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/* File: example_database_load.c */
/* We assume an ANSI-compatible compiler */
#include "gettingstarted_common.h"
/* Forward declarations */
int usage(void);
int load_vendors_database(STOCK_DBS, char *);
int pack_string(char *, char *, int);
int load_inventory_database(STOCK_DBS, char *);
int
usage()
{
fprintf(stderr, "example_database_load [-b <path to data files>]");
fprintf(stderr, " [-h <database_home_directory>]\n");
fprintf(stderr, "\tNote: Any path specified must end with your");
fprintf(stderr, " system's path delimiter (/ or \\)\n");
return (-1);
}
/*
* Loads the contents of vendors.txt and inventory.txt into
* Berkeley DB databases. Also causes the itemname secondary
* database to be created and loaded.
*/
int
main(int argc, char *argv[])
{
STOCK_DBS my_stock;
int ch, ret, size;
char *basename, *inventory_file, *vendor_file;
extern char *optarg;
/* Initialize the STOCK_DBS struct */
initialize_stockdbs(&my_stock);
/* Initialize the base path. */
basename = "./";
/* Parse the command line arguments */
while ((ch = getopt(argc, argv, "b:h:")) != EOF)
switch (ch) {
case 'h':
if (optarg[strlen(optarg)-1] != '/' &&
optarg[strlen(optarg)-1] != '\\')
return (usage());
my_stock.db_home_dir = optarg;
break;
case 'b':
if (basename[strlen(basename)-1] != '/' &&
basename[strlen(basename)-1] != '\\')
return (usage());
basename = optarg;
break;
case '?':
default:
return (usage());
}
/* Identify the files that will hold our databases */
set_db_filenames(&my_stock);
/* Find our input files */
size = strlen(basename) + strlen(INVENTORY_FILE) + 1;
inventory_file = malloc(size);
snprintf(inventory_file, size, "%s%s", basename, INVENTORY_FILE);
size = strlen(basename) + strlen(VENDORS_FILE) + 1;
vendor_file = malloc(size);
snprintf(vendor_file, size, "%s%s", basename, VENDORS_FILE);
/* Open all databases */
ret = databases_setup(&my_stock, "example_database_load", stderr);
if (ret) {
fprintf(stderr, "Error opening databases\n");
databases_close(&my_stock);
return (ret);
}
ret = load_vendors_database(my_stock, vendor_file);
if (ret) {
fprintf(stderr, "Error loading vendors database.\n");
databases_close(&my_stock);
return (ret);
}
ret = load_inventory_database(my_stock, inventory_file);
if (ret) {
fprintf(stderr, "Error loading inventory database.\n");
databases_close(&my_stock);
return (ret);
}
/* close our environment and databases */
databases_close(&my_stock);
printf("Done loading databases.\n");
return (ret);
}
/*
* Loads the contents of the vendors.txt file into
* a database.
*/
int
load_vendors_database(STOCK_DBS my_stock, char *vendor_file)
{
DBT key, data;
char buf[MAXLINE];
FILE *ifp;
VENDOR my_vendor;
/* Load the vendors database */
ifp = fopen(vendor_file, "r");
if (ifp == NULL) {
fprintf(stderr, "Error opening file '%s'\n", vendor_file);
return (-1);
}
while (fgets(buf, MAXLINE, ifp) != NULL) {
/* zero out the structure */
memset(&my_vendor, 0, sizeof(VENDOR));
/* Zero out the DBTs */
memset(&key, 0, sizeof(DBT));
memset(&data, 0, sizeof(DBT));
/*
* Scan the line into the structure.
* Convenient, but not particularly safe.
* In a real program, there would be a lot more
* defensive code here.
*/
sscanf(buf,
"%20[^#]#%20[^#]#%20[^#]#%3[^#]#%6[^#]#%13[^#]#%20[^#]#%20[^\n]",
my_vendor.name, my_vendor.street,
my_vendor.city, my_vendor.state,
my_vendor.zipcode, my_vendor.phone_number,
my_vendor.sales_rep, my_vendor.sales_rep_phone);
/* Now that we have our structure we can load it into the database. */
/* Set up the database record's key */
key.data = my_vendor.name;
key.size = (strlen(my_vendor.name) + 1) * sizeof(char);
/* Set up the database record's data */
data.data = &my_vendor;
data.size = sizeof(VENDOR);
/*
* Note that given the way we built our struct, there's extra
* bytes in it. Essentially we're using fixed-width fields with
* the unused portion of some fields padded with zeros. This
* is the easiest thing to do, but it does result in a bloated
* database. Look at load_inventory_data() for an example of how
* to avoid this.
*/
/* Put the data into the database */
my_stock.vendor_dbp->put(my_stock.vendor_dbp, 0, &key, &data, 0);
} /* end vendors database while loop */
fclose(ifp);
return (0);
}
/*
* Simple little convenience function that takes a buffer, a string,
* and an offset and copies that string into the buffer at the
* appropriate location. Used to ensure that all our strings
* are contained in a single contiguous chunk of memory.
*/
int
pack_string(char *buffer, char *string, int start_pos)
{
int string_size;
string_size = strlen(string) + 1;
memcpy(buffer+start_pos, string, string_size);
return (start_pos + string_size);
}
/*
* Loads the contents of the inventory.txt file into
* a database. Note that because the itemname
* secondary database is associated to the inventorydb
* (see env_setup() in gettingstarted_common.c), the
* itemname index is automatically created when this
* database is loaded.
*/
int
load_inventory_database(STOCK_DBS my_stock, char *inventory_file)
{
DBT key, data;
char buf[MAXLINE];
char databuf[MAXDATABUF];
int bufLen, dataLen;
FILE *ifp;
/*
* Rather than lining everything up nicely in a struct, we're being
* deliberately a bit sloppy here. This function illustrates how to
* store mixed data that might be obtained from various locations
* in your application.
*/
float price;
int quantity;
char category[MAXFIELD], name[MAXFIELD];
char vendor[MAXFIELD], sku[MAXFIELD];
/* Load the inventory database */
ifp = fopen(inventory_file, "r");
if (ifp == NULL) {
fprintf(stderr, "Error opening file '%s'\n", inventory_file);
return (-1);
}
while (fgets(buf, MAXLINE, ifp) != NULL) {
/*
* Scan the line into the appropriate buffers and variables.
* Convenient, but not particularly safe. In a real
* program, there would be a lot more defensive code here.
*/
sscanf(buf,
"%20[^#]#%20[^#]#%f#%i#%20[^#]#%20[^\n]",
name, sku, &price, &quantity, category, vendor);
/*
* Now pack it into a single contiguous memory location for
* storage.
*/
memset(databuf, 0, MAXDATABUF);
bufLen = 0;
dataLen = 0;
dataLen = sizeof(float);
memcpy(databuf, &price, dataLen);
bufLen += dataLen;
dataLen = sizeof(int);
memcpy(databuf + bufLen, &quantity, dataLen);
bufLen += dataLen;
bufLen = pack_string(databuf, name, bufLen);
bufLen = pack_string(databuf, sku, bufLen);
bufLen = pack_string(databuf, category, bufLen);
bufLen = pack_string(databuf, vendor, bufLen);
/* Zero out the DBTs */
memset(&key, 0, sizeof(DBT));
memset(&data, 0, sizeof(DBT));
/* The key is the item's SKU */
key.data = sku;
key.size = strlen(sku) + 1;
/* The data is the information that we packed into databuf. */
data.data = databuf;
data.size = bufLen;
/* Put the data into the database */
my_stock.vendor_dbp->put(my_stock.inventory_dbp, 0, &key, &data, 0);
} /* end vendors database while loop */
/* Cleanup */
fclose(ifp);
return (0);
}
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