Merge pull request #234 from mattsta/next-version

Next version of hiredis

15 files changed, 747 insertions, 200 deletions

diff --git a/Makefile b/Makefile
index c8632b4..969115b 100644
--- a/Makefile
+++ b/Makefile
@@ -11,6 +11,18 @@ LIBNAME=libhiredis
 HIREDIS_MAJOR=0
 HIREDIS_MINOR=10
 
+# redis-server configuration used for testing
+REDIS_PORT=56379
+REDIS_SERVER=redis-server
+define REDIS_TEST_CONFIG
+	daemonize yes
+	pidfile /tmp/hiredis-test-redis.pid
+	port $(REDIS_PORT)
+	bind 127.0.0.1
+	unixsocket /tmp/hiredis-test-redis.sock
+endef
+export REDIS_TEST_CONFIG
+
 # Fallback to gcc when $CC is not in $PATH.
 CC:=$(shell sh -c 'type $(CC) >/dev/null 2>/dev/null && echo $(CC) || echo gcc')
 OPTIMIZATION?=-O3
@@ -97,14 +109,8 @@ test: hiredis-test
 	./hiredis-test
 
 check: hiredis-test
-	echo \
-		"daemonize yes\n" \
-		"pidfile /tmp/hiredis-test-redis.pid\n" \
-		"port 56379\n" \
-		"bind 127.0.0.1\n" \
-		"unixsocket /tmp/hiredis-test-redis.sock" \
-			| redis-server -
-	./hiredis-test -h 127.0.0.1 -p 56379 -s /tmp/hiredis-test-redis.sock || \
+	@echo "$$REDIS_TEST_CONFIG" | $(REDIS_SERVER) -
+	./hiredis-test -h 127.0.0.1 -p $(REDIS_PORT) -s /tmp/hiredis-test-redis.sock || \
 			( kill `cat /tmp/hiredis-test-redis.pid` && false )
 	kill `cat /tmp/hiredis-test-redis.pid`
 
diff --git a/adapters/ae.h b/adapters/ae.h
index 65235f8..5c551c2 100644
--- a/adapters/ae.h
+++ b/adapters/ae.h
@@ -1,3 +1,33 @@
+/*
+ * 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.
+ */
+
 #ifndef __HIREDIS_AE_H__
 #define __HIREDIS_AE_H__
 #include <sys/types.h>
diff --git a/adapters/libev.h b/adapters/libev.h
index 534d743..2bf8d52 100644
--- a/adapters/libev.h
+++ b/adapters/libev.h
@@ -1,3 +1,33 @@
+/*
+ * 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.
+ */
+
 #ifndef __HIREDIS_LIBEV_H__
 #define __HIREDIS_LIBEV_H__
 #include <stdlib.h>
diff --git a/adapters/libevent.h b/adapters/libevent.h
index 4055ec0..1c2b271 100644
--- a/adapters/libevent.h
+++ b/adapters/libevent.h
@@ -1,3 +1,33 @@
+/*
+ * 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.
+ */
+
 #ifndef __HIREDIS_LIBEVENT_H__
 #define __HIREDIS_LIBEVENT_H__
 #include <event.h>
diff --git a/adapters/libuv.h b/adapters/libuv.h
index e61d5ca..a1967f4 100644
--- a/adapters/libuv.h
+++ b/adapters/libuv.h
@@ -3,7 +3,7 @@
 #include <uv.h>
 #include "../hiredis.h"
 #include "../async.h"
-
+#include <string.h>
 
 typedef struct redisLibuvEvents {
   redisAsyncContext* context;
@@ -11,6 +11,7 @@ typedef struct redisLibuvEvents {
   int                events;
 } redisLibuvEvents;
 
+int redisLibuvAttach(redisAsyncContext*, uv_loop_t*);
 
 static void redisLibuvPoll(uv_poll_t* handle, int status, int events) {
   redisLibuvEvents* p = (redisLibuvEvents*)handle->data;
@@ -86,7 +87,7 @@ static void redisLibuvCleanup(void *privdata) {
 }
 
 
-int redisLibuvAttach(redisAsyncContext* ac, uv_loop_t* loop) {
+static int redisLibuvAttach(redisAsyncContext* ac, uv_loop_t* loop) {
   redisContext *c = &(ac->c);
 
   if (ac->ev.data != NULL) {
@@ -99,7 +100,7 @@ int redisLibuvAttach(redisAsyncContext* ac, uv_loop_t* loop) {
   ac->ev.delWrite = redisLibuvDelWrite;
   ac->ev.cleanup  = redisLibuvCleanup;
 
-  redisLibuvEvents* p = malloc(sizeof(*p));
+  redisLibuvEvents* p = (redisLibuvEvents*)malloc(sizeof(*p));
 
   if (!p) {
     return REDIS_ERR;
diff --git a/async.c b/async.c
index 923a329..7fd17f2 100644
--- a/async.c
+++ b/async.c
@@ -165,6 +165,14 @@ redisAsyncContext *redisAsyncConnect(const char *ip, int port) {
     return ac;
 }
 
+redisAsyncContext *redisAsyncConnectBind(const char *ip, int port,
+                                         char *source_addr) {
+    redisContext *c = redisConnectBindNonBlock(ip,port,source_addr);
+    redisAsyncContext *ac = redisAsyncInitialize(c);
+    __redisAsyncCopyError(ac);
+    return ac;
+}
+
 redisAsyncContext *redisAsyncConnectUnix(const char *path) {
     redisContext *c;
     redisAsyncContext *ac;
@@ -391,7 +399,7 @@ static int __redisGetSubscribeCallback(redisAsyncContext *ac, redisReply *reply,
 
 void redisProcessCallbacks(redisAsyncContext *ac) {
     redisContext *c = &(ac->c);
-    redisCallback cb;
+    redisCallback cb = {NULL, NULL, NULL};
     void *reply = NULL;
     int status;
 
@@ -473,7 +481,7 @@ void redisProcessCallbacks(redisAsyncContext *ac) {
 static int __redisAsyncHandleConnect(redisAsyncContext *ac) {
     redisContext *c = &(ac->c);
 
-    if (redisCheckSocketError(c,c->fd) == REDIS_ERR) {
+    if (redisCheckSocketError(c) == REDIS_ERR) {
         /* Try again later when connect(2) is still in progress. */
         if (errno == EINPROGRESS)
             return REDIS_OK;
diff --git a/async.h b/async.h
index 268274e..1df2ff0 100644
--- a/async.h
+++ b/async.h
@@ -102,6 +102,7 @@ typedef struct redisAsyncContext {
 
 /* Functions that proxy to hiredis */
 redisAsyncContext *redisAsyncConnect(const char *ip, int port);
+redisAsyncContext *redisAsyncConnectBind(const char *ip, int port,char *source);
 redisAsyncContext *redisAsyncConnectUnix(const char *path);
 int redisAsyncSetConnectCallback(redisAsyncContext *ac, redisConnectCallback *fn);
 int redisAsyncSetDisconnectCallback(redisAsyncContext *ac, redisDisconnectCallback *fn);
diff --git a/fmacros.h b/fmacros.h
index 799c12c..9e5fec0 100644
--- a/fmacros.h
+++ b/fmacros.h
@@ -7,7 +7,7 @@
 
 #if defined(__sun__)
 #define _POSIX_C_SOURCE 200112L
-#elif defined(__linux__)
+#elif defined(__linux__) || defined(__OpenBSD__) || defined(__NetBSD__)
 #define _XOPEN_SOURCE 600
 #else
 #define _XOPEN_SOURCE
diff --git a/hiredis.c b/hiredis.c
index 9b74b5b..4054de6 100644
--- a/hiredis.c
+++ b/hiredis.c
@@ -650,7 +650,7 @@ int redisReaderGetReply(redisReader *r, void **reply) {
     /* Discard part of the buffer when we've consumed at least 1k, to avoid
      * doing unnecessary calls to memmove() in sds.c. */
     if (r->pos >= 1024) {
-        r->buf = sdsrange(r->buf,r->pos,-1);
+        sdsrange(r->buf,r->pos,-1);
         r->pos = 0;
         r->len = sdslen(r->buf);
     }
@@ -1010,6 +1010,13 @@ void redisFree(redisContext *c) {
     free(c);
 }
 
+int redisFreeKeepFd(redisContext *c) {
+	int fd = c->fd;
+	c->fd = -1;
+	redisFree(c);
+	return fd;
+}
+
 /* Connect to a Redis instance. On error the field error in the returned
  * context will be set to the return value of the error function.
  * When no set of reply functions is given, the default set will be used. */
@@ -1049,6 +1056,14 @@ redisContext *redisConnectNonBlock(const char *ip, int port) {
     return c;
 }
 
+redisContext *redisConnectBindNonBlock(const char *ip, int port,
+                                   char *source_addr) {
+    redisContext *c = redisContextInit();
+    c->flags &= ~REDIS_BLOCK;
+    redisContextConnectBindTcp(c,ip,port,NULL,source_addr);
+    return c;
+}
+
 redisContext *redisConnectUnix(const char *path) {
     redisContext *c;
 
@@ -1085,6 +1100,18 @@ redisContext *redisConnectUnixNonBlock(const char *path) {
     return c;
 }
 
+redisContext *redisConnectFd(int fd) {
+    redisContext *c;
+
+    c = redisContextInit();
+    if (c == NULL)
+        return NULL;
+
+    c->fd = fd;
+    c->flags |= REDIS_BLOCK | REDIS_CONNECTED;
+    return c;
+}
+
 /* Set read/write timeout on a blocking socket. */
 int redisSetTimeout(redisContext *c, const struct timeval tv) {
     if (c->flags & REDIS_BLOCK)
@@ -1162,7 +1189,7 @@ int redisBufferWrite(redisContext *c, int *done) {
                 sdsfree(c->obuf);
                 c->obuf = sdsempty();
             } else {
-                c->obuf = sdsrange(c->obuf,nwritten,-1);
+                sdsrange(c->obuf,nwritten,-1);
             }
         }
     }
@@ -1230,6 +1257,15 @@ int __redisAppendCommand(redisContext *c, char *cmd, size_t len) {
     return REDIS_OK;
 }
 
+int redisAppendFormattedCommand(redisContext *c, char *format, size_t len) {
+
+    if (__redisAppendCommand(c, format, len) != REDIS_OK) {
+        return REDIS_ERR;
+    }
+
+    return REDIS_OK;
+}
+
 int redisvAppendCommand(redisContext *c, const char *format, va_list ap) {
     char *cmd;
     int len;
diff --git a/hiredis.h b/hiredis.h
index c65098b..05bfc47 100644
--- a/hiredis.h
+++ b/hiredis.h
@@ -175,12 +175,15 @@ typedef struct redisContext {
 redisContext *redisConnect(const char *ip, int port);
 redisContext *redisConnectWithTimeout(const char *ip, int port, const struct timeval tv);
 redisContext *redisConnectNonBlock(const char *ip, int port);
+redisContext *redisConnectBindNonBlock(const char *ip, int port, char *source);
 redisContext *redisConnectUnix(const char *path);
 redisContext *redisConnectUnixWithTimeout(const char *path, const struct timeval tv);
 redisContext *redisConnectUnixNonBlock(const char *path);
+redisContext *redisConnectFd(int fd);
 int redisSetTimeout(redisContext *c, const struct timeval tv);
 int redisEnableKeepAlive(redisContext *c);
 void redisFree(redisContext *c);
+int redisFreeKeepFd(redisContext *c);
 int redisBufferRead(redisContext *c);
 int redisBufferWrite(redisContext *c, int *done);
 
@@ -191,6 +194,10 @@ int redisBufferWrite(redisContext *c, int *done);
 int redisGetReply(redisContext *c, void **reply);
 int redisGetReplyFromReader(redisContext *c, void **reply);
 
+/* Write a formatted command to the output buffer. Use these functions in blocking mode
+ * to get a pipeline of commands. */
+int redisAppendFormattedCommand(redisContext *c, char *format, size_t len);
+
 /* Write a command to the output buffer. Use these functions in blocking mode
  * to get a pipeline of commands. */
 int redisvAppendCommand(redisContext *c, const char *format, va_list ap);
diff --git a/net.c b/net.c
index 603699c..7c787df 100644
--- a/net.c
+++ b/net.c
@@ -54,6 +54,13 @@
 /* Defined in hiredis.c */
 void __redisSetError(redisContext *c, int type, const char *str);
 
+static void redisContextCloseFd(redisContext *c) {
+    if (c && c->fd > 0) {
+        close(c->fd);
+        c->fd = -1;
+    }
+}
+
 static void __redisSetErrorFromErrno(redisContext *c, int type, const char *prefix) {
     char buf[128] = { 0 };
     size_t len = 0;
@@ -64,11 +71,11 @@ static void __redisSetErrorFromErrno(redisContext *c, int type, const char *pref
     __redisSetError(c,type,buf);
 }
 
-static int redisSetReuseAddr(redisContext *c, int fd) {
+static int redisSetReuseAddr(redisContext *c) {
     int on = 1;
-    if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) {
+    if (setsockopt(c->fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) {
         __redisSetErrorFromErrno(c,REDIS_ERR_IO,NULL);
-        close(fd);
+        redisContextCloseFd(c);
         return REDIS_ERR;
     }
     return REDIS_OK;
@@ -80,23 +87,24 @@ static int redisCreateSocket(redisContext *c, int type) {
         __redisSetErrorFromErrno(c,REDIS_ERR_IO,NULL);
         return REDIS_ERR;
     }
+    c->fd = s;
     if (type == AF_INET) {
-        if (redisSetReuseAddr(c,s) == REDIS_ERR) {
+        if (redisSetReuseAddr(c) == REDIS_ERR) {
             return REDIS_ERR;
         }
     }
-    return s;
+    return REDIS_OK;
 }
 
-static int redisSetBlocking(redisContext *c, int fd, int blocking) {
+static int redisSetBlocking(redisContext *c, int blocking) {
     int flags;
 
     /* Set the socket nonblocking.
      * Note that fcntl(2) for F_GETFL and F_SETFL can't be
      * interrupted by a signal. */
-    if ((flags = fcntl(fd, F_GETFL)) == -1) {
+    if ((flags = fcntl(c->fd, F_GETFL)) == -1) {
         __redisSetErrorFromErrno(c,REDIS_ERR_IO,"fcntl(F_GETFL)");
-        close(fd);
+        redisContextCloseFd(c);
         return REDIS_ERR;
     }
 
@@ -105,9 +113,9 @@ static int redisSetBlocking(redisContext *c, int fd, int blocking) {
     else
         flags |= O_NONBLOCK;
 
-    if (fcntl(fd, F_SETFL, flags) == -1) {
+    if (fcntl(c->fd, F_SETFL, flags) == -1) {
         __redisSetErrorFromErrno(c,REDIS_ERR_IO,"fcntl(F_SETFL)");
-        close(fd);
+        redisContextCloseFd(c);
         return REDIS_ERR;
     }
     return REDIS_OK;
@@ -122,13 +130,15 @@ int redisKeepAlive(redisContext *c, int interval) {
         return REDIS_ERR;
     }
 
-#ifdef _OSX
     val = interval;
+
+#ifdef _OSX
     if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPALIVE, &val, sizeof(val)) < 0) {
         __redisSetError(c,REDIS_ERR_OTHER,strerror(errno));
         return REDIS_ERR;
     }
 #else
+#ifndef __sun
     val = interval;
     if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPIDLE, &val, sizeof(val)) < 0) {
         __redisSetError(c,REDIS_ERR_OTHER,strerror(errno));
@@ -148,15 +158,16 @@ int redisKeepAlive(redisContext *c, int interval) {
         return REDIS_ERR;
     }
 #endif
+#endif
 
     return REDIS_OK;
 }
 
-static int redisSetTcpNoDelay(redisContext *c, int fd) {
+static int redisSetTcpNoDelay(redisContext *c) {
     int yes = 1;
-    if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &yes, sizeof(yes)) == -1) {
+    if (setsockopt(c->fd, IPPROTO_TCP, TCP_NODELAY, &yes, sizeof(yes)) == -1) {
         __redisSetErrorFromErrno(c,REDIS_ERR_IO,"setsockopt(TCP_NODELAY)");
-        close(fd);
+        redisContextCloseFd(c);
         return REDIS_ERR;
     }
     return REDIS_OK;
@@ -164,19 +175,19 @@ static int redisSetTcpNoDelay(redisContext *c, int fd) {
 
 #define __MAX_MSEC (((LONG_MAX) - 999) / 1000)
 
-static int redisContextWaitReady(redisContext *c, int fd, const struct timeval *timeout) {
+static int redisContextWaitReady(redisContext *c, const struct timeval *timeout) {
     struct pollfd   wfd[1];
     long msec;
 
     msec          = -1;
-    wfd[0].fd     = fd;
+    wfd[0].fd     = c->fd;
     wfd[0].events = POLLOUT;
 
     /* Only use timeout when not NULL. */
     if (timeout != NULL) {
         if (timeout->tv_usec > 1000000 || timeout->tv_sec > __MAX_MSEC) {
             __redisSetErrorFromErrno(c, REDIS_ERR_IO, NULL);
-            close(fd);
+            redisContextCloseFd(c);
             return REDIS_ERR;
         }
 
@@ -192,40 +203,38 @@ static int redisContextWaitReady(redisContext *c, int fd, const struct timeval *
 
         if ((res = poll(wfd, 1, msec)) == -1) {
             __redisSetErrorFromErrno(c, REDIS_ERR_IO, "poll(2)");
-            close(fd);
+            redisContextCloseFd(c);
             return REDIS_ERR;
         } else if (res == 0) {
             errno = ETIMEDOUT;
             __redisSetErrorFromErrno(c,REDIS_ERR_IO,NULL);
-            close(fd);
+            redisContextCloseFd(c);
             return REDIS_ERR;
         }
 
-        if (redisCheckSocketError(c, fd) != REDIS_OK)
+        if (redisCheckSocketError(c) != REDIS_OK)
             return REDIS_ERR;
 
         return REDIS_OK;
     }
 
     __redisSetErrorFromErrno(c,REDIS_ERR_IO,NULL);
-    close(fd);
+    redisContextCloseFd(c);
     return REDIS_ERR;
 }
 
-int redisCheckSocketError(redisContext *c, int fd) {
+int redisCheckSocketError(redisContext *c) {
     int err = 0;
     socklen_t errlen = sizeof(err);
 
-    if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errlen) == -1) {
+    if (getsockopt(c->fd, SOL_SOCKET, SO_ERROR, &err, &errlen) == -1) {
         __redisSetErrorFromErrno(c,REDIS_ERR_IO,"getsockopt(SO_ERROR)");
-        close(fd);
         return REDIS_ERR;
     }
 
     if (err) {
         errno = err;
         __redisSetErrorFromErrno(c,REDIS_ERR_IO,NULL);
-        close(fd);
         return REDIS_ERR;
     }
 
@@ -244,10 +253,12 @@ int redisContextSetTimeout(redisContext *c, const struct timeval tv) {
     return REDIS_OK;
 }
 
-int redisContextConnectTcp(redisContext *c, const char *addr, int port, const struct timeval *timeout) {
+static int _redisContextConnectTcp(redisContext *c, const char *addr, int port,
+                                   const struct timeval *timeout,
+                                   char *source_addr) {
     int s, rv;
     char _port[6];  /* strlen("65535"); */
-    struct addrinfo hints, *servinfo, *p;
+    struct addrinfo hints, *servinfo, *bservinfo, *p, *b;
     int blocking = (c->flags & REDIS_BLOCK);
 
     snprintf(_port, 6, "%d", port);
@@ -271,25 +282,47 @@ int redisContextConnectTcp(redisContext *c, const char *addr, int port, const st
         if ((s = socket(p->ai_family,p->ai_socktype,p->ai_protocol)) == -1)
             continue;
 
-        if (redisSetBlocking(c,s,0) != REDIS_OK)
+        c->fd = s;
+        if (redisSetBlocking(c,0) != REDIS_OK)
             goto error;
+        if (source_addr) {
+            int bound = 0;
+            /* Using getaddrinfo saves us from self-determining IPv4 vs IPv6 */
+            if ((rv = getaddrinfo(source_addr, NULL, &hints, &bservinfo)) != 0) {
+                char buf[128];
+                snprintf(buf,sizeof(buf),"Can't get addr: %s",gai_strerror(rv));
+                __redisSetError(c,REDIS_ERR_OTHER,buf);
+                goto error;
+            }
+            for (b = bservinfo; b != NULL; b = b->ai_next) {
+                if (bind(s,b->ai_addr,b->ai_addrlen) != -1) {
+                    bound = 1;
+                    break;
+                }
+            }
+            if (!bound) {
+                char buf[128];
+                snprintf(buf,sizeof(buf),"Can't bind socket: %s",strerror(errno));
+                __redisSetError(c,REDIS_ERR_OTHER,buf);
+                goto error;
+            }
+        }
         if (connect(s,p->ai_addr,p->ai_addrlen) == -1) {
             if (errno == EHOSTUNREACH) {
-                close(s);
+                redisContextCloseFd(c);
                 continue;
             } else if (errno == EINPROGRESS && !blocking) {
                 /* This is ok. */
             } else {
-                if (redisContextWaitReady(c,s,timeout) != REDIS_OK)
+                if (redisContextWaitReady(c,timeout) != REDIS_OK)
                     goto error;
             }
         }
-        if (blocking && redisSetBlocking(c,s,1) != REDIS_OK)
+        if (blocking && redisSetBlocking(c,1) != REDIS_OK)
             goto error;
-        if (redisSetTcpNoDelay(c,s) != REDIS_OK)
+        if (redisSetTcpNoDelay(c) != REDIS_OK)
             goto error;
 
-        c->fd = s;
         c->flags |= REDIS_CONNECTED;
         rv = REDIS_OK;
         goto end;
@@ -308,32 +341,40 @@ end:
     return rv;  // Need to return REDIS_OK if alright
 }
 
+int redisContextConnectTcp(redisContext *c, const char *addr, int port,
+                           const struct timeval *timeout) {
+    return _redisContextConnectTcp(c, addr, port, timeout, NULL);
+}
+
+int redisContextConnectBindTcp(redisContext *c, const char *addr, int port,
+                               const struct timeval *timeout, char *source_addr) {
+    return _redisContextConnectTcp(c, addr, port, timeout, source_addr);
+}
+
 int redisContextConnectUnix(redisContext *c, const char *path, const struct timeval *timeout) {
-    int s;
     int blocking = (c->flags & REDIS_BLOCK);
     struct sockaddr_un sa;
 
-    if ((s = redisCreateSocket(c,AF_LOCAL)) < 0)
+    if (redisCreateSocket(c,AF_LOCAL) < 0)
         return REDIS_ERR;
-    if (redisSetBlocking(c,s,0) != REDIS_OK)
+    if (redisSetBlocking(c,0) != REDIS_OK)
         return REDIS_ERR;
 
     sa.sun_family = AF_LOCAL;
     strncpy(sa.sun_path,path,sizeof(sa.sun_path)-1);
-    if (connect(s, (struct sockaddr*)&sa, sizeof(sa)) == -1) {
+    if (connect(c->fd, (struct sockaddr*)&sa, sizeof(sa)) == -1) {
         if (errno == EINPROGRESS && !blocking) {
             /* This is ok. */
         } else {
-            if (redisContextWaitReady(c,s,timeout) != REDIS_OK)
+            if (redisContextWaitReady(c,timeout) != REDIS_OK)
                 return REDIS_ERR;
         }
     }
 
     /* Reset socket to be blocking after connect(2). */
-    if (blocking && redisSetBlocking(c,s,1) != REDIS_OK)
+    if (blocking && redisSetBlocking(c,1) != REDIS_OK)
         return REDIS_ERR;
 
-    c->fd = s;
     c->flags |= REDIS_CONNECTED;
     return REDIS_OK;
 }
diff --git a/net.h b/net.h
index 94b76f5..370a1ff 100644
--- a/net.h
+++ b/net.h
@@ -39,9 +39,11 @@
 #define AF_LOCAL AF_UNIX
 #endif
 
-int redisCheckSocketError(redisContext *c, int fd);
+int redisCheckSocketError(redisContext *c);
 int redisContextSetTimeout(redisContext *c, const struct timeval tv);
 int redisContextConnectTcp(redisContext *c, const char *addr, int port, const struct timeval *timeout);
+int redisContextConnectBindTcp(redisContext *c, const char *addr, int port,
+                               const struct timeval *timeout, char *source_addr);
 int redisContextConnectUnix(redisContext *c, const char *path, const struct timeval *timeout);
 int redisKeepAlive(redisContext *c, int interval);
 
diff --git a/sds.c b/sds.c
index 998564d..5306f1f 100644
--- a/sds.c
+++ b/sds.c
@@ -1,6 +1,6 @@
-/* SDSLib, A C dynamic strings library
+/* SDS (Simple Dynamic Strings), A C dynamic strings library.
  *
- * Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2006-2014, Salvatore Sanfilippo <antirez at gmail dot com>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -32,83 +32,188 @@
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
-#include "sds.h"
+#include <assert.h>
 
-#ifdef SDS_ABORT_ON_OOM
-static void sdsOomAbort(void) {
-    fprintf(stderr,"SDS: Out Of Memory (SDS_ABORT_ON_OOM defined)\n");
-    abort();
-}
-#endif
+#include "sds.h"
 
+/* Create a new sds string with the content specified by the 'init' pointer
+ * and 'initlen'.
+ * If NULL is used for 'init' the string is initialized with zero bytes.
+ *
+ * The string is always null-termined (all the sds strings are, always) so
+ * even if you create an sds string with:
+ *
+ * mystring = sdsnewlen("abc",3");
+ *
+ * You can print the string with printf() as there is an implicit \0 at the
+ * end of the string. However the string is binary safe and can contain
+ * \0 characters in the middle, as the length is stored in the sds header. */
 sds sdsnewlen(const void *init, size_t initlen) {
     struct sdshdr *sh;
 
-    sh = malloc(sizeof(struct sdshdr)+initlen+1);
-#ifdef SDS_ABORT_ON_OOM
-    if (sh == NULL) sdsOomAbort();
-#else
+    if (init) {
+        sh = malloc(sizeof *sh+initlen+1);
+    } else {
+        sh = calloc(sizeof *sh+initlen+1,1);
+    }
     if (sh == NULL) return NULL;
-#endif
     sh->len = initlen;
     sh->free = 0;
-    if (initlen) {
-        if (init) memcpy(sh->buf, init, initlen);
-        else memset(sh->buf,0,initlen);
-    }
+    if (initlen && init)
+        memcpy(sh->buf, init, initlen);
     sh->buf[initlen] = '\0';
     return (char*)sh->buf;
 }
 
+/* Create an empty (zero length) sds string. Even in this case the string
+ * always has an implicit null term. */
 sds sdsempty(void) {
     return sdsnewlen("",0);
 }
 
+/* Create a new sds string starting from a null termined C string. */
 sds sdsnew(const char *init) {
     size_t initlen = (init == NULL) ? 0 : strlen(init);
     return sdsnewlen(init, initlen);
 }
 
+/* Duplicate an sds string. */
 sds sdsdup(const sds s) {
     return sdsnewlen(s, sdslen(s));
 }
 
+/* Free an sds string. No operation is performed if 's' is NULL. */
 void sdsfree(sds s) {
     if (s == NULL) return;
     free(s-sizeof(struct sdshdr));
 }
 
+/* Set the sds string length to the length as obtained with strlen(), so
+ * considering as content only up to the first null term character.
+ *
+ * This function is useful when the sds string is hacked manually in some
+ * way, like in the following example:
+ *
+ * s = sdsnew("foobar");
+ * s[2] = '\0';
+ * sdsupdatelen(s);
+ * printf("%d\n", sdslen(s));
+ *
+ * The output will be "2", but if we comment out the call to sdsupdatelen()
+ * the output will be "6" as the string was modified but the logical length
+ * remains 6 bytes. */
 void sdsupdatelen(sds s) {
-    struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
+    struct sdshdr *sh = (void*) (s-sizeof *sh);;
     int reallen = strlen(s);
     sh->free += (sh->len-reallen);
     sh->len = reallen;
 }
 
-static sds sdsMakeRoomFor(sds s, size_t addlen) {
+/* Modify an sds string on-place to make it empty (zero length).
+ * However all the existing buffer is not discarded but set as free space
+ * so that next append operations will not require allocations up to the
+ * number of bytes previously available. */
+void sdsclear(sds s) {
+    struct sdshdr *sh = (void*) (s-sizeof *sh);;
+    sh->free += sh->len;
+    sh->len = 0;
+    sh->buf[0] = '\0';
+}
+
+/* Enlarge the free space at the end of the sds string so that the caller
+ * is sure that after calling this function can overwrite up to addlen
+ * bytes after the end of the string, plus one more byte for nul term.
+ * 
+ * Note: this does not change the *length* of the sds string as returned
+ * by sdslen(), but only the free buffer space we have. */
+sds sdsMakeRoomFor(sds s, size_t addlen) {
     struct sdshdr *sh, *newsh;
     size_t free = sdsavail(s);
     size_t len, newlen;
 
     if (free >= addlen) return s;
     len = sdslen(s);
-    sh = (void*) (s-(sizeof(struct sdshdr)));
-    newlen = (len+addlen)*2;
-    newsh = realloc(sh, sizeof(struct sdshdr)+newlen+1);
-#ifdef SDS_ABORT_ON_OOM
-    if (newsh == NULL) sdsOomAbort();
-#else
+    sh = (void*) (s-sizeof *sh);;
+    newlen = (len+addlen);
+    if (newlen < SDS_MAX_PREALLOC)
+        newlen *= 2;
+    else
+        newlen += SDS_MAX_PREALLOC;
+    newsh = realloc(sh, sizeof *newsh+newlen+1);
     if (newsh == NULL) return NULL;
-#endif
 
     newsh->free = newlen - len;
     return newsh->buf;
 }
 
+/* Reallocate the sds string so that it has no free space at the end. The
+ * contained string remains not altered, but next concatenation operations
+ * will require a reallocation.
+ *
+ * After the call, the passed sds string is no longer valid and all the
+ * references must be substituted with the new pointer returned by the call. */
+sds sdsRemoveFreeSpace(sds s) {
+    struct sdshdr *sh;
+
+    sh = (void*) (s-sizeof *sh);;
+    sh = realloc(sh, sizeof *sh+sh->len+1);
+    sh->free = 0;
+    return sh->buf;
+}
+
+/* Return the total size of the allocation of the specifed sds string,
+ * including:
+ * 1) The sds header before the pointer.
+ * 2) The string.
+ * 3) The free buffer at the end if any.
+ * 4) The implicit null term.
+ */
+size_t sdsAllocSize(sds s) {
+    struct sdshdr *sh = (void*) (s-sizeof *sh);;
+
+    return sizeof(*sh)+sh->len+sh->free+1;
+}
+
+/* Increment the sds length and decrements the left free space at the
+ * end of the string according to 'incr'. Also set the null term
+ * in the new end of the string.
+ *
+ * This function is used in order to fix the string length after the
+ * user calls sdsMakeRoomFor(), writes something after the end of
+ * the current string, and finally needs to set the new length.
+ *
+ * Note: it is possible to use a negative increment in order to
+ * right-trim the string.
+ *
+ * Usage example:
+ *
+ * Using sdsIncrLen() and sdsMakeRoomFor() it is possible to mount the
+ * following schema, to cat bytes coming from the kernel to the end of an
+ * sds string without copying into an intermediate buffer:
+ *
+ * oldlen = sdslen(s);
+ * s = sdsMakeRoomFor(s, BUFFER_SIZE);
+ * nread = read(fd, s+oldlen, BUFFER_SIZE);
+ * ... check for nread <= 0 and handle it ...
+ * sdsIncrLen(s, nread);
+ */
+void sdsIncrLen(sds s, int incr) {
+    struct sdshdr *sh = (void*) (s-sizeof *sh);;
+
+    assert(sh->free >= incr);
+    sh->len += incr;
+    sh->free -= incr;
+    assert(sh->free >= 0);
+    s[sh->len] = '\0';
+}
+
 /* Grow the sds to have the specified length. Bytes that were not part of
- * the original length of the sds will be set to zero. */
+ * the original length of the sds will be set to zero.
+ *
+ * if the specified length is smaller than the current length, no operation
+ * is performed. */
 sds sdsgrowzero(sds s, size_t len) {
-    struct sdshdr *sh = (void*)(s-(sizeof(struct sdshdr)));
+    struct sdshdr *sh = (void*) (s-sizeof *sh);
     size_t totlen, curlen = sh->len;
 
     if (len <= curlen) return s;
@@ -116,7 +221,7 @@ sds sdsgrowzero(sds s, size_t len) {
     if (s == NULL) return NULL;
 
     /* Make sure added region doesn't contain garbage */
-    sh = (void*)(s-(sizeof(struct sdshdr)));
+    sh = (void*)(s-sizeof *sh);
     memset(s+curlen,0,(len-curlen+1)); /* also set trailing \0 byte */
     totlen = sh->len+sh->free;
     sh->len = len;
@@ -124,13 +229,18 @@ sds sdsgrowzero(sds s, size_t len) {
     return s;
 }
 
+/* Append the specified binary-safe string pointed by 't' of 'len' bytes to the
+ * end of the specified sds string 's'.
+ *
+ * After the call, the passed sds string is no longer valid and all the
+ * references must be substituted with the new pointer returned by the call. */
 sds sdscatlen(sds s, const void *t, size_t len) {
     struct sdshdr *sh;
     size_t curlen = sdslen(s);
 
     s = sdsMakeRoomFor(s,len);
     if (s == NULL) return NULL;
-    sh = (void*) (s-(sizeof(struct sdshdr)));
+    sh = (void*) (s-sizeof *sh);;
     memcpy(s+curlen, t, len);
     sh->len = curlen+len;
     sh->free = sh->free-len;
@@ -138,18 +248,32 @@ sds sdscatlen(sds s, const void *t, size_t len) {
     return s;
 }
 
+/* Append the specified null termianted C string to the sds string 's'.
+ *
+ * After the call, the passed sds string is no longer valid and all the
+ * references must be substituted with the new pointer returned by the call. */
 sds sdscat(sds s, const char *t) {
     return sdscatlen(s, t, strlen(t));
 }
 
-sds sdscpylen(sds s, char *t, size_t len) {
-    struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
+/* Append the specified sds 't' to the existing sds 's'.
+ *
+ * After the call, the modified sds string is no longer valid and all the
+ * references must be substituted with the new pointer returned by the call. */
+sds sdscatsds(sds s, const sds t) {
+    return sdscatlen(s, t, sdslen(t));
+}
+
+/* Destructively modify the sds string 's' to hold the specified binary
+ * safe string pointed by 't' of length 'len' bytes. */
+sds sdscpylen(sds s, const char *t, size_t len) {
+    struct sdshdr *sh = (void*) (s-sizeof *sh);;
     size_t totlen = sh->free+sh->len;
 
     if (totlen < len) {
         s = sdsMakeRoomFor(s,len-sh->len);
         if (s == NULL) return NULL;
-        sh = (void*) (s-(sizeof(struct sdshdr)));
+        sh = (void*) (s-sizeof *sh);;
         totlen = sh->free+sh->len;
     }
     memcpy(s, t, len);
@@ -159,10 +283,13 @@ sds sdscpylen(sds s, char *t, size_t len) {
     return s;
 }
 
-sds sdscpy(sds s, char *t) {
+/* Like sdscpylen() but 't' must be a null-termined string so that the length
+ * of the string is obtained with strlen(). */
+sds sdscpy(sds s, const char *t) {
     return sdscpylen(s, t, strlen(t));
 }
 
+/* Like sdscatpritf() but gets va_list instead of being variadic. */
 sds sdscatvprintf(sds s, const char *fmt, va_list ap) {
     va_list cpy;
     char *buf, *t;
@@ -170,15 +297,10 @@ sds sdscatvprintf(sds s, const char *fmt, va_list ap) {
 
     while(1) {
         buf = malloc(buflen);
-#ifdef SDS_ABORT_ON_OOM
-        if (buf == NULL) sdsOomAbort();
-#else
         if (buf == NULL) return NULL;
-#endif
         buf[buflen-2] = '\0';
         va_copy(cpy,ap);
         vsnprintf(buf, buflen, fmt, cpy);
-        va_end(cpy);
         if (buf[buflen-2] != '\0') {
             free(buf);
             buflen *= 2;
@@ -191,6 +313,22 @@ sds sdscatvprintf(sds s, const char *fmt, va_list ap) {
     return t;
 }
 
+/* Append to the sds string 's' a string obtained using printf-alike format
+ * specifier.
+ *
+ * After the call, the modified sds string is no longer valid and all the
+ * references must be substituted with the new pointer returned by the call.
+ *
+ * Example:
+ *
+ * s = sdsempty("Sum is: ");
+ * s = sdscatprintf(s,"%d+%d = %d",a,b,a+b).
+ *
+ * Often you need to create a string from scratch with the printf-alike
+ * format. When this is the need, just use sdsempty() as the target string:
+ *
+ * s = sdscatprintf(sdsempty(), "... your format ...", args);
+ */
 sds sdscatprintf(sds s, const char *fmt, ...) {
     va_list ap;
     char *t;
@@ -200,8 +338,22 @@ sds sdscatprintf(sds s, const char *fmt, ...) {
     return t;
 }
 
-sds sdstrim(sds s, const char *cset) {
-    struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
+/* Remove the part of the string from left and from right composed just of
+ * contiguous characters found in 'cset', that is a null terminted C string.
+ *
+ * After the call, the modified sds string is no longer valid and all the
+ * references must be substituted with the new pointer returned by the call.
+ *
+ * Example:
+ *
+ * s = sdsnew("AA...AA.a.aa.aHelloWorld     :::");
+ * s = sdstrim(s,"A. :");
+ * printf("%s\n", s);
+ *
+ * Output will be just "Hello World".
+ */
+void sdstrim(sds s, const char *cset) {
+    struct sdshdr *sh = (void*) (s-sizeof *sh);;
     char *start, *end, *sp, *ep;
     size_t len;
 
@@ -214,14 +366,29 @@ sds sdstrim(sds s, const char *cset) {
     sh->buf[len] = '\0';
     sh->free = sh->free+(sh->len-len);
     sh->len = len;
-    return s;
 }
 
-sds sdsrange(sds s, int start, int end) {
-    struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
+/* Turn the string into a smaller (or equal) string containing only the
+ * substring specified by the 'start' and 'end' indexes.
+ *
+ * start and end can be negative, where -1 means the last character of the
+ * string, -2 the penultimate character, and so forth.
+ *
+ * The interval is inclusive, so the start and end characters will be part
+ * of the resulting string.
+ *
+ * The string is modified in-place.
+ *
+ * Example:
+ *
+ * s = sdsnew("Hello World");
+ * sdsrange(s,1,-1); => "ello World"
+ */
+void sdsrange(sds s, int start, int end) {
+    struct sdshdr *sh = (void*) (s-sizeof *sh);;
     size_t newlen, len = sdslen(s);
 
-    if (len == 0) return s;
+    if (len == 0) return;
     if (start < 0) {
         start = len+start;
         if (start < 0) start = 0;
@@ -245,22 +412,34 @@ sds sdsrange(sds s, int start, int end) {
     sh->buf[newlen] = 0;
     sh->free = sh->free+(sh->len-newlen);
     sh->len = newlen;
-    return s;
 }
 
+/* Apply tolower() to every character of the sds string 's'. */
 void sdstolower(sds s) {
     int len = sdslen(s), j;
 
     for (j = 0; j < len; j++) s[j] = tolower(s[j]);
 }
 
+/* Apply toupper() to every character of the sds string 's'. */
 void sdstoupper(sds s) {
     int len = sdslen(s), j;
 
     for (j = 0; j < len; j++) s[j] = toupper(s[j]);
 }
 
-int sdscmp(sds s1, sds s2) {
+/* Compare two sds strings s1 and s2 with memcmp().
+ *
+ * Return value:
+ *
+ *     1 if s1 > s2.
+ *    -1 if s1 < s2.
+ *     0 if s1 and s2 are exactly the same binary string.
+ *
+ * If two strings share exactly the same prefix, but one of the two has
+ * additional characters, the longer string is considered to be greater than
+ * the smaller one. */
+int sdscmp(const sds s1, const sds s2) {
     size_t l1, l2, minlen;
     int cmp;
 
@@ -288,18 +467,15 @@ int sdscmp(sds s1, sds s2) {
  * requires length arguments. sdssplit() is just the
  * same function but for zero-terminated strings.
  */
-sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count) {
+sds *sdssplitlen(const char *s, int len, const char *sep, int seplen, int *count) {
     int elements = 0, slots = 5, start = 0, j;
+    sds *tokens;
 
-    sds *tokens = malloc(sizeof(sds)*slots);
-#ifdef SDS_ABORT_ON_OOM
-    if (tokens == NULL) sdsOomAbort();
-#endif
+    if (seplen < 1 || len < 0) return NULL;
+
+    tokens = malloc(sizeof(sds)*slots);
     if (tokens == NULL) return NULL;
-    if (seplen < 1 || len < 0) {
-        free(tokens);
-        return NULL;
-    }
+
     if (len == 0) {
         *count = 0;
         return tokens;
@@ -311,25 +487,13 @@ sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count) {
 
             slots *= 2;
             newtokens = realloc(tokens,sizeof(sds)*slots);
-            if (newtokens == NULL) {
-#ifdef SDS_ABORT_ON_OOM
-                sdsOomAbort();
-#else
-                goto cleanup;
-#endif
-            }
+            if (newtokens == NULL) goto cleanup;
             tokens = newtokens;
         }
         /* search the separator */
         if ((seplen == 1 && *(s+j) == sep[0]) || (memcmp(s+j,sep,seplen) == 0)) {
             tokens[elements] = sdsnewlen(s+start,j-start);
-            if (tokens[elements] == NULL) {
-#ifdef SDS_ABORT_ON_OOM
-                sdsOomAbort();
-#else
-                goto cleanup;
-#endif
-            }
+            if (tokens[elements] == NULL) goto cleanup;
             elements++;
             start = j+seplen;
             j = j+seplen-1; /* skip the separator */
@@ -337,28 +501,22 @@ sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count) {
     }
     /* Add the final element. We are sure there is room in the tokens array. */
     tokens[elements] = sdsnewlen(s+start,len-start);
-    if (tokens[elements] == NULL) {
-#ifdef SDS_ABORT_ON_OOM
-                sdsOomAbort();
-#else
-                goto cleanup;
-#endif
-    }
+    if (tokens[elements] == NULL) goto cleanup;
     elements++;
     *count = elements;
     return tokens;
 
-#ifndef SDS_ABORT_ON_OOM
 cleanup:
     {
         int i;
         for (i = 0; i < elements; i++) sdsfree(tokens[i]);
         free(tokens);
+        *count = 0;
         return NULL;
     }
-#endif
 }
 
+/* Free the result returned by sdssplitlen(), or do nothing if 'tokens' is NULL. */
 void sdsfreesplitres(sds *tokens, int count) {
     if (!tokens) return;
     while(count--)
@@ -366,6 +524,10 @@ void sdsfreesplitres(sds *tokens, int count) {
     free(tokens);
 }
 
+/* Create an sds string from a long long value. It is much faster than:
+ *
+ * sdscatprintf(sdsempty(),"%lld\n", value);
+ */
 sds sdsfromlonglong(long long value) {
     char buf[32], *p;
     unsigned long long v;
@@ -381,10 +543,14 @@ sds sdsfromlonglong(long long value) {
     return sdsnewlen(p,32-(p-buf));
 }
 
-sds sdscatrepr(sds s, char *p, size_t len) {
+/* Append to the sds string "s" an escaped string representation where
+ * all the non-printable characters (tested with isprint()) are turned into
+ * escapes in the form "\n\r\a...." or "\x<hex-number>".
+ *
+ * After the call, the modified sds string is no longer valid and all the
+ * references must be substituted with the new pointer returned by the call. */
+sds sdscatrepr(sds s, const char *p, size_t len) {
     s = sdscatlen(s,"\"",1);
-    if (s == NULL) return NULL;
-
     while(len--) {
         switch(*p) {
         case '\\':
@@ -404,27 +570,64 @@ sds sdscatrepr(sds s, char *p, size_t len) {
             break;
         }
         p++;
-        if (s == NULL) return NULL;
     }
     return sdscatlen(s,"\"",1);
 }
 
+/* Helper function for sdssplitargs() that returns non zero if 'c'
+ * is a valid hex digit. */
+int is_hex_digit(char c) {
+    return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') ||
+           (c >= 'A' && c <= 'F');
+}
+
+/* Helper function for sdssplitargs() that converts a hex digit into an
+ * integer from 0 to 15 */
+int hex_digit_to_int(char c) {
+    switch(c) {
+    case '0': return 0;
+    case '1': return 1;
+    case '2': return 2;
+    case '3': return 3;
+    case '4': return 4;
+    case '5': return 5;
+    case '6': return 6;
+    case '7': return 7;
+    case '8': return 8;
+    case '9': return 9;
+    case 'a': case 'A': return 10;
+    case 'b': case 'B': return 11;
+    case 'c': case 'C': return 12;
+    case 'd': case 'D': return 13;
+    case 'e': case 'E': return 14;
+    case 'f': case 'F': return 15;
+    default: return 0;
+    }
+}
+
 /* Split a line into arguments, where every argument can be in the
  * following programming-language REPL-alike form:
  *
  * foo bar "newline are supported\n" and "\xff\x00otherstuff"
  *
  * The number of arguments is stored into *argc, and an array
- * of sds is returned. The caller should sdsfree() all the returned
- * strings and finally free() the array itself.
+ * of sds is returned.
+ *
+ * The caller should free the resulting array of sds strings with
+ * sdsfreesplitres().
  *
  * Note that sdscatrepr() is able to convert back a string into
  * a quoted string in the same format sdssplitargs() is able to parse.
+ *
+ * The function returns the allocated tokens on success, even when the
+ * input string is empty, or NULL if the input contains unbalanced
+ * quotes or closed quotes followed by non space characters
+ * as in: "foo"bar or "foo'
  */
-sds *sdssplitargs(char *line, int *argc) {
-    char *p = line;
+sds *sdssplitargs(const char *line, int *argc) {
+    const char *p = line;
     char *current = NULL;
-    char **vector = NULL, **_vector = NULL;
+    char **vector = NULL;
 
     *argc = 0;
     while(1) {
@@ -432,17 +635,24 @@ sds *sdssplitargs(char *line, int *argc) {
         while(*p && isspace(*p)) p++;
         if (*p) {
             /* get a token */
-            int inq=0; /* set to 1 if we are in "quotes" */
+            int inq=0;  /* set to 1 if we are in "quotes" */
+            int insq=0; /* set to 1 if we are in 'single quotes' */
             int done=0;
 
-            if (current == NULL) {
-                current = sdsempty();
-                if (current == NULL) goto err;
-            }
-
+            if (current == NULL) current = sdsempty();
             while(!done) {
                 if (inq) {
-                    if (*p == '\\' && *(p+1)) {
+                    if (*p == '\\' && *(p+1) == 'x' &&
+                                             is_hex_digit(*(p+2)) &&
+                                             is_hex_digit(*(p+3)))
+                    {
+                        unsigned char byte;
+
+                        byte = (hex_digit_to_int(*(p+2))*16)+
+                                hex_digit_to_int(*(p+3));
+                        current = sdscatlen(current,(char*)&byte,1);
+                        p += 3;
+                    } else if (*p == '\\' && *(p+1)) {
                         char c;
 
                         p++;
@@ -456,7 +666,23 @@ sds *sdssplitargs(char *line, int *argc) {
                         }
                         current = sdscatlen(current,&c,1);
                     } else if (*p == '"') {
-                        /* closing quote must be followed by a space */
+                        /* closing quote must be followed by a space or
+                         * nothing at all. */
+                        if (*(p+1) && !isspace(*(p+1))) goto err;
+                        done=1;
+                    } else if (!*p) {
+                        /* unterminated quotes */
+                        goto err;
+                    } else {
+                        current = sdscatlen(current,p,1);
+                    }
+                } else if (insq) {
+                    if (*p == '\\' && *(p+1) == '\'') {
+                        p++;
+                        current = sdscatlen(current,"'",1);
+                    } else if (*p == '\'') {
+                        /* closing quote must be followed by a space or
+                         * nothing at all. */
                         if (*(p+1) && !isspace(*(p+1))) goto err;
                         done=1;
                     } else if (!*p) {
@@ -477,23 +703,24 @@ sds *sdssplitargs(char *line, int *argc) {
                     case '"':
                         inq=1;
                         break;
+                    case '\'':
+                        insq=1;
+                        break;
                     default:
                         current = sdscatlen(current,p,1);
                         break;
                     }
                 }
                 if (*p) p++;
-                if (current == NULL) goto err;
             }
             /* add the token to the vector */
-            _vector = realloc(vector,((*argc)+1)*sizeof(char*));
-            if (_vector == NULL) goto err;
-
-            vector = _vector;
+            vector = realloc(vector,((*argc)+1)*sizeof(char*));
             vector[*argc] = current;
             (*argc)++;
             current = NULL;
         } else {
+            /* Even on empty input string return something not NULL. */
+            if (vector == NULL) vector = malloc(sizeof(void*));
             return vector;
         }
     }
@@ -501,30 +728,67 @@ sds *sdssplitargs(char *line, int *argc) {
 err:
     while((*argc)--)
         sdsfree(vector[*argc]);
-    if (vector != NULL) free(vector);
-    if (current != NULL) sdsfree(current);
+    free(vector);
+    if (current) sdsfree(current);
+    *argc = 0;
     return NULL;
 }
 
+/* Modify the string substituting all the occurrences of the set of
+ * characters specified in the 'from' string to the corresponding character
+ * in the 'to' array.
+ *
+ * For instance: sdsmapchars(mystring, "ho", "01", 2)
+ * will have the effect of turning the string "hello" into "0ell1".
+ *
+ * The function returns the sds string pointer, that is always the same
+ * as the input pointer since no resize is needed. */
+sds sdsmapchars(sds s, const char *from, const char *to, size_t setlen) {
+    size_t j, i, l = sdslen(s);
+
+    for (j = 0; j < l; j++) {
+        for (i = 0; i < setlen; i++) {
+            if (s[j] == from[i]) {
+                s[j] = to[i];
+                break;
+            }
+        }
+    }
+    return s;
+}
+
+/* Join an array of C strings using the specified separator (also a C string).
+ * Returns the result as an sds string. */
+sds sdsjoin(char **argv, int argc, char *sep, size_t seplen) {
+    sds join = sdsempty();
+    int j;
+
+    for (j = 0; j < argc; j++) {
+        join = sdscat(join, argv[j]);
+        if (j != argc-1) join = sdscatlen(join,sep,seplen);
+    }
+    return join;
+}
+
+/* Like sdsjoin, but joins an array of SDS strings. */
+sds sdsjoinsds(sds *argv, int argc, const char *sep, size_t seplen) {
+    sds join = sdsempty();
+    int j;
+
+    for (j = 0; j < argc; j++) {
+        join = sdscatsds(join, argv[j]);
+        if (j != argc-1) join = sdscatlen(join,sep,seplen);
+    }
+    return join;
+}
+
 #ifdef SDS_TEST_MAIN
 #include <stdio.h>
-
-int __failed_tests = 0;
-int __test_num = 0;
-#define test_cond(descr,_c) do { \
-    __test_num++; printf("%d - %s: ", __test_num, descr); \
-    if(_c) printf("PASSED\n"); else {printf("FAILED\n"); __failed_tests++;} \
-} while(0);
-#define test_report() do { \
-    printf("%d tests, %d passed, %d failed\n", __test_num, \
-                    __test_num-__failed_tests, __failed_tests); \
-    if (__failed_tests) { \
-        printf("=== WARNING === We have failed tests here...\n"); \
-    } \
-} while(0);
+#include "testhelp.h"
 
 int main(void) {
     {
+        struct sdshdr *sh;
         sds x = sdsnew("foo"), y;
 
         test_cond("Create a string and obtain the length",
@@ -554,36 +818,43 @@ int main(void) {
             sdslen(x) == 3 && memcmp(x,"123\0",4) ==0)
 
         sdsfree(x);
-        x = sdstrim(sdsnew("xxciaoyyy"),"xy");
+        x = sdsnew("xxciaoyyy");
+        sdstrim(x,"xy");
         test_cond("sdstrim() correctly trims characters",
             sdslen(x) == 4 && memcmp(x,"ciao\0",5) == 0)
 
-        y = sdsrange(sdsdup(x),1,1);
+        y = sdsdup(x);
+        sdsrange(y,1,1);
         test_cond("sdsrange(...,1,1)",
             sdslen(y) == 1 && memcmp(y,"i\0",2) == 0)
 
         sdsfree(y);
-        y = sdsrange(sdsdup(x),1,-1);
+        y = sdsdup(x);
+        sdsrange(y,1,-1);
         test_cond("sdsrange(...,1,-1)",
             sdslen(y) == 3 && memcmp(y,"iao\0",4) == 0)
 
         sdsfree(y);
-        y = sdsrange(sdsdup(x),-2,-1);
+        y = sdsdup(x);
+        sdsrange(y,-2,-1);
         test_cond("sdsrange(...,-2,-1)",
             sdslen(y) == 2 && memcmp(y,"ao\0",3) == 0)
 
         sdsfree(y);
-        y = sdsrange(sdsdup(x),2,1);
+        y = sdsdup(x);
+        sdsrange(y,2,1);
         test_cond("sdsrange(...,2,1)",
             sdslen(y) == 0 && memcmp(y,"\0",1) == 0)
 
         sdsfree(y);
-        y = sdsrange(sdsdup(x),1,100);
+        y = sdsdup(x);
+        sdsrange(y,1,100);
         test_cond("sdsrange(...,1,100)",
             sdslen(y) == 3 && memcmp(y,"iao\0",4) == 0)
 
         sdsfree(y);
-        y = sdsrange(sdsdup(x),100,100);
+        y = sdsdup(x);
+        sdsrange(y,100,100);
         test_cond("sdsrange(...,100,100)",
             sdslen(y) == 0 && memcmp(y,"\0",1) == 0)
 
@@ -604,7 +875,33 @@ int main(void) {
         x = sdsnew("aar");
         y = sdsnew("bar");
         test_cond("sdscmp(bar,bar)", sdscmp(x,y) < 0)
+
+        sdsfree(y);
+        sdsfree(x);
+        x = sdsnewlen("\a\n\0foo\r",7);
+        y = sdscatrepr(sdsempty(),x,sdslen(x));
+        test_cond("sdscatrepr(...data...)",
+            memcmp(y,"\"\\a\\n\\x00foo\\r\"",15) == 0)
+
+        {
+            int oldfree;
+
+            sdsfree(x);
+            x = sdsnew("0");
+            sh = (void*) (x-(sizeof(struct sdshdr)));
+            test_cond("sdsnew() free/len buffers", sh->len == 1 && sh->free == 0);
+            x = sdsMakeRoomFor(x,1);
+            sh = (void*) (x-(sizeof(struct sdshdr)));
+            test_cond("sdsMakeRoomFor()", sh->len == 1 && sh->free > 0);
+            oldfree = sh->free;
+            x[1] = '1';
+            sdsIncrLen(x,1);
+            test_cond("sdsIncrLen() -- content", x[0] == '0' && x[1] == '1');
+            test_cond("sdsIncrLen() -- len", sh->len == 2);
+            test_cond("sdsIncrLen() -- free", sh->free == oldfree-1);
+        }
     }
     test_report()
+    return 0;
 }
 #endif
diff --git a/sds.h b/sds.h
index 94f5871..ab6fc9c 100644
--- a/sds.h
+++ b/sds.h
@@ -1,6 +1,6 @@
-/* SDSLib, A C dynamic strings library
+/* SDS (Simple Dynamic Strings), A C dynamic strings library.
  *
- * Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2006-2014, Salvatore Sanfilippo <antirez at gmail dot com>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -31,6 +31,8 @@
 #ifndef __SDS_H
 #define __SDS_H
 
+#define SDS_MAX_PREALLOC (1024*1024)
+
 #include <sys/types.h>
 #include <stdarg.h>
 
@@ -43,12 +45,12 @@ struct sdshdr {
 };
 
 static inline size_t sdslen(const sds s) {
-    struct sdshdr *sh = (void*)(s-(sizeof(struct sdshdr)));
+    struct sdshdr *sh = (void*)(s-sizeof *sh);
     return sh->len;
 }
 
 static inline size_t sdsavail(const sds s) {
-    struct sdshdr *sh = (void*)(s-(sizeof(struct sdshdr)));
+    struct sdshdr *sh = (void*)(s-sizeof *sh);
     return sh->free;
 }
 
@@ -58,12 +60,13 @@ sds sdsempty(void);
 size_t sdslen(const sds s);
 sds sdsdup(const sds s);
 void sdsfree(sds s);
-size_t sdsavail(sds s);
+size_t sdsavail(const sds s);
 sds sdsgrowzero(sds s, size_t len);
 sds sdscatlen(sds s, const void *t, size_t len);
 sds sdscat(sds s, const char *t);
-sds sdscpylen(sds s, char *t, size_t len);
-sds sdscpy(sds s, char *t);
+sds sdscatsds(sds s, const sds t);
+sds sdscpylen(sds s, const char *t, size_t len);
+sds sdscpy(sds s, const char *t);
 
 sds sdscatvprintf(sds s, const char *fmt, va_list ap);
 #ifdef __GNUC__
@@ -73,16 +76,26 @@ sds sdscatprintf(sds s, const char *fmt, ...)
 sds sdscatprintf(sds s, const char *fmt, ...);
 #endif
 
-sds sdstrim(sds s, const char *cset);
-sds sdsrange(sds s, int start, int end);
+void sdstrim(sds s, const char *cset);
+void sdsrange(sds s, int start, int end);
 void sdsupdatelen(sds s);
-int sdscmp(sds s1, sds s2);
-sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count);
+void sdsclear(sds s);
+int sdscmp(const sds s1, const sds s2);
+sds *sdssplitlen(const char *s, int len, const char *sep, int seplen, int *count);
 void sdsfreesplitres(sds *tokens, int count);
 void sdstolower(sds s);
 void sdstoupper(sds s);
 sds sdsfromlonglong(long long value);
-sds sdscatrepr(sds s, char *p, size_t len);
-sds *sdssplitargs(char *line, int *argc);
+sds sdscatrepr(sds s, const char *p, size_t len);
+sds *sdssplitargs(const char *line, int *argc);
+sds sdsmapchars(sds s, const char *from, const char *to, size_t setlen);
+sds sdsjoin(char **argv, int argc, char *sep, size_t seplen);
+sds sdsjoinsds(sds *argv, int argc, const char *sep, size_t seplen);
+
+/* Low level functions exposed to the user API */
+sds sdsMakeRoomFor(sds s, size_t addlen);
+void sdsIncrLen(sds s, int incr);
+sds sdsRemoveFreeSpace(sds s);
+size_t sdsAllocSize(sds s);
 
 #endif
diff --git a/test.c b/test.c
index b3b806f..713cc06 100644
--- a/test.c
+++ b/test.c
@@ -14,7 +14,8 @@
 
 enum connection_type {
     CONN_TCP,
-    CONN_UNIX
+    CONN_UNIX,
+    CONN_FD
 };
 
 struct config {
@@ -64,7 +65,7 @@ static redisContext *select_database(redisContext *c) {
     return c;
 }
 
-static void disconnect(redisContext *c) {
+static int disconnect(redisContext *c, int keep_fd) {
     redisReply *reply;
 
     /* Make sure we're on DB 9. */
@@ -75,8 +76,11 @@ static void disconnect(redisContext *c) {
     assert(reply != NULL);
     freeReplyObject(reply);
 
-    /* Free the context as well. */
+    /* Free the context as well, but keep the fd if requested. */
+    if (keep_fd)
+        return redisFreeKeepFd(c);
     redisFree(c);
+    return -1;
 }
 
 static redisContext *connect(struct config config) {
@@ -86,6 +90,14 @@ static redisContext *connect(struct config config) {
         c = redisConnect(config.tcp.host, config.tcp.port);
     } else if (config.type == CONN_UNIX) {
         c = redisConnectUnix(config.unix.path);
+    } else if (config.type == CONN_FD) {
+        /* Create a dummy connection just to get an fd to inherit */
+        redisContext *dummy_ctx = redisConnectUnix(config.unix.path);
+        if (dummy_ctx) {
+            int fd = disconnect(dummy_ctx, 1);
+            printf("Connecting to inherited fd %d\n", fd);
+            c = redisConnectFd(fd);
+        }
     } else {
         assert(NULL);
     }
@@ -205,6 +217,28 @@ static void test_format_commands(void) {
     free(cmd);
 }
 
+static void test_append_formatted_commands(struct config config) {
+    redisContext *c;
+    redisReply *reply;
+    char *cmd;
+    int len;
+
+    c = connect(config);
+
+    test("Append format command: ");
+
+    len = redisFormatCommand(&cmd, "SET foo bar");
+
+    test_cond(redisAppendFormattedCommand(c, cmd, len) == REDIS_OK);
+
+    assert(redisGetReply(c, (void*)&reply) == REDIS_OK);
+
+    free(cmd);
+    freeReplyObject(reply);
+
+    disconnect(c, 0);
+}
+
 static void test_reply_reader(void) {
     redisReader *reader;
     void *reply;
@@ -293,6 +327,7 @@ static void test_blocking_connection_errors(void) {
         (strcmp(c->errstr,"Name or service not known") == 0 ||
          strcmp(c->errstr,"Can't resolve: idontexist.local") == 0 ||
          strcmp(c->errstr,"nodename nor servname provided, or not known") == 0 ||
+         strcmp(c->errstr,"No address associated with hostname") == 0 ||
          strcmp(c->errstr,"no address associated with name") == 0));
     redisFree(c);
 
@@ -383,7 +418,7 @@ static void test_blocking_connection(struct config config) {
               strcasecmp(reply->element[1]->str,"pong") == 0);
     freeReplyObject(reply);
 
-    disconnect(c);
+    disconnect(c, 0);
 }
 
 static void test_blocking_io_errors(struct config config) {
@@ -523,7 +558,7 @@ static void test_throughput(struct config config) {
     free(replies);
     printf("\t(%dx LRANGE with 500 elements (pipelined): %.3fs)\n", num, (t2-t1)/1000000.0);
 
-    disconnect(c);
+    disconnect(c, 0);
 }
 
 // static long __test_callback_flags = 0;
@@ -636,6 +671,7 @@ int main(int argc, char **argv) {
         }
     };
     int throughput = 1;
+    int test_inherit_fd = 1;
 
     /* Ignore broken pipe signal (for I/O error tests). */
     signal(SIGPIPE, SIG_IGN);
@@ -654,6 +690,8 @@ int main(int argc, char **argv) {
             cfg.unix.path = argv[0];
         } else if (argc >= 1 && !strcmp(argv[0],"--skip-throughput")) {
             throughput = 0;
+        } else if (argc >= 1 && !strcmp(argv[0],"--skip-inherit-fd")) {
+            test_inherit_fd = 0;
         } else {
             fprintf(stderr, "Invalid argument: %s\n", argv[0]);
             exit(1);
@@ -670,6 +708,7 @@ int main(int argc, char **argv) {
     test_blocking_connection(cfg);
     test_blocking_io_errors(cfg);
     test_invalid_timeout_errors(cfg);
+    test_append_formatted_commands(cfg);
     if (throughput) test_throughput(cfg);
 
     printf("\nTesting against Unix socket connection (%s):\n", cfg.unix.path);
@@ -678,6 +717,12 @@ int main(int argc, char **argv) {
     test_blocking_io_errors(cfg);
     if (throughput) test_throughput(cfg);
 
+    if (test_inherit_fd) {
+        printf("\nTesting against inherited fd (%s):\n", cfg.unix.path);
+        cfg.type = CONN_FD;
+        test_blocking_connection(cfg);
+    }
+
     if (fails) {
         printf("*** %d TESTS FAILED ***\n", fails);
         return 1;