Ｗith his 100th birthday on Thursday, cards have flooded in from members of the public wanting to share their appreaciation and wish him a special day.

请问老师，画线的部分是作什么成分的。the public wanting to share their appreaciation and wish him a special day是复合结构，还是wanting to share their appreaciation and wish him a special day作the public的后置定语？