the sy_upload is finish implementing, but still some problems...

[uniray7]

1. whenever sy_upload(client side) finish uploading files, the rtcdc_loop needs to be closed.
   when the rtcdc_peer_connection->exit_thread = 1, the whole function will terminate in about 10 secs
   I observe the process with gdb, the message "[Inferior 1 (process 19439) exited with code 01]" is printed. It seems a thread is abnormally terminated. Also, the other threads include main thread are abnormally terminated.
2. librtcdc has some memory leak problems
3. librtcdc terminate functions, like destroy_peer...(), destroy_sctp...(), seem unfinished
4. sy uses libuv, but sometimes problems. for example, I use uv_queue_work() to run rtcdc_loop() in file_server.c, it needs to sleep(3), or core dump
   btw,librtcdc uses pthread(?) and gthread, and sy use libuv , it needs to be integrated