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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
|
/* Copyright (C) 2000-2002 MySQL AB
Copyright (C) 2008 eBay, Inc
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* Implements various base record-related functions, such as encode and decode into chunks */
#include "heap_priv.h"
#include <drizzled/common.h>
#include <string.h>
#include <algorithm>
using namespace std;
using namespace drizzled;
/**
Calculate size of the record for the purpose of storing in chunks
Walk through the fields of the record and calculates the exact space
needed in chunks as well the the total chunk count
@param info the hosting table
@param record the record in standard unpacked format
@param[out] chunk_count the number of chunks needed for this record
@return The size of the required storage in bytes
*/
uint32_t hp_get_encoded_data_length(HP_SHARE *info, const unsigned char *record, uint32_t *chunk_count)
{
uint32_t i, dst_offset;
dst_offset= info->fixed_data_length;
if (!info->recordspace.is_variable_size)
{
/* Nothing more to copy */
*chunk_count= 1;
return dst_offset;
}
for (i= info->fixed_column_count; i < info->column_count; i++)
{
uint32_t src_offset, length;
HP_COLUMNDEF* column= info->column_defs + i;
if (column->null_bit)
{
if (record[column->null_pos] & column->null_bit)
{
/* Skip all NULL values */
continue;
}
}
src_offset= column->offset;
if (column->type == DRIZZLE_TYPE_VARCHAR)
{
uint32_t pack_length;
/* >= 5.0.3 true VARCHAR */
pack_length= column->length_bytes;
length= pack_length + (pack_length == 1 ?
(uint) *(unsigned char*) (record + src_offset) : uint2korr(record + src_offset));
}
else
{
length= column->length;
}
dst_offset+= length;
}
*chunk_count= get_chunk_count(&info->recordspace, dst_offset);
return dst_offset;
}
/*static void dump_chunk(HP_SHARE *info, const unsigned char* curr_chunk)
{
uint32_t i;
fprintf(stdout, "Chunk dump at 0x%lx: ", (long)curr_chunk);
for (i= 0; i < info->chunk_dataspace_length; i++)
{
uint32_t b= *((unsigned char*)(curr_chunk + i));
if (b < 0x10)
{
fprintf(stdout, "0");
}
fprintf(stdout, "%lx ", (long)b);
}
fprintf(stdout, ". Next = 0x%lx, Status = %d\n",
(long)(*((unsigned char**) (curr_chunk + info->offset_link))),
(uint)(*((unsigned char*) (curr_chunk + info->offset_status))));
}*/
/**
Encodes or compares record
Copies data from original unpacked record into the preallocated chunkset,
or performs data comparison
@param info the hosting table
@param record the record in standard unpacked format
@param pos the target chunkset
@param is_compare flag indicating whether we should compare data or store it
@return Status of comparison
@retval non-zero if comparison fond data differences
@retval zero otherwise
*/
uint32_t hp_process_record_data_to_chunkset(HP_SHARE *info, const unsigned char *record,
unsigned char *pos, uint32_t is_compare)
{
uint32_t i, dst_offset;
unsigned char* curr_chunk= pos;
if (is_compare)
{
if (memcmp(curr_chunk, record, (size_t) info->fixed_data_length))
{
return 1;
}
}
else
{
memcpy(curr_chunk, record, (size_t) info->fixed_data_length);
}
if (!info->recordspace.is_variable_size)
{
/* Nothing more to copy */
return 0;
}
dst_offset= info->fixed_data_length;
for (i= info->fixed_column_count; i < info->column_count; i++)
{
uint32_t src_offset, length;
HP_COLUMNDEF* column= info->column_defs + i;
if (column->null_bit)
{
if (record[column->null_pos] & column->null_bit)
{
/* Skip all NULL values */
continue;
}
}
src_offset= column->offset;
if (column->type == DRIZZLE_TYPE_VARCHAR)
{
uint32_t pack_length;
/* >= 5.0.3 true VARCHAR */
/* Make sure to copy length indicator and actuals string bytes */
pack_length= column->length_bytes;
length= pack_length + (pack_length == 1 ?
(uint) *(unsigned char*) (record + src_offset) : uint2korr(record + src_offset));
}
else
{
length= column->length;
}
while (length > 0)
{
uint32_t to_copy;
to_copy= info->recordspace.chunk_dataspace_length - dst_offset;
if (to_copy == 0)
{
/* Jump to the next chunk */
/*dump_chunk(info, curr_chunk);*/
curr_chunk= *((unsigned char**) (curr_chunk + info->recordspace.offset_link));
dst_offset= 0;
continue;
}
to_copy= min(length, to_copy);
if (is_compare)
{
if (memcmp(curr_chunk + dst_offset, record + src_offset, (size_t) to_copy))
{
return 1;
}
}
else
{
memcpy(curr_chunk + dst_offset, record + src_offset, (size_t) to_copy);
}
src_offset+= to_copy;
dst_offset+= to_copy;
length-= to_copy;
}
}
/*dump_chunk(info, curr_chunk);*/
return 0;
}
/**
Stores record in the heap table chunks
Copies data from original unpacked record into the preallocated chunkset
@param info the hosting table
@param record the record in standard unpacked format
@param pos the target chunkset
*/
void hp_copy_record_data_to_chunkset(HP_SHARE *info, const unsigned char *record, unsigned char *pos)
{
hp_process_record_data_to_chunkset(info, record, pos, 0);
return;
}
/*
Macro to switch curr_chunk to the next chunk in the chunkset and reset src_offset
*/
#define SWITCH_TO_NEXT_CHUNK_FOR_READ(info, curr_chunk, src_offset) \
{ \
curr_chunk= *((unsigned char**) (curr_chunk + info->recordspace.offset_link)); \
src_offset= 0; \
/*dump_chunk(info, curr_chunk);*/ \
}
/**
Copies record data from storage to unpacked record format
Copies data from chunkset into its original unpacked record
@param info the hosting table
@param[out] record the target record in standard unpacked format
@param pos the source chunkset
*/
void hp_extract_record(HP_SHARE *info, unsigned char *record, const unsigned char *pos)
{
uint32_t i, src_offset;
const unsigned char* curr_chunk= pos;
/*if (info->is_variable_size)
{
dump_chunk(info, curr_chunk);
}*/
memcpy(record, curr_chunk, (size_t) info->fixed_data_length);
if (!info->recordspace.is_variable_size)
{
/* Nothing more to copy */
return;
}
src_offset= info->fixed_data_length;
for (i= info->fixed_column_count; i < info->column_count; i++)
{
uint32_t dst_offset, length, is_null = 0;
HP_COLUMNDEF* column= info->column_defs + i;
if (column->null_bit)
{
if (record[column->null_pos] & column->null_bit)
{
is_null = 1;
}
}
dst_offset= column->offset;
if (column->type == DRIZZLE_TYPE_VARCHAR)
{
uint32_t pack_length, byte1, byte2;
/* >= 5.0.3 true VARCHAR */
if (is_null)
{
/* TODO: is memset really needed? */
memset(record + column->offset, 0, column->length);
continue;
}
pack_length= column->length_bytes;
if (src_offset == info->recordspace.chunk_dataspace_length)
{
SWITCH_TO_NEXT_CHUNK_FOR_READ(info, curr_chunk, src_offset);
}
byte1= *(unsigned char*) (curr_chunk + src_offset++);
*(record + dst_offset++)= byte1;
if (pack_length == 1)
{
length= byte1;
}
else
{
if (src_offset == info->recordspace.chunk_dataspace_length)
{
SWITCH_TO_NEXT_CHUNK_FOR_READ(info, curr_chunk, src_offset);
}
byte2= *(unsigned char*) (curr_chunk + src_offset++);
*(record + dst_offset++)= byte2;
/* We copy byte-by-byte and then use uint2korr to combine bytes in the right order */
length= uint2korr(record + dst_offset - 2);
}
}
else
{
if (is_null)
{
/* TODO: is memset really needed? */
memset(record + column->offset, 0, column->length);
continue;
}
length= column->length;
}
while (length > 0)
{
uint32_t to_copy;
to_copy= info->recordspace.chunk_dataspace_length - src_offset;
if (to_copy == 0)
{
SWITCH_TO_NEXT_CHUNK_FOR_READ(info, curr_chunk, src_offset);
to_copy= info->recordspace.chunk_dataspace_length;
}
to_copy= min(length, to_copy);
memcpy(record + dst_offset, curr_chunk + src_offset, (size_t) to_copy);
src_offset+= to_copy;
dst_offset+= to_copy;
length-= to_copy;
}
}
return;
}
|