source: protocols/http_client.c @ 8a9afe4

  /********************************************************************\
  * BitlBee -- An IRC to other IM-networks gateway                     *
  *                                                                    *
  * Copyright 2002-2005 Wilmer van der Gaast and others                *
  \********************************************************************/

/* HTTP(S) module (actually, it only does HTTPS right now)              */

/*
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License with
  the Debian GNU/Linux distribution in /usr/share/common-licenses/GPL;
  if not, write to the Free Software Foundation, Inc., 59 Temple Place,
  Suite 330, Boston, MA  02111-1307  USA
*/

#include <string.h>

#include "sock.h"
#include "http_client.h"


static void http_connected( gpointer data, int source, GaimInputCondition cond );
static void http_ssl_connected( gpointer data, void *source, GaimInputCondition cond );
static void http_incoming_data( gpointer data, int source, GaimInputCondition cond );


void *http_dorequest( char *host, int port, http_input_function func, int ssl, char *request, gpointer data )
{
        struct http_request *req;
        int error = 0;
        
        req = g_new0( struct http_request, 1 );
        
        if( ssl )
        {
                req->ssl = ssl_connect( host, port, http_ssl_connected, req );
                if( req->ssl == NULL )
                        error = 1;
        }
        else
        {
                req->fd = proxy_connect( host, port, http_connected, req );
                if( req->fd < 0 )
                        error = 1;
        }
        
        if( error )
        {
                g_free( req );
                return( NULL );
        }
        
        req->request = g_strdup( request );
        req->request_length = strlen( request );
        
        return( req );
}

/* This one is actually pretty simple... Might get more calls if we can't write 
   the whole request at once. */
static void http_connected( gpointer data, int source, GaimInputCondition cond )
{
        struct http_request *req = data;
        int st;
        
        if( source < 0 )
                goto error;
        
        if( req->inpa > 0 )
                gaim_input_remove( req->inpa );
        
        sock_make_nonblocking( req->fd );
        
        if( req->ssl )
        {
                st = ssl_write( req->ssl, req->request + req->bytes_written,
                                req->request_length - req->bytes_written );
                if( st < 0 )
                {
                        if( ssl_errno != SSL_AGAIN )
                        {
                                ssl_disconnect( req->ssl );
                                goto error;
                        }
                }
        }
        else
        {
                st = write( source, req->request + req->bytes_written,
                                    req->request_length - req->bytes_written );
                if( st < 0 )
                {
                        if( !sockerr_again() )
                        {
                                close( req->fd );
                                goto error;
                        }
                }
        }
        
        if( st > 0 )
                req->bytes_written += st;
        
        if( req->bytes_written < req->request_length )
                req->inpa = gaim_input_add( source,
                                            req->ssl ? ssl_getdirection( req->ssl ) : GAIM_INPUT_WRITE,
                                            http_connected, req );
        else
                req->inpa = gaim_input_add( source, GAIM_INPUT_READ, http_incoming_data, req );
        
        return;
        
error:
        req->func( req );
        
        g_free( req->request );
        g_free( req );
        
        return;
}

static void http_ssl_connected( gpointer data, void *source, GaimInputCondition cond )
{
        struct http_request *req = data;
        
        if( source == NULL )
                return http_connected( data, -1, cond );
        
        req->fd = ssl_getfd( source );
        
        return http_connected( data, req->fd, cond );
}

static void http_incoming_data( gpointer data, int source, GaimInputCondition cond )
{
        struct http_request *req = data;
        int evil_server = 0;
        char buffer[2048];
        char *end1, *end2;
        int st;
        
        if( req->inpa > 0 )
                gaim_input_remove( req->inpa );
        
        if( req->ssl )
        {
                st = ssl_read( req->ssl, buffer, sizeof( buffer ) );
                if( st < 0 )
                {
                        if( ssl_errno != SSL_AGAIN )
                        {
                                goto cleanup;
                        }
                }
                else if( st == 0 )
                {
                        goto got_reply;
                }
        }
        else
        {
                st = read( req->fd, buffer, sizeof( buffer ) );
                if( st < 0 )
                {
                        if( !sockerr_again() )
                        {
                                goto cleanup;
                        }
                }
                else if( st == 0 )
                {
                        goto got_reply;
                }
        }
        
        if( st > 0 )
        {
                req->reply_headers = g_realloc( req->reply_headers, req->bytes_read + st + 1 );
                memcpy( req->reply_headers + req->bytes_read, buffer, st );
        }
        
        /* There will be more! */
        req->inpa = gaim_input_add( req->fd,
                                    req->ssl ? ssl_getdirection( req->ssl ) : GAIM_INPUT_READ,
                                    http_incoming_data, req );
        
        return;

got_reply:
        /* Zero termination is very convenient. */
        req->reply_headers[req->bytes_read] = 0;
        
        /* Find the separation between headers and body, and keep stupid
           webservers in mind. */
        end1 = strstr( req->reply_headers, "\r\n\r\n" );
        end2 = strstr( req->reply_headers, "\n\n" );
        
        if( end2 && end2 < end1 )
        {
                end1 = end2;
                evil_server = 1;
        }
        
        if( end1 )
        {
                *end1 = 0;
                
                if( evil_server )
                        req->reply_body = end1 + 2;
                else
                        req->reply_body = end1 + 4;
        }
        
        /* Assume that a closed connection means we're finished, this indeed
           breaks with keep-alive connections and faulty connections. */
        req->finished = 1;

cleanup:
        if( req->ssl )
                ssl_disconnect( req->ssl );
        else
                close( req->fd );
        
        req->func( req );
        
        g_free( req->request );
        g_free( req->reply_headers );
        g_free( req );
}