amf0 utest: add usage for amf0

@@ -37,6 +37,35 @@ class SrsStream;
 class SrsAmf0Object;
 class SrsAmf0EcmaArray;
 
+////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////
+// amf0 codec
+// 1. SrsAmf0Any: read any from stream
+//		SrsAmf0Any* pany = NULL;
+//		if ((ret = srs_amf0_read_any(stream, &pany)) != ERROR_SUCCESS) {
+//			return ret;
+// 		}
+// 2. SrsAmf0Any: convert to specifid type, for instance, string
+//		SrsAmf0Any* pany = ...
+//		if (pany && pany->is_string()) {
+//			string v = pany->to_str();
+//		}
+// 3. SrsAmf0Any: parse specified type to any, for instance, string
+//		SrsAmf0Any* pany = SrsAmf0Any::str("winlin");
+// 4. SrsAmf0Size: get amf0 instance size
+//		int size = SrsAmf0Size::str("winlin");
+// 5. SrsAmf0Object: the amf0 object, directly new is ok.
+//		SrsAmf0Object* obj = SrsAmf0Any::object();
+//		SrsAmf0Object* obj = new SrsAmf0Object();
+// 5. SrsAmf0EcmaArray: the amf0 ecma array, directly new is ok.
+//		SrsAmf0EcmaArray* arr = SrsAmf0Any::array();
+//		SrsAmf0EcmaArray* arr = new SrsAmf0EcmaArray();
+// for detail usage, see interfaces of each object.
+////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////
+
 /**
 * any amf0 value.
 * 2.1 Types Overview

@@ -2624,6 +2624,7 @@ int SrsPlayPacket::decode(SrsStream* stream)
     }
     SrsAutoFree(SrsAmf0Any, reset_value, false);
     
+    if (reset_value) {
 	    // check if the value is bool or number
 	    // An optional Boolean value or number that specifies whether
 	    // to flush any previous playlist
@@ -2636,6 +2637,7 @@ int SrsPlayPacket::decode(SrsStream* stream)
 	        srs_error("amf0 invalid type=%#x, requires number or bool, ret=%d", reset_value->marker, ret);
 	        return ret;
 	    }
+    }
 
     srs_info("amf0 decode play packet success");
 	
@@ -3188,7 +3190,7 @@ int SrsOnMetaDataPacket::decode(SrsStream* stream)
 		return ret;
 	}
 	
-	if (any->is_object()) {
+	if (any && any->is_object()) {
 		srs_freep(metadata);
 		metadata = dynamic_cast<SrsAmf0Object*>(any);
 		srs_info("decode metadata object success");
@@ -3199,10 +3201,11 @@ int SrsOnMetaDataPacket::decode(SrsStream* stream)
 	if (!arr) {
 		ret = ERROR_RTMP_AMF0_DECODE;
 		srs_error("decode metadata array failed. ret=%d", ret);
-		srs_freep(any);
 		return ret;
 	}
 	
+	// if ecma array, copy to object.
+	SrsAutoFree(SrsAmf0EcmaArray, arr, false);
 	for (int i = 0; i < arr->size(); i++) {
 		metadata->set(arr->key_at(i), arr->value_at(i));
 	}