examples: bring back curl_formadd-using examples

  imap-search imap-create imap-delete imap-copy imap-noop imap-ssl         \

  imap-tls imap-multi url2file sftpget ftpsget postinmemory http2-download \

  http2-upload http2-serverpush getredirect ftpuploadfrommem               \

  ftpuploadresume sslbackend

  ftpuploadresume sslbackend postit2-formadd multi-formadd

# These examples require external dependencies that may not be commonly

# available on POSIX systems, so don't bother attempting to compile them here.

/***************************************************************************

 *                                  _   _ ____  _

 *  Project                     ___| | | |  _ \| |

 *                             / __| | | | |_) | |

 *                            | (__| |_| |  _ <| |___

 *                             \___|\___/|_| \_\_____|

 *

 * Copyright (C) 1998 - 2017, 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>

 * using the multi interface to do a multipart formpost without blocking

 * </DESC>

 */

#include <stdio.h>

#include <string.h>

#include <sys/time.h>

#include <curl/curl.h>

int main(void)

{

  CURL *curl;

  CURLM *multi_handle;

  int still_running;

  struct curl_httppost *formpost = NULL;

  struct curl_httppost *lastptr = NULL;

  struct curl_slist *headerlist = NULL;

  static const char buf[] = "Expect:";

  /* Fill in the file upload field. This makes libcurl load data from

     the given file name when curl_easy_perform() is called. */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "sendfile",

               CURLFORM_FILE, "postit2.c",

               CURLFORM_END);

  /* Fill in the filename field */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "filename",

               CURLFORM_COPYCONTENTS, "postit2.c",

               CURLFORM_END);

  /* Fill in the submit field too, even if this is rarely needed */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "submit",

               CURLFORM_COPYCONTENTS, "send",

               CURLFORM_END);

  curl = curl_easy_init();

  multi_handle = curl_multi_init();

  /* initialize custom header list (stating that Expect: 100-continue is not

     wanted */

  headerlist = curl_slist_append(headerlist, buf);

  if(curl && multi_handle) {

    /* what URL that receives this POST */

    curl_easy_setopt(curl, CURLOPT_URL, "http://www.example.com/upload.cgi");

    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);

    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);

    curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);

    curl_multi_add_handle(multi_handle, curl);

    curl_multi_perform(multi_handle, &still_running);

    do {

      struct timeval timeout;

      int rc; /* select() return code */

      CURLMcode mc; /* curl_multi_fdset() return code */

      fd_set fdread;

      fd_set fdwrite;

      fd_set fdexcep;

      int maxfd = -1;

      long curl_timeo = -1;

      FD_ZERO(&fdread);

      FD_ZERO(&fdwrite);

      FD_ZERO(&fdexcep);

      /* set a suitable timeout to play around with */

      timeout.tv_sec = 1;

      timeout.tv_usec = 0;

      curl_multi_timeout(multi_handle, &curl_timeo);

      if(curl_timeo >= 0) {

        timeout.tv_sec = curl_timeo / 1000;

        if(timeout.tv_sec > 1)

          timeout.tv_sec = 1;

        else

          timeout.tv_usec = (curl_timeo % 1000) * 1000;

      }

      /* get file descriptors from the transfers */

      mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);

      if(mc != CURLM_OK) {

        fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);

        break;

      }

      /* On success the value of maxfd is guaranteed to be >= -1. We call

         select(maxfd + 1, ...); specially in case of (maxfd == -1) there are

         no fds ready yet so we call select(0, ...) --or Sleep() on Windows--

         to sleep 100ms, which is the minimum suggested value in the

         curl_multi_fdset() doc. */

      if(maxfd == -1) {

#ifdef _WIN32

        Sleep(100);

        rc = 0;

#else

        /* Portable sleep for platforms other than Windows. */

        struct timeval wait = { 0, 100 * 1000 }; /* 100ms */

        rc = select(0, NULL, NULL, NULL, &wait);

#endif

      }

      else {

        /* Note that on some platforms 'timeout' may be modified by select().

           If you need access to the original value save a copy beforehand. */

        rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout);

      }

      switch(rc) {

      case -1:

        /* select error */

        break;

      case 0:

      default:

        /* timeout or readable/writable sockets */

        printf("perform!\n");

        curl_multi_perform(multi_handle, &still_running);

        printf("running: %d!\n", still_running);

        break;

      }

    } while(still_running);

    curl_multi_cleanup(multi_handle);

    /* always cleanup */

    curl_easy_cleanup(curl);

    /* then cleanup the formpost chain */

    curl_formfree(formpost);

    /* free slist */

    curl_slist_free_all(headerlist);

  }

  return 0;

}

/***************************************************************************

 *                                  _   _ ____  _

 *  Project                     ___| | | |  _ \| |

 *                             / __| | | | |_) | |

 *                            | (__| |_| |  _ <| |___

 *                             \___|\___/|_| \_\_____|

 *

 * Copyright (C) 1998 - 2017, 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>

 * HTTP Multipart formpost with file upload and two additional parts.

 * </DESC>

 */

/* Example code that uploads a file name 'foo' to a remote script that accepts

 * "HTML form based" (as described in RFC1738) uploads using HTTP POST.

 *

 * The imaginary form we'll fill in looks like:

 *

 * <form method="post" enctype="multipart/form-data" action="examplepost.cgi">

 * Enter file: <input type="file" name="sendfile" size="40">

 * Enter file name: <input type="text" name="filename" size="30">

 * <input type="submit" value="send" name="submit">

 * </form>

 *

 * This exact source code has not been verified to work.

 */

#include <stdio.h>

#include <string.h>

#include <curl/curl.h>

int main(int argc, char *argv[])

{

  CURL *curl;

  CURLcode res;

  struct curl_httppost *formpost = NULL;

  struct curl_httppost *lastptr = NULL;

  struct curl_slist *headerlist = NULL;

  static const char buf[] = "Expect:";

  curl_global_init(CURL_GLOBAL_ALL);

  /* Fill in the file upload field */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "sendfile",

               CURLFORM_FILE, "postit2.c",

               CURLFORM_END);

  /* Fill in the filename field */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "filename",

               CURLFORM_COPYCONTENTS, "postit2.c",

               CURLFORM_END);

  /* Fill in the submit field too, even if this is rarely needed */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "submit",

               CURLFORM_COPYCONTENTS, "send",

               CURLFORM_END);

  curl = curl_easy_init();

  /* initialize custom header list (stating that Expect: 100-continue is not

     wanted */

  headerlist = curl_slist_append(headerlist, buf);

  if(curl) {

    /* what URL that receives this POST */

    curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/examplepost.cgi");

    if((argc == 2) && (!strcmp(argv[1], "noexpectheader")))

      /* only disable 100-continue header if explicitly requested */

      curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);

    curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);

    /* Perform the request, res will get the return code */

    res = curl_easy_perform(curl);

    /* Check for errors */

    if(res != CURLE_OK)

      fprintf(stderr, "curl_easy_perform() failed: %s\n",

              curl_easy_strerror(res));

    /* always cleanup */

    curl_easy_cleanup(curl);

    /* then cleanup the formpost chain */

    curl_formfree(formpost);

    /* free slist */

    curl_slist_free_all(headerlist);

  }

  return 0;

}