src/support/Systemcall.cpp

   1 /**
   2  * \file Systemcall.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Asger Alstrup
   7  * \author Angus Leeming
   8  * \author Enrico Forestieri
   9  * \author Peter Kuemmel
  10  *
  11  * Full author contact details are available in file CREDITS.
  12  */
  13
  14 #include <config.h>
  15
  16 #include "support/debug.h"
  17 #include "support/lstrings.h"
  18 #include "support/qstring_helpers.h"
  19 #include "support/Systemcall.h"
  20 #include "support/SystemcallPrivate.h"
  21 #include "support/os.h"
  22
  23
  24 #include <cstdlib>
  25 #include <iostream>
  26
  27 #include <QProcess>
  28 #include <QTime>
  29 #include <QThread>
  30 #include <QCoreApplication>
  31 #include <QDebug>
  32
  33 #define USE_QPROCESS
  34
  35
  36 struct Sleep : QThread
  37 {
  38         static void millisec(unsigned long ms)
  39         {
  40                 QThread::usleep(ms * 1000);
  41         }
  42 };
  43
  44
  45
  46 using namespace std;
  47
  48 namespace lyx {
  49 namespace support {
  50
  51
  52
  53 // Reuse of instance
  54 #ifndef USE_QPROCESS
  55 int Systemcall::startscript(Starttype how, string const & what)
  56 {
  57         string command = what;
  58
  59         if (how == DontWait) {
  60                 switch (os::shell()) {
  61                 case os::UNIX:
  62                         command += " &";
  63                         break;
  64                 case os::CMD_EXE:
  65                         command = "start /min " + command;
  66                         break;
  67                 }
  68         }
  69
  70         return ::system(command.c_str());
  71 }
  72
  73 #else
  74
  75 namespace {
  76
  77 string const parsecmd(string const & cmd, string & outfile)
  78 {
  79         bool inquote = false;
  80         bool escaped = false;
  81
  82         for (size_t i = 0; i < cmd.length(); ++i) {
  83                 char c = cmd[i];
  84                 if (c == '"' && !escaped)
  85                         inquote = !inquote;
  86                 else if (c == '\\' && !escaped)
  87                         escaped = !escaped;
  88                 else if (c == '>' && !(inquote || escaped)) {
  89                         outfile = trim(cmd.substr(i + 1), " \"");
  90                         return trim(cmd.substr(0, i));
  91                 } else
  92                         escaped = false;
  93         }
  94         outfile.erase();
  95         return cmd;
  96 }
  97
  98 } // namespace anon
  99
 100
 101
 102 int Systemcall::startscript(Starttype how, string const & what, bool process_events)
 103 {
 104         string outfile;
 105         QString cmd = toqstr(parsecmd(what, outfile));
 106         SystemcallPrivate d(outfile);
 107
 108
 109         d.startProcess(cmd);
 110   if (!d.waitWhile(SystemcallPrivate::Starting, process_events, -1)) {
 111                 LYXERR0("QProcess " << cmd << " did not start!");
 112                 LYXERR0("error " << d.errorMessage());
 113                 return 10;
 114         }
 115
 116         if (how == DontWait) {
 117                 QProcess* released = d.releaseProcess();
 118                 (void) released; // TODO who deletes it?
 119                 return 0;
 120         }
 121
 122         if (!d.waitWhile(SystemcallPrivate::Running, process_events, 180000)) {
 123                 LYXERR0("QProcess " << cmd << " did not finished!");
 124                 LYXERR0("error " << d.errorMessage());
 125                 LYXERR0("status " << d.exitStatusMessage());
 126                 return 20;
 127         }
 128
 129         int const exit_code = d.exitCode();
 130         if (exit_code) {
 131     LYXERR0("QProcess cmd: ' " << cmd << "' finished with exit code " << exit_code);
 132         }
 133
 134         return exit_code;
 135 }
 136
 137
 138 SystemcallPrivate::SystemcallPrivate(const std::string& of) :
 139                                 proc_(new QProcess), outindex_(0), errindex_(0),
 140                                 outfile(of), showout_(false), showerr_(false), process_events(false)
 141 {
 142         if (!outfile.empty()) {
 143                 // Check whether we have to simply throw away the output.
 144                 if (outfile != os::nulldev())
 145                         proc_->setStandardOutputFile(toqstr(outfile));
 146         } else if (os::is_terminal(os::STDOUT))
 147                 showout();
 148         if (os::is_terminal(os::STDERR))
 149                 showerr();
 150
 151         connect(proc_, SIGNAL(readyReadStandardOutput()), SLOT(stdOut()));
 152         connect(proc_, SIGNAL(readyReadStandardError()), SLOT(stdErr()));
 153         connect(proc_, SIGNAL(error(QProcess::ProcessError)), SLOT(processError(QProcess::ProcessError)));
 154         connect(proc_, SIGNAL(started()), this, SLOT(processStarted()));
 155         connect(proc_, SIGNAL(finished(int, QProcess::ExitStatus)), SLOT(processFinished(int, QProcess::ExitStatus)));
 156 }
 157
 158
 159
 160 void SystemcallPrivate::startProcess(const QString& cmd)
 161 {
 162         if (proc_) {
 163                 state = SystemcallPrivate::Starting;
 164                 proc_->start(cmd);
 165         }
 166 }
 167
 168
 169 void SystemcallPrivate::processEvents()
 170 {
 171         if(process_events) {
 172                 //static int count = 0; qDebug() << count++ << ": waitAndProcessEvents";
 173                 QCoreApplication::processEvents(QEventLoop::AllEvents);
 174         }
 175 }
 176
 177
 178 void SystemcallPrivate::waitAndProcessEvents()
 179 {
 180         Sleep::millisec(100);
 181         processEvents();
 182 }
 183
 184
 185 bool SystemcallPrivate::waitWhile(State waitwhile, bool proc_events, int timeout)
 186 {
 187         if (!proc_)
 188                 return false;
 189
 190         process_events = proc_events;
 191
 192         // Block GUI while waiting,
 193         // relay on QProcess' wait functions
 194         if (!process_events) {
 195                 if (waitwhile == Starting)
 196                         return proc_->waitForStarted(timeout);
 197                 if (waitwhile == Running)
 198                         return proc_->waitForFinished(timeout);
 199                 return false;
 200         }
 201
 202         // process events while waiting, no timeout
 203         if (timeout == -1) {
 204                 while (state == waitwhile && state != Error) {
 205                         waitAndProcessEvents();
 206                 }
 207                 return state != Error;
 208         }
 209
 210         // process events while waiting whith timeout
 211         QTime timer;
 212         timer.start();
 213         while (state == waitwhile && state != Error && timer.elapsed() < timeout) {
 214                 waitAndProcessEvents();
 215         }
 216         return (state != Error) && (timer.elapsed() < timeout);
 217 }
 218
 219
 220 SystemcallPrivate::~SystemcallPrivate()
 221 {
 222         flush();
 223
 224         if (outindex_) {
 225                 outdata_[outindex_] = '\0';
 226                 outindex_ = 0;
 227                 cout << outdata_;
 228         }
 229         cout.flush();
 230         if (errindex_) {
 231                 errdata_[errindex_] = '\0';
 232                 errindex_ = 0;
 233                 cerr << errdata_;
 234         }
 235         cerr.flush();
 236
 237         killProcess();
 238 }
 239
 240
 241 void SystemcallPrivate::flush()
 242 {
 243         if (proc_) {
 244                 // If the output has been redirected, we write it all at once.
 245                 // Even if we are not running in a terminal, the output could go
 246                 // to some log file, for example ~/.xsession-errors on *nix.
 247                 if (!os::is_terminal(os::STDOUT) && outfile.empty())
 248                         cout << fromqstr(QString::fromLocal8Bit(
 249                                                 proc_->readAllStandardOutput().data()));
 250                 if (!os::is_terminal(os::STDERR))
 251                         cerr << fromqstr(QString::fromLocal8Bit(
 252                                                 proc_->readAllStandardError().data()));
 253         }
 254 }
 255
 256
 257 void SystemcallPrivate::stdOut()
 258 {
 259         if (proc_ && showout_) {
 260                 char c;
 261                 proc_->setReadChannel(QProcess::StandardOutput);
 262                 while (proc_->getChar(&c)) {
 263                         outdata_[outindex_++] = c;
 264                         if (c == '\n' || outindex_ + 1 == bufsize_) {
 265                                 outdata_[outindex_] = '\0';
 266                                 outindex_ = 0;
 267                                 cout << outdata_;
 268                         }
 269                 }
 270         }
 271         processEvents();
 272 }
 273
 274
 275 void SystemcallPrivate::stdErr()
 276 {
 277         if (proc_ && showerr_) {
 278                 char c;
 279                 proc_->setReadChannel(QProcess::StandardError);
 280                 while (proc_->getChar(&c)) {
 281                         errdata_[errindex_++] = c;
 282                         if (c == '\n' || errindex_ + 1 == bufsize_) {
 283                                 errdata_[errindex_] = '\0';
 284                                 errindex_ = 0;
 285                                 cerr << errdata_;
 286                         }
 287                 }
 288         }
 289         processEvents();
 290 }
 291
 292
 293 void SystemcallPrivate::processStarted()
 294 {
 295         state = Running;
 296         // why do we get two started signals?
 297         //disconnect(proc_, SIGNAL(started()), this, SLOT(processStarted()));
 298 }
 299
 300
 301 void SystemcallPrivate::processFinished(int, QProcess::ExitStatus)
 302 {
 303         state = Finished;
 304 }
 305
 306
 307 void SystemcallPrivate::processError(QProcess::ProcessError)
 308 {
 309         state = Error;
 310 }
 311
 312
 313 QString SystemcallPrivate::errorMessage() const
 314 {
 315         if (!proc_)
 316                 return "No QProcess available";
 317
 318         QString message;
 319         switch (proc_->error()) {
 320                 case QProcess::FailedToStart:
 321                         message = "The process failed to start. Either the invoked program is missing, "
 322                                       "or you may have insufficient permissions to invoke the program.";
 323                         break;
 324                 case QProcess::Crashed:
 325                         message = "The process crashed some time after starting successfully.";
 326                         break;
 327                 case QProcess::Timedout:
 328                         message = "The process timed out. It might be restarted automatically.";
 329                         break;
 330                 case QProcess::WriteError:
 331                         message = "An error occurred when attempting to write to the process-> For example, "
 332                                       "the process may not be running, or it may have closed its input channel.";
 333                         break;
 334                 case QProcess::ReadError:
 335                         message = "An error occurred when attempting to read from the process-> For example, "
 336                                       "the process may not be running.";
 337                         break;
 338                 case QProcess::UnknownError:
 339                 default:
 340                         message = "An unknown error occured.";
 341                         break;
 342         }
 343         return message;
 344 }
 345
 346
 347 QString SystemcallPrivate::exitStatusMessage() const
 348 {
 349         if (!proc_)
 350                 return "No QProcess available";
 351
 352         QString message;
 353         switch (proc_->exitStatus()) {
 354                 case QProcess::NormalExit:
 355                         message = "The process exited normally.";
 356                         break;
 357                 case QProcess::CrashExit:
 358                         message = "The process crashed.";
 359                         break;
 360                 default:
 361                         message = "Unknown exit state.";
 362                         break;
 363         }
 364         return message;
 365 }
 366
 367
 368 int SystemcallPrivate::exitCode()
 369 {
 370         if (!proc_)
 371                 return -1;
 372
 373         return proc_->exitCode();
 374 }
 375
 376
 377 QProcess* SystemcallPrivate::releaseProcess()
 378 {
 379         QProcess* released = proc_;
 380         proc_ = 0;
 381         return released;
 382 }
 383
 384
 385 void SystemcallPrivate::killProcess()
 386 {
 387         killProcess(proc_);
 388 }
 389
 390
 391 void SystemcallPrivate::killProcess(QProcess * p)
 392 {
 393         if (p) {
 394                 p->disconnect();
 395                 p->closeReadChannel(QProcess::StandardOutput);
 396                 p->closeReadChannel(QProcess::StandardError);
 397                 p->close();
 398                 delete p;
 399         }
 400 }
 401
 402
 403
 404 #include "moc_SystemcallPrivate.cpp"
 405 #endif
 406
 407 } // namespace support
 408 } // namespace lyx