[osal]: add environment detection function

1. add software runtime detection
2. add hardware platform detection

Change-Id: I75736ae85130325029023d948e4d756e27953af8
Signed-off-by: Herman Chen <herman.chen@rock-chips.com>

osal/mpp_runtime.cpp

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2015 Rockchip Electronics Co. LTD
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifdef RKPLATFORM
+#include <dlfcn.h>
+#endif
+
+#include "mpp_runtime.h"
+
+static func_mmap64 mpp_rt_mmap64 = NULL;
+
+func_mmap64 mpp_rt_get_mmap64()
+{
+#ifdef RKPLATFORM
+    static RK_U32 once = 1;
+
+    if (once) {
+        void *libc_hdl = dlopen("libc", RTLD_LAZY);
+        if (libc_hdl) {
+            mpp_rt_mmap64 = (func_mmap64)dlsym(libc_hdl, "mmap64");
+            dlclose(libc_hdl);
+        }
+
+        once = 0;
+    }
+#endif
+
+    return mpp_rt_mmap64;
+}
+