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/environment.h"
  18 #include "support/filetools.h"
  19 #include "support/lstrings.h"
  20 #include "support/qstring_helpers.h"
  21 #include "support/Systemcall.h"
  22 #include "support/SystemcallPrivate.h"
  23 #include "support/os.h"
  24 #include "support/ProgressInterface.h"
  25
  26 #include "LyXRC.h"
  27
  28 #include <cstdlib>
  29 #include <iostream>
  30
  31 #include <QProcess>
  32 #include <QTime>
  33 #include <QThread>
  34 #include <QCoreApplication>
  35 #include <QDebug>
  36
  37 #define USE_QPROCESS
  38
  39
  40 struct Sleep : QThread
  41 {
  42         static void millisec(unsigned long ms)
  43         {
  44                 QThread::usleep(ms * 1000);
  45         }
  46 };
  47
  48
  49
  50
  51 using namespace std;
  52
  53 namespace lyx {
  54 namespace support {
  55
  56
  57 class ProgressDummy : public ProgressInterface
  58 {
  59 public:
  60         ProgressDummy() {}
  61
  62         void processStarted(QString const &) {}
  63         void processFinished(QString const &) {}
  64         void appendMessage(QString const &) {}
  65         void appendError(QString const &) {}
  66         void clearMessages() {}
  67         void lyxerrFlush() {}
  68
  69         void lyxerrConnect() {}
  70         void lyxerrDisconnect() {}
  71
  72         void warning(QString const &, QString const &) {}
  73         void toggleWarning(QString const &, QString const &, QString const &) {}
  74         void error(QString const &, QString const &) {}
  75         void information(QString const &, QString const &) {}
  76 };
  77
  78
  79 static ProgressInterface* progress_instance = 0;
  80
  81 void ProgressInterface::setInstance(ProgressInterface* p)
  82 {
  83         progress_instance = p;
  84 }
  85
  86
  87 ProgressInterface* ProgressInterface::instance()
  88 {
  89         if (!progress_instance) {
  90                 static ProgressDummy dummy;
  91                 return &dummy;
  92         }
  93         return progress_instance;
  94 }
  95
  96
  97
  98
  99 // Reuse of instance
 100 #ifndef USE_QPROCESS
 101 int Systemcall::startscript(Starttype how, string const & what,
 102                             std::string const & path, bool /*process_events*/)
 103 {
 104         string command;
 105         string const texinputs = os::latex_path_list(
 106                         replaceCurdirPath(path, lyxrc.texinputs_prefix));
 107         string const sep = string(1, os::path_separator(os::TEXENGINE));
 108         string const env = getEnv("TEXINPUTS");
 109
 110         switch (os::shell()) {
 111         case os::UNIX:
 112                 command = path.empty() || lyxrc.texinputs_prefix.empty() ? what
 113                         : "env TEXINPUTS='." + sep + texinputs
 114                                              + sep + env + "' " + what;
 115                 break;
 116         case os::CMD_EXE:
 117                 command = path.empty() || lyxrc.texinputs_prefix.empty() ? what
 118                         : "set TEXINPUTS=." + sep + texinputs
 119                                             + sep + env + " & " + what;
 120                 break;
 121         }
 122
 123         if (how == DontWait) {
 124                 switch (os::shell()) {
 125                 case os::UNIX:
 126                         command += " &";
 127                         break;
 128                 case os::CMD_EXE:
 129                         command = "start /min " + command;
 130                         break;
 131                 }
 132         }
 133
 134         return ::system(command.c_str());
 135 }
 136
 137 #else
 138
 139 namespace {
 140
 141 /*
 142  * This is a parser that (mostly) mimics the behavior of a posix shell but
 143  * its output is tailored for being processed by QProcess.
 144  *
 145  * The escape character is the backslash.
 146  * A backslash that is not quoted preserves the literal value of the following
 147  * character, with the exception of a double-quote '"'. If a double-quote
 148  * follows a backslash, it will be replaced by three consecutive double-quotes
 149  * (this is how the QProcess parser recognizes a '"' as a simple character
 150  * instead of a quoting character). Thus, for example:
 151  *     \\  ->  \
 152  *     \a  ->  a
 153  *     \"  ->  """
 154  *
 155  * Single-quotes.
 156  * Characters enclosed in single-quotes ('') have their literal value preserved.
 157  * A single-quote cannot occur within single-quotes. Indeed, a backslash cannot
 158  * be used to escape a single-quote in a single-quoted string. In other words,
 159  * anything enclosed in single-quotes is passed as is, but the single-quotes
 160  * themselves are eliminated. Thus, for example:
 161  *    '\'    ->  \
 162  *    '\\'   ->  \\
 163  *    '\a'   ->  \a
 164  *    'a\"b' ->  a\"b
 165  *
 166  * Double-quotes.
 167  * Characters enclosed in double-quotes ("") have their literal value preserved,
 168  * with the exception of the backslash. The backslash retains its special
 169  * meaning as an escape character only when followed by a double-quote.
 170  * Contrarily to the behavior of a posix shell, the double-quotes themselves
 171  * are *not* eliminated. Thus, for example:
 172  *    "\\"   ->  "\\"
 173  *    "\a"   ->  "\a"
 174  *    "a\"b" ->  "a"""b"
 175  */
 176 string const parsecmd(string const & inputcmd, string & outfile)
 177 {
 178         bool in_single_quote = false;
 179         bool in_double_quote = false;
 180         bool escaped = false;
 181         string cmd;
 182
 183         for (size_t i = 0; i < inputcmd.length(); ++i) {
 184                 char c = inputcmd[i];
 185                 if (c == '\'') {
 186                         if (in_double_quote || escaped) {
 187                                 if (in_double_quote && escaped)
 188                                         cmd += '\\';
 189                                 cmd += c;
 190                         } else
 191                                 in_single_quote = !in_single_quote;
 192                         escaped = false;
 193                         continue;
 194                 }
 195                 if (in_single_quote) {
 196                         cmd += c;
 197                         continue;
 198                 }
 199                 if (c == '"') {
 200                         if (escaped) {
 201                                 cmd += "\"\"\"";
 202                                 escaped = false;
 203                         } else {
 204                                 cmd += c;
 205                                 in_double_quote = !in_double_quote;
 206                         }
 207                 } else if (c == '\\' && !escaped) {
 208                         escaped = !escaped;
 209                 } else if (c == '>' && !(in_double_quote || escaped)) {
 210                         outfile = trim(inputcmd.substr(i + 1), " \"");
 211                         return trim(cmd);
 212                 } else {
 213                         if (escaped && in_double_quote)
 214                                 cmd += '\\';
 215                         cmd += c;
 216                         escaped = false;
 217                 }
 218         }
 219         outfile.erase();
 220         return cmd;
 221 }
 222
 223 } // namespace anon
 224
 225
 226
 227 int Systemcall::startscript(Starttype how, string const & what,
 228                             string const & path, bool process_events)
 229 {
 230         string outfile;
 231         QString cmd = toqstr(parsecmd(what, outfile));
 232
 233         SystemcallPrivate d(outfile);
 234
 235
 236         d.startProcess(cmd, path);
 237         if (!d.waitWhile(SystemcallPrivate::Starting, process_events, -1)) {
 238                 LYXERR0("Systemcall: '" << cmd << "' did not start!");
 239                 LYXERR0("error " << d.errorMessage());
 240                 return 10;
 241         }
 242
 243         if (how == DontWait) {
 244                 QProcess* released = d.releaseProcess();
 245                 (void) released; // TODO who deletes it?
 246                 return 0;
 247         }
 248
 249         if (!d.waitWhile(SystemcallPrivate::Running, process_events,
 250                          os::timeout_min() * 60 * 1000)) {
 251                 LYXERR0("Systemcall: '" << cmd << "' did not finish!");
 252                 LYXERR0("error " << d.errorMessage());
 253                 LYXERR0("status " << d.exitStatusMessage());
 254                 return 20;
 255         }
 256
 257         int const exit_code = d.exitCode();
 258         if (exit_code) {
 259                 LYXERR0("Systemcall: '" << cmd << "' finished with exit code " << exit_code);
 260         }
 261
 262         return exit_code;
 263 }
 264
 265
 266 SystemcallPrivate::SystemcallPrivate(const std::string& of) :
 267                                 process_(new QProcess),
 268                                 out_index_(0),
 269                                 err_index_(0),
 270                                 out_file_(of),
 271                                 process_events_(false)
 272 {
 273         if (!out_file_.empty()) {
 274                 // Check whether we have to simply throw away the output.
 275                 if (out_file_ != os::nulldev())
 276                         process_->setStandardOutputFile(toqstr(out_file_));
 277         }
 278
 279         connect(process_, SIGNAL(readyReadStandardOutput()), SLOT(stdOut()));
 280         connect(process_, SIGNAL(readyReadStandardError()), SLOT(stdErr()));
 281         connect(process_, SIGNAL(error(QProcess::ProcessError)), SLOT(processError(QProcess::ProcessError)));
 282         connect(process_, SIGNAL(started()), this, SLOT(processStarted()));
 283         connect(process_, SIGNAL(finished(int, QProcess::ExitStatus)), SLOT(processFinished(int, QProcess::ExitStatus)));
 284 }
 285
 286
 287
 288 void SystemcallPrivate::startProcess(QString const & cmd, string const & path)
 289 {
 290         cmd_ = cmd;
 291         if (process_) {
 292                 if (!path.empty() && !lyxrc.texinputs_prefix.empty()) {
 293                         QString const texinputs = toqstr(os::latex_path_list(
 294                                 replaceCurdirPath(path, lyxrc.texinputs_prefix)));
 295                         QChar const sep = os::path_separator(os::TEXENGINE);
 296                         QString const prefix = QLatin1String("TEXINPUTS=.")
 297                                                 + sep + texinputs + sep;
 298                         QStringList env = QProcess::systemEnvironment();
 299                         if (env.filter("TEXINPUTS=").isEmpty())
 300                                 env << prefix;
 301                         else
 302                                 env.replaceInStrings(QRegExp("^TEXINPUTS=(.*)"),
 303                                                      prefix + "\\1");
 304                         process_->setEnvironment(env);
 305                 }
 306                 state = SystemcallPrivate::Starting;
 307                 process_->start(cmd_);
 308         }
 309 }
 310
 311
 312 void SystemcallPrivate::processEvents()
 313 {
 314         if(process_events_) {
 315                 QCoreApplication::processEvents(/*QEventLoop::ExcludeUserInputEvents*/);
 316         }
 317 }
 318
 319
 320 void SystemcallPrivate::waitAndProcessEvents()
 321 {
 322         Sleep::millisec(100);
 323         processEvents();
 324 }
 325
 326
 327 bool SystemcallPrivate::waitWhile(State waitwhile, bool process_events, int timeout)
 328 {
 329         if (!process_)
 330                 return false;
 331
 332         process_events_ = process_events;
 333
 334         // Block GUI while waiting,
 335         // relay on QProcess' wait functions
 336         if (!process_events_) {
 337                 if (waitwhile == Starting)
 338                         return process_->waitForStarted(timeout);
 339                 if (waitwhile == Running)
 340                         return process_->waitForFinished(timeout);
 341                 return false;
 342         }
 343
 344         // process events while waiting, no timeout
 345         if (timeout == -1) {
 346                 while (state == waitwhile && state != Error) {
 347                         waitAndProcessEvents();
 348                 }
 349                 return state != Error;
 350         }
 351
 352         // process events while waiting whith timeout
 353         QTime timer;
 354         timer.start();
 355         while (state == waitwhile && state != Error && timer.elapsed() < timeout) {
 356                 waitAndProcessEvents();
 357         }
 358         return (state != Error) && (timer.elapsed() < timeout);
 359 }
 360
 361
 362 SystemcallPrivate::~SystemcallPrivate()
 363 {
 364         if (out_index_) {
 365                 out_data_[out_index_] = '\0';
 366                 out_index_ = 0;
 367                 cout << out_data_;
 368         }
 369         cout.flush();
 370         if (err_index_) {
 371                 err_data_[err_index_] = '\0';
 372                 err_index_ = 0;
 373                 cerr << err_data_;
 374         }
 375         cerr.flush();
 376
 377         killProcess();
 378 }
 379
 380
 381 void SystemcallPrivate::stdOut()
 382 {
 383         if (process_) {
 384                 char c;
 385                 process_->setReadChannel(QProcess::StandardOutput);
 386                 while (process_->getChar(&c)) {
 387                         out_data_[out_index_++] = c;
 388                         if (c == '\n' || out_index_ + 1 == buffer_size_) {
 389                                 out_data_[out_index_] = '\0';
 390                                 out_index_ = 0;
 391                                 ProgressInterface::instance()->appendMessage(QString::fromLocal8Bit(out_data_));
 392                                 cout << out_data_;
 393                         }
 394                 }
 395         }
 396 }
 397
 398
 399 void SystemcallPrivate::stdErr()
 400 {
 401         if (process_) {
 402                 char c;
 403                 process_->setReadChannel(QProcess::StandardError);
 404                 while (process_->getChar(&c)) {
 405                         err_data_[err_index_++] = c;
 406                         if (c == '\n' || err_index_ + 1 == buffer_size_) {
 407                                 err_data_[err_index_] = '\0';
 408                                 err_index_ = 0;
 409                                 ProgressInterface::instance()->appendError(QString::fromLocal8Bit(err_data_));
 410                                 cerr << err_data_;
 411                         }
 412                 }
 413         }
 414 }
 415
 416
 417 void SystemcallPrivate::processStarted()
 418 {
 419         if (state != Running) {
 420                 state = Running;
 421                 ProgressInterface::instance()->processStarted(cmd_);
 422         }
 423 }
 424
 425
 426 void SystemcallPrivate::processFinished(int, QProcess::ExitStatus)
 427 {
 428         if (state != Finished) {
 429                 state = Finished;
 430                 ProgressInterface::instance()->processFinished(cmd_);
 431         }
 432 }
 433
 434
 435 void SystemcallPrivate::processError(QProcess::ProcessError)
 436 {
 437         state = Error;
 438         ProgressInterface::instance()->appendError(errorMessage());
 439 }
 440
 441
 442 QString SystemcallPrivate::errorMessage() const
 443 {
 444         if (!process_)
 445                 return "No QProcess available";
 446
 447         QString message;
 448         switch (process_->error()) {
 449                 case QProcess::FailedToStart:
 450                         message = "The process failed to start. Either the invoked program is missing, "
 451                                       "or you may have insufficient permissions to invoke the program.";
 452                         break;
 453                 case QProcess::Crashed:
 454                         message = "The process crashed some time after starting successfully.";
 455                         break;
 456                 case QProcess::Timedout:
 457                         message = "The process timed out. It might be restarted automatically.";
 458                         break;
 459                 case QProcess::WriteError:
 460                         message = "An error occurred when attempting to write to the process-> For example, "
 461                                       "the process may not be running, or it may have closed its input channel.";
 462                         break;
 463                 case QProcess::ReadError:
 464                         message = "An error occurred when attempting to read from the process-> For example, "
 465                                       "the process may not be running.";
 466                         break;
 467                 case QProcess::UnknownError:
 468                 default:
 469                         message = "An unknown error occured.";
 470                         break;
 471         }
 472         return message;
 473 }
 474
 475
 476 QString SystemcallPrivate::exitStatusMessage() const
 477 {
 478         if (!process_)
 479                 return "No QProcess available";
 480
 481         QString message;
 482         switch (process_->exitStatus()) {
 483                 case QProcess::NormalExit:
 484                         message = "The process exited normally.";
 485                         break;
 486                 case QProcess::CrashExit:
 487                         message = "The process crashed.";
 488                         break;
 489                 default:
 490                         message = "Unknown exit state.";
 491                         break;
 492         }
 493         return message;
 494 }
 495
 496
 497 int SystemcallPrivate::exitCode()
 498 {
 499         if (!process_)
 500                 return -1;
 501
 502         return process_->exitCode();
 503 }
 504
 505
 506 QProcess* SystemcallPrivate::releaseProcess()
 507 {
 508         QProcess* released = process_;
 509         process_ = 0;
 510         return released;
 511 }
 512
 513
 514 void SystemcallPrivate::killProcess()
 515 {
 516         killProcess(process_);
 517 }
 518
 519
 520 void SystemcallPrivate::killProcess(QProcess * p)
 521 {
 522         if (p) {
 523                 p->disconnect();
 524                 p->closeReadChannel(QProcess::StandardOutput);
 525                 p->closeReadChannel(QProcess::StandardError);
 526                 p->close();
 527                 delete p;
 528         }
 529 }
 530
 531
 532
 533 #include "moc_SystemcallPrivate.cpp"
 534 #endif
 535
 536 } // namespace support
 537 } // namespace lyx