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+/*****************************************************************************
+
+Copyright (c) 2007, 2011, Oracle and/or its affiliates. All Rights Reserved.
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; version 2 of the License.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA
+
+*****************************************************************************/
+
+/******************************************************************//**
+@file include/fts0vlc.ic
+Full text variable length integer encoding/decoding.
+
+Created 2007-03-27 Sunny Bains
+*******************************************************/
+
+#ifndef INNOBASE_FTS0VLC_IC
+#define INNOBASE_FTS0VLC_IC
+
+#include "fts0types.h"
+
+/******************************************************************//**
+Return length of val if it were encoded using our VLC scheme.
+FIXME: We will need to be able encode 8 bytes value
+@return length of value encoded, in bytes */
+UNIV_INLINE
+ulint
+fts_get_encoded_len(
+/*================*/
+ ulint val) /* in: value to encode */
+{
+ if (val <= 127) {
+ return(1);
+ } else if (val <= 16383) {
+ return(2);
+ } else if (val <= 2097151) {
+ return(3);
+ } else if (val <= 268435455) {
+ return(4);
+ } else {
+ /* Possibly we should care that on 64-bit machines ulint can
+ contain values that we can't encode in 5 bytes, but
+ fts_encode_int doesn't handle them either so it doesn't much
+ matter. */
+
+ return(5);
+ }
+}
+
+/******************************************************************//**
+Encode an integer using our VLC scheme and return the length in bytes.
+@return length of value encoded, in bytes */
+UNIV_INLINE
+ulint
+fts_encode_int(
+/*===========*/
+ ulint val, /* in: value to encode */
+ byte* buf) /* in: buffer, must have enough space */
+{
+ ulint len;
+
+ if (val <= 127) {
+ *buf = (byte) val;
+
+ len = 1;
+ } else if (val <= 16383) {
+ *buf++ = (byte)(val >> 7);
+ *buf = (byte)(val & 0x7F);
+
+ len = 2;
+ } else if (val <= 2097151) {
+ *buf++ = (byte)(val >> 14);
+ *buf++ = (byte)((val >> 7) & 0x7F);
+ *buf = (byte)(val & 0x7F);
+
+ len = 3;
+ } else if (val <= 268435455) {
+ *buf++ = (byte)(val >> 21);
+ *buf++ = (byte)((val >> 14) & 0x7F);
+ *buf++ = (byte)((val >> 7) & 0x7F);
+ *buf = (byte)(val & 0x7F);
+
+ len = 4;
+ } else {
+ /* Best to keep the limitations of the 32/64 bit versions
+ identical, at least for the time being. */
+ ut_ad(val <= 4294967295u);
+
+ *buf++ = (byte)(val >> 28);
+ *buf++ = (byte)((val >> 21) & 0x7F);
+ *buf++ = (byte)((val >> 14) & 0x7F);
+ *buf++ = (byte)((val >> 7) & 0x7F);
+ *buf = (byte)(val & 0x7F);
+
+ len = 5;
+ }
+
+ /* High-bit on means "last byte in the encoded integer". */
+ *buf |= 0x80;
+
+ return(len);
+}
+
+/******************************************************************//**
+Decode and return the integer that was encoded using our VLC scheme.
+@return value decoded */
+UNIV_INLINE
+ulint
+fts_decode_vlc(
+/*===========*/
+ byte** ptr) /* in: ptr to decode from, this ptr is
+ incremented by the number of bytes decoded */
+{
+ ulint val = 0;
+
+ for (;;) {
+ byte b = **ptr;
+
+ ++*ptr;
+ val |= (b & 0x7F);
+
+ /* High-bit on means "last byte in the encoded integer". */
+ if (b & 0x80) {
+ break;
+ } else {
+ val <<= 7;
+ }
+ }
+
+ return(val);
+}
+
+#endif