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.
 134  *
 135  * The escape character is the backslash.
 136  * A backslash that is not quoted preserves the literal value of the following
 137  * character, with the exception of a double-quote '"'. If a double-quote
 138  * follows a backslash, it will be replaced by three consecutive double-quotes
 139  * (this is how the QProcess parser recognizes a '"' as a simple character
 140  * instead of a quoting character). Thus, for example:
 141  *     \\  ->  \
 142  *     \a  ->  a
 143  *     \"  ->  """
 144  *
 145  * Single-quotes.
 146  * Characters enclosed in single-quotes ('') have their literal value preserved.
 147  * A single-quote cannot occur within single-quotes. Indeed, a backslash cannot
 148  * be used to escape a single-quote in a single-quoted string. In other words,
 149  * anything enclosed in single-quotes is passed as is, but the single-quotes
 150  * themselves are eliminated. Thus, for example:
 151  *    '\'    ->  \
 152  *    '\\'   ->  \\
 153  *    '\a'   ->  \a
 154  *    'a\"b' ->  a\"b
 155  *
 156  * Double-quotes.
 157  * Characters enclosed in double-quotes ("") have their literal value preserved,
 158  * with the exception of the backslash. The backslash retains its special
 159  * meaning as an escape character only when followed by a double-quote.
 160  * Contrarily to the behavior of a posix shell, the double-quotes themselves
 161  * are *not* eliminated. Thus, for example:
 162  *    "\\"   ->  "\\"
 163  *    "\a"   ->  "\a"
 164  *    "a\"b" ->  "a"""b"
 165  */
 166 string const parsecmd(string const & incmd, string & infile, string & outfile,
 167                      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(4);
 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 if (c == '<' && !(in_double_quote || escaped)) {
 219                         o = 3;
 220                 } else {
 221                         if (escaped && in_double_quote)
 222                                 outcmd[o] += '\\';
 223                         outcmd[o] += c;
 224                         escaped = false;
 225                 }
 226         }
 227         infile  = trim(outcmd[3], " \"");
 228         outfile = trim(outcmd[1], " \"");
 229         errfile = trim(outcmd[2], " \"");
 230         return trim(outcmd[0]);
 231 }
 232
 233 } // namespace anon
 234
 235
 236
 237 int Systemcall::startscript(Starttype how, string const & what,
 238                             string const & path, bool process_events)
 239 {
 240         lyxerr << "\nRunning: " << what << endl;
 241
 242         string infile;
 243         string outfile;
 244         string errfile;
 245         QString cmd = QString::fromLocal8Bit(
 246                         parsecmd(what, infile, outfile, errfile).c_str());
 247
 248         SystemcallPrivate d(infile, outfile, errfile);
 249
 250
 251         d.startProcess(cmd, path);
 252         if (!d.waitWhile(SystemcallPrivate::Starting, process_events, -1)) {
 253                 LYXERR0("Systemcall: '" << cmd << "' did not start!");
 254                 LYXERR0("error " << d.errorMessage());
 255                 return 10;
 256         }
 257
 258         if (how == DontWait) {
 259                 QProcess* released = d.releaseProcess();
 260                 (void) released; // TODO who deletes it?
 261                 return 0;
 262         }
 263
 264         if (!d.waitWhile(SystemcallPrivate::Running, process_events,
 265                          os::timeout_min() * 60 * 1000)) {
 266                 LYXERR0("Systemcall: '" << cmd << "' did not finish!");
 267                 LYXERR0("error " << d.errorMessage());
 268                 LYXERR0("status " << d.exitStatusMessage());
 269                 return 20;
 270         }
 271
 272         int const exit_code = d.exitCode();
 273         if (exit_code) {
 274                 LYXERR0("Systemcall: '" << cmd << "' finished with exit code " << exit_code);
 275         }
 276
 277         return exit_code;
 278 }
 279
 280
 281 SystemcallPrivate::SystemcallPrivate(std::string const & sf,
 282                                      std::string const & of,
 283                                      std::string const & ef) :
 284                                 process_(new QProcess),
 285                                 out_index_(0),
 286                                 err_index_(0),
 287                                 in_file_(sf),
 288                                 out_file_(of),
 289                                 err_file_(ef),
 290                                 process_events_(false)
 291 {
 292         if (!in_file_.empty())
 293                 process_->setStandardInputFile(QString::fromLocal8Bit(in_file_.c_str()));
 294         if (!out_file_.empty()) {
 295                 if (out_file_[0] == '&') {
 296                         if (subst(out_file_, " ", "") == "&2"
 297                             && err_file_[0] != '&') {
 298                                 out_file_ = err_file_;
 299                                 process_->setProcessChannelMode(
 300                                                 QProcess::MergedChannels);
 301                         } else {
 302                                 if (err_file_[0] == '&') {
 303                                         // Leave alone things such as
 304                                         // "1>&2 2>&1". Should not be harmful,
 305                                         // but let's give anyway a warning.
 306                                         LYXERR0("Unsupported stdout/stderr redirect.");
 307                                         err_file_.erase();
 308                                 } else {
 309                                         LYXERR0("Ambiguous stdout redirect: "
 310                                                 << out_file_);
 311                                 }
 312                                 out_file_ = os::nulldev();
 313                         }
 314                 }
 315                 // Check whether we have to set the output file.
 316                 if (out_file_ != os::nulldev()) {
 317                         process_->setStandardOutputFile(QString::fromLocal8Bit(
 318                                                         out_file_.c_str()));
 319                 }
 320         }
 321         if (!err_file_.empty()) {
 322                 if (err_file_[0] == '&') {
 323                         if (subst(err_file_, " ", "") == "&1"
 324                             && out_file_[0] != '&') {
 325                                 process_->setProcessChannelMode(
 326                                                 QProcess::MergedChannels);
 327                         } else {
 328                                 LYXERR0("Ambiguous stderr redirect: "
 329                                         << err_file_);
 330                         }
 331                         // In MergedChannels mode stderr goes to stdout.
 332                         err_file_ = os::nulldev();
 333                 }
 334                 // Check whether we have to set the error file.
 335                 if (err_file_ != os::nulldev()) {
 336                         process_->setStandardErrorFile(QString::fromLocal8Bit(
 337                                                         err_file_.c_str()));
 338                 }
 339         }
 340
 341         connect(process_, SIGNAL(readyReadStandardOutput()), SLOT(stdOut()));
 342         connect(process_, SIGNAL(readyReadStandardError()), SLOT(stdErr()));
 343         connect(process_, SIGNAL(error(QProcess::ProcessError)), SLOT(processError(QProcess::ProcessError)));
 344         connect(process_, SIGNAL(started()), this, SLOT(processStarted()));
 345         connect(process_, SIGNAL(finished(int, QProcess::ExitStatus)), SLOT(processFinished(int, QProcess::ExitStatus)));
 346 }
 347
 348
 349 void SystemcallPrivate::startProcess(QString const & cmd, string const & path)
 350 {
 351         cmd_ = cmd;
 352         if (process_) {
 353                 state = SystemcallPrivate::Starting;
 354                 process_->start(toqstr(latexEnvCmdPrefix(path)) + cmd_);
 355         }
 356 }
 357
 358
 359 void SystemcallPrivate::processEvents()
 360 {
 361         if(process_events_) {
 362                 QCoreApplication::processEvents(/*QEventLoop::ExcludeUserInputEvents*/);
 363         }
 364 }
 365
 366
 367 void SystemcallPrivate::waitAndProcessEvents()
 368 {
 369         Sleep::millisec(100);
 370         processEvents();
 371 }
 372
 373
 374 bool SystemcallPrivate::waitWhile(State waitwhile, bool process_events, int timeout)
 375 {
 376         if (!process_)
 377                 return false;
 378
 379         process_events_ = process_events;
 380
 381         // Block GUI while waiting,
 382         // relay on QProcess' wait functions
 383         if (!process_events_) {
 384                 if (waitwhile == Starting)
 385                         return process_->waitForStarted(timeout);
 386                 if (waitwhile == Running)
 387                         return process_->waitForFinished(timeout);
 388                 return false;
 389         }
 390
 391         // process events while waiting, no timeout
 392         if (timeout == -1) {
 393                 while (state == waitwhile && state != Error) {
 394                         waitAndProcessEvents();
 395                 }
 396                 return state != Error;
 397         }
 398
 399         // process events while waiting whith timeout
 400         QTime timer;
 401         timer.start();
 402         while (state == waitwhile && state != Error && timer.elapsed() < timeout) {
 403                 waitAndProcessEvents();
 404         }
 405         return (state != Error) && (timer.elapsed() < timeout);
 406 }
 407
 408
 409 SystemcallPrivate::~SystemcallPrivate()
 410 {
 411         if (out_index_) {
 412                 out_data_[out_index_] = '\0';
 413                 out_index_ = 0;
 414                 cout << out_data_;
 415         }
 416         cout.flush();
 417         if (err_index_) {
 418                 err_data_[err_index_] = '\0';
 419                 err_index_ = 0;
 420                 cerr << err_data_;
 421         }
 422         cerr.flush();
 423
 424         killProcess();
 425 }
 426
 427
 428 void SystemcallPrivate::stdOut()
 429 {
 430         if (process_) {
 431                 char c;
 432                 process_->setReadChannel(QProcess::StandardOutput);
 433                 while (process_->getChar(&c)) {
 434                         out_data_[out_index_++] = c;
 435                         if (c == '\n' || out_index_ + 1 == buffer_size_) {
 436                                 out_data_[out_index_] = '\0';
 437                                 out_index_ = 0;
 438                                 ProgressInterface::instance()->appendMessage(QString::fromLocal8Bit(out_data_));
 439                                 cout << out_data_;
 440                         }
 441                 }
 442         }
 443 }
 444
 445
 446 void SystemcallPrivate::stdErr()
 447 {
 448         if (process_) {
 449                 char c;
 450                 process_->setReadChannel(QProcess::StandardError);
 451                 while (process_->getChar(&c)) {
 452                         err_data_[err_index_++] = c;
 453                         if (c == '\n' || err_index_ + 1 == buffer_size_) {
 454                                 err_data_[err_index_] = '\0';
 455                                 err_index_ = 0;
 456                                 ProgressInterface::instance()->appendError(QString::fromLocal8Bit(err_data_));
 457                                 cerr << err_data_;
 458                         }
 459                 }
 460         }
 461 }
 462
 463
 464 void SystemcallPrivate::processStarted()
 465 {
 466         if (state != Running) {
 467                 state = Running;
 468                 ProgressInterface::instance()->processStarted(cmd_);
 469         }
 470 }
 471
 472
 473 void SystemcallPrivate::processFinished(int, QProcess::ExitStatus)
 474 {
 475         if (state != Finished) {
 476                 state = Finished;
 477                 ProgressInterface::instance()->processFinished(cmd_);
 478         }
 479 }
 480
 481
 482 void SystemcallPrivate::processError(QProcess::ProcessError)
 483 {
 484         state = Error;
 485         ProgressInterface::instance()->appendError(errorMessage());
 486 }
 487
 488
 489 QString SystemcallPrivate::errorMessage() const
 490 {
 491         if (!process_)
 492                 return "No QProcess available";
 493
 494         QString message;
 495         switch (process_->error()) {
 496                 case QProcess::FailedToStart:
 497                         message = "The process failed to start. Either the invoked program is missing, "
 498                                       "or you may have insufficient permissions to invoke the program.";
 499                         break;
 500                 case QProcess::Crashed:
 501                         message = "The process crashed some time after starting successfully.";
 502                         break;
 503                 case QProcess::Timedout:
 504                         message = "The process timed out. It might be restarted automatically.";
 505                         break;
 506                 case QProcess::WriteError:
 507                         message = "An error occurred when attempting to write to the process-> For example, "
 508                                       "the process may not be running, or it may have closed its input channel.";
 509                         break;
 510                 case QProcess::ReadError:
 511                         message = "An error occurred when attempting to read from the process-> For example, "
 512                                       "the process may not be running.";
 513                         break;
 514                 case QProcess::UnknownError:
 515                 default:
 516                         message = "An unknown error occured.";
 517                         break;
 518         }
 519         return message;
 520 }
 521
 522
 523 QString SystemcallPrivate::exitStatusMessage() const
 524 {
 525         if (!process_)
 526                 return "No QProcess available";
 527
 528         QString message;
 529         switch (process_->exitStatus()) {
 530                 case QProcess::NormalExit:
 531                         message = "The process exited normally.";
 532                         break;
 533                 case QProcess::CrashExit:
 534                         message = "The process crashed.";
 535                         break;
 536                 default:
 537                         message = "Unknown exit state.";
 538                         break;
 539         }
 540         return message;
 541 }
 542
 543
 544 int SystemcallPrivate::exitCode()
 545 {
 546         if (!process_)
 547                 return -1;
 548
 549         return process_->exitCode();
 550 }
 551
 552
 553 QProcess* SystemcallPrivate::releaseProcess()
 554 {
 555         QProcess* released = process_;
 556         process_ = 0;
 557         return released;
 558 }
 559
 560
 561 void SystemcallPrivate::killProcess()
 562 {
 563         killProcess(process_);
 564 }
 565
 566
 567 void SystemcallPrivate::killProcess(QProcess * p)
 568 {
 569         if (p) {
 570                 p->disconnect();
 571                 p->closeReadChannel(QProcess::StandardOutput);
 572                 p->closeReadChannel(QProcess::StandardError);
 573                 p->close();
 574                 delete p;
 575         }
 576 }
 577
 578
 579
 580 #include "moc_SystemcallPrivate.cpp"
 581 #endif
 582
 583 } // namespace support
 584 } // namespace lyx