#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
/* 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) (*((unsigned int*)((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;
/* Return bytes needed to store integer encoded by 'encoding' */
static unsigned int zipEncodingSize(unsigned 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);
+ 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);
}
if (entry[0] == '-' || (entry[0] >= '0' && entry[0] <= '9')) {
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, unsigned 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, unsigned 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);
}
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. */
/* 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;
}
}
}
+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;
unsigned char *entry;
unsigned int elen;
long long value;
- sds s;
zl = createIntList();
ziplistRepr(zl);
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");
projects / redis.git / blobdiff