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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 17:31:02 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 17:31:02 +0000
commitbb12c1fd00eb51118749bbbc69c5596835fcbd3b (patch)
tree88038a98bd31c1b765f3390767a2ec12e37c79ec /src/cluster.h
parentInitial commit. (diff)
downloadredis-bb12c1fd00eb51118749bbbc69c5596835fcbd3b.tar.xz
redis-bb12c1fd00eb51118749bbbc69c5596835fcbd3b.zip
Adding upstream version 5:7.0.15.upstream/5%7.0.15upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/cluster.h')
-rw-r--r--src/cluster.h411
1 files changed, 411 insertions, 0 deletions
diff --git a/src/cluster.h b/src/cluster.h
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+#ifndef __CLUSTER_H
+#define __CLUSTER_H
+
+/*-----------------------------------------------------------------------------
+ * Redis cluster data structures, defines, exported API.
+ *----------------------------------------------------------------------------*/
+
+#define CLUSTER_SLOTS 16384
+#define CLUSTER_OK 0 /* Everything looks ok */
+#define CLUSTER_FAIL 1 /* The cluster can't work */
+#define CLUSTER_NAMELEN 40 /* sha1 hex length */
+#define CLUSTER_PORT_INCR 10000 /* Cluster port = baseport + PORT_INCR */
+
+/* The following defines are amount of time, sometimes expressed as
+ * multiplicators of the node timeout value (when ending with MULT). */
+#define CLUSTER_FAIL_REPORT_VALIDITY_MULT 2 /* Fail report validity. */
+#define CLUSTER_FAIL_UNDO_TIME_MULT 2 /* Undo fail if master is back. */
+#define CLUSTER_MF_TIMEOUT 5000 /* Milliseconds to do a manual failover. */
+#define CLUSTER_MF_PAUSE_MULT 2 /* Master pause manual failover mult. */
+#define CLUSTER_SLAVE_MIGRATION_DELAY 5000 /* Delay for slave migration. */
+
+/* Redirection errors returned by getNodeByQuery(). */
+#define CLUSTER_REDIR_NONE 0 /* Node can serve the request. */
+#define CLUSTER_REDIR_CROSS_SLOT 1 /* -CROSSSLOT request. */
+#define CLUSTER_REDIR_UNSTABLE 2 /* -TRYAGAIN redirection required */
+#define CLUSTER_REDIR_ASK 3 /* -ASK redirection required. */
+#define CLUSTER_REDIR_MOVED 4 /* -MOVED redirection required. */
+#define CLUSTER_REDIR_DOWN_STATE 5 /* -CLUSTERDOWN, global state. */
+#define CLUSTER_REDIR_DOWN_UNBOUND 6 /* -CLUSTERDOWN, unbound slot. */
+#define CLUSTER_REDIR_DOWN_RO_STATE 7 /* -CLUSTERDOWN, allow reads. */
+
+struct clusterNode;
+
+/* clusterLink encapsulates everything needed to talk with a remote node. */
+typedef struct clusterLink {
+ mstime_t ctime; /* Link creation time */
+ connection *conn; /* Connection to remote node */
+ sds sndbuf; /* Packet send buffer */
+ char *rcvbuf; /* Packet reception buffer */
+ size_t rcvbuf_len; /* Used size of rcvbuf */
+ size_t rcvbuf_alloc; /* Allocated size of rcvbuf */
+ struct clusterNode *node; /* Node related to this link. Initialized to NULL when unknown */
+ int inbound; /* 1 if this link is an inbound link accepted from the related node */
+} clusterLink;
+
+/* Cluster node flags and macros. */
+#define CLUSTER_NODE_MASTER 1 /* The node is a master */
+#define CLUSTER_NODE_SLAVE 2 /* The node is a slave */
+#define CLUSTER_NODE_PFAIL 4 /* Failure? Need acknowledge */
+#define CLUSTER_NODE_FAIL 8 /* The node is believed to be malfunctioning */
+#define CLUSTER_NODE_MYSELF 16 /* This node is myself */
+#define CLUSTER_NODE_HANDSHAKE 32 /* We have still to exchange the first ping */
+#define CLUSTER_NODE_NOADDR 64 /* We don't know the address of this node */
+#define CLUSTER_NODE_MEET 128 /* Send a MEET message to this node */
+#define CLUSTER_NODE_MIGRATE_TO 256 /* Master eligible for replica migration. */
+#define CLUSTER_NODE_NOFAILOVER 512 /* Slave will not try to failover. */
+#define CLUSTER_NODE_NULL_NAME "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"
+
+#define nodeIsMaster(n) ((n)->flags & CLUSTER_NODE_MASTER)
+#define nodeIsSlave(n) ((n)->flags & CLUSTER_NODE_SLAVE)
+#define nodeInHandshake(n) ((n)->flags & CLUSTER_NODE_HANDSHAKE)
+#define nodeHasAddr(n) (!((n)->flags & CLUSTER_NODE_NOADDR))
+#define nodeWithoutAddr(n) ((n)->flags & CLUSTER_NODE_NOADDR)
+#define nodeTimedOut(n) ((n)->flags & CLUSTER_NODE_PFAIL)
+#define nodeFailed(n) ((n)->flags & CLUSTER_NODE_FAIL)
+#define nodeCantFailover(n) ((n)->flags & CLUSTER_NODE_NOFAILOVER)
+
+/* Reasons why a slave is not able to failover. */
+#define CLUSTER_CANT_FAILOVER_NONE 0
+#define CLUSTER_CANT_FAILOVER_DATA_AGE 1
+#define CLUSTER_CANT_FAILOVER_WAITING_DELAY 2
+#define CLUSTER_CANT_FAILOVER_EXPIRED 3
+#define CLUSTER_CANT_FAILOVER_WAITING_VOTES 4
+#define CLUSTER_CANT_FAILOVER_RELOG_PERIOD (60*5) /* seconds. */
+
+/* clusterState todo_before_sleep flags. */
+#define CLUSTER_TODO_HANDLE_FAILOVER (1<<0)
+#define CLUSTER_TODO_UPDATE_STATE (1<<1)
+#define CLUSTER_TODO_SAVE_CONFIG (1<<2)
+#define CLUSTER_TODO_FSYNC_CONFIG (1<<3)
+#define CLUSTER_TODO_HANDLE_MANUALFAILOVER (1<<4)
+
+/* Message types.
+ *
+ * Note that the PING, PONG and MEET messages are actually the same exact
+ * kind of packet. PONG is the reply to ping, in the exact format as a PING,
+ * while MEET is a special PING that forces the receiver to add the sender
+ * as a node (if it is not already in the list). */
+#define CLUSTERMSG_TYPE_PING 0 /* Ping */
+#define CLUSTERMSG_TYPE_PONG 1 /* Pong (reply to Ping) */
+#define CLUSTERMSG_TYPE_MEET 2 /* Meet "let's join" message */
+#define CLUSTERMSG_TYPE_FAIL 3 /* Mark node xxx as failing */
+#define CLUSTERMSG_TYPE_PUBLISH 4 /* Pub/Sub Publish propagation */
+#define CLUSTERMSG_TYPE_FAILOVER_AUTH_REQUEST 5 /* May I failover? */
+#define CLUSTERMSG_TYPE_FAILOVER_AUTH_ACK 6 /* Yes, you have my vote */
+#define CLUSTERMSG_TYPE_UPDATE 7 /* Another node slots configuration */
+#define CLUSTERMSG_TYPE_MFSTART 8 /* Pause clients for manual failover */
+#define CLUSTERMSG_TYPE_MODULE 9 /* Module cluster API message. */
+#define CLUSTERMSG_TYPE_PUBLISHSHARD 10 /* Pub/Sub Publish shard propagation */
+#define CLUSTERMSG_TYPE_COUNT 11 /* Total number of message types. */
+
+/* Flags that a module can set in order to prevent certain Redis Cluster
+ * features to be enabled. Useful when implementing a different distributed
+ * system on top of Redis Cluster message bus, using modules. */
+#define CLUSTER_MODULE_FLAG_NONE 0
+#define CLUSTER_MODULE_FLAG_NO_FAILOVER (1<<1)
+#define CLUSTER_MODULE_FLAG_NO_REDIRECTION (1<<2)
+
+/* This structure represent elements of node->fail_reports. */
+typedef struct clusterNodeFailReport {
+ struct clusterNode *node; /* Node reporting the failure condition. */
+ mstime_t time; /* Time of the last report from this node. */
+} clusterNodeFailReport;
+
+typedef struct clusterNode {
+ mstime_t ctime; /* Node object creation time. */
+ char name[CLUSTER_NAMELEN]; /* Node name, hex string, sha1-size */
+ int flags; /* CLUSTER_NODE_... */
+ uint64_t configEpoch; /* Last configEpoch observed for this node */
+ unsigned char slots[CLUSTER_SLOTS/8]; /* slots handled by this node */
+ uint16_t *slot_info_pairs; /* Slots info represented as (start/end) pair (consecutive index). */
+ int slot_info_pairs_count; /* Used number of slots in slot_info_pairs */
+ int numslots; /* Number of slots handled by this node */
+ int numslaves; /* Number of slave nodes, if this is a master */
+ struct clusterNode **slaves; /* pointers to slave nodes */
+ struct clusterNode *slaveof; /* pointer to the master node. Note that it
+ may be NULL even if the node is a slave
+ if we don't have the master node in our
+ tables. */
+ unsigned long long last_in_ping_gossip; /* The number of the last carried in the ping gossip section */
+ mstime_t ping_sent; /* Unix time we sent latest ping */
+ mstime_t pong_received; /* Unix time we received the pong */
+ mstime_t data_received; /* Unix time we received any data */
+ mstime_t fail_time; /* Unix time when FAIL flag was set */
+ mstime_t voted_time; /* Last time we voted for a slave of this master */
+ mstime_t repl_offset_time; /* Unix time we received offset for this node */
+ mstime_t orphaned_time; /* Starting time of orphaned master condition */
+ long long repl_offset; /* Last known repl offset for this node. */
+ char ip[NET_IP_STR_LEN]; /* Latest known IP address of this node */
+ sds hostname; /* The known hostname for this node */
+ int port; /* Latest known clients port (TLS or plain). */
+ int pport; /* Latest known clients plaintext port. Only used
+ if the main clients port is for TLS. */
+ int cport; /* Latest known cluster port of this node. */
+ clusterLink *link; /* TCP/IP link established toward this node */
+ clusterLink *inbound_link; /* TCP/IP link accepted from this node */
+ list *fail_reports; /* List of nodes signaling this as failing */
+} clusterNode;
+
+/* Slot to keys for a single slot. The keys in the same slot are linked together
+ * using dictEntry metadata. */
+typedef struct slotToKeys {
+ uint64_t count; /* Number of keys in the slot. */
+ dictEntry *head; /* The first key-value entry in the slot. */
+} slotToKeys;
+
+/* Slot to keys mapping for all slots, opaque outside this file. */
+struct clusterSlotToKeyMapping {
+ slotToKeys by_slot[CLUSTER_SLOTS];
+};
+
+/* Dict entry metadata for cluster mode, used for the Slot to Key API to form a
+ * linked list of the entries belonging to the same slot. */
+typedef struct clusterDictEntryMetadata {
+ dictEntry *prev; /* Prev entry with key in the same slot */
+ dictEntry *next; /* Next entry with key in the same slot */
+} clusterDictEntryMetadata;
+
+
+typedef struct clusterState {
+ clusterNode *myself; /* This node */
+ uint64_t currentEpoch;
+ int state; /* CLUSTER_OK, CLUSTER_FAIL, ... */
+ int size; /* Num of master nodes with at least one slot */
+ dict *nodes; /* Hash table of name -> clusterNode structures */
+ dict *nodes_black_list; /* Nodes we don't re-add for a few seconds. */
+ clusterNode *migrating_slots_to[CLUSTER_SLOTS];
+ clusterNode *importing_slots_from[CLUSTER_SLOTS];
+ clusterNode *slots[CLUSTER_SLOTS];
+ rax *slots_to_channels;
+ /* The following fields are used to take the slave state on elections. */
+ mstime_t failover_auth_time; /* Time of previous or next election. */
+ int failover_auth_count; /* Number of votes received so far. */
+ int failover_auth_sent; /* True if we already asked for votes. */
+ int failover_auth_rank; /* This slave rank for current auth request. */
+ uint64_t failover_auth_epoch; /* Epoch of the current election. */
+ int cant_failover_reason; /* Why a slave is currently not able to
+ failover. See the CANT_FAILOVER_* macros. */
+ /* Manual failover state in common. */
+ mstime_t mf_end; /* Manual failover time limit (ms unixtime).
+ It is zero if there is no MF in progress. */
+ /* Manual failover state of master. */
+ clusterNode *mf_slave; /* Slave performing the manual failover. */
+ /* Manual failover state of slave. */
+ long long mf_master_offset; /* Master offset the slave needs to start MF
+ or -1 if still not received. */
+ int mf_can_start; /* If non-zero signal that the manual failover
+ can start requesting masters vote. */
+ /* The following fields are used by masters to take state on elections. */
+ uint64_t lastVoteEpoch; /* Epoch of the last vote granted. */
+ int todo_before_sleep; /* Things to do in clusterBeforeSleep(). */
+ /* Stats */
+ /* Messages received and sent by type. */
+ long long stats_bus_messages_sent[CLUSTERMSG_TYPE_COUNT];
+ long long stats_bus_messages_received[CLUSTERMSG_TYPE_COUNT];
+ long long stats_pfail_nodes; /* Number of nodes in PFAIL status,
+ excluding nodes without address. */
+ unsigned long long stat_cluster_links_buffer_limit_exceeded; /* Total number of cluster links freed due to exceeding buffer limit */
+
+ /* Bit map for slots that are no longer claimed by the owner in cluster PING
+ * messages. During slot migration, the owner will stop claiming the slot after
+ * the ownership transfer. Set the bit corresponding to the slot when a node
+ * stops claiming the slot. This prevents spreading incorrect information (that
+ * source still owns the slot) using UPDATE messages. */
+ unsigned char owner_not_claiming_slot[CLUSTER_SLOTS / 8];
+} clusterState;
+
+/* Redis cluster messages header */
+
+/* Initially we don't know our "name", but we'll find it once we connect
+ * to the first node, using the getsockname() function. Then we'll use this
+ * address for all the next messages. */
+typedef struct {
+ char nodename[CLUSTER_NAMELEN];
+ uint32_t ping_sent;
+ uint32_t pong_received;
+ char ip[NET_IP_STR_LEN]; /* IP address last time it was seen */
+ uint16_t port; /* base port last time it was seen */
+ uint16_t cport; /* cluster port last time it was seen */
+ uint16_t flags; /* node->flags copy */
+ uint16_t pport; /* plaintext-port, when base port is TLS */
+ uint16_t notused1;
+} clusterMsgDataGossip;
+
+typedef struct {
+ char nodename[CLUSTER_NAMELEN];
+} clusterMsgDataFail;
+
+typedef struct {
+ uint32_t channel_len;
+ uint32_t message_len;
+ unsigned char bulk_data[8]; /* 8 bytes just as placeholder. */
+} clusterMsgDataPublish;
+
+typedef struct {
+ uint64_t configEpoch; /* Config epoch of the specified instance. */
+ char nodename[CLUSTER_NAMELEN]; /* Name of the slots owner. */
+ unsigned char slots[CLUSTER_SLOTS/8]; /* Slots bitmap. */
+} clusterMsgDataUpdate;
+
+typedef struct {
+ uint64_t module_id; /* ID of the sender module. */
+ uint32_t len; /* ID of the sender module. */
+ uint8_t type; /* Type from 0 to 255. */
+ unsigned char bulk_data[3]; /* 3 bytes just as placeholder. */
+} clusterMsgModule;
+
+/* The cluster supports optional extension messages that can be sent
+ * along with ping/pong/meet messages to give additional info in a
+ * consistent manner. */
+typedef enum {
+ CLUSTERMSG_EXT_TYPE_HOSTNAME,
+} clusterMsgPingtypes;
+
+/* Helper function for making sure extensions are eight byte aligned. */
+#define EIGHT_BYTE_ALIGN(size) ((((size) + 7) / 8) * 8)
+
+typedef struct {
+ char hostname[1]; /* The announced hostname, ends with \0. */
+} clusterMsgPingExtHostname;
+
+typedef struct {
+ uint32_t length; /* Total length of this extension message (including this header) */
+ uint16_t type; /* Type of this extension message (see clusterMsgPingExtTypes) */
+ uint16_t unused; /* 16 bits of padding to make this structure 8 byte aligned. */
+ union {
+ clusterMsgPingExtHostname hostname;
+ } ext[]; /* Actual extension information, formatted so that the data is 8
+ * byte aligned, regardless of its content. */
+} clusterMsgPingExt;
+
+union clusterMsgData {
+ /* PING, MEET and PONG */
+ struct {
+ /* Array of N clusterMsgDataGossip structures */
+ clusterMsgDataGossip gossip[1];
+ /* Extension data that can optionally be sent for ping/meet/pong
+ * messages. We can't explicitly define them here though, since
+ * the gossip array isn't the real length of the gossip data. */
+ } ping;
+
+ /* FAIL */
+ struct {
+ clusterMsgDataFail about;
+ } fail;
+
+ /* PUBLISH */
+ struct {
+ clusterMsgDataPublish msg;
+ } publish;
+
+ /* UPDATE */
+ struct {
+ clusterMsgDataUpdate nodecfg;
+ } update;
+
+ /* MODULE */
+ struct {
+ clusterMsgModule msg;
+ } module;
+};
+
+#define CLUSTER_PROTO_VER 1 /* Cluster bus protocol version. */
+
+typedef struct {
+ char sig[4]; /* Signature "RCmb" (Redis Cluster message bus). */
+ uint32_t totlen; /* Total length of this message */
+ uint16_t ver; /* Protocol version, currently set to 1. */
+ uint16_t port; /* TCP base port number. */
+ uint16_t type; /* Message type */
+ uint16_t count; /* Only used for some kind of messages. */
+ uint64_t currentEpoch; /* The epoch accordingly to the sending node. */
+ uint64_t configEpoch; /* The config epoch if it's a master, or the last
+ epoch advertised by its master if it is a
+ slave. */
+ uint64_t offset; /* Master replication offset if node is a master or
+ processed replication offset if node is a slave. */
+ char sender[CLUSTER_NAMELEN]; /* Name of the sender node */
+ unsigned char myslots[CLUSTER_SLOTS/8];
+ char slaveof[CLUSTER_NAMELEN];
+ char myip[NET_IP_STR_LEN]; /* Sender IP, if not all zeroed. */
+ uint16_t extensions; /* Number of extensions sent along with this packet. */
+ char notused1[30]; /* 30 bytes reserved for future usage. */
+ uint16_t pport; /* Sender TCP plaintext port, if base port is TLS */
+ uint16_t cport; /* Sender TCP cluster bus port */
+ uint16_t flags; /* Sender node flags */
+ unsigned char state; /* Cluster state from the POV of the sender */
+ unsigned char mflags[3]; /* Message flags: CLUSTERMSG_FLAG[012]_... */
+ union clusterMsgData data;
+} clusterMsg;
+
+/* clusterMsg defines the gossip wire protocol exchanged among Redis cluster
+ * members, which can be running different versions of redis-server bits,
+ * especially during cluster rolling upgrades.
+ *
+ * Therefore, fields in this struct should remain at the same offset from
+ * release to release. The static asserts below ensures that incompatible
+ * changes in clusterMsg be caught at compile time.
+ */
+
+static_assert(offsetof(clusterMsg, sig) == 0, "unexpected field offset");
+static_assert(offsetof(clusterMsg, totlen) == 4, "unexpected field offset");
+static_assert(offsetof(clusterMsg, ver) == 8, "unexpected field offset");
+static_assert(offsetof(clusterMsg, port) == 10, "unexpected field offset");
+static_assert(offsetof(clusterMsg, type) == 12, "unexpected field offset");
+static_assert(offsetof(clusterMsg, count) == 14, "unexpected field offset");
+static_assert(offsetof(clusterMsg, currentEpoch) == 16, "unexpected field offset");
+static_assert(offsetof(clusterMsg, configEpoch) == 24, "unexpected field offset");
+static_assert(offsetof(clusterMsg, offset) == 32, "unexpected field offset");
+static_assert(offsetof(clusterMsg, sender) == 40, "unexpected field offset");
+static_assert(offsetof(clusterMsg, myslots) == 80, "unexpected field offset");
+static_assert(offsetof(clusterMsg, slaveof) == 2128, "unexpected field offset");
+static_assert(offsetof(clusterMsg, myip) == 2168, "unexpected field offset");
+static_assert(offsetof(clusterMsg, extensions) == 2214, "unexpected field offset");
+static_assert(offsetof(clusterMsg, notused1) == 2216, "unexpected field offset");
+static_assert(offsetof(clusterMsg, pport) == 2246, "unexpected field offset");
+static_assert(offsetof(clusterMsg, cport) == 2248, "unexpected field offset");
+static_assert(offsetof(clusterMsg, flags) == 2250, "unexpected field offset");
+static_assert(offsetof(clusterMsg, state) == 2252, "unexpected field offset");
+static_assert(offsetof(clusterMsg, mflags) == 2253, "unexpected field offset");
+static_assert(offsetof(clusterMsg, data) == 2256, "unexpected field offset");
+
+#define CLUSTERMSG_MIN_LEN (sizeof(clusterMsg)-sizeof(union clusterMsgData))
+
+/* Message flags better specify the packet content or are used to
+ * provide some information about the node state. */
+#define CLUSTERMSG_FLAG0_PAUSED (1<<0) /* Master paused for manual failover. */
+#define CLUSTERMSG_FLAG0_FORCEACK (1<<1) /* Give ACK to AUTH_REQUEST even if
+ master is up. */
+#define CLUSTERMSG_FLAG0_EXT_DATA (1<<2) /* Message contains extension data */
+
+/* ---------------------- API exported outside cluster.c -------------------- */
+void clusterInit(void);
+void clusterCron(void);
+void clusterBeforeSleep(void);
+clusterNode *getNodeByQuery(client *c, struct redisCommand *cmd, robj **argv, int argc, int *hashslot, int *ask);
+int verifyClusterNodeId(const char *name, int length);
+clusterNode *clusterLookupNode(const char *name, int length);
+int clusterRedirectBlockedClientIfNeeded(client *c);
+void clusterRedirectClient(client *c, clusterNode *n, int hashslot, int error_code);
+void migrateCloseTimedoutSockets(void);
+int verifyClusterConfigWithData(void);
+unsigned long getClusterConnectionsCount(void);
+int clusterSendModuleMessageToTarget(const char *target, uint64_t module_id, uint8_t type, const char *payload, uint32_t len);
+void clusterPropagatePublish(robj *channel, robj *message, int sharded);
+unsigned int keyHashSlot(char *key, int keylen);
+void slotToKeyAddEntry(dictEntry *entry, redisDb *db);
+void slotToKeyDelEntry(dictEntry *entry, redisDb *db);
+void slotToKeyReplaceEntry(dictEntry *entry, redisDb *db);
+void slotToKeyInit(redisDb *db);
+void slotToKeyFlush(redisDb *db);
+void slotToKeyDestroy(redisDb *db);
+void clusterUpdateMyselfFlags(void);
+void clusterUpdateMyselfIp(void);
+void slotToChannelAdd(sds channel);
+void slotToChannelDel(sds channel);
+void clusterUpdateMyselfHostname(void);
+void clusterUpdateMyselfAnnouncedPorts(void);
+void freeClusterLink(clusterLink *link);
+
+#endif /* __CLUSTER_H */