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
  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)
 103 {
 104         string outfile;
 105         QString cmd = toqstr(parsecmd(what, outfile));
 106         SystemcallPrivate d(outfile);
 107
 108         bool process_events = false;
 109
 110         d.startProcess(cmd);
 111         if (!d.waitWhile(SystemcallPrivate::Starting, process_events, 3000)) {
 112                 LYXERR0("QProcess " << 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("QProcess " << 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("QProcess " << cmd << " finished!");
 133                 LYXERR0("error " << exit_code << ": " << d.errorMessage());
 134         }
 135
 136         return exit_code;
 137 }
 138
 139
 140 SystemcallPrivate::SystemcallPrivate(const std::string& of) :
 141                                 proc_(new QProcess), outindex_(0),
 142                                 errindex_(0), showout_(false), showerr_(false), outfile(of)
 143 {
 144         if (!outfile.empty()) {
 145                 // Check whether we have to simply throw away the output.
 146                 if (outfile != os::nulldev())
 147                         proc_->setStandardOutputFile(toqstr(outfile));
 148         } else if (os::is_terminal(os::STDOUT))
 149                 showout();
 150         if (os::is_terminal(os::STDERR))
 151                 showerr();
 152
 153         connect(proc_, SIGNAL(readyReadStandardOutput()), SLOT(stdOut()));
 154         connect(proc_, SIGNAL(readyReadStandardError()), SLOT(stdErr()));
 155         connect(proc_, SIGNAL(error(QProcess::ProcessError)), SLOT(processError(QProcess::ProcessError)));
 156         connect(proc_, SIGNAL(started()), this, SLOT(processStarted()));
 157         connect(proc_, SIGNAL(finished(int, QProcess::ExitStatus)), SLOT(processFinished(int, QProcess::ExitStatus)));
 158 }
 159
 160
 161
 162 void SystemcallPrivate::startProcess(const QString& cmd)
 163 {
 164         if (proc_) {
 165                 state = SystemcallPrivate::Starting;
 166                 proc_->start(cmd);
 167         }
 168 }
 169
 170
 171 void SystemcallPrivate::waitAndProcessEvents()
 172 {
 173         Sleep::millisec(100);
 174         QCoreApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
 175 }
 176
 177
 178 bool SystemcallPrivate::waitWhile(State waitwhile, bool process_events, int timeout)
 179 {
 180         if (!proc_)
 181                 return false;
 182
 183         // Block GUI while waiting,
 184         // relay on QProcess' wait functions
 185         if (!process_events) {
 186                 if (waitwhile == Starting)
 187                         return proc_->waitForStarted(timeout);
 188                 if (waitwhile == Running)
 189                         return proc_->waitForFinished(timeout);
 190                 return false;
 191         }
 192
 193         // process events while waiting, no timeout
 194         if (timeout == -1) {
 195                 while (state == waitwhile && state != Error) {
 196                         waitAndProcessEvents();
 197                 }
 198                 return state != Error;
 199         }
 200
 201         // process events while waiting whith timeout
 202         QTime timer;
 203         timer.start();
 204         while (state == waitwhile && state != Error && timer.elapsed() < timeout) {
 205                 waitAndProcessEvents();
 206         }
 207         return (state != Error) && (timer.elapsed() < timeout);
 208 }
 209
 210
 211
 212 SystemcallPrivate::~SystemcallPrivate()
 213 {
 214         flush();
 215
 216         if (outindex_) {
 217                 outdata_[outindex_] = '\0';
 218                 outindex_ = 0;
 219                 cout << outdata_;
 220         }
 221         cout.flush();
 222         if (errindex_) {
 223                 errdata_[errindex_] = '\0';
 224                 errindex_ = 0;
 225                 cerr << errdata_;
 226         }
 227         cerr.flush();
 228
 229         killProcess();
 230 }
 231
 232
 233 void SystemcallPrivate::flush()
 234 {
 235         if (proc_) {
 236                 // If the output has been redirected, we write it all at once.
 237                 // Even if we are not running in a terminal, the output could go
 238                 // to some log file, for example ~/.xsession-errors on *nix.
 239                 if (!os::is_terminal(os::STDOUT) && outfile.empty())
 240                         cout << fromqstr(QString::fromLocal8Bit(
 241                                                 proc_->readAllStandardOutput().data()));
 242                 if (!os::is_terminal(os::STDERR))
 243                         cerr << fromqstr(QString::fromLocal8Bit(
 244                                                 proc_->readAllStandardError().data()));
 245         }
 246 }
 247
 248 void SystemcallPrivate::stdOut()
 249 {
 250         if (proc_ && showout_) {
 251                 char c;
 252                 proc_->setReadChannel(QProcess::StandardOutput);
 253                 while (proc_->getChar(&c)) {
 254                         outdata_[outindex_++] = c;
 255                         if (c == '\n' || outindex_ + 1 == bufsize_) {
 256                                 outdata_[outindex_] = '\0';
 257                                 outindex_ = 0;
 258                                 cout << outdata_;
 259                         }
 260                 }
 261         }
 262 }
 263
 264
 265 void SystemcallPrivate::stdErr()
 266 {
 267         if (proc_ && showerr_) {
 268                 char c;
 269                 proc_->setReadChannel(QProcess::StandardError);
 270                 while (proc_->getChar(&c)) {
 271                         errdata_[errindex_++] = c;
 272                         if (c == '\n' || errindex_ + 1 == bufsize_) {
 273                                 errdata_[errindex_] = '\0';
 274                                 errindex_ = 0;
 275                                 cerr << errdata_;
 276                         }
 277                 }
 278         }
 279 }
 280
 281
 282 void SystemcallPrivate::processError(QProcess::ProcessError err)
 283 {
 284         state = Error;
 285 }
 286
 287
 288 QString SystemcallPrivate::errorMessage() const
 289 {
 290         if (!proc_)
 291                 return "No QProcess available";
 292
 293         QString message;
 294         switch (proc_->error()) {
 295                 case QProcess::FailedToStart:
 296                         message = "The process failed to start. Either the invoked program is missing, "
 297                                       "or you may have insufficient permissions to invoke the program.";
 298                         break;
 299                 case QProcess::Crashed:
 300                         message = "The process crashed some time after starting successfully.";
 301                         break;
 302                 case QProcess::Timedout:
 303                         message = "The process timed out. It might be restarted automatically.";
 304                         break;
 305                 case QProcess::WriteError:
 306                         message = "An error occurred when attempting to write to the process-> For example, "
 307                                       "the process may not be running, or it may have closed its input channel.";
 308                         break;
 309                 case QProcess::ReadError:
 310                         message = "An error occurred when attempting to read from the process-> For example, "
 311                                       "the process may not be running.";
 312                         break;
 313                 case QProcess::UnknownError:
 314                 default:
 315                         message = "An unknown error occured.";
 316                         break;
 317         }
 318         return message;
 319 }
 320
 321
 322 void SystemcallPrivate::processStarted()
 323 {
 324         state = Running;
 325         // why do we get two started signals?
 326         //disconnect(proc_, SIGNAL(started()), this, SLOT(processStarted()));
 327 }
 328
 329
 330 void SystemcallPrivate::processFinished(int, QProcess::ExitStatus status)
 331 {
 332         state = Finished;
 333 }
 334
 335
 336 QString SystemcallPrivate::exitStatusMessage() const
 337 {
 338         if (!proc_)
 339                 return "No QProcess available";
 340
 341         QString message;
 342         switch (proc_->exitStatus()) {
 343                 case QProcess::NormalExit:
 344                         message = "The process exited normally.";
 345                         break;
 346                 case QProcess::CrashExit:
 347                         message = "The process crashed.";
 348                         break;
 349                 default:
 350                         message = "Unknown exit state.";
 351                         break;
 352         }
 353         return message;
 354 }
 355
 356 int SystemcallPrivate::exitCode()
 357 {
 358         if (!proc_)
 359                 return -1;
 360
 361         return proc_->exitCode();
 362 }
 363
 364
 365 QProcess* SystemcallPrivate::releaseProcess()
 366 {
 367         QProcess* released = proc_;
 368         proc_ = 0;
 369         return released;
 370 }
 371
 372
 373 void SystemcallPrivate::killProcess()
 374 {
 375         killProcess(proc_);
 376 }
 377
 378 void SystemcallPrivate::killProcess(QProcess * p)
 379 {
 380         if (p) {
 381                 p->disconnect();
 382                 p->closeReadChannel(QProcess::StandardOutput);
 383                 p->closeReadChannel(QProcess::StandardError);
 384                 p->close();
 385                 delete p;
 386         }
 387 }
 388
 389
 390
 391 #include "moc_SystemcallPrivate.cpp"
 392 #endif
 393
 394 } // namespace support
 395 } // namespace lyx