curl/lib/socks.h
Stefan Eissing 5651a36d1a
cf-socket: improvements in socket I/O handling
- Curl_write_plain/Curl_read_plain have been eliminated. Last code use
  now uses Curl_conn_send/recv so that requests use conn->send/revc
  callbacks which defaults to cfilters use.
- Curl_recv_plain/Curl_send_plain have been internalized in cf-socket.c.
- USE_RECV_BEFORE_SEND_WORKAROUND (active on Windows) has been moved
  into cf-socket.c. The pre_recv buffer is held at the socket filter
  context.  `postponed_data` structures have been removed from
  `connectdata`.
- the hanger in HTTP/2 request handling was a result of read buffering
  on all sends and the multi handling is not prepared for this. The
  following happens:

   - multi preforms on a HTTP/2 easy handle
   - h2 reads and processes data
   - this leads to a send of h2 data
   - which receives and buffers before the send
   - h2 returns
   - multi selects on the socket, but no data arrives (its in the buffer already)
   the workaround now receives data in a loop as long as there is something in
   the buffer. The real fix would be for multi to change, so that `data_pending`
   is evaluated before deciding to wait on the socket.

io_buffer, optional, in cf-socket.c, http/2 sets state.drain if lower
filter have pending data.

This io_buffer is only available/used when the
-DUSE_RECV_BEFORE_SEND_WORKAROUND is active, e.g. on Windows
configurations. It also maintains the original checks on protocol
handler being HTTP and conn->send/recv not being replaced.

The HTTP/2 (nghttp2) cfilter now sets data->state.drain when it finds
out that the "lower" filter chain has still pending data at the end of
its IO operation. This prevents the processing from becoming stalled.

Closes #10280
2023-01-31 11:23:59 +01:00

66 lines
2.3 KiB
C

#ifndef HEADER_CURL_SOCKS_H
#define HEADER_CURL_SOCKS_H
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
#include "curl_setup.h"
#ifdef CURL_DISABLE_PROXY
#define Curl_SOCKS4(a,b,c,d,e) CURLE_NOT_BUILT_IN
#define Curl_SOCKS5(a,b,c,d,e,f) CURLE_NOT_BUILT_IN
#define Curl_SOCKS_getsock(x,y,z) 0
#else
/*
* Helper read-from-socket functions. Does the same as Curl_read() but it
* blocks until all bytes amount of buffersize will be read. No more, no less.
*
* This is STUPID BLOCKING behavior
*/
int Curl_blockread_all(struct Curl_cfilter *cf,
struct Curl_easy *data,
char *buf,
ssize_t buffersize,
ssize_t *n);
#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
/*
* This function handles the SOCKS5 GSS-API negotiation and initialization
*/
CURLcode Curl_SOCKS5_gssapi_negotiate(struct Curl_cfilter *cf,
struct Curl_easy *data);
#endif
CURLcode Curl_conn_socks_proxy_add(struct Curl_easy *data,
struct connectdata *conn,
int sockindex);
CURLcode Curl_cf_socks_proxy_insert_after(struct Curl_cfilter *cf_at,
struct Curl_easy *data);
extern struct Curl_cftype Curl_cft_socks_proxy;
#endif /* CURL_DISABLE_PROXY */
#endif /* HEADER_CURL_SOCKS_H */