Empty request body using Embedded Perl

[杨镭]

Hi all,

We use $r->request_body method from Embedded Perl to process request
body. The problem is although $r->has_request_body() returns 1, the
request body is still evaluated to empty string.

PS: According to the Nginx wiki, when the client body exceeds the
value of client_max_body_size, it will be buffered to file. So we've
already raised client_max_body_size to 30M, but the request body
remains an empty string.