int wxGUIAppTraits::WaitForChild(wxExecuteData& execData)
{
wxEndProcessData *endProcData = new wxEndProcessData;
const int flags = execData.flags;
// wxAddProcessCallback is now (with DARWIN) allowed to call the
// callback function directly if the process terminates before
// the callback can be added to the run loop. Set up the endProcData.
if ( flags & wxEXEC_SYNC )
{
// we may have process for capturing the program output, but it's
// not used in wxEndProcessData in the case of sync execution
endProcData->process = NULL;
// sync execution: indicate it by negating the pid
endProcData->pid = -execData.pid;
}
else
{
// async execution, nothing special to do -- caller will be
// notified about the process termination if process != NULL, endProcData
// will be deleted in GTK_EndProcessDetector
endProcData->process = execData.process;
endProcData->pid = execData.pid;
}
#if defined(__DARWIN__) && (defined(__WXMAC__) || defined(__WXCOCOA__))
endProcData->tag = wxAddProcessCallbackForPid(endProcData, execData.pid);
#else
endProcData->tag = wxAddProcessCallback
(
endProcData,
execData.pipeEndProcDetect.Detach(wxPipe::Read)
);
execData.pipeEndProcDetect.Close();
#endif // defined(__DARWIN__) && (defined(__WXMAC__) || defined(__WXCOCOA__))
if ( flags & wxEXEC_SYNC )
{
wxBusyCursor bc;
wxWindowDisabler *wd = flags & wxEXEC_NODISABLE ? NULL
: new wxWindowDisabler;
// endProcData->pid will be set to 0 from GTK_EndProcessDetector when the
// process terminates
while ( endProcData->pid != 0 )
{
bool idle = true;
#if wxUSE_STREAMS
if ( execData.bufOut )
{
execData.bufOut->Update();
idle = false;
}
if ( execData.bufErr )
{
execData.bufErr->Update();
idle = false;
}
#endif // wxUSE_STREAMS
// don't consume 100% of the CPU while we're sitting in this
// loop
if ( idle )
wxMilliSleep(1);
// give GTK+ a chance to call GTK_EndProcessDetector here and
// also repaint the GUI
wxYield();
}
int exitcode = endProcData->exitcode;
delete wd;
delete endProcData;
return exitcode;
}
else // async execution
{
return execData.pid;
}
}
long wxExecute(wxChar **argv,
int flags,
wxProcess *process)
{
// for the sync execution, we return -1 to indicate failure, but for async
// case we return 0 which is never a valid PID
//
// we define this as a macro, not a variable, to avoid compiler warnings
// about "ERROR_RETURN_CODE value may be clobbered by fork()"
#define ERROR_RETURN_CODE ((flags & wxEXEC_SYNC) ? -1 : 0)
wxCHECK_MSG( *argv, ERROR_RETURN_CODE, wxT("can't exec empty command") );
#if wxUSE_UNICODE
int mb_argc = 0;
char *mb_argv[WXEXECUTE_NARGS];
while (argv[mb_argc])
{
wxWX2MBbuf mb_arg = wxConvertWX2MB(argv[mb_argc]);
mb_argv[mb_argc] = strdup(mb_arg);
mb_argc++;
}
mb_argv[mb_argc] = (char *) NULL;
// this macro will free memory we used above
#define ARGS_CLEANUP \
for ( mb_argc = 0; mb_argv[mb_argc]; mb_argc++ ) \
free(mb_argv[mb_argc])
#else // ANSI
// no need for cleanup
#define ARGS_CLEANUP
wxChar **mb_argv = argv;
#endif // Unicode/ANSI
#if wxUSE_GUI && !defined(__DARWIN__)
// create pipes
wxPipe pipeEndProcDetect;
if ( !pipeEndProcDetect.Create() )
{
wxLogError( _("Failed to execute '%s'\n"), *argv );
ARGS_CLEANUP;
return ERROR_RETURN_CODE;
}
#endif // wxUSE_GUI && !defined(__DARWIN__)
// pipes for inter process communication
wxPipe pipeIn, // stdin
pipeOut, // stdout
pipeErr; // stderr
if ( process && process->IsRedirected() )
{
if ( !pipeIn.Create() || !pipeOut.Create() || !pipeErr.Create() )
{
wxLogError( _("Failed to execute '%s'\n"), *argv );
ARGS_CLEANUP;
return ERROR_RETURN_CODE;
}
}
// fork the process
//
// NB: do *not* use vfork() here, it completely breaks this code for some
// reason under Solaris (and maybe others, although not under Linux)
// But on OpenVMS we do not have fork so we have to use vfork and
// cross our fingers that it works.
#ifdef __VMS
pid_t pid = vfork();
#else
pid_t pid = fork();
#endif
if ( pid == -1 ) // error?
{
wxLogSysError( _("Fork failed") );
ARGS_CLEANUP;
return ERROR_RETURN_CODE;
}
else if ( pid == 0 ) // we're in child
{
// These lines close the open file descriptors to to avoid any
// input/output which might block the process or irritate the user. If
// one wants proper IO for the subprocess, the right thing to do is to
// start an xterm executing it.
if ( !(flags & wxEXEC_SYNC) )
{
for ( int fd = 0; fd < FD_SETSIZE; fd++ )
{
if ( fd == pipeIn[wxPipe::Read]
|| fd == pipeOut[wxPipe::Write]
|| fd == pipeErr[wxPipe::Write]
#if wxUSE_GUI && !defined(__DARWIN__)
|| fd == pipeEndProcDetect[wxPipe::Write]
#endif // wxUSE_GUI && !defined(__DARWIN__)
)
{
// don't close this one, we still need it
continue;
}
// leave stderr opened too, it won't do any harm
if ( fd != STDERR_FILENO )
close(fd);
}
}
#if !defined(__VMS) && !defined(__EMX__)
if ( flags & wxEXEC_MAKE_GROUP_LEADER )
{
// Set process group to child process' pid. Then killing -pid
// of the parent will kill the process and all of its children.
setsid();
}
#endif // !__VMS
#if wxUSE_GUI && !defined(__DARWIN__)
// reading side can be safely closed but we should keep the write one
// opened
pipeEndProcDetect.Detach(wxPipe::Write);
pipeEndProcDetect.Close();
#endif // wxUSE_GUI && !defined(__DARWIN__)
// redirect stdin, stdout and stderr
if ( pipeIn.IsOk() )
{
if ( dup2(pipeIn[wxPipe::Read], STDIN_FILENO) == -1 ||
dup2(pipeOut[wxPipe::Write], STDOUT_FILENO) == -1 ||
dup2(pipeErr[wxPipe::Write], STDERR_FILENO) == -1 )
{
wxLogSysError(_("Failed to redirect child process input/output"));
}
pipeIn.Close();
pipeOut.Close();
pipeErr.Close();
}
execvp (*mb_argv, mb_argv);
fprintf(stderr, "execvp(");
for ( char **ppc = mb_argv; *ppc; ppc++ )
fprintf(stderr, "%s%s", ppc == mb_argv ? "" : ", ", *ppc);
fprintf(stderr, ") failed with error %d!\n", errno);
// there is no return after successful exec()
_exit(-1);
// some compilers complain about missing return - of course, they
// should know that exit() doesn't return but what else can we do if
// they don't?
//
// and, sure enough, other compilers complain about unreachable code
// after exit() call, so we can just always have return here...
#if defined(__VMS) || defined(__INTEL_COMPILER)
return 0;
#endif
}
else // we're in parent
{
ARGS_CLEANUP;
// prepare for IO redirection
#if wxUSE_STREAMS
// the input buffer bufOut is connected to stdout, this is why it is
// called bufOut and not bufIn
wxStreamTempInputBuffer bufOut,
bufErr;
#endif // wxUSE_STREAMS
if ( process && process->IsRedirected() )
{
#if wxUSE_STREAMS
wxOutputStream *inStream =
new wxFileOutputStream(pipeIn.Detach(wxPipe::Write));
wxPipeInputStream *outStream =
new wxPipeInputStream(pipeOut.Detach(wxPipe::Read));
wxPipeInputStream *errStream =
new wxPipeInputStream(pipeErr.Detach(wxPipe::Read));
process->SetPipeStreams(outStream, inStream, errStream);
bufOut.Init(outStream);
bufErr.Init(errStream);
#endif // wxUSE_STREAMS
}
if ( pipeIn.IsOk() )
{
pipeIn.Close();
pipeOut.Close();
pipeErr.Close();
}
#if wxUSE_GUI && !defined(__WXMICROWIN__)
wxEndProcessData *data = new wxEndProcessData;
// wxAddProcessCallback is now (with DARWIN) allowed to call the
// callback function directly if the process terminates before
// the callback can be added to the run loop. Set up the data.
if ( flags & wxEXEC_SYNC )
{
// we may have process for capturing the program output, but it's
// not used in wxEndProcessData in the case of sync execution
data->process = NULL;
// sync execution: indicate it by negating the pid
data->pid = -pid;
}
else
{
// async execution, nothing special to do - caller will be
// notified about the process termination if process != NULL, data
// will be deleted in GTK_EndProcessDetector
data->process = process;
data->pid = pid;
}
#if defined(__DARWIN__)
data->tag = wxAddProcessCallbackForPid(data,pid);
#else
data->tag = wxAddProcessCallback
(
data,
pipeEndProcDetect.Detach(wxPipe::Read)
);
pipeEndProcDetect.Close();
#endif // defined(__DARWIN__)
if ( flags & wxEXEC_SYNC )
{
wxBusyCursor bc;
wxWindowDisabler wd;
// data->pid will be set to 0 from GTK_EndProcessDetector when the
// process terminates
while ( data->pid != 0 )
{
#if wxUSE_STREAMS
bufOut.Update();
bufErr.Update();
#endif // wxUSE_STREAMS
// give GTK+ a chance to call GTK_EndProcessDetector here and
// also repaint the GUI
wxYield();
}
int exitcode = data->exitcode;
delete data;
return exitcode;
}
else // async execution
{
return pid;
}
#else // !wxUSE_GUI
wxASSERT_MSG( flags & wxEXEC_SYNC,
wxT("async execution not supported yet") );
int exitcode = 0;
if ( waitpid(pid, &exitcode, 0) == -1 || !WIFEXITED(exitcode) )
{
wxLogSysError(_("Waiting for subprocess termination failed"));
}
return exitcode;
#endif // wxUSE_GUI
}
return ERROR_RETURN_CODE;
}
