apache/include/http_protocol.h

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2000 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 * Portions of this software are based upon public domain software
 * originally written at the National Center for Supercomputing Applications,
 * University of Illinois, Urbana-Champaign.
 */

#ifndef APACHE_HTTP_PROTOCOL_H
#define APACHE_HTTP_PROTOCOL_H

#include "ap_hooks.h"
#include "apr_portable.h"
#include "apr_mmap.h"

#ifdef __cplusplus
extern "C" {
#endif

/*
 * Prototypes for routines which either talk directly back to the user,
 * or control the ones that eventually do.
 */

/* Read a request and fill in the fields. */

request_rec *ap_read_request(conn_rec *c);

/* Send a single HTTP header field */

API_EXPORT_NONSTD(int) ap_send_header_field(request_rec *r, const char *fieldname,
                      const char *fieldval);

/* Send the minimal part of an HTTP response header... but modules should be
 * very careful about using this, and should prefer ap_send_http_header().
 * Much of the HTTP/1.1 implementation correctness depends on code in
 * ap_send_http_header().
 */
API_EXPORT(void) ap_basic_http_header(request_rec *r);

/* Send the Status-Line and header fields for HTTP response */

API_EXPORT(void) ap_send_http_header(request_rec *l);

/* Send the response to special method requests */

API_EXPORT(int) ap_send_http_trace(request_rec *r);
int ap_send_http_options(request_rec *r);

/* Finish up stuff after a request */

API_EXPORT(void) ap_finalize_request_protocol(request_rec *r);

/* Send error back to client... last arg indicates error status in case
 * we get an error in the process of trying to deal with an ErrorDocument
 * to handle some other error.  In that case, we print the default report
 * for the first thing that went wrong, and more briefly report on the
 * problem with the ErrorDocument.
 */

API_EXPORT(void) ap_send_error_response(request_rec *r, int recursive_error);

/* Set last modified header line from the lastmod date of the associated file.
 * Also, set content length.
 *
 * May return an error status, typically HTTP_NOT_MODIFIED (that when the
 * permit_cache argument is set to one).
 */

API_EXPORT(int) ap_set_content_length(request_rec *r, long length);
API_EXPORT(int) ap_set_keepalive(request_rec *r);
API_EXPORT(ap_time_t) ap_rationalize_mtime(request_rec *r, ap_time_t mtime);
API_EXPORT(char *) ap_make_etag(request_rec *r, int force_weak);
API_EXPORT(void) ap_set_etag(request_rec *r);
API_EXPORT(void) ap_set_last_modified(request_rec *r);
API_EXPORT(int) ap_meets_conditions(request_rec *r);

/* Other ways to send stuff at the client.  All of these keep track
 * of bytes_sent automatically.  This indirection is intended to make
 * it a little more painless to slide things like HTTP-NG packetization
 * underneath the main body of the code later.  In the meantime, it lets
 * us centralize a bit of accounting (bytes_sent).
 *
 * These also return the number of bytes written by the call.
 * They should only be called with a timeout registered, for obvious reaasons.
 * (Ditto the send_header stuff).
 */

API_EXPORT(ap_status_t) ap_send_fd(ap_file_t *fd, request_rec *r, ap_off_t offset, 
                                   ap_size_t length, ap_size_t *nbytes);

API_EXPORT(long) ap_send_fb(BUFF *f, request_rec *r);
API_EXPORT(long) ap_send_fb_length(BUFF *f, request_rec *r, long length);

API_EXPORT(size_t) ap_send_mmap(ap_mmap_t *mm, request_rec *r, size_t offset,
                             size_t length);

/* Hmmm... could macrofy these for now, and maybe forever, though the
 * definitions of the macros would get a whole lot hairier.
 */

API_EXPORT(int) ap_rputc(int c, request_rec *r);
API_EXPORT(int) ap_rputs(const char *str, request_rec *r);
API_EXPORT(int) ap_rwrite(const void *buf, int nbyte, request_rec *r);
API_EXPORT_NONSTD(int) ap_rvputs(request_rec *r,...);
API_EXPORT(int) ap_vrprintf(request_rec *r, const char *fmt, va_list vlist);
API_EXPORT_NONSTD(int) ap_rprintf(request_rec *r, const char *fmt,...)
				__attribute__((format(printf,2,3)));
API_EXPORT(int) ap_rflush(request_rec *r);

/*
 * Index used in custom_responses array for a specific error code
 * (only use outside protocol.c is in getting them configured).
 */

API_EXPORT(int) ap_index_of_response(int status);

/* 
 * Return the Status-Line for a given status code (excluding the
 * HTTP-Version field). If an invalid or unknown status code is
 * passed, "500 Internal Server Error" will be returned. 
 */
API_EXPORT(const char *) ap_get_status_line(int status);

/* Reading a block of data from the client connection (e.g., POST arg) */

API_EXPORT(int) ap_setup_client_block(request_rec *r, int read_policy);
API_EXPORT(int) ap_should_client_block(request_rec *r);
API_EXPORT(long) ap_get_client_block(request_rec *r, char *buffer, int bufsiz);
API_EXPORT(int) ap_discard_request_body(request_rec *r);

/* Sending a byterange */

API_EXPORT(int) ap_set_byterange(request_rec *r);
API_EXPORT(int) ap_each_byterange(request_rec *r, ap_off_t *offset,
				  ap_size_t *length);

/* Support for the Basic authentication protocol.  Note that there's
 * nothing that prevents these from being in mod_auth.c, except that other
 * modules which wanted to provide their own variants on finding users and
 * passwords for Basic auth (a fairly common request) would then require
 * mod_auth to be loaded or they wouldn't work.
 *
 * get_basic_auth_pw returns 0 (OK) if it set the 'pw' argument (and assured
 * a correct value in r->connection->user); otherwise it returns an error
 * code, either HTTP_INTERNAL_SERVER_ERROR if things are really confused,
 * HTTP_UNAUTHORIZED if no authentication at all seemed to be in use, or
 * DECLINED if there was authentication but it wasn't Basic (in which case,
 * the caller should presumably decline as well).
 *
 * note_basic_auth_failure arranges for the right stuff to be scribbled on
 * the HTTP return so that the client knows how to authenticate itself the
 * next time. As does note_digest_auth_failure for Digest auth.
 *
 * note_auth_failure does the same thing, but will call the correct one
 * based on the authentication type in use.
 *
 */

API_EXPORT(void) ap_note_auth_failure(request_rec *r);
API_EXPORT(void) ap_note_basic_auth_failure(request_rec *r);
API_EXPORT(void) ap_note_digest_auth_failure(request_rec *r);
API_EXPORT(int) ap_get_basic_auth_pw(request_rec *r, const char **pw);

/*
 * Setting up the protocol fields for subsidiary requests...
 * Also, a wrapup function to keep the internal accounting straight.
 */

void ap_set_sub_req_protocol(request_rec *rnew, const request_rec *r);
void ap_finalize_sub_req_protocol(request_rec *sub_r);

/* This is also useful for putting sub_reqs and internal_redirects together */

CORE_EXPORT(void) ap_parse_uri(request_rec *r, const char *uri);

/* Get the method number associated with the given string, assumed to
 * contain an HTTP method.  Returns M_INVALID if not recognized.
 */
API_EXPORT(int) ap_method_number_of(const char *method);

  /* Hooks */
  /*
   * post_read_request --- run right after read_request or internal_redirect,
   *                  and not run during any subrequests.
   */
AP_DECLARE_HOOK(int,post_read_request,(request_rec *))
AP_DECLARE_HOOK(int,log_transaction,(request_rec *))
AP_DECLARE_HOOK(const char *,http_method,(const request_rec *))
AP_DECLARE_HOOK(unsigned short,default_port,(const request_rec *))

#ifdef __cplusplus
}
#endif

#endif	/* !APACHE_HTTP_PROTOCOL_H */