src/unix/utilsunx.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/unix/utilsunx.cpp
   3 // Purpose:     generic Unix implementation of many wx functions (for wxBase)
   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 // for compilers that support precompilation, includes "wx.h".
  19 #include "wx/wxprec.h"
  20
  21 #include "wx/utils.h"
  22
  23 #define USE_PUTENV (!defined(HAVE_SETENV) && defined(HAVE_PUTENV))
  24
  25 #ifndef WX_PRECOMP
  26     #include "wx/string.h"
  27     #include "wx/intl.h"
  28     #include "wx/log.h"
  29     #include "wx/app.h"
  30     #include "wx/wxcrtvararg.h"
  31     #if USE_PUTENV
  32         #include "wx/module.h"
  33         #include "wx/hashmap.h"
  34     #endif
  35 #endif
  36
  37 #include "wx/apptrait.h"
  38
  39 #include "wx/process.h"
  40 #include "wx/thread.h"
  41
  42 #include "wx/cmdline.h"
  43
  44 #include "wx/wfstream.h"
  45
  46 #include "wx/private/selectdispatcher.h"
  47 #include "wx/private/fdiodispatcher.h"
  48 #include "wx/unix/execute.h"
  49 #include "wx/unix/private.h"
  50
  51 #ifdef wxHAS_GENERIC_PROCESS_CALLBACK
  52 #include "wx/private/fdiodispatcher.h"
  53 #endif
  54
  55 #include <pwd.h>
  56 #include <sys/wait.h>       // waitpid()
  57
  58 #ifdef HAVE_SYS_SELECT_H
  59 #   include <sys/select.h>
  60 #endif
  61
  62 #define HAS_PIPE_INPUT_STREAM (wxUSE_STREAMS && wxUSE_FILE)
  63
  64 #if HAS_PIPE_INPUT_STREAM
  65
  66 // define this to let wxexec.cpp know that we know what we're doing
  67 #define _WX_USED_BY_WXEXECUTE_
  68 #include "../common/execcmn.cpp"
  69
  70 #endif // HAS_PIPE_INPUT_STREAM
  71
  72 #if defined(__MWERKS__) && defined(__MACH__)
  73     #ifndef WXWIN_OS_DESCRIPTION
  74         #define WXWIN_OS_DESCRIPTION "MacOS X"
  75     #endif
  76     #ifndef HAVE_NANOSLEEP
  77         #define HAVE_NANOSLEEP
  78     #endif
  79     #ifndef HAVE_UNAME
  80         #define HAVE_UNAME
  81     #endif
  82
  83     // our configure test believes we can use sigaction() if the function is
  84     // available but Metrowekrs with MSL run-time does have the function but
  85     // doesn't have sigaction struct so finally we can't use it...
  86     #ifdef __MSL__
  87         #undef wxUSE_ON_FATAL_EXCEPTION
  88         #define wxUSE_ON_FATAL_EXCEPTION 0
  89     #endif
  90 #endif
  91
  92 // not only the statfs syscall is called differently depending on platform, but
  93 // one of its incarnations, statvfs(), takes different arguments under
  94 // different platforms and even different versions of the same system (Solaris
  95 // 7 and 8): if you want to test for this, don't forget that the problems only
  96 // appear if the large files support is enabled
  97 #ifdef HAVE_STATFS
  98     #ifdef __BSD__
  99         #include <sys/param.h>
 100         #include <sys/mount.h>
 101     #else // !__BSD__
 102         #include <sys/vfs.h>
 103     #endif // __BSD__/!__BSD__
 104
 105     #define wxStatfs statfs
 106
 107     #ifndef HAVE_STATFS_DECL
 108         // some systems lack statfs() prototype in the system headers (AIX 4)
 109         extern "C" int statfs(const char *path, struct statfs *buf);
 110     #endif
 111 #endif // HAVE_STATFS
 112
 113 #ifdef HAVE_STATVFS
 114     #include <sys/statvfs.h>
 115
 116     #define wxStatfs statvfs
 117 #endif // HAVE_STATVFS
 118
 119 #if defined(HAVE_STATFS) || defined(HAVE_STATVFS)
 120     // WX_STATFS_T is detected by configure
 121     #define wxStatfs_t WX_STATFS_T
 122 #endif
 123
 124 // SGI signal.h defines signal handler arguments differently depending on
 125 // whether _LANGUAGE_C_PLUS_PLUS is set or not - do set it
 126 #if defined(__SGI__) && !defined(_LANGUAGE_C_PLUS_PLUS)
 127     #define _LANGUAGE_C_PLUS_PLUS 1
 128 #endif // SGI hack
 129
 130 #include <stdarg.h>
 131 #include <dirent.h>
 132 #include <string.h>
 133 #include <sys/stat.h>
 134 #include <sys/types.h>
 135 #include <sys/wait.h>
 136 #include <unistd.h>
 137 #include <errno.h>
 138 #include <netdb.h>
 139 #include <signal.h>
 140 #include <fcntl.h>          // for O_WRONLY and friends
 141 #include <time.h>           // nanosleep() and/or usleep()
 142 #include <ctype.h>          // isspace()
 143 #include <sys/time.h>       // needed for FD_SETSIZE
 144
 145 #ifdef HAVE_UNAME
 146     #include <sys/utsname.h> // for uname()
 147 #endif // HAVE_UNAME
 148
 149 // Used by wxGetFreeMemory().
 150 #ifdef __SGI__
 151     #include <sys/sysmp.h>
 152     #include <sys/sysinfo.h>   // for SAGET and MINFO structures
 153 #endif
 154
 155 // ----------------------------------------------------------------------------
 156 // conditional compilation
 157 // ----------------------------------------------------------------------------
 158
 159 // many versions of Unices have this function, but it is not defined in system
 160 // headers - please add your system here if it is the case for your OS.
 161 // SunOS < 5.6 (i.e. Solaris < 2.6) and DG-UX are like this.
 162 #if !defined(HAVE_USLEEP) && \
 163     ((defined(__SUN__) && !defined(__SunOs_5_6) && \
 164                          !defined(__SunOs_5_7) && !defined(__SUNPRO_CC)) || \
 165      defined(__osf__) || defined(__EMX__))
 166     extern "C"
 167     {
 168         #ifdef __EMX__
 169             /* I copied this from the XFree86 diffs. AV. */
 170             #define INCL_DOSPROCESS
 171             #include <os2.h>
 172             inline void usleep(unsigned long delay)
 173             {
 174                 DosSleep(delay ? (delay/1000l) : 1l);
 175             }
 176         #else // Unix
 177             int usleep(unsigned int usec);
 178         #endif // __EMX__/Unix
 179     };
 180
 181     #define HAVE_USLEEP 1
 182 #endif // Unices without usleep()
 183
 184 // ============================================================================
 185 // implementation
 186 // ============================================================================
 187
 188 // ----------------------------------------------------------------------------
 189 // sleeping
 190 // ----------------------------------------------------------------------------
 191
 192 void wxSleep(int nSecs)
 193 {
 194     sleep(nSecs);
 195 }
 196
 197 void wxMicroSleep(unsigned long microseconds)
 198 {
 199 #if defined(HAVE_NANOSLEEP)
 200     timespec tmReq;
 201     tmReq.tv_sec = (time_t)(microseconds / 1000000);
 202     tmReq.tv_nsec = (microseconds % 1000000) * 1000;
 203
 204     // we're not interested in remaining time nor in return value
 205     (void)nanosleep(&tmReq, NULL);
 206 #elif defined(HAVE_USLEEP)
 207     // uncomment this if you feel brave or if you are sure that your version
 208     // of Solaris has a safe usleep() function but please notice that usleep()
 209     // is known to lead to crashes in MT programs in Solaris 2.[67] and is not
 210     // documented as MT-Safe
 211     #if defined(__SUN__) && wxUSE_THREADS
 212         #error "usleep() cannot be used in MT programs under Solaris."
 213     #endif // Sun
 214
 215     usleep(microseconds);
 216 #elif defined(HAVE_SLEEP)
 217     // under BeOS sleep() takes seconds (what about other platforms, if any?)
 218     sleep(microseconds * 1000000);
 219 #else // !sleep function
 220     #error "usleep() or nanosleep() function required for wxMicroSleep"
 221 #endif // sleep function
 222 }
 223
 224 void wxMilliSleep(unsigned long milliseconds)
 225 {
 226     wxMicroSleep(milliseconds*1000);
 227 }
 228
 229 // ----------------------------------------------------------------------------
 230 // process management
 231 // ----------------------------------------------------------------------------
 232
 233 int wxKill(long pid, wxSignal sig, wxKillError *rc, int flags)
 234 {
 235     int err = kill((pid_t) (flags & wxKILL_CHILDREN) ? -pid : pid, (int)sig);
 236     if ( rc )
 237     {
 238         switch ( err ? errno : 0 )
 239         {
 240             case 0:
 241                 *rc = wxKILL_OK;
 242                 break;
 243
 244             case EINVAL:
 245                 *rc = wxKILL_BAD_SIGNAL;
 246                 break;
 247
 248             case EPERM:
 249                 *rc = wxKILL_ACCESS_DENIED;
 250                 break;
 251
 252             case ESRCH:
 253                 *rc = wxKILL_NO_PROCESS;
 254                 break;
 255
 256             default:
 257                 // this goes against Unix98 docs so log it
 258                 wxLogDebug(_T("unexpected kill(2) return value %d"), err);
 259
 260                 // something else...
 261                 *rc = wxKILL_ERROR;
 262         }
 263     }
 264
 265     return err;
 266 }
 267
 268 // Shutdown or reboot the PC
 269 bool wxShutdown(int flags)
 270 {
 271     flags &= ~wxSHUTDOWN_FORCE;
 272
 273     wxChar level;
 274     switch ( flags )
 275     {
 276         case wxSHUTDOWN_POWEROFF:
 277             level = _T('0');
 278             break;
 279
 280         case wxSHUTDOWN_REBOOT:
 281             level = _T('6');
 282             break;
 283
 284         case wxSHUTDOWN_LOGOFF:
 285             // TODO: use dcop to log off?
 286             return false;
 287
 288         default:
 289             wxFAIL_MSG( _T("unknown wxShutdown() flag") );
 290             return false;
 291     }
 292
 293     return system(wxString::Format("init %c", level).mb_str()) == 0;
 294 }
 295
 296 // ----------------------------------------------------------------------------
 297 // wxStream classes to support IO redirection in wxExecute
 298 // ----------------------------------------------------------------------------
 299
 300 #if HAS_PIPE_INPUT_STREAM
 301
 302 bool wxPipeInputStream::CanRead() const
 303 {
 304     if ( m_lasterror == wxSTREAM_EOF )
 305         return false;
 306
 307     // check if there is any input available
 308     struct timeval tv;
 309     tv.tv_sec = 0;
 310     tv.tv_usec = 0;
 311
 312     const int fd = m_file->fd();
 313
 314     fd_set readfds;
 315
 316     wxFD_ZERO(&readfds);
 317     wxFD_SET(fd, &readfds);
 318
 319     switch ( select(fd + 1, &readfds, NULL, NULL, &tv) )
 320     {
 321         case -1:
 322             wxLogSysError(_("Impossible to get child process input"));
 323             // fall through
 324
 325         case 0:
 326             return false;
 327
 328         default:
 329             wxFAIL_MSG(_T("unexpected select() return value"));
 330             // still fall through
 331
 332         case 1:
 333             // input available -- or maybe not, as select() returns 1 when a
 334             // read() will complete without delay, but it could still not read
 335             // anything
 336             return !Eof();
 337     }
 338 }
 339
 340 #endif // HAS_PIPE_INPUT_STREAM
 341
 342 // ----------------------------------------------------------------------------
 343 // wxShell
 344 // ----------------------------------------------------------------------------
 345
 346 static wxString wxMakeShellCommand(const wxString& command)
 347 {
 348     wxString cmd;
 349     if ( !command )
 350     {
 351         // just an interactive shell
 352         cmd = _T("xterm");
 353     }
 354     else
 355     {
 356         // execute command in a shell
 357         cmd << _T("/bin/sh -c '") << command << _T('\'');
 358     }
 359
 360     return cmd;
 361 }
 362
 363 bool wxShell(const wxString& command)
 364 {
 365     return wxExecute(wxMakeShellCommand(command), wxEXEC_SYNC) == 0;
 366 }
 367
 368 bool wxShell(const wxString& command, wxArrayString& output)
 369 {
 370     wxCHECK_MSG( !command.empty(), false, _T("can't exec shell non interactively") );
 371
 372     return wxExecute(wxMakeShellCommand(command), output);
 373 }
 374
 375 namespace
 376 {
 377
 378 // helper class for storing arguments as char** array suitable for passing to
 379 // execvp(), whatever form they were passed to us
 380 class ArgsArray
 381 {
 382 public:
 383     ArgsArray(const wxArrayString& args)
 384     {
 385         Init(args.size());
 386
 387         for ( int i = 0; i < m_argc; i++ )
 388         {
 389             m_argv[i] = wxStrdup(args[i]);
 390         }
 391     }
 392
 393 #if wxUSE_UNICODE
 394     ArgsArray(wchar_t **wargv)
 395     {
 396         int argc = 0;
 397         while ( *wargv++ )
 398             argc++;
 399
 400         Init(argc);
 401
 402         for ( int i = 0; i < m_argc; i++ )
 403         {
 404             m_argv[i] = wxSafeConvertWX2MB(wargv[i]).release();
 405         }
 406     }
 407 #endif // wxUSE_UNICODE
 408
 409     ~ArgsArray()
 410     {
 411         for ( int i = 0; i < m_argc; i++ )
 412         {
 413             free(m_argv[i]);
 414         }
 415
 416         delete [] m_argv;
 417     }
 418
 419     operator char**() const { return m_argv; }
 420
 421 private:
 422     void Init(int argc)
 423     {
 424         m_argc = argc;
 425         m_argv = new char *[m_argc + 1];
 426         m_argv[m_argc] = NULL;
 427     }
 428
 429     int m_argc;
 430     char **m_argv;
 431
 432     wxDECLARE_NO_COPY_CLASS(ArgsArray);
 433 };
 434
 435 } // anonymous namespace
 436
 437 // ----------------------------------------------------------------------------
 438 // wxExecute implementations
 439 // ----------------------------------------------------------------------------
 440
 441 #if defined(__DARWIN__)
 442 bool wxMacLaunch(char **argv);
 443 #endif
 444
 445 long wxExecute(const wxString& command, int flags, wxProcess *process)
 446 {
 447     ArgsArray argv(wxCmdLineParser::ConvertStringToArgs(command,
 448                                                         wxCMD_LINE_SPLIT_UNIX));
 449
 450     return wxExecute(argv, flags, process);
 451 }
 452
 453 #if wxUSE_UNICODE
 454
 455 long wxExecute(wchar_t **wargv, int flags, wxProcess *process)
 456 {
 457     ArgsArray argv(wargv);
 458
 459     return wxExecute(argv, flags, process);
 460 }
 461
 462 #endif // wxUSE_UNICODE
 463
 464 // wxExecute: the real worker function
 465 long wxExecute(char **argv, int flags, wxProcess *process)
 466 {
 467     // for the sync execution, we return -1 to indicate failure, but for async
 468     // case we return 0 which is never a valid PID
 469     //
 470     // we define this as a macro, not a variable, to avoid compiler warnings
 471     // about "ERROR_RETURN_CODE value may be clobbered by fork()"
 472     #define ERROR_RETURN_CODE ((flags & wxEXEC_SYNC) ? -1 : 0)
 473
 474     wxCHECK_MSG( *argv, ERROR_RETURN_CODE, wxT("can't exec empty command") );
 475
 476 #if wxUSE_THREADS
 477     // fork() doesn't mix well with POSIX threads: on many systems the program
 478     // deadlocks or crashes for some reason. Probably our code is buggy and
 479     // doesn't do something which must be done to allow this to work, but I
 480     // don't know what yet, so for now just warn the user (this is the least we
 481     // can do) about it
 482     wxASSERT_MSG( wxThread::IsMain(),
 483                     _T("wxExecute() can be called only from the main thread") );
 484 #endif // wxUSE_THREADS
 485
 486 #if defined(__WXCOCOA__) || ( defined(__WXOSX_MAC__) && wxOSX_USE_COCOA_OR_CARBON )
 487     // wxMacLaunch() only executes app bundles and only does it asynchronously.
 488     // It returns false if the target is not an app bundle, thus falling
 489     // through to the regular code for non app bundles.
 490     if ( !(flags & wxEXEC_SYNC) && wxMacLaunch(argv) )
 491     {
 492         // we don't have any PID to return so just make up something non null
 493         return -1;
 494     }
 495 #endif // __DARWIN__
 496
 497
 498     // this struct contains all information which we use for housekeeping
 499     wxExecuteData execData;
 500     execData.flags = flags;
 501     execData.process = process;
 502
 503     // create pipes
 504     if ( !execData.pipeEndProcDetect.Create() )
 505     {
 506         wxLogError( _("Failed to execute '%s'\n"), *argv );
 507
 508         return ERROR_RETURN_CODE;
 509     }
 510
 511     // pipes for inter process communication
 512     wxPipe pipeIn,      // stdin
 513            pipeOut,     // stdout
 514            pipeErr;     // stderr
 515
 516     if ( process && process->IsRedirected() )
 517     {
 518         if ( !pipeIn.Create() || !pipeOut.Create() || !pipeErr.Create() )
 519         {
 520             wxLogError( _("Failed to execute '%s'\n"), *argv );
 521
 522             return ERROR_RETURN_CODE;
 523         }
 524     }
 525
 526     // fork the process
 527     //
 528     // NB: do *not* use vfork() here, it completely breaks this code for some
 529     //     reason under Solaris (and maybe others, although not under Linux)
 530     //     But on OpenVMS we do not have fork so we have to use vfork and
 531     //     cross our fingers that it works.
 532 #ifdef __VMS
 533    pid_t pid = vfork();
 534 #else
 535    pid_t pid = fork();
 536 #endif
 537    if ( pid == -1 )     // error?
 538     {
 539         wxLogSysError( _("Fork failed") );
 540
 541         return ERROR_RETURN_CODE;
 542     }
 543     else if ( pid == 0 )  // we're in child
 544     {
 545         // NB: we used to close all the unused descriptors of the child here
 546         //     but this broke some programs which relied on e.g. FD 1 being
 547         //     always opened so don't do it any more, after all there doesn't
 548         //     seem to be any real problem with keeping them opened
 549
 550 #if !defined(__VMS) && !defined(__EMX__)
 551         if ( flags & wxEXEC_MAKE_GROUP_LEADER )
 552         {
 553             // Set process group to child process' pid.  Then killing -pid
 554             // of the parent will kill the process and all of its children.
 555             setsid();
 556         }
 557 #endif // !__VMS
 558
 559         // reading side can be safely closed but we should keep the write one
 560         // opened, it will be only closed when the process terminates resulting
 561         // in a read notification to the parent
 562         execData.pipeEndProcDetect.Detach(wxPipe::Write);
 563         execData.pipeEndProcDetect.Close();
 564
 565         // redirect stdin, stdout and stderr
 566         if ( pipeIn.IsOk() )
 567         {
 568             if ( dup2(pipeIn[wxPipe::Read], STDIN_FILENO) == -1 ||
 569                  dup2(pipeOut[wxPipe::Write], STDOUT_FILENO) == -1 ||
 570                  dup2(pipeErr[wxPipe::Write], STDERR_FILENO) == -1 )
 571             {
 572                 wxLogSysError(_("Failed to redirect child process input/output"));
 573             }
 574
 575             pipeIn.Close();
 576             pipeOut.Close();
 577             pipeErr.Close();
 578         }
 579
 580         execvp(*argv, argv);
 581
 582         fprintf(stderr, "execvp(");
 583         for ( char **a = argv; *a; a++ )
 584             fprintf(stderr, "%s%s", a == argv ? "" : ", ", *a);
 585         fprintf(stderr, ") failed with error %d!\n", errno);
 586
 587         // there is no return after successful exec()
 588         _exit(-1);
 589
 590         // some compilers complain about missing return - of course, they
 591         // should know that exit() doesn't return but what else can we do if
 592         // they don't?
 593         //
 594         // and, sure enough, other compilers complain about unreachable code
 595         // after exit() call, so we can just always have return here...
 596 #if defined(__VMS) || defined(__INTEL_COMPILER)
 597         return 0;
 598 #endif
 599     }
 600     else // we're in parent
 601     {
 602         // save it for WaitForChild() use
 603         execData.pid = pid;
 604         if (execData.process)
 605             execData.process->SetPid(pid);  // and also in the wxProcess
 606
 607         // prepare for IO redirection
 608
 609 #if HAS_PIPE_INPUT_STREAM
 610         // the input buffer bufOut is connected to stdout, this is why it is
 611         // called bufOut and not bufIn
 612         wxStreamTempInputBuffer bufOut,
 613                                 bufErr;
 614
 615         if ( process && process->IsRedirected() )
 616         {
 617             wxOutputStream *inStream =
 618                 new wxFileOutputStream(pipeIn.Detach(wxPipe::Write));
 619
 620             const int fdOut = pipeOut.Detach(wxPipe::Read);
 621             wxPipeInputStream *outStream = new wxPipeInputStream(fdOut);
 622
 623             const int fdErr = pipeErr.Detach(wxPipe::Read);
 624             wxPipeInputStream *errStream = new wxPipeInputStream(fdErr);
 625
 626             process->SetPipeStreams(outStream, inStream, errStream);
 627
 628             bufOut.Init(outStream);
 629             bufErr.Init(errStream);
 630
 631             execData.bufOut = &bufOut;
 632             execData.bufErr = &bufErr;
 633
 634             execData.fdOut = fdOut;
 635             execData.fdErr = fdErr;
 636         }
 637 #endif // HAS_PIPE_INPUT_STREAM
 638
 639         if ( pipeIn.IsOk() )
 640         {
 641             pipeIn.Close();
 642             pipeOut.Close();
 643             pipeErr.Close();
 644         }
 645
 646         // we want this function to work even if there is no wxApp so ensure
 647         // that we have a valid traits pointer
 648         wxConsoleAppTraits traitsConsole;
 649         wxAppTraits *traits = wxTheApp ? wxTheApp->GetTraits() : NULL;
 650         if ( !traits )
 651             traits = &traitsConsole;
 652
 653         return traits->WaitForChild(execData);
 654     }
 655
 656 #if !defined(__VMS) && !defined(__INTEL_COMPILER)
 657     return ERROR_RETURN_CODE;
 658 #endif
 659 }
 660
 661 #undef ERROR_RETURN_CODE
 662
 663 // ----------------------------------------------------------------------------
 664 // file and directory functions
 665 // ----------------------------------------------------------------------------
 666
 667 const wxChar* wxGetHomeDir( wxString *home  )
 668 {
 669     *home = wxGetUserHome();
 670     wxString tmp;
 671     if ( home->empty() )
 672         *home = wxT("/");
 673 #ifdef __VMS
 674     tmp = *home;
 675     if ( tmp.Last() != wxT(']'))
 676         if ( tmp.Last() != wxT('/')) *home << wxT('/');
 677 #endif
 678     return home->c_str();
 679 }
 680
 681 wxString wxGetUserHome( const wxString &user )
 682 {
 683     struct passwd *who = (struct passwd *) NULL;
 684
 685     if ( !user )
 686     {
 687         wxChar *ptr;
 688
 689         if ((ptr = wxGetenv(wxT("HOME"))) != NULL)
 690         {
 691             return ptr;
 692         }
 693
 694         if ((ptr = wxGetenv(wxT("USER"))) != NULL ||
 695              (ptr = wxGetenv(wxT("LOGNAME"))) != NULL)
 696         {
 697             who = getpwnam(wxSafeConvertWX2MB(ptr));
 698         }
 699
 700         // make sure the user exists!
 701         if ( !who )
 702         {
 703             who = getpwuid(getuid());
 704         }
 705     }
 706     else
 707     {
 708       who = getpwnam (user.mb_str());
 709     }
 710
 711     return wxSafeConvertMB2WX(who ? who->pw_dir : 0);
 712 }
 713
 714 // ----------------------------------------------------------------------------
 715 // network and user id routines
 716 // ----------------------------------------------------------------------------
 717
 718 // private utility function which returns output of the given command, removing
 719 // the trailing newline
 720 static wxString wxGetCommandOutput(const wxString &cmd)
 721 {
 722     FILE *f = popen(cmd.ToAscii(), "r");
 723     if ( !f )
 724     {
 725         wxLogSysError(_T("Executing \"%s\" failed"), cmd.c_str());
 726         return wxEmptyString;
 727     }
 728
 729     wxString s;
 730     char buf[256];
 731     while ( !feof(f) )
 732     {
 733         if ( !fgets(buf, sizeof(buf), f) )
 734             break;
 735
 736         s += wxString::FromAscii(buf);
 737     }
 738
 739     pclose(f);
 740
 741     if ( !s.empty() && s.Last() == _T('\n') )
 742         s.RemoveLast();
 743
 744     return s;
 745 }
 746
 747 // retrieve either the hostname or FQDN depending on platform (caller must
 748 // check whether it's one or the other, this is why this function is for
 749 // private use only)
 750 static bool wxGetHostNameInternal(wxChar *buf, int sz)
 751 {
 752     wxCHECK_MSG( buf, false, wxT("NULL pointer in wxGetHostNameInternal") );
 753
 754     *buf = wxT('\0');
 755
 756     // we're using uname() which is POSIX instead of less standard sysinfo()
 757 #if defined(HAVE_UNAME)
 758     struct utsname uts;
 759     bool ok = uname(&uts) != -1;
 760     if ( ok )
 761     {
 762         wxStrlcpy(buf, wxSafeConvertMB2WX(uts.nodename), sz);
 763     }
 764 #elif defined(HAVE_GETHOSTNAME)
 765     char cbuf[sz];
 766     bool ok = gethostname(cbuf, sz) != -1;
 767     if ( ok )
 768     {
 769         wxStrlcpy(buf, wxSafeConvertMB2WX(cbuf), sz);
 770     }
 771 #else // no uname, no gethostname
 772     wxFAIL_MSG(wxT("don't know host name for this machine"));
 773
 774     bool ok = false;
 775 #endif // uname/gethostname
 776
 777     if ( !ok )
 778     {
 779         wxLogSysError(_("Cannot get the hostname"));
 780     }
 781
 782     return ok;
 783 }
 784
 785 bool wxGetHostName(wxChar *buf, int sz)
 786 {
 787     bool ok = wxGetHostNameInternal(buf, sz);
 788
 789     if ( ok )
 790     {
 791         // BSD systems return the FQDN, we only want the hostname, so extract
 792         // it (we consider that dots are domain separators)
 793         wxChar *dot = wxStrchr(buf, wxT('.'));
 794         if ( dot )
 795         {
 796             // nuke it
 797             *dot = wxT('\0');
 798         }
 799     }
 800
 801     return ok;
 802 }
 803
 804 bool wxGetFullHostName(wxChar *buf, int sz)
 805 {
 806     bool ok = wxGetHostNameInternal(buf, sz);
 807
 808     if ( ok )
 809     {
 810         if ( !wxStrchr(buf, wxT('.')) )
 811         {
 812             struct hostent *host = gethostbyname(wxSafeConvertWX2MB(buf));
 813             if ( !host )
 814             {
 815                 wxLogSysError(_("Cannot get the official hostname"));
 816
 817                 ok = false;
 818             }
 819             else
 820             {
 821                 // the canonical name
 822                 wxStrlcpy(buf, wxSafeConvertMB2WX(host->h_name), sz);
 823             }
 824         }
 825         //else: it's already a FQDN (BSD behaves this way)
 826     }
 827
 828     return ok;
 829 }
 830
 831 bool wxGetUserId(wxChar *buf, int sz)
 832 {
 833     struct passwd *who;
 834
 835     *buf = wxT('\0');
 836     if ((who = getpwuid(getuid ())) != NULL)
 837     {
 838         wxStrlcpy (buf, wxSafeConvertMB2WX(who->pw_name), sz);
 839         return true;
 840     }
 841
 842     return false;
 843 }
 844
 845 bool wxGetUserName(wxChar *buf, int sz)
 846 {
 847 #ifdef HAVE_PW_GECOS
 848     struct passwd *who;
 849
 850     *buf = wxT('\0');
 851     if ((who = getpwuid (getuid ())) != NULL)
 852     {
 853        char *comma = strchr(who->pw_gecos, ',');
 854        if (comma)
 855            *comma = '\0'; // cut off non-name comment fields
 856        wxStrlcpy(buf, wxSafeConvertMB2WX(who->pw_gecos), sz);
 857        return true;
 858     }
 859
 860     return false;
 861 #else // !HAVE_PW_GECOS
 862     return wxGetUserId(buf, sz);
 863 #endif // HAVE_PW_GECOS/!HAVE_PW_GECOS
 864 }
 865
 866 bool wxIsPlatform64Bit()
 867 {
 868     const wxString machine = wxGetCommandOutput(wxT("uname -m"));
 869
 870     // the test for "64" is obviously not 100% reliable but seems to work fine
 871     // in practice
 872     return machine.Contains(wxT("64")) ||
 873                 machine.Contains(wxT("alpha"));
 874 }
 875
 876 // these functions are in src/osx/utilsexc_base.cpp for wxMac
 877 #ifndef __WXMAC__
 878
 879 wxOperatingSystemId wxGetOsVersion(int *verMaj, int *verMin)
 880 {
 881     // get OS version
 882     int major, minor;
 883     wxString release = wxGetCommandOutput(wxT("uname -r"));
 884     if ( release.empty() ||
 885          wxSscanf(release.c_str(), wxT("%d.%d"), &major, &minor) != 2 )
 886     {
 887         // failed to get version string or unrecognized format
 888         major =
 889         minor = -1;
 890     }
 891
 892     if ( verMaj )
 893         *verMaj = major;
 894     if ( verMin )
 895         *verMin = minor;
 896
 897     // try to understand which OS are we running
 898     wxString kernel = wxGetCommandOutput(wxT("uname -s"));
 899     if ( kernel.empty() )
 900         kernel = wxGetCommandOutput(wxT("uname -o"));
 901
 902     if ( kernel.empty() )
 903         return wxOS_UNKNOWN;
 904
 905     return wxPlatformInfo::GetOperatingSystemId(kernel);
 906 }
 907
 908 wxString wxGetOsDescription()
 909 {
 910     return wxGetCommandOutput(wxT("uname -s -r -m"));
 911 }
 912
 913 #endif // !__WXMAC__
 914
 915 unsigned long wxGetProcessId()
 916 {
 917     return (unsigned long)getpid();
 918 }
 919
 920 wxMemorySize wxGetFreeMemory()
 921 {
 922 #if defined(__LINUX__)
 923     // get it from /proc/meminfo
 924     FILE *fp = fopen("/proc/meminfo", "r");
 925     if ( fp )
 926     {
 927         long memFree = -1;
 928
 929         char buf[1024];
 930         if ( fgets(buf, WXSIZEOF(buf), fp) && fgets(buf, WXSIZEOF(buf), fp) )
 931         {
 932             // /proc/meminfo changed its format in kernel 2.6
 933             if ( wxPlatformInfo().CheckOSVersion(2, 6) )
 934             {
 935                 unsigned long cached, buffers;
 936                 sscanf(buf, "MemFree: %ld", &memFree);
 937
 938                 fgets(buf, WXSIZEOF(buf), fp);
 939                 sscanf(buf, "Buffers: %lu", &buffers);
 940
 941                 fgets(buf, WXSIZEOF(buf), fp);
 942                 sscanf(buf, "Cached: %lu", &cached);
 943
 944                 // add to "MemFree" also the "Buffers" and "Cached" values as
 945                 // free(1) does as otherwise the value never makes sense: for
 946                 // kernel 2.6 it's always almost 0
 947                 memFree += buffers + cached;
 948
 949                 // values here are always expressed in kB and we want bytes
 950                 memFree *= 1024;
 951             }
 952             else // Linux 2.4 (or < 2.6, anyhow)
 953             {
 954                 long memTotal, memUsed;
 955                 sscanf(buf, "Mem: %ld %ld %ld", &memTotal, &memUsed, &memFree);
 956             }
 957         }
 958
 959         fclose(fp);
 960
 961         return (wxMemorySize)memFree;
 962     }
 963 #elif defined(__SGI__)
 964     struct rminfo realmem;
 965     if ( sysmp(MP_SAGET, MPSA_RMINFO, &realmem, sizeof realmem) == 0 )
 966         return ((wxMemorySize)realmem.physmem * sysconf(_SC_PAGESIZE));
 967 #elif defined(_SC_AVPHYS_PAGES)
 968     return ((wxMemorySize)sysconf(_SC_AVPHYS_PAGES))*sysconf(_SC_PAGESIZE);
 969 //#elif defined(__FREEBSD__) -- might use sysctl() to find it out, probably
 970 #endif
 971
 972     // can't find it out
 973     return -1;
 974 }
 975
 976 bool wxGetDiskSpace(const wxString& path, wxDiskspaceSize_t *pTotal, wxDiskspaceSize_t *pFree)
 977 {
 978 #if defined(HAVE_STATFS) || defined(HAVE_STATVFS)
 979     // the case to "char *" is needed for AIX 4.3
 980     wxStatfs_t fs;
 981     if ( wxStatfs((char *)(const char*)path.fn_str(), &fs) != 0 )
 982     {
 983         wxLogSysError( wxT("Failed to get file system statistics") );
 984
 985         return false;
 986     }
 987
 988     // under Solaris we also have to use f_frsize field instead of f_bsize
 989     // which is in general a multiple of f_frsize
 990 #ifdef HAVE_STATVFS
 991     wxDiskspaceSize_t blockSize = fs.f_frsize;
 992 #else // HAVE_STATFS
 993     wxDiskspaceSize_t blockSize = fs.f_bsize;
 994 #endif // HAVE_STATVFS/HAVE_STATFS
 995
 996     if ( pTotal )
 997     {
 998         *pTotal = wxDiskspaceSize_t(fs.f_blocks) * blockSize;
 999     }
1000
1001     if ( pFree )
1002     {
1003         *pFree = wxDiskspaceSize_t(fs.f_bavail) * blockSize;
1004     }
1005
1006     return true;
1007 #else // !HAVE_STATFS && !HAVE_STATVFS
1008     return false;
1009 #endif // HAVE_STATFS
1010 }
1011
1012 // ----------------------------------------------------------------------------
1013 // env vars
1014 // ----------------------------------------------------------------------------
1015
1016 #if USE_PUTENV
1017
1018 WX_DECLARE_STRING_HASH_MAP(char *, wxEnvVars);
1019
1020 static wxEnvVars gs_envVars;
1021
1022 class wxSetEnvModule : public wxModule
1023 {
1024 public:
1025     virtual bool OnInit() { return true; }
1026     virtual void OnExit()
1027     {
1028         for ( wxEnvVars::const_iterator i = gs_envVars.begin();
1029               i != gs_envVars.end();
1030               ++i )
1031         {
1032             free(i->second);
1033         }
1034
1035         gs_envVars.clear();
1036     }
1037
1038     DECLARE_DYNAMIC_CLASS(wxSetEnvModule)
1039 };
1040
1041 IMPLEMENT_DYNAMIC_CLASS(wxSetEnvModule, wxModule)
1042
1043 #endif // USE_PUTENV
1044
1045 bool wxGetEnv(const wxString& var, wxString *value)
1046 {
1047     // wxGetenv is defined as getenv()
1048     char *p = wxGetenv(var);
1049     if ( !p )
1050         return false;
1051
1052     if ( value )
1053     {
1054         *value = p;
1055     }
1056
1057     return true;
1058 }
1059
1060 static bool wxDoSetEnv(const wxString& variable, const char *value)
1061 {
1062 #if defined(HAVE_SETENV)
1063     if ( !value )
1064     {
1065 #ifdef HAVE_UNSETENV
1066         // don't test unsetenv() return value: it's void on some systems (at
1067         // least Darwin)
1068         unsetenv(variable.mb_str());
1069         return true;
1070 #else
1071         value = ""; // we can't pass NULL to setenv()
1072 #endif
1073     }
1074
1075     return setenv(variable.mb_str(), value, 1 /* overwrite */) == 0;
1076 #elif defined(HAVE_PUTENV)
1077     wxString s = variable;
1078     if ( value )
1079         s << _T('=') << value;
1080
1081     // transform to ANSI
1082     const wxWX2MBbuf p = s.mb_str();
1083
1084     char *buf = (char *)malloc(strlen(p) + 1);
1085     strcpy(buf, p);
1086
1087     // store the string to free() it later
1088     wxEnvVars::iterator i = gs_envVars.find(variable);
1089     if ( i != gs_envVars.end() )
1090     {
1091         free(i->second);
1092         i->second = buf;
1093     }
1094     else // this variable hadn't been set before
1095     {
1096         gs_envVars[variable] = buf;
1097     }
1098
1099     return putenv(buf) == 0;
1100 #else // no way to set an env var
1101     return false;
1102 #endif
1103 }
1104
1105 bool wxSetEnv(const wxString& variable, const wxString& value)
1106 {
1107     return wxDoSetEnv(variable, value.mb_str());
1108 }
1109
1110 bool wxUnsetEnv(const wxString& variable)
1111 {
1112     return wxDoSetEnv(variable, NULL);
1113 }
1114
1115 // ----------------------------------------------------------------------------
1116 // signal handling
1117 // ----------------------------------------------------------------------------
1118
1119 #if wxUSE_ON_FATAL_EXCEPTION
1120
1121 #include <signal.h>
1122
1123 extern "C" void wxFatalSignalHandler(wxTYPE_SA_HANDLER)
1124 {
1125     if ( wxTheApp )
1126     {
1127         // give the user a chance to do something special about this
1128         wxTheApp->OnFatalException();
1129     }
1130
1131     abort();
1132 }
1133
1134 bool wxHandleFatalExceptions(bool doit)
1135 {
1136     // old sig handlers
1137     static bool s_savedHandlers = false;
1138     static struct sigaction s_handlerFPE,
1139                             s_handlerILL,
1140                             s_handlerBUS,
1141                             s_handlerSEGV;
1142
1143     bool ok = true;
1144     if ( doit && !s_savedHandlers )
1145     {
1146         // install the signal handler
1147         struct sigaction act;
1148
1149         // some systems extend it with non std fields, so zero everything
1150         memset(&act, 0, sizeof(act));
1151
1152         act.sa_handler = wxFatalSignalHandler;
1153         sigemptyset(&act.sa_mask);
1154         act.sa_flags = 0;
1155
1156         ok &= sigaction(SIGFPE, &act, &s_handlerFPE) == 0;
1157         ok &= sigaction(SIGILL, &act, &s_handlerILL) == 0;
1158         ok &= sigaction(SIGBUS, &act, &s_handlerBUS) == 0;
1159         ok &= sigaction(SIGSEGV, &act, &s_handlerSEGV) == 0;
1160         if ( !ok )
1161         {
1162             wxLogDebug(_T("Failed to install our signal handler."));
1163         }
1164
1165         s_savedHandlers = true;
1166     }
1167     else if ( s_savedHandlers )
1168     {
1169         // uninstall the signal handler
1170         ok &= sigaction(SIGFPE, &s_handlerFPE, NULL) == 0;
1171         ok &= sigaction(SIGILL, &s_handlerILL, NULL) == 0;
1172         ok &= sigaction(SIGBUS, &s_handlerBUS, NULL) == 0;
1173         ok &= sigaction(SIGSEGV, &s_handlerSEGV, NULL) == 0;
1174         if ( !ok )
1175         {
1176             wxLogDebug(_T("Failed to uninstall our signal handler."));
1177         }
1178
1179         s_savedHandlers = false;
1180     }
1181     //else: nothing to do
1182
1183     return ok;
1184 }
1185
1186 #endif // wxUSE_ON_FATAL_EXCEPTION
1187
1188 // ----------------------------------------------------------------------------
1189 // wxExecute support
1190 // ----------------------------------------------------------------------------
1191
1192 int wxAppTraits::AddProcessCallback(wxEndProcessData *data, int fd)
1193 {
1194     // define a custom handler processing only the closure of the descriptor
1195     struct wxEndProcessFDIOHandler : public wxFDIOHandler
1196     {
1197         wxEndProcessFDIOHandler(wxEndProcessData *data, int fd)
1198             : m_data(data), m_fd(fd)
1199         {
1200         }
1201
1202         virtual void OnReadWaiting()
1203         {
1204             wxFDIODispatcher::Get()->UnregisterFD(m_fd);
1205             close(m_fd);
1206
1207             wxHandleProcessTermination(m_data);
1208
1209             delete this;
1210         }
1211
1212         virtual void OnWriteWaiting() { wxFAIL_MSG("unreachable"); }
1213         virtual void OnExceptionWaiting() { wxFAIL_MSG("unreachable"); }
1214
1215         wxEndProcessData * const m_data;
1216         const int m_fd;
1217     };
1218
1219     wxFDIODispatcher::Get()->RegisterFD
1220                              (
1221                                  fd,
1222                                  new wxEndProcessFDIOHandler(data, fd),
1223                                  wxFDIO_INPUT
1224                              );
1225     return fd; // unused, but return something unique for the tag
1226 }
1227
1228 bool wxAppTraits::CheckForRedirectedIO(wxExecuteData& execData)
1229 {
1230 #if HAS_PIPE_INPUT_STREAM
1231     bool hasIO = false;
1232
1233     if ( execData.bufOut && execData.bufOut->Update() )
1234         hasIO = true;
1235
1236     if ( execData.bufErr && execData.bufErr->Update() )
1237         hasIO = true;
1238
1239     return hasIO;
1240 #else // !HAS_PIPE_INPUT_STREAM
1241     return false;
1242 #endif // HAS_PIPE_INPUT_STREAM/!HAS_PIPE_INPUT_STREAM
1243 }
1244
1245 // helper classes/functions used by WaitForChild()
1246 namespace
1247 {
1248
1249 // convenient base class for IO handlers which are registered for read
1250 // notifications only and which also stores the FD we're reading from
1251 //
1252 // the derived classes still have to implement OnReadWaiting()
1253 class wxReadFDIOHandler : public wxFDIOHandler
1254 {
1255 public:
1256     wxReadFDIOHandler(wxFDIODispatcher& disp, int fd) : m_fd(fd)
1257     {
1258         if ( fd )
1259             disp.RegisterFD(fd, this, wxFDIO_INPUT);
1260     }
1261
1262     virtual void OnWriteWaiting() { wxFAIL_MSG("unreachable"); }
1263     virtual void OnExceptionWaiting() { wxFAIL_MSG("unreachable"); }
1264
1265 protected:
1266     const int m_fd;
1267
1268     wxDECLARE_NO_COPY_CLASS(wxReadFDIOHandler);
1269 };
1270
1271 // class for monitoring our end of the process detection pipe, simply sets a
1272 // flag when input on the pipe (which must be due to EOF) is detected
1273 class wxEndHandler : public wxReadFDIOHandler
1274 {
1275 public:
1276     wxEndHandler(wxFDIODispatcher& disp, int fd)
1277         : wxReadFDIOHandler(disp, fd)
1278     {
1279         m_terminated = false;
1280     }
1281
1282     bool Terminated() const { return m_terminated; }
1283
1284     virtual void OnReadWaiting() { m_terminated = true; }
1285
1286 private:
1287     bool m_terminated;
1288
1289     wxDECLARE_NO_COPY_CLASS(wxEndHandler);
1290 };
1291
1292 #if HAS_PIPE_INPUT_STREAM
1293
1294 // class for monitoring our ends of child stdout/err, should be constructed
1295 // with the FD and stream from wxExecuteData and will do nothing if they're
1296 // invalid
1297 //
1298 // unlike wxEndHandler this class registers itself with the provided dispatcher
1299 class wxRedirectedIOHandler : public wxReadFDIOHandler
1300 {
1301 public:
1302     wxRedirectedIOHandler(wxFDIODispatcher& disp,
1303                           int fd,
1304                           wxStreamTempInputBuffer *buf)
1305         : wxReadFDIOHandler(disp, fd),
1306           m_buf(buf)
1307     {
1308     }
1309
1310     virtual void OnReadWaiting()
1311     {
1312         m_buf->Update();
1313     }
1314
1315 private:
1316     wxStreamTempInputBuffer * const m_buf;
1317
1318     wxDECLARE_NO_COPY_CLASS(wxRedirectedIOHandler);
1319 };
1320
1321 #endif // HAS_PIPE_INPUT_STREAM
1322
1323 // helper function which calls waitpid() and analyzes the result
1324 int DoWaitForChild(int pid, int flags = 0)
1325 {
1326     wxASSERT_MSG( pid > 0, "invalid PID" );
1327
1328     int status, rc;
1329
1330     // loop while we're getting EINTR
1331     for ( ;; )
1332     {
1333         rc = waitpid(pid, &status, flags);
1334
1335         if ( rc != -1 || errno != EINTR )
1336             break;
1337     }
1338
1339     if ( rc == 0 )
1340     {
1341         // This can only happen if the child application closes our dummy pipe
1342         // that is used to monitor its lifetime; in that case, our best bet is
1343         // to pretend the process did terminate, because otherwise wxExecute()
1344         // would hang indefinitely (OnReadWaiting() won't be called again, the
1345         // descriptor is closed now).
1346         wxLogDebug("Child process (PID %d) still alive but pipe closed so "
1347                    "generating a close notification", pid);
1348     }
1349     else if ( rc == -1 )
1350     {
1351         wxLogLastError(wxString::Format("waitpid(%d)", pid));
1352     }
1353     else // child did terminate
1354     {
1355         wxASSERT_MSG( rc == pid, "unexpected waitpid() return value" );
1356
1357         if ( WIFEXITED(status) )
1358             return WEXITSTATUS(status);
1359         else if ( WIFSIGNALED(status) )
1360             return -WTERMSIG(status);
1361         else
1362         {
1363             wxLogError("Child process (PID %d) exited for unknown reason, "
1364                        "status = %d", pid, status);
1365         }
1366     }
1367
1368     return -1;
1369 }
1370
1371 } // anonymous namespace
1372
1373 int wxAppTraits::WaitForChild(wxExecuteData& execData)
1374 {
1375     if ( !(execData.flags & wxEXEC_SYNC) )
1376     {
1377         // asynchronous execution: just launch the process and return,
1378         // endProcData will be destroyed when it terminates (currently we leak
1379         // it if the process doesn't terminate before we do and this should be
1380         // fixed but it's not a real leak so it's not really very high
1381         // priority)
1382         wxEndProcessData *endProcData = new wxEndProcessData;
1383         endProcData->process = execData.process;
1384         endProcData->pid = execData.pid;
1385         endProcData->tag = AddProcessCallback
1386                            (
1387                              endProcData,
1388                              execData.GetEndProcReadFD()
1389                            );
1390         endProcData->async = true;
1391
1392         return execData.pid;
1393     }
1394     //else: synchronous execution case
1395
1396 #if HAS_PIPE_INPUT_STREAM
1397     wxProcess * const process = execData.process;
1398     if ( process && process->IsRedirected() )
1399     {
1400         // we can't simply block waiting for the child to terminate as we would
1401         // dead lock if it writes more than the pipe buffer size (typically
1402         // 4KB) bytes of output -- it would then block waiting for us to read
1403         // the data while we'd block waiting for it to terminate
1404         //
1405         // so multiplex here waiting for any input from the child or closure of
1406         // the pipe used to indicate its termination
1407         wxSelectDispatcher disp;
1408
1409         wxEndHandler endHandler(disp, execData.GetEndProcReadFD());
1410
1411         wxRedirectedIOHandler outHandler(disp, execData.fdOut, execData.bufOut),
1412                               errHandler(disp, execData.fdErr, execData.bufErr);
1413
1414         while ( !endHandler.Terminated() )
1415         {
1416             disp.Dispatch();
1417         }
1418     }
1419     //else: no IO redirection, just block waiting for the child to exit
1420 #endif // HAS_PIPE_INPUT_STREAM
1421
1422     return DoWaitForChild(execData.pid);
1423 }
1424
1425 void wxHandleProcessTermination(wxEndProcessData *data)
1426 {
1427     data->exitcode = DoWaitForChild(data->pid, WNOHANG);
1428
1429     // notify user about termination if required
1430     if ( data->process )
1431     {
1432         data->process->OnTerminate(data->pid, data->exitcode);
1433     }
1434
1435     if ( data->async )
1436     {
1437         // in case of asynchronous execution we don't need this data any more
1438         // after the child terminates
1439         delete data;
1440     }
1441     else // sync execution
1442     {
1443         // let wxExecute() know that the process has terminated
1444         data->pid = 0;
1445     }
1446 }
1447