X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/0f3dfa87bc8870c1da6867b7e2d9d70f7e21fc93..b8b8501d70770465adc67d4effb4dbae2899f3a8:/ziplist.c?ds=sidebyside

diff --git a/ziplist.c b/ziplist.c
index 71d965a8..4b9d0fad 100644
--- a/ziplist.c
+++ b/ziplist.c
@@ -17,10 +17,10 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <stdint.h>
 #include <assert.h>
 #include <limits.h>
 #include "zmalloc.h"
-#include "sds.h"
 #include "ziplist.h"
 
 /* Important note: the ZIP_END value is used to depict the end of the
@@ -33,9 +33,9 @@
 
 /* Entry encoding */
 #define ZIP_ENC_RAW     0
-#define ZIP_ENC_SHORT   1
-#define ZIP_ENC_INT     2
-#define ZIP_ENC_LLONG   3
+#define ZIP_ENC_INT16   1
+#define ZIP_ENC_INT32   2
+#define ZIP_ENC_INT64   3
 #define ZIP_ENCODING(p) ((p)[0] >> 6)
 
 /* Length encoding for raw entries */
@@ -44,15 +44,18 @@
 #define ZIP_LEN_UINT32  2
 
 /* Utility macros */
-#define ZIPLIST_BYTES(zl) (*((unsigned int*)(zl)))
-#define ZIPLIST_TAIL_OFFSET(zl) (*((zl)+sizeof(unsigned int)))
-#define ZIPLIST_LENGTH(zl) (*((zl)+2*sizeof(unsigned int)))
-#define ZIPLIST_HEADER_SIZE (2*sizeof(unsigned int)+1)
-#define ZIPLIST_ENTRY_HEAD(zl) ((zl)+ZIPLIST_HEADER_SIZE)
-#define ZIPLIST_ENTRY_TAIL(zl) ((zl)+ZIPLIST_TAIL_OFFSET(zl))
-#define ZIPLIST_ENTRY_END(zl) ((zl)+ZIPLIST_BYTES(zl)-1)
+#define ZIPLIST_BYTES(zl)       (*((uint32_t*)(zl)))
+#define ZIPLIST_TAIL_OFFSET(zl) (*((uint32_t*)((zl)+sizeof(uint32_t))))
+#define ZIPLIST_LENGTH(zl)      (*((uint16_t*)((zl)+sizeof(uint32_t)*2)))
+#define ZIPLIST_HEADER_SIZE     (sizeof(uint32_t)*2+sizeof(uint16_t))
+#define ZIPLIST_ENTRY_HEAD(zl)  ((zl)+ZIPLIST_HEADER_SIZE)
+#define ZIPLIST_ENTRY_TAIL(zl)  ((zl)+ZIPLIST_TAIL_OFFSET(zl))
+#define ZIPLIST_ENTRY_END(zl)   ((zl)+ZIPLIST_BYTES(zl)-1)
+
+/* We know a positive increment can only be 1 because entries can only be
+ * pushed one at a time. */
 #define ZIPLIST_INCR_LENGTH(zl,incr) { \
-    if (ZIPLIST_LENGTH(zl) < ZIP_BIGLEN) ZIPLIST_LENGTH(zl)+=incr; }
+    if (ZIPLIST_LENGTH(zl) < UINT16_MAX) ZIPLIST_LENGTH(zl)+=incr; }
 
 typedef struct zlentry {
     unsigned int prevrawlensize, prevrawlen;
@@ -63,13 +66,13 @@ typedef struct zlentry {
 } zlentry;
 
 /* Return bytes needed to store integer encoded by 'encoding' */
-static unsigned int zipEncodingSize(char encoding) {
-    if (encoding == ZIP_ENC_SHORT) {
-        return sizeof(short int);
-    } else if (encoding == ZIP_ENC_INT) {
-        return sizeof(int);
-    } else if (encoding == ZIP_ENC_LLONG) {
-        return sizeof(long long);
+static unsigned int zipEncodingSize(unsigned char encoding) {
+    if (encoding == ZIP_ENC_INT16) {
+        return sizeof(int16_t);
+    } else if (encoding == ZIP_ENC_INT32) {
+        return sizeof(int32_t);
+    } else if (encoding == ZIP_ENC_INT64) {
+        return sizeof(int64_t);
     }
     assert(NULL);
 }
@@ -173,19 +176,19 @@ static int zipPrevLenByteDiff(unsigned char *p, unsigned int len) {
 /* Check if string pointed to by 'entry' can be encoded as an integer.
  * Stores the integer value in 'v' and its encoding in 'encoding'.
  * Warning: this function requires a NULL-terminated string! */
-static int zipTryEncoding(char *entry, long long *v, char *encoding) {
+static int zipTryEncoding(unsigned char *entry, long long *v, unsigned char *encoding) {
     long long value;
     char *eptr;
 
     if (entry[0] == '-' || (entry[0] >= '0' && entry[0] <= '9')) {
-        value = strtoll(entry,&eptr,10);
+        value = strtoll((char*)entry,&eptr,10);
         if (eptr[0] != '\0') return 0;
-        if (value >= SHRT_MIN && value <= SHRT_MAX) {
-            *encoding = ZIP_ENC_SHORT;
-        } else if (value >= INT_MIN && value <= INT_MAX) {
-            *encoding = ZIP_ENC_INT;
+        if (value >= INT16_MIN && value <= INT16_MAX) {
+            *encoding = ZIP_ENC_INT16;
+        } else if (value >= INT32_MIN && value <= INT32_MAX) {
+            *encoding = ZIP_ENC_INT32;
         } else {
-            *encoding = ZIP_ENC_LLONG;
+            *encoding = ZIP_ENC_INT64;
         }
         *v = value;
         return 1;
@@ -194,38 +197,38 @@ static int zipTryEncoding(char *entry, long long *v, char *encoding) {
 }
 
 /* Store integer 'value' at 'p', encoded as 'encoding' */
-static void zipSaveInteger(unsigned char *p, long long value, char encoding) {
-    short int s;
-    int i;
-    long long l;
-    if (encoding == ZIP_ENC_SHORT) {
-        s = value;
-        memcpy(p,&s,sizeof(s));
-    } else if (encoding == ZIP_ENC_INT) {
-        i = value;
-        memcpy(p,&i,sizeof(i));
-    } else if (encoding == ZIP_ENC_LLONG) {
-        l = value;
-        memcpy(p,&l,sizeof(l));
+static void zipSaveInteger(unsigned char *p, int64_t value, unsigned char encoding) {
+    int16_t i16;
+    int32_t i32;
+    int64_t i64;
+    if (encoding == ZIP_ENC_INT16) {
+        i16 = value;
+        memcpy(p,&i16,sizeof(i16));
+    } else if (encoding == ZIP_ENC_INT32) {
+        i32 = value;
+        memcpy(p,&i32,sizeof(i32));
+    } else if (encoding == ZIP_ENC_INT64) {
+        i64 = value;
+        memcpy(p,&i64,sizeof(i64));
     } else {
         assert(NULL);
     }
 }
 
 /* Read integer encoded as 'encoding' from 'p' */
-static long long zipLoadInteger(unsigned char *p, char encoding) {
-    short int s;
-    int i;
-    long long l, ret;
-    if (encoding == ZIP_ENC_SHORT) {
-        memcpy(&s,p,sizeof(s));
-        ret = s;
-    } else if (encoding == ZIP_ENC_INT) {
-        memcpy(&i,p,sizeof(i));
-        ret = i;
-    } else if (encoding == ZIP_ENC_LLONG) {
-        memcpy(&l,p,sizeof(l));
-        ret = l;
+static int64_t zipLoadInteger(unsigned char *p, unsigned char encoding) {
+    int16_t i16;
+    int32_t i32;
+    int64_t i64, ret;
+    if (encoding == ZIP_ENC_INT16) {
+        memcpy(&i16,p,sizeof(i16));
+        ret = i16;
+    } else if (encoding == ZIP_ENC_INT32) {
+        memcpy(&i32,p,sizeof(i32));
+        ret = i32;
+    } else if (encoding == ZIP_ENC_INT64) {
+        memcpy(&i64,p,sizeof(i64));
+        ret = i64;
     } else {
         assert(NULL);
     }
@@ -269,7 +272,7 @@ static unsigned char *ziplistResize(unsigned char *zl, unsigned int len) {
 }
 
 /* Delete "num" entries, starting at "p". Returns pointer to the ziplist. */
-static unsigned char *__ziplistDelete(unsigned char *zl, unsigned char *p, int num) {
+static unsigned char *__ziplistDelete(unsigned char *zl, unsigned char *p, unsigned int num) {
     unsigned int i, totlen, deleted = 0;
     int nextdiff = 0;
     zlentry first = zipEntry(p);
@@ -306,11 +309,11 @@ static unsigned char *__ziplistDelete(unsigned char *zl, unsigned char *p, int n
 }
 
 /* Insert item at "p". */
-static unsigned char *__ziplistInsert(unsigned char *zl, unsigned char *p, char *s, unsigned int slen) {
+static unsigned char *__ziplistInsert(unsigned char *zl, unsigned char *p, unsigned char *s, unsigned int slen) {
     unsigned int curlen = ZIPLIST_BYTES(zl), reqlen, prevlen = 0;
     unsigned int offset, nextdiff = 0;
     unsigned char *tail;
-    char encoding = ZIP_ENC_RAW;
+    unsigned char encoding = ZIP_ENC_RAW;
     long long value;
     zlentry entry;
 
@@ -372,36 +375,12 @@ static unsigned char *__ziplistInsert(unsigned char *zl, unsigned char *p, char
     return zl;
 }
 
-unsigned char *ziplistPush(unsigned char *zl, char *s, unsigned int slen, int where) {
+unsigned char *ziplistPush(unsigned char *zl, unsigned char *s, unsigned int slen, int where) {
     unsigned char *p;
     p = (where == ZIPLIST_HEAD) ? ZIPLIST_ENTRY_HEAD(zl) : ZIPLIST_ENTRY_END(zl);
     return __ziplistInsert(zl,p,s,slen);
 }
 
-unsigned char *ziplistPop(unsigned char *zl, sds *target, int where) {
-    zlentry entry;
-    unsigned char *p;
-    long long value;
-    if (target) *target = NULL;
-
-    /* Get pointer to element to remove */
-    p = (where == ZIPLIST_HEAD) ? ZIPLIST_ENTRY_HEAD(zl) : ZIPLIST_ENTRY_TAIL(zl);
-    if (*p == ZIP_END) return zl;
-
-    entry = zipEntry(p);
-    if (target) {
-        if (entry.encoding == ZIP_ENC_RAW) {
-            *target = sdsnewlen(p+entry.headersize,entry.len);
-        } else {
-            value = zipLoadInteger(p+entry.headersize,entry.encoding);
-            *target = sdscatprintf(sdsempty(), "%lld", value);
-        }
-    }
-
-    zl = __ziplistDelete(zl,p,1);
-    return zl;
-}
-
 /* Returns an offset to use for iterating with ziplistNext. When the given
  * index is negative, the list is traversed back to front. When the list
  * doesn't contain an element at the provided index, NULL is returned. */
@@ -428,21 +407,43 @@ unsigned char *ziplistIndex(unsigned char *zl, int index) {
 }
 
 /* Return pointer to next entry in ziplist. */
-unsigned char *ziplistNext(unsigned char *p) {
-    return (p[0] == ZIP_END) ? NULL : p+zipRawEntryLength(p);
+unsigned char *ziplistNext(unsigned char *zl, unsigned char *p) {
+    ((void) zl);
+
+    /* "p" could be equal to ZIP_END, caused by ziplistDelete,
+     * and we should return NULL. Otherwise, we should return NULL
+     * when the *next* element is ZIP_END (there is no next entry). */
+    if (p[0] == ZIP_END) {
+        return NULL;
+    } else {
+        p = p+zipRawEntryLength(p);
+        return (p[0] == ZIP_END) ? NULL : p;
+    }
 }
 
 /* Return pointer to previous entry in ziplist. */
-unsigned char *ziplistPrev(unsigned char *p) {
-    zlentry entry = zipEntry(p);
-    return (entry.prevrawlen == 0) ? NULL : p-entry.prevrawlen;
+unsigned char *ziplistPrev(unsigned char *zl, unsigned char *p) {
+    zlentry entry;
+
+    /* Iterating backwards from ZIP_END should return the tail. When "p" is
+     * equal to the first element of the list, we're already at the head,
+     * and should return NULL. */
+    if (p[0] == ZIP_END) {
+        p = ZIPLIST_ENTRY_TAIL(zl);
+        return (p[0] == ZIP_END) ? NULL : p;
+    } else if (p == ZIPLIST_ENTRY_HEAD(zl)) {
+        return NULL;
+    } else {
+        entry = zipEntry(p);
+        return p-entry.prevrawlen;
+    }
 }
 
 /* Get entry pointer to by 'p' and store in either 'e' or 'v' depending
  * on the encoding of the entry. 'e' is always set to NULL to be able
  * to find out whether the string pointer or the integer value was set.
  * Return 0 if 'p' points to the end of the zipmap, 1 otherwise. */
-unsigned int ziplistGet(unsigned char *p, char **sstr, unsigned int *slen, long long *sval) {
+unsigned int ziplistGet(unsigned char *p, unsigned char **sstr, unsigned int *slen, long long *sval) {
     zlentry entry;
     if (p == NULL || p[0] == ZIP_END) return 0;
     if (sstr) *sstr = NULL;
@@ -451,7 +452,7 @@ unsigned int ziplistGet(unsigned char *p, char **sstr, unsigned int *slen, long
     if (entry.encoding == ZIP_ENC_RAW) {
         if (sstr) {
             *slen = entry.len;
-            *sstr = (char*)p+entry.headersize;
+            *sstr = p+entry.headersize;
         }
     } else {
         if (sval) {
@@ -462,14 +463,14 @@ unsigned int ziplistGet(unsigned char *p, char **sstr, unsigned int *slen, long
 }
 
 /* Insert an entry at "p". */
-unsigned char *ziplistInsert(unsigned char *zl, unsigned char *p, char *s, unsigned int slen) {
+unsigned char *ziplistInsert(unsigned char *zl, unsigned char *p, unsigned char *s, unsigned int slen) {
     return __ziplistInsert(zl,p,s,slen);
 }
 
 /* Delete a single entry from the ziplist, pointed to by *p.
  * Also update *p in place, to be able to iterate over the
  * ziplist, while deleting entries. */
-unsigned char *ziplistDelete(unsigned char *zl, unsigned char **p, int direction) {
+unsigned char *ziplistDelete(unsigned char *zl, unsigned char **p) {
     unsigned int offset = *p-zl;
     zl = __ziplistDelete(zl,*p,1);
 
@@ -477,11 +478,7 @@ unsigned char *ziplistDelete(unsigned char *zl, unsigned char **p, int direction
      * do a realloc which might result in a different "zl"-pointer.
      * When the delete direction is back to front, we might delete the last
      * entry and end up with "p" pointing to ZIP_END, so check this. */
-    if (*(zl+offset) == ZIP_END && direction == ZIPLIST_HEAD) {
-        *p = ZIPLIST_ENTRY_TAIL(zl);
-    } else {
-        *p = zl+offset;
-    }
+    *p = zl+offset;
     return zl;
 }
 
@@ -492,10 +489,10 @@ unsigned char *ziplistDeleteRange(unsigned char *zl, unsigned int index, unsigne
 }
 
 /* Compare entry pointer to by 'p' with 'entry'. Return 1 if equal. */
-unsigned int ziplistCompare(unsigned char *p, char *sstr, unsigned int slen) {
+unsigned int ziplistCompare(unsigned char *p, unsigned char *sstr, unsigned int slen) {
     zlentry entry;
-    char sencoding;
-    long long val, sval;
+    unsigned char sencoding;
+    long long zval, sval;
     if (p[0] == ZIP_END) return 0;
 
     entry = zipEntry(p);
@@ -510,8 +507,8 @@ unsigned int ziplistCompare(unsigned char *p, char *sstr, unsigned int slen) {
         /* Try to compare encoded values */
         if (zipTryEncoding(sstr,&sval,&sencoding)) {
             if (entry.encoding == sencoding) {
-                val = zipLoadInteger(p+entry.headersize,entry.encoding);
-                return val == sval;
+                zval = zipLoadInteger(p+entry.headersize,entry.encoding);
+                return zval == sval;
             }
         }
     }
@@ -521,7 +518,7 @@ unsigned int ziplistCompare(unsigned char *p, char *sstr, unsigned int slen) {
 /* Return length of ziplist. */
 unsigned int ziplistLen(unsigned char *zl) {
     unsigned int len = 0;
-    if (ZIPLIST_LENGTH(zl) < ZIP_BIGLEN) {
+    if (ZIPLIST_LENGTH(zl) < UINT16_MAX) {
         len = ZIPLIST_LENGTH(zl);
     } else {
         unsigned char *p = zl+ZIPLIST_HEADER_SIZE;
@@ -531,7 +528,7 @@ unsigned int ziplistLen(unsigned char *zl) {
         }
 
         /* Re-store length if small enough */
-        if (len < ZIP_BIGLEN) ZIPLIST_LENGTH(zl) = len;
+        if (len < UINT16_MAX) ZIPLIST_LENGTH(zl) = len;
     }
     return len;
 }
@@ -563,13 +560,14 @@ void ziplistRepr(unsigned char *zl) {
 }
 
 #ifdef ZIPLIST_TEST_MAIN
+#include <sys/time.h>
 
 unsigned char *createList() {
     unsigned char *zl = ziplistNew();
-    zl = ziplistPush(zl, "foo", 3, ZIPLIST_TAIL);
-    zl = ziplistPush(zl, "quux", 4, ZIPLIST_TAIL);
-    zl = ziplistPush(zl, "hello", 5, ZIPLIST_HEAD);
-    zl = ziplistPush(zl, "1024", 4, ZIPLIST_TAIL);
+    zl = ziplistPush(zl, (unsigned char*)"foo", 3, ZIPLIST_TAIL);
+    zl = ziplistPush(zl, (unsigned char*)"quux", 4, ZIPLIST_TAIL);
+    zl = ziplistPush(zl, (unsigned char*)"hello", 5, ZIPLIST_HEAD);
+    zl = ziplistPush(zl, (unsigned char*)"1024", 4, ZIPLIST_TAIL);
     return zl;
 }
 
@@ -578,26 +576,79 @@ unsigned char *createIntList() {
     char buf[32];
 
     sprintf(buf, "100");
-    zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_TAIL);
+    zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_TAIL);
     sprintf(buf, "128000");
-    zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_TAIL);
+    zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_TAIL);
     sprintf(buf, "-100");
-    zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_HEAD);
+    zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_HEAD);
     sprintf(buf, "4294967296");
-    zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_HEAD);
+    zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_HEAD);
     sprintf(buf, "non integer");
-    zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_TAIL);
+    zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_TAIL);
     sprintf(buf, "much much longer non integer");
-    zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_TAIL);
+    zl = ziplistPush(zl, (unsigned char*)buf, strlen(buf), ZIPLIST_TAIL);
     return zl;
 }
 
+long long usec(void) {
+    struct timeval tv;
+    gettimeofday(&tv,NULL);
+    return (((long long)tv.tv_sec)*1000000)+tv.tv_usec;
+}
+
+void stress(int pos, int num, int maxsize, int dnum) {
+    int i,j,k;
+    unsigned char *zl;
+    char posstr[2][5] = { "HEAD", "TAIL" };
+    long long start;
+    for (i = 0; i < maxsize; i+=dnum) {
+        zl = ziplistNew();
+        for (j = 0; j < i; j++) {
+            zl = ziplistPush(zl,(unsigned char*)"quux",4,ZIPLIST_TAIL);
+        }
+
+        /* Do num times a push+pop from pos */
+        start = usec();
+        for (k = 0; k < num; k++) {
+            zl = ziplistPush(zl,(unsigned char*)"quux",4,pos);
+            zl = ziplistDeleteRange(zl,0,1);
+        }
+        printf("List size: %8d, bytes: %8d, %dx push+pop (%s): %6lld usec\n",
+            i,ZIPLIST_BYTES(zl),num,posstr[pos],usec()-start);
+        zfree(zl);
+    }
+}
+
+void pop(unsigned char *zl, int where) {
+    unsigned char *p, *vstr;
+    unsigned int vlen;
+    long long vlong;
+
+    p = ziplistIndex(zl,where == ZIPLIST_HEAD ? 0 : -1);
+    if (ziplistGet(p,&vstr,&vlen,&vlong)) {
+        if (where == ZIPLIST_HEAD)
+            printf("Pop head: ");
+        else
+            printf("Pop tail: ");
+
+        if (vstr)
+            fwrite(vstr,vlen,1,stdout);
+        else
+            printf("%lld", vlong);
+
+        printf("\n");
+        ziplistDeleteRange(zl,-1,1);
+    } else {
+        printf("ERROR: Could not pop\n");
+        exit(1);
+    }
+}
+
 int main(int argc, char **argv) {
     unsigned char *zl, *p;
-    char *entry;
+    unsigned char *entry;
     unsigned int elen;
     long long value;
-    sds s;
 
     zl = createIntList();
     ziplistRepr(zl);
@@ -605,20 +656,16 @@ int main(int argc, char **argv) {
     zl = createList();
     ziplistRepr(zl);
 
-    zl = ziplistPop(zl, &s, ZIPLIST_TAIL);
-    printf("Pop tail: %s (length %ld)\n", s, sdslen(s));
+    pop(zl,ZIPLIST_TAIL);
     ziplistRepr(zl);
 
-    zl = ziplistPop(zl, &s, ZIPLIST_HEAD);
-    printf("Pop head: %s (length %ld)\n", s, sdslen(s));
+    pop(zl,ZIPLIST_HEAD);
     ziplistRepr(zl);
 
-    zl = ziplistPop(zl, &s, ZIPLIST_TAIL);
-    printf("Pop tail: %s (length %ld)\n", s, sdslen(s));
+    pop(zl,ZIPLIST_TAIL);
     ziplistRepr(zl);
 
-    zl = ziplistPop(zl, &s, ZIPLIST_TAIL);
-    printf("Pop tail: %s (length %ld)\n", s, sdslen(s));
+    pop(zl,ZIPLIST_TAIL);
     ziplistRepr(zl);
 
     printf("Get element at index 3:\n");
@@ -709,7 +756,7 @@ int main(int argc, char **argv) {
             } else {
                 printf("%lld", value);
             }
-            p = ziplistNext(p);
+            p = ziplistNext(zl,p);
             printf("\n");
         }
         printf("\n");
@@ -726,7 +773,7 @@ int main(int argc, char **argv) {
             } else {
                 printf("%lld", value);
             }
-            p = ziplistNext(p);
+            p = ziplistNext(zl,p);
             printf("\n");
         }
         printf("\n");
@@ -743,7 +790,7 @@ int main(int argc, char **argv) {
             } else {
                 printf("%lld", value);
             }
-            p = ziplistNext(p);
+            p = ziplistNext(zl,p);
             printf("\n");
         }
         printf("\n");
@@ -772,7 +819,7 @@ int main(int argc, char **argv) {
             } else {
                 printf("%lld", value);
             }
-            p = ziplistPrev(p);
+            p = ziplistPrev(zl,p);
             printf("\n");
         }
         printf("\n");
@@ -789,7 +836,8 @@ int main(int argc, char **argv) {
             } else {
                 printf("%lld", value);
             }
-            zl = ziplistDelete(zl, &p, ZIPLIST_HEAD);
+            zl = ziplistDelete(zl,&p);
+            p = ziplistPrev(zl,p);
             printf("\n");
         }
         printf("\n");
@@ -833,19 +881,19 @@ int main(int argc, char **argv) {
     printf("Delete foo while iterating:\n");
     {
         zl = createList();
-        p = ziplistIndex(zl, 0);
-        while (ziplistGet(p, &entry, &elen, &value)) {
-            if (entry && strncmp("foo", entry, elen) == 0) {
+        p = ziplistIndex(zl,0);
+        while (ziplistGet(p,&entry,&elen,&value)) {
+            if (entry && strncmp("foo",(char*)entry,elen) == 0) {
                 printf("Delete foo\n");
-                zl = ziplistDelete(zl, &p, ZIPLIST_TAIL);
+                zl = ziplistDelete(zl,&p);
             } else {
                 printf("Entry: ");
                 if (entry) {
                     fwrite(entry,elen,1,stdout);
                 } else {
-                    printf("%lld", value);
+                    printf("%lld",value);
                 }
-                p = ziplistNext(p);
+                p = ziplistNext(zl,p);
                 printf("\n");
             }
         }
@@ -853,31 +901,59 @@ int main(int argc, char **argv) {
         ziplistRepr(zl);
     }
 
+    printf("Create long list and check indices:\n");
+    {
+        zl = ziplistNew();
+        char buf[32];
+        int i,len;
+        for (i = 0; i < 1000; i++) {
+            len = sprintf(buf,"%d",i);
+            zl = ziplistPush(zl,(unsigned char*)buf,len,ZIPLIST_TAIL);
+        }
+        for (i = 0; i < 1000; i++) {
+            p = ziplistIndex(zl,i);
+            assert(ziplistGet(p,NULL,NULL,&value));
+            assert(i == value);
+
+            p = ziplistIndex(zl,-i-1);
+            assert(ziplistGet(p,NULL,NULL,&value));
+            assert(999-i == value);
+        }
+        printf("SUCCESS\n\n");
+    }
+
     printf("Compare strings with ziplist entries:\n");
     {
         zl = createList();
-        p = ziplistIndex(zl, 0);
-        if (!ziplistCompare(p,"hello",5)) {
+        p = ziplistIndex(zl,0);
+        if (!ziplistCompare(p,(unsigned char*)"hello",5)) {
             printf("ERROR: not \"hello\"\n");
             return 1;
         }
-        if (ziplistCompare(p,"hella",5)) {
+        if (ziplistCompare(p,(unsigned char*)"hella",5)) {
             printf("ERROR: \"hella\"\n");
             return 1;
         }
 
-        p = ziplistIndex(zl, 3);
-        if (!ziplistCompare(p,"1024",4)) {
+        p = ziplistIndex(zl,3);
+        if (!ziplistCompare(p,(unsigned char*)"1024",4)) {
             printf("ERROR: not \"1024\"\n");
             return 1;
         }
-        if (ziplistCompare(p,"1025",4)) {
+        if (ziplistCompare(p,(unsigned char*)"1025",4)) {
             printf("ERROR: \"1025\"\n");
             return 1;
         }
         printf("SUCCESS\n");
     }
 
+    printf("Stress with variable ziplist size:\n");
+    {
+        stress(ZIPLIST_HEAD,100000,16384,256);
+        stress(ZIPLIST_TAIL,100000,16384,256);
+    }
+
     return 0;
 }
+
 #endif