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#include "db.hh"
#include "util.hh"
#include <memory>
#include <db_cxx.h>
/* Wrapper classes that ensures that the database is closed upon
object destruction. */
class Db2 : public Db
{
public:
Db2(DbEnv *env, u_int32_t flags) : Db(env, flags) { }
~Db2() { close(0); }
};
class DbcClose
{
Dbc * cursor;
public:
DbcClose(Dbc * c) : cursor(c) { }
~DbcClose() { cursor->close(); }
};
static auto_ptr<Db2> openDB(const string & filename, const string & dbname,
bool readonly)
{
auto_ptr<Db2> db(new Db2(0, 0));
db->open(filename.c_str(), dbname.c_str(),
DB_HASH, readonly ? DB_RDONLY : DB_CREATE, 0666);
return db;
}
static void rethrow(DbException & e)
{
throw Error(e.what());
}
void createDB(const string & filename, const string & dbname)
{
try {
openDB(filename, dbname, false);
} catch (DbException e) { rethrow(e); }
}
bool queryDB(const string & filename, const string & dbname,
const string & key, string & data)
{
try {
int err;
auto_ptr<Db2> db = openDB(filename, dbname, true);
Dbt kt((void *) key.c_str(), key.length());
Dbt dt;
err = db->get(0, &kt, &dt, 0);
if (err) return false;
if (!dt.get_data())
data = "";
else
data = string((char *) dt.get_data(), dt.get_size());
} catch (DbException e) { rethrow(e); }
return true;
}
bool queryListDB(const string & filename, const string & dbname,
const string & key, Strings & data)
{
string d;
if (!queryDB(filename, dbname, key, d))
return false;
string::iterator it = d.begin();
while (it != d.end()) {
if (it + 4 > d.end())
throw Error(format("short db entry: `%1%'") % d);
unsigned int len;
len = (unsigned char) *it++;
len |= ((unsigned char) *it++) << 8;
len |= ((unsigned char) *it++) << 16;
len |= ((unsigned char) *it++) << 24;
if (it + len > d.end())
throw Error(format("short db entry: `%1%'") % d);
string s;
while (len--) s += *it++;
data.push_back(s);
}
return true;
}
void setDB(const string & filename, const string & dbname,
const string & key, const string & data)
{
try {
auto_ptr<Db2> db = openDB(filename, dbname, false);
Dbt kt((void *) key.c_str(), key.length());
Dbt dt((void *) data.c_str(), data.length());
db->put(0, &kt, &dt, 0);
} catch (DbException e) { rethrow(e); }
}
void setListDB(const string & filename, const string & dbname,
const string & key, const Strings & data)
{
string d;
for (Strings::const_iterator it = data.begin();
it != data.end(); it++)
{
string s = *it;
unsigned int len = s.size();
d += len & 0xff;
d += (len >> 8) & 0xff;
d += (len >> 16) & 0xff;
d += (len >> 24) & 0xff;
d += s;
}
setDB(filename, dbname, key, d);
}
void delDB(const string & filename, const string & dbname,
const string & key)
{
try {
auto_ptr<Db2> db = openDB(filename, dbname, false);
Dbt kt((void *) key.c_str(), key.length());
db->del(0, &kt, 0);
} catch (DbException e) { rethrow(e); }
}
void enumDB(const string & filename, const string & dbname,
DBPairs & contents)
{
try {
auto_ptr<Db2> db = openDB(filename, dbname, true);
Dbc * cursor;
db->cursor(0, &cursor, 0);
DbcClose cursorCloser(cursor);
Dbt kt, dt;
while (cursor->get(&kt, &dt, DB_NEXT) != DB_NOTFOUND) {
string key((char *) kt.get_data(), kt.get_size());
string data((char *) dt.get_data(), dt.get_size());
contents.push_back(DBPair(key, data));
}
} catch (DbException e) { rethrow(e); }
}
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