src/unix/dialup.cpp

   1 // -*- c++ -*- ///////////////////////////////////////////////////////////////
   2 // Name:        unix/dialup.cpp
   3 // Purpose:     Network related wxWindows classes and functions
   4 // Author:      Karsten Ballüder
   5 // Modified by:
   6 // Created:     03.10.99
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Karsten Ballüder
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #include "wx/setup.h"
  13
  14 #if wxUSE_DIALUP_MANAGER
  15
  16 #ifndef  WX_PRECOMP
  17 #   include "wx/defs.h"
  18 #endif // !PCH
  19
  20 #include "wx/string.h"
  21 #include "wx/event.h"
  22 #include "wx/net.h"
  23 #include "wx/timer.h"
  24 #include "wx/filefn.h"
  25 #include "wx/utils.h"
  26 #include "wx/log.h"
  27
  28 #include <stdlib.h>
  29
  30 #include <signal.h>
  31 #include <fcntl.h>
  32 #include <unistd.h>
  33 #define __STRICT_ANSI__
  34 #include <sys/socket.h>
  35 #include <netdb.h>
  36 #include <netinet/in.h>
  37 #include <arpa/inet.h>
  38
  39 // ----------------------------------------------------------------------------
  40 // A class which groups functions dealing with connecting to the network from a
  41 // workstation using dial-up access to the net. There is at most one instance
  42 // of this class in the program accessed via GetDialUpManager().
  43 // ----------------------------------------------------------------------------
  44
  45 /* TODO
  46  *
  47  * 1. more configurability for Unix: i.e. how to initiate the connection, how
  48  *    to check for online status, &c.
  49  * 2. add a "long Dial(long connectionId = -1)" function which asks the user
  50  *    about which connection to dial (this may be done using native dialogs
  51  *    under NT, need generic dialogs for all others) and returns the identifier
  52  *    of the selected connection (it's opaque to the application) - it may be
  53  *    reused later to dial the same connection later (or use strings instead of
  54  *    longs may be?)
  55  * 3. add an async version of dialing functions which notify the caller about
  56  *    the progress (or may be even start another thread to monitor it)
  57  * 4. the static creation/accessor functions are not MT-safe - but is this
  58  *    really crucial? I think we may suppose they're always called from the
  59  *    main thread?
  60  */
  61
  62 class WXDLLEXPORT wxDialUpManagerImpl : public wxDialUpManager
  63 {
  64 public:
  65    wxDialUpManagerImpl()
  66       {
  67          m_IsOnline = -1; // unknown
  68          m_timer = NULL;
  69          m_CanUseIfconfig = -1; // unknown
  70          m_BeaconHost = WXDIALUP_MANAGER_DEFAULT_BEACONHOST;
  71          m_BeaconPort = 80;
  72       }
  73
  74    /** Could the dialup manager be initialized correctly? If this function
  75        returns FALSE, no other functions will work neither, so it's a good idea
  76        to call this function and check its result before calling any other
  77        wxDialUpManager methods.
  78    */
  79    virtual bool IsOk() const
  80       { return TRUE; }
  81
  82    /** The simplest way to initiate a dial up: this function dials the given
  83        ISP (exact meaning of the parameter depends on the platform), returns
  84        TRUE on success or FALSE on failure and logs the appropriate error
  85        message in the latter case.
  86        @param nameOfISP optional paramater for dial program
  87        @param username unused
  88        @param password unused
  89    */
  90    virtual bool Dial(const wxString& nameOfISP,
  91                      const wxString& WXUNUSED(username),
  92                      const wxString& WXUNUSED(password),
  93                      bool async);
  94
  95    /// Hang up the currently active dial up connection.
  96    virtual bool HangUp();
  97
  98    // returns TRUE if the computer is connected to the network: under Windows,
  99    // this just means that a RAS connection exists, under Unix we check that
 100    // the "well-known host" (as specified by SetWellKnownHost) is reachable
 101    virtual bool IsOnline() const
 102       {
 103          if( (! m_timer) // we are not polling, so test now:
 104              || m_IsOnline == -1
 105             )
 106             CheckStatus();
 107          return m_IsOnline != 0;
 108       }
 109
 110    // sometimes the built-in logic for determining the online status may fail,
 111    // so, in general, the user should be allowed to override it. This function
 112    // allows to forcefully set the online status - whatever our internal
 113    // algorithm may think about it.
 114    virtual void SetOnlineStatus(bool isOnline = TRUE)
 115       { m_IsOnline = isOnline; }
 116
 117    // set misc wxDialUpManager options
 118    // --------------------------------
 119
 120    // enable automatical checks for the connection status and sending of
 121    // wxEVT_DIALUP_CONNECTED/wxEVT_DIALUP_DISCONNECTED events. The interval
 122    // parameter is only for Unix where we do the check manually: under
 123    // Windows, the notification about the change of connection status is
 124    // instantenous.
 125    //
 126    // Returns FALSE if couldn't set up automatic check for online status.
 127    virtual bool EnableAutoCheckOnlineStatus(size_t nSeconds);
 128
 129    // disable automatic check for connection status change - notice that the
 130    // wxEVT_DIALUP_XXX events won't be sent any more neither.
 131    virtual void DisableAutoCheckOnlineStatus();
 132
 133    // under Unix, the value of well-known host is used to check whether we're
 134    // connected to the internet. It's unused under Windows, but this function
 135    // is always safe to call. The default value is www.yahoo.com.
 136    virtual void SetWellKnownHost(const wxString& hostname,
 137                                  int portno = 80);
 138    /** Sets the commands to start up the network and to hang up
 139        again. Used by the Unix implementations only.
 140    */
 141    virtual void SetConnectCommand(const wxString &command, const wxString &hupcmd)
 142       { m_ConnectCommand = command; m_HangUpCommand = hupcmd; }
 143
 144 private:
 145    /// -1: don´t know, 0 = no, 1 = yes
 146    int m_IsOnline;
 147
 148    ///  Can we use ifconfig to list active devices?
 149    int m_CanUseIfconfig;
 150    /// The path to ifconfig
 151    wxString m_IfconfigPath;
 152
 153    /// beacon host:
 154    wxString m_BeaconHost;
 155    /// beacon host portnumber for connect:
 156    int m_BeaconPort;
 157
 158    /// command to connect to network
 159    wxString m_ConnectCommand;
 160    /// command to hang up
 161    wxString m_HangUpCommand;
 162    /// name of ISP
 163    wxString m_ISPname;
 164    /// a timer for regular testing
 165    class AutoCheckTimer *m_timer;
 166
 167    friend class AutoCheckTimer;
 168    /// determine status
 169    void CheckStatus(void) const;
 170
 171    /// real status check
 172    void CheckStatusInternal(void);
 173 };
 174
 175
 176 class AutoCheckTimer : public wxTimer
 177 {
 178 public:
 179    AutoCheckTimer(wxDialUpManagerImpl *dupman)
 180       {
 181          m_dupman = dupman;
 182          m_started = FALSE;
 183       }
 184
 185    virtual bool Start( int millisecs = -1 )
 186       { m_started = TRUE; return wxTimer::Start(millisecs, FALSE); }
 187
 188    virtual void Notify()
 189       { wxLogTrace("Checking dial up network status."); m_dupman->CheckStatus(); }
 190
 191    virtual void Stop()
 192       { if ( m_started ) wxTimer::Stop(); }
 193 public:
 194    bool m_started;
 195    wxDialUpManagerImpl *m_dupman;
 196 };
 197
 198 bool
 199 wxDialUpManagerImpl::Dial(const wxString &isp,
 200                           const wxString & WXUNUSED(username),
 201                           const wxString & WXUNUSED(password),
 202                           bool async)
 203 {
 204    if(m_IsOnline == 1)
 205       return FALSE;
 206    m_IsOnline = -1;
 207    m_ISPname = isp;
 208    wxString cmd;
 209    if(m_ConnectCommand.Find("%s"))
 210       cmd.Printf(m_ConnectCommand,m_ISPname.c_str());
 211    else
 212       cmd = m_ConnectCommand;
 213
 214    if ( async )
 215    {
 216        wxFAIL_MSG(_T("TODO"));
 217    }
 218    else
 219    {
 220        return wxExecute(cmd, /* sync */ TRUE) == 0;
 221    }
 222 }
 223
 224 bool
 225 wxDialUpManagerImpl::HangUp(void)
 226 {
 227    if(m_IsOnline == 0)
 228       return FALSE;
 229    m_IsOnline = -1;
 230    wxString cmd;
 231    if(m_HangUpCommand.Find("%s"))
 232       cmd.Printf(m_HangUpCommand,m_ISPname.c_str());
 233    else
 234       cmd = m_HangUpCommand;
 235    return wxExecute(cmd, /* sync */ TRUE) == 0;
 236 }
 237
 238
 239 bool
 240 wxDialUpManagerImpl::EnableAutoCheckOnlineStatus(size_t nSeconds)
 241 {
 242    wxASSERT(m_timer == NULL);
 243    m_timer = new AutoCheckTimer(this);
 244    bool rc = m_timer->Start(nSeconds*1000);
 245    if(! rc)
 246    {
 247       delete m_timer;
 248       m_timer = NULL;
 249    }
 250    return rc;
 251 }
 252
 253 void
 254 wxDialUpManagerImpl::DisableAutoCheckOnlineStatus()
 255 {
 256    wxASSERT(m_timer != NULL);
 257    m_timer->Stop();
 258    delete m_timer;
 259    m_timer = NULL;
 260 }
 261
 262
 263 void
 264 wxDialUpManagerImpl::SetWellKnownHost(const wxString& hostname, int portno)
 265 {
 266    /// does hostname contain a port number?
 267    wxString port = hostname.After(':');
 268    if(port.Length())
 269    {
 270       m_BeaconHost = hostname.Before(':');
 271       m_BeaconPort = atoi(port);
 272    }
 273    else
 274    {
 275       m_BeaconHost = hostname;
 276       m_BeaconPort = portno;
 277    }
 278 }
 279
 280
 281 void
 282 wxDialUpManagerImpl::CheckStatus(void) const
 283 {
 284    // This function calls the CheckStatusInternal() helper function
 285    // which is OS - specific and then sends the events.
 286
 287    int oldIsOnline = m_IsOnline;
 288    ( /* non-const */ (wxDialUpManagerImpl *)this)->CheckStatusInternal();
 289
 290    // now send the events as appropriate:
 291    if(m_IsOnline != oldIsOnline)
 292    {
 293       if(m_IsOnline)
 294          ; // send ev
 295       else
 296          ; // send ev
 297    }
 298 }
 299
 300 /*
 301   We have three methods that we can use:
 302
 303   1. test via /sbin/ifconfig and grep for "sl", "ppp", "pl"
 304      --> should be fast enough for regular polling
 305   2. test if we can reach the well known beacon host
 306      --> too slow for polling
 307   3. check /proc/net/dev on linux??
 308      This method should be preferred, if possible. Need to do more
 309      testing.
 310
 311 */
 312
 313 void
 314 wxDialUpManagerImpl::CheckStatusInternal(void)
 315 {
 316    m_IsOnline = -1;
 317
 318    // First time check for ifconfig location. We only use the variant
 319    // which does not take arguments, a la GNU.
 320    if(m_CanUseIfconfig == -1) // unknown
 321    {
 322       if(wxFileExists("/sbin/ifconfig"))
 323          m_IfconfigPath = "/sbin/ifconfig";
 324       else if(wxFileExists("/usr/sbin/ifconfig"))
 325          m_IfconfigPath = "/usr/sbin/ifconfig";
 326    }
 327
 328    wxLogNull ln; // suppress all error messages
 329    // Let´s try the ifconfig method first, should be fastest:
 330    if(m_CanUseIfconfig != 0) // unknown or yes
 331    {
 332       wxASSERT(m_IfconfigPath.length());
 333
 334       wxString tmpfile = wxGetTempFileName("_wxdialuptest");
 335       wxString cmd = "/bin/sh -c \'";
 336       cmd << m_IfconfigPath << " >" << tmpfile <<  '\'';
 337       /* I tried to add an option to wxExecute() to not close stdout,
 338          so we could let ifconfig write directly to the tmpfile, but
 339          this does not work. That should be faster, as it doesn´t call
 340          the shell first. I have no idea why. :-(  (KB) */
 341 #if 0
 342       // temporarily redirect stdout/stderr:
 343       int
 344          new_stdout = dup(STDOUT_FILENO),
 345          new_stderr = dup(STDERR_FILENO);
 346       close(STDOUT_FILENO);
 347       close(STDERR_FILENO);
 348
 349       int
 350          // new stdout:
 351          output_fd = open(tmpfile, O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR),
 352          // new stderr:
 353          null_fd = open("/dev/null", O_CREAT, S_IRUSR|S_IWUSR);
 354       // verify well behaved unix behaviour:
 355       wxASSERT(output_fd == STDOUT_FILENO);
 356       wxASSERT(null_fd == STDERR_FILENO);
 357       int rc = wxExecute(m_IfconfigPath,TRUE /* sync */,NULL ,wxEXECUTE_DONT_CLOSE_FDS);
 358       close(null_fd); close(output_fd);
 359       // restore old stdout, stderr:
 360       int test;
 361       test = dup(new_stdout); close(new_stdout); wxASSERT(test == STDOUT_FILENO);
 362       test = dup(new_stderr); close(new_stderr); wxASSERT(test == STDERR_FILENO);
 363       if(rc == 0)
 364 #endif
 365       if(wxExecute(cmd,TRUE /* sync */) == 0)
 366       {
 367          m_CanUseIfconfig = 1;
 368          wxFile file;
 369          if( file.Open(tmpfile) )
 370          {
 371             char *output = new char [file.Length()+1];
 372             output[file.Length()] = '\0';
 373             if(file.Read(output,file.Length()) == file.Length())
 374             {
 375                if(strstr(output,"ppp")   // ppp
 376                   || strstr(output,"sl") // slip
 377                   || strstr(output,"pl") // plip
 378                   )
 379                   m_IsOnline = 1;
 380                else
 381                   m_IsOnline = 0;
 382             }
 383             file.Close();
 384             delete [] output;
 385          }
 386          // else m_IsOnline remains -1 as we don't know for sure
 387       }
 388       else // could not run ifconfig correctly
 389          m_CanUseIfconfig = 0; // don´t try again
 390       (void) wxRemoveFile(tmpfile);
 391       if(m_IsOnline != -1) // we are done
 392          return;
 393    }
 394
 395    // second method: try to connect to well known host:
 396    // This can be used under Win 9x, too!
 397    struct hostent     *hp;
 398    struct sockaddr_in  serv_addr;
 399    int  sockfd;
 400
 401    m_IsOnline = 0; // assume false
 402    if((hp = gethostbyname(m_BeaconHost)) == NULL)
 403       return; // no DNS no net
 404
 405    serv_addr.sin_family         = hp->h_addrtype;
 406    memcpy(&serv_addr.sin_addr,hp->h_addr, hp->h_length);
 407    serv_addr.sin_port           = htons(m_BeaconPort);
 408    if( ( sockfd = socket(hp->h_addrtype, SOCK_STREAM, 0)) < 0)
 409    {
 410       //  sys_error("cannot create socket for gw");
 411       return;
 412    }
 413    if( connect(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
 414    {
 415       //sys_error("cannot connect to server");
 416       return;
 417    }
 418    //connected!
 419    close(sockfd);
 420 }
 421
 422
 423 /* static */
 424 wxDialUpManager *
 425 wxDialUpManager::wxDialUpManager::Create(void)
 426 {
 427    return new wxDialUpManagerImpl;
 428 }
 429
 430 #endif // wxUSE_DIALUP_MANAGER