer)(RedisModuleCtx *ctx, RedisModuleString *str, const char *buf, size_t len); void REDISMODULE_API_FUNC(RedisModule_RetainString)(RedisModuleCtx *ctx, RedisModuleString *str); +RedisModuleString* REDISMODULE_API_FUNC(RedisModule_HoldString)(RedisModuleCtx *ctx, RedisModuleString *str); int REDISMODULE_API_FUNC(RedisModule_StringCompare)(RedisModuleString *a, RedisModuleString *b); RedisModuleCtx *REDISMODULE_API_FUNC(RedisModule_GetContextFromIO)(RedisModuleIO *io); const RedisModuleString *REDISMODULE_API_FUNC(RedisModule_GetKeyNameFromIO)(RedisModuleIO *io); @@ -807,6 +808,7 @@ static int RedisModule_Init(RedisModuleCtx *ctx, const char *name, int ver, int REDISMODULE_GET_API(LatencyAddSample); REDISMODULE_GET_API(StringAppendBuffer); REDISMODULE_GET_API(RetainString); + REDISMODULE_GET_API(HoldString); REDISMODULE_GET_API(StringCompare); REDISMODULE_GET_API(GetContextFromIO); REDISMODULE_GET_API(GetKeyNameFromIO); diff --git a/tests/modules/keyspace_events.c b/tests/modules/keyspace_events.c index b2296c1cb..db3977be1 100644 --- a/tests/modules/keyspace_events.c +++ b/tests/modules/keyspace_events.c @@ -48,7 +48,7 @@ static int KeySpace_Notification(RedisModuleCtx *ctx, int type, const char *even int nokey; RedisModule_DictGetC(loaded_event_log, (void*)keyName, strlen(keyName), &nokey); if(nokey){ - RedisModule_DictSetC(loaded_event_log, (void*)keyName, strlen(keyName), NULL); + RedisModule_DictSetC(loaded_event_log, (void*)keyName, strlen(keyName), RedisModule_HoldString(ctx, key)); } } @@ -63,9 +63,15 @@ static int cmdIsKeyLoaded(RedisModuleCtx *ctx, RedisModuleString **argv, int arg const char* key = RedisModule_StringPtrLen(argv[1], NULL); int nokey; - RedisModule_DictGetC(loaded_event_log, (void*)key, strlen(key), &nokey); + RedisModuleString* keyStr = RedisModule_DictGetC(loaded_event_log, (void*)key, strlen(key), &nokey); + RedisModule_ReplyWithArray(ctx, 2); RedisModule_ReplyWithLongLong(ctx, !nokey); + if(nokey){ + RedisModule_ReplyWithNull(ctx); + }else{ + RedisModule_ReplyWithString(ctx, keyStr); + } return REDISMODULE_OK; } @@ -93,6 +99,13 @@ int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) } int RedisModule_OnUnload(RedisModuleCtx *ctx) { + RedisModuleDictIter *iter = RedisModule_DictIteratorStartC(loaded_event_log, "^", NULL, 0); + char* key; + size_t keyLen; + RedisModuleString* val; + while((key = RedisModule_DictNextC(iter, &keyLen, (void**)&val))){ + RedisModule_FreeString(ctx, val); + } RedisModule_FreeDict(ctx, loaded_event_log); loaded_event_log = NULL; return REDISMODULE_OK; diff --git a/tests/unit/moduleapi/keyspace_events.tcl b/tests/unit/moduleapi/keyspace_events.tcl index cb959ab52..5b3db0c0a 100644 --- a/tests/unit/moduleapi/keyspace_events.tcl +++ b/tests/unit/moduleapi/keyspace_events.tcl @@ -11,12 +11,12 @@ tags "modules" { r zadd t 1 f1 2 f2 r xadd s * f v r debug reload - assert_equal 1 [r keyspace.is_key_loaded x] - assert_equal 1 [r keyspace.is_key_loaded y] - assert_equal 1 [r keyspace.is_key_loaded z] - assert_equal 1 [r keyspace.is_key_loaded p] - assert_equal 1 [r keyspace.is_key_loaded t] - assert_equal 1 [r keyspace.is_key_loaded s] + assert_equal {1 x} [r keyspace.is_key_loaded x] + assert_equal {1 y} [r keyspace.is_key_loaded y] + assert_equal {1 z} [r keyspace.is_key_loaded z] + assert_equal {1 p} [r keyspace.is_key_loaded p] + assert_equal {1 t} [r keyspace.is_key_loaded t] + assert_equal {1 s} [r keyspace.is_key_loaded s] } } }
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