Implemented new function MHD_create_response_from_iovec()

Implemented the new function, related framework, and tests for iovec-based
responses.
The implementation is based on the patch provided by Lawrence Sebald and
Damon N. Earp from NASA.

doc/libmicrohttpd.texi

@@ -1270,6 +1270,11 @@ Handle for a response.
 @end deftp
 
 
+@deftp {C Struct} MHD_IoVec
+An element of an array of memory buffers.
+@end deftp
+
+
 @deftp {C Struct} MHD_PostProcessor
 @cindex POST method
 Handle for @code{POST} processing.
@@ -2170,6 +2175,28 @@ MHD_destroy_response(response);
 @end example
 
 
+@deftypefun {struct MHD_Response *} MHD_create_response_from_iovec (const struct MHD_IoVec *iov, int iovcnt, MHD_ContentReaderFreeCallback crfc, void *cls)
+Create a response object from an array of memory buffers.
+The response object can be extended with header information and then be used
+any number of times.
+@table @var
+@item iov
+the array for response data buffers, an internal copy of this will be made;
+
+@item iovcnt
+the number of elements in @var{iov};
+
+@item crfc
+the callback to call to free resources associated with @var{iov};
+
+@item cls
+the argument to @var{crfc};
+@end table
+
+Return @code{NULL} on error (i.e. invalid arguments, out of memory).
+@end deftypefun
+
+
 
 @c ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 

src/include/microhttpd.h

@@ -1973,6 +1973,23 @@ union MHD_ConnectionInfo
 };
 
 
+/**
+ * I/O vector type. Provided for use with MHD_create_response_from_iovec.
+ */
+struct MHD_IoVec
+{
+  /**
+   * The pointer to the memory region for I/O.
+   */
+  void *iov_base;
+
+  /**
+   * The size in bytes of the memory region for I/O.
+   */
+  size_t iov_len;
+};
+
+
 /**
  * Values of this enum are used to specify what
  * information about a connection is desired.
@@ -3229,6 +3246,27 @@ MHD_create_response_from_fd_at_offset64 (uint64_t size,
                                          uint64_t offset);
 
 
+/**
+ * Create a response object from an array of memory buffers.
+ * The response object can be extended with header information and then be used
+ * any number of times.
+ *
+ * @param iov the array for response data buffers, an internal copy of this
+ *        will be made
+ * @param iovcnt the number of elements in @a iov
+ * @param free_cb the callback to clean up any data associated with @a iov when
+ *        the response is destroyed.
+ * @param cls the argument passed to @a free_cb
+ * @return NULL on error (i.e. invalid arguments, out of memory)
+ * @ingroup response
+ */
+_MHD_EXTERN struct MHD_Response *
+MHD_create_response_from_iovec (const struct MHD_IoVec *iov,
+                                int iovcnt,
+                                MHD_ContentReaderFreeCallback free_cb,
+                                void *cls);
+
+
 /**
  * Enumeration for actions MHD should perform on the underlying socket
  * of the upgrade.  This API is not finalized, and in particular

src/microhttpd/connection.c

@@ -794,11 +794,33 @@ try_ready_normal_body (struct MHD_Connection *connection)
   struct MHD_Response *response;
 
   response = connection->response;
-  if (NULL == response->crc)
-    return MHD_YES;
   if ( (0 == response->total_size) ||
        (connection->response_write_position == response->total_size) )
     return MHD_YES; /* 0-byte response is always ready */
+  if (NULL != response->data_iov)
+  {
+    size_t copy_size;
+    if (NULL != connection->resp_iov.iov)
+      return MHD_YES;
+
+    copy_size = response->data_iovcnt * sizeof(MHD_iovec_);
+    connection->resp_iov.iov = MHD_pool_allocate (connection->pool, copy_size,
+                                                  true);
+    if (NULL == connection->resp_iov.iov)
+    {
+      MHD_mutex_unlock_chk_ (&response->mutex);
+      /* not enough memory */
+      CONNECTION_CLOSE_ERROR (connection,
+                              _ ("Closing connection (out of memory).\n"));
+      return MHD_NO;
+    }
+    memcpy (connection->resp_iov.iov, response->data_iov, copy_size);
+    connection->resp_iov.cnt = response->data_iovcnt;
+    connection->resp_iov.sent = 0;
+    return MHD_YES;
+  }
+  if (NULL == response->crc)
+    return MHD_YES;
   if ( (response->data_start <=
         connection->response_write_position) &&
        (response->data_size + response->data_start >
@@ -2935,6 +2957,7 @@ MHD_connection_handle_write (struct MHD_Connection *connection)
                     connection->response_write_position) );
 
       if ( (NULL == resp->crc) &&
+           (NULL == resp->data_iov) &&
            (0 == connection->response_write_position) )
       {
         mhd_assert (resp->total_size >= resp->data_size);
@@ -3017,12 +3040,16 @@ MHD_connection_handle_write (struct MHD_Connection *connection)
 #if defined(_MHD_HAVE_SENDFILE)
       if (MHD_resp_sender_sendfile == connection->resp_sender)
       {
+        mhd_assert (NULL == response->data_iov);
         ret = MHD_send_sendfile_ (connection);
       }
+      else /* combined with the next 'if' */
+#endif /* _MHD_HAVE_SENDFILE */
+      if (NULL != response->data_iov)
+      {
+        ret = MHD_send_iovec_ (connection, &connection->resp_iov, true);
+      }
       else
-#else  /* ! _MHD_HAVE_SENDFILE */
-      if (1)
-#endif /* ! _MHD_HAVE_SENDFILE */
       {
         data_write_offset = connection->response_write_position
                             - response->data_start;
@@ -3674,6 +3701,8 @@ MHD_connection_handle_idle (struct MHD_Connection *connection)
       connection->write_buffer_size = 0;
       connection->write_buffer_send_offset = 0;
       connection->write_buffer_append_offset = 0;
+      /* iov (if any) was deallocated by MHD_pool_reset */
+      memset (&connection->resp_iov, 0, sizeof(connection->resp_iov));
       continue;
     case MHD_CONNECTION_CLOSED:
       cleanup_connection (connection);

src/microhttpd/internal.h

@@ -343,6 +343,57 @@ struct MHD_HTTP_Header
 };
 
 
+#if defined(MHD_WINSOCK_SOCKETS)
+/**
+ * Internally used I/O vector type for use with winsock.
+ * Binary matches system "WSABUF".
+ */
+typedef struct _MHD_W32_iovec
+{
+  unsigned long iov_len;
+  char *iov_base;
+} MHD_iovec_;
+#define MHD_IOV_ELMN_MAX_SIZE    ULONG_MAX
+#elif defined(HAVE_SENDMSG) || defined(HAVE_WRITEV)
+/**
+ * Internally used I/O vector type for use when writev or sendmsg
+ * is available. Matches system "struct iovec".
+ */
+typedef struct iovec MHD_iovec_;
+#define MHD_IOV_ELMN_MAX_SIZE    SIZE_MAX
+#else
+/**
+ * Internally used I/O vector type for use when writev or sendmsg
+ * is not available.
+ */
+typedef struct MHD_IoVec MHD_iovec_;
+#define MHD_IOV_ELMN_MAX_SIZE    SIZE_MAX
+#endif
+
+
+struct MHD_iovec_track_
+{
+  /**
+   * The copy of array of iovec elements.
+   * The copy of elements are updated during sending.
+   * The number of elements is not changed during lifetime.
+   */
+  MHD_iovec_ *iov;
+
+  /**
+   * The number of elements in @iov.
+   * This value is not changed during lifetime.
+   */
+  size_t cnt;
+
+  /**
+   * The number of sent elements.
+   * At the same time, it is the index of the next (or current) element
+   * to send.
+   */
+  size_t sent;
+};
+
 /**
  * Representation of a response.
  */
@@ -450,6 +501,15 @@ struct MHD_Response
    */
   bool is_pipe;
 
+  /**
+   * I/O vector used with MHD_create_response_from_iovec.
+   */
+  MHD_iovec_ *data_iov;
+
+  /**
+   * Number of elements in data_iov.
+   */
+  size_t data_iovcnt;
 };
 
 
@@ -873,6 +933,15 @@ struct MHD_Connection
    */
   uint64_t response_write_position;
 
+  /**
+   * The copy of iov response.
+   * Valid if iovec response is used.
+   * Updated during send.
+   * Members are allocated in the pool.
+   */
+  struct MHD_iovec_track_ resp_iov;
+
+
 #if defined(_MHD_HAVE_SENDFILE)
   enum MHD_resp_sender_
   {

src/microhttpd/mhd_send.c

@@ -51,6 +51,15 @@
 
 #include "mhd_limits.h"
 
+#ifdef MHD_VECT_SEND
+#if (! defined (HAVE_SENDMSG) || ! defined(MSG_NOSIGNAL)) && \
+  defined (MHD_SEND_SPIPE_SUPPRESS_POSSIBLE) && \
+  defined (MHD_SEND_SPIPE_SUPPRESS_NEEDED)
+#define _MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED 1
+#endif /* (!HAVE_SENDMSG || !MSG_NOSIGNAL) &&
+          MHD_SEND_SPIPE_SUPPRESS_POSSIBLE && MHD_SEND_SPIPE_SUPPRESS_NEEDED */
+#endif /* MHD_VECT_SEND */
+
 /**
  * sendfile() chuck size
  */
@@ -1243,3 +1252,237 @@ MHD_send_sendfile_ (struct MHD_Connection *connection)
 
 
 #endif /* _MHD_HAVE_SENDFILE */
+
+#if defined(MHD_VECT_SEND)
+
+
+/**
+ * Function sends iov data by system sendmsg or writev function.
+ *
+ * Connection must be in non-TLS (non-HTTPS) mode.
+ *
+ * @param connection the MHD connection structure
+ * @param r_iov the pointer to iov data structure with tracking
+ * @param push_data set to true to force push the data to the network from
+ *                  system buffers (usually set for the last piece of data),
+ *                  set to false to prefer holding incomplete network packets
+ *                  (more data will be send for the same reply).
+ * @return actual number of bytes sent
+ */
+static ssize_t
+send_iov_nontls (struct MHD_Connection *connection,
+                 struct MHD_iovec_track_ *const r_iov,
+                 bool push_data)
+{
+  ssize_t res;
+  ssize_t total_sent;
+  size_t items_to_send;
+#ifdef HAVE_SENDMSG
+  struct msghdr msg;
+#elif defined(MHD_WINSOCK_SOCKETS)
+  DWORD bytes_sent;
+  DWORD cnt_w;
+#endif /* MHD_WINSOCK_SOCKETS */
+
+  mhd_assert (0 == (connection->daemon->options & MHD_USE_TLS));
+
+  if ( (MHD_INVALID_SOCKET == connection->socket_fd) ||
+       (MHD_CONNECTION_CLOSED == connection->state) )
+  {
+    return MHD_ERR_NOTCONN_;
+  }
+
+  pre_send_setopt (connection, false, push_data);
+
+  items_to_send = r_iov->cnt - r_iov->sent;
+#ifdef HAVE_SENDMSG
+  memset (&msg, 0, sizeof(struct msghdr));
+  msg.msg_iov = r_iov->iov + r_iov->sent;
+  msg.msg_iovlen = items_to_send;
+
+  res = sendmsg (connection->socket_fd, &msg, MSG_NOSIGNAL_OR_ZERO);
+#elif defined(HAVE_WRITEV)
+  res = writev (connection->socket_fd, r_iov->iov + r_iov->sent,
+                items_to_send);
+#elif defined(MHD_WINSOCK_SOCKETS)
+#ifdef _WIN64
+  cnt_w = (items_to_send > UINT32_MAX) ? UINT32_MAX : (DWORD) items_to_send;
+#else  /* ! _WIN64 */
+  cnt_w = (DWORD) items_to_send;
+#endif /* ! _WIN64 */
+  if (0 == WSASend (connection->socket_fd,
+                    (LPWSABUF) (r_iov->iov + r_iov->sent),
+                    cnt_w,
+                    &bytes_sent, 0, NULL, NULL))
+    res = (ssize_t) bytes_sent;
+  else
+    res = -1;
+#else /* !HAVE_SENDMSG && !HAVE_WRITEV && !MHD_WINSOCK_SOCKETS */
+#error No vector-send function available
+#endif
+
+  if (0 > res)
+  {
+    const int err = MHD_socket_get_error_ ();
+
+    if (MHD_SCKT_ERR_IS_EAGAIN_ (err))
+    {
+#ifdef EPOLL_SUPPORT
+      /* EAGAIN --- no longer write-ready */
+      connection->epoll_state &= ~MHD_EPOLL_STATE_WRITE_READY;
+#endif /* EPOLL_SUPPORT */
+      return MHD_ERR_AGAIN_;
+    }
+    if (MHD_SCKT_ERR_IS_EINTR_ (err))
+      return MHD_ERR_AGAIN_;
+    if (MHD_SCKT_ERR_IS_ (err, MHD_SCKT_ECONNRESET_))
+      return MHD_ERR_CONNRESET_;
+    /* Treat any other error as hard error. */
+    return MHD_ERR_NOTCONN_;
+  }
+
+  /* Some data has been sent */
+  total_sent = res;
+  /* Adjust the internal tracking information for the iovec to
+   * take this last send into account. */
+  while ((0 != res) && (r_iov->iov[r_iov->sent].iov_len <= (size_t) res))
+  {
+    res -= r_iov->iov[r_iov->sent].iov_len;
+    r_iov->sent++; /* The iov element has been completely sent */
+    mhd_assert ((r_iov->cnt > r_iov->sent) || (0 == res));
+  }
+
+  if (r_iov->cnt == r_iov->sent)
+    post_send_setopt (connection, false, push_data);
+  else
+  {
+#ifdef EPOLL_SUPPORT
+    connection->epoll_state &= ~MHD_EPOLL_STATE_WRITE_READY;
+#endif /* EPOLL_SUPPORT */
+    if (0 != res)
+    {
+      mhd_assert (r_iov->cnt > r_iov->sent);
+      /* The last iov element has been partially sent */
+      r_iov->iov[r_iov->sent].iov_base =
+        (void*) ((uint8_t*) r_iov->iov[r_iov->sent].iov_base + (size_t) res);
+      r_iov->iov[r_iov->sent].iov_len -= res;
+    }
+  }
+
+  return total_sent;
+}
+
+
+#endif /* MHD_VECT_SEND */
+
+#if ! defined(MHD_VECT_SEND) || defined(HTTPS_SUPPORT) || \
+  defined(_MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED)
+
+
+/**
+ * Function sends iov data by sending buffers one-by-one by standard
+ * data send function.
+ *
+ * Connection could be in HTTPS or non-HTTPS mode.
+ *
+ * @param connection the MHD connection structure
+ * @param r_iov the pointer to iov data structure with tracking
+ * @param push_data set to true to force push the data to the network from
+ *                  system buffers (usually set for the last piece of data),
+ *                  set to false to prefer holding incomplete network packets
+ *                  (more data will be send for the same reply).
+ * @return actual number of bytes sent
+ */
+static ssize_t
+send_iov_emu (struct MHD_Connection *connection,
+              struct MHD_iovec_track_ *const r_iov,
+              bool push_data)
+{
+  const bool non_blk = connection->sk_nonblck;
+  size_t total_sent;
+  ssize_t res;
+
+  mhd_assert (NULL != r_iov->iov);
+  total_sent = 0;
+  do
+  {
+    if ((size_t) SSIZE_MAX - total_sent < r_iov->iov[r_iov->sent].iov_len)
+      return total_sent; /* return value would overflow */
+
+    res = MHD_send_data_ (connection,
+                          r_iov->iov[r_iov->sent].iov_base,
+                          r_iov->iov[r_iov->sent].iov_len,
+                          push_data && (r_iov->cnt == r_iov->sent + 1));
+    if (0 > res)
+    {
+      /* Result is an error */
+      if (0 == total_sent)
+        return res; /* Nothing was sent, return result as is */
+
+      if (MHD_ERR_AGAIN_ == res)
+        return total_sent; /* Some data has been sent, return the amount */
+
+      return res; /* Any kind of a hard error */
+    }
+
+    total_sent += (size_t) res;
+
+    if (r_iov->iov[r_iov->sent].iov_len != (size_t) res)
+    {
+      /* Incomplete buffer has been sent.
+       * Adjust buffer of the last element. */
+      r_iov->iov[r_iov->sent].iov_base =
+        (void*) ((uint8_t*) r_iov->iov[r_iov->sent].iov_base + (size_t) res);
+      r_iov->iov[r_iov->sent].iov_len -= res;
+
+      return total_sent;
+    }
+    /* The iov element has been completely sent */
+    r_iov->sent++;
+  } while ((r_iov->cnt > r_iov->sent) && (non_blk));
+
+  return (ssize_t) total_sent;
+}
+
+
+#endif /* !MHD_VECT_SEND || HTTPS_SUPPORT
+          || _MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED */
+
+
+ssize_t
+MHD_send_iovec_ (struct MHD_Connection *connection,
+                 struct MHD_iovec_track_ *const r_iov,
+                 bool push_data)
+{
+#ifdef MHD_VECT_SEND
+#if defined(HTTPS_SUPPORT) || \
+  defined(_MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED)
+  bool use_iov_send = true;
+#endif /* HTTPS_SUPPORT || _MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED */
+#endif /* MHD_VECT_SEND */
+
+  mhd_assert (NULL != connection->resp_iov.iov);
+  mhd_assert (NULL != connection->response->data_iov);
+  mhd_assert (connection->resp_iov.cnt > connection->resp_iov.sent);
+#ifdef MHD_VECT_SEND
+#if defined(HTTPS_SUPPORT) || \
+  defined(_MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED)
+#ifdef HTTPS_SUPPORT
+  use_iov_send = use_iov_send &&
+                 (0 == (connection->daemon->options & MHD_USE_TLS));
+#endif /* HTTPS_SUPPORT */
+#ifdef _MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED
+  use_iov_send = use_iov_send && (connection->daemon->sigpipe_blocked ||
+                                  connection->sk_spipe_suppress);
+#endif /* _MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED */
+  if (use_iov_send)
+#endif /* HTTPS_SUPPORT || _MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED */
+  return send_iov_nontls (connection, r_iov, push_data);
+#endif /* MHD_VECT_SEND */
+
+#if ! defined(MHD_VECT_SEND) || defined(HTTPS_SUPPORT) || \
+  defined(_MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED)
+  return send_iov_emu (connection, r_iov, push_data);
+#endif /* !MHD_VECT_SEND || HTTPS_SUPPORT
+          || _MHD_VECT_SEND_NEEDS_SPIPE_SUPPRESSED */
+}

src/microhttpd/mhd_send.h

@@ -41,6 +41,11 @@
 #include "connection_https.h"
 #endif
 
+#if defined(HAVE_SENDMSG) || defined(HAVE_WRITEV) || \
+  defined(MHD_WINSOCK_SOCKETS)
+#define MHD_VECT_SEND 1
+#endif /* HAVE_SENDMSG || HAVE_WRITEV || MHD_WINSOCK_SOCKETS */
+
 #ifdef HAVE_FREEBSD_SENDFILE
 /**
  * Initialises static variables
@@ -125,4 +130,21 @@ MHD_connection_set_nodelay_state_ (struct MHD_Connection *connection,
                                    bool nodelay_state);
 
 
+/**
+ * Function for sending responses backed by a an array of memory buffers.
+ *
+ * @param connection the MHD connection structure
+ * @param r_iov the pointer to iov response structure with tracking
+ * @param push_data set to true to force push the data to the network from
+ *                  system buffers (usually set for the last piece of data),
+ *                  set to false to prefer holding incomplete network packets
+ *                  (more data will be send for the same reply).
+ * @return actual number of bytes sent
+ */
+ssize_t
+MHD_send_iovec_ (struct MHD_Connection *connection,
+                 struct MHD_iovec_track_ *r_iov,
+                 bool push_data);
+
+
 #endif /* MHD_SEND_H */

src/microhttpd/response.c

@@ -846,6 +846,153 @@ MHD_create_response_from_buffer_with_free_callback (size_t size,
 }
 
 
+/**
+ * Create a response object from an array of memory buffers.
+ * The response object can be extended with header information and then be used
+ * any number of times.
+ *
+ * @param iov the array for response data buffers, an internal copy of this
+ *        will be made
+ * @param iovcnt the number of elements in @a iov
+ * @param free_cb the callback to clean up any data associated with @a iov when
+ *        the response is destroyed.
+ * @param cls the argument passed to @a free_cb
+ * @return NULL on error (i.e. invalid arguments, out of memory)
+ */
+_MHD_EXTERN struct MHD_Response *
+MHD_create_response_from_iovec (const struct MHD_IoVec *iov,
+                                int iovcnt,
+                                MHD_ContentReaderFreeCallback free_cb,
+                                void *cls)
+{
+  struct MHD_Response *response;
+
+  if ((NULL == iov) && (0 < iovcnt))
+    return NULL;
+
+  response = MHD_calloc_ (1, sizeof (struct MHD_Response));
+  if (NULL != response)
+  {
+    if (MHD_mutex_init_ (&response->mutex))
+    {
+      int i;
+      int i_cp; /**< Index in the copy of iov */
+      uint64_t total_size;
+      void *last_valid_buffer;
+
+      i_cp = 0;
+      total_size = 0;
+      last_valid_buffer = NULL;
+      /* Calculate final size, number of valid elements, and check 'iov' */
+      for (i = 0; iovcnt > i; ++i)
+      {
+#if defined(MHD_WINSOCK_SOCKETS) && defined(_WIN64)
+        int64_t i_add;
+#endif /* ! MHD_WINSOCK_SOCKETS && _WIN64 */
+        if (0 == iov[i].iov_len)
+          continue; /* skip zero-sized elements */
+
+        if (NULL == iov[i].iov_base)
+        {
+          i_cp = -1; /* error */
+          break;
+        }
+        if ( (total_size > (total_size + iov[i].iov_len)) ||
+             (INT_MAX == i_cp) ||
+             (SSIZE_MAX < iov[i].iov_len) )
+        {
+          i_cp = -1; /* overflow */
+          break;
+        }
+        last_valid_buffer = iov[i].iov_base;
+        total_size += iov[i].iov_len;
+#if defined(MHD_POSIX_SOCKETS) || ! defined(_WIN64)
+        i_cp++;
+#else  /* ! MHD_POSIX_SOCKETS && _WIN64 */
+        i_add = iov[i].iov_len / ULONG_MAX;
+        if (0 != iov[i].iov_len % ULONG_MAX)
+          i_add++;
+        if (INT_MAX < (i_add + i_cp))
+        {
+          i_cp = -1; /* overflow */
+          break;
+        }
+        i_cp += (int) i_add;
+#endif /* ! MHD_POSIX_SOCKETS && _WIN64 */
+      }
+      if (0 <= i_cp)
+      {
+        response->fd = -1;
+        response->reference_count = 1;
+        response->total_size = total_size;
+        response->crc_cls = cls;
+        response->crfc = free_cb;
+        if (1 < i_cp)
+        {
+          MHD_iovec_ *iov_copy;
+          int num_copy_elements = i_cp;
+
+          iov_copy = MHD_calloc_ (num_copy_elements, sizeof(MHD_iovec_));
+          if (NULL != iov_copy)
+          {
+            i_cp = 0;
+            for (i = 0; iovcnt > i; ++i)
+            {
+              size_t element_size;
+              uint8_t *buf;
+
+              if (0 == iov[i].iov_len)
+                continue; /* skip zero-sized elements */
+
+              buf = (uint8_t*) iov[i].iov_base;
+              element_size = iov[i].iov_len;
+#if defined(MHD_WINSOCK_SOCKETS) && defined(_WIN64)
+              while (ULONG_MAX < element_size)
+              {
+                iov_copy[i_cp].iov_base = (void*) buf;
+                iov_copy[i_cp].iov_len = ULONG_MAX;
+                buf += ULONG_MAX;
+                element_size -= ULONG_MAX;
+                i_cp++;
+              }
+#endif /* MHD_WINSOCK_SOCKETS && _WIN64 */
+              iov_copy[i_cp].iov_base = (void*) buf;
+              iov_copy[i_cp].iov_len = element_size;
+              i_cp++;
+            }
+
+            mhd_assert (num_copy_elements == i_cp);
+            response->data_iov = iov_copy;
+            response->data_iovcnt = i_cp;
+
+            return response;
+          }
+
+        }
+        else if (1 == i_cp)
+        {
+          mhd_assert (NULL != last_valid_buffer);
+          response->data = last_valid_buffer;
+          response->data_size = total_size;
+
+          return response;
+        }
+        else /* if (0 == i_nz) */
+        {
+          mhd_assert (0 == total_size);
+
+          return response;
+        }
+      }
+      /* Some error condition */
+      MHD_mutex_destroy_chk_ (&response->mutex);
+    }
+    free (response);
+  }
+  return NULL;
+}
+
+
 #ifdef UPGRADE_SUPPORT
 /**
  * This connection-specific callback is provided by MHD to
@@ -1287,6 +1434,12 @@ MHD_destroy_response (struct MHD_Response *response)
 #endif
   if (NULL != response->crfc)
     response->crfc (response->crc_cls);
+
+  if (NULL != response->data_iov)
+  {
+    free (response->data_iov);
+  }
+
   while (NULL != response->first_header)
   {
     pos = response->first_header;

src/testcurl/.gitignore

@@ -116,3 +116,5 @@ test_patch11
 /test_add_conn_cleanup
 /test_add_conn_cleanup_nolisten
 core
+/test_get_iovec
+/test_get_iovec11

src/testcurl/Makefile.am

@@ -78,6 +78,7 @@ endif
 if HAVE_CURL
 check_PROGRAMS = \
   test_get \
+  test_get_iovec \
   test_get_sendfile \
   test_delete \
   test_patch \
@@ -89,6 +90,7 @@ check_PROGRAMS = \
   test_parse_cookies \
   test_large_put \
   test_get11 \
+  test_get_iovec11 \
   test_get_sendfile11 \
   test_patch11 \
   test_put11 \
@@ -218,6 +220,12 @@ test_digestauth_with_arguments_LDADD = \
   $(top_builddir)/src/microhttpd/libmicrohttpd.la \
   @LIBGCRYPT_LIBS@ @LIBCURL@
 
+test_get_iovec_SOURCES = \
+  test_get_iovec.c mhd_has_in_name.h
+test_get_iovec_LDADD = \
+  $(top_builddir)/src/microhttpd/libmicrohttpd.la \
+  @LIBCURL@
+
 test_get_sendfile_SOURCES = \
   test_get_sendfile.c mhd_has_in_name.h
 test_get_sendfile_LDADD = \
@@ -306,7 +314,7 @@ test_put_chunked_SOURCES = \
 test_put_chunked_LDADD = \
   $(top_builddir)/src/microhttpd/libmicrohttpd.la \
   @LIBCURL@
-  
+
 test_add_conn_SOURCES = \
   test_add_conn.c $(top_srcdir)/src/microhttpd/test_helpers.h
 test_add_conn_CFLAGS = \
@@ -345,6 +353,12 @@ test_get11_LDADD = \
   $(top_builddir)/src/microhttpd/libmicrohttpd.la \
   @LIBCURL@
 
+test_get_iovec11_SOURCES = \
+  test_get_iovec.c mhd_has_in_name.h
+test_get_iovec11_LDADD = \
+  $(top_builddir)/src/microhttpd/libmicrohttpd.la \
+  @LIBCURL@
+
 test_get_sendfile11_SOURCES = \
   test_get_sendfile.c mhd_has_in_name.h
 test_get_sendfile11_LDADD = \

src/testcurl/https/.gitignore

@@ -53,4 +53,5 @@
 /mhds_multi_daemon_test
 /tls_authentication_test
 /tmp_ca_cert.pem
+/test_https_get_iovec
 *.exe

src/testcurl/https/Makefile.am

@@ -1,4 +1,6 @@
 # This Makefile.am is in the public domain
+EMPTY_ITEM =
+
 SUBDIRS = .
 
 if USE_COVERAGE
@@ -34,7 +36,9 @@ THREAD_ONLY_TESTS = \
   test_https_time_out \
   test_https_multi_daemon \
   test_https_get \
-  test_empty_response
+  test_empty_response \
+  test_https_get_iovec \
+  $(EMPTY_ITEM)
 
 check_PROGRAMS = \
   test_https_get_select
@@ -155,6 +159,16 @@ test_https_get_LDADD  = \
   $(top_builddir)/src/microhttpd/libmicrohttpd.la \
   $(MHD_TLS_LIB_LDFLAGS) $(MHD_TLS_LIBDEPS) @LIBGCRYPT_LIBS@ @LIBCURL@
 
+test_https_get_iovec_SOURCES = \
+  test_https_get_iovec.c \
+  tls_test_keys.h \
+  tls_test_common.h \
+  tls_test_common.c
+test_https_get_iovec_LDADD  = \
+  $(top_builddir)/src/testcurl/libcurl_version_check.a \
+  $(top_builddir)/src/microhttpd/libmicrohttpd.la \
+  $(MHD_TLS_LIB_LDFLAGS) $(MHD_TLS_LIBDEPS) @LIBGCRYPT_LIBS@ @LIBCURL@
+
 if HAVE_GNUTLS_SNI
 test_https_sni_SOURCES = \
   test_https_sni.c \

src/testcurl/https/test_https_get_iovec.c

@@ -0,0 +1,421 @@
+/*
+  This file is part of libmicrohttpd
+  Copyright (C) 2007-2021 Christian Grothoff
+  Copyright (C) 2016-2021 Evgeny Grin
+
+  libmicrohttpd is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published
+  by the Free Software Foundation; either version 3, or (at your
+  option) any later version.
+
+  libmicrohttpd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with libmicrohttpd; see the file COPYING.  If not, write to the
+  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+  Boston, MA 02110-1301, USA.
+*/
+
+/**
+ * @file test_https_get_iovec.c
+ * @brief  Testcase for libmicrohttpd HTTPS GET operations using an iovec
+ * @author Sagie Amir
+ * @author Karlson2k (Evgeny Grin)
+ * @author Lawrence Sebald
+ */
+
+/*
+ * This testcase is derived from the test_https_get.c testcase. This version
+ * adds the usage of a scatter/gather array for storing the response data.
+ */
+
+#include "platform.h"
+#include "microhttpd.h"
+#include <limits.h>
+#include <sys/stat.h>
+#include <curl/curl.h>
+#ifdef MHD_HTTPS_REQUIRE_GRYPT
+#include <gcrypt.h>
+#endif /* MHD_HTTPS_REQUIRE_GRYPT */
+#include "tls_test_common.h"
+
+extern const char srv_signed_cert_pem[];
+extern const char srv_signed_key_pem[];
+
+
+static int global_port;
+
+/* Use large enough pieces (>16KB) to test partially consumed
+ * data as TLS doesn't take more than 16KB by a single call. */
+#define TESTSTR_IOVLEN 20480
+#define TESTSTR_IOVCNT 30
+#define TESTSTR_SIZE   (TESTSTR_IOVCNT * TESTSTR_IOVLEN)
+
+
+static void
+iov_free_callback (void *cls)
+{
+  free (cls);
+}
+
+
+static int
+check_read_data (const void *ptr, size_t len)
+{
+  const int *buf;
+  size_t i;
+
+  if (len % sizeof(int))
+    return -1;
+
+  buf = (const int *) ptr;
+
+  for (i = 0; i < len / sizeof(int); ++i)
+  {
+    if (buf[i] != (int) i)
+      return -1;
+  }
+
+  return 0;
+}
+
+
+static enum MHD_Result
+iovec_ahc (void *cls,
+           struct MHD_Connection *connection,
+           const char *url,
+           const char *method,
+           const char *version,
+           const char *upload_data,
+           size_t *upload_data_size,
+           void **ptr)
+{
+  static int aptr;
+  struct MHD_Response *response;
+  enum MHD_Result ret;
+  int *data;
+  struct MHD_IoVec iov[TESTSTR_IOVCNT];
+  int i;
+  int j;
+  (void) cls; (void) url; (void) version;          /* Unused. Silent compiler warning. */
+  (void) upload_data; (void) upload_data_size;     /* Unused. Silent compiler warning. */
+
+  if (0 != strcmp (method, MHD_HTTP_METHOD_GET))
+    return MHD_NO;              /* unexpected method */
+  if (&aptr != *ptr)
+  {
+    /* do never respond on first call */
+    *ptr = &aptr;
+    return MHD_YES;
+  }
+  *ptr = NULL;                  /* reset when done */
+
+  /* Create some test data. */
+  if (NULL == (data = malloc (TESTSTR_SIZE)))
+    return MHD_NO;
+
+  for (j = 0; j < TESTSTR_IOVCNT; ++j)
+  {
+    /* Assign chunks of memory area in the reverse order
+     * to make non-continous set of data therefore
+     * possible buffer overruns could be detected */
+    iov[j].iov_base = data + (((TESTSTR_IOVCNT - 1) - j)
+                              * (TESTSTR_SIZE / TESTSTR_IOVCNT
+                                 / sizeof(int)));
+    iov[j].iov_len = TESTSTR_SIZE / TESTSTR_IOVCNT;
+
+    for (i = 0; i < (int) (TESTSTR_IOVLEN / sizeof(int)); ++i)
+      ((int*) iov[j].iov_base)[i] = i + (j * TESTSTR_IOVLEN / sizeof(int));
+  }
+
+  response = MHD_create_response_from_iovec (iov,
+                                             TESTSTR_IOVCNT,
+                                             &iov_free_callback,
+                                             data);
+  ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
+  MHD_destroy_response (response);
+  return ret;
+}
+
+
+static int
+test_iovec_transfer (void *cls,
+                     int port,
+                     const char *cipher_suite,
+                     int proto_version)
+{
+  int len;
+  int ret = 0;
+  struct CBC cbc;
+  char url[255];
+  (void) cls;    /* Unused. Silent compiler warning. */
+
+  len = TESTSTR_SIZE;
+  if (NULL == (cbc.buf = malloc (sizeof (char) * len)))
+  {
+    fprintf (stderr, MHD_E_MEM);
+    return -1;
+  }
+  cbc.size = len;
+  cbc.pos = 0;
+
+  if (gen_test_file_url (url,
+                         sizeof (url),
+                         port))
+  {
+    ret = -1;
+    goto cleanup;
+  }
+
+  if (CURLE_OK !=
+      send_curl_req (url, &cbc, cipher_suite, proto_version))
+  {
+    ret = -1;
+    goto cleanup;
+  }
+
+  /* compare test file & daemon response */
+  if ((cbc.pos != TESTSTR_SIZE) ||
+      (0 != check_read_data (cbc.buf, cbc.pos)))
+  {
+    fprintf (stderr, "Error: local file & received file differ.\n");
+    ret = -1;
+  }
+cleanup:
+  free (cbc.buf);
+  return ret;
+}
+
+
+/* perform a HTTP GET request via SSL/TLS */
+static int
+test_secure_get (FILE *test_fd,
+                 const char *cipher_suite,
+                 int proto_version)
+{
+  int ret;
+  struct MHD_Daemon *d;
+  int port;
+
+  if (MHD_NO != MHD_is_feature_supported (MHD_FEATURE_AUTODETECT_BIND_PORT))
+    port = 0;
+  else
+    port = 3041;
+
+  d = MHD_start_daemon (MHD_USE_THREAD_PER_CONNECTION
+                        | MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_TLS
+                        | MHD_USE_ERROR_LOG, port,
+                        NULL, NULL,
+                        &iovec_ahc, NULL,
+                        MHD_OPTION_HTTPS_MEM_KEY, srv_signed_key_pem,
+                        MHD_OPTION_HTTPS_MEM_CERT, srv_signed_cert_pem,
+                        MHD_OPTION_END);
+
+  if (d == NULL)
+  {
+    fprintf (stderr, MHD_E_SERVER_INIT);
+    return -1;
+  }
+  if (0 == port)
+  {
+    const union MHD_DaemonInfo *dinfo;
+    dinfo = MHD_get_daemon_info (d, MHD_DAEMON_INFO_BIND_PORT);
+    if ((NULL == dinfo) || (0 == dinfo->port) )
+    {
+      MHD_stop_daemon (d); return -1;
+    }
+    port = (int) dinfo->port;
+  }
+
+  ret = test_iovec_transfer (test_fd,
+                             port,
+                             cipher_suite,
+                             proto_version);
+
+  MHD_stop_daemon (d);
+  return ret;
+}
+
+
+static enum MHD_Result
+ahc_empty (void *cls,
+           struct MHD_Connection *connection,
+           const char *url,
+           const char *method,
+           const char *version,
+           const char *upload_data,
+           size_t *upload_data_size,
+           void **unused)
+{
+  static int ptr;
+  struct MHD_Response *response;
+  enum MHD_Result ret;
+  struct MHD_IoVec iov;
+  (void) cls;
+  (void) url;
+  (void) url;
+  (void) version;          /* Unused. Silent compiler warning. */
+  (void) upload_data;
+  (void) upload_data_size; /* Unused. Silent compiler warning. */
+
+  if (0 != strcasecmp ("GET",
+                       method))
+    return MHD_NO;              /* unexpected method */
+  if (&ptr != *unused)
+  {
+    *unused = &ptr;
+    return MHD_YES;
+  }
+  *unused = NULL;
+
+  iov.iov_base = NULL;
+  iov.iov_len = 0;
+
+  response = MHD_create_response_from_iovec (&iov,
+                                             1,
+                                             NULL,
+                                             NULL);
+  ret = MHD_queue_response (connection,
+                            MHD_HTTP_OK,
+                            response);
+  MHD_destroy_response (response);
+  if (ret == MHD_NO)
+  {
+    fprintf (stderr, "Failed to queue response.\n");
+    _exit (20);
+  }
+  return ret;
+}
+
+
+static int
+curlExcessFound (CURL *c,
+                 curl_infotype type,
+                 char *data,
+                 size_t size,
+                 void *cls)
+{
+  static const char *excess_found = "Excess found";
+  const size_t str_size = strlen (excess_found);
+  (void) c;      /* Unused. Silence compiler warning. */
+
+  if ((CURLINFO_TEXT == type)
+      && (size >= str_size)
+      && (0 == strncmp (excess_found, data, str_size)))
+    *(int *) cls = 1;
+  return 0;
+}
+
+
+static int
+testEmptyGet (int poll_flag)
+{
+  struct MHD_Daemon *d;
+  CURL *c;
+  char buf[2048];
+  struct CBC cbc;
+  CURLcode errornum;
+  int excess_found = 0;
+
+
+  if ( (0 == global_port) &&
+       (MHD_NO == MHD_is_feature_supported (MHD_FEATURE_AUTODETECT_BIND_PORT)) )
+  {
+    global_port = 1225;
+
+  }
+
+  cbc.buf = buf;
+  cbc.size = 2048;
+  cbc.pos = 0;
+  d = MHD_start_daemon (MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_ERROR_LOG
+                        | poll_flag | MHD_USE_TLS,
+                        global_port, NULL, NULL,
+                        &ahc_empty, NULL,
+                        MHD_OPTION_HTTPS_MEM_KEY, srv_signed_key_pem,
+                        MHD_OPTION_HTTPS_MEM_CERT, srv_signed_cert_pem,
+                        MHD_OPTION_END);
+  if (d == NULL)
+    return 4194304;
+  if (0 == global_port)
+  {
+    const union MHD_DaemonInfo *dinfo;
+    dinfo = MHD_get_daemon_info (d, MHD_DAEMON_INFO_BIND_PORT);
+    if ((NULL == dinfo) || (0 == dinfo->port) )
+    {
+      MHD_stop_daemon (d); return 32;
+    }
+    global_port = (int) dinfo->port;
+  }
+  c = curl_easy_init ();
+  curl_easy_setopt (c, CURLOPT_URL, "https://127.0.0.1/");
+  curl_easy_setopt (c, CURLOPT_PORT, (long) global_port);
+  curl_easy_setopt (c, CURLOPT_WRITEFUNCTION, &copyBuffer);
+  curl_easy_setopt (c, CURLOPT_WRITEDATA, &cbc);
+  curl_easy_setopt (c, CURLOPT_DEBUGFUNCTION, &curlExcessFound);
+  curl_easy_setopt (c, CURLOPT_DEBUGDATA, &excess_found);
+  curl_easy_setopt (c, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt (c, CURLOPT_FAILONERROR, 1L);
+  curl_easy_setopt (c, CURLOPT_TIMEOUT, 150L);
+  curl_easy_setopt (c, CURLOPT_CONNECTTIMEOUT, 150L);
+  curl_easy_setopt (c, CURLOPT_SSL_VERIFYPEER, 0L);
+  curl_easy_setopt (c, CURLOPT_SSL_VERIFYHOST, 0L);
+  /* NOTE: use of CONNECTTIMEOUT without also
+     setting NOSIGNAL results in really weird
+     crashes on my system!*/
+  curl_easy_setopt (c, CURLOPT_NOSIGNAL, 1L);
+  if (CURLE_OK != (errornum = curl_easy_perform (c)))
+  {
+    fprintf (stderr,
+             "curl_easy_perform failed: `%s'\n",
+             curl_easy_strerror (errornum));
+    curl_easy_cleanup (c);
+    MHD_stop_daemon (d);
+    return 8388608;
+  }
+  curl_easy_cleanup (c);
+  MHD_stop_daemon (d);
+  if (cbc.pos != 0)
+    return 16777216;
+  if (excess_found)
+    return 33554432;
+  return 0;
+}
+
+
+int
+main (int argc, char *const *argv)
+{
+  unsigned int errorCount = 0;
+  const char *aes256_sha_tlsv1   = "AES256-SHA";
+  (void) argc; (void) argv;   /* Unused. Silent compiler warning. */
+
+#ifdef MHD_HTTPS_REQUIRE_GRYPT
+  gcry_control (GCRYCTL_ENABLE_QUICK_RANDOM, 0);
+#ifdef GCRYCTL_INITIALIZATION_FINISHED
+  gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
+#endif
+#endif /* MHD_HTTPS_REQUIRE_GRYPT */
+  if (! testsuite_curl_global_init ())
+    return 99;
+  if (NULL == curl_version_info (CURLVERSION_NOW)->ssl_version)
+  {
+    fprintf (stderr, "Curl does not support SSL.  Cannot run the test.\n");
+    curl_global_cleanup ();
+    return 77;
+  }
+
+  if (curl_uses_nss_ssl () == 0)
+  {
+    aes256_sha_tlsv1 = "rsa_aes_256_sha";
+  }
+  errorCount +=
+    test_secure_get (NULL, aes256_sha_tlsv1, CURL_SSLVERSION_TLSv1);
+  errorCount += testEmptyGet (0);
+  curl_global_cleanup ();
+
+  return errorCount != 0 ? 1 : 0;
+}

src/testcurl/test_get_iovec.c

@@ -0,0 +1,757 @@
+/*
+     This file is part of libmicrohttpd
+     Copyright (C) 2007-2021 Christian Grothoff
+     Copyright (C) 2014-2021 Evgeny Grin
+
+     libmicrohttpd is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 2, or (at your
+     option) any later version.
+
+     libmicrohttpd is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with libmicrohttpd; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+     Boston, MA 02110-1301, USA.
+*/
+
+/**
+ * @file test_get_iovec.c
+ * @brief  Testcase for libmicrohttpd response from scatter/gather array
+ * @author Christian Grothoff
+ * @author Karlson2k (Evgeny Grin)
+ * @author Lawrence Sebald
+ */
+
+/*
+ * This test is largely derived from the test_get_sendfile.c file, with the
+ * daemon using MHD_create_response_from_iovec instead of working from an fd.
+ */
+
+#include "MHD_config.h"
+#include "platform.h"
+#include <curl/curl.h>
+#include <microhttpd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include "mhd_sockets.h"
+#include "mhd_has_in_name.h"
+
+#ifndef WINDOWS
+#include <sys/socket.h>
+#include <unistd.h>
+#endif
+
+#if defined(MHD_CPU_COUNT) && (MHD_CPU_COUNT + 0) < 2
+#undef MHD_CPU_COUNT
+#endif
+#if ! defined(MHD_CPU_COUNT)
+#define MHD_CPU_COUNT 2
+#endif
+
+#define TESTSTR_IOVLEN 20480
+#define TESTSTR_IOVCNT 20
+#define TESTSTR_SIZE   (TESTSTR_IOVCNT * TESTSTR_IOVLEN)
+
+static int oneone;
+
+static int readbuf[TESTSTR_SIZE * 2 / sizeof(int)];
+
+struct CBC
+{
+  char *buf;
+  size_t pos;
+  size_t size;
+};
+
+
+static size_t
+copyBuffer (void *ptr, size_t size, size_t nmemb, void *ctx)
+{
+  struct CBC *cbc = ctx;
+
+  if (cbc->pos + size * nmemb > cbc->size)
+    _exit (7);                   /* overflow */
+  memcpy (&cbc->buf[cbc->pos], ptr, size * nmemb);
+  cbc->pos += size * nmemb;
+  return size * nmemb;
+}
+
+
+static void
+iov_free_callback (void *cls)
+{
+  free (cls);
+}
+
+
+static void
+iovncont_free_callback (void *cls)
+{
+  struct MHD_IoVec *iov = (struct MHD_IoVec *) cls;
+  int i;
+
+  for (i = 0; i < TESTSTR_IOVCNT; ++i)
+  {
+    free (iov[i].iov_base);
+  }
+
+  free (iov);
+}
+
+
+static int
+check_read_data (const void *ptr, size_t len)
+{
+  const int *buf;
+  size_t i;
+
+  if (len % sizeof(int))
+    return -1;
+
+  buf = (const int *) ptr;
+
+  for (i = 0; i < len / sizeof(int); ++i)
+  {
+    if (buf[i] != (int) i)
+      return -1;
+  }
+
+  return 0;
+}
+
+
+static enum MHD_Result
+ahc_echo (void *cls,
+          struct MHD_Connection *connection,
+          const char *url,
+          const char *method,
+          const char *version,
+          const char *upload_data, size_t *upload_data_size,
+          void **unused)
+{
+  static int ptr;
+  const char *me = cls;
+  struct MHD_Response *response;
+  enum MHD_Result ret;
+  int *data;
+  struct MHD_IoVec iov[TESTSTR_IOVCNT];
+  int i;
+  (void) url; (void) version;                      /* Unused. Silent compiler warning. */
+  (void) upload_data; (void) upload_data_size;     /* Unused. Silent compiler warning. */
+
+  if (0 != strcmp (me, method))
+    return MHD_NO;              /* unexpected method */
+  if (&ptr != *unused)
+  {
+    *unused = &ptr;
+    return MHD_YES;
+  }
+  *unused = NULL;
+
+  /* Create some test data. */
+  if (NULL == (data = malloc (TESTSTR_SIZE)))
+    return MHD_NO;
+
+  for (i = 0; i < (int) (TESTSTR_SIZE / sizeof(int)); ++i)
+  {
+    data[i] = i;
+  }
+
+  for (i = 0; i < TESTSTR_IOVCNT; ++i)
+  {
+    iov[i].iov_base = data + (i * (TESTSTR_SIZE / TESTSTR_IOVCNT
+                                   / sizeof(int)));
+    iov[i].iov_len = TESTSTR_SIZE / TESTSTR_IOVCNT;
+  }
+
+  response = MHD_create_response_from_iovec (iov,
+                                             TESTSTR_IOVCNT,
+                                             &iov_free_callback,
+                                             data);
+  ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
+  MHD_destroy_response (response);
+  if (ret == MHD_NO)
+    abort ();
+  return ret;
+}
+
+
+static enum MHD_Result
+ncont_echo (void *cls,
+            struct MHD_Connection *connection,
+            const char *url,
+            const char *method,
+            const char *version,
+            const char *upload_data, size_t *upload_data_size,
+            void **unused)
+{
+  static int ptr;
+  const char *me = cls;
+  struct MHD_Response *response;
+  enum MHD_Result ret;
+  int *data;
+  struct MHD_IoVec *iov;
+  int i, j;
+  (void) url; (void) version;                      /* Unused. Silent compiler warning. */
+  (void) upload_data; (void) upload_data_size;     /* Unused. Silent compiler warning. */
+
+  if (0 != strcmp (me, method))
+    return MHD_NO;              /* unexpected method */
+  if (&ptr != *unused)
+  {
+    *unused = &ptr;
+    return MHD_YES;
+  }
+  *unused = NULL;
+
+  if (NULL == (iov = malloc (sizeof(struct MHD_IoVec) * TESTSTR_IOVCNT)))
+    return MHD_NO;
+
+  memset (iov, 0, sizeof(struct MHD_IoVec) * TESTSTR_IOVCNT);
+
+  /* Create some test data. */
+  for (j = TESTSTR_IOVCNT - 1; j >= 0; --j)
+  {
+    if (NULL == (data = malloc (TESTSTR_IOVLEN)))
+      goto err_out;
+
+    iov[j].iov_base = data;
+    iov[j].iov_len = TESTSTR_IOVLEN;
+
+    for (i = 0; i < (int) (TESTSTR_IOVLEN / sizeof(int)); ++i)
+    {
+      data[i] = i + (j * TESTSTR_IOVLEN / sizeof(int));
+    }
+  }
+
+  response = MHD_create_response_from_iovec (iov,
+                                             TESTSTR_IOVCNT,
+                                             &iovncont_free_callback,
+                                             iov);
+  ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
+  MHD_destroy_response (response);
+  if (ret == MHD_NO)
+    abort ();
+  return ret;
+
+err_out:
+  for (j = 0; j < TESTSTR_IOVCNT; ++j)
+  {
+    if (NULL != iov[j].iov_base)
+      free (iov[j].iov_base);
+  }
+
+  return MHD_NO;
+}
+
+
+static int
+testInternalGet (bool contiguous)
+{
+  struct MHD_Daemon *d;
+  CURL *c;
+  struct CBC cbc;
+  CURLcode errornum;
+  int port;
+
+  if (MHD_NO != MHD_is_feature_supported (MHD_FEATURE_AUTODETECT_BIND_PORT))
+    port = 0;
+  else
+  {
+    port = 1200;
+    if (oneone)
+      port += 10;
+  }
+
+  cbc.buf = (char*) readbuf;
+  cbc.size = sizeof(readbuf);
+  cbc.pos = 0;
+
+  if (contiguous)
+  {
+    d = MHD_start_daemon (MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_ERROR_LOG,
+                          port, NULL, NULL, &ahc_echo, "GET", MHD_OPTION_END);
+  }
+  else
+  {
+    d = MHD_start_daemon (MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_ERROR_LOG,
+                          port, NULL, NULL, &ncont_echo, "GET", MHD_OPTION_END);
+  }
+
+  if (d == NULL)
+    return 1;
+  if (0 == port)
+  {
+    const union MHD_DaemonInfo *dinfo;
+    dinfo = MHD_get_daemon_info (d, MHD_DAEMON_INFO_BIND_PORT);
+    if ((NULL == dinfo) || (0 == dinfo->port) )
+    {
+      MHD_stop_daemon (d); return 32;
+    }
+    port = (int) dinfo->port;
+  }
+  c = curl_easy_init ();
+  curl_easy_setopt (c, CURLOPT_URL, "http://127.0.0.1/");
+  curl_easy_setopt (c, CURLOPT_PORT, (long) port);
+  curl_easy_setopt (c, CURLOPT_WRITEFUNCTION, &copyBuffer);
+  curl_easy_setopt (c, CURLOPT_WRITEDATA, &cbc);
+  curl_easy_setopt (c, CURLOPT_FAILONERROR, 1L);
+  curl_easy_setopt (c, CURLOPT_TIMEOUT, 150L);
+  curl_easy_setopt (c, CURLOPT_CONNECTTIMEOUT, 150L);
+  if (oneone)
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
+  else
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0);
+  /* NOTE: use of CONNECTTIMEOUT without also
+     setting NOSIGNAL results in really weird
+     crashes on my system!*/
+  curl_easy_setopt (c, CURLOPT_NOSIGNAL, 1L);
+  if (CURLE_OK != (errornum = curl_easy_perform (c)))
+  {
+    fprintf (stderr,
+             "curl_easy_perform failed: `%s'\n",
+             curl_easy_strerror (errornum));
+    curl_easy_cleanup (c);
+    MHD_stop_daemon (d);
+    return 2;
+  }
+  curl_easy_cleanup (c);
+  MHD_stop_daemon (d);
+  if (cbc.pos != TESTSTR_SIZE)
+    return 4;
+  if (0 != check_read_data (cbc.buf, cbc.pos))
+    return 8;
+  return 0;
+}
+
+
+static int
+testMultithreadedGet ()
+{
+  struct MHD_Daemon *d;
+  CURL *c;
+  struct CBC cbc;
+  CURLcode errornum;
+  int port;
+
+  if (MHD_NO != MHD_is_feature_supported (MHD_FEATURE_AUTODETECT_BIND_PORT))
+    port = 0;
+  else
+  {
+    port = 1201;
+    if (oneone)
+      port += 10;
+  }
+
+  cbc.buf = (char*) readbuf;
+  cbc.size = sizeof(readbuf);
+  cbc.pos = 0;
+  d = MHD_start_daemon (MHD_USE_THREAD_PER_CONNECTION
+                        | MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_ERROR_LOG
+                        | MHD_USE_AUTO,
+                        port, NULL, NULL, &ahc_echo, "GET", MHD_OPTION_END);
+  if (d == NULL)
+    return 16;
+  if (0 == port)
+  {
+    const union MHD_DaemonInfo *dinfo;
+    dinfo = MHD_get_daemon_info (d, MHD_DAEMON_INFO_BIND_PORT);
+    if ((NULL == dinfo) || (0 == dinfo->port) )
+    {
+      MHD_stop_daemon (d); return 32;
+    }
+    port = (int) dinfo->port;
+  }
+  c = curl_easy_init ();
+  curl_easy_setopt (c, CURLOPT_URL, "http://127.0.0.1/");
+  curl_easy_setopt (c, CURLOPT_PORT, (long) port);
+  curl_easy_setopt (c, CURLOPT_WRITEFUNCTION, &copyBuffer);
+  curl_easy_setopt (c, CURLOPT_WRITEDATA, &cbc);
+  curl_easy_setopt (c, CURLOPT_FAILONERROR, 1L);
+  curl_easy_setopt (c, CURLOPT_TIMEOUT, 150L);
+  if (oneone)
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
+  else
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0);
+  curl_easy_setopt (c, CURLOPT_CONNECTTIMEOUT, 150L);
+  /* NOTE: use of CONNECTTIMEOUT without also
+     setting NOSIGNAL results in really weird
+     crashes on my system! */
+  curl_easy_setopt (c, CURLOPT_NOSIGNAL, 1L);
+  if (CURLE_OK != (errornum = curl_easy_perform (c)))
+  {
+    fprintf (stderr,
+             "curl_easy_perform failed: `%s'\n",
+             curl_easy_strerror (errornum));
+    curl_easy_cleanup (c);
+    MHD_stop_daemon (d);
+    return 32;
+  }
+  curl_easy_cleanup (c);
+  MHD_stop_daemon (d);
+  if (cbc.pos != TESTSTR_SIZE)
+    return 64;
+  if (0 != check_read_data (cbc.buf, cbc.pos))
+    return 128;
+  return 0;
+}
+
+
+static int
+testMultithreadedPoolGet ()
+{
+  struct MHD_Daemon *d;
+  CURL *c;
+  struct CBC cbc;
+  CURLcode errornum;
+  int port;
+
+  if (MHD_NO != MHD_is_feature_supported (MHD_FEATURE_AUTODETECT_BIND_PORT))
+    port = 0;
+  else
+  {
+    port = 1202;
+    if (oneone)
+      port += 10;
+  }
+
+  cbc.buf = (char*) readbuf;
+  cbc.size = sizeof(readbuf);
+  cbc.pos = 0;
+  d = MHD_start_daemon (MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_ERROR_LOG
+                        | MHD_USE_AUTO,
+                        port, NULL, NULL, &ahc_echo, "GET",
+                        MHD_OPTION_THREAD_POOL_SIZE, MHD_CPU_COUNT,
+                        MHD_OPTION_END);
+  if (d == NULL)
+    return 16;
+  if (0 == port)
+  {
+    const union MHD_DaemonInfo *dinfo;
+    dinfo = MHD_get_daemon_info (d, MHD_DAEMON_INFO_BIND_PORT);
+    if ((NULL == dinfo) || (0 == dinfo->port) )
+    {
+      MHD_stop_daemon (d); return 32;
+    }
+    port = (int) dinfo->port;
+  }
+  c = curl_easy_init ();
+  curl_easy_setopt (c, CURLOPT_URL, "http://127.0.0.1/");
+  curl_easy_setopt (c, CURLOPT_PORT, (long) port);
+  curl_easy_setopt (c, CURLOPT_WRITEFUNCTION, &copyBuffer);
+  curl_easy_setopt (c, CURLOPT_WRITEDATA, &cbc);
+  curl_easy_setopt (c, CURLOPT_FAILONERROR, 1L);
+  curl_easy_setopt (c, CURLOPT_TIMEOUT, 150L);
+  if (oneone)
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
+  else
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0);
+  curl_easy_setopt (c, CURLOPT_CONNECTTIMEOUT, 150L);
+  /* NOTE: use of CONNECTTIMEOUT without also
+     setting NOSIGNAL results in really weird
+     crashes on my system!*/
+  curl_easy_setopt (c, CURLOPT_NOSIGNAL, 1L);
+  if (CURLE_OK != (errornum = curl_easy_perform (c)))
+  {
+    fprintf (stderr,
+             "curl_easy_perform failed: `%s'\n",
+             curl_easy_strerror (errornum));
+    curl_easy_cleanup (c);
+    MHD_stop_daemon (d);
+    return 32;
+  }
+  curl_easy_cleanup (c);
+  MHD_stop_daemon (d);
+  if (cbc.pos != TESTSTR_SIZE)
+    return 64;
+  if (0 != check_read_data (cbc.buf, cbc.pos))
+    return 128;
+  return 0;
+}
+
+
+static int
+testExternalGet ()
+{
+  struct MHD_Daemon *d;
+  CURL *c;
+  struct CBC cbc;
+  CURLM *multi;
+  CURLMcode mret;
+  fd_set rs;
+  fd_set ws;
+  fd_set es;
+  MHD_socket maxsock;
+#ifdef MHD_WINSOCK_SOCKETS
+  int maxposixs; /* Max socket number unused on W32 */
+#else  /* MHD_POSIX_SOCKETS */
+#define maxposixs maxsock
+#endif /* MHD_POSIX_SOCKETS */
+  int running;
+  struct CURLMsg *msg;
+  time_t start;
+  struct timeval tv;
+  int port;
+
+  if (MHD_NO != MHD_is_feature_supported (MHD_FEATURE_AUTODETECT_BIND_PORT))
+    port = 0;
+  else
+  {
+    port = 1203;
+    if (oneone)
+      port += 10;
+  }
+
+  multi = NULL;
+  cbc.buf = (char*) readbuf;
+  cbc.size = sizeof(readbuf);
+  cbc.pos = 0;
+  d = MHD_start_daemon (MHD_USE_ERROR_LOG,
+                        port, NULL, NULL, &ahc_echo, "GET", MHD_OPTION_END);
+  if (d == NULL)
+    return 256;
+  if (0 == port)
+  {
+    const union MHD_DaemonInfo *dinfo;
+    dinfo = MHD_get_daemon_info (d, MHD_DAEMON_INFO_BIND_PORT);
+    if ((NULL == dinfo) || (0 == dinfo->port) )
+    {
+      MHD_stop_daemon (d); return 32;
+    }
+    port = (int) dinfo->port;
+  }
+  c = curl_easy_init ();
+  curl_easy_setopt (c, CURLOPT_URL, "http://127.0.0.1/");
+  curl_easy_setopt (c, CURLOPT_PORT, (long) port);
+  curl_easy_setopt (c, CURLOPT_WRITEFUNCTION, &copyBuffer);
+  curl_easy_setopt (c, CURLOPT_WRITEDATA, &cbc);
+  curl_easy_setopt (c, CURLOPT_FAILONERROR, 1L);
+  if (oneone)
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
+  else
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0);
+  curl_easy_setopt (c, CURLOPT_TIMEOUT, 150L);
+  curl_easy_setopt (c, CURLOPT_CONNECTTIMEOUT, 150L);
+  /* NOTE: use of CONNECTTIMEOUT without also
+     setting NOSIGNAL results in really weird
+     crashes on my system! */
+  curl_easy_setopt (c, CURLOPT_NOSIGNAL, 1L);
+
+
+  multi = curl_multi_init ();
+  if (multi == NULL)
+  {
+    curl_easy_cleanup (c);
+    MHD_stop_daemon (d);
+    return 512;
+  }
+  mret = curl_multi_add_handle (multi, c);
+  if (mret != CURLM_OK)
+  {
+    curl_multi_cleanup (multi);
+    curl_easy_cleanup (c);
+    MHD_stop_daemon (d);
+    return 1024;
+  }
+  start = time (NULL);
+  while ((time (NULL) - start < 5) && (multi != NULL))
+  {
+    maxsock = MHD_INVALID_SOCKET;
+    maxposixs = -1;
+    FD_ZERO (&rs);
+    FD_ZERO (&ws);
+    FD_ZERO (&es);
+    curl_multi_perform (multi, &running);
+    mret = curl_multi_fdset (multi, &rs, &ws, &es, &maxposixs);
+    if (mret != CURLM_OK)
+    {
+      curl_multi_remove_handle (multi, c);
+      curl_multi_cleanup (multi);
+      curl_easy_cleanup (c);
+      MHD_stop_daemon (d);
+      return 2048;
+    }
+    if (MHD_YES != MHD_get_fdset (d, &rs, &ws, &es, &maxsock))
+    {
+      curl_multi_remove_handle (multi, c);
+      curl_multi_cleanup (multi);
+      curl_easy_cleanup (c);
+      MHD_stop_daemon (d);
+      return 4096;
+    }
+    tv.tv_sec = 0;
+    tv.tv_usec = 1000;
+    if (-1 == select (maxposixs + 1, &rs, &ws, &es, &tv))
+    {
+#ifdef MHD_POSIX_SOCKETS
+      if (EINTR != errno)
+        abort ();
+#else
+      if ((WSAEINVAL != WSAGetLastError ()) || (0 != rs.fd_count) || (0 !=
+                                                                      ws.
+                                                                      fd_count)
+          || (0 != es.fd_count) )
+        abort ();
+      Sleep (1000);
+#endif
+    }
+    curl_multi_perform (multi, &running);
+    if (running == 0)
+    {
+      msg = curl_multi_info_read (multi, &running);
+      if (msg == NULL)
+        break;
+      if (msg->msg == CURLMSG_DONE)
+      {
+        if (msg->data.result != CURLE_OK)
+          printf ("%s failed at %s:%d: `%s'\n",
+                  "curl_multi_perform",
+                  __FILE__,
+                  __LINE__, curl_easy_strerror (msg->data.result));
+        curl_multi_remove_handle (multi, c);
+        curl_multi_cleanup (multi);
+        curl_easy_cleanup (c);
+        c = NULL;
+        multi = NULL;
+      }
+    }
+    MHD_run (d);
+  }
+  if (multi != NULL)
+  {
+    curl_multi_remove_handle (multi, c);
+    curl_easy_cleanup (c);
+    curl_multi_cleanup (multi);
+  }
+  MHD_stop_daemon (d);
+  if (cbc.pos != TESTSTR_SIZE)
+    return 8192;
+  if (0 != check_read_data (cbc.buf, cbc.pos))
+    return 16384;
+  return 0;
+}
+
+
+static int
+testUnknownPortGet ()
+{
+  struct MHD_Daemon *d;
+  const union MHD_DaemonInfo *di;
+  CURL *c;
+  struct CBC cbc;
+  CURLcode errornum;
+  int port;
+  char buf[2048];
+
+  struct sockaddr_in addr;
+  socklen_t addr_len = sizeof(addr);
+  memset (&addr, 0, sizeof(addr));
+  addr.sin_family = AF_INET;
+  addr.sin_port = 0;
+  addr.sin_addr.s_addr = INADDR_ANY;
+
+  cbc.buf = (char*) readbuf;
+  cbc.size = sizeof(readbuf);
+  cbc.pos = 0;
+  d = MHD_start_daemon (MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_ERROR_LOG,
+                        0, NULL, NULL, &ahc_echo, "GET",
+                        MHD_OPTION_SOCK_ADDR, &addr,
+                        MHD_OPTION_END);
+  if (d == NULL)
+    return 32768;
+
+  if (MHD_NO == MHD_is_feature_supported (MHD_FEATURE_AUTODETECT_BIND_PORT))
+  {
+    di = MHD_get_daemon_info (d, MHD_DAEMON_INFO_LISTEN_FD);
+    if (di == NULL)
+      return 65536;
+
+    if (0 != getsockname (di->listen_fd, (struct sockaddr *) &addr, &addr_len))
+      return 131072;
+
+    if (addr.sin_family != AF_INET)
+      return 26214;
+    port = (int) ntohs (addr.sin_port);
+  }
+  else
+  {
+    const union MHD_DaemonInfo *dinfo;
+    dinfo = MHD_get_daemon_info (d, MHD_DAEMON_INFO_BIND_PORT);
+    if ((NULL == dinfo) || (0 == dinfo->port) )
+    {
+      MHD_stop_daemon (d); return 32;
+    }
+    port = (int) dinfo->port;
+  }
+
+  snprintf (buf, sizeof(buf), "http://127.0.0.1:%d/",
+            port);
+
+  c = curl_easy_init ();
+  curl_easy_setopt (c, CURLOPT_URL, buf);
+  curl_easy_setopt (c, CURLOPT_WRITEFUNCTION, &copyBuffer);
+  curl_easy_setopt (c, CURLOPT_WRITEDATA, &cbc);
+  curl_easy_setopt (c, CURLOPT_FAILONERROR, 1L);
+  curl_easy_setopt (c, CURLOPT_TIMEOUT, 150L);
+  curl_easy_setopt (c, CURLOPT_CONNECTTIMEOUT, 150L);
+  if (oneone)
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
+  else
+    curl_easy_setopt (c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0);
+  /* NOTE: use of CONNECTTIMEOUT without also
+     setting NOSIGNAL results in really weird
+     crashes on my system! */
+  curl_easy_setopt (c, CURLOPT_NOSIGNAL, 1L);
+  if (CURLE_OK != (errornum = curl_easy_perform (c)))
+  {
+    fprintf (stderr,
+             "curl_easy_perform failed: `%s'\n",
+             curl_easy_strerror (errornum));
+    curl_easy_cleanup (c);
+    MHD_stop_daemon (d);
+    return 524288;
+  }
+  curl_easy_cleanup (c);
+  MHD_stop_daemon (d);
+  if (cbc.pos != TESTSTR_SIZE)
+    return 1048576;
+  if (0 != check_read_data (cbc.buf, cbc.pos))
+    return 2097152;
+  return 0;
+}
+
+
+int
+main (int argc, char *const *argv)
+{
+  unsigned int errorCount = 0;
+  (void) argc;   /* Unused. Silent compiler warning. */
+
+  if ((NULL == argv) || (0 == argv[0]))
+    return 99;
+  oneone = has_in_name (argv[0], "11");
+
+  if (0 != curl_global_init (CURL_GLOBAL_WIN32))
+    return 2;
+  if (MHD_YES == MHD_is_feature_supported (MHD_FEATURE_THREADS))
+  {
+    errorCount += testInternalGet (true);
+    errorCount += testInternalGet (false);
+    errorCount += testMultithreadedGet ();
+    errorCount += testMultithreadedPoolGet ();
+    errorCount += testUnknownPortGet ();
+  }
+  errorCount += testExternalGet ();
+  if (errorCount != 0)
+    fprintf (stderr, "Error (code: %u)\n", errorCount);
+  curl_global_cleanup ();
+  return errorCount != 0;       /* 0 == pass */
+}