init repo.

third_party/curl/lib/pingpong.h

@@ -0,0 +1,160 @@
+#ifndef HEADER_CURL_PINGPONG_H
+#define HEADER_CURL_PINGPONG_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"
+
+#if !defined(CURL_DISABLE_IMAP) || !defined(CURL_DISABLE_FTP) || \
+  !defined(CURL_DISABLE_POP3) || !defined(CURL_DISABLE_SMTP)
+#define USE_PINGPONG
+#endif
+
+/* forward-declaration, this is defined in urldata.h */
+struct connectdata;
+
+typedef enum {
+  PPTRANSFER_BODY, /* yes do transfer a body */
+  PPTRANSFER_INFO, /* do still go through to get info/headers */
+  PPTRANSFER_NONE  /* don't get anything and don't get info */
+} curl_pp_transfer;
+
+/*
+ * 'pingpong' is the generic struct used for protocols doing server<->client
+ * conversations in a back-and-forth style such as FTP, IMAP, POP3, SMTP etc.
+ *
+ * It holds response cache and non-blocking sending data.
+ */
+struct pingpong {
+  size_t nread_resp;  /* number of bytes currently read of a server response */
+  bool pending_resp;  /* set TRUE when a server response is pending or in
+                         progress, and is cleared once the last response is
+                         read */
+  char *sendthis; /* pointer to a buffer that is to be sent to the server */
+  size_t sendleft; /* number of bytes left to send from the sendthis buffer */
+  size_t sendsize; /* total size of the sendthis buffer */
+  struct curltime response; /* set to Curl_now() when a command has been sent
+                               off, used to time-out response reading */
+  timediff_t response_time; /* When no timeout is given, this is the amount of
+                               milliseconds we await for a server response. */
+  struct dynbuf sendbuf;
+  struct dynbuf recvbuf;
+  size_t overflow; /* number of bytes left after a final response line */
+  size_t nfinal;   /* number of bytes in the final response line, which
+                      after a match is first in the receice buffer */
+
+  /* Function pointers the protocols MUST implement and provide for the
+     pingpong layer to function */
+
+  CURLcode (*statemachine)(struct Curl_easy *data, struct connectdata *conn);
+  bool (*endofresp)(struct Curl_easy *data, struct connectdata *conn,
+                    char *ptr, size_t len, int *code);
+};
+
+#define PINGPONG_SETUP(pp,s,e)                   \
+  do {                                           \
+    pp->response_time = RESP_TIMEOUT;            \
+    pp->statemachine = s;                        \
+    pp->endofresp = e;                           \
+  } while(0)
+
+/*
+ * Curl_pp_statemach()
+ *
+ * called repeatedly until done. Set 'wait' to make it wait a while on the
+ * socket if there's no traffic.
+ */
+CURLcode Curl_pp_statemach(struct Curl_easy *data, struct pingpong *pp,
+                           bool block, bool disconnecting);
+
+/* initialize stuff to prepare for reading a fresh new response */
+void Curl_pp_init(struct pingpong *pp);
+
+/* Returns timeout in ms. 0 or negative number means the timeout has already
+   triggered */
+timediff_t Curl_pp_state_timeout(struct Curl_easy *data,
+                                 struct pingpong *pp, bool disconnecting);
+
+
+/***********************************************************************
+ *
+ * Curl_pp_sendf()
+ *
+ * Send the formatted string as a command to a pingpong server. Note that
+ * the string should not have any CRLF appended, as this function will
+ * append the necessary things itself.
+ *
+ * made to never block
+ */
+CURLcode Curl_pp_sendf(struct Curl_easy *data,
+                       struct pingpong *pp,
+                       const char *fmt, ...) CURL_PRINTF(3, 4);
+
+/***********************************************************************
+ *
+ * Curl_pp_vsendf()
+ *
+ * Send the formatted string as a command to a pingpong server. Note that
+ * the string should not have any CRLF appended, as this function will
+ * append the necessary things itself.
+ *
+ * made to never block
+ */
+CURLcode Curl_pp_vsendf(struct Curl_easy *data,
+                        struct pingpong *pp,
+                        const char *fmt,
+                        va_list args) CURL_PRINTF(3, 0);
+
+/*
+ * Curl_pp_readresp()
+ *
+ * Reads a piece of a server response.
+ */
+CURLcode Curl_pp_readresp(struct Curl_easy *data,
+                          int sockindex,
+                          struct pingpong *pp,
+                          int *code, /* return the server code if done */
+                          size_t *size); /* size of the response */
+
+
+CURLcode Curl_pp_flushsend(struct Curl_easy *data,
+                           struct pingpong *pp);
+
+/* call this when a pingpong connection is disconnected */
+CURLcode Curl_pp_disconnect(struct pingpong *pp);
+
+int Curl_pp_getsock(struct Curl_easy *data, struct pingpong *pp,
+                    curl_socket_t *socks);
+
+
+/***********************************************************************
+ *
+ * Curl_pp_moredata()
+ *
+ * Returns whether there are still more data in the cache and so a call
+ * to Curl_pp_readresp() will not block.
+ */
+bool Curl_pp_moredata(struct pingpong *pp);
+
+#endif /* HEADER_CURL_PINGPONG_H */