1 #ifndef HEADER_CURL_PINGPONG_H 2 #define HEADER_CURL_PINGPONG_H 3 /*************************************************************************** 4 * _ _ ____ _ 5 * Project ___| | | | _ \| | 6 * / __| | | | |_) | | 7 * | (__| |_| | _ <| |___ 8 * \___|\___/|_| \_\_____| 9 * 10 * Copyright (C) 1998 - 2021, 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 ***************************************************************************/ 24 25 #include "curl_setup.h" 26 27 #if !defined(CURL_DISABLE_IMAP) || !defined(CURL_DISABLE_FTP) || \ 28 !defined(CURL_DISABLE_POP3) || !defined(CURL_DISABLE_SMTP) 29 #define USE_PINGPONG 30 #endif 31 32 /* forward-declaration, this is defined in urldata.h */ 33 struct connectdata; 34 35 typedef enum { 36 PPTRANSFER_BODY, /* yes do transfer a body */ 37 PPTRANSFER_INFO, /* do still go through to get info/headers */ 38 PPTRANSFER_NONE /* don't get anything and don't get info */ 39 } curl_pp_transfer; 40 41 /* 42 * 'pingpong' is the generic struct used for protocols doing server<->client 43 * conversations in a back-and-forth style such as FTP, IMAP, POP3, SMTP etc. 44 * 45 * It holds response cache and non-blocking sending data. 46 */ 47 struct pingpong { 48 char *cache; /* data cache between getresponse()-calls */ 49 size_t cache_size; /* size of cache in bytes */ 50 size_t nread_resp; /* number of bytes currently read of a server response */ 51 char *linestart_resp; /* line start pointer for the server response 52 reader function */ 53 bool pending_resp; /* set TRUE when a server response is pending or in 54 progress, and is cleared once the last response is 55 read */ 56 char *sendthis; /* allocated pointer to a buffer that is to be sent to the 57 server */ 58 size_t sendleft; /* number of bytes left to send from the sendthis buffer */ 59 size_t sendsize; /* total size of the sendthis buffer */ 60 struct curltime response; /* set to Curl_now() when a command has been sent 61 off, used to time-out response reading */ 62 timediff_t response_time; /* When no timeout is given, this is the amount of 63 milliseconds we await for a server response. */ 64 struct dynbuf sendbuf; 65 66 /* Function pointers the protocols MUST implement and provide for the 67 pingpong layer to function */ 68 69 CURLcode (*statemachine)(struct Curl_easy *data, struct connectdata *conn); 70 bool (*endofresp)(struct Curl_easy *data, struct connectdata *conn, 71 char *ptr, size_t len, int *code); 72 }; 73 74 #define PINGPONG_SETUP(pp,s,e) \ 75 do { \ 76 pp->response_time = RESP_TIMEOUT; \ 77 pp->statemachine = s; \ 78 pp->endofresp = e; \ 79 } while(0) 80 81 /* 82 * Curl_pp_statemach() 83 * 84 * called repeatedly until done. Set 'wait' to make it wait a while on the 85 * socket if there's no traffic. 86 */ 87 CURLcode Curl_pp_statemach(struct Curl_easy *data, struct pingpong *pp, 88 bool block, bool disconnecting); 89 90 /* initialize stuff to prepare for reading a fresh new response */ 91 void Curl_pp_init(struct Curl_easy *data, struct pingpong *pp); 92 93 /* setup for the transfer */ 94 void Curl_pp_setup(struct pingpong *pp); 95 96 /* Returns timeout in ms. 0 or negative number means the timeout has already 97 triggered */ 98 timediff_t Curl_pp_state_timeout(struct Curl_easy *data, 99 struct pingpong *pp, bool disconnecting); 100 101 102 /*********************************************************************** 103 * 104 * Curl_pp_sendf() 105 * 106 * Send the formatted string as a command to a pingpong server. Note that 107 * the string should not have any CRLF appended, as this function will 108 * append the necessary things itself. 109 * 110 * made to never block 111 */ 112 CURLcode Curl_pp_sendf(struct Curl_easy *data, 113 struct pingpong *pp, 114 const char *fmt, ...); 115 116 /*********************************************************************** 117 * 118 * Curl_pp_vsendf() 119 * 120 * Send the formatted string as a command to a pingpong server. Note that 121 * the string should not have any CRLF appended, as this function will 122 * append the necessary things itself. 123 * 124 * made to never block 125 */ 126 CURLcode Curl_pp_vsendf(struct Curl_easy *data, 127 struct pingpong *pp, 128 const char *fmt, 129 va_list args); 130 131 /* 132 * Curl_pp_readresp() 133 * 134 * Reads a piece of a server response. 135 */ 136 CURLcode Curl_pp_readresp(struct Curl_easy *data, 137 curl_socket_t sockfd, 138 struct pingpong *pp, 139 int *code, /* return the server code if done */ 140 size_t *size); /* size of the response */ 141 142 143 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