+int iscz1_decode_int (unsigned char **src)
+{
+ unsigned c = *(*src)++;
+ switch (c & 192)
+ {
+ case 0:
+ return c;
+ case 64:
+ return ((c & 63) << 8) + *(*src)++;
+ case 128:
+ c = ((c & 63) << 8) + *(*src)++;
+ c = (c << 8) + *(*src)++;
+ return c;
+ }
+ c = ((c & 63) << 8) + *(*src)++;
+ c = (c << 8) + *(*src)++;
+ c = (c << 8) + *(*src)++;
+ return c;
+}
+#if 1
+static void iscz1_code_item (int mode, void *vp, char **dst, char **src)
+{
+ struct iscz1_code_info *p = vp;
+ struct it_key tkey;
+ int d;
+
+ if (mode == ISAMC_ENCODE)
+ {
+ memcpy (&tkey, *src, sizeof(struct it_key));
+ d = tkey.sysno - p->key.sysno;
+ if (d)
+ {
+ iscz1_encode_int (2*tkey.seqno + 1, dst);
+ iscz1_encode_int (d, dst);
+ p->key.sysno += d;
+ p->key.seqno = tkey.seqno;
+ }
+ else
+ {
+ iscz1_encode_int (2*(tkey.seqno - p->key.seqno), dst);
+ p->key.seqno = tkey.seqno;
+ }
+ (*src) += sizeof(struct it_key);
+ }
+ else
+ {
+ d = iscz1_decode_int ((unsigned char **) src);
+ if (d & 1)
+ {
+ p->key.seqno = d>>1;
+ p->key.sysno += iscz1_decode_int ((unsigned char **) src);
+ }
+ else
+ p->key.seqno += d>>1;
+ memcpy (*dst, &p->key, sizeof(struct it_key));
+ (*dst) += sizeof(struct it_key);
+ }
+}
+#else
+static void iscz1_code_item (int mode, void *vp, char **dst, char **src)