Added c++ functions:

DbEnv.set_data_dir, DbEnv.set_errpfx

Added tests for them.
Addresses #197

git-svn-id: file:///svn/tokudb@1290 c7de825b-a66e-492c-adef-691d508d4ae1

cxx/dbenv.cpp

@@ -49,3 +49,12 @@ int DbEnv::txn_begin(DbTxn *parenttxn, DbTxn **txnp, u_int32_t flags) {
     }
     return ret;
 }
+
+int DbEnv::set_data_dir(const char *dir) {
+    int ret = the_env->set_data_dir(the_env, dir);
+    return ret;
+}
+
+void DbEnv::set_errpfx(const char *errpfx) {
+    the_env->set_errpfx(the_env, errpfx);
+}

cxx/tests/test1.cpp

@@ -34,10 +34,21 @@ void test_db(void) {
     r = db.remove("DoesNotExist.db", NULL, 0);  assert(r == ENOENT);
 }
 
+void test_db_env(void) {
+    DbEnv dbenv(0);
+    int r;
+    
+    r = dbenv.set_data_dir(".");    assert(r == 0);
+    r = dbenv.set_data_dir("..");   assert(r == 0);
+    r = dbenv.set_data_dir(NULL);   assert(r == EINVAL);
+    dbenv.set_errpfx("Prefix");
+}
+
 int main()
 {
     test_dbt();
     test_db();
+    test_db_env();
     cout << "Hello World!" << endl;   cout << "Welcome to C++ Programming" << endl;
     return 0;
 }

include/db_cxx.h

@@ -96,7 +96,8 @@ class DbEnv {
     int set_lk_max(u_int32_t);
 #endif
     int txn_begin(DbTxn *, DbTxn **, u_int32_t);
-
+    int set_data_dir(const char *dir);
+    void set_errpfx(const char *errpfx);
 
  private:
     DB_ENV *the_env;