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/* File: gettingstarted_common.c */
#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 = strlen(skey->data) + 1;
return (0);
}
/* Opens a database */
int
open_database(DB **dbpp, const char *file_name,
const char *program_name, 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 (0);
/*
* 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->vendor_db_name = NULL;
my_stock->inventory_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);
}
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