libdill: Structured Concurrency for C

NAME

http_recvfield - receives HTTP field from the peer

SYNOPSIS

#include <libdill.h>

int http_recvfield(
    int s,
    char* name,
    size_t namelen,
    char* value,
    size_t valuelen,
    int64_t deadline);

DESCRIPTION

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 receives an HTTP field from the peer.

s: HTTP socket handle.

name: Buffer to store name of the field.

namelen: Size of the name buffer.

value: Buffer to store value of the field.

valuelen: Size of the value buffer.

deadline: A point in time when the operation should time out, in milliseconds. Use the now function to get your current point in time. 0 means immediate timeout, i.e., perform the operation if possible or return without blocking if not. -1 means no deadline, i.e., the call will block forever if the operation cannot be performed.

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

RETURN VALUE

In case of success the function returns 0. In case of error it returns -1 and sets errno to one of the values below.

ERRORS

EBADF: Invalid handle.
ECANCELED: Current coroutine was canceled.
ECONNRESET: Broken connection.
EINVAL: Invalid argument.
EMSGSIZE: The data won't fit into the supplied buffer.
ENOTSUP: The handle does not support this operation.
EPIPE: There are no more fields to receive.
ETIMEDOUT: Deadline was reached.

EXAMPLE

int s = tcp_connect(&addr, -1);
s = http_attach(s);
http_sendrequest(s, "GET", "/", -1);
http_sendfield(s, "Host", "www.example.org", -1);
http_done(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);
tcp_close(s);