#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <stdint.h>
#include <assert.h>
#include <limits.h>
#include "zmalloc.h"
/* 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 */
#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;
} 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);
}
/* 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;
}
/* 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);
}
}
/* 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);
}
/* 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;
/* When the insert position is not equal to the tail, we need to
* make sure that the next entry can hold this entry's length in
* its prevlen field. */
- nextdiff = p[0] != ZIP_END ? zipPrevLenByteDiff(p,reqlen) : 0;
+ nextdiff = (p[0] != ZIP_END) ? zipPrevLenByteDiff(p,reqlen) : 0;
/* Store offset because a realloc may change the address of zl. */
offset = p-zl;
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);
p += zipRawEntryLength(p);
}
}
- return p[0] == ZIP_END || index > 0 ? NULL : p;
+ return (p[0] == ZIP_END || index > 0) ? NULL : p;
}
/* Return pointer to next entry in ziplist. */
-unsigned char *ziplistNext(unsigned char *p) {
- return *p == ZIP_END ? p : 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 *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;
if (entry.encoding == ZIP_ENC_RAW) {
if (sstr) {
*slen = entry.len;
- *sstr = (char*)p+entry.headersize;
+ *sstr = p+entry.headersize;
}
} else {
if (sval) {
return 1;
}
-/* Delete a range of entries from the ziplist. */
-unsigned char *ziplistDeleteRange(unsigned char *zl, unsigned int index, unsigned int num) {
- unsigned char *p = ziplistIndex(zl,index);
- return p == NULL ? zl : __ziplistDelete(zl,p,num);
+/* Insert an entry at "p". */
+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.
zl = __ziplistDelete(zl,*p,1);
/* Store pointer to current element in p, because ziplistDelete will
- * do a realloc which might result in a different "zl"-pointer. */
+ * 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. */
*p = zl+offset;
return zl;
}
+/* Delete a range of entries from the ziplist. */
+unsigned char *ziplistDeleteRange(unsigned char *zl, unsigned int index, unsigned int num) {
+ unsigned char *p = ziplistIndex(zl,index);
+ return (p == NULL) ? zl : __ziplistDelete(zl,p,num);
+}
+
/* 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;
- if (*p == ZIP_END) return 0;
+ unsigned char sencoding;
+ long long zval, sval;
+ if (p[0] == ZIP_END) return 0;
entry = zipEntry(p);
if (entry.encoding == ZIP_ENC_RAW) {
/* 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;
}
}
}
/* 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;
}
/* Re-store length if small enough */
- if (len < ZIP_BIGLEN) ZIPLIST_LENGTH(zl) = len;
+ if (len < UINT16_MAX) ZIPLIST_LENGTH(zl) = len;
}
return len;
}
}
#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;
}
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);
+ }
+}
+
int main(int argc, char **argv) {
unsigned char *zl, *p;
- char *entry;
+ unsigned char *entry;
unsigned int elen;
long long value;
sds s;
} else {
printf("%lld", value);
}
- p = ziplistNext(p);
+ p = ziplistNext(zl,p);
printf("\n");
}
printf("\n");
} else {
printf("%lld", value);
}
- p = ziplistNext(p);
+ p = ziplistNext(zl,p);
printf("\n");
}
printf("\n");
} else {
printf("%lld", value);
}
- p = ziplistNext(p);
+ p = ziplistNext(zl,p);
printf("\n");
}
printf("\n");
printf("\n");
}
+ printf("Iterate from back to front:\n");
+ {
+ zl = createList();
+ p = ziplistIndex(zl, -1);
+ while (ziplistGet(p, &entry, &elen, &value)) {
+ printf("Entry: ");
+ if (entry) {
+ fwrite(entry,elen,1,stdout);
+ } else {
+ printf("%lld", value);
+ }
+ p = ziplistPrev(zl,p);
+ printf("\n");
+ }
+ printf("\n");
+ }
+
+ printf("Iterate from back to front, deleting all items:\n");
+ {
+ zl = createList();
+ p = ziplistIndex(zl, -1);
+ while (ziplistGet(p, &entry, &elen, &value)) {
+ printf("Entry: ");
+ if (entry) {
+ fwrite(entry,elen,1,stdout);
+ } else {
+ printf("%lld", value);
+ }
+ zl = ziplistDelete(zl,&p);
+ p = ziplistPrev(zl,p);
+ printf("\n");
+ }
+ printf("\n");
+ }
+
printf("Delete inclusive range 0,0:\n");
{
zl = createList();
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);
+ 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");
}
}
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