1#ifndef HEADER_CURL_PINGPONG_H
2#define HEADER_CURL_PINGPONG_H
3/***************************************************************************
4 * _ _ ____ _
5 * Project ___| | | | _ \| |
6 * / __| | | | |_) | |
7 * | (__| |_| | _ <| |___
8 * \___|\___/|_| \_\_____|
9 *
10 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
11 *
12 * This software is licensed as described in the file COPYING, which
13 * you should have received as part of this distribution. The terms
14 * are also available at https://curl.se/docs/copyright.html.
15 *
16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
17 * copies of the Software, and permit persons to whom the Software is
18 * furnished to do so, under the terms of the COPYING file.
19 *
20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
21 * KIND, either express or implied.
22 *
23 * SPDX-License-Identifier: curl
24 *
25 ***************************************************************************/
26
27#include "curl_setup.h"
28
29#if !defined(CURL_DISABLE_IMAP) || !defined(CURL_DISABLE_FTP) || \
30 !defined(CURL_DISABLE_POP3) || !defined(CURL_DISABLE_SMTP)
31#define USE_PINGPONG
32#endif
33
34/* forward-declaration, this is defined in urldata.h */
35struct connectdata;
36
37typedef enum {
38 PPTRANSFER_BODY, /* yes do transfer a body */
39 PPTRANSFER_INFO, /* do still go through to get info/headers */
40 PPTRANSFER_NONE /* don't get anything and don't get info */
41} curl_pp_transfer;
42
43/*
44 * 'pingpong' is the generic struct used for protocols doing server<->client
45 * conversations in a back-and-forth style such as FTP, IMAP, POP3, SMTP etc.
46 *
47 * It holds response cache and non-blocking sending data.
48 */
49struct pingpong {
50 char *cache; /* data cache between getresponse()-calls */
51 size_t cache_size; /* size of cache in bytes */
52 size_t nread_resp; /* number of bytes currently read of a server response */
53 char *linestart_resp; /* line start pointer for the server response
54 reader function */
55 bool pending_resp; /* set TRUE when a server response is pending or in
56 progress, and is cleared once the last response is
57 read */
58 char *sendthis; /* allocated pointer to a buffer that is to be sent to the
59 server */
60 size_t sendleft; /* number of bytes left to send from the sendthis buffer */
61 size_t sendsize; /* total size of the sendthis buffer */
62 struct curltime response; /* set to Curl_now() when a command has been sent
63 off, used to time-out response reading */
64 timediff_t response_time; /* When no timeout is given, this is the amount of
65 milliseconds we await for a server response. */
66 struct dynbuf sendbuf;
67
68 /* Function pointers the protocols MUST implement and provide for the
69 pingpong layer to function */
70
71 CURLcode (*statemachine)(struct Curl_easy *data, struct connectdata *conn);
72 bool (*endofresp)(struct Curl_easy *data, struct connectdata *conn,
73 char *ptr, size_t len, int *code);
74};
75
76#define PINGPONG_SETUP(pp,s,e) \
77 do { \
78 pp->response_time = RESP_TIMEOUT; \
79 pp->statemachine = s; \
80 pp->endofresp = e; \
81 } while(0)
82
83/*
84 * Curl_pp_statemach()
85 *
86 * called repeatedly until done. Set 'wait' to make it wait a while on the
87 * socket if there's no traffic.
88 */
89CURLcode Curl_pp_statemach(struct Curl_easy *data, struct pingpong *pp,
90 bool block, bool disconnecting);
91
92/* initialize stuff to prepare for reading a fresh new response */
93void Curl_pp_init(struct Curl_easy *data, struct pingpong *pp);
94
95/* setup for the transfer */
96void Curl_pp_setup(struct pingpong *pp);
97
98/* Returns timeout in ms. 0 or negative number means the timeout has already
99 triggered */
100timediff_t Curl_pp_state_timeout(struct Curl_easy *data,
101 struct pingpong *pp, bool disconnecting);
102
103
104/***********************************************************************
105 *
106 * Curl_pp_sendf()
107 *
108 * Send the formatted string as a command to a pingpong server. Note that
109 * the string should not have any CRLF appended, as this function will
110 * append the necessary things itself.
111 *
112 * made to never block
113 */
114CURLcode Curl_pp_sendf(struct Curl_easy *data,
115 struct pingpong *pp,
116 const char *fmt, ...);
117
118/***********************************************************************
119 *
120 * Curl_pp_vsendf()
121 *
122 * Send the formatted string as a command to a pingpong server. Note that
123 * the string should not have any CRLF appended, as this function will
124 * append the necessary things itself.
125 *
126 * made to never block
127 */
128CURLcode Curl_pp_vsendf(struct Curl_easy *data,
129 struct pingpong *pp,
130 const char *fmt,
131 va_list args);
132
133/*
134 * Curl_pp_readresp()
135 *
136 * Reads a piece of a server response.
137 */
138CURLcode Curl_pp_readresp(struct Curl_easy *data,
139 curl_socket_t sockfd,
140 struct pingpong *pp,
141 int *code, /* return the server code if done */
142 size_t *size); /* size of the response */
143
144
145CURLcode Curl_pp_flushsend(struct Curl_easy *data,
146 struct pingpong *pp);
147
148/* call this when a pingpong connection is disconnected */
149CURLcode Curl_pp_disconnect(struct pingpong *pp);
150
151int Curl_pp_getsock(struct Curl_easy *data, struct pingpong *pp,
152 curl_socket_t *socks);
153
154
155/***********************************************************************
156 *
157 * Curl_pp_moredata()
158 *
159 * Returns whether there are still more data in the cache and so a call
160 * to Curl_pp_readresp() will not block.
161 */
162bool Curl_pp_moredata(struct pingpong *pp);
163
164#endif /* HEADER_CURL_PINGPONG_H */
165