1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134
|
/*****************************************************************************
Copyright (c) 1995, 2009, Innobase Oy. 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 St, Fifth Floor, Boston, MA 02110-1301 USA
*****************************************************************************/
/******************************************************************//**
@file mach/mach0data.c
Utilities for converting data from the database file
to the machine format.
Created 11/28/1995 Heikki Tuuri
***********************************************************************/
#include "mach0data.h"
#ifdef UNIV_NONINL
#include "mach0data.ic"
#endif
/*********************************************************//**
Reads a ulint in a compressed form if the log record fully contains it.
@return pointer to end of the stored field, NULL if not complete */
UNIV_INTERN
byte*
mach_parse_compressed(
/*==================*/
byte* ptr, /*!< in: pointer to buffer from where to read */
byte* end_ptr,/*!< in: pointer to end of the buffer */
ulint* val) /*!< out: read value (< 2^32) */
{
ulint flag;
ut_ad(ptr && end_ptr && val);
if (ptr >= end_ptr) {
return(NULL);
}
flag = mach_read_from_1(ptr);
if (flag < 0x80UL) {
*val = flag;
return(ptr + 1);
} else if (flag < 0xC0UL) {
if (end_ptr < ptr + 2) {
return(NULL);
}
*val = mach_read_from_2(ptr) & 0x7FFFUL;
return(ptr + 2);
} else if (flag < 0xE0UL) {
if (end_ptr < ptr + 3) {
return(NULL);
}
*val = mach_read_from_3(ptr) & 0x3FFFFFUL;
return(ptr + 3);
} else if (flag < 0xF0UL) {
if (end_ptr < ptr + 4) {
return(NULL);
}
*val = mach_read_from_4(ptr) & 0x1FFFFFFFUL;
return(ptr + 4);
} else {
ut_ad(flag == 0xF0UL);
if (end_ptr < ptr + 5) {
return(NULL);
}
*val = mach_read_from_4(ptr + 1);
return(ptr + 5);
}
}
/*********************************************************//**
Reads a dulint in a compressed form if the log record fully contains it.
@return pointer to end of the stored field, NULL if not complete */
UNIV_INTERN
byte*
mach_dulint_parse_compressed(
/*=========================*/
byte* ptr, /*!< in: pointer to buffer from where to read */
byte* end_ptr,/*!< in: pointer to end of the buffer */
dulint* val) /*!< out: read value */
{
ulint high;
ulint low;
ulint size;
ut_ad(ptr && end_ptr && val);
if (end_ptr < ptr + 5) {
return(NULL);
}
high = mach_read_compressed(ptr);
size = mach_get_compressed_size(high);
ptr += size;
if (end_ptr < ptr + 4) {
return(NULL);
}
low = mach_read_from_4(ptr);
*val = ut_dulint_create(high, low);
return(ptr + 4);
}
|