* POSSIBILITY OF SUCH DAMAGE.
*/
-#define REDIS_VERSION "1.3.0"
+#define REDIS_VERSION "1.3.1"
#include "fmacros.h"
#include "config.h"
#define REDIS_MASTER 4 /* This client is a master server */
#define REDIS_MONITOR 8 /* This client is a slave monitor, see MONITOR */
#define REDIS_MULTI 16 /* This client is in a MULTI context */
+#define REDIS_BLOCKED 32 /* The client is waiting in a blocking operation */
/* Slave replication state - slave side */
#define REDIS_REPL_NONE 0 /* No active replication */
} while(0);
typedef struct redisDb {
- dict *dict;
- dict *expires;
+ dict *dict; /* The keyspace for this DB */
+ dict *expires; /* Timeout of keys with a timeout set */
+ dict *blockingkeys; /* Keys with clients waiting for data (BLPOP) */
int id;
} redisDb;
long repldboff; /* replication DB file offset */
off_t repldbsize; /* replication DB file size */
multiState mstate; /* MULTI/EXEC state */
+ robj **blockingkeys; /* The key we waiting to terminate a blocking
+ * operation such as BLPOP. Otherwise NULL. */
+ int blockingkeysnum; /* Number of blocking keys */
+ time_t blockingto; /* Blocking operation timeout. If UNIX current time
+ * is >= blockingto then the operation timed out. */
} redisClient;
struct saveparam {
int port;
int fd;
redisDb *db;
- dict *sharingpool;
+ dict *sharingpool; /* Poll used for object sharing */
unsigned int sharingpoolsize;
long long dirty; /* changes to DB from the last save */
list *clients;
int replstate;
unsigned int maxclients;
unsigned long maxmemory;
+ unsigned int blockedclients;
/* Sort parameters - qsort_r() is only available under BSD so we
* have to take this state global, in order to pass it to sortCompare() */
int sort_desc;
static void initClientMultiState(redisClient *c);
static void freeClientMultiState(redisClient *c);
static void queueMultiCommand(redisClient *c, struct redisCommand *cmd);
+static void unblockClient(redisClient *c);
+static int handleClientsWaitingListPush(redisClient *c, robj *key, robj *ele);
static void authCommand(redisClient *c);
static void pingCommand(redisClient *c);
static void zremrangebyscoreCommand(redisClient *c);
static void multiCommand(redisClient *c);
static void execCommand(redisClient *c);
+static void blpopCommand(redisClient *c);
+static void brpopCommand(redisClient *c);
/*================================= Globals ================================= */
{"lpush",lpushCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM},
{"rpop",rpopCommand,2,REDIS_CMD_INLINE},
{"lpop",lpopCommand,2,REDIS_CMD_INLINE},
+ {"brpop",brpopCommand,-3,REDIS_CMD_INLINE},
+ {"blpop",blpopCommand,-3,REDIS_CMD_INLINE},
{"llen",llenCommand,2,REDIS_CMD_INLINE},
{"lindex",lindexCommand,3,REDIS_CMD_INLINE},
{"lset",lsetCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM},
zfree(val);
}
+static void dictListDestructor(void *privdata, void *val)
+{
+ DICT_NOTUSED(privdata);
+ listRelease((list*)val);
+}
+
static int sdsDictKeyCompare(void *privdata, const void *key1,
const void *key2)
{
dictRedisObjectDestructor /* val destructor */
};
+/* Keylist hash table type has unencoded redis objects as keys and
+ * lists as values. It's used for blocking operations (BLPOP) */
+static dictType keylistDictType = {
+ dictObjHash, /* hash function */
+ NULL, /* key dup */
+ NULL, /* val dup */
+ dictObjKeyCompare, /* key compare */
+ dictRedisObjectDestructor, /* key destructor */
+ dictListDestructor /* val destructor */
+};
+
/* ========================= Random utility functions ======================= */
/* Redis generally does not try to recover from out of memory conditions
listRewind(server.clients);
while ((ln = listYield(server.clients)) != NULL) {
c = listNodeValue(ln);
- if (!(c->flags & REDIS_SLAVE) && /* no timeout for slaves */
+ if (server.maxidletime &&
+ !(c->flags & REDIS_SLAVE) && /* no timeout for slaves */
!(c->flags & REDIS_MASTER) && /* no timeout for masters */
- (now - c->lastinteraction > server.maxidletime)) {
+ (now - c->lastinteraction > server.maxidletime))
+ {
redisLog(REDIS_DEBUG,"Closing idle client");
freeClient(c);
+ } else if (c->flags & REDIS_BLOCKED) {
+ if (c->blockingto != 0 && c->blockingto < now) {
+ addReply(c,shared.nullmultibulk);
+ unblockClient(c);
+ }
}
}
}
}
/* Close connections of timedout clients */
- if (server.maxidletime && !(loops % 10))
+ if ((server.maxidletime && !(loops % 10)) || server.blockedclients)
closeTimedoutClients();
/* Check if a background saving or AOF rewrite in progress terminated */
server.rdbcompression = 1;
server.sharingpoolsize = 1024;
server.maxclients = 0;
+ server.blockedclients = 0;
server.maxmemory = 0;
resetServerSaveParams();
for (j = 0; j < server.dbnum; j++) {
server.db[j].dict = dictCreate(&hashDictType,NULL);
server.db[j].expires = dictCreate(&setDictType,NULL);
+ server.db[j].blockingkeys = dictCreate(&keylistDictType,NULL);
server.db[j].id = j;
}
server.cronloops = 0;
static void freeClient(redisClient *c) {
listNode *ln;
+ /* Note that if the client we are freeing is blocked into a blocking
+ * call, we have to set querybuf to NULL *before* to call unblockClient()
+ * to avoid processInputBuffer() will get called. Also it is important
+ * to remove the file events after this, because this call adds
+ * the READABLE event. */
+ sdsfree(c->querybuf);
+ c->querybuf = NULL;
+ if (c->flags & REDIS_BLOCKED)
+ unblockClient(c);
+
aeDeleteFileEvent(server.el,c->fd,AE_READABLE);
aeDeleteFileEvent(server.el,c->fd,AE_WRITABLE);
- sdsfree(c->querybuf);
listRelease(c->reply);
freeClientArgv(c);
close(c->fd);
static void processInputBuffer(redisClient *c) {
again:
+ /* Before to process the input buffer, make sure the client is not
+ * waitig for a blocking operation such as BLPOP. Note that the first
+ * iteration the client is never blocked, otherwise the processInputBuffer
+ * would not be called at all, but after the execution of the first commands
+ * in the input buffer the client may be blocked, and the "goto again"
+ * will try to reiterate. The following line will make it return asap. */
+ if (c->flags & REDIS_BLOCKED) return;
if (c->bulklen == -1) {
/* Read the first line of the query */
char *p = strchr(c->querybuf,'\n');
c->authenticated = 0;
c->replstate = REDIS_REPL_NONE;
c->reply = listCreate();
+ c->blockingkeys = NULL;
+ c->blockingkeysnum = 0;
listSetFreeMethod(c->reply,decrRefCount);
listSetDupMethod(c->reply,dupClientReplyValue);
if (aeCreateFileEvent(server.el, c->fd, AE_READABLE,
}
}
-/*============================ DB saving/loading ============================ */
+/*============================ RDB saving/loading =========================== */
static int rdbSaveType(FILE *fp, unsigned char type) {
if (fwrite(&type,1,1,fp) == 0) return -1;
return 0;
}
+/* Save a Redis object. */
+static int rdbSaveObject(FILE *fp, robj *o) {
+ if (o->type == REDIS_STRING) {
+ /* Save a string value */
+ if (rdbSaveStringObject(fp,o) == -1) return -1;
+ } else if (o->type == REDIS_LIST) {
+ /* Save a list value */
+ list *list = o->ptr;
+ listNode *ln;
+
+ listRewind(list);
+ if (rdbSaveLen(fp,listLength(list)) == -1) return -1;
+ while((ln = listYield(list))) {
+ robj *eleobj = listNodeValue(ln);
+
+ if (rdbSaveStringObject(fp,eleobj) == -1) return -1;
+ }
+ } else if (o->type == REDIS_SET) {
+ /* Save a set value */
+ dict *set = o->ptr;
+ dictIterator *di = dictGetIterator(set);
+ dictEntry *de;
+
+ if (rdbSaveLen(fp,dictSize(set)) == -1) return -1;
+ while((de = dictNext(di)) != NULL) {
+ robj *eleobj = dictGetEntryKey(de);
+
+ if (rdbSaveStringObject(fp,eleobj) == -1) return -1;
+ }
+ dictReleaseIterator(di);
+ } else if (o->type == REDIS_ZSET) {
+ /* Save a set value */
+ zset *zs = o->ptr;
+ dictIterator *di = dictGetIterator(zs->dict);
+ dictEntry *de;
+
+ if (rdbSaveLen(fp,dictSize(zs->dict)) == -1) return -1;
+ while((de = dictNext(di)) != NULL) {
+ robj *eleobj = dictGetEntryKey(de);
+ double *score = dictGetEntryVal(de);
+
+ if (rdbSaveStringObject(fp,eleobj) == -1) return -1;
+ if (rdbSaveDoubleValue(fp,*score) == -1) return -1;
+ }
+ dictReleaseIterator(di);
+ } else {
+ redisAssert(0 != 0);
+ }
+ return 0;
+}
+
+/* Return the length the object will have on disk if saved with
+ * the rdbSaveObject() function. Currently we use a trick to get
+ * this length with very little changes to the code. In the future
+ * we could switch to a faster solution. */
+static off_t rdbSavedObjectLen(robj *o) {
+ static FILE *fp = NULL;
+
+ if (fp == NULL) fp = fopen("/dev/null","w");
+ assert(fp != NULL);
+
+ rewind(fp);
+ assert(rdbSaveObject(fp,o) != 1);
+ return ftello(fp);
+}
+
/* Save the DB on disk. Return REDIS_ERR on error, REDIS_OK on success */
static int rdbSave(char *filename) {
dictIterator *di = NULL;
/* Save the key and associated value */
if (rdbSaveType(fp,o->type) == -1) goto werr;
if (rdbSaveStringObject(fp,key) == -1) goto werr;
- if (o->type == REDIS_STRING) {
- /* Save a string value */
- if (rdbSaveStringObject(fp,o) == -1) goto werr;
- } else if (o->type == REDIS_LIST) {
- /* Save a list value */
- list *list = o->ptr;
- listNode *ln;
-
- listRewind(list);
- if (rdbSaveLen(fp,listLength(list)) == -1) goto werr;
- while((ln = listYield(list))) {
- robj *eleobj = listNodeValue(ln);
-
- if (rdbSaveStringObject(fp,eleobj) == -1) goto werr;
- }
- } else if (o->type == REDIS_SET) {
- /* Save a set value */
- dict *set = o->ptr;
- dictIterator *di = dictGetIterator(set);
- dictEntry *de;
-
- if (rdbSaveLen(fp,dictSize(set)) == -1) goto werr;
- while((de = dictNext(di)) != NULL) {
- robj *eleobj = dictGetEntryKey(de);
-
- if (rdbSaveStringObject(fp,eleobj) == -1) goto werr;
- }
- dictReleaseIterator(di);
- } else if (o->type == REDIS_ZSET) {
- /* Save a set value */
- zset *zs = o->ptr;
- dictIterator *di = dictGetIterator(zs->dict);
- dictEntry *de;
-
- if (rdbSaveLen(fp,dictSize(zs->dict)) == -1) goto werr;
- while((de = dictNext(di)) != NULL) {
- robj *eleobj = dictGetEntryKey(de);
- double *score = dictGetEntryVal(de);
-
- if (rdbSaveStringObject(fp,eleobj) == -1) goto werr;
- if (rdbSaveDoubleValue(fp,*score) == -1) goto werr;
- }
- dictReleaseIterator(di);
- } else {
- redisAssert(0 != 0);
- }
+ /* Save the actual value */
+ if (rdbSaveObject(fp,o) == -1) goto werr;
}
dictReleaseIterator(di);
}
lobj = lookupKeyWrite(c->db,c->argv[1]);
if (lobj == NULL) {
+ if (handleClientsWaitingListPush(c,c->argv[1],c->argv[2])) {
+ addReply(c,shared.ok);
+ return;
+ }
lobj = createListObject();
list = lobj->ptr;
if (where == REDIS_HEAD) {
addReply(c,shared.wrongtypeerr);
return;
}
+ if (handleClientsWaitingListPush(c,c->argv[1],c->argv[2])) {
+ addReply(c,shared.ok);
+ return;
+ }
list = lobj->ptr;
if (where == REDIS_HEAD) {
listAddNodeHead(list,c->argv[2]);
robj *ele = listNodeValue(ln);
list *dstlist;
- if (dobj == NULL) {
-
- /* Create the list if the key does not exist */
- dobj = createListObject();
- dictAdd(c->db->dict,c->argv[2],dobj);
- incrRefCount(c->argv[2]);
- } else if (dobj->type != REDIS_LIST) {
+ if (dobj && dobj->type != REDIS_LIST) {
addReply(c,shared.wrongtypeerr);
return;
}
- /* Add the element to the target list */
- dstlist = dobj->ptr;
- listAddNodeHead(dstlist,ele);
- incrRefCount(ele);
+
+ /* Add the element to the target list (unless it's directly
+ * passed to some BLPOP-ing client */
+ if (!handleClientsWaitingListPush(c,c->argv[2],ele)) {
+ if (dobj == NULL) {
+ /* Create the list if the key does not exist */
+ dobj = createListObject();
+ dictAdd(c->db->dict,c->argv[2],dobj);
+ incrRefCount(c->argv[2]);
+ }
+ dstlist = dobj->ptr;
+ listAddNodeHead(dstlist,ele);
+ incrRefCount(ele);
+ }
/* Send the element to the client as reply as well */
addReplyBulkLen(c,ele);
"uptime_in_days:%ld\r\n"
"connected_clients:%d\r\n"
"connected_slaves:%d\r\n"
+ "blocked_clients:%d\r\n"
"used_memory:%zu\r\n"
"changes_since_last_save:%lld\r\n"
"bgsave_in_progress:%d\r\n"
uptime/(3600*24),
listLength(server.clients)-listLength(server.slaves),
listLength(server.slaves),
+ server.blockedclients,
server.usedmemory,
server.dirty,
server.bgsavechildpid != -1,
c->flags &= (~REDIS_MULTI);
}
+/* =========================== Blocking Operations ========================= */
+
+/* Currently Redis blocking operations support is limited to list POP ops,
+ * so the current implementation is not fully generic, but it is also not
+ * completely specific so it will not require a rewrite to support new
+ * kind of blocking operations in the future.
+ *
+ * Still it's important to note that list blocking operations can be already
+ * used as a notification mechanism in order to implement other blocking
+ * operations at application level, so there must be a very strong evidence
+ * of usefulness and generality before new blocking operations are implemented.
+ *
+ * This is how the current blocking POP works, we use BLPOP as example:
+ * - If the user calls BLPOP and the key exists and contains a non empty list
+ * then LPOP is called instead. So BLPOP is semantically the same as LPOP
+ * if there is not to block.
+ * - If instead BLPOP is called and the key does not exists or the list is
+ * empty we need to block. In order to do so we remove the notification for
+ * new data to read in the client socket (so that we'll not serve new
+ * requests if the blocking request is not served). Also we put the client
+ * in a dictionary (db->blockingkeys) mapping keys to a list of clients
+ * blocking for this keys.
+ * - If a PUSH operation against a key with blocked clients waiting is
+ * performed, we serve the first in the list: basically instead to push
+ * the new element inside the list we return it to the (first / oldest)
+ * blocking client, unblock the client, and remove it form the list.
+ *
+ * The above comment and the source code should be enough in order to understand
+ * the implementation and modify / fix it later.
+ */
+
+/* Set a client in blocking mode for the specified key, with the specified
+ * timeout */
+static void blockForKeys(redisClient *c, robj **keys, int numkeys, time_t timeout) {
+ dictEntry *de;
+ list *l;
+ int j;
+
+ c->blockingkeys = zmalloc(sizeof(robj*)*numkeys);
+ c->blockingkeysnum = numkeys;
+ c->blockingto = timeout;
+ for (j = 0; j < numkeys; j++) {
+ /* Add the key in the client structure, to map clients -> keys */
+ c->blockingkeys[j] = keys[j];
+ incrRefCount(keys[j]);
+
+ /* And in the other "side", to map keys -> clients */
+ de = dictFind(c->db->blockingkeys,keys[j]);
+ if (de == NULL) {
+ int retval;
+
+ /* For every key we take a list of clients blocked for it */
+ l = listCreate();
+ retval = dictAdd(c->db->blockingkeys,keys[j],l);
+ incrRefCount(keys[j]);
+ assert(retval == DICT_OK);
+ } else {
+ l = dictGetEntryVal(de);
+ }
+ listAddNodeTail(l,c);
+ }
+ /* Mark the client as a blocked client */
+ c->flags |= REDIS_BLOCKED;
+ aeDeleteFileEvent(server.el,c->fd,AE_READABLE);
+ server.blockedclients++;
+}
+
+/* Unblock a client that's waiting in a blocking operation such as BLPOP */
+static void unblockClient(redisClient *c) {
+ dictEntry *de;
+ list *l;
+ int j;
+
+ assert(c->blockingkeys != NULL);
+ /* The client may wait for multiple keys, so unblock it for every key. */
+ for (j = 0; j < c->blockingkeysnum; j++) {
+ /* Remove this client from the list of clients waiting for this key. */
+ de = dictFind(c->db->blockingkeys,c->blockingkeys[j]);
+ assert(de != NULL);
+ l = dictGetEntryVal(de);
+ listDelNode(l,listSearchKey(l,c));
+ /* If the list is empty we need to remove it to avoid wasting memory */
+ if (listLength(l) == 0)
+ dictDelete(c->db->blockingkeys,c->blockingkeys[j]);
+ decrRefCount(c->blockingkeys[j]);
+ }
+ /* Cleanup the client structure */
+ zfree(c->blockingkeys);
+ c->blockingkeys = NULL;
+ c->flags &= (~REDIS_BLOCKED);
+ server.blockedclients--;
+ /* Ok now we are ready to get read events from socket, note that we
+ * can't trap errors here as it's possible that unblockClients() is
+ * called from freeClient() itself, and the only thing we can do
+ * if we failed to register the READABLE event is to kill the client.
+ * Still the following function should never fail in the real world as
+ * we are sure the file descriptor is sane, and we exit on out of mem. */
+ aeCreateFileEvent(server.el, c->fd, AE_READABLE, readQueryFromClient, c);
+ /* As a final step we want to process data if there is some command waiting
+ * in the input buffer. Note that this is safe even if unblockClient()
+ * gets called from freeClient() because freeClient() will be smart
+ * enough to call this function *after* c->querybuf was set to NULL. */
+ if (c->querybuf && sdslen(c->querybuf) > 0) processInputBuffer(c);
+}
+
+/* This should be called from any function PUSHing into lists.
+ * 'c' is the "pushing client", 'key' is the key it is pushing data against,
+ * 'ele' is the element pushed.
+ *
+ * If the function returns 0 there was no client waiting for a list push
+ * against this key.
+ *
+ * If the function returns 1 there was a client waiting for a list push
+ * against this key, the element was passed to this client thus it's not
+ * needed to actually add it to the list and the caller should return asap. */
+static int handleClientsWaitingListPush(redisClient *c, robj *key, robj *ele) {
+ struct dictEntry *de;
+ redisClient *receiver;
+ list *l;
+ listNode *ln;
+
+ de = dictFind(c->db->blockingkeys,key);
+ if (de == NULL) return 0;
+ l = dictGetEntryVal(de);
+ ln = listFirst(l);
+ assert(ln != NULL);
+ receiver = ln->value;
+
+ addReplySds(receiver,sdsnew("*2\r\n"));
+ addReplyBulkLen(receiver,key);
+ addReply(receiver,key);
+ addReply(receiver,shared.crlf);
+ addReplyBulkLen(receiver,ele);
+ addReply(receiver,ele);
+ addReply(receiver,shared.crlf);
+ unblockClient(receiver);
+ return 1;
+}
+
+/* Blocking RPOP/LPOP */
+static void blockingPopGenericCommand(redisClient *c, int where) {
+ robj *o;
+ time_t timeout;
+ int j;
+
+ for (j = 1; j < c->argc-1; j++) {
+ o = lookupKeyWrite(c->db,c->argv[j]);
+ if (o != NULL) {
+ if (o->type != REDIS_LIST) {
+ addReply(c,shared.wrongtypeerr);
+ return;
+ } else {
+ list *list = o->ptr;
+ if (listLength(list) != 0) {
+ /* If the list contains elements fall back to the usual
+ * non-blocking POP operation */
+ robj *argv[2], **orig_argv;
+ int orig_argc;
+
+ /* We need to alter the command arguments before to call
+ * popGenericCommand() as the command takes a single key. */
+ orig_argv = c->argv;
+ orig_argc = c->argc;
+ argv[1] = c->argv[j];
+ c->argv = argv;
+ c->argc = 2;
+
+ /* Also the return value is different, we need to output
+ * the multi bulk reply header and the key name. The
+ * "real" command will add the last element (the value)
+ * for us. If this souds like an hack to you it's just
+ * because it is... */
+ addReplySds(c,sdsnew("*2\r\n"));
+ addReplyBulkLen(c,argv[1]);
+ addReply(c,argv[1]);
+ addReply(c,shared.crlf);
+ popGenericCommand(c,where);
+
+ /* Fix the client structure with the original stuff */
+ c->argv = orig_argv;
+ c->argc = orig_argc;
+ return;
+ }
+ }
+ }
+ }
+ /* If the list is empty or the key does not exists we must block */
+ timeout = strtol(c->argv[c->argc-1]->ptr,NULL,10);
+ if (timeout > 0) timeout += time(NULL);
+ blockForKeys(c,c->argv+1,c->argc-2,timeout);
+}
+
+static void blpopCommand(redisClient *c) {
+ blockingPopGenericCommand(c,REDIS_HEAD);
+}
+
+static void brpopCommand(redisClient *c) {
+ blockingPopGenericCommand(c,REDIS_TAIL);
+}
+
/* =============================== Replication ============================= */
static int syncWrite(int fd, char *ptr, ssize_t size, int timeout) {
key = dictGetEntryKey(de);
val = dictGetEntryVal(de);
addReplySds(c,sdscatprintf(sdsempty(),
- "+Key at:%p refcount:%d, value at:%p refcount:%d encoding:%d\r\n",
+ "+Key at:%p refcount:%d, value at:%p refcount:%d encoding:%d serializedlength:%lld\r\n",
(void*)key, key->refcount, (void*)val, val->refcount,
- val->encoding));
+ val->encoding, rdbSavedObjectLen(val)));
} else {
addReplySds(c,sdsnew(
"-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT <key>|RELOAD]\r\n"));
#else
return (void*) uc->uc_mcontext->__ss.__eip;
#endif
-#elif defined(__i386__) || defined(__X86_64__) /* Linux x86 */
- return (void*) uc->uc_mcontext.gregs[REG_EIP];
+#elif defined(__i386__) || defined(__X86_64__) || defined(__x86_64__)
+ return (void*) uc->uc_mcontext.gregs[REG_EIP]; /* Linux 32/64 bit */
#elif defined(__ia64__) /* Linux IA64 */
return (void*) uc->uc_mcontext.sc_ip;
#else
redisLog(REDIS_WARNING,"%d redis-server %p %s + %d", i, trace[i], fn, (unsigned int)offset);
}
}
- // free(messages); Don't call free() with possibly corrupted memory.
+ /* free(messages); Don't call free() with possibly corrupted memory. */
exit(0);
}
projects / redis.git / blobdiff