http-get-apr.c

#include <string.h>
#include <stdio.h>
#include <stdlib.h>

#include <apr-1/apr_general.h>
#include <apr-1/apr_network_io.h>
#include <apr-1/apr_strings.h>

#define REMOTE_HOST  "localhost"
#define REMOTE_PORT  8000
#define SOCK_TIMEOUT  (APR_USEC_PER_SEC * 30)
#define BUFSIZE  4096
#define CRLF  "\r\n"

static apr_status_t do_connect(apr_socket_t **sock, apr_pool_t *mp)
{
    apr_sockaddr_t *sa;
    apr_socket_t *s;
    apr_status_t rv;
    
    rv = apr_sockaddr_info_get(&sa, REMOTE_HOST, APR_UNSPEC, REMOTE_PORT, 0, mp);
    if (rv != APR_SUCCESS) {
        return rv;
    }
    
    for ( ; sa; sa = sa->next) {
        rv = apr_socket_create(&s, sa->family, SOCK_STREAM, APR_PROTO_TCP, mp);
        if (rv != APR_SUCCESS) {
            return rv;
        }

        apr_socket_opt_set(s, APR_SO_NONBLOCK, 1);
        apr_socket_timeout_set(s, SOCK_TIMEOUT);

        rv = apr_socket_connect(s, sa);
        if (rv == ECONNREFUSED) {
            continue;
        } else if (rv == APR_SUCCESS) {
            break;
        } else {
            return rv;
        }
    }

    apr_socket_opt_set(s, APR_SO_NONBLOCK, 0);
    apr_socket_timeout_set(s, SOCK_TIMEOUT);

    *sock = s;
    return APR_SUCCESS;
}

static apr_status_t send_reqeust(apr_socket_t *sock, apr_pool_t *mp)
{
    apr_status_t rv;
    const char request[] = "GET / HTTP/1.0" CRLF
        "Host: " REMOTE_HOST CRLF
        CRLF;
    apr_size_t len = strlen(request);
    rv = apr_socket_send(sock, request, &len);
    if (rv != APR_SUCCESS) {
        return rv;
    }

    apr_file_t *stdout;
    apr_file_open_stdout(&stdout, mp);

    while (1) {
        char buf[BUFSIZE];
        apr_size_t len = sizeof(buf);
        
        apr_status_t rv = apr_socket_recv(sock, buf, &len);
        if (rv == APR_EOF || len == 0) {
            break;
        } else if (rv != APR_SUCCESS) {
            return rv;
        }
        apr_file_write(stdout, buf, &len);
    }
    apr_file_close(stdout);

    return APR_SUCCESS;
}

int main(int argc, const char *argv[])
{
    (void)argc;
    (void)argv;
    apr_status_t rv;
    apr_pool_t *mp;
    apr_socket_t *s;

    apr_initialize();
    apr_pool_create(&mp, NULL);

    rv = do_connect(&s, mp);
    if (rv != APR_SUCCESS) {
        goto error;
    }
    
    rv = send_reqeust(s, mp);
    if (rv != APR_SUCCESS) {
        goto error;
    }
    apr_socket_close(s);
    
    apr_terminate();
    exit(EXIT_SUCCESS);

error:
    {
        char errbuf[256];
        apr_strerror(rv, errbuf, sizeof(errbuf));
        printf("error: %d, %s\n", rv, errbuf);
    }
    apr_terminate();
    exit(EXIT_FAILURE);
}