* |11111111| - End of ziplist.
*
* All the integers are represented in little endian byte order.
+ *
+ * ----------------------------------------------------------------------------
+ *
+ * Copyright (c) 2009-2012, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ * Copyright (c) 2009-2012, 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 <stdio.h>
totlen = p-first.p;
if (totlen > 0) {
if (p[0] != ZIP_END) {
- /* Tricky: storing the prevlen in this entry might reduce or
- * increase the number of bytes needed, compared to the current
- * prevlen. Note that we can always store this length because
- * it was previously stored by an entry that is being deleted. */
+ /* Storing `prevrawlen` in this entry may increase or decrease the
+ * number of bytes required compare to the current `prevrawlen`.
+ * There always is room to store this, because it was previously
+ * stored by an entry that is now being deleted. */
nextdiff = zipPrevLenByteDiff(p,first.prevrawlen);
- zipPrevEncodeLength(p-nextdiff,first.prevrawlen);
+ p -= nextdiff;
+ zipPrevEncodeLength(p,first.prevrawlen);
/* Update offset for tail */
ZIPLIST_TAIL_OFFSET(zl) =
}
/* Move tail to the front of the ziplist */
- memmove(first.p,p-nextdiff,
- intrev32ifbe(ZIPLIST_BYTES(zl))-(p-zl)-1+nextdiff);
+ memmove(first.p,p,
+ intrev32ifbe(ZIPLIST_BYTES(zl))-(p-zl)-1);
} else {
/* The entire tail was deleted. No need to move memory. */
ZIPLIST_TAIL_OFFSET(zl) =