*/
#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
#include <assert.h>
+#include <limits.h>
#include "zmalloc.h"
#include "sds.h"
#include "ziplist.h"
-#include "zip.c"
+#define ZIP_END 255
+#define ZIP_BIGLEN 254
+
+/* Entry encoding */
+#define ZIP_ENC_RAW 0
+#define ZIP_ENC_SHORT 1
+#define ZIP_ENC_INT 2
+#define ZIP_ENC_LLONG 3
+#define ZIP_ENCODING(p) ((p)[0] >> 6)
+
+/* Length encoding for raw entries */
+#define ZIP_LEN_INLINE 0
+#define ZIP_LEN_UINT16 1
+#define ZIP_LEN_UINT32 2
+
+/* Utility macros */
#define ZIPLIST_BYTES(zl) (*((unsigned int*)(zl)))
#define ZIPLIST_LENGTH(zl) (*((zl)+sizeof(unsigned int)))
#define ZIPLIST_HEADER_SIZE (sizeof(unsigned int)+1)
+#define ZIPLIST_INCR_LENGTH(zl,incr) { \
+ if (ZIPLIST_LENGTH(zl) < ZIP_BIGLEN) ZIPLIST_LENGTH(zl)+=incr; }
+
+/* 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);
+ }
+ assert(NULL);
+}
+
+/* Decode the encoded length pointed by 'p'. If a pointer to 'lensize' is
+ * provided, it is set to the number of bytes required to encode the length. */
+static unsigned int zipDecodeLength(unsigned char *p, unsigned int *lensize) {
+ unsigned char encoding = ZIP_ENCODING(p), lenenc;
+ unsigned int len;
+
+ if (encoding == ZIP_ENC_RAW) {
+ lenenc = (p[0] >> 4) & 0x3;
+ if (lenenc == ZIP_LEN_INLINE) {
+ len = p[0] & 0xf;
+ if (lensize) *lensize = 1;
+ } else if (lenenc == ZIP_LEN_UINT16) {
+ len = p[1] | (p[2] << 8);
+ if (lensize) *lensize = 3;
+ } else {
+ len = p[1] | (p[2] << 8) | (p[3] << 16) | (p[4] << 24);
+ if (lensize) *lensize = 5;
+ }
+ } else {
+ len = zipEncodingSize(encoding);
+ if (lensize) *lensize = 1;
+ }
+ return len;
+}
+
+/* Encode the length 'l' writing it in 'p'. If p is NULL it just returns
+ * the amount of bytes required to encode such a length. */
+static unsigned int zipEncodeLength(unsigned char *p, char encoding, unsigned int rawlen) {
+ unsigned char len = 1, lenenc, buf[5];
+ if (encoding == ZIP_ENC_RAW) {
+ if (rawlen <= 0xf) {
+ if (!p) return len;
+ lenenc = ZIP_LEN_INLINE;
+ buf[0] = rawlen;
+ } else if (rawlen <= 0xffff) {
+ len += 2;
+ if (!p) return len;
+ lenenc = ZIP_LEN_UINT16;
+ buf[1] = (rawlen ) & 0xff;
+ buf[2] = (rawlen >> 8) & 0xff;
+ } else {
+ len += 4;
+ if (!p) return len;
+ lenenc = ZIP_LEN_UINT32;
+ buf[1] = (rawlen ) & 0xff;
+ buf[2] = (rawlen >> 8) & 0xff;
+ buf[3] = (rawlen >> 16) & 0xff;
+ buf[4] = (rawlen >> 24) & 0xff;
+ }
+ buf[0] = (lenenc << 4) | (buf[0] & 0xf);
+ }
+ if (!p) return len;
+
+ /* Apparently we need to store the length in 'p' */
+ buf[0] = (encoding << 6) | (buf[0] & 0x3f);
+ memcpy(p,buf,len);
+ return 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(unsigned char *entry, long long *v, char *encoding) {
+ long long value;
+ char *eptr;
+
+ if (entry[0] == '-' || (entry[0] >= '0' && entry[0] <= '9')) {
+ value = strtoll(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;
+ } else {
+ *encoding = ZIP_ENC_LLONG;
+ }
+ *v = value;
+ return 1;
+ }
+ return 0;
+}
+
+/* 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));
+ } 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;
+ } else {
+ assert(NULL);
+ }
+ return ret;
+}
+
+/* Return the total amount used by an entry (encoded length + payload). */
+static unsigned int zipRawEntryLength(unsigned char *p) {
+ unsigned int lensize, len;
+ len = zipDecodeLength(p, &lensize);
+ return lensize + len;
+}
/* Create a new empty ziplist. */
unsigned char *ziplistNew(void) {
return zl;
}
+/* Resize the ziplist. */
static unsigned char *ziplistResize(unsigned char *zl, unsigned int len) {
- zl = zipResize(zl,len);
+ zl = zrealloc(zl,len);
ZIPLIST_BYTES(zl) = len;
zl[len-1] = ZIP_END;
return zl;
}
unsigned char *ziplistPush(unsigned char *zl, unsigned char *entry, unsigned int elen, int where) {
- unsigned int curlen = ZIPLIST_BYTES(zl);
- unsigned int reqlen = zipEncodeLength(NULL,elen)+elen;
+ unsigned int curlen = ZIPLIST_BYTES(zl), reqlen;
unsigned char *p;
+ char encoding = ZIP_ENC_RAW;
+ long long value;
- /* Resize the ziplist */
- zl = ziplistResize(zl,curlen+reqlen);
+ /* See if the entry can be encoded */
+ if (zipTryEncoding(entry,&value,&encoding)) {
+ reqlen = zipEncodingSize(encoding);
+ } else {
+ reqlen = elen;
+ }
+ reqlen += zipEncodeLength(NULL,encoding,elen);
+ /* Resize the ziplist and move if needed */
+ zl = ziplistResize(zl,curlen+reqlen);
if (where == ZIPLIST_HEAD) {
p = zl+ZIPLIST_HEADER_SIZE;
if (*p != ZIP_END) {
p = zl+curlen-1;
}
- /* Increase length */
- if (ZIPLIST_LENGTH(zl) < ZIP_BIGLEN) ZIPLIST_LENGTH(zl)++;
-
/* Write the entry */
- p += zipEncodeLength(p,elen);
- memcpy(p,entry,elen);
+ p += zipEncodeLength(p,encoding,elen);
+ if (encoding != ZIP_ENC_RAW) {
+ zipSaveInteger(p,value,encoding);
+ } else {
+ memcpy(p,entry,elen);
+ }
+ ZIPLIST_INCR_LENGTH(zl,1);
return zl;
}
-unsigned char *ziplistPop(unsigned char *zl, sds *value, int where) {
- unsigned int curlen = ZIPLIST_BYTES(zl), len, rlen;
+unsigned char *ziplistPop(unsigned char *zl, sds *target, int where) {
+ unsigned int curlen = ZIPLIST_BYTES(zl), rawlen;
+ unsigned int len, lensize;
unsigned char *p;
- if (value) *value = NULL;
+ long long value;
+ if (target) *target = NULL;
/* Get pointer to element to remove */
p = (where == ZIPLIST_HEAD) ? ziplistHead(zl) : ziplistTail(zl);
if (*p == ZIP_END) return zl;
- len = zipDecodeLength(p);
- if (value) *value = sdsnewlen(p+zipEncodeLength(NULL,len),len);
+ len = zipDecodeLength(p,&lensize);
+ if (target) {
+ if (ZIP_ENCODING(p) == ZIP_ENC_RAW) {
+ *target = sdsnewlen(p+lensize,len);
+ } else {
+ value = zipLoadInteger(p+lensize,ZIP_ENCODING(p));
+ *target = sdscatprintf(sdsempty(), "%lld", value);
+ }
+ }
/* Move list to front when popping from the head */
- rlen = zipRawEntryLength(p);
+ rawlen = lensize+len;
if (where == ZIPLIST_HEAD) {
- memmove(p,p+rlen,curlen-ZIPLIST_HEADER_SIZE-len);
+ memmove(p,p+rawlen,curlen-ZIPLIST_HEADER_SIZE-len);
}
/* Resize and update length */
- zl = ziplistResize(zl,curlen-rlen);
- if (ZIPLIST_LENGTH(zl) < ZIP_BIGLEN) ZIPLIST_LENGTH(zl)--;
+ zl = ziplistResize(zl,curlen-rawlen);
+ ZIPLIST_INCR_LENGTH(zl,-1);
return zl;
}
return p;
}
-/* Store entry at current position in sds *value and return pointer
- * to the next entry. */
-unsigned char *ziplistNext(unsigned char *p, unsigned char **entry, unsigned int *elen) {
- if (*p == ZIP_END) return NULL;
- if (entry) {
- *elen = zipDecodeLength(p);
- *entry = p+ZIP_LEN_BYTES(*elen);
+/* Return pointer to next entry in ziplist. */
+unsigned char *ziplistNext(unsigned char *p) {
+ return *p == ZIP_END ? p : p+zipRawEntryLength(p);
+}
+
+/* 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, unsigned char **e, unsigned int *elen, long long *v) {
+ unsigned int len, lensize;
+ if (*p == ZIP_END) return 0;
+ if (e) *e = NULL;
+ len = zipDecodeLength(p,&lensize);
+ if (ZIP_ENCODING(p) == ZIP_ENC_RAW) {
+ if (e) {
+ *elen = len;
+ *e = p+lensize;
+ }
+ } else {
+ if (v) {
+ *v = zipLoadInteger(p+lensize,ZIP_ENCODING(p));
+ }
}
- p += zipRawEntryLength(p);
- return p;
+ return 1;
}
-/* Delete one or more entries from the ziplist. */
-unsigned char *ziplistDelete(unsigned char *zl, unsigned int index, unsigned int num) {
+/* Delete a range of entries from the ziplist. */
+unsigned char *ziplistDeleteRange(unsigned char *zl, unsigned int index, unsigned int num) {
unsigned char *p, *first = ziplistIndex(zl, index);
unsigned int i, deleted = 0, totlen, newlen;
for (p = first, i = 0; *p != ZIP_END && i < num; i++) {
/* Resize and update length */
zl = ziplistResize(zl, ZIPLIST_BYTES(zl)-totlen);
- if (ZIPLIST_LENGTH(zl) < ZIP_BIGLEN) ZIPLIST_LENGTH(zl) -= deleted;
+ ZIPLIST_INCR_LENGTH(zl,-deleted);
}
return zl;
}
+/* 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) {
+ unsigned int offset = *p-zl, tail, len;
+ len = zipRawEntryLength(*p);
+ tail = ZIPLIST_BYTES(zl)-offset-len-1;
+
+ /* Move current tail to the new tail when there *is* a tail */
+ if (tail > 0) memmove(*p,*p+len,tail);
+
+ /* Resize and update length */
+ zl = ziplistResize(zl, ZIPLIST_BYTES(zl)-len);
+ ZIPLIST_INCR_LENGTH(zl,-1);
+
+ /* Store new pointer to current element in p.
+ * This needs to be done because zl can change on realloc. */
+ *p = zl+offset;
+ return zl;
+}
+
+/* Compare entry pointer to by 'p' with 'entry'. Return 1 if equal. */
+unsigned int ziplistCompare(unsigned char *p, unsigned char *entry, unsigned int elen) {
+ unsigned int zlen, lensize;
+ char encoding;
+ long long zval, eval;
+ if (*p == ZIP_END) return 0;
+
+ zlen = zipDecodeLength(p,&lensize);
+ if (zipTryEncoding(entry,&eval,&encoding)) {
+ /* Do integer compare */
+ zval = zipLoadInteger(p+lensize,ZIP_ENCODING(p));
+ return zval == eval;
+ } else {
+ /* Raw compare */
+ if (zlen == elen) {
+ return memcmp(p+lensize,entry,elen) == 0;
+ } else {
+ return 0;
+ }
+ }
+}
+
+/* Return length of ziplist. */
+unsigned int ziplistLen(unsigned char *zl) {
+ unsigned int len = 0;
+ if (ZIPLIST_LENGTH(zl) < ZIP_BIGLEN) {
+ len = ZIPLIST_LENGTH(zl);
+ } else {
+ unsigned char *p = zl+ZIPLIST_HEADER_SIZE;
+ while (*p != ZIP_END) {
+ p += zipRawEntryLength(p);
+ len++;
+ }
+
+ /* Re-store length if small enough */
+ if (len < ZIP_BIGLEN) ZIPLIST_LENGTH(zl) = len;
+ }
+ return len;
+}
+
void ziplistRepr(unsigned char *zl) {
- unsigned char *p;
- unsigned int l;
+ unsigned char *p, encoding;
+ unsigned int l, lsize;
+ long long value;
- printf("{bytes %d} {length %u}\n",ZIPLIST_BYTES(zl), ZIPLIST_LENGTH(zl));
+ printf("{total bytes %d} {length %u}\n",ZIPLIST_BYTES(zl), ZIPLIST_LENGTH(zl));
p = ziplistHead(zl);
while(*p != ZIP_END) {
- l = zipDecodeLength(p);
- printf("{key %u}",l);
- p += zipEncodeLength(NULL,l);
- fwrite(p,l,1,stdout);
+ l = zipDecodeLength(p,&lsize);
+ printf("{header %u, payload %u} ",lsize,l);
+ encoding = ZIP_ENCODING(p);
+ p += lsize;
+ if (encoding == ZIP_ENC_RAW) {
+ fwrite(p,l,1,stdout);
+ } else {
+ printf("%lld", zipLoadInteger(p,encoding));
+ }
printf("\n");
p += l;
}
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;
+}
+
+unsigned char *createIntList() {
+ unsigned char *zl = ziplistNew();
+ char buf[32];
+
+ sprintf(buf, "100");
+ zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_TAIL);
+ sprintf(buf, "128000");
+ zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_TAIL);
+ sprintf(buf, "-100");
+ zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_HEAD);
+ sprintf(buf, "4294967296");
+ zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_HEAD);
+ sprintf(buf, "non integer");
+ zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_TAIL);
+ sprintf(buf, "much much longer non integer");
+ zl = ziplistPush(zl, buf, strlen(buf), ZIPLIST_TAIL);
return zl;
}
int main(int argc, char **argv) {
- unsigned char *zl, *p, *entry;
+ unsigned char *zl, *p, *q, *entry;
unsigned int elen;
+ long long value;
sds s;
+ zl = createIntList();
+ ziplistRepr(zl);
+
zl = createList();
ziplistRepr(zl);
{
zl = createList();
p = ziplistIndex(zl, 0);
- while ((p = ziplistNext(p, &entry, &elen)) != NULL) {
+ while (ziplistGet(p, &entry, &elen, &value)) {
printf("Entry: ");
- fwrite(entry,elen,1,stdout);
- printf(" (length %d)\n", elen);
+ if (entry) {
+ fwrite(entry,elen,1,stdout);
+ } else {
+ printf("%lld", value);
+ }
+ p = ziplistNext(p);
+ printf("\n");
}
printf("\n");
}
{
zl = createList();
p = ziplistIndex(zl, 1);
- while ((p = ziplistNext(p, &entry, &elen)) != NULL) {
+ while (ziplistGet(p, &entry, &elen, &value)) {
printf("Entry: ");
- fwrite(entry,elen,1,stdout);
- printf(" (length %d)\n", elen);
+ if (entry) {
+ fwrite(entry,elen,1,stdout);
+ } else {
+ printf("%lld", value);
+ }
+ p = ziplistNext(p);
+ printf("\n");
}
printf("\n");
}
{
zl = createList();
p = ziplistIndex(zl, 2);
- while ((p = ziplistNext(p, &entry, &elen)) != NULL) {
+ while (ziplistGet(p, &entry, &elen, &value)) {
printf("Entry: ");
- fwrite(entry,elen,1,stdout);
- printf(" (length %d)\n", elen);
+ if (entry) {
+ fwrite(entry,elen,1,stdout);
+ } else {
+ printf("%lld", value);
+ }
+ p = ziplistNext(p);
+ printf("\n");
}
printf("\n");
}
printf("Iterate starting out of range:\n");
{
zl = createList();
- p = ziplistIndex(zl, 3);
- if (ziplistNext(p, &entry, &elen) == NULL) {
+ p = ziplistIndex(zl, 4);
+ if (!ziplistGet(p, &entry, &elen, &value)) {
printf("No entry\n");
} else {
printf("ERROR\n");
printf("Delete inclusive range 0,0:\n");
{
zl = createList();
- zl = ziplistDelete(zl, 0, 1);
+ zl = ziplistDeleteRange(zl, 0, 1);
ziplistRepr(zl);
}
printf("Delete inclusive range 0,1:\n");
{
zl = createList();
- zl = ziplistDelete(zl, 0, 2);
+ zl = ziplistDeleteRange(zl, 0, 2);
ziplistRepr(zl);
}
printf("Delete inclusive range 1,2:\n");
{
zl = createList();
- zl = ziplistDelete(zl, 1, 2);
+ zl = ziplistDeleteRange(zl, 1, 2);
ziplistRepr(zl);
}
printf("Delete with start index out of range:\n");
{
zl = createList();
- zl = ziplistDelete(zl, 5, 1);
+ zl = ziplistDeleteRange(zl, 5, 1);
ziplistRepr(zl);
}
printf("Delete with num overflow:\n");
{
zl = createList();
- zl = ziplistDelete(zl, 1, 5);
+ zl = ziplistDeleteRange(zl, 1, 5);
ziplistRepr(zl);
}
+ 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) {
+ printf("Delete foo\n");
+ zl = ziplistDelete(zl, &p);
+ } else {
+ printf("Entry: ");
+ if (entry) {
+ fwrite(entry,elen,1,stdout);
+ } else {
+ printf("%lld", value);
+ }
+ p = ziplistNext(p);
+ printf("\n");
+ }
+ }
+ printf("\n");
+ ziplistRepr(zl);
+ }
+
+ printf("Compare strings with ziplist entries:\n");
+ {
+ zl = createList();
+ p = ziplistIndex(zl, 0);
+ if (!ziplistCompare(p,"hello",5)) {
+ printf("ERROR\n");
+ return;
+ }
+ if (ziplistCompare(p,"hella",5)) {
+ printf("ERROR\n");
+ return;
+ }
+
+ p = ziplistIndex(zl, 3);
+ if (!ziplistCompare(p,"1024",4)) {
+ printf("ERROR\n");
+ return;
+ }
+ if (ziplistCompare(p,"1025",4)) {
+ printf("ERROR\n");
+ return;
+ }
+ printf("SUCCESS\n");
+ }
+
return 0;
}
#endif
projects / redis.git / blobdiff