Initial check in of curl.

Plan to:
- Fix warnings
- Add java support

Change-Id: Ia61d4d479aa61178f2883161491ab844301317e0
diff --git a/lib/telnet.c b/lib/telnet.c
new file mode 100644
index 0000000..9409f49
--- /dev/null
+++ b/lib/telnet.c
@@ -0,0 +1,1519 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2010, 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 http://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.
+ *
+ ***************************************************************************/
+
+#include "setup.h"
+
+#ifndef CURL_DISABLE_TELNET
+/* -- WIN32 approved -- */
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <ctype.h>
+
+#if defined(WIN32)
+#include <time.h>
+#include <io.h>
+#else
+#ifdef HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+#include <netinet/in.h>
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <netdb.h>
+#ifdef HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+#ifdef HAVE_NET_IF_H
+#include <net/if.h>
+#endif
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+
+#ifdef HAVE_SYS_PARAM_H
+#include <sys/param.h>
+#endif
+
+#endif  /* WIN32 */
+
+#include "urldata.h"
+#include <curl/curl.h>
+#include "transfer.h"
+#include "sendf.h"
+#include "telnet.h"
+#include "connect.h"
+
+#define _MPRINTF_REPLACE /* use our functions only */
+#include <curl/mprintf.h>
+
+#define  TELOPTS
+#define  TELCMDS
+
+#include "arpa_telnet.h"
+#include "curl_memory.h"
+#include "select.h"
+#include "strequal.h"
+#include "rawstr.h"
+
+/* The last #include file should be: */
+#include "memdebug.h"
+
+#define SUBBUFSIZE 512
+
+#define CURL_SB_CLEAR(x)  x->subpointer = x->subbuffer;
+#define CURL_SB_TERM(x)   { x->subend = x->subpointer; CURL_SB_CLEAR(x); }
+#define CURL_SB_ACCUM(x,c) \
+  if(x->subpointer < (x->subbuffer+sizeof x->subbuffer)) { \
+    *x->subpointer++ = (c); \
+  }
+
+#define  CURL_SB_GET(x) ((*x->subpointer++)&0xff)
+#define  CURL_SB_PEEK(x)   ((*x->subpointer)&0xff)
+#define  CURL_SB_EOF(x) (x->subpointer >= x->subend)
+#define  CURL_SB_LEN(x) (x->subend - x->subpointer)
+
+#ifdef CURL_DISABLE_VERBOSE_STRINGS
+#define printoption(a,b,c,d)  do { } while(0)
+#endif
+
+#ifdef USE_WINSOCK
+typedef FARPROC WSOCK2_FUNC;
+static CURLcode check_wsock2 ( struct SessionHandle *data );
+#endif
+
+static
+CURLcode telrcv(struct connectdata *,
+                const unsigned char *inbuf, /* Data received from socket */
+                ssize_t count);             /* Number of bytes received */
+
+#ifndef CURL_DISABLE_VERBOSE_STRINGS
+static void printoption(struct SessionHandle *data,
+                        const char *direction,
+                        int cmd, int option);
+#endif
+
+static void negotiate(struct connectdata *);
+static void send_negotiation(struct connectdata *, int cmd, int option);
+static void set_local_option(struct connectdata *, int cmd, int option);
+static void set_remote_option(struct connectdata *, int cmd, int option);
+
+static void printsub(struct SessionHandle *data,
+                     int direction, unsigned char *pointer,
+                     size_t length);
+static void suboption(struct connectdata *);
+
+static CURLcode telnet_do(struct connectdata *conn, bool *done);
+static CURLcode telnet_done(struct connectdata *conn,
+                                 CURLcode, bool premature);
+
+/* For negotiation compliant to RFC 1143 */
+#define CURL_NO          0
+#define CURL_YES         1
+#define CURL_WANTYES     2
+#define CURL_WANTNO      3
+
+#define CURL_EMPTY       0
+#define CURL_OPPOSITE    1
+
+/*
+ * Telnet receiver states for fsm
+ */
+typedef enum
+{
+   CURL_TS_DATA = 0,
+   CURL_TS_IAC,
+   CURL_TS_WILL,
+   CURL_TS_WONT,
+   CURL_TS_DO,
+   CURL_TS_DONT,
+   CURL_TS_CR,
+   CURL_TS_SB,   /* sub-option collection */
+   CURL_TS_SE   /* looking for sub-option end */
+} TelnetReceive;
+
+struct TELNET {
+  int please_negotiate;
+  int already_negotiated;
+  int us[256];
+  int usq[256];
+  int us_preferred[256];
+  int him[256];
+  int himq[256];
+  int him_preferred[256];
+  char subopt_ttype[32];             /* Set with suboption TTYPE */
+  char subopt_xdisploc[128];          /* Set with suboption XDISPLOC */
+  struct curl_slist *telnet_vars; /* Environment variables */
+
+  /* suboptions */
+  unsigned char subbuffer[SUBBUFSIZE];
+  unsigned char *subpointer, *subend;      /* buffer for sub-options */
+
+  TelnetReceive telrcv_state;
+};
+
+
+/*
+ * TELNET protocol handler.
+ */
+
+const struct Curl_handler Curl_handler_telnet = {
+  "TELNET",                             /* scheme */
+  ZERO_NULL,                            /* setup_connection */
+  telnet_do,                            /* do_it */
+  telnet_done,                          /* done */
+  ZERO_NULL,                            /* do_more */
+  ZERO_NULL,                            /* connect_it */
+  ZERO_NULL,                            /* connecting */
+  ZERO_NULL,                            /* doing */
+  ZERO_NULL,                            /* proto_getsock */
+  ZERO_NULL,                            /* doing_getsock */
+  ZERO_NULL,                            /* perform_getsock */
+  ZERO_NULL,                            /* disconnect */
+  PORT_TELNET,                          /* defport */
+  PROT_TELNET                           /* protocol */
+};
+
+
+#ifdef USE_WINSOCK
+static CURLcode
+check_wsock2 ( struct SessionHandle *data )
+{
+  int err;
+  WORD wVersionRequested;
+  WSADATA wsaData;
+
+  DEBUGASSERT(data);
+
+  /* telnet requires at least WinSock 2.0 so ask for it. */
+  wVersionRequested = MAKEWORD(2, 0);
+
+  err = WSAStartup(wVersionRequested, &wsaData);
+
+  /* We must've called this once already, so this call */
+  /* should always succeed.  But, just in case... */
+  if(err != 0) {
+    failf(data,"WSAStartup failed (%d)",err);
+    return CURLE_FAILED_INIT;
+  }
+
+  /* We have to have a WSACleanup call for every successful */
+  /* WSAStartup call. */
+  WSACleanup();
+
+  /* Check that our version is supported */
+  if(LOBYTE(wsaData.wVersion) != LOBYTE(wVersionRequested) ||
+      HIBYTE(wsaData.wVersion) != HIBYTE(wVersionRequested)) {
+      /* Our version isn't supported */
+      failf(data,"insufficient winsock version to support "
+            "telnet");
+      return CURLE_FAILED_INIT;
+  }
+
+  /* Our version is supported */
+  return CURLE_OK;
+}
+#endif
+
+static
+CURLcode init_telnet(struct connectdata *conn)
+{
+  struct TELNET *tn;
+
+  tn = calloc(1, sizeof(struct TELNET));
+  if(!tn)
+    return CURLE_OUT_OF_MEMORY;
+
+  conn->data->state.proto.telnet = (void *)tn; /* make us known */
+
+  tn->telrcv_state = CURL_TS_DATA;
+
+  /* Init suboptions */
+  CURL_SB_CLEAR(tn);
+
+  /* Set the options we want by default */
+  tn->us_preferred[CURL_TELOPT_BINARY] = CURL_YES;
+  tn->us_preferred[CURL_TELOPT_SGA] = CURL_YES;
+  tn->him_preferred[CURL_TELOPT_BINARY] = CURL_YES;
+  tn->him_preferred[CURL_TELOPT_SGA] = CURL_YES;
+
+  return CURLE_OK;
+}
+
+static void negotiate(struct connectdata *conn)
+{
+  int i;
+  struct TELNET *tn = (struct TELNET *) conn->data->state.proto.telnet;
+
+  for(i = 0;i < CURL_NTELOPTS;i++)
+  {
+    if(tn->us_preferred[i] == CURL_YES)
+      set_local_option(conn, i, CURL_YES);
+
+    if(tn->him_preferred[i] == CURL_YES)
+      set_remote_option(conn, i, CURL_YES);
+  }
+}
+
+#ifndef CURL_DISABLE_VERBOSE_STRINGS
+static void printoption(struct SessionHandle *data,
+                        const char *direction, int cmd, int option)
+{
+  const char *fmt;
+  const char *opt;
+
+  if(data->set.verbose)
+  {
+    if(cmd == CURL_IAC)
+    {
+      if(CURL_TELCMD_OK(option))
+        infof(data, "%s IAC %s\n", direction, CURL_TELCMD(option));
+      else
+        infof(data, "%s IAC %d\n", direction, option);
+    }
+    else
+    {
+      fmt = (cmd == CURL_WILL) ? "WILL" : (cmd == CURL_WONT) ? "WONT" :
+        (cmd == CURL_DO) ? "DO" : (cmd == CURL_DONT) ? "DONT" : 0;
+      if(fmt)
+      {
+        if(CURL_TELOPT_OK(option))
+          opt = CURL_TELOPT(option);
+        else if(option == CURL_TELOPT_EXOPL)
+          opt = "EXOPL";
+        else
+          opt = NULL;
+
+        if(opt)
+          infof(data, "%s %s %s\n", direction, fmt, opt);
+        else
+          infof(data, "%s %s %d\n", direction, fmt, option);
+      }
+      else
+        infof(data, "%s %d %d\n", direction, cmd, option);
+    }
+  }
+}
+#endif
+
+static void send_negotiation(struct connectdata *conn, int cmd, int option)
+{
+   unsigned char buf[3];
+   ssize_t bytes_written;
+   int err;
+   struct SessionHandle *data = conn->data;
+
+   buf[0] = CURL_IAC;
+   buf[1] = (unsigned char)cmd;
+   buf[2] = (unsigned char)option;
+
+   bytes_written = swrite(conn->sock[FIRSTSOCKET], buf, 3);
+   if(bytes_written < 0) {
+     err = SOCKERRNO;
+     failf(data,"Sending data failed (%d)",err);
+   }
+
+   printoption(conn->data, "SENT", cmd, option);
+}
+
+static
+void set_remote_option(struct connectdata *conn, int option, int newstate)
+{
+  struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet;
+  if(newstate == CURL_YES)
+  {
+    switch(tn->him[option])
+    {
+      case CURL_NO:
+        tn->him[option] = CURL_WANTYES;
+        send_negotiation(conn, CURL_DO, option);
+        break;
+
+      case CURL_YES:
+        /* Already enabled */
+        break;
+
+      case CURL_WANTNO:
+        switch(tn->himq[option])
+        {
+          case CURL_EMPTY:
+            /* Already negotiating for CURL_YES, queue the request */
+            tn->himq[option] = CURL_OPPOSITE;
+            break;
+          case CURL_OPPOSITE:
+            /* Error: already queued an enable request */
+            break;
+        }
+        break;
+
+      case CURL_WANTYES:
+        switch(tn->himq[option])
+        {
+          case CURL_EMPTY:
+            /* Error: already negotiating for enable */
+            break;
+          case CURL_OPPOSITE:
+            tn->himq[option] = CURL_EMPTY;
+            break;
+        }
+        break;
+    }
+  }
+  else /* NO */
+  {
+    switch(tn->him[option])
+    {
+      case CURL_NO:
+        /* Already disabled */
+        break;
+
+      case CURL_YES:
+        tn->him[option] = CURL_WANTNO;
+        send_negotiation(conn, CURL_DONT, option);
+        break;
+
+      case CURL_WANTNO:
+        switch(tn->himq[option])
+        {
+          case CURL_EMPTY:
+            /* Already negotiating for NO */
+            break;
+          case CURL_OPPOSITE:
+            tn->himq[option] = CURL_EMPTY;
+            break;
+        }
+        break;
+
+      case CURL_WANTYES:
+        switch(tn->himq[option])
+        {
+          case CURL_EMPTY:
+            tn->himq[option] = CURL_OPPOSITE;
+            break;
+          case CURL_OPPOSITE:
+            break;
+        }
+        break;
+    }
+  }
+}
+
+static
+void rec_will(struct connectdata *conn, int option)
+{
+  struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet;
+  switch(tn->him[option])
+  {
+    case CURL_NO:
+      if(tn->him_preferred[option] == CURL_YES)
+      {
+        tn->him[option] = CURL_YES;
+        send_negotiation(conn, CURL_DO, option);
+      }
+      else
+      {
+        send_negotiation(conn, CURL_DONT, option);
+      }
+      break;
+
+    case CURL_YES:
+      /* Already enabled */
+      break;
+
+    case CURL_WANTNO:
+      switch(tn->himq[option])
+      {
+        case CURL_EMPTY:
+          /* Error: DONT answered by WILL */
+          tn->him[option] = CURL_NO;
+          break;
+        case CURL_OPPOSITE:
+          /* Error: DONT answered by WILL */
+          tn->him[option] = CURL_YES;
+          tn->himq[option] = CURL_EMPTY;
+          break;
+      }
+      break;
+
+    case CURL_WANTYES:
+      switch(tn->himq[option])
+      {
+        case CURL_EMPTY:
+          tn->him[option] = CURL_YES;
+          break;
+        case CURL_OPPOSITE:
+          tn->him[option] = CURL_WANTNO;
+          tn->himq[option] = CURL_EMPTY;
+          send_negotiation(conn, CURL_DONT, option);
+          break;
+      }
+      break;
+  }
+}
+
+static
+void rec_wont(struct connectdata *conn, int option)
+{
+  struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet;
+  switch(tn->him[option])
+  {
+    case CURL_NO:
+      /* Already disabled */
+      break;
+
+    case CURL_YES:
+      tn->him[option] = CURL_NO;
+      send_negotiation(conn, CURL_DONT, option);
+      break;
+
+    case CURL_WANTNO:
+      switch(tn->himq[option])
+      {
+        case CURL_EMPTY:
+          tn->him[option] = CURL_NO;
+          break;
+
+        case CURL_OPPOSITE:
+          tn->him[option] = CURL_WANTYES;
+          tn->himq[option] = CURL_EMPTY;
+          send_negotiation(conn, CURL_DO, option);
+          break;
+      }
+      break;
+
+    case CURL_WANTYES:
+      switch(tn->himq[option])
+      {
+        case CURL_EMPTY:
+          tn->him[option] = CURL_NO;
+          break;
+        case CURL_OPPOSITE:
+          tn->him[option] = CURL_NO;
+          tn->himq[option] = CURL_EMPTY;
+          break;
+      }
+      break;
+  }
+}
+
+static void
+set_local_option(struct connectdata *conn, int option, int newstate)
+{
+  struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet;
+  if(newstate == CURL_YES)
+  {
+    switch(tn->us[option])
+    {
+      case CURL_NO:
+        tn->us[option] = CURL_WANTYES;
+        send_negotiation(conn, CURL_WILL, option);
+        break;
+
+      case CURL_YES:
+        /* Already enabled */
+        break;
+
+      case CURL_WANTNO:
+        switch(tn->usq[option])
+        {
+          case CURL_EMPTY:
+            /* Already negotiating for CURL_YES, queue the request */
+            tn->usq[option] = CURL_OPPOSITE;
+            break;
+          case CURL_OPPOSITE:
+            /* Error: already queued an enable request */
+            break;
+        }
+        break;
+
+      case CURL_WANTYES:
+        switch(tn->usq[option])
+        {
+          case CURL_EMPTY:
+            /* Error: already negotiating for enable */
+            break;
+          case CURL_OPPOSITE:
+            tn->usq[option] = CURL_EMPTY;
+            break;
+        }
+        break;
+    }
+  }
+  else /* NO */
+  {
+    switch(tn->us[option])
+    {
+      case CURL_NO:
+        /* Already disabled */
+        break;
+
+      case CURL_YES:
+        tn->us[option] = CURL_WANTNO;
+        send_negotiation(conn, CURL_WONT, option);
+        break;
+
+      case CURL_WANTNO:
+        switch(tn->usq[option])
+        {
+          case CURL_EMPTY:
+            /* Already negotiating for NO */
+            break;
+          case CURL_OPPOSITE:
+            tn->usq[option] = CURL_EMPTY;
+            break;
+        }
+        break;
+
+      case CURL_WANTYES:
+        switch(tn->usq[option])
+        {
+          case CURL_EMPTY:
+            tn->usq[option] = CURL_OPPOSITE;
+            break;
+          case CURL_OPPOSITE:
+            break;
+        }
+        break;
+    }
+  }
+}
+
+static
+void rec_do(struct connectdata *conn, int option)
+{
+  struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet;
+  switch(tn->us[option])
+  {
+    case CURL_NO:
+      if(tn->us_preferred[option] == CURL_YES)
+      {
+        tn->us[option] = CURL_YES;
+        send_negotiation(conn, CURL_WILL, option);
+      }
+      else
+      {
+        send_negotiation(conn, CURL_WONT, option);
+      }
+      break;
+
+    case CURL_YES:
+      /* Already enabled */
+      break;
+
+    case CURL_WANTNO:
+      switch(tn->usq[option])
+      {
+        case CURL_EMPTY:
+          /* Error: DONT answered by WILL */
+          tn->us[option] = CURL_NO;
+          break;
+        case CURL_OPPOSITE:
+          /* Error: DONT answered by WILL */
+          tn->us[option] = CURL_YES;
+          tn->usq[option] = CURL_EMPTY;
+          break;
+      }
+      break;
+
+    case CURL_WANTYES:
+      switch(tn->usq[option])
+      {
+        case CURL_EMPTY:
+          tn->us[option] = CURL_YES;
+          break;
+        case CURL_OPPOSITE:
+          tn->us[option] = CURL_WANTNO;
+          tn->himq[option] = CURL_EMPTY;
+          send_negotiation(conn, CURL_WONT, option);
+          break;
+      }
+      break;
+  }
+}
+
+static
+void rec_dont(struct connectdata *conn, int option)
+{
+  struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet;
+  switch(tn->us[option])
+  {
+    case CURL_NO:
+      /* Already disabled */
+      break;
+
+    case CURL_YES:
+      tn->us[option] = CURL_NO;
+      send_negotiation(conn, CURL_WONT, option);
+      break;
+
+    case CURL_WANTNO:
+      switch(tn->usq[option])
+      {
+        case CURL_EMPTY:
+          tn->us[option] = CURL_NO;
+          break;
+
+        case CURL_OPPOSITE:
+          tn->us[option] = CURL_WANTYES;
+          tn->usq[option] = CURL_EMPTY;
+          send_negotiation(conn, CURL_WILL, option);
+          break;
+      }
+      break;
+
+    case CURL_WANTYES:
+      switch(tn->usq[option])
+      {
+        case CURL_EMPTY:
+          tn->us[option] = CURL_NO;
+          break;
+        case CURL_OPPOSITE:
+          tn->us[option] = CURL_NO;
+          tn->usq[option] = CURL_EMPTY;
+          break;
+      }
+      break;
+  }
+}
+
+
+static void printsub(struct SessionHandle *data,
+                     int direction,             /* '<' or '>' */
+                     unsigned char *pointer,    /* where suboption data is */
+                     size_t length)             /* length of suboption data */
+{
+  unsigned int i = 0;
+
+  if(data->set.verbose)
+  {
+    if(direction)
+    {
+      infof(data, "%s IAC SB ", (direction == '<')? "RCVD":"SENT");
+      if(length >= 3)
+      {
+        int j;
+
+        i = pointer[length-2];
+        j = pointer[length-1];
+
+        if(i != CURL_IAC || j != CURL_SE)
+        {
+          infof(data, "(terminated by ");
+          if(CURL_TELOPT_OK(i))
+            infof(data, "%s ", CURL_TELOPT(i));
+          else if(CURL_TELCMD_OK(i))
+            infof(data, "%s ", CURL_TELCMD(i));
+          else
+            infof(data, "%u ", i);
+          if(CURL_TELOPT_OK(j))
+            infof(data, "%s", CURL_TELOPT(j));
+          else if(CURL_TELCMD_OK(j))
+            infof(data, "%s", CURL_TELCMD(j));
+          else
+            infof(data, "%d", j);
+          infof(data, ", not IAC SE!) ");
+        }
+      }
+      length -= 2;
+    }
+    if(length < 1)
+    {
+      infof(data, "(Empty suboption?)");
+      return;
+    }
+
+    if(CURL_TELOPT_OK(pointer[0])) {
+      switch(pointer[0]) {
+        case CURL_TELOPT_TTYPE:
+        case CURL_TELOPT_XDISPLOC:
+        case CURL_TELOPT_NEW_ENVIRON:
+          infof(data, "%s", CURL_TELOPT(pointer[0]));
+          break;
+        default:
+          infof(data, "%s (unsupported)", CURL_TELOPT(pointer[0]));
+          break;
+      }
+    }
+    else
+      infof(data, "%d (unknown)", pointer[i]);
+
+    switch(pointer[1]) {
+      case CURL_TELQUAL_IS:
+        infof(data, " IS");
+        break;
+      case CURL_TELQUAL_SEND:
+        infof(data, " SEND");
+        break;
+      case CURL_TELQUAL_INFO:
+        infof(data, " INFO/REPLY");
+        break;
+      case CURL_TELQUAL_NAME:
+        infof(data, " NAME");
+        break;
+    }
+
+    switch(pointer[0]) {
+      case CURL_TELOPT_TTYPE:
+      case CURL_TELOPT_XDISPLOC:
+        pointer[length] = 0;
+        infof(data, " \"%s\"", &pointer[2]);
+        break;
+      case CURL_TELOPT_NEW_ENVIRON:
+        if(pointer[1] == CURL_TELQUAL_IS) {
+          infof(data, " ");
+          for(i = 3;i < length;i++) {
+            switch(pointer[i]) {
+              case CURL_NEW_ENV_VAR:
+                infof(data, ", ");
+                break;
+              case CURL_NEW_ENV_VALUE:
+                infof(data, " = ");
+                break;
+              default:
+                infof(data, "%c", pointer[i]);
+                break;
+            }
+          }
+        }
+        break;
+      default:
+        for (i = 2; i < length; i++)
+          infof(data, " %.2x", pointer[i]);
+        break;
+    }
+
+    if(direction)
+    {
+      infof(data, "\n");
+    }
+  }
+}
+
+static CURLcode check_telnet_options(struct connectdata *conn)
+{
+  struct curl_slist *head;
+  char option_keyword[128];
+  char option_arg[256];
+  char *buf;
+  struct SessionHandle *data = conn->data;
+  struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet;
+
+  /* Add the user name as an environment variable if it
+     was given on the command line */
+  if(conn->bits.user_passwd)
+  {
+    snprintf(option_arg, sizeof(option_arg), "USER,%s", conn->user);
+    tn->telnet_vars = curl_slist_append(tn->telnet_vars, option_arg);
+
+    tn->us_preferred[CURL_TELOPT_NEW_ENVIRON] = CURL_YES;
+  }
+
+  for(head = data->set.telnet_options; head; head=head->next) {
+    if(sscanf(head->data, "%127[^= ]%*[ =]%255s",
+              option_keyword, option_arg) == 2) {
+
+      /* Terminal type */
+      if(Curl_raw_equal(option_keyword, "TTYPE")) {
+        strncpy(tn->subopt_ttype, option_arg, 31);
+        tn->subopt_ttype[31] = 0; /* String termination */
+        tn->us_preferred[CURL_TELOPT_TTYPE] = CURL_YES;
+        continue;
+      }
+
+      /* Display variable */
+      if(Curl_raw_equal(option_keyword, "XDISPLOC")) {
+        strncpy(tn->subopt_xdisploc, option_arg, 127);
+        tn->subopt_xdisploc[127] = 0; /* String termination */
+        tn->us_preferred[CURL_TELOPT_XDISPLOC] = CURL_YES;
+        continue;
+      }
+
+      /* Environment variable */
+      if(Curl_raw_equal(option_keyword, "NEW_ENV")) {
+        buf = strdup(option_arg);
+        if(!buf)
+          return CURLE_OUT_OF_MEMORY;
+        tn->telnet_vars = curl_slist_append(tn->telnet_vars, buf);
+        tn->us_preferred[CURL_TELOPT_NEW_ENVIRON] = CURL_YES;
+        continue;
+      }
+
+      failf(data, "Unknown telnet option %s", head->data);
+      return CURLE_UNKNOWN_TELNET_OPTION;
+    } else {
+      failf(data, "Syntax error in telnet option: %s", head->data);
+      return CURLE_TELNET_OPTION_SYNTAX;
+    }
+  }
+
+  return CURLE_OK;
+}
+
+/*
+ * suboption()
+ *
+ * Look at the sub-option buffer, and try to be helpful to the other
+ * side.
+ */
+
+static void suboption(struct connectdata *conn)
+{
+  struct curl_slist *v;
+  unsigned char temp[2048];
+  ssize_t bytes_written;
+  size_t len;
+  size_t tmplen;
+  int err;
+  char varname[128];
+  char varval[128];
+  struct SessionHandle *data = conn->data;
+  struct TELNET *tn = (struct TELNET *)data->state.proto.telnet;
+
+  printsub(data, '<', (unsigned char *)tn->subbuffer, CURL_SB_LEN(tn)+2);
+  switch (CURL_SB_GET(tn)) {
+    case CURL_TELOPT_TTYPE:
+      len = strlen(tn->subopt_ttype) + 4 + 2;
+      snprintf((char *)temp, sizeof(temp),
+               "%c%c%c%c%s%c%c", CURL_IAC, CURL_SB, CURL_TELOPT_TTYPE,
+               CURL_TELQUAL_IS, tn->subopt_ttype, CURL_IAC, CURL_SE);
+      bytes_written = swrite(conn->sock[FIRSTSOCKET], temp, len);
+      if(bytes_written < 0) {
+        err = SOCKERRNO;
+        failf(data,"Sending data failed (%d)",err);
+      }
+      printsub(data, '>', &temp[2], len-2);
+      break;
+    case CURL_TELOPT_XDISPLOC:
+      len = strlen(tn->subopt_xdisploc) + 4 + 2;
+      snprintf((char *)temp, sizeof(temp),
+               "%c%c%c%c%s%c%c", CURL_IAC, CURL_SB, CURL_TELOPT_XDISPLOC,
+               CURL_TELQUAL_IS, tn->subopt_xdisploc, CURL_IAC, CURL_SE);
+      bytes_written = swrite(conn->sock[FIRSTSOCKET], temp, len);
+      if(bytes_written < 0) {
+        err = SOCKERRNO;
+        failf(data,"Sending data failed (%d)",err);
+      }
+      printsub(data, '>', &temp[2], len-2);
+      break;
+    case CURL_TELOPT_NEW_ENVIRON:
+      snprintf((char *)temp, sizeof(temp),
+               "%c%c%c%c", CURL_IAC, CURL_SB, CURL_TELOPT_NEW_ENVIRON,
+               CURL_TELQUAL_IS);
+      len = 4;
+
+      for(v = tn->telnet_vars;v;v = v->next) {
+        tmplen = (strlen(v->data) + 1);
+        /* Add the variable only if it fits */
+        if(len + tmplen < (int)sizeof(temp)-6) {
+          sscanf(v->data, "%127[^,],%127s", varname, varval);
+          snprintf((char *)&temp[len], sizeof(temp) - len,
+                   "%c%s%c%s", CURL_NEW_ENV_VAR, varname,
+                   CURL_NEW_ENV_VALUE, varval);
+          len += tmplen;
+        }
+      }
+      snprintf((char *)&temp[len], sizeof(temp) - len,
+               "%c%c", CURL_IAC, CURL_SE);
+      len += 2;
+      bytes_written = swrite(conn->sock[FIRSTSOCKET], temp, len);
+      if(bytes_written < 0) {
+        err = SOCKERRNO;
+        failf(data,"Sending data failed (%d)",err);
+      }
+      printsub(data, '>', &temp[2], len-2);
+      break;
+  }
+  return;
+}
+
+static
+CURLcode telrcv(struct connectdata *conn,
+                const unsigned char *inbuf, /* Data received from socket */
+                ssize_t count)              /* Number of bytes received */
+{
+  unsigned char c;
+  CURLcode result;
+  int in = 0;
+  int startwrite=-1;
+  struct SessionHandle *data = conn->data;
+  struct TELNET *tn = (struct TELNET *)data->state.proto.telnet;
+
+#define startskipping() \
+    if(startwrite >= 0) { \
+       result = Curl_client_write(conn, \
+                                  CLIENTWRITE_BODY, \
+                                  (char *)&inbuf[startwrite], \
+                                  in-startwrite); \
+      if(result != CURLE_OK) \
+        return result; \
+    } \
+    startwrite = -1
+
+#define writebyte() \
+    if(startwrite < 0) \
+      startwrite = in
+
+#define bufferflush() startskipping()
+
+  while(count--)
+  {
+    c = inbuf[in];
+
+    /*infof(data,"In rcv state %d char %d\n", tn->telrcv_state, c);*/
+    switch (tn->telrcv_state)
+    {
+      case CURL_TS_CR:
+        tn->telrcv_state = CURL_TS_DATA;
+        if(c == '\0')
+        {
+          startskipping();
+          break;   /* Ignore \0 after CR */
+        }
+        writebyte();
+        break;
+
+      case CURL_TS_DATA:
+        if(c == CURL_IAC)
+        {
+          tn->telrcv_state = CURL_TS_IAC;
+          startskipping();
+          break;
+        }
+        else if(c == '\r')
+        {
+          tn->telrcv_state = CURL_TS_CR;
+        }
+        writebyte();
+        break;
+
+      case CURL_TS_IAC:
+      process_iac:
+      DEBUGASSERT(startwrite < 0);
+      switch (c)
+      {
+        case CURL_WILL:
+          tn->telrcv_state = CURL_TS_WILL;
+          break;
+        case CURL_WONT:
+          tn->telrcv_state = CURL_TS_WONT;
+          break;
+        case CURL_DO:
+          tn->telrcv_state = CURL_TS_DO;
+          break;
+        case CURL_DONT:
+          tn->telrcv_state = CURL_TS_DONT;
+          break;
+        case CURL_SB:
+          CURL_SB_CLEAR(tn);
+          tn->telrcv_state = CURL_TS_SB;
+          break;
+        case CURL_IAC:
+          tn->telrcv_state = CURL_TS_DATA;
+          writebyte();
+          break;
+        case CURL_DM:
+        case CURL_NOP:
+        case CURL_GA:
+        default:
+          tn->telrcv_state = CURL_TS_DATA;
+          printoption(data, "RCVD", CURL_IAC, c);
+          break;
+      }
+      break;
+
+      case CURL_TS_WILL:
+        printoption(data, "RCVD", CURL_WILL, c);
+        tn->please_negotiate = 1;
+        rec_will(conn, c);
+        tn->telrcv_state = CURL_TS_DATA;
+        break;
+
+      case CURL_TS_WONT:
+        printoption(data, "RCVD", CURL_WONT, c);
+        tn->please_negotiate = 1;
+        rec_wont(conn, c);
+        tn->telrcv_state = CURL_TS_DATA;
+        break;
+
+      case CURL_TS_DO:
+        printoption(data, "RCVD", CURL_DO, c);
+        tn->please_negotiate = 1;
+        rec_do(conn, c);
+        tn->telrcv_state = CURL_TS_DATA;
+        break;
+
+      case CURL_TS_DONT:
+        printoption(data, "RCVD", CURL_DONT, c);
+        tn->please_negotiate = 1;
+        rec_dont(conn, c);
+        tn->telrcv_state = CURL_TS_DATA;
+        break;
+
+      case CURL_TS_SB:
+        if(c == CURL_IAC)
+        {
+          tn->telrcv_state = CURL_TS_SE;
+        }
+        else
+        {
+          CURL_SB_ACCUM(tn,c);
+        }
+        break;
+
+      case CURL_TS_SE:
+        if(c != CURL_SE)
+        {
+          if(c != CURL_IAC)
+          {
+            /*
+             * This is an error.  We only expect to get "IAC IAC" or "IAC SE".
+             * Several things may have happend.  An IAC was not doubled, the
+             * IAC SE was left off, or another option got inserted into the
+             * suboption are all possibilities.  If we assume that the IAC was
+             * not doubled, and really the IAC SE was left off, we could get
+             * into an infinate loop here.  So, instead, we terminate the
+             * suboption, and process the partial suboption if we can.
+             */
+            CURL_SB_ACCUM(tn, CURL_IAC);
+            CURL_SB_ACCUM(tn, c);
+            tn->subpointer -= 2;
+            CURL_SB_TERM(tn);
+
+            printoption(data, "In SUBOPTION processing, RCVD", CURL_IAC, c);
+            suboption(conn);   /* handle sub-option */
+            tn->telrcv_state = CURL_TS_IAC;
+            goto process_iac;
+          }
+          CURL_SB_ACCUM(tn,c);
+          tn->telrcv_state = CURL_TS_SB;
+        }
+        else
+        {
+          CURL_SB_ACCUM(tn, CURL_IAC);
+          CURL_SB_ACCUM(tn, CURL_SE);
+          tn->subpointer -= 2;
+          CURL_SB_TERM(tn);
+          suboption(conn);   /* handle sub-option */
+          tn->telrcv_state = CURL_TS_DATA;
+        }
+        break;
+    }
+    ++in;
+  }
+  bufferflush();
+  return CURLE_OK;
+}
+
+/* Escape and send a telnet data block */
+/* TODO: write large chunks of data instead of one byte at a time */
+static CURLcode send_telnet_data(struct connectdata *conn,
+                                 char *buffer, ssize_t nread)
+{
+  unsigned char outbuf[2];
+  ssize_t bytes_written, total_written;
+  int out_count;
+  CURLcode rc = CURLE_OK;
+
+  while(rc == CURLE_OK && nread--) {
+    outbuf[0] = *buffer++;
+    out_count = 1;
+    if(outbuf[0] == CURL_IAC)
+      outbuf[out_count++] = CURL_IAC;
+
+    total_written = 0;
+    do {
+      /* Make sure socket is writable to avoid EWOULDBLOCK condition */
+      struct pollfd pfd[1];
+      pfd[0].fd = conn->sock[FIRSTSOCKET];
+      pfd[0].events = POLLOUT;
+      switch (Curl_poll(pfd, 1, -1)) {
+        case -1:                    /* error, abort writing */
+        case 0:                     /* timeout (will never happen) */
+          rc = CURLE_SEND_ERROR;
+          break;
+        default:                    /* write! */
+          bytes_written = 0;
+          rc = Curl_write(conn, conn->sock[FIRSTSOCKET], outbuf+total_written,
+                          out_count-total_written, &bytes_written);
+          total_written += bytes_written;
+          break;
+      }
+    /* handle partial write */
+    } while (rc == CURLE_OK && total_written < out_count);
+  }
+  return rc;
+}
+
+static CURLcode telnet_done(struct connectdata *conn,
+                                 CURLcode status, bool premature)
+{
+  struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet;
+  (void)status; /* unused */
+  (void)premature; /* not used */
+
+  curl_slist_free_all(tn->telnet_vars);
+
+  free(conn->data->state.proto.telnet);
+  conn->data->state.proto.telnet = NULL;
+
+  return CURLE_OK;
+}
+
+static CURLcode telnet_do(struct connectdata *conn, bool *done)
+{
+  CURLcode code;
+  struct SessionHandle *data = conn->data;
+  curl_socket_t sockfd = conn->sock[FIRSTSOCKET];
+#ifdef USE_WINSOCK
+  HMODULE wsock2;
+  WSOCK2_FUNC close_event_func;
+  WSOCK2_FUNC create_event_func;
+  WSOCK2_FUNC event_select_func;
+  WSOCK2_FUNC enum_netevents_func;
+  WSAEVENT event_handle;
+  WSANETWORKEVENTS events;
+  HANDLE stdin_handle;
+  HANDLE objs[2];
+  DWORD  obj_count;
+  DWORD  wait_timeout;
+  DWORD waitret;
+  DWORD readfile_read;
+  int err;
+#else
+  int interval_ms;
+  struct pollfd pfd[2];
+#endif
+  int ret;
+  ssize_t nread;
+  struct timeval now;
+  bool keepon = TRUE;
+  char *buf = data->state.buffer;
+  struct TELNET *tn;
+
+  *done = TRUE; /* unconditionally */
+
+  code = init_telnet(conn);
+  if(code)
+    return code;
+
+  tn = (struct TELNET *)data->state.proto.telnet;
+
+  code = check_telnet_options(conn);
+  if(code)
+    return code;
+
+#ifdef USE_WINSOCK
+  /*
+  ** This functionality only works with WinSock >= 2.0.  So,
+  ** make sure have it.
+  */
+  code = check_wsock2(data);
+  if(code)
+    return code;
+
+  /* OK, so we have WinSock 2.0.  We need to dynamically */
+  /* load ws2_32.dll and get the function pointers we need. */
+  wsock2 = LoadLibrary("WS2_32.DLL");
+  if(wsock2 == NULL) {
+    failf(data,"failed to load WS2_32.DLL (%d)", ERRNO);
+    return CURLE_FAILED_INIT;
+  }
+
+  /* Grab a pointer to WSACreateEvent */
+  create_event_func = GetProcAddress(wsock2,"WSACreateEvent");
+  if(create_event_func == NULL) {
+    failf(data,"failed to find WSACreateEvent function (%d)",
+          ERRNO);
+    FreeLibrary(wsock2);
+    return CURLE_FAILED_INIT;
+  }
+
+  /* And WSACloseEvent */
+  close_event_func = GetProcAddress(wsock2,"WSACloseEvent");
+  if(close_event_func == NULL) {
+    failf(data,"failed to find WSACloseEvent function (%d)",
+          ERRNO);
+    FreeLibrary(wsock2);
+    return CURLE_FAILED_INIT;
+  }
+
+  /* And WSAEventSelect */
+  event_select_func = GetProcAddress(wsock2,"WSAEventSelect");
+  if(event_select_func == NULL) {
+    failf(data,"failed to find WSAEventSelect function (%d)",
+          ERRNO);
+    FreeLibrary(wsock2);
+    return CURLE_FAILED_INIT;
+  }
+
+  /* And WSAEnumNetworkEvents */
+  enum_netevents_func = GetProcAddress(wsock2,"WSAEnumNetworkEvents");
+  if(enum_netevents_func == NULL) {
+    failf(data,"failed to find WSAEnumNetworkEvents function (%d)",
+          ERRNO);
+    FreeLibrary(wsock2);
+    return CURLE_FAILED_INIT;
+  }
+
+  /* We want to wait for both stdin and the socket. Since
+  ** the select() function in winsock only works on sockets
+  ** we have to use the WaitForMultipleObjects() call.
+  */
+
+  /* First, create a sockets event object */
+  event_handle = (WSAEVENT)create_event_func();
+  if(event_handle == WSA_INVALID_EVENT) {
+    failf(data,"WSACreateEvent failed (%d)", SOCKERRNO);
+    FreeLibrary(wsock2);
+    return CURLE_FAILED_INIT;
+  }
+
+  /* The get the Windows file handle for stdin */
+  stdin_handle = GetStdHandle(STD_INPUT_HANDLE);
+
+  /* Create the list of objects to wait for */
+  objs[0] = event_handle;
+  objs[1] = stdin_handle;
+
+  /* Tell winsock what events we want to listen to */
+  if(event_select_func(sockfd, event_handle, FD_READ|FD_CLOSE) == SOCKET_ERROR) {
+    close_event_func(event_handle);
+    FreeLibrary(wsock2);
+    return CURLE_OK;
+  }
+
+  /* If stdin_handle is a pipe, use PeekNamedPipe() method to check it,
+     else use the old WaitForMultipleObjects() way */
+  if(GetFileType(stdin_handle) == FILE_TYPE_PIPE) {
+    /* Don't wait for stdin_handle, just wait for event_handle */
+    obj_count = 1;
+    /* Check stdin_handle per 100 milliseconds */
+    wait_timeout = 100;
+  } else {
+    obj_count = 2;
+    wait_timeout = 1000;
+  }
+
+  /* Keep on listening and act on events */
+  while(keepon) {
+    waitret = WaitForMultipleObjects(obj_count, objs, FALSE, wait_timeout);
+    switch(waitret) {
+    case WAIT_TIMEOUT:
+    {
+      for(;;) {
+        if(!PeekNamedPipe(stdin_handle, NULL, 0, NULL, &readfile_read, NULL)) {
+          keepon = FALSE;
+          code = CURLE_READ_ERROR;
+          break;
+        }
+
+        if(!readfile_read)
+          break;
+
+        if(!ReadFile(stdin_handle, buf, sizeof(data->state.buffer),
+                     &readfile_read, NULL)) {
+          keepon = FALSE;
+          code = CURLE_READ_ERROR;
+          break;
+        }
+
+        code = send_telnet_data(conn, buf, readfile_read);
+        if(code) {
+          keepon = FALSE;
+          break;
+        }
+      }
+    }
+    break;
+
+    case WAIT_OBJECT_0 + 1:
+    {
+      if(!ReadFile(stdin_handle, buf, sizeof(data->state.buffer),
+                   &readfile_read, NULL)) {
+        keepon = FALSE;
+        code = CURLE_READ_ERROR;
+        break;
+      }
+
+      code = send_telnet_data(conn, buf, readfile_read);
+      if(code) {
+        keepon = FALSE;
+        break;
+      }
+    }
+    break;
+
+    case WAIT_OBJECT_0:
+
+      if(SOCKET_ERROR == enum_netevents_func(sockfd, event_handle, &events)) {
+        if((err = SOCKERRNO) != EINPROGRESS) {
+          infof(data,"WSAEnumNetworkEvents failed (%d)", err);
+          keepon = FALSE;
+          code = CURLE_READ_ERROR;
+        }
+        break;
+      }
+      if(events.lNetworkEvents & FD_READ) {
+        /* read data from network */
+        ret = Curl_read(conn, sockfd, buf, BUFSIZE - 1, &nread);
+        /* returned sub-zero, this would've blocked. Loop again */
+        if(ret < 0)
+          break;
+        /* returned not-zero, this an error */
+        else if(ret) {
+          keepon = FALSE;
+          code = (CURLcode)ret;
+          break;
+        }
+        /* returned zero but actually received 0 or less here,
+           the server closed the connection and we bail out */
+        else if(nread <= 0) {
+          keepon = FALSE;
+          break;
+        }
+
+        code = telrcv(conn, (unsigned char *)buf, nread);
+        if(code) {
+          keepon = FALSE;
+          break;
+        }
+
+        fflush(stdout);
+
+        /* Negotiate if the peer has started negotiating,
+           otherwise don't. We don't want to speak telnet with
+           non-telnet servers, like POP or SMTP. */
+        if(tn->please_negotiate && !tn->already_negotiated) {
+          negotiate(conn);
+          tn->already_negotiated = 1;
+        }
+      }
+      if(events.lNetworkEvents & FD_CLOSE) {
+        keepon = FALSE;
+      }
+      break;
+
+    }
+
+    if(data->set.timeout) {
+      now = Curl_tvnow();
+      if(Curl_tvdiff(now, conn->created) >= data->set.timeout) {
+        failf(data, "Time-out");
+        code = CURLE_OPERATION_TIMEDOUT;
+        keepon = FALSE;
+      }
+    }
+  }
+
+  /* We called WSACreateEvent, so call WSACloseEvent */
+  if(close_event_func(event_handle) == FALSE) {
+    infof(data,"WSACloseEvent failed (%d)", SOCKERRNO);
+  }
+
+  /* "Forget" pointers into the library we're about to free */
+  create_event_func = NULL;
+  close_event_func = NULL;
+  event_select_func = NULL;
+  enum_netevents_func = NULL;
+
+  /* We called LoadLibrary, so call FreeLibrary */
+  if(!FreeLibrary(wsock2))
+    infof(data,"FreeLibrary(wsock2) failed (%d)", ERRNO);
+#else
+  pfd[0].fd = sockfd;
+  pfd[0].events = POLLIN;
+  pfd[1].fd = 0;
+  pfd[1].events = POLLIN;
+  interval_ms = 1 * 1000;
+
+  while(keepon) {
+    switch (Curl_poll(pfd, 2, interval_ms)) {
+    case -1:                    /* error, stop reading */
+      keepon = FALSE;
+      continue;
+    case 0:                     /* timeout */
+      break;
+    default:                    /* read! */
+      if(pfd[1].revents & POLLIN) { /* read from stdin */
+        nread = read(0, buf, 255);
+        code = send_telnet_data(conn, buf, nread);
+        if(code) {
+          keepon = FALSE;
+          break;
+        }
+      }
+
+      if(pfd[0].revents & POLLIN) {
+        /* read data from network */
+        ret = Curl_read(conn, sockfd, buf, BUFSIZE - 1, &nread);
+        /* returned sub-zero, this would've blocked. Loop again */
+        if(ret < 0)
+          break;
+        /* returned not-zero, this an error */
+        else if(ret) {
+          keepon = FALSE;
+          code = (CURLcode)ret;
+          break;
+        }
+        /* returned zero but actually received 0 or less here,
+           the server closed the connection and we bail out */
+        else if(nread <= 0) {
+          keepon = FALSE;
+          break;
+        }
+
+        code = telrcv(conn, (unsigned char *)buf, nread);
+        if(code) {
+          keepon = FALSE;
+          break;
+        }
+
+        /* Negotiate if the peer has started negotiating,
+           otherwise don't. We don't want to speak telnet with
+           non-telnet servers, like POP or SMTP. */
+        if(tn->please_negotiate && !tn->already_negotiated) {
+          negotiate(conn);
+          tn->already_negotiated = 1;
+        }
+      }
+    }
+    if(data->set.timeout) {
+      now = Curl_tvnow();
+      if(Curl_tvdiff(now, conn->created) >= data->set.timeout) {
+        failf(data, "Time-out");
+        code = CURLE_OPERATION_TIMEDOUT;
+        keepon = FALSE;
+      }
+    }
+  }
+#endif
+  /* mark this as "no further transfer wanted" */
+  Curl_setup_transfer(conn, -1, -1, FALSE, NULL, -1, NULL);
+
+  return code;
+}
+#endif