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