/* * Copyright (c) 2009-Present, Redis Ltd. * All rights reserved. * * Licensed under your choice of (a) the Redis Source Available License 2.0 * (RSALv2); or (b) the Server Side Public License v1 (SSPLv1); or (c) the * GNU Affero General Public License v3 (AGPLv3). */ #include "server.h" #include "xxhash.h" #include /* isnan(), isinf() */ /* XXH3 64-bit hash produces 16 hex characters when formatted */ #define DIGEST_HEX_LENGTH 16 /* Forward declarations */ int getGenericCommand(client *c); /*----------------------------------------------------------------------------- * String Commands *----------------------------------------------------------------------------*/ static int checkStringLength(client *c, long long size, long long append) { if (mustObeyClient(c)) return C_OK; /* 'uint64_t' cast is there just to prevent undefined behavior on overflow */ long long total = (uint64_t)size + append; /* Test configured max-bulk-len representing a limit of the biggest string object, * and also test for overflow. */ if (total > server.proto_max_bulk_len || total < size || total < append) { addReplyError(c,"string exceeds maximum allowed size (proto-max-bulk-len)"); return C_ERR; } return C_OK; } /* The setGenericCommand() function implements the SET operation with different * options and variants. This function is called in order to implement the * following commands: SET, SETEX, PSETEX, SETNX, GETSET. * * 'flags' changes the behavior of the command (NX, XX, GET, IFEQ, IFNE, IFDEQ * or IFDNE - see below). * * 'expire' represents an expire to set in form of a Redis object as passed * by the user. It is interpreted according to the specified 'unit'. * * 'match_value' is a value to check against if any of IFEQ/IFNE/IFDEQ/IFDNE is * present. * * 'ok_reply' and 'abort_reply' is what the function will reply to the client * if the operation is performed, or when it is not because of NX or * XX flags. * * If ok_reply is NULL "+OK" is used. * If abort_reply is NULL, "$-1" is used. */ #define OBJ_NO_FLAGS 0 #define OBJ_SET_NX (1<<0) /* Set if key not exists. */ #define OBJ_SET_XX (1<<1) /* Set if key exists. */ #define OBJ_EX (1<<2) /* Set if time in seconds is given */ #define OBJ_PX (1<<3) /* Set if time in ms in given */ #define OBJ_KEEPTTL (1<<4) /* Set and keep the ttl */ #define OBJ_SET_GET (1<<5) /* Set if want to get key before set */ #define OBJ_EXAT (1<<6) /* Set if timestamp in second is given */ #define OBJ_PXAT (1<<7) /* Set if timestamp in ms is given */ #define OBJ_PERSIST (1<<8) /* Set if we need to remove the ttl */ #define OBJ_SET_IFEQ (1<<9) /* Set if value equals match value */ #define OBJ_SET_IFNE (1<<10) /* Set if value does not equal match value */ #define OBJ_SET_IFDEQ (1<<11) /* Set if current digest equals match digest */ #define OBJ_SET_IFDNE (1<<12) /* Set if current digest does not equal match digest */ /* Forward declaration */ static int getExpireMillisecondsOrReply(client *c, robj *expire, int flags, int unit, long long *milliseconds); /* Generic SET command family (SET, SETEX, PSETEX, SETNX) * * Arguments: * valref: A pointer to the robj to be set. This argument may be updated by the function. * The object is expected to have a refcount of 1, allowing its ownership to be * transferred directly to the database to avoid making a copy. If needed, the * function will replace *valref with a new allocation and increment its refcount * so that both the database and the caller maintain valid references. */ void setGenericCommand(client *c, int flags, robj *key, robj **valref, robj *expire, int unit, robj *match_value, robj *ok_reply, robj *abort_reply) { long long milliseconds = 0; /* initialized to avoid any harmless warning */ int found = 0; int setkey_flags = 0; if (expire && getExpireMillisecondsOrReply(c, expire, flags, unit, &milliseconds) != C_OK) { return; } if (flags & OBJ_SET_GET) { if (getGenericCommand(c) == C_ERR) return; } dictEntryLink link = NULL; found = (lookupKeyWriteWithLink(c->db,key,&link) != NULL); if ((flags & OBJ_SET_NX && found) || (flags & (OBJ_SET_XX | OBJ_SET_IFEQ | OBJ_SET_IFDEQ) && !found)) { if (!(flags & OBJ_SET_GET)) { addReply(c, abort_reply ? abort_reply : shared.null[c->resp]); } return; } /* Handle conditional set operations - only set if key is found and condition * is met - otherwise return nil. */ if (found && (flags & (OBJ_SET_IFEQ | OBJ_SET_IFNE | OBJ_SET_IFDEQ | OBJ_SET_IFDNE))) { kvobj *current = lookupKeyRead(c->db, key); if (checkType(c, current, OBJ_STRING)) { return; } if (flags & OBJ_SET_IFEQ || flags & OBJ_SET_IFNE) { robj *current_decoded = getDecodedObject(current); int condition = (flags & OBJ_SET_IFEQ) ? sdscmp(current_decoded->ptr, match_value->ptr) == 0 : sdscmp(current_decoded->ptr, match_value->ptr) != 0; decrRefCount(current_decoded); if (!condition) { if (!(flags & OBJ_SET_GET)) { addReply(c, abort_reply ? abort_reply : shared.null[c->resp]); } return; } } else if (flags & OBJ_SET_IFDEQ || flags & OBJ_SET_IFDNE) { if (validateHexDigest(c, match_value->ptr) != C_OK) return; sds current_digest = stringDigest(current); int condition = flags & OBJ_SET_IFDEQ ? strcasecmp(current_digest, match_value->ptr) == 0 : strcasecmp(current_digest, match_value->ptr) != 0; sdsfree(current_digest); if (!condition) { if (!(flags & OBJ_SET_GET)) { addReply(c, abort_reply ? abort_reply : shared.null[c->resp]); } return; } } } /* When expire is not NULL, we avoid deleting the TTL so it can be updated later instead of being deleted and then created again. */ setkey_flags |= ((flags & OBJ_KEEPTTL) || expire) ? SETKEY_KEEPTTL : 0; setkey_flags |= found ? SETKEY_ALREADY_EXIST : SETKEY_DOESNT_EXIST; setKeyByLink(c, c->db, key, valref, setkey_flags, &link); /* If there's an expiration, setExpireByLink may reallocate the object. * We must update valref to reflect the new object if that happens. */ if (expire) *valref = setExpireByLink(c, c->db, key->ptr, milliseconds, link); /* The client still holds a reference to the original object via c->argv[i], * and will call decrRefCount() at the end of call(). We increment the refcount * from 1 to 2 to ensure both DB and client have valid references. */ incrRefCount(*valref); /* 1->2 */ server.dirty++; notifyKeyspaceEvent(NOTIFY_STRING,"set",key,c->db->id); if (expire) { /* Propagate as SET Key Value PXAT millisecond-timestamp if there is * EX/PX/EXAT flag. */ if (!(flags & OBJ_PXAT)) { robj *milliseconds_obj = createStringObjectFromLongLong(milliseconds); /* If command is exactly "SET key value EX/PX/EXAT ttl", we can just * replace the expire type and value in-place. Otherwise, we need to * rewrite the entire command to strip extra flags (NX, XX, GET, etc). */ if ((c->cmd->proc == setCommand) && c->argc == 5) { rewriteClientCommandArgument(c, 3, shared.pxat); rewriteClientCommandArgument(c, 4, milliseconds_obj); } else { rewriteClientCommandVector(c, 5, shared.set, key, *valref, shared.pxat, milliseconds_obj); } decrRefCount(milliseconds_obj); } notifyKeyspaceEvent(NOTIFY_GENERIC,"expire",key,c->db->id); } if (!(flags & OBJ_SET_GET)) { addReply(c, ok_reply ? ok_reply : shared.ok); } /* Propagate without the GET argument (Isn't needed if we had expire since in that case we completely re-written the command argv) */ if ((flags & OBJ_SET_GET) && !expire) { int argc = 0; int j; robj **argv = zmalloc((c->argc-1)*sizeof(robj*)); for (j=0; j < c->argc; j++) { char *a = c->argv[j]->ptr; /* Skip GET which may be repeated multiple times. */ if (j >= 3 && (a[0] == 'g' || a[0] == 'G') && (a[1] == 'e' || a[1] == 'E') && (a[2] == 't' || a[2] == 'T') && a[3] == '\0') continue; argv[argc++] = c->argv[j]; incrRefCount(c->argv[j]); } replaceClientCommandVector(c, argc, argv); } } /* * Extract the `expire` argument of a given GET/SET command as an absolute timestamp in milliseconds. * * "client" is the client that sent the `expire` argument. * "expire" is the `expire` argument to be extracted. * "flags" represents the behavior of the command (e.g. PX or EX). * "unit" is the original unit of the given `expire` argument (e.g. UNIT_SECONDS). * "milliseconds" is output argument. * * If return C_OK, "milliseconds" output argument will be set to the resulting absolute timestamp. * If return C_ERR, an error reply has been added to the given client. */ static int getExpireMillisecondsOrReply(client *c, robj *expire, int flags, int unit, long long *milliseconds) { int ret = getLongLongFromObjectOrReply(c, expire, milliseconds, NULL); if (ret != C_OK) { return ret; } if (*milliseconds <= 0 || (unit == UNIT_SECONDS && *milliseconds > LLONG_MAX / 1000)) { /* Negative value provided or multiplication is gonna overflow. */ addReplyErrorExpireTime(c); return C_ERR; } if (unit == UNIT_SECONDS) *milliseconds *= 1000; if ((flags & OBJ_PX) || (flags & OBJ_EX)) { *milliseconds += commandTimeSnapshot(); } if (*milliseconds <= 0) { /* Overflow detected. */ addReplyErrorExpireTime(c); return C_ERR; } return C_OK; } #define COMMAND_GET 0 #define COMMAND_SET 1 #define COMMAND_MSETEX 2 /* Extended string command arguments structure */ typedef struct { int flags; int unit; int expire_pos; /* Position of EX/PX flag for replication rewriting */ robj *expire; robj *match_value; /* For IFEQ/IFNE/IFDEQ/IFDNE conditions */ } extendedStringArgs; /* * The parseExtendedStringArgumentsOrReply() function performs the common validation for extended * string arguments used in SET, GET and MSETEX commands. * * Get specific commands - PERSIST/DEL * Set specific commands - XX/NX/GET/IFEQ/IFNE/IFDEQ/IFDNE * Common commands - EX/EXAT/PX/PXAT/KEEPTTL * * Function takes pointers to client, start_pos for where to begin parsing, extendedStringArgs * structure to populate, and command_type which can be COMMAND_GET, COMMAND_SET, or COMMAND_MSETEX. * * If there are any syntax violations C_ERR is returned else C_OK is returned. * * The args structure is updated upon parsing the arguments. Unit and expire are updated if there are any * EX/EXAT/PX/PXAT arguments. Unit is updated to millisecond if PX/PXAT is set. * match_value is updated if any of IFEQ/IFNE/IFDEQ/IFDNE is set. */ int parseExtendedStringArgumentsOrReply(client *c, int start_pos, extendedStringArgs *args, int command_type) { /* Initialize arguments to defaults */ memset(args, 0, sizeof(*args)); args->expire_pos = -1; args->unit = UNIT_SECONDS; int j = start_pos; /* We can have either none or exactly one of these conditionals as they are * mutually exclusive. We'll make sure to check if none of the other flags * are already set if we are going to set one of them. This is done via the * check: * * if (opt == OBJ_SET_XXX && !(*flags & (cond_mut_excl & ~OBJ_SET_XXX))) * * A bit ugly - but concise. */ int cond_mut_excl = OBJ_SET_NX | OBJ_SET_XX | OBJ_SET_IFEQ | OBJ_SET_IFNE | OBJ_SET_IFDEQ | OBJ_SET_IFDNE; for (; j < c->argc; j++) { char *opt = c->argv[j]->ptr; robj *next = (j == c->argc-1) ? NULL : c->argv[j+1]; if ((opt[0] == 'n' || opt[0] == 'N') && (opt[1] == 'x' || opt[1] == 'X') && opt[2] == '\0' && !(args->flags & OBJ_SET_XX) && (command_type == COMMAND_SET || command_type == COMMAND_MSETEX)) { args->flags |= OBJ_SET_NX; } else if ((opt[0] == 'x' || opt[0] == 'X') && (opt[1] == 'x' || opt[1] == 'X') && opt[2] == '\0' && !(args->flags & OBJ_SET_NX) && (command_type == COMMAND_SET || command_type == COMMAND_MSETEX)) { args->flags |= OBJ_SET_XX; } else if ((opt[0] == 'g' || opt[0] == 'G') && (opt[1] == 'e' || opt[1] == 'E') && (opt[2] == 't' || opt[2] == 'T') && opt[3] == '\0' && (command_type == COMMAND_SET)) { args->flags |= OBJ_SET_GET; } else if (!strcasecmp(opt, "KEEPTTL") && !(args->flags & OBJ_PERSIST) && !(args->flags & OBJ_EX) && !(args->flags & OBJ_EXAT) && !(args->flags & OBJ_PX) && !(args->flags & OBJ_PXAT) && (command_type == COMMAND_SET || command_type == COMMAND_MSETEX)) { args->flags |= OBJ_KEEPTTL; } else if (!strcasecmp(opt,"PERSIST") && (command_type == COMMAND_GET) && !(args->flags & OBJ_EX) && !(args->flags & OBJ_EXAT) && !(args->flags & OBJ_PX) && !(args->flags & OBJ_PXAT) && !(args->flags & OBJ_KEEPTTL)) { args->flags |= OBJ_PERSIST; } else if ((opt[0] == 'e' || opt[0] == 'E') && (opt[1] == 'x' || opt[1] == 'X') && opt[2] == '\0' && !(args->flags & OBJ_KEEPTTL) && !(args->flags & OBJ_PERSIST) && !(args->flags & OBJ_EXAT) && !(args->flags & OBJ_PX) && !(args->flags & OBJ_PXAT) && next) { args->flags |= OBJ_EX; args->expire = next; args->expire_pos = j; j++; } else if ((opt[0] == 'p' || opt[0] == 'P') && (opt[1] == 'x' || opt[1] == 'X') && opt[2] == '\0' && !(args->flags & OBJ_KEEPTTL) && !(args->flags & OBJ_PERSIST) && !(args->flags & OBJ_EX) && !(args->flags & OBJ_EXAT) && !(args->flags & OBJ_PXAT) && next) { args->flags |= OBJ_PX; args->unit = UNIT_MILLISECONDS; args->expire = next; args->expire_pos = j; j++; } else if ((opt[0] == 'e' || opt[0] == 'E') && (opt[1] == 'x' || opt[1] == 'X') && (opt[2] == 'a' || opt[2] == 'A') && (opt[3] == 't' || opt[3] == 'T') && opt[4] == '\0' && !(args->flags & OBJ_KEEPTTL) && !(args->flags & OBJ_PERSIST) && !(args->flags & OBJ_EX) && !(args->flags & OBJ_PX) && !(args->flags & OBJ_PXAT) && next) { args->flags |= OBJ_EXAT; args->expire = next; j++; } else if ((opt[0] == 'p' || opt[0] == 'P') && (opt[1] == 'x' || opt[1] == 'X') && (opt[2] == 'a' || opt[2] == 'A') && (opt[3] == 't' || opt[3] == 'T') && opt[4] == '\0' && !(args->flags & OBJ_KEEPTTL) && !(args->flags & OBJ_PERSIST) && !(args->flags & OBJ_EX) && !(args->flags & OBJ_EXAT) && !(args->flags & OBJ_PX) && next) { args->flags |= OBJ_PXAT; args->unit = UNIT_MILLISECONDS; args->expire = next; j++; } else if (!strcasecmp(opt, "ifeq") && next && !(args->flags & (cond_mut_excl & ~OBJ_SET_IFEQ)) && (command_type == COMMAND_SET)) { args->flags |= OBJ_SET_IFEQ; args->match_value = next; j++; } else if (!strcasecmp(opt, "ifne") && next && !(args->flags & (cond_mut_excl & ~OBJ_SET_IFNE)) && (command_type == COMMAND_SET)) { args->flags |= OBJ_SET_IFNE; args->match_value = next; j++; } else if (!strcasecmp(opt, "ifdeq") && next && !(args->flags & (cond_mut_excl & ~OBJ_SET_IFDEQ)) && (command_type == COMMAND_SET)) { args->flags |= OBJ_SET_IFDEQ; args->match_value = next; j++; } else if (!strcasecmp(opt, "ifdne") && next && !(args->flags & (cond_mut_excl & ~OBJ_SET_IFDNE)) && (command_type == COMMAND_SET)) { args->flags |= OBJ_SET_IFDNE; args->match_value = next; j++; } else { addReplyErrorObject(c,shared.syntaxerr); return C_ERR; } } return C_OK; } /* SET key value [NX] [XX] [KEEPTTL] [GET] [EX ] [PX ] * [EXAT ][PXAT ] * [IFEQ |IFNE |IFDEQ | * IFDNE ]*/ void setCommand(client *c) { extendedStringArgs args; if (parseExtendedStringArgumentsOrReply(c, 3, &args, COMMAND_SET) != C_OK) { return; } c->argv[2] = tryObjectEncoding(c->argv[2]); setGenericCommand(c, args.flags, c->argv[1], &(c->argv[2]), args.expire, args.unit, args.match_value, NULL, NULL); } void setnxCommand(client *c) { c->argv[2] = tryObjectEncoding(c->argv[2]); setGenericCommand(c, OBJ_SET_NX, c->argv[1], &(c->argv[2]), NULL, 0, NULL, shared.cone, shared.czero); } void setexCommand(client *c) { c->argv[3] = tryObjectEncoding(c->argv[3]); setGenericCommand(c, OBJ_EX, c->argv[1], &(c->argv[3]), c->argv[2], UNIT_SECONDS, NULL, NULL, NULL); } void psetexCommand(client *c) { c->argv[3] = tryObjectEncoding(c->argv[3]); setGenericCommand(c, OBJ_PX, c->argv[1], &(c->argv[3]), c->argv[2], UNIT_MILLISECONDS, NULL, NULL, NULL); } int getGenericCommand(client *c) { kvobj *o; if ((o = lookupKeyReadOrReply(c, c->argv[1], shared.null[c->resp])) == NULL) return C_OK; if (checkType(c,o,OBJ_STRING)) { return C_ERR; } addReplyBulk(c,o); return C_OK; } void getCommand(client *c) { getGenericCommand(c); } /* * GETEX [PERSIST][EX seconds][PX milliseconds][EXAT seconds-timestamp][PXAT milliseconds-timestamp] * * The getexCommand() function implements extended options and variants of the GET command. Unlike GET * command this command is not read-only. * * The default behavior when no options are specified is same as GET and does not alter any TTL. * * Only one of the below options can be used at a given time. * * 1. PERSIST removes any TTL associated with the key. * 2. EX Set expiry TTL in seconds. * 3. PX Set expiry TTL in milliseconds. * 4. EXAT Same like EX instead of specifying the number of seconds representing the TTL * (time to live), it takes an absolute Unix timestamp * 5. PXAT Same like PX instead of specifying the number of milliseconds representing the TTL * (time to live), it takes an absolute Unix timestamp * * Command would either return the bulk string, error or nil. */ void getexCommand(client *c) { extendedStringArgs args; if (parseExtendedStringArgumentsOrReply(c, 2, &args, COMMAND_GET) != C_OK) { return; } kvobj *o; if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.null[c->resp])) == NULL) return; if (checkType(c,o,OBJ_STRING)) { return; } /* Validate the expiration time value first */ long long milliseconds = 0; if (args.expire && getExpireMillisecondsOrReply(c, args.expire, args.flags, args.unit, &milliseconds) != C_OK) { return; } /* We need to do this before we expire the key or delete it */ addReplyBulk(c,o); /* This command is never propagated as is. It is either propagated as PEXPIRE[AT],DEL,UNLINK or PERSIST. * This why it doesn't need special handling in feedAppendOnlyFile to convert relative expire time to absolute one. */ if (((args.flags & OBJ_PXAT) || (args.flags & OBJ_EXAT)) && checkAlreadyExpired(milliseconds)) { /* When PXAT/EXAT absolute timestamp is specified, there can be a chance that timestamp * has already elapsed so delete the key in that case. */ int deleted = dbGenericDelete(c->db, c->argv[1], server.lazyfree_lazy_expire, DB_FLAG_KEY_EXPIRED); serverAssert(deleted); robj *aux = server.lazyfree_lazy_expire ? shared.unlink : shared.del; rewriteClientCommandVector(c,2,aux,c->argv[1]); keyModified(c, c->db, c->argv[1], NULL, 1); notifyKeyspaceEvent(NOTIFY_GENERIC, "del", c->argv[1], c->db->id); server.dirty++; } else if (args.expire) { o = setExpire(c,c->db,c->argv[1],milliseconds); /* Propagate as PXEXPIREAT millisecond-timestamp if there is * EX/PX/EXAT/PXAT flag and the key has not expired. */ robj *milliseconds_obj = createStringObjectFromLongLong(milliseconds); rewriteClientCommandVector(c,3,shared.pexpireat,c->argv[1],milliseconds_obj); decrRefCount(milliseconds_obj); keyModified(c, c->db, c->argv[1], o, 1); notifyKeyspaceEvent(NOTIFY_GENERIC,"expire",c->argv[1],c->db->id); server.dirty++; } else if (args.flags & OBJ_PERSIST) { if (removeExpire(c->db, c->argv[1])) { keyModified(c, c->db, c->argv[1], o, 1); rewriteClientCommandVector(c, 2, shared.persist, c->argv[1]); notifyKeyspaceEvent(NOTIFY_GENERIC,"persist",c->argv[1],c->db->id); server.dirty++; } } } void getdelCommand(client *c) { if (getGenericCommand(c) == C_ERR) return; if (dbSyncDelete(c->db, c->argv[1])) { /* Propagate as DEL command */ rewriteClientCommandVector(c,2,shared.del,c->argv[1]); keyModified(c, c->db, c->argv[1], NULL, 1); notifyKeyspaceEvent(NOTIFY_GENERIC, "del", c->argv[1], c->db->id); server.dirty++; } } void getsetCommand(client *c) { if (getGenericCommand(c) == C_ERR) return; c->argv[2] = tryObjectEncoding(c->argv[2]); setKey(c, c->db, c->argv[1], &c->argv[2], 0); incrRefCount(c->argv[2]); notifyKeyspaceEvent(NOTIFY_STRING,"set",c->argv[1],c->db->id); server.dirty++; /* Propagate as SET command */ rewriteClientCommandArgument(c,0,shared.set); } void setrangeCommand(client *c) { int64_t oldLen = -1, newLen; long offset; sds value = c->argv[3]->ptr; const size_t value_len = sdslen(value); if (getLongFromObjectOrReply(c,c->argv[2],&offset,NULL) != C_OK) return; if (offset < 0) { addReplyError(c,"offset is out of range"); return; } dictEntryLink link; kvobj *kv = lookupKeyWriteWithLink(c->db, c->argv[1], &link); if (kv == NULL) { /* Return 0 when setting nothing on a non-existing string */ if (value_len == 0) { addReply(c,shared.czero); return; } /* Return when the resulting string exceeds allowed size */ if (checkStringLength(c,offset,value_len) != C_OK) return; newLen = offset+value_len; robj *o = createObject(OBJ_STRING,sdsnewlen(NULL, newLen)); kv = dbAddByLink(c->db, c->argv[1], &o, &link); } else { /* Key exists, check type */ if (checkType(c,kv,OBJ_STRING)) return; /* Return existing string length when setting nothing */ oldLen = stringObjectLen(kv); if (value_len == 0) { addReplyLongLong(c, oldLen); return; } /* Return when the resulting string exceeds allowed size */ if (checkStringLength(c,offset,value_len) != C_OK) return; /* Create a copy when the object is shared or encoded. */ kv = dbUnshareStringValueByLink(c->db, c->argv[1], kv, link); newLen = max(oldLen, (int64_t) (offset + value_len)); updateKeysizesHist(c->db, getKeySlot(c->argv[1]->ptr), OBJ_STRING, oldLen, newLen); } if (value_len > 0) { size_t oldsize = 0; if (server.memory_tracking_per_slot) oldsize = stringObjectAllocSize(kv); kv->ptr = sdsgrowzero(kv->ptr,offset+value_len); if (server.memory_tracking_per_slot) updateSlotAllocSize(c->db, getKeySlot(c->argv[1]->ptr), oldsize, stringObjectAllocSize(kv)); memcpy((char*)kv->ptr+offset,value,value_len); keyModified(c,c->db,c->argv[1],kv,1); notifyKeyspaceEvent(NOTIFY_STRING, "setrange",c->argv[1],c->db->id); server.dirty++; } addReplyLongLong(c,newLen); } void getrangeCommand(client *c) { kvobj *o; long long start, end; char *str, llbuf[32]; size_t strlen; if (getLongLongFromObjectOrReply(c,c->argv[2],&start,NULL) != C_OK) return; if (getLongLongFromObjectOrReply(c,c->argv[3],&end,NULL) != C_OK) return; if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptybulk)) == NULL || checkType(c,o,OBJ_STRING)) return; if (o->encoding == OBJ_ENCODING_INT) { str = llbuf; strlen = ll2string(llbuf,sizeof(llbuf),(long)o->ptr); } else { str = o->ptr; strlen = sdslen(str); } /* Convert negative indexes */ if (start < 0 && end < 0 && start > end) { addReply(c,shared.emptybulk); return; } if (start < 0) start = strlen+start; if (end < 0) end = strlen+end; if (start < 0) start = 0; if (end < 0) end = 0; if ((unsigned long long)end >= strlen) end = strlen-1; /* Precondition: end >= 0 && end < strlen, so the only condition where * nothing can be returned is: start > end. */ if (start > end || strlen == 0) { addReply(c,shared.emptybulk); } else { addReplyBulkCBuffer(c,(char*)str+start,end-start+1); } } void mgetCommand(client *c) { int j; addReplyArrayLen(c,c->argc-1); for (j = 1; j < c->argc; j++) { kvobj *o = lookupKeyRead(c->db, c->argv[j]); if (o == NULL) { addReplyNull(c); } else { if (o->type != OBJ_STRING) { addReplyNull(c); } else { addReplyBulk(c,o); } } } } void msetGenericCommand(client *c, int nx) { int j; if ((c->argc % 2) == 0) { addReplyErrorArity(c); return; } /* Handle the NX flag. The MSETNX semantic is to return zero and don't * set anything if at least one key already exists. */ if (nx) { for (j = 1; j < c->argc; j += 2) { if (lookupKeyWrite(c->db,c->argv[j]) != NULL) { addReply(c, shared.czero); return; } } } for (j = 1; j < c->argc; j += 2) { c->argv[j+1] = tryObjectEncoding(c->argv[j+1]); /* if 'NX', no need set flags SETKEY_DOESNT_EXIST. Already verified earlier! */ setKey(c, c->db, c->argv[j], &(c->argv[j+1]) , 0 /*flags*/); incrRefCount(c->argv[j+1]); /* refcnt not incr by setKey() */ notifyKeyspaceEvent(NOTIFY_STRING,"set",c->argv[j],c->db->id); } server.dirty += (c->argc-1)/2; addReply(c, nx ? shared.cone : shared.ok); } void msetCommand(client *c) { msetGenericCommand(c,0); } void msetnxCommand(client *c) { msetGenericCommand(c,1); } void msetexCommand(client *c) { /* Parse numkeys parameter */ long kv_count; if (getRangeLongFromObjectOrReply(c, c->argv[1], 1, INT_MAX, &kv_count, "invalid numkeys value") != C_OK) { return; } /* Validate we have enough arguments: command + numkeys + (key-value pairs) * 2 * Be careful to avoid overflow when calculating kv_count * 2 */ if ((long long)kv_count * 2 + 2 > c->argc) { addReplyError(c, "wrong number of key-value pairs"); return; } extendedStringArgs args; if (parseExtendedStringArgumentsOrReply(c, kv_count * 2 + 2, &args, COMMAND_MSETEX) != C_OK) { return; } /* Validate the expiration time value first */ long long milliseconds = 0; if (args.expire && getExpireMillisecondsOrReply(c, args.expire, args.flags, args.unit, &milliseconds) != C_OK) { return; } if (args.flags & (OBJ_SET_NX | OBJ_SET_XX)) { /* Check NX/XX conditions for each key - pattern from setGenericCommand */ for (int j = 0; j < kv_count; j++) { int key_idx = (j * 2) + 2; robj *found = lookupKeyWrite(c->db, c->argv[key_idx]); if ((args.flags & OBJ_SET_NX && found) || (args.flags & OBJ_SET_XX && !found)) { addReply(c, shared.czero); return; } } } /* Set all key-value pairs */ for (int j = 0; j < kv_count; j++) { int key_idx = (j * 2) + 2; int val_idx = key_idx + 1; c->argv[val_idx] = tryObjectEncoding(c->argv[val_idx]); /* Handle KEEPTTL - preserve existing TTL */ int setkey_flags = 0; if (args.flags & OBJ_KEEPTTL) { setkey_flags |= SETKEY_KEEPTTL; } setKey(c, c->db, c->argv[key_idx], &(c->argv[val_idx]), setkey_flags); incrRefCount(c->argv[val_idx]); /* Set expiration for each key (but not for KEEPTTL) */ if (args.expire && !(args.flags & OBJ_KEEPTTL)) { setExpire(c, c->db, c->argv[key_idx], milliseconds); notifyKeyspaceEvent(NOTIFY_GENERIC,"expire",c->argv[key_idx],c->db->id); } notifyKeyspaceEvent(NOTIFY_STRING,"set",c->argv[key_idx],c->db->id); } /* Handle replication rewriting for relative expiration times */ if (args.expire && !(args.flags & OBJ_PXAT) && !(args.flags & OBJ_EXAT) && args.expire_pos != -1) { /* Convert EX/PX (relative) to PXAT (absolute) for consistent replication */ robj *milliseconds_obj = createStringObjectFromLongLong(milliseconds); rewriteClientCommandArgument(c, args.expire_pos, shared.pxat); rewriteClientCommandArgument(c, args.expire_pos + 1, milliseconds_obj); decrRefCount(milliseconds_obj); } server.dirty += kv_count; addReply(c, shared.cone); } void incrDecrCommand(client *c, long long incr) { long long value, oldvalue; robj *new; dictEntryLink link; kvobj *o = lookupKeyWriteWithLink(c->db, c->argv[1], &link); if (checkType(c,o,OBJ_STRING)) return; if (getLongLongFromObjectOrReply(c,o,&value,NULL) != C_OK) return; oldvalue = value; if ((incr < 0 && oldvalue < 0 && incr < (LLONG_MIN-oldvalue)) || (incr > 0 && oldvalue > 0 && incr > (LLONG_MAX-oldvalue))) { addReplyError(c,"increment or decrement would overflow"); return; } value += incr; if (o && o->refcount == 1 && o->encoding == OBJ_ENCODING_INT && value >= LONG_MIN && value <= LONG_MAX) { new = o; o->ptr = (void*)((long)value); updateKeysizesHist(c->db, getKeySlot(c->argv[1]->ptr), OBJ_STRING, (int64_t) sdigits10(oldvalue), (int64_t) sdigits10(value)); } else { new = createStringObjectFromLongLongForValue(value); if (o) { /* replace value in db and also update keysizes hist */ dbReplaceValueWithLink(c->db, c->argv[1], &new, link); } else { /* Add new key to db and also update keysizes hist */ dbAddByLink(c->db, c->argv[1], &new, &link); } } addReplyLongLongFromStr(c,new); keyModified(c,c->db,c->argv[1],new,1); notifyKeyspaceEvent(NOTIFY_STRING,"incrby",c->argv[1],c->db->id); server.dirty++; } void incrCommand(client *c) { incrDecrCommand(c,1); } void decrCommand(client *c) { incrDecrCommand(c,-1); } void incrbyCommand(client *c) { long long incr; if (getLongLongFromObjectOrReply(c, c->argv[2], &incr, NULL) != C_OK) return; incrDecrCommand(c,incr); } void decrbyCommand(client *c) { long long incr; if (getLongLongFromObjectOrReply(c, c->argv[2], &incr, NULL) != C_OK) return; /* Overflow check: negating LLONG_MIN will cause an overflow */ if (incr == LLONG_MIN) { addReplyError(c, "decrement would overflow"); return; } incrDecrCommand(c,-incr); } void incrbyfloatCommand(client *c) { long double incr, value; dictEntryLink link; kvobj *o = lookupKeyWriteWithLink(c->db,c->argv[1],&link); if (checkType(c,o,OBJ_STRING)) return; if (getLongDoubleFromObjectOrReply(c,o,&value,NULL) != C_OK || getLongDoubleFromObjectOrReply(c,c->argv[2],&incr,NULL) != C_OK) return; value += incr; if (isnan(value) || isinf(value)) { addReplyError(c,"increment would produce NaN or Infinity"); return; } robj *new = createStringObjectFromLongDouble(value,1); if (o) dbReplaceValueWithLink(c->db, c->argv[1], &new, link); else dbAddByLink(c->db, c->argv[1], &new, &link); keyModified(c,c->db,c->argv[1],new,1); notifyKeyspaceEvent(NOTIFY_STRING,"incrbyfloat",c->argv[1],c->db->id); server.dirty++; addReplyBulk(c,new); /* Always replicate INCRBYFLOAT as a SET command with the final value * in order to make sure that differences in float precision or formatting * will not create differences in replicas or after an AOF restart. */ rewriteClientCommandArgument(c,0,shared.set); rewriteClientCommandArgument(c,2,new); rewriteClientCommandArgument(c,3,shared.keepttl); } void appendCommand(client *c) { size_t totlen; robj *append; kvobj *o; size_t oldsize = 0; dictEntryLink link; o = lookupKeyWriteWithLink(c->db,c->argv[1],&link); if (o == NULL) { /* Create the key */ c->argv[2] = tryObjectEncoding(c->argv[2]); o = dbAddByLink(c->db, c->argv[1], &c->argv[2], &link); incrRefCount(c->argv[2]); totlen = stringObjectLen(c->argv[2]); } else { /* Key exists, check type */ if (checkType(c,o,OBJ_STRING)) return; /* "append" is an argument, so always an sds */ append = c->argv[2]; size_t append_len = sdslen(append->ptr); if (checkStringLength(c,stringObjectLen(o),append_len) != C_OK) return; /* Append the value */ o = dbUnshareStringValueByLink(c->db,c->argv[1],o,link); if (server.memory_tracking_per_slot) oldsize = stringObjectAllocSize(o); o->ptr = sdscatlen(o->ptr,append->ptr,append_len); if (server.memory_tracking_per_slot) updateSlotAllocSize(c->db, getKeySlot(c->argv[1]->ptr), oldsize, stringObjectAllocSize(o)); totlen = sdslen(o->ptr); int64_t oldlen = totlen - append_len; updateKeysizesHist(c->db, getKeySlot(c->argv[1]->ptr), OBJ_STRING, oldlen, totlen); } keyModified(c,c->db,c->argv[1],o,1); notifyKeyspaceEvent(NOTIFY_STRING,"append",c->argv[1],c->db->id); server.dirty++; addReplyLongLong(c,totlen); } void strlenCommand(client *c) { kvobj *kv; if ((kv = lookupKeyReadOrReply(c, c->argv[1], shared.czero)) == NULL || checkType(c, kv, OBJ_STRING)) return; addReplyLongLong(c,stringObjectLen(kv)); } /* LCS key1 key2 [LEN] [IDX] [MINMATCHLEN ] [WITHMATCHLEN] */ void lcsCommand(client *c) { uint32_t i, j; long long minmatchlen = 0; sds a = NULL, b = NULL; int getlen = 0, getidx = 0, withmatchlen = 0; kvobj *obja = lookupKeyRead(c->db, c->argv[1]); kvobj *objb = lookupKeyRead(c->db, c->argv[2]); if ((obja && obja->type != OBJ_STRING) || (objb && objb->type != OBJ_STRING)) { addReplyError(c, "The specified keys must contain string values"); /* Don't cleanup the objects, we need to do that * only after calling getDecodedObject(). */ obja = NULL; objb = NULL; goto cleanup; } obja = obja ? getDecodedObject(obja) : createStringObject("",0); objb = objb ? getDecodedObject(objb) : createStringObject("",0); a = obja->ptr; b = objb->ptr; for (j = 3; j < (uint32_t)c->argc; j++) { char *opt = c->argv[j]->ptr; int moreargs = (c->argc-1) - j; if (!strcasecmp(opt,"IDX")) { getidx = 1; } else if (!strcasecmp(opt,"LEN")) { getlen = 1; } else if (!strcasecmp(opt,"WITHMATCHLEN")) { withmatchlen = 1; } else if (!strcasecmp(opt,"MINMATCHLEN") && moreargs) { if (getLongLongFromObjectOrReply(c,c->argv[j+1],&minmatchlen,NULL) != C_OK) goto cleanup; if (minmatchlen < 0) minmatchlen = 0; j++; } else { addReplyErrorObject(c,shared.syntaxerr); goto cleanup; } } /* Complain if the user passed ambiguous parameters. */ if (getlen && getidx) { addReplyError(c, "If you want both the length and indexes, please just use IDX."); goto cleanup; } /* Detect string truncation or later overflows. */ if (sdslen(a) >= UINT32_MAX-1 || sdslen(b) >= UINT32_MAX-1) { addReplyError(c, "String too long for LCS"); goto cleanup; } /* Compute the LCS using the vanilla dynamic programming technique of * building a table of LCS(x,y) substrings. */ uint32_t alen = sdslen(a); uint32_t blen = sdslen(b); /* Setup an uint32_t array to store at LCS[i,j] the length of the * LCS A0..i-1, B0..j-1. Note that we have a linear array here, so * we index it as LCS[j+(blen+1)*i] */ #define LCS(A,B) lcs[(B)+((A)*(blen+1))] /* Try to allocate the LCS table, and abort on overflow or insufficient memory. */ unsigned long long lcssize = (unsigned long long)(alen+1)*(blen+1); /* Can't overflow due to the size limits above. */ unsigned long long lcsalloc = lcssize * sizeof(uint32_t); uint32_t *lcs = NULL; if (lcsalloc < SIZE_MAX && lcsalloc / lcssize == sizeof(uint32_t)) { if (lcsalloc > (size_t)server.proto_max_bulk_len) { addReplyError(c, "Insufficient memory, transient memory for LCS exceeds proto-max-bulk-len"); goto cleanup; } lcs = ztrymalloc(lcsalloc); } if (!lcs) { addReplyError(c, "Insufficient memory, failed allocating transient memory for LCS"); goto cleanup; } /* Start building the LCS table. */ for (uint32_t i = 0; i <= alen; i++) { for (uint32_t j = 0; j <= blen; j++) { if (i == 0 || j == 0) { /* If one substring has length of zero, the * LCS length is zero. */ LCS(i,j) = 0; } else if (a[i-1] == b[j-1]) { /* The len LCS (and the LCS itself) of two * sequences with the same final character, is the * LCS of the two sequences without the last char * plus that last char. */ LCS(i,j) = LCS(i-1,j-1)+1; } else { /* If the last character is different, take the longest * between the LCS of the first string and the second * minus the last char, and the reverse. */ uint32_t lcs1 = LCS(i-1,j); uint32_t lcs2 = LCS(i,j-1); LCS(i,j) = lcs1 > lcs2 ? lcs1 : lcs2; } } } /* Store the actual LCS string in "result" if needed. We create * it backward, but the length is already known, we store it into idx. */ uint32_t idx = LCS(alen,blen); sds result = NULL; /* Resulting LCS string. */ void *arraylenptr = NULL; /* Deferred length of the array for IDX. */ uint32_t arange_start = alen, /* alen signals that values are not set. */ arange_end = 0, brange_start = 0, brange_end = 0; /* Do we need to compute the actual LCS string? Allocate it in that case. */ int computelcs = getidx || !getlen; if (computelcs) result = sdsnewlen(SDS_NOINIT,idx); /* Start with a deferred array if we have to emit the ranges. */ uint32_t arraylen = 0; /* Number of ranges emitted in the array. */ if (getidx) { addReplyMapLen(c,2); addReplyBulkCString(c,"matches"); arraylenptr = addReplyDeferredLen(c); } i = alen, j = blen; while (computelcs && i > 0 && j > 0) { int emit_range = 0; if (a[i-1] == b[j-1]) { /* If there is a match, store the character and reduce * the indexes to look for a new match. */ result[idx-1] = a[i-1]; /* Track the current range. */ if (arange_start == alen) { arange_start = i-1; arange_end = i-1; brange_start = j-1; brange_end = j-1; } else { /* Let's see if we can extend the range backward since * it is contiguous. */ if (arange_start == i && brange_start == j) { arange_start--; brange_start--; } else { emit_range = 1; } } /* Emit the range if we matched with the first byte of * one of the two strings. We'll exit the loop ASAP. */ if (arange_start == 0 || brange_start == 0) emit_range = 1; idx--; i--; j--; } else { /* Otherwise reduce i and j depending on the largest * LCS between, to understand what direction we need to go. */ uint32_t lcs1 = LCS(i-1,j); uint32_t lcs2 = LCS(i,j-1); if (lcs1 > lcs2) i--; else j--; if (arange_start != alen) emit_range = 1; } /* Emit the current range if needed. */ uint32_t match_len = arange_end - arange_start + 1; if (emit_range) { if (minmatchlen == 0 || match_len >= minmatchlen) { if (arraylenptr) { addReplyArrayLen(c,2+withmatchlen); addReplyArrayLen(c,2); addReplyLongLong(c,arange_start); addReplyLongLong(c,arange_end); addReplyArrayLen(c,2); addReplyLongLong(c,brange_start); addReplyLongLong(c,brange_end); if (withmatchlen) addReplyLongLong(c,match_len); arraylen++; } } arange_start = alen; /* Restart at the next match. */ } } /* Signal modified key, increment dirty, ... */ /* Reply depending on the given options. */ if (arraylenptr) { addReplyBulkCString(c,"len"); addReplyLongLong(c,LCS(alen,blen)); setDeferredArrayLen(c,arraylenptr,arraylen); } else if (getlen) { addReplyLongLong(c,LCS(alen,blen)); } else { addReplyBulkSds(c,result); result = NULL; } /* Cleanup. */ sdsfree(result); zfree(lcs); cleanup: if (obja) decrRefCount(obja); if (objb) decrRefCount(objb); return; } /* Validate that a digest string has the correct length (DIGEST_HEX_LENGTH characters). * Note: This only validates length, not whether characters are valid hex digits. * Invalid hex characters will simply fail to match during comparison. * Returns C_OK if length is correct, C_ERR otherwise. */ int validateHexDigest(client *c, const sds digest) { size_t len = sdslen(digest); if (len != DIGEST_HEX_LENGTH) { addReplyErrorFormat(c, "must be exactly %d hexadecimal characters", DIGEST_HEX_LENGTH); return C_ERR; } return C_OK; } /* Return the xxh3 hash of a string object as a hex string stored in an sds. * The user is responsible for freeing the sds. */ sds stringDigest(robj *o) { serverAssert(o && o->type == OBJ_STRING); XXH64_hash_t hash = 0; if (sdsEncodedObject(o)) { hash = XXH3_64bits(o->ptr, sdslen(o->ptr)); } else if (o->encoding == OBJ_ENCODING_INT) { char buf[LONG_STR_SIZE]; size_t len = ll2string(buf,sizeof(buf),(long)o->ptr); hash = XXH3_64bits(buf, len); } else { serverPanic("Wrong obj->encoding stringDigest()"); } sds hexhash = sdsempty(); hexhash = sdscatprintf(hexhash, "%0" STRINGIFY(DIGEST_HEX_LENGTH) PRIx64, hash); return hexhash; } /* DIGEST key * * Return digest of the key's value computed via XXH3 hash. The key must be a * STRING object. */ void digestCommand(client *c) { kvobj *o; if ((o = lookupKeyReadOrReply(c, c->argv[1], shared.null[c->resp])) == NULL) return; if (checkType(c,o,OBJ_STRING)) return; addReplyBulkSds(c, stringDigest(o)); }