When in doubt, use the source - or in this case RFC2616
ยง4.4.<http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.4>
TL;DR version - the length is indicated by one of three situations:
1. A Content-Length header exists
2. Transfer-Encoding is "chunked", in which case each chunk (there can be
several) begins with a length in hex. A zero length chunk terminates the
grouping and the trailer is terminated with a CRLF.
3. Otherwise when the connection is closed.
Read the RFC for all the gory details.
On 11 January 2014 23:45, M. V. <bored_to_deat...@yahoo.com> wrote:
> Hi Matthew,
>
> but from what I know, not all HTTP responses have "Content-Length" field.
> responses with "chunked" payload are one of them. what can I do then?
>
> Thank you.
>
>
>
>
> On Saturday, January 11, 2014 1:23 PM, Matthew Donald <
> matthew.b.don...@gmail.com> wrote:
>
> Sockets (SSL or otherwise) are layer-3 objects while content is a layer-7
> object. To get an accurate end-of-content marker, you'll need to parse the
> output, buts since you are using the https protocol, that's going to be
> easy.
>
> Essentially, parse out the "Content-Length" header and read that many
> bytes past the end of the http headers.
>
>
>
>
> On 11 January 2014 19:46, M. V. <bored_to_deat...@yahoo.com> wrote:
>
> Hi everybody,
>
> I'm writing an application that creates multiple non-blocking SSL
> connections to an https server, in each one I send a request and read the
> server's response. my problem is, whatever I do, I can't determine when the
> response data is finished. here's part of my code responsible for sending
> and receiving data:
>
> ....
> fd_set connectionfds;struct timeval timeout2;
> FD_ZERO(&connectionfds);
> FD_SET(socket_server, &connectionfds);
> timeout2.tv_usec = 0;
> timeout2.tv_sec = 1;while(1){
> r=BIO_read(io,buf,BUFSIZZ-1);
> if (r>0){
> //gather data
> continue;
> }
> else if (SSL_get_error(ssl, r)==SSL_ERROR_WANT_READ){
> int ret = select(socket_server + 1, &connectionfds, NULL, NULL,
> &timeout2);
> if (ret <= 0){
> break;
> }
> continue;
> }
> else{
> break;
> }}// use whole gathered data....
>
> my problem with above code is, if I set select timeout to a small time, I
> can't guarantee that all data is received (because some servers are really
> slow), and if I set timeout to a long time (5-10 seconds), my socket is
> getting stucked in wait-state for a long time and I can't use the response
> before that. I tried to make this work by using "BIO_should_read()" or
> "BIO_pending()" functions, but none of them is giving me what I want. so,
> Is there a way to determine when exactly there is nothing else to read on
> the SSL socket?
>
> Thank you.
>
>
>
>
>
