int db_walk(void *dbh, int (*walk_func)(char *key, void *data, int len))
{
DBT key, data;
DBC *dbc;
int rc = 0;
GET_DB(dbh);
if (!walk_func)
return -EINVAL;
if ((rc = db->cursor(db, NULL, &dbc, 0))) {
db->close(db, 0);
return rc;
}
memset(&key, 0, sizeof(key));
memset(&data, 0, sizeof(data));
while (dbc->c_get(dbc, &key, &data, DB_NEXT) == 0)
if ((rc = walk_func(key.data, data.data, data.size)))
break;
dbc->c_close(dbc);
return rc;
}
int db_close(void *dbh)
{
GET_DB(dbh);
if (db == global_db)
db_close_global();
else
db->close(db, 0);
return 0;
}
int db_del(void *dbh, char *keystr)
{
DBT key;
GET_DB(dbh);
memset(&key, 0, sizeof(key));
key.data = keystr;
key.size = strlen(key.data) + 1;
return db->del(db, NULL, &key, 0);
}
/* Returns 0 on success */
int db_put(void *dbh, char *keystr, void *val, int len, unsigned flags)
{
DBT key, data;
GET_DB(dbh);
memset(&key, 0, sizeof(key));
memset(&data, 0, sizeof(data));
key.data = keystr;
key.size = strlen(keystr) + 1;
if (len) {
data.data = val;
data.size = len;
}
return db->put(db, NULL, &key, &data, flags);
}
/* Returns val len on success */
int db_get(void *dbh, char *keystr, void *val, int len)
{
DBT key, data;
GET_DB(dbh);
memset(&key, 0, sizeof(key));
memset(&data, 0, sizeof(data));
key.data = keystr;
key.size = strlen(keystr) + 1;
int rc = db->get(db, NULL, &key, &data, 0);
if (rc)
return rc < 0 ? rc : -rc;
if (len > data.size)
len = data.size;
memcpy(val, data.data, len);
return len;
}
/**
* Called by kernel for each new netlink socket message receieved
*/
static void kr_nl_recv(struct sk_buff *skb) {
struct nlmsghdr * nlh = (struct nlmsghdr *)skb->data;
kr_dataptr data = nlmsg_data(nlh);
int size = nlmsg_len(nlh);
int pid = nlh->nlmsg_pid;
int seq = nlh->nlmsg_seq;
KrDb* db = NULL; /* used differently by all switch cases */
KrOutbuf outbuf = kr_outbuf(sizeof(u64));
/* helper macros for reading message data */
#define NEXT_U8() (*(u8* )((data += sizeof(u8)) - sizeof(u8)))
#define NEXT_U64() (*(u64*)((data += sizeof(u64)) - sizeof(u64)))
#define NEXT_PTR(len) ((data += len) - len)
#define GET_DB() do { \
db = kr_db_from_id(NEXT_U8()); \
if (!db) { \
printk(KERN_INFO "GET_DB WITH INVALID ID\n"); \
return; \
} \
} while (0)
/* -------------- command type switch */
switch (nlh->nlmsg_type) {
//--------------------------------------------------
// Command: OPEN
//--------------------------------------------------
case KR_COMMAND_OPEN: {
const char * path = (const char *)data;
printk(KERN_INFO "KR_COMMAND_OPEN - \"%s\"\n", path);
kr_db_open(&db, path);
kr_nl_send(pid, seq, KR_COMMAND_OPEN, &db->id, sizeof(db->id));
break;
}
//--------------------------------------------------
// Command: Close
//--------------------------------------------------
case KR_COMMAND_CLOSE: {
GET_DB();
//kr_db_close(db);
break;
}
//--------------------------------------------------
// Command: PUT
//--------------------------------------------------
case KR_COMMAND_PUT: {
KrSlice key, val;
GET_DB();
key.size = NEXT_U64();
key.data = NEXT_PTR(key.size);
val.size = NEXT_U64();
val.data = NEXT_PTR(val.size);
kr_db_put(db, key, val);
break;
}
//--------------------------------------------------
// Command: GET
//--------------------------------------------------
case KR_COMMAND_GET: {
u64 size;
KrSlice key;
GET_DB();
key.size = NEXT_U64();
key.data = NEXT_PTR(key.size);
kr_db_get(db, key, &outbuf, &size);
*(u64 *)outbuf.data = size;
kr_nl_send(pid, seq, KR_COMMAND_GET, outbuf.data, sizeof(u64) + size);
break;
}
//--------------------------------------------------
// Command: BENCH
//--------------------------------------------------
case KR_COMMAND_BENCH: {
GET_DB();
printk(KERN_INFO "Running kr_bench(\"%s\")...\n", db->path);
kr_bench(db);
printk(KERN_INFO "...done.\n");
}
case KR_COMMAND_NOP:
default:
printk(KERN_INFO "Received unknown command\n");
break;
}
}
