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
|
/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2004, 2015 Oracle and/or its affiliates. All rights reserved.
*/
#include "gettingstarted_common.h"
int get_item_name(DB *, const DBT *, const DBT *, DBT *);
/*
* Used to extract an inventory item's name from an
* inventory database record. This function is used to create
* keys for secondary database records.
*/
int
get_item_name(DB *dbp, const DBT *pkey, const DBT *pdata, DBT *skey)
{
u_int offset;
dbp = NULL; /* Not needed, unused. */
pkey = NULL;
/*
* First, obtain the buffer location where we placed the
* item's name. In this example, the item's name is located
* in the primary data. It is the first string in the
* buffer after the price (a float) and the quantity (an int).
*
* See load_inventory_database() in example_database_load.c
* for how we packed the inventory information into the
* data DBT.
*/
offset = sizeof(float) + sizeof(int);
/* Check to make sure there's data */
if (pdata->size < offset)
return (-1); /* Returning non-zero means that the
* secondary record is not created/updated.
*/
/* Now set the secondary key's data to be the item name */
memset(skey, 0, sizeof(DBT));
skey->data = (u_int8_t *)pdata->data + offset;
skey->size = (u_int32_t)strlen(skey->data) + 1;
return (0);
}
/* Opens a database */
int
open_database(DB **dbpp, /* The DB handle that we are opening */
const char *file_name, /* The file in which the db lives */
const char *program_name, /* Name of the program */
FILE *error_file_pointer,
int is_secondary)
{
DB *dbp; /* For convenience */
u_int32_t open_flags;
int ret;
/* Initialize the DB handle */
ret = db_create(&dbp, NULL, 0);
if (ret != 0) {
fprintf(error_file_pointer, "%s: %s\n", program_name,
db_strerror(ret));
return (ret);
}
/* Point to the memory malloc'd by db_create() */
*dbpp = dbp;
/* Set up error handling for this database */
dbp->set_errfile(dbp, error_file_pointer);
dbp->set_errpfx(dbp, program_name);
/*
* If this is a secondary database, then we want to allow
* sorted duplicates.
*/
if (is_secondary) {
ret = dbp->set_flags(dbp, DB_DUPSORT);
if (ret != 0) {
dbp->err(dbp, ret, "Attempt to set DUPSORT flags failed.",
file_name);
return (ret);
}
}
/* Set the open flags */
open_flags = DB_CREATE; /* Allow database creation */
/* Now open the database */
ret = dbp->open(dbp, /* Pointer to the database */
NULL, /* Txn pointer */
file_name, /* File name */
NULL, /* Logical db name */
DB_BTREE, /* Database type (using btree) */
open_flags, /* Open flags */
0); /* File mode. Using defaults */
if (ret != 0) {
dbp->err(dbp, ret, "Database '%s' open failed.", file_name);
return (ret);
}
return (0);
}
/* opens all databases */
int
databases_setup(STOCK_DBS *my_stock, const char *program_name,
FILE *error_file_pointer)
{
int ret;
/* Open the vendor database */
ret = open_database(&(my_stock->vendor_dbp),
my_stock->vendor_db_name,
program_name, error_file_pointer,
PRIMARY_DB);
if (ret != 0)
/*
* Error reporting is handled in open_database() so just return
* the return code.
*/
return (ret);
/* Open the inventory database */
ret = open_database(&(my_stock->inventory_dbp),
my_stock->inventory_db_name,
program_name, error_file_pointer,
PRIMARY_DB);
if (ret != 0)
/*
* Error reporting is handled in open_database() so just return
* the return code.
*/
return (ret);
/*
* Open the itemname secondary database. This is used to
* index the product names found in the inventory
* database.
*/
ret = open_database(&(my_stock->itemname_sdbp),
my_stock->itemname_db_name,
program_name, error_file_pointer,
SECONDARY_DB);
if (ret != 0)
/*
* Error reporting is handled in open_database() so just return
* the return code.
*/
return (ret);
/*
* Associate the itemname db with its primary db
* (inventory db).
*/
my_stock->inventory_dbp->associate(
my_stock->inventory_dbp, /* Primary db */
NULL, /* txn id */
my_stock->itemname_sdbp, /* Secondary db */
get_item_name, /* Secondary key creator */
0); /* Flags */
printf("databases opened successfully\n");
return (0);
}
/* Initializes the STOCK_DBS struct.*/
void
initialize_stockdbs(STOCK_DBS *my_stock)
{
my_stock->db_home_dir = DEFAULT_HOMEDIR;
my_stock->inventory_dbp = NULL;
my_stock->vendor_dbp = NULL;
my_stock->itemname_sdbp = NULL;
my_stock->inventory_db_name = NULL;
my_stock->vendor_db_name = NULL;
my_stock->itemname_db_name = NULL;
}
/* Identify all the files that will hold our databases. */
void
set_db_filenames(STOCK_DBS *my_stock)
{
size_t size;
/* Create the Inventory DB file name */
size = strlen(my_stock->db_home_dir) + strlen(INVENTORYDB) + 1;
my_stock->inventory_db_name = malloc(size);
snprintf(my_stock->inventory_db_name, size, "%s%s",
my_stock->db_home_dir, INVENTORYDB);
/* Create the Vendor DB file name */
size = strlen(my_stock->db_home_dir) + strlen(VENDORDB) + 1;
my_stock->vendor_db_name = malloc(size);
snprintf(my_stock->vendor_db_name, size, "%s%s",
my_stock->db_home_dir, VENDORDB);
/* Create the itemname DB file name */
size = strlen(my_stock->db_home_dir) + strlen(ITEMNAMEDB) + 1;
my_stock->itemname_db_name = malloc(size);
snprintf(my_stock->itemname_db_name, size, "%s%s",
my_stock->db_home_dir, ITEMNAMEDB);
}
/* Closes all the databases and secondary databases. */
int
databases_close(STOCK_DBS *my_stock)
{
int ret;
/*
* Note that closing a database automatically flushes its cached data
* to disk, so no sync is required here.
*/
if (my_stock->itemname_sdbp != NULL) {
ret = my_stock->itemname_sdbp->close(my_stock->itemname_sdbp, 0);
if (ret != 0)
fprintf(stderr, "Itemname database close failed: %s\n",
db_strerror(ret));
}
if (my_stock->inventory_dbp != NULL) {
ret = my_stock->inventory_dbp->close(my_stock->inventory_dbp, 0);
if (ret != 0)
fprintf(stderr, "Inventory database close failed: %s\n",
db_strerror(ret));
}
if (my_stock->vendor_dbp != NULL) {
ret = my_stock->vendor_dbp->close(my_stock->vendor_dbp, 0);
if (ret != 0)
fprintf(stderr, "Vendor database close failed: %s\n",
db_strerror(ret));
}
printf("databases closed.\n");
return (0);
}
|
