Adding upstream version 5:7.2.4.upstream/5%7.2.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 202 insertions, 0 deletions

diff --git a/src/timeout.c b/src/timeout.c
new file mode 100644
index 0000000..eb971dc
--- /dev/null
+++ b/src/timeout.c
@@ -0,0 +1,202 @@
+/* Copyright (c) 2009-2020, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "server.h"
+#include "cluster.h"
+
+#include <math.h>
+
+/* ========================== Clients timeouts ============================= */
+
+/* Check if this blocked client timedout (does nothing if the client is
+ * not blocked right now). If so send a reply, unblock it, and return 1.
+ * Otherwise 0 is returned and no operation is performed. */
+int checkBlockedClientTimeout(client *c, mstime_t now) {
+    if (c->flags & CLIENT_BLOCKED &&
+        c->bstate.timeout != 0
+        && c->bstate.timeout < now)
+    {
+        /* Handle blocking operation specific timeout. */
+        unblockClientOnTimeout(c);
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+/* Check for timeouts. Returns non-zero if the client was terminated.
+ * The function gets the current time in milliseconds as argument since
+ * it gets called multiple times in a loop, so calling gettimeofday() for
+ * each iteration would be costly without any actual gain. */
+int clientsCronHandleTimeout(client *c, mstime_t now_ms) {
+    time_t now = now_ms/1000;
+
+    if (server.maxidletime &&
+        /* This handles the idle clients connection timeout if set. */
+        !(c->flags & CLIENT_SLAVE) &&   /* No timeout for slaves and monitors */
+        !mustObeyClient(c) &&         /* No timeout for masters and AOF */
+        !(c->flags & CLIENT_BLOCKED) && /* No timeout for BLPOP */
+        !(c->flags & CLIENT_PUBSUB) &&  /* No timeout for Pub/Sub clients */
+        (now - c->lastinteraction > server.maxidletime))
+    {
+        serverLog(LL_VERBOSE,"Closing idle client");
+        freeClient(c);
+        return 1;
+    } else if (c->flags & CLIENT_BLOCKED) {
+        /* Cluster: handle unblock & redirect of clients blocked
+         * into keys no longer served by this server. */
+        if (server.cluster_enabled) {
+            if (clusterRedirectBlockedClientIfNeeded(c))
+                unblockClientOnError(c, NULL);
+        }
+    }
+    return 0;
+}
+
+/* For blocked clients timeouts we populate a radix tree of 128 bit keys
+ * composed as such:
+ *
+ *  [8 byte big endian expire time]+[8 byte client ID]
+ *
+ * We don't do any cleanup in the Radix tree: when we run the clients that
+ * reached the timeout already, if they are no longer existing or no longer
+ * blocked with such timeout, we just go forward.
+ *
+ * Every time a client blocks with a timeout, we add the client in
+ * the tree. In beforeSleep() we call handleBlockedClientsTimeout() to run
+ * the tree and unblock the clients. */
+
+#define CLIENT_ST_KEYLEN 16    /* 8 bytes mstime + 8 bytes client ID. */
+
+/* Given client ID and timeout, write the resulting radix tree key in buf. */
+void encodeTimeoutKey(unsigned char *buf, uint64_t timeout, client *c) {
+    timeout = htonu64(timeout);
+    memcpy(buf,&timeout,sizeof(timeout));
+    memcpy(buf+8,&c,sizeof(c));
+    if (sizeof(c) == 4) memset(buf+12,0,4); /* Zero padding for 32bit target. */
+}
+
+/* Given a key encoded with encodeTimeoutKey(), resolve the fields and write
+ * the timeout into *toptr and the client pointer into *cptr. */
+void decodeTimeoutKey(unsigned char *buf, uint64_t *toptr, client **cptr) {
+    memcpy(toptr,buf,sizeof(*toptr));
+    *toptr = ntohu64(*toptr);
+    memcpy(cptr,buf+8,sizeof(*cptr));
+}
+
+/* Add the specified client id / timeout as a key in the radix tree we use
+ * to handle blocked clients timeouts. The client is not added to the list
+ * if its timeout is zero (block forever). */
+void addClientToTimeoutTable(client *c) {
+    if (c->bstate.timeout == 0) return;
+    uint64_t timeout = c->bstate.timeout;
+    unsigned char buf[CLIENT_ST_KEYLEN];
+    encodeTimeoutKey(buf,timeout,c);
+    if (raxTryInsert(server.clients_timeout_table,buf,sizeof(buf),NULL,NULL))
+        c->flags |= CLIENT_IN_TO_TABLE;
+}
+
+/* Remove the client from the table when it is unblocked for reasons
+ * different than timing out. */
+void removeClientFromTimeoutTable(client *c) {
+    if (!(c->flags & CLIENT_IN_TO_TABLE)) return;
+    c->flags &= ~CLIENT_IN_TO_TABLE;
+    uint64_t timeout = c->bstate.timeout;
+    unsigned char buf[CLIENT_ST_KEYLEN];
+    encodeTimeoutKey(buf,timeout,c);
+    raxRemove(server.clients_timeout_table,buf,sizeof(buf),NULL);
+}
+
+/* This function is called in beforeSleep() in order to unblock clients
+ * that are waiting in blocking operations with a timeout set. */
+void handleBlockedClientsTimeout(void) {
+    if (raxSize(server.clients_timeout_table) == 0) return;
+    uint64_t now = mstime();
+    raxIterator ri;
+    raxStart(&ri,server.clients_timeout_table);
+    raxSeek(&ri,"^",NULL,0);
+
+    while(raxNext(&ri)) {
+        uint64_t timeout;
+        client *c;
+        decodeTimeoutKey(ri.key,&timeout,&c);
+        if (timeout >= now) break; /* All the timeouts are in the future. */
+        c->flags &= ~CLIENT_IN_TO_TABLE;
+        checkBlockedClientTimeout(c,now);
+        raxRemove(server.clients_timeout_table,ri.key,ri.key_len,NULL);
+        raxSeek(&ri,"^",NULL,0);
+    }
+    raxStop(&ri);
+}
+
+/* Get a timeout value from an object and store it into 'timeout'.
+ * The final timeout is always stored as milliseconds as a time where the
+ * timeout will expire, however the parsing is performed according to
+ * the 'unit' that can be seconds or milliseconds.
+ *
+ * Note that if the timeout is zero (usually from the point of view of
+ * commands API this means no timeout) the value stored into 'timeout'
+ * is zero. */
+int getTimeoutFromObjectOrReply(client *c, robj *object, mstime_t *timeout, int unit) {
+    long long tval;
+    long double ftval;
+    mstime_t now = commandTimeSnapshot();
+
+    if (unit == UNIT_SECONDS) {
+        if (getLongDoubleFromObjectOrReply(c,object,&ftval,
+            "timeout is not a float or out of range") != C_OK)
+            return C_ERR;
+
+        ftval *= 1000.0;  /* seconds => millisec */
+        if (ftval > LLONG_MAX) {
+            addReplyError(c, "timeout is out of range");
+            return C_ERR;
+        }
+        tval = (long long) ceill(ftval);
+    } else {
+        if (getLongLongFromObjectOrReply(c,object,&tval,
+            "timeout is not an integer or out of range") != C_OK)
+            return C_ERR;
+    }
+
+    if (tval < 0) {
+        addReplyError(c,"timeout is negative");
+        return C_ERR;
+    }
+
+    if (tval > 0) {
+        if  (tval > LLONG_MAX - now) {
+            addReplyError(c,"timeout is out of range"); /* 'tval+now' would overflow */
+            return C_ERR;
+        }
+        tval += now;
+    }
+    *timeout = tval;
+
+    return C_OK;
+}