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 /* 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 */ 49 struct 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 */ 89 CURLcode 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 */ 93 void Curl_pp_init(struct Curl_easy *data, struct pingpong *pp); 94 95 /* setup for the transfer */ 96 void Curl_pp_setup(struct pingpong *pp); 97 98 /* Returns timeout in ms. 0 or negative number means the timeout has already 99 triggered */ 100 timediff_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 */ 114 CURLcode 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 */ 128 CURLcode 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 */ 138 CURLcode 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 */ 143 144 145 CURLcode Curl_pp_flushsend(struct Curl_easy *data, 146 struct pingpong *pp); 147 148 /* call this when a pingpong connection is disconnected */ 149 CURLcode Curl_pp_disconnect(struct pingpong *pp); 150 151 int 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 */ 162 bool Curl_pp_moredata(struct pingpong *pp); 163 164 #endif /* HEADER_CURL_PINGPONG_H */ 165