src/unix/utilsunx.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        utilsunx.cpp
   3 // Purpose:     generic Unix implementation of many wx functions
   4 // Author:      Vadim Zeitlin
   5 // Id:          $Id$
   6 // Copyright:   (c) 1998 Robert Roebling, Vadim Zeitlin
   7 // Licence:     wxWindows licence
   8 /////////////////////////////////////////////////////////////////////////////
   9
  10 // ============================================================================
  11 // declarations
  12 // ============================================================================
  13
  14 // ----------------------------------------------------------------------------
  15 // headers
  16 // ----------------------------------------------------------------------------
  17
  18 #include "wx/defs.h"
  19 #include "wx/string.h"
  20
  21 #include "wx/intl.h"
  22 #include "wx/log.h"
  23 #include "wx/app.h"
  24
  25 #include "wx/utils.h"
  26 #include "wx/process.h"
  27 #include "wx/thread.h"
  28
  29 #include "wx/stream.h"
  30
  31 #ifdef HAVE_STATFS
  32     #include <sys/vfs.h>
  33 #endif // HAVE_STATFS
  34
  35 #if wxUSE_GUI
  36     #include "wx/unix/execute.h"
  37 #endif
  38
  39 // SGI signal.h defines signal handler arguments differently depending on
  40 // whether _LANGUAGE_C_PLUS_PLUS is set or not - do set it
  41 #if defined(__SGI__) && !defined(_LANGUAGE_C_PLUS_PLUS)
  42     #define _LANGUAGE_C_PLUS_PLUS 1
  43 #endif // SGI hack
  44
  45 #include <stdarg.h>
  46 #include <dirent.h>
  47 #include <string.h>
  48 #include <sys/stat.h>
  49 #include <sys/types.h>
  50 #include <unistd.h>
  51 #include <sys/wait.h>
  52 #include <pwd.h>
  53 #include <errno.h>
  54 #include <netdb.h>
  55 #include <signal.h>
  56 #include <fcntl.h>          // for O_WRONLY and friends
  57 #include <time.h>           // nanosleep() and/or usleep()
  58 #include <ctype.h>          // isspace()
  59 #include <sys/time.h>       // needed for FD_SETSIZE
  60
  61 #ifdef HAVE_UNAME
  62     #include <sys/utsname.h> // for uname()
  63 #endif // HAVE_UNAME
  64
  65 // ----------------------------------------------------------------------------
  66 // conditional compilation
  67 // ----------------------------------------------------------------------------
  68
  69 // many versions of Unices have this function, but it is not defined in system
  70 // headers - please add your system here if it is the case for your OS.
  71 // SunOS < 5.6 (i.e. Solaris < 2.6) and DG-UX are like this.
  72 #if !defined(HAVE_USLEEP) && \
  73     (defined(__SUN__) && !defined(__SunOs_5_6) && \
  74                          !defined(__SunOs_5_7) && !defined(__SUNPRO_CC)) || \
  75      defined(__osf__) || defined(__EMX__)
  76     extern "C"
  77     {
  78         #ifdef __SUN__
  79             int usleep(unsigned int usec);
  80         #else // !Sun
  81             #ifdef __EMX__
  82                 /* I copied this from the XFree86 diffs. AV. */
  83                 #define INCL_DOSPROCESS
  84                 #include <os2.h>
  85                 inline void usleep(unsigned long delay)
  86                 {
  87                     DosSleep(delay ? (delay/1000l) : 1l);
  88                 }
  89             #else // !Sun && !EMX
  90                 void usleep(unsigned long usec);
  91             #endif
  92         #endif // Sun/EMX/Something else
  93     };
  94
  95     #define HAVE_USLEEP 1
  96 #endif // Unices without usleep()
  97
  98 // ============================================================================
  99 // implementation
 100 // ============================================================================
 101
 102 // ----------------------------------------------------------------------------
 103 // sleeping
 104 // ----------------------------------------------------------------------------
 105
 106 void wxSleep(int nSecs)
 107 {
 108     sleep(nSecs);
 109 }
 110
 111 void wxUsleep(unsigned long milliseconds)
 112 {
 113 #if defined(HAVE_NANOSLEEP)
 114     timespec tmReq;
 115     tmReq.tv_sec = (time_t)(milliseconds / 1000);
 116     tmReq.tv_nsec = (milliseconds % 1000) * 1000 * 1000;
 117
 118     // we're not interested in remaining time nor in return value
 119     (void)nanosleep(&tmReq, (timespec *)NULL);
 120 #elif defined(HAVE_USLEEP)
 121     // uncomment this if you feel brave or if you are sure that your version
 122     // of Solaris has a safe usleep() function but please notice that usleep()
 123     // is known to lead to crashes in MT programs in Solaris 2.[67] and is not
 124     // documented as MT-Safe
 125     #if defined(__SUN__) && wxUSE_THREADS
 126         #error "usleep() cannot be used in MT programs under Solaris."
 127     #endif // Sun
 128
 129     usleep(milliseconds * 1000); // usleep(3) wants microseconds
 130 #elif defined(HAVE_SLEEP)
 131     // under BeOS sleep() takes seconds (what about other platforms, if any?)
 132     sleep(milliseconds * 1000);
 133 #else // !sleep function
 134     #error "usleep() or nanosleep() function required for wxUsleep"
 135 #endif // sleep function
 136 }
 137
 138 // ----------------------------------------------------------------------------
 139 // process management
 140 // ----------------------------------------------------------------------------
 141
 142 int wxKill(long pid, wxSignal sig, wxKillError *rc)
 143 {
 144     int err = kill((pid_t)pid, (int)sig);
 145     if ( rc )
 146     {
 147         switch ( err )
 148         {
 149             case 0:
 150                 *rc = wxKILL_OK;
 151                 break;
 152
 153             case EINVAL:
 154                 *rc = wxKILL_BAD_SIGNAL;
 155                 break;
 156
 157             case EPERM:
 158                 *rc = wxKILL_ACCESS_DENIED;
 159                 break;
 160
 161             case ESRCH:
 162                 *rc = wxKILL_NO_PROCESS;
 163                 break;
 164
 165             default:
 166                 // this goes against Unix98 docs so log it
 167                 wxLogDebug(_T("unexpected kill(2) return value %d"), err);
 168
 169                 // something else...
 170                 *rc = wxKILL_ERROR;
 171         }
 172     }
 173
 174     return err;
 175 }
 176
 177 #define WXEXECUTE_NARGS   127
 178
 179 long wxExecute( const wxString& command, bool sync, wxProcess *process )
 180 {
 181     wxCHECK_MSG( !command.IsEmpty(), 0, wxT("can't exec empty command") );
 182
 183     int argc = 0;
 184     wxChar *argv[WXEXECUTE_NARGS];
 185     wxString argument;
 186     const wxChar *cptr = command.c_str();
 187     wxChar quotechar = wxT('\0'); // is arg quoted?
 188     bool escaped = FALSE;
 189
 190     // split the command line in arguments
 191     do
 192     {
 193         argument=wxT("");
 194         quotechar = wxT('\0');
 195
 196         // eat leading whitespace:
 197         while ( wxIsspace(*cptr) )
 198             cptr++;
 199
 200         if ( *cptr == wxT('\'') || *cptr == wxT('"') )
 201             quotechar = *cptr++;
 202
 203         do
 204         {
 205             if ( *cptr == wxT('\\') && ! escaped )
 206             {
 207                 escaped = TRUE;
 208                 cptr++;
 209                 continue;
 210             }
 211
 212             // all other characters:
 213             argument += *cptr++;
 214             escaped = FALSE;
 215
 216             // have we reached the end of the argument?
 217             if ( (*cptr == quotechar && ! escaped)
 218                  || (quotechar == wxT('\0') && wxIsspace(*cptr))
 219                  || *cptr == wxT('\0') )
 220             {
 221                 wxASSERT_MSG( argc < WXEXECUTE_NARGS,
 222                               wxT("too many arguments in wxExecute") );
 223
 224                 argv[argc] = new wxChar[argument.length() + 1];
 225                 wxStrcpy(argv[argc], argument.c_str());
 226                 argc++;
 227
 228                 // if not at end of buffer, swallow last character:
 229                 if(*cptr)
 230                     cptr++;
 231
 232                 break; // done with this one, start over
 233             }
 234         } while(*cptr);
 235     } while(*cptr);
 236     argv[argc] = NULL;
 237
 238     // do execute the command
 239     long lRc = wxExecute(argv, sync, process);
 240
 241     // clean up
 242     argc = 0;
 243     while( argv[argc] )
 244         delete [] argv[argc++];
 245
 246     return lRc;
 247 }
 248
 249 // ----------------------------------------------------------------------------
 250 // wxShell
 251 // ----------------------------------------------------------------------------
 252
 253 static wxString wxMakeShellCommand(const wxString& command)
 254 {
 255     wxString cmd;
 256     if ( !command )
 257     {
 258         // just an interactive shell
 259         cmd = _T("xterm");
 260     }
 261     else
 262     {
 263         // execute command in a shell
 264         cmd << _T("/bin/sh -c '") << command << _T('\'');
 265     }
 266
 267     return cmd;
 268 }
 269
 270 bool wxShell(const wxString& command)
 271 {
 272     return wxExecute(wxMakeShellCommand(command), TRUE /* sync */) == 0;
 273 }
 274
 275 bool wxShell(const wxString& command, wxArrayString& output)
 276 {
 277     wxCHECK_MSG( !!command, FALSE, _T("can't exec shell non interactively") );
 278
 279     return wxExecute(wxMakeShellCommand(command), output);
 280 }
 281
 282 #if wxUSE_GUI
 283
 284 void wxHandleProcessTermination(wxEndProcessData *proc_data)
 285 {
 286     int pid = (proc_data->pid > 0) ? proc_data->pid : -(proc_data->pid);
 287
 288     // waitpid is POSIX so should be available everywhere, however on older
 289     // systems wait() might be used instead in a loop (until the right pid
 290     // terminates)
 291     int status = 0;
 292     int rc;
 293
 294     // wait for child termination and if waitpid() was interrupted, try again
 295     do
 296     {
 297        rc = waitpid(pid, &status, 0);
 298     }
 299     while ( rc == -1 && errno == EINTR );
 300
 301
 302     if( rc == -1 || ! (WIFEXITED(status) || WIFSIGNALED(status)) )
 303     {
 304        // wxLogSysError(_("Waiting for subprocess termination failed"));
 305        /* AFAIK, this can only happen if something went wrong within
 306           wxGTK, i.e. due to a race condition or some serious bug.
 307           After having fixed the order of statements in
 308           GTK_EndProcessDetector(). (KB)
 309
 310           JACS adds -- I have other code that kills a process recursively
 311           and calls waitpid; so this function then generates an error.
 312           I've commented out the wxLogSysError and the 'else' so that
 313           termination is always done properly.
 314        */
 315     }
 316     // else
 317     {
 318         // notify user about termination if required
 319         if (proc_data->process)
 320         {
 321             proc_data->process->OnTerminate(proc_data->pid,
 322                                             WEXITSTATUS(status));
 323         }
 324         // clean up
 325         if ( proc_data->pid > 0 )
 326         {
 327            delete proc_data;
 328         }
 329         else
 330         {
 331            // wxExecute() will know about it
 332            proc_data->exitcode = status;
 333
 334            proc_data->pid = 0;
 335         }
 336     }
 337 }
 338
 339 #endif // wxUSE_GUI
 340
 341 // ----------------------------------------------------------------------------
 342 // wxStream classes to support IO redirection in wxExecute
 343 // ----------------------------------------------------------------------------
 344
 345 #if wxUSE_STREAMS
 346
 347 class wxProcessFileInputStream : public wxInputStream
 348 {
 349 public:
 350     wxProcessFileInputStream(int fd) { m_fd = fd; }
 351     ~wxProcessFileInputStream() { close(m_fd); }
 352
 353     virtual bool Eof() const;
 354
 355 protected:
 356     size_t OnSysRead(void *buffer, size_t bufsize);
 357
 358 protected:
 359     int m_fd;
 360 };
 361
 362 class wxProcessFileOutputStream : public wxOutputStream
 363 {
 364 public:
 365     wxProcessFileOutputStream(int fd) { m_fd = fd; }
 366     ~wxProcessFileOutputStream() { close(m_fd); }
 367
 368 protected:
 369     size_t OnSysWrite(const void *buffer, size_t bufsize);
 370
 371 protected:
 372     int m_fd;
 373 };
 374
 375 bool wxProcessFileInputStream::Eof() const
 376 {
 377     if ( m_lasterror == wxSTREAM_EOF )
 378         return TRUE;
 379
 380     // check if there is any input available
 381     struct timeval tv;
 382     tv.tv_sec = 0;
 383     tv.tv_usec = 0;
 384
 385     fd_set readfds;
 386     FD_ZERO(&readfds);
 387     FD_SET(m_fd, &readfds);
 388     switch ( select(m_fd + 1, &readfds, NULL, NULL, &tv) )
 389     {
 390         case -1:
 391             wxLogSysError(_("Impossible to get child process input"));
 392             // fall through
 393
 394         case 0:
 395             return TRUE;
 396
 397         default:
 398             wxFAIL_MSG(_T("unexpected select() return value"));
 399             // still fall through
 400
 401         case 1:
 402             // input available: check if there is any
 403             return wxInputStream::Eof();
 404     }
 405 }
 406
 407 size_t wxProcessFileInputStream::OnSysRead(void *buffer, size_t bufsize)
 408 {
 409     int ret = read(m_fd, buffer, bufsize);
 410     if ( ret == 0 )
 411     {
 412         m_lasterror = wxSTREAM_EOF;
 413     }
 414     else if ( ret == -1 )
 415     {
 416         m_lasterror = wxSTREAM_READ_ERROR;
 417         ret = 0;
 418     }
 419     else
 420     {
 421         m_lasterror = wxSTREAM_NOERROR;
 422     }
 423
 424     return ret;
 425 }
 426
 427 size_t wxProcessFileOutputStream::OnSysWrite(const void *buffer, size_t bufsize)
 428 {
 429     int ret = write(m_fd, buffer, bufsize);
 430     if ( ret == -1 )
 431     {
 432         m_lasterror = wxSTREAM_WRITE_ERROR;
 433         ret = 0;
 434     }
 435     else
 436     {
 437         m_lasterror = wxSTREAM_NOERROR;
 438     }
 439
 440     return ret;
 441 }
 442
 443 #endif // wxUSE_STREAMS
 444
 445 long wxExecute(wxChar **argv,
 446                bool sync,
 447                wxProcess *process)
 448 {
 449     // for the sync execution, we return -1 to indicate failure, but for async
 450     // case we return 0 which is never a valid PID
 451     //
 452     // we define this as a macro, not a variable, to avoid compiler warnings
 453     // about "ERROR_RETURN_CODE value may be clobbered by fork()"
 454     #define ERROR_RETURN_CODE ((sync) ? -1 : 0)
 455
 456     wxCHECK_MSG( *argv, ERROR_RETURN_CODE, wxT("can't exec empty command") );
 457
 458 #if wxUSE_UNICODE
 459     int mb_argc = 0;
 460     char *mb_argv[WXEXECUTE_NARGS];
 461
 462     while (argv[mb_argc])
 463     {
 464         wxWX2MBbuf mb_arg = wxConvertWX2MB(argv[mb_argc]);
 465         mb_argv[mb_argc] = strdup(mb_arg);
 466         mb_argc++;
 467     }
 468     mb_argv[mb_argc] = (char *) NULL;
 469
 470     // this macro will free memory we used above
 471     #define ARGS_CLEANUP                                 \
 472         for ( mb_argc = 0; mb_argv[mb_argc]; mb_argc++ ) \
 473             free(mb_argv[mb_argc])
 474 #else // ANSI
 475     // no need for cleanup
 476     #define ARGS_CLEANUP
 477
 478     wxChar **mb_argv = argv;
 479 #endif // Unicode/ANSI
 480
 481 #if wxUSE_GUI
 482     // create pipes
 483     int end_proc_detect[2];
 484     if ( pipe(end_proc_detect) == -1 )
 485     {
 486         wxLogSysError( _("Pipe creation failed") );
 487         wxLogError( _("Failed to execute '%s'\n"), *argv );
 488
 489         ARGS_CLEANUP;
 490
 491         return ERROR_RETURN_CODE;
 492     }
 493 #endif // wxUSE_GUI
 494
 495     // pipes for inter process communication
 496     int pipeIn[2],      // stdin
 497         pipeOut[2],     // stdout
 498         pipeErr[2];     // stderr
 499
 500     pipeIn[0] = pipeIn[1] =
 501     pipeOut[0] = pipeOut[1] =
 502     pipeErr[0] = pipeErr[1] = -1;
 503
 504     if ( process && process->IsRedirected() )
 505     {
 506         if ( pipe(pipeIn) == -1 || pipe(pipeOut) == -1 || pipe(pipeErr) == -1 )
 507         {
 508 #if wxUSE_GUI
 509             // free previously allocated resources
 510             close(end_proc_detect[0]);
 511             close(end_proc_detect[1]);
 512 #endif // wxUSE_GUI
 513
 514             wxLogSysError( _("Pipe creation failed") );
 515             wxLogError( _("Failed to execute '%s'\n"), *argv );
 516
 517             ARGS_CLEANUP;
 518
 519             return ERROR_RETURN_CODE;
 520         }
 521     }
 522
 523     // fork the process
 524 #ifdef HAVE_VFORK
 525     pid_t pid = vfork();
 526 #else
 527     pid_t pid = fork();
 528 #endif
 529
 530     if ( pid == -1 )     // error?
 531     {
 532 #if wxUSE_GUI
 533         close(end_proc_detect[0]);
 534         close(end_proc_detect[1]);
 535         close(pipeIn[0]);
 536         close(pipeIn[1]);
 537         close(pipeOut[0]);
 538         close(pipeOut[1]);
 539         close(pipeErr[0]);
 540         close(pipeErr[1]);
 541 #endif // wxUSE_GUI
 542
 543         wxLogSysError( _("Fork failed") );
 544
 545         ARGS_CLEANUP;
 546
 547         return ERROR_RETURN_CODE;
 548     }
 549     else if ( pid == 0 )  // we're in child
 550     {
 551 #if wxUSE_GUI
 552         close(end_proc_detect[0]); // close reading side
 553 #endif // wxUSE_GUI
 554
 555         // These lines close the open file descriptors to to avoid any
 556         // input/output which might block the process or irritate the user. If
 557         // one wants proper IO for the subprocess, the right thing to do is to
 558         // start an xterm executing it.
 559         if ( !sync )
 560         {
 561             for ( int fd = 0; fd < FD_SETSIZE; fd++ )
 562             {
 563                 if ( fd == pipeIn[0] || fd == pipeOut[1] || fd == pipeErr[1]
 564 #if wxUSE_GUI
 565                      || fd == end_proc_detect[1]
 566 #endif // wxUSE_GUI
 567                    )
 568                 {
 569                     // don't close this one, we still need it
 570                     continue;
 571                 }
 572
 573                 // leave stderr opened too, it won't do any hurm
 574                 if ( fd != STDERR_FILENO )
 575                     close(fd);
 576             }
 577         }
 578
 579         // redirect stdio, stdout and stderr
 580         if ( pipeIn[0] != -1 )
 581         {
 582             if ( dup2(pipeIn[0], STDIN_FILENO) == -1 ||
 583                  dup2(pipeOut[1], STDOUT_FILENO) == -1 ||
 584                  dup2(pipeErr[1], STDERR_FILENO) == -1 )
 585             {
 586                 wxLogSysError(_("Failed to redirect child process input/output"));
 587             }
 588
 589             close(pipeIn[0]);
 590             close(pipeOut[1]);
 591             close(pipeErr[1]);
 592         }
 593
 594         execvp (*mb_argv, mb_argv);
 595
 596         // there is no return after successful exec()
 597         _exit(-1);
 598     }
 599     else // we're in parent
 600     {
 601         ARGS_CLEANUP;
 602
 603         // pipe initialization: construction of the wxStreams
 604         if ( process && process->IsRedirected() )
 605         {
 606 #if wxUSE_STREAMS
 607             // These two streams are relative to this process.
 608             wxOutputStream *outStream = new wxProcessFileOutputStream(pipeIn[1]);
 609             wxInputStream *inStream = new wxProcessFileInputStream(pipeOut[0]);
 610             wxInputStream *errStream = new wxProcessFileInputStream(pipeErr[0]);
 611
 612             process->SetPipeStreams(inStream, outStream, errStream);
 613 #endif // wxUSE_STREAMS
 614
 615             close(pipeIn[0]); // close reading side
 616             close(pipeOut[1]); // close writing side
 617             close(pipeErr[1]); // close writing side
 618         }
 619
 620 #if wxUSE_GUI && !defined(__WXMICROWIN__)
 621         wxEndProcessData *data = new wxEndProcessData;
 622
 623         if ( sync )
 624         {
 625             // we may have process for capturing the program output, but it's
 626             // not used in wxEndProcessData in the case of sync execution
 627             data->process = NULL;
 628
 629             // sync execution: indicate it by negating the pid
 630             data->pid = -pid;
 631             data->tag = wxAddProcessCallback(data, end_proc_detect[0]);
 632
 633             close(end_proc_detect[1]); // close writing side
 634
 635             wxBusyCursor bc;
 636             wxWindowDisabler wd;
 637
 638             // it will be set to 0 from GTK_EndProcessDetector
 639             while (data->pid != 0)
 640                 wxYield();
 641
 642             int exitcode = data->exitcode;
 643
 644             delete data;
 645
 646             return exitcode;
 647         }
 648         else // async execution
 649         {
 650             // async execution, nothing special to do - caller will be
 651             // notified about the process termination if process != NULL, data
 652             // will be deleted in GTK_EndProcessDetector
 653             data->process  = process;
 654             data->pid      = pid;
 655             data->tag      = wxAddProcessCallback(data, end_proc_detect[0]);
 656
 657             close(end_proc_detect[1]); // close writing side
 658
 659             return pid;
 660         }
 661 #else // !wxUSE_GUI
 662         wxASSERT_MSG( sync, wxT("async execution not supported yet") );
 663
 664         int exitcode = 0;
 665         if ( waitpid(pid, &exitcode, 0) == -1 || !WIFEXITED(exitcode) )
 666         {
 667             wxLogSysError(_("Waiting for subprocess termination failed"));
 668         }
 669
 670         return exitcode;
 671 #endif // wxUSE_GUI
 672     }
 673 #ifdef __VMS
 674    // VMS does not recognise exit as a return and complains about
 675    // a missing return
 676    // I think VMS is wrong in this
 677    //     JJ
 678    return 0;
 679 #endif
 680 }
 681
 682 #undef ERROR_RETURN_CODE
 683 #undef ARGS_CLEANUP
 684
 685 // ----------------------------------------------------------------------------
 686 // file and directory functions
 687 // ----------------------------------------------------------------------------
 688
 689 const wxChar* wxGetHomeDir( wxString *home  )
 690 {
 691     *home = wxGetUserHome( wxString() );
 692    wxString tmp;
 693     if ( home->IsEmpty() )
 694         *home = wxT("/");
 695 #ifdef __VMS
 696    tmp = *home;
 697    if ( tmp.Last() != wxT(']'))
 698      if ( tmp.Last() != wxT('/')) *home << wxT('/');
 699 #endif
 700     return home->c_str();
 701 }
 702
 703 #if wxUSE_UNICODE
 704 const wxMB2WXbuf wxGetUserHome( const wxString &user )
 705 #else // just for binary compatibility -- there is no 'const' here
 706 char *wxGetUserHome( const wxString &user )
 707 #endif
 708 {
 709     struct passwd *who = (struct passwd *) NULL;
 710
 711     if ( !user )
 712     {
 713         wxChar *ptr;
 714
 715         if ((ptr = wxGetenv(wxT("HOME"))) != NULL)
 716         {
 717             return ptr;
 718         }
 719         if ((ptr = wxGetenv(wxT("USER"))) != NULL || (ptr = wxGetenv(wxT("LOGNAME"))) != NULL)
 720         {
 721             who = getpwnam(wxConvertWX2MB(ptr));
 722         }
 723
 724         // We now make sure the the user exists!
 725         if (who == NULL)
 726         {
 727             who = getpwuid(getuid());
 728         }
 729     }
 730     else
 731     {
 732       who = getpwnam (user.mb_str());
 733     }
 734
 735     return wxConvertMB2WX(who ? who->pw_dir : 0);
 736 }
 737
 738 // ----------------------------------------------------------------------------
 739 // network and user id routines
 740 // ----------------------------------------------------------------------------
 741
 742 // retrieve either the hostname or FQDN depending on platform (caller must
 743 // check whether it's one or the other, this is why this function is for
 744 // private use only)
 745 static bool wxGetHostNameInternal(wxChar *buf, int sz)
 746 {
 747     wxCHECK_MSG( buf, FALSE, wxT("NULL pointer in wxGetHostNameInternal") );
 748
 749     *buf = wxT('\0');
 750
 751     // we're using uname() which is POSIX instead of less standard sysinfo()
 752 #if defined(HAVE_UNAME)
 753     struct utsname uts;
 754     bool ok = uname(&uts) != -1;
 755     if ( ok )
 756     {
 757         wxStrncpy(buf, wxConvertMB2WX(uts.nodename), sz - 1);
 758         buf[sz] = wxT('\0');
 759     }
 760 #elif defined(HAVE_GETHOSTNAME)
 761     bool ok = gethostname(buf, sz) != -1;
 762 #else // no uname, no gethostname
 763     wxFAIL_MSG(wxT("don't know host name for this machine"));
 764
 765     bool ok = FALSE;
 766 #endif // uname/gethostname
 767
 768     if ( !ok )
 769     {
 770         wxLogSysError(_("Cannot get the hostname"));
 771     }
 772
 773     return ok;
 774 }
 775
 776 bool wxGetHostName(wxChar *buf, int sz)
 777 {
 778     bool ok = wxGetHostNameInternal(buf, sz);
 779
 780     if ( ok )
 781     {
 782         // BSD systems return the FQDN, we only want the hostname, so extract
 783         // it (we consider that dots are domain separators)
 784         wxChar *dot = wxStrchr(buf, wxT('.'));
 785         if ( dot )
 786         {
 787             // nuke it
 788             *dot = wxT('\0');
 789         }
 790     }
 791
 792     return ok;
 793 }
 794
 795 bool wxGetFullHostName(wxChar *buf, int sz)
 796 {
 797     bool ok = wxGetHostNameInternal(buf, sz);
 798
 799     if ( ok )
 800     {
 801         if ( !wxStrchr(buf, wxT('.')) )
 802         {
 803             struct hostent *host = gethostbyname(wxConvertWX2MB(buf));
 804             if ( !host )
 805             {
 806                 wxLogSysError(_("Cannot get the official hostname"));
 807
 808                 ok = FALSE;
 809             }
 810             else
 811             {
 812                 // the canonical name
 813                 wxStrncpy(buf, wxConvertMB2WX(host->h_name), sz);
 814             }
 815         }
 816         //else: it's already a FQDN (BSD behaves this way)
 817     }
 818
 819     return ok;
 820 }
 821
 822 bool wxGetUserId(wxChar *buf, int sz)
 823 {
 824     struct passwd *who;
 825
 826     *buf = wxT('\0');
 827     if ((who = getpwuid(getuid ())) != NULL)
 828     {
 829         wxStrncpy (buf, wxConvertMB2WX(who->pw_name), sz - 1);
 830         return TRUE;
 831     }
 832
 833     return FALSE;
 834 }
 835
 836 bool wxGetUserName(wxChar *buf, int sz)
 837 {
 838     struct passwd *who;
 839
 840     *buf = wxT('\0');
 841     if ((who = getpwuid (getuid ())) != NULL)
 842     {
 843         // pw_gecos field in struct passwd is not standard
 844 #ifdef HAVE_PW_GECOS
 845        char *comma = strchr(who->pw_gecos, ',');
 846        if (comma)
 847            *comma = '\0'; // cut off non-name comment fields
 848        wxStrncpy (buf, wxConvertMB2WX(who->pw_gecos), sz - 1);
 849 #else // !HAVE_PW_GECOS
 850        wxStrncpy (buf, wxConvertMB2WX(who->pw_name), sz - 1);
 851 #endif // HAVE_PW_GECOS/!HAVE_PW_GECOS
 852        return TRUE;
 853     }
 854
 855     return FALSE;
 856 }
 857
 858 wxString wxGetOsDescription()
 859 {
 860 #ifndef WXWIN_OS_DESCRIPTION
 861     #error WXWIN_OS_DESCRIPTION should be defined in config.h by configure
 862 #else
 863     return WXWIN_OS_DESCRIPTION;
 864 #endif
 865 }
 866
 867 // this function returns the GUI toolkit version in GUI programs, but OS
 868 // version in non-GUI ones
 869 #if !wxUSE_GUI
 870
 871 int wxGetOsVersion(int *majorVsn, int *minorVsn)
 872 {
 873     int major, minor;
 874     char name[256];
 875
 876     if ( sscanf(WXWIN_OS_DESCRIPTION, "%s %d.%d", name, &major, &minor) != 3 )
 877     {
 878         // unreckognized uname string format
 879         major = minor = -1;
 880     }
 881
 882     if ( majorVsn )
 883         *majorVsn = major;
 884     if ( minorVsn )
 885         *minorVsn = minor;
 886
 887     return wxUNIX;
 888 }
 889
 890 #endif // !wxUSE_GUI
 891
 892 long wxGetFreeMemory()
 893 {
 894 #if defined(__LINUX__)
 895     // get it from /proc/meminfo
 896     FILE *fp = fopen("/proc/meminfo", "r");
 897     if ( fp )
 898     {
 899         long memFree = -1;
 900
 901         char buf[1024];
 902         if ( fgets(buf, WXSIZEOF(buf), fp) && fgets(buf, WXSIZEOF(buf), fp) )
 903         {
 904             long memTotal, memUsed;
 905             sscanf(buf, "Mem: %ld %ld %ld", &memTotal, &memUsed, &memFree);
 906         }
 907
 908         fclose(fp);
 909
 910         return memFree;
 911     }
 912 #elif defined(__SUN__) && defined(_SC_AVPHYS_PAGES)
 913     return sysconf(_SC_AVPHYS_PAGES)*sysconf(_SC_PAGESIZE);
 914 //#elif defined(__FREEBSD__) -- might use sysctl() to find it out, probably
 915 #endif
 916
 917     // can't find it out
 918     return -1;
 919 }
 920
 921 bool wxGetDiskSpace(const wxString& path, wxLongLong *pTotal, wxLongLong *pFree)
 922 {
 923 #ifdef HAVE_STATFS
 924
 925     struct statfs fs;
 926     if ( statfs(path, &fs) != 0 )
 927     {
 928         wxLogSysError("Failed to get file system statistics");
 929
 930         return FALSE;
 931     }
 932
 933     if ( pTotal )
 934     {
 935         *pTotal = wxLongLong(fs.f_blocks) * fs.f_bsize;
 936     }
 937
 938     if ( pFree )
 939     {
 940         *pFree = wxLongLong(fs.f_bavail) * fs.f_bsize;
 941     }
 942
 943     return TRUE;
 944 #endif // HAVE_STATFS
 945
 946     return FALSE;
 947 }
 948
 949 // ----------------------------------------------------------------------------
 950 // env vars
 951 // ----------------------------------------------------------------------------
 952
 953 bool wxGetEnv(const wxString& var, wxString *value)
 954 {
 955     // wxGetenv is defined as getenv()
 956     wxChar *p = wxGetenv(var);
 957     if ( !p )
 958         return FALSE;
 959
 960     if ( value )
 961     {
 962         *value = p;
 963     }
 964
 965     return TRUE;
 966 }
 967
 968 bool wxSetEnv(const wxString& variable, const wxChar *value)
 969 {
 970 #if defined(HAVE_SETENV)
 971     return setenv(variable.mb_str(), value ? wxString(value).mb_str().data()
 972                                            : NULL, 1 /* overwrite */) == 0;
 973 #elif defined(HAVE_PUTENV)
 974     wxString s = variable;
 975     if ( value )
 976         s << _T('=') << value;
 977
 978     // transform to ANSI
 979     const char *p = s.mb_str();
 980
 981     // the string will be free()d by libc
 982     char *buf = (char *)malloc(strlen(p) + 1);
 983     strcpy(buf, p);
 984
 985     return putenv(buf) == 0;
 986 #else // no way to set an env var
 987     return FALSE;
 988 #endif
 989 }
 990
 991 // ----------------------------------------------------------------------------
 992 // signal handling
 993 // ----------------------------------------------------------------------------
 994
 995 #if wxUSE_ON_FATAL_EXCEPTION
 996
 997 #include <signal.h>
 998
 999 static void wxFatalSignalHandler(wxTYPE_SA_HANDLER)
1000 {
1001     if ( wxTheApp )
1002     {
1003         // give the user a chance to do something special about this
1004         wxTheApp->OnFatalException();
1005     }
1006
1007     abort();
1008 }
1009
1010 bool wxHandleFatalExceptions(bool doit)
1011 {
1012     // old sig handlers
1013     static bool s_savedHandlers = FALSE;
1014     static struct sigaction s_handlerFPE,
1015                             s_handlerILL,
1016                             s_handlerBUS,
1017                             s_handlerSEGV;
1018
1019     bool ok = TRUE;
1020     if ( doit && !s_savedHandlers )
1021     {
1022         // install the signal handler
1023         struct sigaction act;
1024
1025         // some systems extend it with non std fields, so zero everything
1026         memset(&act, 0, sizeof(act));
1027
1028         act.sa_handler = wxFatalSignalHandler;
1029         sigemptyset(&act.sa_mask);
1030         act.sa_flags = 0;
1031
1032         ok &= sigaction(SIGFPE, &act, &s_handlerFPE) == 0;
1033         ok &= sigaction(SIGILL, &act, &s_handlerILL) == 0;
1034         ok &= sigaction(SIGBUS, &act, &s_handlerBUS) == 0;
1035         ok &= sigaction(SIGSEGV, &act, &s_handlerSEGV) == 0;
1036         if ( !ok )
1037         {
1038             wxLogDebug(_T("Failed to install our signal handler."));
1039         }
1040
1041         s_savedHandlers = TRUE;
1042     }
1043     else if ( s_savedHandlers )
1044     {
1045         // uninstall the signal handler
1046         ok &= sigaction(SIGFPE, &s_handlerFPE, NULL) == 0;
1047         ok &= sigaction(SIGILL, &s_handlerILL, NULL) == 0;
1048         ok &= sigaction(SIGBUS, &s_handlerBUS, NULL) == 0;
1049         ok &= sigaction(SIGSEGV, &s_handlerSEGV, NULL) == 0;
1050         if ( !ok )
1051         {
1052             wxLogDebug(_T("Failed to uninstall our signal handler."));
1053         }
1054
1055         s_savedHandlers = FALSE;
1056     }
1057     //else: nothing to do
1058
1059     return ok;
1060 }
1061
1062 #endif // wxUSE_ON_FATAL_EXCEPTION
1063
1064 // ----------------------------------------------------------------------------
1065 // error and debug output routines (deprecated, use wxLog)
1066 // ----------------------------------------------------------------------------
1067
1068 void wxDebugMsg( const char *format, ... )
1069 {
1070   va_list ap;
1071   va_start( ap, format );
1072   vfprintf( stderr, format, ap );
1073   fflush( stderr );
1074   va_end(ap);
1075 }
1076
1077 void wxError( const wxString &msg, const wxString &title )
1078 {
1079   wxFprintf( stderr, _("Error ") );
1080   if (!title.IsNull()) wxFprintf( stderr, wxT("%s "), WXSTRINGCAST(title) );
1081   if (!msg.IsNull()) wxFprintf( stderr, wxT(": %s"), WXSTRINGCAST(msg) );
1082   wxFprintf( stderr, wxT(".\n") );
1083 }
1084
1085 void wxFatalError( const wxString &msg, const wxString &title )
1086 {
1087   wxFprintf( stderr, _("Error ") );
1088   if (!title.IsNull()) wxFprintf( stderr, wxT("%s "), WXSTRINGCAST(title) );
1089   if (!msg.IsNull()) wxFprintf( stderr, wxT(": %s"), WXSTRINGCAST(msg) );
1090   wxFprintf( stderr, wxT(".\n") );
1091   exit(3); // the same exit code as for abort()
1092 }
1093