examples: remove asiohiper.cpp

This example has repeatedly been reported to contain bugs, and as users
copy and paste code from this into production, I now deem it better to
not provide the example at all.

Closes #5090
Closes #5322

2 files changed, 2 insertions, 498 deletions

diff --git a/docs/examples/Makefile.inc b/docs/examples/Makefile.inc
index b588b5fee..79c9e509a 100644
--- a/docs/examples/Makefile.inc
+++ b/docs/examples/Makefile.inc
@@ -5,7 +5,7 @@
 #                            | (__| |_| |  _ <| |___
 #                             \___|\___/|_| \_\_____|
 #
-# Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
+# Copyright (C) 1998 - 2020, 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
@@ -43,6 +43,6 @@ check_PROGRAMS = 10-at-a-time anyauthput cookie_interface debug fileupload \
 COMPLICATED_EXAMPLES = curlgtk.c curlx.c htmltitle.cpp cacertinmem.c \
   ghiper.c hiperfifo.c htmltidy.c multithread.c opensslthreadlock.c \
   sampleconv.c synctime.c threaded-ssl.c evhiperfifo.c \
-  smooth-gtk-thread.c version-check.pl href_extractor.c asiohiper.cpp \
+  smooth-gtk-thread.c version-check.pl href_extractor.c \
   multi-uv.c xmlstream.c usercertinmem.c sessioninfo.c \
   threaded-shared-conn.c crawler.c ephiperfifo.c multi-event.c
diff --git a/docs/examples/asiohiper.cpp b/docs/examples/asiohiper.cpp
deleted file mode 100644
index de1480507..000000000
--- a/docs/examples/asiohiper.cpp
+++ /dev/null
@@ -1,496 +0,0 @@
-/***************************************************************************
- *                                  _   _ ____  _
- *  Project                     ___| | | |  _ \| |
- *                             / __| | | | |_) | |
- *                            | (__| |_| |  _ <| |___
- *                             \___|\___/|_| \_\_____|
- *
- * Copyright (C) 2012 - 2018, 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.haxx.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.
- *
- ***************************************************************************/
-
-/* <DESC>
- * demonstrate the use of multi socket interface with boost::asio
- * </DESC>
- */
-/*
- * This program is in c++ and uses boost::asio instead of libevent/libev.
- * Requires boost::asio, boost::bind and boost::system
- *
- * This is an adaptation of libcurl's "hiperfifo.c" and "evhiperfifo.c"
- * sample programs. This example implements a subset of the functionality from
- * hiperfifo.c, for full functionality refer hiperfifo.c or evhiperfifo.c
- *
- * Written by Lijo Antony based on hiperfifo.c by Jeff Pohlmeyer
- *
- * When running, the program creates an easy handle for a URL and
- * uses the curl_multi API to fetch it.
- *
- * Note:
- *  For the sake of simplicity, URL is hard coded to "www.google.com"
- *
- * This is purely a demo app, all retrieved data is simply discarded by the
- * write callback.
- *
- * ===========================================================================
- * WARNING: This example program is known to have flaws:
- * https://github.com/curl/curl/issues/2407
- *
- * It still kept in the example repository with the hope that it might be
- * useful, and maybe some day someone who knows enough about boost::asio will
- * read this text, accept the challenge and make the example code work
- * correctly. Until then: expect this example program to fail occasionally.
- * ===========================================================================
- */
-
-
-#include <curl/curl.h>
-#include <boost/asio.hpp>
-#include <boost/bind.hpp>
-#include <iostream>
-
-#define MSG_OUT stdout /* Send info to stdout, change to stderr if you want */
-
-/* boost::asio related objects
- * using global variables for simplicity
- */
-boost::asio::io_service io_service;
-boost::asio::deadline_timer timer(io_service);
-std::map<curl_socket_t, boost::asio::ip::tcp::socket *> socket_map;
-
-/* Global information, common to all connections */
-typedef struct _GlobalInfo
-{
-  CURLM *multi;
-  int still_running;
-} GlobalInfo;
-
-/* Information associated with a specific easy handle */
-typedef struct _ConnInfo
-{
-  CURL *easy;
-  char *url;
-  GlobalInfo *global;
-  char error[CURL_ERROR_SIZE];
-} ConnInfo;
-
-static void timer_cb(const boost::system::error_code & error, GlobalInfo *g);
-
-/* Update the event timer after curl_multi library calls */
-static int multi_timer_cb(CURLM *multi, long timeout_ms, GlobalInfo *g)
-{
-  fprintf(MSG_OUT, "\nmulti_timer_cb: timeout_ms %ld", timeout_ms);
-
-  /* cancel running timer */
-  timer.cancel();
-
-  if(timeout_ms > 0) {
-    /* update timer */
-    timer.expires_from_now(boost::posix_time::millisec(timeout_ms));
-    timer.async_wait(boost::bind(&timer_cb, _1, g));
-  }
-  else if(timeout_ms == 0) {
-    /* call timeout function immediately */
-    boost::system::error_code error; /*success*/
-    timer_cb(error, g);
-  }
-
-  return 0;
-}
-
-/* Die if we get a bad CURLMcode somewhere */
-static void mcode_or_die(const char *where, CURLMcode code)
-{
-  if(CURLM_OK != code) {
-    const char *s;
-    switch(code) {
-    case CURLM_CALL_MULTI_PERFORM:
-      s = "CURLM_CALL_MULTI_PERFORM";
-      break;
-    case CURLM_BAD_HANDLE:
-      s = "CURLM_BAD_HANDLE";
-      break;
-    case CURLM_BAD_EASY_HANDLE:
-      s = "CURLM_BAD_EASY_HANDLE";
-      break;
-    case CURLM_OUT_OF_MEMORY:
-      s = "CURLM_OUT_OF_MEMORY";
-      break;
-    case CURLM_INTERNAL_ERROR:
-      s = "CURLM_INTERNAL_ERROR";
-      break;
-    case CURLM_UNKNOWN_OPTION:
-      s = "CURLM_UNKNOWN_OPTION";
-      break;
-    case CURLM_LAST:
-      s = "CURLM_LAST";
-      break;
-    default:
-      s = "CURLM_unknown";
-      break;
-    case CURLM_BAD_SOCKET:
-      s = "CURLM_BAD_SOCKET";
-      fprintf(MSG_OUT, "\nERROR: %s returns %s", where, s);
-      /* ignore this error */
-      return;
-    }
-
-    fprintf(MSG_OUT, "\nERROR: %s returns %s", where, s);
-
-    exit(code);
-  }
-}
-
-/* Check for completed transfers, and remove their easy handles */
-static void check_multi_info(GlobalInfo *g)
-{
-  char *eff_url;
-  CURLMsg *msg;
-  int msgs_left;
-  ConnInfo *conn;
-  CURL *easy;
-  CURLcode res;
-
-  fprintf(MSG_OUT, "\nREMAINING: %d", g->still_running);
-
-  while((msg = curl_multi_info_read(g->multi, &msgs_left))) {
-    if(msg->msg == CURLMSG_DONE) {
-      easy = msg->easy_handle;
-      res = msg->data.result;
-      curl_easy_getinfo(easy, CURLINFO_PRIVATE, &conn);
-      curl_easy_getinfo(easy, CURLINFO_EFFECTIVE_URL, &eff_url);
-      fprintf(MSG_OUT, "\nDONE: %s => (%d) %s", eff_url, res, conn->error);
-      curl_multi_remove_handle(g->multi, easy);
-      free(conn->url);
-      curl_easy_cleanup(easy);
-      free(conn);
-    }
-  }
-}
-
-/* Called by asio when there is an action on a socket */
-static void event_cb(GlobalInfo *g, curl_socket_t s,
-                     int action, const boost::system::error_code & error,
-                     int *fdp)
-{
-  fprintf(MSG_OUT, "\nevent_cb: action=%d", action);
-
-  if(socket_map.find(s) == socket_map.end()) {
-    fprintf(MSG_OUT, "\nevent_cb: socket already closed");
-    return;
-  }
-
-  /* make sure the event matches what are wanted */
-  if(*fdp == action || *fdp == CURL_POLL_INOUT) {
-    CURLMcode rc;
-    if(error)
-      action = CURL_CSELECT_ERR;
-    rc = curl_multi_socket_action(g->multi, s, action, &g->still_running);
-
-    mcode_or_die("event_cb: curl_multi_socket_action", rc);
-    check_multi_info(g);
-
-    if(g->still_running <= 0) {
-      fprintf(MSG_OUT, "\nlast transfer done, kill timeout");
-      timer.cancel();
-    }
-
-    /* keep on watching.
-     * the socket may have been closed and/or fdp may have been changed
-     * in curl_multi_socket_action(), so check them both */
-    if(!error && socket_map.find(s) != socket_map.end() &&
-       (*fdp == action || *fdp == CURL_POLL_INOUT)) {
-      boost::asio::ip::tcp::socket *tcp_socket = socket_map.find(s)->second;
-
-      if(action == CURL_POLL_IN) {
-        tcp_socket->async_read_some(boost::asio::null_buffers(),
-                                    boost::bind(&event_cb, g, s,
-                                                action, _1, fdp));
-      }
-      if(action == CURL_POLL_OUT) {
-        tcp_socket->async_write_some(boost::asio::null_buffers(),
-                                     boost::bind(&event_cb, g, s,
-                                                 action, _1, fdp));
-      }
-    }
-  }
-}
-
-/* Called by asio when our timeout expires */
-static void timer_cb(const boost::system::error_code & error, GlobalInfo *g)
-{
-  if(!error) {
-    fprintf(MSG_OUT, "\ntimer_cb: ");
-
-    CURLMcode rc;
-    rc = curl_multi_socket_action(g->multi, CURL_SOCKET_TIMEOUT, 0,
-                                  &g->still_running);
-
-    mcode_or_die("timer_cb: curl_multi_socket_action", rc);
-    check_multi_info(g);
-  }
-}
-
-/* Clean up any data */
-static void remsock(int *f, GlobalInfo *g)
-{
-  fprintf(MSG_OUT, "\nremsock: ");
-
-  if(f) {
-    free(f);
-  }
-}
-
-static void setsock(int *fdp, curl_socket_t s, CURL *e, int act, int oldact,
-                    GlobalInfo *g)
-{
-  fprintf(MSG_OUT, "\nsetsock: socket=%d, act=%d, fdp=%p", s, act, fdp);
-
-  std::map<curl_socket_t, boost::asio::ip::tcp::socket *>::iterator it =
-    socket_map.find(s);
-
-  if(it == socket_map.end()) {
-    fprintf(MSG_OUT, "\nsocket %d is a c-ares socket, ignoring", s);
-    return;
-  }
-
-  boost::asio::ip::tcp::socket * tcp_socket = it->second;
-
-  *fdp = act;
-
-  if(act == CURL_POLL_IN) {
-    fprintf(MSG_OUT, "\nwatching for socket to become readable");
-    if(oldact != CURL_POLL_IN && oldact != CURL_POLL_INOUT) {
-      tcp_socket->async_read_some(boost::asio::null_buffers(),
-                                  boost::bind(&event_cb, g, s,
-                                              CURL_POLL_IN, _1, fdp));
-    }
-  }
-  else if(act == CURL_POLL_OUT) {
-    fprintf(MSG_OUT, "\nwatching for socket to become writable");
-    if(oldact != CURL_POLL_OUT && oldact != CURL_POLL_INOUT) {
-      tcp_socket->async_write_some(boost::asio::null_buffers(),
-                                   boost::bind(&event_cb, g, s,
-                                               CURL_POLL_OUT, _1, fdp));
-    }
-  }
-  else if(act == CURL_POLL_INOUT) {
-    fprintf(MSG_OUT, "\nwatching for socket to become readable & writable");
-    if(oldact != CURL_POLL_IN && oldact != CURL_POLL_INOUT) {
-      tcp_socket->async_read_some(boost::asio::null_buffers(),
-                                  boost::bind(&event_cb, g, s,
-                                              CURL_POLL_IN, _1, fdp));
-    }
-    if(oldact != CURL_POLL_OUT && oldact != CURL_POLL_INOUT) {
-      tcp_socket->async_write_some(boost::asio::null_buffers(),
-                                   boost::bind(&event_cb, g, s,
-                                               CURL_POLL_OUT, _1, fdp));
-    }
-  }
-}
-
-static void addsock(curl_socket_t s, CURL *easy, int action, GlobalInfo *g)
-{
-  /* fdp is used to store current action */
-  int *fdp = (int *) calloc(sizeof(int), 1);
-
-  setsock(fdp, s, easy, action, 0, g);
-  curl_multi_assign(g->multi, s, fdp);
-}
-
-/* CURLMOPT_SOCKETFUNCTION */
-static int sock_cb(CURL *e, curl_socket_t s, int what, void *cbp, void *sockp)
-{
-  fprintf(MSG_OUT, "\nsock_cb: socket=%d, what=%d, sockp=%p", s, what, sockp);
-
-  GlobalInfo *g = (GlobalInfo*) cbp;
-  int *actionp = (int *) sockp;
-  const char *whatstr[] = { "none", "IN", "OUT", "INOUT", "REMOVE"};
-
-  fprintf(MSG_OUT,
-          "\nsocket callback: s=%d e=%p what=%s ", s, e, whatstr[what]);
-
-  if(what == CURL_POLL_REMOVE) {
-    fprintf(MSG_OUT, "\n");
-    remsock(actionp, g);
-  }
-  else {
-    if(!actionp) {
-      fprintf(MSG_OUT, "\nAdding data: %s", whatstr[what]);
-      addsock(s, e, what, g);
-    }
-    else {
-      fprintf(MSG_OUT,
-              "\nChanging action from %s to %s",
-              whatstr[*actionp], whatstr[what]);
-      setsock(actionp, s, e, what, *actionp, g);
-    }
-  }
-
-  return 0;
-}
-
-/* CURLOPT_WRITEFUNCTION */
-static size_t write_cb(void *ptr, size_t size, size_t nmemb, void *data)
-{
-  size_t written = size * nmemb;
-  char *pBuffer = (char *)malloc(written + 1);
-
-  strncpy(pBuffer, (const char *)ptr, written);
-  pBuffer[written] = '\0';
-
-  fprintf(MSG_OUT, "%s", pBuffer);
-
-  free(pBuffer);
-
-  return written;
-}
-
-/* CURLOPT_PROGRESSFUNCTION */
-static int prog_cb(void *p, double dltotal, double dlnow, double ult,
-                   double uln)
-{
-  ConnInfo *conn = (ConnInfo *)p;
-
-  (void)ult;
-  (void)uln;
-
-  fprintf(MSG_OUT, "\nProgress: %s (%g/%g)", conn->url, dlnow, dltotal);
-  fprintf(MSG_OUT, "\nProgress: %s (%g)", conn->url, ult);
-
-  return 0;
-}
-
-/* CURLOPT_OPENSOCKETFUNCTION */
-static curl_socket_t opensocket(void *clientp, curlsocktype purpose,
-                                struct curl_sockaddr *address)
-{
-  fprintf(MSG_OUT, "\nopensocket :");
-
-  curl_socket_t sockfd = CURL_SOCKET_BAD;
-
-  /* restrict to IPv4 */
-  if(purpose == CURLSOCKTYPE_IPCXN && address->family == AF_INET) {
-    /* create a tcp socket object */
-    boost::asio::ip::tcp::socket *tcp_socket =
-      new boost::asio::ip::tcp::socket(io_service);
-
-    /* open it and get the native handle*/
-    boost::system::error_code ec;
-    tcp_socket->open(boost::asio::ip::tcp::v4(), ec);
-
-    if(ec) {
-      /* An error occurred */
-      std::cout << std::endl << "Couldn't open socket [" << ec << "][" <<
-        ec.message() << "]";
-      fprintf(MSG_OUT, "\nERROR: Returning CURL_SOCKET_BAD to signal error");
-    }
-    else {
-      sockfd = tcp_socket->native_handle();
-      fprintf(MSG_OUT, "\nOpened socket %d", sockfd);
-
-      /* save it for monitoring */
-      socket_map.insert(std::pair<curl_socket_t,
-                        boost::asio::ip::tcp::socket *>(sockfd, tcp_socket));
-    }
-  }
-
-  return sockfd;
-}
-
-/* CURLOPT_CLOSESOCKETFUNCTION */
-static int close_socket(void *clientp, curl_socket_t item)
-{
-  fprintf(MSG_OUT, "\nclose_socket : %d", item);
-
-  std::map<curl_socket_t, boost::asio::ip::tcp::socket *>::iterator it =
-    socket_map.find(item);
-
-  if(it != socket_map.end()) {
-    delete it->second;
-    socket_map.erase(it);
-  }
-
-  return 0;
-}
-
-/* Create a new easy handle, and add it to the global curl_multi */
-static void new_conn(char *url, GlobalInfo *g)
-{
-  ConnInfo *conn;
-  CURLMcode rc;
-
-  conn = (ConnInfo *) calloc(1, sizeof(ConnInfo));
-
-  conn->easy = curl_easy_init();
-  if(!conn->easy) {
-    fprintf(MSG_OUT, "\ncurl_easy_init() failed, exiting!");
-    exit(2);
-  }
-
-  conn->global = g;
-  conn->url = strdup(url);
-  curl_easy_setopt(conn->easy, CURLOPT_URL, conn->url);
-  curl_easy_setopt(conn->easy, CURLOPT_WRITEFUNCTION, write_cb);
-  curl_easy_setopt(conn->easy, CURLOPT_WRITEDATA, &conn);
-  curl_easy_setopt(conn->easy, CURLOPT_VERBOSE, 1L);
-  curl_easy_setopt(conn->easy, CURLOPT_ERRORBUFFER, conn->error);
-  curl_easy_setopt(conn->easy, CURLOPT_PRIVATE, conn);
-  curl_easy_setopt(conn->easy, CURLOPT_NOPROGRESS, 1L);
-  curl_easy_setopt(conn->easy, CURLOPT_PROGRESSFUNCTION, prog_cb);
-  curl_easy_setopt(conn->easy, CURLOPT_PROGRESSDATA, conn);
-  curl_easy_setopt(conn->easy, CURLOPT_LOW_SPEED_TIME, 3L);
-  curl_easy_setopt(conn->easy, CURLOPT_LOW_SPEED_LIMIT, 10L);
-
-  /* call this function to get a socket */
-  curl_easy_setopt(conn->easy, CURLOPT_OPENSOCKETFUNCTION, opensocket);
-
-  /* call this function to close a socket */
-  curl_easy_setopt(conn->easy, CURLOPT_CLOSESOCKETFUNCTION, close_socket);
-
-  fprintf(MSG_OUT,
-          "\nAdding easy %p to multi %p (%s)", conn->easy, g->multi, url);
-  rc = curl_multi_add_handle(g->multi, conn->easy);
-  mcode_or_die("new_conn: curl_multi_add_handle", rc);
-
-  /* note that the add_handle() will set a time-out to trigger very soon so
-     that the necessary socket_action() call will be called by this app */
-}
-
-int main(int argc, char **argv)
-{
-  GlobalInfo g;
-
-  (void)argc;
-  (void)argv;
-
-  memset(&g, 0, sizeof(GlobalInfo));
-  g.multi = curl_multi_init();
-
-  curl_multi_setopt(g.multi, CURLMOPT_SOCKETFUNCTION, sock_cb);
-  curl_multi_setopt(g.multi, CURLMOPT_SOCKETDATA, &g);
-  curl_multi_setopt(g.multi, CURLMOPT_TIMERFUNCTION, multi_timer_cb);
-  curl_multi_setopt(g.multi, CURLMOPT_TIMERDATA, &g);
-
-  new_conn((char *)"www.google.com", &g);  /* add a URL */
-
-  /* enter io_service run loop */
-  io_service.run();
-
-  curl_multi_cleanup(g.multi);
-
-  fprintf(MSG_OUT, "\ndone.\n");
-
-  return 0;
-}