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/* SPDX-License-Identifier: BSD-3-Clause */
/*
* Copyright © 2020 rsiddharth <s@ricketyspace.net>
*/
#include <db.h>
static const char *DB_FILE = "nserver.db";
datum *mk_datum(char *data)
{
datum *d = NULL;
check(data != NULL, "data invalid");
d = calloc(1, sizeof(datum));
check(d != NULL, "datum mem alloc failed");
d->dptr = data;
d->dsize = strlen(data);
return d;
error:
if (d) {
free(d);
}
return NULL;
}
GDBM_FILE db_open(int flags)
{
return gdbm_open(DB_FILE, 0,flags, S_IRUSR|S_IWUSR, NULL);
}
int db_init()
{
// Create DB if it's not already created.
GDBM_FILE gf = db_open(GDBM_WRCREAT);
check(gf != NULL, "unable to init db");
// Close the DB.
int rc = gdbm_close(gf);
check(rc == 0, "error closing db after init");
return 0;
error:
return -1;
}
int db_store(char *key, char *value)
{
datum *k_datum = NULL, *v_datum = NULL;
GDBM_FILE gf = NULL;
check(key != NULL && strlen(key) > 0, "key invalid");
check(value != NULL && strlen(value) > 0, "data invalid");
// make key value datum
k_datum = mk_datum(key);
check(k_datum != NULL, "key datum init failed");
v_datum = mk_datum(value);
check(v_datum != NULL, "value datum init failed");
// init db.
int rc = db_init();
check(rc == 0, "db init failed");
// open the gdbm data in write mode
gf = db_open(GDBM_WRITER|GDBM_SYNC);
check(gf != NULL, "unable to open db in write mode");
// write key -> data to db.
rc = gdbm_store(gf, *k_datum, *v_datum, GDBM_REPLACE);
check(rc == 0, "gdbm store failed");
// close db
rc = gdbm_close(gf);
check(rc == 0, "gdbm close failed");
// cleanup.
free(k_datum);
free(v_datum);
return 0;
error:
if (k_datum) {
free(k_datum);
}
if (v_datum) {
free(v_datum);
}
if (gf) {
gdbm_close(gf);
}
return -1;
}
char *db_load(char *key)
{
datum *k_datum = NULL;
GDBM_FILE gf = NULL;
check(key != NULL && strlen(key) > 0, "key invalid");
// make key datum
k_datum = mk_datum(key);
check(k_datum != NULL, "key datum init failed");
// init db.
int rc = db_init();
check(rc == 0, "db init failed");
// open the gdbm data in read mode
gf = db_open(GDBM_READER|GDBM_SYNC);
check(gf != NULL, "unable to open db in read mode");
// try to fetch value for key.
datum v_datum = gdbm_fetch(gf, *k_datum);
check(v_datum.dptr != NULL, "key not found");
// close db
rc = gdbm_close(gf);
check(rc == 0, "gdbm close failed");
// clean up.
free(k_datum);
return v_datum.dptr;
error:
if (k_datum) {
free(k_datum);
}
if (gf) {
gdbm_close(gf);
}
return NULL;
}
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