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 */ 35 struct connectdata; 36 37 typedef enum { 38 PPTRANSFER_BODY, /* yes do transfer a body */ 39 PPTRANSFER_INFO, /* do still go through to get info/headers */ 40 PPTRANSFER_NONE /* do not get anything and do not 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 */ 49 struct pingpong { 50 size_t nread_resp; /* number of bytes currently read of a server response */ 51 bool pending_resp; /* set TRUE when a server response is pending or in 52 progress, and is cleared once the last response is 53 read */ 54 char *sendthis; /* pointer to a buffer that is to be sent to the server */ 55 size_t sendleft; /* number of bytes left to send from the sendthis buffer */ 56 size_t sendsize; /* total size of the sendthis buffer */ 57 struct curltime response; /* set to Curl_now() when a command has been sent 58 off, used to time-out response reading */ 59 timediff_t response_time; /* When no timeout is given, this is the amount of 60 milliseconds we await for a server response. */ 61 struct dynbuf sendbuf; 62 struct dynbuf recvbuf; 63 size_t overflow; /* number of bytes left after a final response line */ 64 size_t nfinal; /* number of bytes in the final response line, which 65 after a match is first in the receice buffer */ 66 67 /* Function pointers the protocols MUST implement and provide for the 68 pingpong layer to function */ 69 70 CURLcode (*statemachine)(struct Curl_easy *data, struct connectdata *conn); 71 bool (*endofresp)(struct Curl_easy *data, struct connectdata *conn, 72 char *ptr, size_t len, int *code); 73 }; 74 75 #define PINGPONG_SETUP(pp,s,e) \ 76 do { \ 77 pp->response_time = RESP_TIMEOUT; \ 78 pp->statemachine = s; \ 79 pp->endofresp = e; \ 80 } while(0) 81 82 /* 83 * Curl_pp_statemach() 84 * 85 * called repeatedly until done. Set 'wait' to make it wait a while on the 86 * socket if there is no traffic. 87 */ 88 CURLcode Curl_pp_statemach(struct Curl_easy *data, struct pingpong *pp, 89 bool block, bool disconnecting); 90 91 /* initialize stuff to prepare for reading a fresh new response */ 92 void Curl_pp_init(struct pingpong *pp); 93 94 /* Returns timeout in ms. 0 or negative number means the timeout has already 95 triggered */ 96 timediff_t Curl_pp_state_timeout(struct Curl_easy *data, 97 struct pingpong *pp, bool disconnecting); 98 99 100 /*********************************************************************** 101 * 102 * Curl_pp_sendf() 103 * 104 * Send the formatted string as a command to a pingpong server. Note that 105 * the string should not have any CRLF appended, as this function will 106 * append the necessary things itself. 107 * 108 * made to never block 109 */ 110 CURLcode Curl_pp_sendf(struct Curl_easy *data, 111 struct pingpong *pp, 112 const char *fmt, ...) CURL_PRINTF(3, 4); 113 114 /*********************************************************************** 115 * 116 * Curl_pp_vsendf() 117 * 118 * Send the formatted string as a command to a pingpong server. Note that 119 * the string should not have any CRLF appended, as this function will 120 * append the necessary things itself. 121 * 122 * made to never block 123 */ 124 CURLcode Curl_pp_vsendf(struct Curl_easy *data, 125 struct pingpong *pp, 126 const char *fmt, 127 va_list args) CURL_PRINTF(3, 0); 128 129 /* 130 * Curl_pp_readresp() 131 * 132 * Reads a piece of a server response. 133 */ 134 CURLcode Curl_pp_readresp(struct Curl_easy *data, 135 int sockindex, 136 struct pingpong *pp, 137 int *code, /* return the server code if done */ 138 size_t *size); /* size of the response */ 139 140 bool Curl_pp_needs_flush(struct Curl_easy *data, 141 struct pingpong *pp); 142 143 CURLcode Curl_pp_flushsend(struct Curl_easy *data, 144 struct pingpong *pp); 145 146 /* call this when a pingpong connection is disconnected */ 147 CURLcode Curl_pp_disconnect(struct pingpong *pp); 148 149 int Curl_pp_getsock(struct Curl_easy *data, struct pingpong *pp, 150 curl_socket_t *socks); 151 152 153 /*********************************************************************** 154 * 155 * Curl_pp_moredata() 156 * 157 * Returns whether there are still more data in the cache and so a call 158 * to Curl_pp_readresp() will not block. 159 */ 160 bool Curl_pp_moredata(struct pingpong *pp); 161 162 #endif /* HEADER_CURL_PINGPONG_H */ 163
