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/filetools.h"
  18 #include "support/lstrings.h"
  19 #include "support/qstring_helpers.h"
  20 #include "support/Systemcall.h"
  21 #include "support/SystemcallPrivate.h"
  22 #include "support/os.h"
  23 #include "support/ProgressInterface.h"
  24
  25 #include "LyXRC.h"
  26
  27 #include <cstdlib>
  28 #include <iostream>
  29
  30 #include <QProcess>
  31 #include <QTime>
  32 #include <QThread>
  33 #include <QCoreApplication>
  34 #include <QDebug>
  35
  36 #define USE_QPROCESS
  37
  38
  39 struct Sleep : QThread
  40 {
  41         static void millisec(unsigned long ms)
  42         {
  43                 QThread::usleep(ms * 1000);
  44         }
  45 };
  46
  47
  48
  49
  50 using namespace std;
  51
  52 namespace lyx {
  53 namespace support {
  54
  55
  56 class ProgressDummy : public ProgressInterface
  57 {
  58 public:
  59         ProgressDummy() {}
  60
  61         void processStarted(QString const &) {}
  62         void processFinished(QString const &) {}
  63         void appendMessage(QString const &) {}
  64         void appendError(QString const &) {}
  65         void clearMessages() {}
  66         void lyxerrFlush() {}
  67
  68         void lyxerrConnect() {}
  69         void lyxerrDisconnect() {}
  70
  71         void warning(QString const &, QString const &) {}
  72         void toggleWarning(QString const &, QString const &, QString const &) {}
  73         void error(QString const &, QString const &) {}
  74         void information(QString const &, QString const &) {}
  75 };
  76
  77
  78 static ProgressInterface* progress_instance = 0;
  79
  80 void ProgressInterface::setInstance(ProgressInterface* p)
  81 {
  82         progress_instance = p;
  83 }
  84
  85
  86 ProgressInterface* ProgressInterface::instance()
  87 {
  88         if (!progress_instance) {
  89                 static ProgressDummy dummy;
  90                 return &dummy;
  91         }
  92         return progress_instance;
  93 }
  94
  95
  96
  97
  98 // Reuse of instance
  99 #ifndef USE_QPROCESS
 100 int Systemcall::startscript(Starttype how, string const & what,
 101                             std::string const & path, bool /*process_events*/)
 102 {
 103         string const python_call = "python -tt";
 104         string command = to_filesystem8bit(from_utf8(latexEnvCmdPrefix(path)));
 105
 106         if (prefixIs(what, python_call))
 107                 command += os::python() + what.substr(python_call.length());
 108         else
 109                 command += what;
 110
 111         if (how == DontWait) {
 112                 switch (os::shell()) {
 113                 case os::UNIX:
 114                         command += " &";
 115                         break;
 116                 case os::CMD_EXE:
 117                         command = "start /min " + command;
 118                         break;
 119                 }
 120         } else if (os::shell() == os::CMD_EXE)
 121                 command = subst(command, "cmd /d /c ", "");
 122
 123         return ::system(command.c_str());
 124 }
 125
 126 #else
 127
 128 namespace {
 129
 130 /*
 131  * This is a parser that (mostly) mimics the behavior of a posix shell as
 132  * regards quoting, but its output is tailored for being processed by QProcess.
 133  * Note that shell metacharacters are not parsed and only output redirection
 134  * is taken into account.
 135  *
 136  * The escape character is the backslash.
 137  * A backslash that is not quoted preserves the literal value of the following
 138  * character, with the exception of a double-quote '"'. If a double-quote
 139  * follows a backslash, it will be replaced by three consecutive double-quotes
 140  * (this is how the QProcess parser recognizes a '"' as a simple character
 141  * instead of a quoting character). Thus, for example:
 142  *     \\  ->  \
 143  *     \a  ->  a
 144  *     \"  ->  """
 145  *
 146  * Single-quotes.
 147  * Characters enclosed in single-quotes ('') have their literal value preserved.
 148  * A single-quote cannot occur within single-quotes. Indeed, a backslash cannot
 149  * be used to escape a single-quote in a single-quoted string. In other words,
 150  * anything enclosed in single-quotes is passed as is, but the single-quotes
 151  * themselves are eliminated. Thus, for example:
 152  *    '\'    ->  \
 153  *    '\\'   ->  \\
 154  *    '\a'   ->  \a
 155  *    'a\"b' ->  a\"b
 156  *
 157  * Double-quotes.
 158  * Characters enclosed in double-quotes ("") have their literal value preserved,
 159  * with the exception of the backslash. The backslash retains its special
 160  * meaning as an escape character only when followed by a double-quote.
 161  * Contrarily to the behavior of a posix shell, the double-quotes themselves
 162  * are *not* eliminated. Thus, for example:
 163  *    "\\"   ->  "\\"
 164  *    "\a"   ->  "\a"
 165  *    "a\"b" ->  "a"""b"
 166  */
 167 string const parsecmd(string const & incmd, string & outfile, string & errfile)
 168 {
 169         bool in_single_quote = false;
 170         bool in_double_quote = false;
 171         bool escaped = false;
 172         string const python_call = "python -tt";
 173         vector<string> outcmd(3);
 174         size_t start = 0;
 175
 176         if (prefixIs(incmd, python_call)) {
 177                 outcmd[0] = os::python();
 178                 start = python_call.length();
 179         }
 180
 181         for (size_t i = start, o = 0; i < incmd.length(); ++i) {
 182                 char c = incmd[i];
 183                 if (c == '\'') {
 184                         if (in_double_quote || escaped) {
 185                                 if (in_double_quote && escaped)
 186                                         outcmd[o] += '\\';
 187                                 outcmd[o] += c;
 188                         } else
 189                                 in_single_quote = !in_single_quote;
 190                         escaped = false;
 191                         continue;
 192                 }
 193                 if (in_single_quote) {
 194                         outcmd[o] += c;
 195                         continue;
 196                 }
 197                 if (c == '"') {
 198                         if (escaped) {
 199                                 // Don't triple double-quotes for redirection
 200                                 // files as these won't be parsed by QProcess
 201                                 outcmd[o] += string(o ? "\"" : "\"\"\"");
 202                                 escaped = false;
 203                         } else {
 204                                 outcmd[o] += 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                         if (suffixIs(outcmd[o], " 2")) {
 211                                 outcmd[o] = rtrim(outcmd[o], "2");
 212                                 o = 2;
 213                         } else {
 214                                 if (suffixIs(outcmd[o], " 1"))
 215                                         outcmd[o] = rtrim(outcmd[o], "1");
 216                                 o = 1;
 217                         }
 218                 } else {
 219                         if (escaped && in_double_quote)
 220                                 outcmd[o] += '\\';
 221                         outcmd[o] += c;
 222                         escaped = false;
 223                 }
 224         }
 225         outfile = trim(outcmd[1], " \"");
 226         errfile = trim(outcmd[2], " \"");
 227         return trim(outcmd[0]);
 228 }
 229
 230 } // namespace anon
 231
 232
 233
 234 int Systemcall::startscript(Starttype how, string const & what,
 235                             string const & path, bool process_events)
 236 {
 237         lyxerr << "\nRunning: " << what << endl;
 238
 239         string outfile;
 240         string errfile;
 241         QString cmd = QString::fromLocal8Bit(
 242                         parsecmd(what, outfile, errfile).c_str());
 243
 244         SystemcallPrivate d(outfile, errfile);
 245
 246
 247         d.startProcess(cmd, path);
 248         if (!d.waitWhile(SystemcallPrivate::Starting, process_events, -1)) {
 249                 LYXERR0("Systemcall: '" << cmd << "' did not start!");
 250                 LYXERR0("error " << d.errorMessage());
 251                 return 10;
 252         }
 253
 254         if (how == DontWait) {
 255                 QProcess* released = d.releaseProcess();
 256                 (void) released; // TODO who deletes it?
 257                 return 0;
 258         }
 259
 260         if (!d.waitWhile(SystemcallPrivate::Running, process_events,
 261                          os::timeout_min() * 60 * 1000)) {
 262                 LYXERR0("Systemcall: '" << cmd << "' did not finish!");
 263                 LYXERR0("error " << d.errorMessage());
 264                 LYXERR0("status " << d.exitStatusMessage());
 265                 return 20;
 266         }
 267
 268         int const exit_code = d.exitCode();
 269         if (exit_code) {
 270                 LYXERR0("Systemcall: '" << cmd << "' finished with exit code " << exit_code);
 271         }
 272
 273         return exit_code;
 274 }
 275
 276
 277 SystemcallPrivate::SystemcallPrivate(std::string const & of,
 278                                      std::string const & ef) :
 279                                 process_(new QProcess),
 280                                 out_index_(0),
 281                                 err_index_(0),
 282                                 out_file_(of),
 283                                 err_file_(ef),
 284                                 process_events_(false)
 285 {
 286         if (!out_file_.empty()) {
 287                 if (out_file_[0] == '&') {
 288                         if (subst(out_file_, " ", "") == "&2"
 289                             && err_file_[0] != '&') {
 290                                 out_file_ = err_file_;
 291                                 process_->setProcessChannelMode(
 292                                                 QProcess::MergedChannels);
 293                         } else {
 294                                 if (err_file_[0] == '&') {
 295                                         // Leave alone things such as
 296                                         // "1>&2 2>&1". Should not be harmful,
 297                                         // but let's give anyway a warning.
 298                                         LYXERR0("Unsupported stdout/stderr redirect.");
 299                                         err_file_.erase();
 300                                 } else {
 301                                         LYXERR0("Ambiguous stdout redirect: "
 302                                                 << out_file_);
 303                                 }
 304                                 out_file_ = os::nulldev();
 305                         }
 306                 }
 307                 // Check whether we have to set the output file.
 308                 if (out_file_ != os::nulldev()) {
 309                         process_->setStandardOutputFile(QString::fromLocal8Bit(
 310                                                         out_file_.c_str()));
 311                 }
 312         }
 313         if (!err_file_.empty()) {
 314                 if (err_file_[0] == '&') {
 315                         if (subst(err_file_, " ", "") == "&1"
 316                             && out_file_[0] != '&') {
 317                                 process_->setProcessChannelMode(
 318                                                 QProcess::MergedChannels);
 319                         } else {
 320                                 LYXERR0("Ambiguous stderr redirect: "
 321                                         << err_file_);
 322                         }
 323                         // In MergedChannels mode stderr goes to stdout.
 324                         err_file_ = os::nulldev();
 325                 }
 326                 // Check whether we have to set the error file.
 327                 if (err_file_ != os::nulldev()) {
 328                         process_->setStandardErrorFile(QString::fromLocal8Bit(
 329                                                         err_file_.c_str()));
 330                 }
 331         }
 332
 333         connect(process_, SIGNAL(readyReadStandardOutput()), SLOT(stdOut()));
 334         connect(process_, SIGNAL(readyReadStandardError()), SLOT(stdErr()));
 335         connect(process_, SIGNAL(error(QProcess::ProcessError)), SLOT(processError(QProcess::ProcessError)));
 336         connect(process_, SIGNAL(started()), this, SLOT(processStarted()));
 337         connect(process_, SIGNAL(finished(int, QProcess::ExitStatus)), SLOT(processFinished(int, QProcess::ExitStatus)));
 338 }
 339
 340
 341 void SystemcallPrivate::startProcess(QString const & cmd, string const & path)
 342 {
 343         cmd_ = cmd;
 344         if (process_) {
 345                 state = SystemcallPrivate::Starting;
 346                 process_->start(toqstr(latexEnvCmdPrefix(path)) + cmd_);
 347         }
 348 }
 349
 350
 351 void SystemcallPrivate::processEvents()
 352 {
 353         if(process_events_) {
 354                 QCoreApplication::processEvents(/*QEventLoop::ExcludeUserInputEvents*/);
 355         }
 356 }
 357
 358
 359 void SystemcallPrivate::waitAndProcessEvents()
 360 {
 361         Sleep::millisec(100);
 362         processEvents();
 363 }
 364
 365
 366 bool SystemcallPrivate::waitWhile(State waitwhile, bool process_events, int timeout)
 367 {
 368         if (!process_)
 369                 return false;
 370
 371         process_events_ = process_events;
 372
 373         // Block GUI while waiting,
 374         // relay on QProcess' wait functions
 375         if (!process_events_) {
 376                 if (waitwhile == Starting)
 377                         return process_->waitForStarted(timeout);
 378                 if (waitwhile == Running)
 379                         return process_->waitForFinished(timeout);
 380                 return false;
 381         }
 382
 383         // process events while waiting, no timeout
 384         if (timeout == -1) {
 385                 while (state == waitwhile && state != Error) {
 386                         waitAndProcessEvents();
 387                 }
 388                 return state != Error;
 389         }
 390
 391         // process events while waiting whith timeout
 392         QTime timer;
 393         timer.start();
 394         while (state == waitwhile && state != Error && timer.elapsed() < timeout) {
 395                 waitAndProcessEvents();
 396         }
 397         return (state != Error) && (timer.elapsed() < timeout);
 398 }
 399
 400
 401 SystemcallPrivate::~SystemcallPrivate()
 402 {
 403         if (out_index_) {
 404                 out_data_[out_index_] = '\0';
 405                 out_index_ = 0;
 406                 cout << out_data_;
 407         }
 408         cout.flush();
 409         if (err_index_) {
 410                 err_data_[err_index_] = '\0';
 411                 err_index_ = 0;
 412                 cerr << err_data_;
 413         }
 414         cerr.flush();
 415
 416         killProcess();
 417 }
 418
 419
 420 void SystemcallPrivate::stdOut()
 421 {
 422         if (process_) {
 423                 char c;
 424                 process_->setReadChannel(QProcess::StandardOutput);
 425                 while (process_->getChar(&c)) {
 426                         out_data_[out_index_++] = c;
 427                         if (c == '\n' || out_index_ + 1 == buffer_size_) {
 428                                 out_data_[out_index_] = '\0';
 429                                 out_index_ = 0;
 430                                 ProgressInterface::instance()->appendMessage(QString::fromLocal8Bit(out_data_));
 431                                 cout << out_data_;
 432                         }
 433                 }
 434         }
 435 }
 436
 437
 438 void SystemcallPrivate::stdErr()
 439 {
 440         if (process_) {
 441                 char c;
 442                 process_->setReadChannel(QProcess::StandardError);
 443                 while (process_->getChar(&c)) {
 444                         err_data_[err_index_++] = c;
 445                         if (c == '\n' || err_index_ + 1 == buffer_size_) {
 446                                 err_data_[err_index_] = '\0';
 447                                 err_index_ = 0;
 448                                 ProgressInterface::instance()->appendError(QString::fromLocal8Bit(err_data_));
 449                                 cerr << err_data_;
 450                         }
 451                 }
 452         }
 453 }
 454
 455
 456 void SystemcallPrivate::processStarted()
 457 {
 458         if (state != Running) {
 459                 state = Running;
 460                 ProgressInterface::instance()->processStarted(cmd_);
 461         }
 462 }
 463
 464
 465 void SystemcallPrivate::processFinished(int, QProcess::ExitStatus)
 466 {
 467         if (state != Finished) {
 468                 state = Finished;
 469                 ProgressInterface::instance()->processFinished(cmd_);
 470         }
 471 }
 472
 473
 474 void SystemcallPrivate::processError(QProcess::ProcessError)
 475 {
 476         state = Error;
 477         ProgressInterface::instance()->appendError(errorMessage());
 478 }
 479
 480
 481 QString SystemcallPrivate::errorMessage() const
 482 {
 483         if (!process_)
 484                 return "No QProcess available";
 485
 486         QString message;
 487         switch (process_->error()) {
 488                 case QProcess::FailedToStart:
 489                         message = "The process failed to start. Either the invoked program is missing, "
 490                                       "or you may have insufficient permissions to invoke the program.";
 491                         break;
 492                 case QProcess::Crashed:
 493                         message = "The process crashed some time after starting successfully.";
 494                         break;
 495                 case QProcess::Timedout:
 496                         message = "The process timed out. It might be restarted automatically.";
 497                         break;
 498                 case QProcess::WriteError:
 499                         message = "An error occurred when attempting to write to the process-> For example, "
 500                                       "the process may not be running, or it may have closed its input channel.";
 501                         break;
 502                 case QProcess::ReadError:
 503                         message = "An error occurred when attempting to read from the process-> For example, "
 504                                       "the process may not be running.";
 505                         break;
 506                 case QProcess::UnknownError:
 507                 default:
 508                         message = "An unknown error occured.";
 509                         break;
 510         }
 511         return message;
 512 }
 513
 514
 515 QString SystemcallPrivate::exitStatusMessage() const
 516 {
 517         if (!process_)
 518                 return "No QProcess available";
 519
 520         QString message;
 521         switch (process_->exitStatus()) {
 522                 case QProcess::NormalExit:
 523                         message = "The process exited normally.";
 524                         break;
 525                 case QProcess::CrashExit:
 526                         message = "The process crashed.";
 527                         break;
 528                 default:
 529                         message = "Unknown exit state.";
 530                         break;
 531         }
 532         return message;
 533 }
 534
 535
 536 int SystemcallPrivate::exitCode()
 537 {
 538         if (!process_)
 539                 return -1;
 540
 541         return process_->exitCode();
 542 }
 543
 544
 545 QProcess* SystemcallPrivate::releaseProcess()
 546 {
 547         QProcess* released = process_;
 548         process_ = 0;
 549         return released;
 550 }
 551
 552
 553 void SystemcallPrivate::killProcess()
 554 {
 555         killProcess(process_);
 556 }
 557
 558
 559 void SystemcallPrivate::killProcess(QProcess * p)
 560 {
 561         if (p) {
 562                 p->disconnect();
 563                 p->closeReadChannel(QProcess::StandardOutput);
 564                 p->closeReadChannel(QProcess::StandardError);
 565                 p->close();
 566                 delete p;
 567         }
 568 }
 569
 570
 571
 572 #include "moc_SystemcallPrivate.cpp"
 573 #endif
 574
 575 } // namespace support
 576 } // namespace lyx