| blob | bb3e76997a85777f9bc83629b5bfb49ebc61e108 |
1 ;;; url-http.el --- HTTP retrieval routines -*- lexical-binding:t -*-
3 ;; Copyright (C) 1999, 2001, 2004-2018 Free Software Foundation, Inc.
5 ;; Author: Bill Perry <wmperry@gnu.org>
6 ;; Maintainer: emacs-devel@gnu.org
7 ;; Keywords: comm, data, processes
9 ;; This file is part of GNU Emacs.
10 ;;
11 ;; GNU Emacs is free software: you can redistribute it and/or modify
12 ;; it under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation, either version 3 of the License, or
14 ;; (at your option) any later version.
16 ;; GNU Emacs is distributed in the hope that it will be useful,
17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 ;; GNU General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>.
24 ;;; Commentary:
26 ;;; Code:
79 "What version of HTTP we advertise, as a string.
80 Valid values are 1.1 and 1.0.
81 This is only useful when debugging the HTTP subsystem.
83 Setting this to 1.0 will tell servers not to send chunked encoding,
87 "Whether to use a single TCP connection multiple times in HTTP.
88 This is only useful when debugging the HTTP subsystem. Setting to
89 nil will explicitly close the connection to the server after every
144 ;(eval-when-compile
145 ;; These are all macros so that they are hidden from external sight
146 ;; when the file is byte-compiled.
147 ;;
148 ;; This allows us to expose just the entry points we want.
150 ;; These routines will allow us to implement persistent HTTP
151 ;; connections.
155 ;; The user hit C-g, honor it! Some things can get in an
156 ;; incredibly tight loop (chunked encoding)
169 url-http-open-connections)
170 proc)
180 url-http-open-connections))
181 nil)
202 ;; `url-open-stream' needs a buffer in which to do things
203 ;; like authentication. But we use another buffer afterwards.
208 host)
211 port)
212 gateway-method)))
213 ;; url-open-stream might return nil.
215 ;; Drop the temp buffer link before killing the buffer.
218 ;; If there was an error on connect, make sure we don't
219 ;; get queried.
228 "Compute a default User-Agent string based on `url-privacy-level'."
239 emacs-info os-info))
243 (url-http-debug "getting referer from buffer: buffer:%S target-url:%S lastloc:%S" (current-buffer) url url-current-lastloc)
253 ;; url-privacy-level allows referer. But url-lastloc-privacy-level
254 ;; may restrict who we send it to.
260 referer-string)))
265 url-domain
267 referer-string)))
269 referer-string)))))))
271 ;; Building an HTTP request
273 "Compute a User-Agent string.
274 The string is based on `url-privacy-level' and `url-user-agent'."
288 "Create an HTTP request for `url-http-target-url', using `url-http-referer'
289 as the Referer-header (subject to `url-privacy-level'."
295 url-http-extra-headers))
297 nil
304 nil
307 proxy-info)
318 ;; Protection against stupid values in the referrer
323 ;; url-http-extra-headers contains an assoc-list of
324 ;; header/value pairs that we need to put into the request.
332 ;; This was done with a call to `format'. Concatenating parts has
333 ;; the advantage of keeping the parts of each header together and
334 ;; allows us to elide null lines directly, at the cost of making
335 ;; the layout less clear.
338 ;; The request
343 ;; Version of MIME we speak
345 ;; (maybe) Try to keep the connection open
349 ;; HTTP extensions we support
353 ;; Who we want to talk to
361 ;; Who its from
365 ;; Encodings we understand
367 ;; MS-Windows loads zlib dynamically, so recheck
368 ;; in case they made it available since
369 ;; initialization in url-vars.el.
378 "Accept-charset: "
381 ;; Languages we understand
385 ;; Types we understand
387 ;; User agent
389 ;; Proxy Authorization
390 proxy-auth
391 ;; Authorization
392 auth
393 ;; Cookies
397 host real-fname
399 ;; If-modified-since
406 ;; Whence we came
409 extra-headers
410 ;; Length of data
416 ;; End request
418 ;; Any data
419 url-http-data))
420 ;; Bug#23750
425 request))
430 s))
432 ;; Parsing routines
435 This allows us to use `mail-fetch-field', etc.
436 Return the number of characters removed."
448 nil nil t))
454 url-http-proxy
455 url-current-object)))
457 ;; Cheating, but who cares? :)
458 'url-http-proxy-basic-auth-storage
460 auth
463 ;; find strongest supported auth
467 this-auth)))
471 this-auth)))
476 type this-type
477 strength this-strength))))
484 " authentication. If you'd like to write it,"
486 ;; We used to set a `status' var (declared "special") but I can't
487 ;; find the corresponding let-binding, so it's probably an error.
488 ;; FIXME: Maybe it was supposed to set `success', i.e. to return t?
489 ;; (setq status t)
495 type t args)))
497 t ;Success.
499 url-http-extra-headers)
504 url-callback-arguments))
508 "Parse just the response code."
523 "Handle all set-cookie / set-cookie2 headers in an HTTP response.
524 The buffer must already be narrowed to the headers, so `mail-fetch-field' will
525 work correctly."
532 ;;; (while cookies2
533 ;;; (url-cookie-handle-set-cookie2 (pop cookies)))
534 )
535 )
541 "Parse and handle HTTP specific headers.
542 Return t if and only if the current buffer is still active and
543 should be shown to the user."
544 ;; The comments after each status code handled are taken from RFC
545 ;; 2616 (HTTP/1.1)
548 url-http-process)
549 ;; Pass the https certificate on to the caller.
564 ;;(narrow-to-region (point-min) url-http-end-of-headers)
566 ;; In HTTP 1.0, keep the connection only if there is a
567 ;; "Connection: keep-alive" header.
568 ;; In HTTP 1.1 (and greater), keep the connection unless there is a
569 ;; "Connection: close" header
582 ;; other status symbols: jewelry and luxury cars
585 class url-http-response-status)
590 ;; Classes of response codes
591 ;;
592 ;; 5xx = Server Error
593 ;; 4xx = Client Error
594 ;; 3xx = Redirection
595 ;; 2xx = Successful
596 ;; 1xx = Informational
598 ;; 100 = Continue with request
599 ;; 101 = Switching protocols
600 ;; 102 = Processing (Added by DAV)
603 url-http-response-status))
605 ;; 200 Ok
606 ;; 201 Created
607 ;; 202 Accepted
608 ;; 203 Non-authoritative information
609 ;; 204 No content
610 ;; 205 Reset content
611 ;; 206 Partial content
612 ;; 207 Multi-status (Added by DAV)
615 ;; No new data, just stay at the same document
618 ;; Generic success for all others. Store in the cache, and
619 ;; mark it as successful.
625 ;; 300 Multiple choices
626 ;; 301 Moved permanently
627 ;; 302 Found
628 ;; 303 See other
629 ;; 304 Not modified
630 ;; 305 Use proxy
631 ;; 307 Temporary redirect
636 ;; Quoth the spec (section 10.3.1)
637 ;; -------------------------------
638 ;; The requested resource corresponds to any one of a set of
639 ;; representations, each with its own specific location and
640 ;; agent-driven negotiation information is being provided so
641 ;; that the user can select a preferred representation and
642 ;; redirect its request to that location.
643 ;; [...]
644 ;; If the server has a preferred choice of representation, it
645 ;; SHOULD include the specific URI for that representation in
646 ;; the Location field; user agents MAY use the Location field
647 ;; value for automatic redirection.
648 ;; -------------------------------
649 ;; We do not support agent-driven negotiation, so we just
650 ;; redirect to the preferred URI if one is provided.
651 nil)
653 ;; 302 Found was ambiguously defined in the standards, but
654 ;; it's now recommended that it's treated like 303 instead
655 ;; of 307, since that's what most servers expect.
657 url-http-data nil))
659 ;; The response to the request can be found under a different
660 ;; URI and SHOULD be retrieved using a GET method on that
661 ;; resource.
663 url-http-data nil))
665 ;; The 304 response MUST NOT contain a message-body.
670 success t))
672 ;; The requested resource MUST be accessed through the
673 ;; proxy given by the Location field. The Location field
674 ;; gives the URI of the proxy. The recipient is expected
675 ;; to repeat this single request via the proxy. 305
676 ;; responses MUST only be generated by origin servers.
678 redirect-uri))
680 ;; Treat everything like '300'
681 nil))
683 ;; Clean off any whitespace and/or <...> cruft.
689 ;; Some stupid sites (like sourceforge) send a
690 ;; non-fully-qualified URL (ie: /), which royally confuses
691 ;; the URL library.
693 ;; Be careful to use the real target URL, otherwise we may
694 ;; compute the redirection relative to the URL of the proxy.
697 ;; Do not automatically include an authorization header in the
698 ;; redirect. If needed it will be regenerated by the relevant
699 ;; auth scheme when the new request happens.
706 ;; Check existing number of redirects
717 ;; url-max-redirections hasn't been reached, so go
718 ;; ahead and redirect.
720 ;; Remember that the request was redirected.
724 ;; Put in the current buffer a forwarding pointer to the new
725 ;; destination buffer.
726 ;; FIXME: This is a hack to fix url-retrieve-synchronously
727 ;; without changing the API. Instead url-retrieve should
728 ;; either simply not return the "destination" buffer, or it
729 ;; should take an optional `dest-buf' argument.
732 redirect-uri url-callback-function
733 url-callback-arguments
737 ;; We hit url-max-redirections, so issue an error and
738 ;; stop redirecting.
742 redirect-uri))
746 ;; 400 Bad Request
747 ;; 401 Unauthorized
748 ;; 402 Payment required
749 ;; 403 Forbidden
750 ;; 404 Not found
751 ;; 405 Method not allowed
752 ;; 406 Not acceptable
753 ;; 407 Proxy authentication required
754 ;; 408 Request time-out
755 ;; 409 Conflict
756 ;; 410 Gone
757 ;; 411 Length required
758 ;; 412 Precondition failed
759 ;; 413 Request entity too large
760 ;; 414 Request-URI too large
761 ;; 415 Unsupported media type
762 ;; 416 Requested range not satisfiable
763 ;; 417 Expectation failed
764 ;; 422 Unprocessable Entity (Added by DAV)
765 ;; 423 Locked
766 ;; 424 Failed Dependency
770 ;; The request requires user authentication. The response
771 ;; MUST include a WWW-Authenticate header field containing a
772 ;; challenge applicable to the requested resource. The
773 ;; client MAY repeat the request with a suitable
774 ;; Authorization header field.
777 ;; This code is reserved for future use
781 ;; The server understood the request, but is refusing to
782 ;; fulfill it. Authorization will not help and the request
783 ;; SHOULD NOT be repeated.
784 t)
786 ;; Not found
787 t)
789 ;; The method specified in the Request-Line is not allowed
790 ;; for the resource identified by the Request-URI. The
791 ;; response MUST include an Allow header containing a list of
792 ;; valid methods for the requested resource.
793 t)
795 ;; The resource identified by the request is only capable of
796 ;; generating response entities which have content
797 ;; characteristics not acceptable according to the accept
798 ;; headers sent in the request.
799 t)
801 ;; This code is similar to 401 (Unauthorized), but indicates
802 ;; that the client must first authenticate itself with the
803 ;; proxy. The proxy MUST return a Proxy-Authenticate header
804 ;; field containing a challenge applicable to the proxy for
805 ;; the requested resource.
808 ;; The client did not produce a request within the time that
809 ;; the server was prepared to wait. The client MAY repeat
810 ;; the request without modifications at any later time.
811 t)
813 ;; The request could not be completed due to a conflict with
814 ;; the current state of the resource. This code is only
815 ;; allowed in situations where it is expected that the user
816 ;; might be able to resolve the conflict and resubmit the
817 ;; request. The response body SHOULD include enough
818 ;; information for the user to recognize the source of the
819 ;; conflict.
820 t)
822 ;; The requested resource is no longer available at the
823 ;; server and no forwarding address is known.
824 t)
826 ;; The server refuses to accept the request without a defined
827 ;; Content-Length. The client MAY repeat the request if it
828 ;; adds a valid Content-Length header field containing the
829 ;; length of the message-body in the request message.
830 ;;
831 ;; NOTE - this will never happen because
832 ;; `url-http-create-request' automatically calculates the
833 ;; content-length.
834 t)
836 ;; The precondition given in one or more of the
837 ;; request-header fields evaluated to false when it was
838 ;; tested on the server.
839 t)
841 ;; The server is refusing to process a request because the
842 ;; request entity|URI is larger than the server is willing or
843 ;; able to process.
844 t)
846 ;; The server is refusing to service the request because the
847 ;; entity of the request is in a format not supported by the
848 ;; requested resource for the requested method.
849 t)
851 ;; A server SHOULD return a response with this status code if
852 ;; a request included a Range request-header field, and none
853 ;; of the range-specifier values in this field overlap the
854 ;; current extent of the selected resource, and the request
855 ;; did not include an If-Range request-header field.
856 t)
858 ;; The expectation given in an Expect request-header field
859 ;; could not be met by this server, or, if the server is a
860 ;; proxy, the server has unambiguous evidence that the
861 ;; request could not be met by the next-hop server.
862 t)
864 ;; The request could not be understood by the server due to
865 ;; malformed syntax. The client SHOULD NOT repeat the
866 ;; request without modifications.
867 t)))
868 ;; Tell the callback that an error occurred, and what the
869 ;; status code was.
875 ;; 500 Internal server error
876 ;; 501 Not implemented
877 ;; 502 Bad gateway
878 ;; 503 Service unavailable
879 ;; 504 Gateway time-out
880 ;; 505 HTTP version not supported
881 ;; 507 Insufficient storage
885 ;; The server does not support the functionality required to
886 ;; fulfill the request.
887 nil)
889 ;; The server, while acting as a gateway or proxy, received
890 ;; an invalid response from the upstream server it accessed
891 ;; in attempting to fulfill the request.
892 nil)
894 ;; The server is currently unable to handle the request due
895 ;; to a temporary overloading or maintenance of the server.
896 ;; The implication is that this is a temporary condition
897 ;; which will be alleviated after some delay. If known, the
898 ;; length of the delay MAY be indicated in a Retry-After
899 ;; header. If no Retry-After is given, the client SHOULD
900 ;; handle the response as it would for a 500 response.
901 nil)
903 ;; The server, while acting as a gateway or proxy, did not
904 ;; receive a timely response from the upstream server
905 ;; specified by the URI (e.g. HTTP, FTP, LDAP) or some other
906 ;; auxiliary server (e.g. DNS) it needed to access in
907 ;; attempting to complete the request.
908 nil)
910 ;; The server does not support, or refuses to support, the
911 ;; HTTP protocol version that was used in the request
912 ;; message.
913 nil)
915 ;; The method could not be performed on the resource
916 ;; because the server is unable to store the representation
917 ;; needed to successfully complete the request. This
918 ;; condition is considered to be temporary. If the request
919 ;; which received this status code was the result of a user
920 ;; action, the request MUST NOT be repeated until it is
921 ;; requested by a separate user action.
922 nil))
923 ;; Tell the callback that an error occurred, and what the
924 ;; status code was.
931 class url-http-response-status)))
938 success))
954 ;; Miscellaneous
956 "Activate callback specified when this buffer was created."
959 url-http-process)
964 ;; )
966 ;; These unfortunately cannot be macros... please ignore them!
968 "Remove (now defunct) process PROC from the list of open connections."
972 url-http-open-connections))
975 ;; Sentinel used to handle (i) terminated old HTTP/0.9 connections,
976 ;; and (ii) closed connection due to reusing a HTTP connection which
977 ;; we believed was still alive, but which the server closed on us.
978 ;; We handle case (ii) by calling `url-http' again.
987 ;; HTTP/0.9 just gets passed back no matter what
989 ;; Call `url-http' again if our connection expired.
995 url-current-object
1006 ;; Function used when we do NOT know how long the document is going to be
1007 ;; Just _very_ simple 'downloaded %d' type of info.
1011 "Function used when we DO know how long the document is going to be.
1012 More sophisticated percentage downloaded, etc.
1013 Also does minimal parsing of HTTP headers and will actually cause
1014 the callback to be triggered."
1017 "Reading [%s]... %s of %s (%d%%)"
1019 url-http-content-length)
1020 url-http-content-type
1024 url-http-content-length))
1026 "Reading... %s of %s (%d%%)"
1028 url-http-content-length)
1032 url-http-content-length)))
1036 ;; Found the end of the document! Wheee!
1043 "Function used when dealing with chunked encoding.
1044 Cannot give a sophisticated percentage, but we need a different
1045 function to look for the special 0-length chunk that signifies
1046 the end of the document."
1053 ;; We need to loop thru looking for more chunks even within
1054 ;; one after-change-function call.
1059 "Reading [%s]... chunk #%d"
1060 url-http-content-type url-http-chunked-counter)
1062 "Reading... chunk #%d"
1063 url-http-chunked-counter))
1065 url-http-chunked-counter st nd length)
1071 ;; We know how long the chunk is supposed to be, skip over
1072 ;; leading crap if possible.
1076 url-http-chunked-counter)
1078 url-http-chunked-length)))
1081 url-http-chunked-length)
1082 nd))
1089 ;; Must not have received the entirety of the chunk header,
1090 ;; need to spin some more.
1095 'end-open t
1096 'chunked-encoding t
1108 ; (if (not url-http-debug)
1111 url-http-chunked-counter url-http-chunked-length
1115 ;; Found the end of the document! Wheee!
1119 ;; Every chunk, even the last 0-length one, is
1120 ;; terminated by CRLF. Skip it.
1130 ;; This will wait for the headers to arrive and then splice in the
1131 ;; next appropriate after-change-function, etc.
1137 ;; (content-length nil)
1138 )
1143 ;; Not HTTP/x.y data, must be 0.9
1144 ;; God, I wish this could die.
1146 url-http-end-of-headers 0
1147 old-http t)
1148 ;; Blank line at end of headers.
1151 ;; Saw the end of the headers
1155 end-of-headers t)
1159 ;; Haven't seen the end of the headers yet, need to wait
1160 ;; for more data to arrive.
1161 nil
1178 ;; We got back a headerless malformed response from the
1179 ;; server.
1188 ;; A HEAD request is _ALWAYS_ terminated by the header
1189 ;; information, regardless of any entity headers,
1190 ;; according to section 4.4 of the HTTP/1.1 draft.
1196 ;; A CONNECT request is finished, but we cannot stick this
1197 ;; back on the free connection list
1202 ;; Only allowed to have a header section. We have to handle
1203 ;; this here instead of in url-http-parse-headers because if
1204 ;; you have a cached copy of something without a known
1205 ;; content-length, and try to retrieve it from the cache, we'd
1206 ;; fall into the 'being dumb' section and wait for the
1207 ;; connection to terminate, which means we'd wait for 10
1208 ;; seconds for the keep-alives to time out on some servers.
1212 ;; HTTP/0.9 always signaled end-of-connection by closing the
1213 ;; connection.
1235 ;; We got a NULL body! Activate the callback
1236 ;; immediately!
1242 ;; Have some leftover data
1246 nd
1249 nil)))
1254 ;; We are still at the beginning of the buffer... must just be
1255 ;; waiting for a response.
1261 "Retrieve URL via HTTP asynchronously.
1262 URL must be a parsed URL. See `url-generic-parse-url' for details.
1264 When retrieval is completed, execute the function CALLBACK,
1265 passing it an updated value of CBARGS as arguments. The first
1266 element in CBARGS should be a plist describing what has happened
1267 so far during the request, as described in the docstring of
1268 `url-retrieve' (if in doubt, specify nil). The current buffer
1269 then CALLBACK is executed is the retrieval buffer.
1271 Optional arg RETRY-BUFFER, if non-nil, specifies the buffer of a
1272 previous `url-http' call, which is being re-attempted.
1274 Optional arg GATEWAY-METHOD specifies the gateway to be used,
1275 overriding the value of `url-gateway-method'.
1277 The return value of this function is the retrieval buffer."
1280 ;; (port (url-port (or url-using-proxy url)))
1283 url-http-noninteractive)))
1284 ;; The following binding is needed in url-open-stream, which
1285 ;; is called from url-http-find-free-connection.
1289 gateway-method))
1296 ;; Failed to open the connection for some reason
1308 url-http-content-type
1309 url-http-content-length
1310 url-http-transfer-encoding
1311 url-http-after-change-function
1312 url-http-response-version
1313 url-http-response-status
1314 url-http-chunked-length
1315 url-http-chunked-counter
1316 url-http-chunked-start
1317 url-callback-function
1318 url-callback-arguments
1319 url-show-status
1320 url-http-process
1321 url-http-method
1322 url-http-extra-headers
1323 url-http-noninteractive
1324 url-http-data
1325 url-http-target-url
1326 url-http-no-retry
1327 url-http-connection-opened
1328 url-mime-accept-string
1329 url-http-proxy
1330 url-http-referer))
1334 url-http-extra-headers url-request-extra-headers
1335 url-http-noninteractive url-request-noninteractive
1336 url-http-data url-request-data
1337 url-http-process connection
1338 url-http-chunked-length nil
1339 url-http-chunked-start nil
1340 url-http-chunked-counter 0
1341 url-callback-function callback
1342 url-callback-arguments cbargs
1343 url-http-after-change-function 'url-http-wait-for-headers-change-function
1344 url-http-target-url url-current-object
1345 url-http-no-retry retry-buffer
1346 url-http-connection-opened nil
1347 url-mime-accept-string mime-accept-string
1348 url-http-proxy url-using-proxy
1349 url-http-referer referer)
1354 (`connect
1355 ;; Asynchronous connection
1357 (`failed
1358 ;; Asynchronous connection failed
1368 buffer))
1377 url-https-default-port)
1386 ;; Saw the end of the headers
1391 ;; We got back a headerless malformed response from the
1392 ;; server.
1399 :process proc
1402 ;; check certificate validity
1426 ;; We are performing an asynchronous connection, and a status change
1427 ;; has occurred.
1451 ;; Since Emacs 19/20 does not allow you to change the
1452 ;; `after-change-functions' hook in the midst of running them, we fake
1453 ;; an after change by hooking into the process filter and inserting
1454 ;; the data ourselves. This is slightly less efficient, but there
1455 ;; were tons of weird ways the after-change code was biting us in the
1456 ;; shorts.
1457 ;; FIXME this can probably be simplified since the above is no longer true.
1459 ;; Sometimes we get a zero-length data chunk after the process has
1460 ;; been changed to 'free', which means it has no buffer associated
1461 ;; with it. Do nothing if there is no buffer, or 0 length data.
1465 (url-http-debug "Calling after change function `%s' for `%S'" url-http-after-change-function proc)
1474 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
1475 ;;; file-name-handler stuff from here on out
1476 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
1479 'symbol-value-in-buffer
1481 "Return the value of SYMBOL in BUFFER, or UNBOUND-VALUE if it is unbound."
1484 unbound-value
1509 nil ;dir / link / normal file
1512 nil nil nil ;atime ; mtime ; ctime
1527 "Return a property list describing options available for URL.
1528 This list is retrieved using the `OPTIONS' HTTP method.
1530 Property list members:
1532 methods
1533 A list of symbols specifying what HTTP methods the resource
1534 supports.
1536 dav
1537 A list of numbers specifying what DAV protocol/schema versions are
1538 supported.
1540 dasl
1541 A list of supported DASL search types supported (string form)
1543 ranges
1544 A list of the units available for use in partial document fetches.
1546 p3p
1547 The `Platform For Privacy Protection' description for the resource.
1548 Currently this is just the raw header contents. This is likely to
1549 change once P3P is formally supported by the URL package or
1550 Emacs/W3."
1558 ;; Only parse the options if we got a 2xx response code!
1564 ;; Figure out what methods are supported.
1567 options 'methods
1570 ;; Check for DAV
1573 options 'dav
1578 ;; Now for DASL
1581 options 'dasl
1584 ;; P3P - should get more detailed here. FIXME
1588 ;; Check for whether they accept byte-range requests.
1591 options 'ranges
1595 ))))
1597 options))
1599 ;; HTTPS. This used to be in url-https.el, but that file collides
1600 ;; with url-http.el on systems with 8-character file names.
1605 ;; FIXME what is the point of this alias being an autoload?
1606 ;; Trying to use it will not cause url-http to be loaded,
1607 ;; since the full alias just gets dumped into loaddefs.el.
1609 ;;;###autoload (autoload 'url-default-expander "url-expand")
1610 ;;;###autoload
1619 ;;;###autoload (autoload 'url-https "url-http")
1621 ;;;###autoload (autoload 'url-https-file-exists-p "url-http")
1623 ;;;###autoload (autoload 'url-https-file-readable-p "url-http")
1625 ;;;###autoload (autoload 'url-https-file-attributes "url-http")
1630 ;;; url-http.el ends here