libdill: Structured Concurrency for C


http_attach_mem - creates HTTP protocol on top of underlying socket


#include <libdill.h>

int http_attach_mem(
    int s,
    void* mem);


WARNING: This is experimental functionality and the API may change in the future.

HTTP is an application-level protocol described in RFC 7230. This implementation handles only the request/response exchange. Whatever comes after that must be handled by a different protocol.

This function instantiates HTTP protocol on top of the underlying protocol.

This function allows to avoid one dynamic memory allocation by storing the object in user-supplied memory. Unless you are hyper-optimizing use http_attach instead.

s: Handle of the underlying socket. It must be a bytestream protocol.

mem: The memory to store the newly created object. It must be at least HTTP_SIZE bytes long and must not be deallocated before the object is closed.

The socket can be cleanly shut down using http_detach function.

This function is not available if libdill is compiled with --disable-sockets option.


In case of success the function returns newly created socket handle. In case of error it returns -1 and sets errno to one of the values below.



int s = tcp_connect(&addr, -1);
s = http_attach(s);
http_sendrequest(s, "GET", "/", -1);
http_sendfield(s, "Host", "", -1);
hdone(s, -1);
char reason[256];
http_recvstatus(s, reason, sizeof(reason), -1);
while(1) {
    char name[256];
    char value[256];
    int rc = http_recvfield(s, name, sizeof(name), value, sizeof(value), -1);
    if(rc == -1 && errno == EPIPE) break;
s = http_detach(s, -1);


hclose(3) http_attach(3) http_detach(3) http_recvfield(3) http_recvrequest(3) http_recvstatus(3) http_sendfield(3) http_sendrequest(3) http_sendstatus(3)