Add detecting of libhiredis for communicating with kvstorage.

Add internal hiredis if it is not found in system.

1 files changed, 552 insertions, 0 deletions

diff --git a/contrib/hiredis/async.c b/contrib/hiredis/async.c
new file mode 100644
index 000000000..cbbfb6d63
--- /dev/null
+++ b/contrib/hiredis/async.c
@@ -0,0 +1,552 @@
+/*
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2011, Pieter Noordhuis <pcnoordhuis 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 "fmacros.h"
+#include <string.h>
+#include <strings.h>
+#include <assert.h>
+#include <ctype.h>
+#include "async.h"
+#include "dict.c"
+#include "sds.h"
+
+/* Forward declaration of function in hiredis.c */
+void __redisAppendCommand(redisContext *c, char *cmd, size_t len);
+
+/* Functions managing dictionary of callbacks for pub/sub. */
+static unsigned int callbackHash(const void *key) {
+    return dictGenHashFunction((unsigned char*)key,sdslen((char*)key));
+}
+
+static void *callbackValDup(void *privdata, const void *src) {
+    ((void) privdata);
+    redisCallback *dup = malloc(sizeof(*dup));
+    memcpy(dup,src,sizeof(*dup));
+    return dup;
+}
+
+static int callbackKeyCompare(void *privdata, const void *key1, const void *key2) {
+    int l1, l2;
+    ((void) privdata);
+
+    l1 = sdslen((sds)key1);
+    l2 = sdslen((sds)key2);
+    if (l1 != l2) return 0;
+    return memcmp(key1,key2,l1) == 0;
+}
+
+static void callbackKeyDestructor(void *privdata, void *key) {
+    ((void) privdata);
+    sdsfree((sds)key);
+}
+
+static void callbackValDestructor(void *privdata, void *val) {
+    ((void) privdata);
+    free(val);
+}
+
+static dictType callbackDict = {
+    callbackHash,
+    NULL,
+    callbackValDup,
+    callbackKeyCompare,
+    callbackKeyDestructor,
+    callbackValDestructor
+};
+
+static redisAsyncContext *redisAsyncInitialize(redisContext *c) {
+    redisAsyncContext *ac = realloc(c,sizeof(redisAsyncContext));
+    c = &(ac->c);
+
+    /* The regular connect functions will always set the flag REDIS_CONNECTED.
+     * For the async API, we want to wait until the first write event is
+     * received up before setting this flag, so reset it here. */
+    c->flags &= ~REDIS_CONNECTED;
+
+    ac->err = 0;
+    ac->errstr = NULL;
+    ac->data = NULL;
+
+    ac->ev.data = NULL;
+    ac->ev.addRead = NULL;
+    ac->ev.delRead = NULL;
+    ac->ev.addWrite = NULL;
+    ac->ev.delWrite = NULL;
+    ac->ev.cleanup = NULL;
+
+    ac->onConnect = NULL;
+    ac->onDisconnect = NULL;
+
+    ac->replies.head = NULL;
+    ac->replies.tail = NULL;
+    ac->sub.invalid.head = NULL;
+    ac->sub.invalid.tail = NULL;
+    ac->sub.channels = dictCreate(&callbackDict,NULL);
+    ac->sub.patterns = dictCreate(&callbackDict,NULL);
+    return ac;
+}
+
+/* We want the error field to be accessible directly instead of requiring
+ * an indirection to the redisContext struct. */
+static void __redisAsyncCopyError(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    ac->err = c->err;
+    ac->errstr = c->errstr;
+}
+
+redisAsyncContext *redisAsyncConnect(const char *ip, int port) {
+    redisContext *c = redisConnectNonBlock(ip,port);
+    redisAsyncContext *ac = redisAsyncInitialize(c);
+    __redisAsyncCopyError(ac);
+    return ac;
+}
+
+redisAsyncContext *redisAsyncConnectUnix(const char *path) {
+    redisContext *c = redisConnectUnixNonBlock(path);
+    redisAsyncContext *ac = redisAsyncInitialize(c);
+    __redisAsyncCopyError(ac);
+    return ac;
+}
+
+int redisAsyncSetConnectCallback(redisAsyncContext *ac, redisConnectCallback *fn) {
+    if (ac->onConnect == NULL) {
+        ac->onConnect = fn;
+
+        /* The common way to detect an established connection is to wait for
+         * the first write event to be fired. This assumes the related event
+         * library functions are already set. */
+        if (ac->ev.addWrite) ac->ev.addWrite(ac->ev.data);
+        return REDIS_OK;
+    }
+    return REDIS_ERR;
+}
+
+int redisAsyncSetDisconnectCallback(redisAsyncContext *ac, redisDisconnectCallback *fn) {
+    if (ac->onDisconnect == NULL) {
+        ac->onDisconnect = fn;
+        return REDIS_OK;
+    }
+    return REDIS_ERR;
+}
+
+/* Helper functions to push/shift callbacks */
+static int __redisPushCallback(redisCallbackList *list, redisCallback *source) {
+    redisCallback *cb;
+
+    /* Copy callback from stack to heap */
+    cb = malloc(sizeof(*cb));
+    if (source != NULL) {
+        memcpy(cb,source,sizeof(*cb));
+        cb->next = NULL;
+    }
+
+    /* Store callback in list */
+    if (list->head == NULL)
+        list->head = cb;
+    if (list->tail != NULL)
+        list->tail->next = cb;
+    list->tail = cb;
+    return REDIS_OK;
+}
+
+static int __redisShiftCallback(redisCallbackList *list, redisCallback *target) {
+    redisCallback *cb = list->head;
+    if (cb != NULL) {
+        list->head = cb->next;
+        if (cb == list->tail)
+            list->tail = NULL;
+
+        /* Copy callback from heap to stack */
+        if (target != NULL)
+            memcpy(target,cb,sizeof(*cb));
+        free(cb);
+        return REDIS_OK;
+    }
+    return REDIS_ERR;
+}
+
+static void __redisRunCallback(redisAsyncContext *ac, redisCallback *cb, redisReply *reply) {
+    redisContext *c = &(ac->c);
+    if (cb->fn != NULL) {
+        c->flags |= REDIS_IN_CALLBACK;
+        cb->fn(ac,reply,cb->privdata);
+        c->flags &= ~REDIS_IN_CALLBACK;
+    }
+}
+
+/* Helper function to free the context. */
+static void __redisAsyncFree(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    redisCallback cb;
+    dictIterator *it;
+    dictEntry *de;
+
+    /* Execute pending callbacks with NULL reply. */
+    while (__redisShiftCallback(&ac->replies,&cb) == REDIS_OK)
+        __redisRunCallback(ac,&cb,NULL);
+
+    /* Execute callbacks for invalid commands */
+    while (__redisShiftCallback(&ac->sub.invalid,&cb) == REDIS_OK)
+        __redisRunCallback(ac,&cb,NULL);
+
+    /* Run subscription callbacks callbacks with NULL reply */
+    it = dictGetIterator(ac->sub.channels);
+    while ((de = dictNext(it)) != NULL)
+        __redisRunCallback(ac,dictGetEntryVal(de),NULL);
+    dictReleaseIterator(it);
+    dictRelease(ac->sub.channels);
+
+    it = dictGetIterator(ac->sub.patterns);
+    while ((de = dictNext(it)) != NULL)
+        __redisRunCallback(ac,dictGetEntryVal(de),NULL);
+    dictReleaseIterator(it);
+    dictRelease(ac->sub.patterns);
+
+    /* Signal event lib to clean up */
+    if (ac->ev.cleanup) ac->ev.cleanup(ac->ev.data);
+
+    /* Execute disconnect callback. When redisAsyncFree() initiated destroying
+     * this context, the status will always be REDIS_OK. */
+    if (ac->onDisconnect && (c->flags & REDIS_CONNECTED)) {
+        if (c->flags & REDIS_FREEING) {
+            ac->onDisconnect(ac,REDIS_OK);
+        } else {
+            ac->onDisconnect(ac,(ac->err == 0) ? REDIS_OK : REDIS_ERR);
+        }
+    }
+
+    /* Cleanup self */
+    redisFree(c);
+}
+
+/* Free the async context. When this function is called from a callback,
+ * control needs to be returned to redisProcessCallbacks() before actual
+ * free'ing. To do so, a flag is set on the context which is picked up by
+ * redisProcessCallbacks(). Otherwise, the context is immediately free'd. */
+void redisAsyncFree(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    c->flags |= REDIS_FREEING;
+    if (!(c->flags & REDIS_IN_CALLBACK))
+        __redisAsyncFree(ac);
+}
+
+/* Helper function to make the disconnect happen and clean up. */
+static void __redisAsyncDisconnect(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+
+    /* Make sure error is accessible if there is any */
+    __redisAsyncCopyError(ac);
+
+    if (ac->err == 0) {
+        /* For clean disconnects, there should be no pending callbacks. */
+        assert(__redisShiftCallback(&ac->replies,NULL) == REDIS_ERR);
+    } else {
+        /* Disconnection is caused by an error, make sure that pending
+         * callbacks cannot call new commands. */
+        c->flags |= REDIS_DISCONNECTING;
+    }
+
+    /* For non-clean disconnects, __redisAsyncFree() will execute pending
+     * callbacks with a NULL-reply. */
+    __redisAsyncFree(ac);
+}
+
+/* Tries to do a clean disconnect from Redis, meaning it stops new commands
+ * from being issued, but tries to flush the output buffer and execute
+ * callbacks for all remaining replies. When this function is called from a
+ * callback, there might be more replies and we can safely defer disconnecting
+ * to redisProcessCallbacks(). Otherwise, we can only disconnect immediately
+ * when there are no pending callbacks. */
+void redisAsyncDisconnect(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    c->flags |= REDIS_DISCONNECTING;
+    if (!(c->flags & REDIS_IN_CALLBACK) && ac->replies.head == NULL)
+        __redisAsyncDisconnect(ac);
+}
+
+static int __redisGetSubscribeCallback(redisAsyncContext *ac, redisReply *reply, redisCallback *dstcb) {
+    redisContext *c = &(ac->c);
+    dict *callbacks;
+    dictEntry *de;
+    int pvariant;
+    char *stype;
+    sds sname;
+
+    /* Custom reply functions are not supported for pub/sub. This will fail
+     * very hard when they are used... */
+    if (reply->type == REDIS_REPLY_ARRAY) {
+        assert(reply->elements >= 2);
+        assert(reply->element[0]->type == REDIS_REPLY_STRING);
+        stype = reply->element[0]->str;
+        pvariant = (tolower(stype[0]) == 'p') ? 1 : 0;
+
+        if (pvariant)
+            callbacks = ac->sub.patterns;
+        else
+            callbacks = ac->sub.channels;
+
+        /* Locate the right callback */
+        assert(reply->element[1]->type == REDIS_REPLY_STRING);
+        sname = sdsnewlen(reply->element[1]->str,reply->element[1]->len);
+        de = dictFind(callbacks,sname);
+        if (de != NULL) {
+            memcpy(dstcb,dictGetEntryVal(de),sizeof(*dstcb));
+
+            /* If this is an unsubscribe message, remove it. */
+            if (strcasecmp(stype+pvariant,"unsubscribe") == 0) {
+                dictDelete(callbacks,sname);
+
+                /* If this was the last unsubscribe message, revert to
+                 * non-subscribe mode. */
+                assert(reply->element[2]->type == REDIS_REPLY_INTEGER);
+                if (reply->element[2]->integer == 0)
+                    c->flags &= ~REDIS_SUBSCRIBED;
+            }
+        }
+        sdsfree(sname);
+    } else {
+        /* Shift callback for invalid commands. */
+        __redisShiftCallback(&ac->sub.invalid,dstcb);
+    }
+    return REDIS_OK;
+}
+
+void redisProcessCallbacks(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    redisCallback cb;
+    void *reply = NULL;
+    int status;
+
+    while((status = redisGetReply(c,&reply)) == REDIS_OK) {
+        if (reply == NULL) {
+            /* When the connection is being disconnected and there are
+             * no more replies, this is the cue to really disconnect. */
+            if (c->flags & REDIS_DISCONNECTING && sdslen(c->obuf) == 0) {
+                __redisAsyncDisconnect(ac);
+                return;
+            }
+
+            /* When the connection is not being disconnected, simply stop
+             * trying to get replies and wait for the next loop tick. */
+            break;
+        }
+
+        /* Even if the context is subscribed, pending regular callbacks will
+         * get a reply before pub/sub messages arrive. */
+        if (__redisShiftCallback(&ac->replies,&cb) != REDIS_OK) {
+            /* A spontaneous reply in a not-subscribed context can only be the
+             * error reply that is sent when a new connection exceeds the
+             * maximum number of allowed connections on the server side. This
+             * is seen as an error instead of a regular reply because the
+             * server closes the connection after sending it. To prevent the
+             * error from being overwritten by an EOF error the connection is
+             * closed here. See issue #43. */
+            if ( !(c->flags & REDIS_SUBSCRIBED) && ((redisReply*)reply)->type == REDIS_REPLY_ERROR ) {
+                c->err = REDIS_ERR_OTHER;
+                snprintf(c->errstr,sizeof(c->errstr),"%s",((redisReply*)reply)->str);
+                __redisAsyncDisconnect(ac);
+                return;
+            }
+            /* No more regular callbacks and no errors, the context *must* be subscribed. */
+            assert(c->flags & REDIS_SUBSCRIBED);
+            __redisGetSubscribeCallback(ac,reply,&cb);
+        }
+
+        if (cb.fn != NULL) {
+            __redisRunCallback(ac,&cb,reply);
+            c->reader->fn->freeObject(reply);
+
+            /* Proceed with free'ing when redisAsyncFree() was called. */
+            if (c->flags & REDIS_FREEING) {
+                __redisAsyncFree(ac);
+                return;
+            }
+        } else {
+            /* No callback for this reply. This can either be a NULL callback,
+             * or there were no callbacks to begin with. Either way, don't
+             * abort with an error, but simply ignore it because the client
+             * doesn't know what the server will spit out over the wire. */
+            c->reader->fn->freeObject(reply);
+        }
+    }
+
+    /* Disconnect when there was an error reading the reply */
+    if (status != REDIS_OK)
+        __redisAsyncDisconnect(ac);
+}
+
+/* This function should be called when the socket is readable.
+ * It processes all replies that can be read and executes their callbacks.
+ */
+void redisAsyncHandleRead(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+
+    if (redisBufferRead(c) == REDIS_ERR) {
+        __redisAsyncDisconnect(ac);
+    } else {
+        /* Always re-schedule reads */
+        if (ac->ev.addRead) ac->ev.addRead(ac->ev.data);
+        redisProcessCallbacks(ac);
+    }
+}
+
+void redisAsyncHandleWrite(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    int done = 0;
+
+    if (redisBufferWrite(c,&done) == REDIS_ERR) {
+        __redisAsyncDisconnect(ac);
+    } else {
+        /* Continue writing when not done, stop writing otherwise */
+        if (!done) {
+            if (ac->ev.addWrite) ac->ev.addWrite(ac->ev.data);
+        } else {
+            if (ac->ev.delWrite) ac->ev.delWrite(ac->ev.data);
+        }
+
+        /* Always schedule reads after writes */
+        if (ac->ev.addRead) ac->ev.addRead(ac->ev.data);
+
+        /* Fire onConnect when this is the first write event. */
+        if (!(c->flags & REDIS_CONNECTED)) {
+            c->flags |= REDIS_CONNECTED;
+            if (ac->onConnect) ac->onConnect(ac);
+        }
+    }
+}
+
+/* Sets a pointer to the first argument and its length starting at p. Returns
+ * the number of bytes to skip to get to the following argument. */
+static char *nextArgument(char *start, char **str, size_t *len) {
+    char *p = start;
+    if (p[0] != '$') {
+        p = strchr(p,'$');
+        if (p == NULL) return NULL;
+    }
+
+    *len = (int)strtol(p+1,NULL,10);
+    p = strchr(p,'\r');
+    assert(p);
+    *str = p+2;
+    return p+2+(*len)+2;
+}
+
+/* Helper function for the redisAsyncCommand* family of functions. Writes a
+ * formatted command to the output buffer and registers the provided callback
+ * function with the context. */
+static int __redisAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, char *cmd, size_t len) {
+    redisContext *c = &(ac->c);
+    redisCallback cb;
+    int pvariant, hasnext;
+    char *cstr, *astr;
+    size_t clen, alen;
+    char *p;
+    sds sname;
+
+    /* Don't accept new commands when the connection is about to be closed. */
+    if (c->flags & (REDIS_DISCONNECTING | REDIS_FREEING)) return REDIS_ERR;
+
+    /* Setup callback */
+    cb.fn = fn;
+    cb.privdata = privdata;
+
+    /* Find out which command will be appended. */
+    p = nextArgument(cmd,&cstr,&clen);
+    assert(p != NULL);
+    hasnext = (p[0] == '$');
+    pvariant = (tolower(cstr[0]) == 'p') ? 1 : 0;
+    cstr += pvariant;
+    clen -= pvariant;
+
+    if (hasnext && strncasecmp(cstr,"subscribe\r\n",11) == 0) {
+        c->flags |= REDIS_SUBSCRIBED;
+
+        /* Add every channel/pattern to the list of subscription callbacks. */
+        while ((p = nextArgument(p,&astr,&alen)) != NULL) {
+            sname = sdsnewlen(astr,alen);
+            if (pvariant)
+                dictReplace(ac->sub.patterns,sname,&cb);
+            else
+                dictReplace(ac->sub.channels,sname,&cb);
+        }
+    } else if (strncasecmp(cstr,"unsubscribe\r\n",13) == 0) {
+        /* It is only useful to call (P)UNSUBSCRIBE when the context is
+         * subscribed to one or more channels or patterns. */
+        if (!(c->flags & REDIS_SUBSCRIBED)) return REDIS_ERR;
+
+        /* (P)UNSUBSCRIBE does not have its own response: every channel or
+         * pattern that is unsubscribed will receive a message. This means we
+         * should not append a callback function for this command. */
+    } else {
+        if (c->flags & REDIS_SUBSCRIBED)
+            /* This will likely result in an error reply, but it needs to be
+             * received and passed to the callback. */
+            __redisPushCallback(&ac->sub.invalid,&cb);
+        else
+            __redisPushCallback(&ac->replies,&cb);
+    }
+
+    __redisAppendCommand(c,cmd,len);
+
+    /* Always schedule a write when the write buffer is non-empty */
+    if (ac->ev.addWrite) ac->ev.addWrite(ac->ev.data);
+
+    return REDIS_OK;
+}
+
+int redisvAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *format, va_list ap) {
+    char *cmd;
+    int len;
+    int status;
+    len = redisvFormatCommand(&cmd,format,ap);
+    status = __redisAsyncCommand(ac,fn,privdata,cmd,len);
+    free(cmd);
+    return status;
+}
+
+int redisAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *format, ...) {
+    va_list ap;
+    int status;
+    va_start(ap,format);
+    status = redisvAsyncCommand(ac,fn,privdata,format,ap);
+    va_end(ap);
+    return status;
+}
+
+int redisAsyncCommandArgv(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, int argc, const char **argv, const size_t *argvlen) {
+    char *cmd;
+    int len;
+    int status;
+    len = redisFormatCommandArgv(&cmd,argc,argv,argvlen);
+    status = __redisAsyncCommand(ac,fn,privdata,cmd,len);
+    free(cmd);
+    return status;
+}