src/graphics/PreviewLoader.cpp

   1 /**
   2  * \file PreviewLoader.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Angus Leeming
   7  *
   8  * Full author contact details are available in file CREDITS.
   9  */
  10
  11 #include <config.h>
  12
  13 #include "PreviewLoader.h"
  14 #include "PreviewImage.h"
  15 #include "GraphicsCache.h"
  16
  17 #include "Buffer.h"
  18 #include "BufferParams.h"
  19 #include "Converter.h"
  20 #include "Encoding.h"
  21 #include "Format.h"
  22 #include "InsetIterator.h"
  23 #include "LaTeXFeatures.h"
  24 #include "LyXRC.h"
  25 #include "output.h"
  26 #include "OutputParams.h"
  27 #include "TexRow.h"
  28 #include "texstream.h"
  29
  30 #include "frontends/Application.h" // hexName
  31
  32 #include "insets/Inset.h"
  33
  34 #include "support/convert.h"
  35 #include "support/debug.h"
  36 #include "support/FileName.h"
  37 #include "support/filetools.h"
  38 #include "support/ForkedCalls.h"
  39 #include "support/lstrings.h"
  40
  41 #include "support/TempFile.h"
  42
  43 #include <atomic>
  44 #include <fstream>
  45 #include <iomanip>
  46 #include <memory>
  47 #include <mutex>
  48 #include <sstream>
  49
  50 #include <QTimer>
  51
  52 using namespace std;
  53 using namespace lyx::support;
  54
  55
  56
  57 namespace {
  58
  59 typedef pair<string, FileName> SnippetPair;
  60
  61 // A list of all snippets to be converted to previews
  62 typedef list<string> PendingSnippets;
  63
  64 // Each item in the vector is a pair<snippet, image file name>.
  65 typedef vector<SnippetPair> BitmapFile;
  66
  67
  68 FileName const unique_tex_filename(FileName const & bufferpath)
  69 {
  70         TempFile tempfile(bufferpath, "lyxpreviewXXXXXX.tex");
  71         tempfile.setAutoRemove(false);
  72         return tempfile.name();
  73 }
  74
  75
  76 void setAscentFractions(vector<double> & ascent_fractions,
  77                         FileName const & metrics_file)
  78 {
  79         // If all else fails, then the images will have equal ascents and
  80         // descents.
  81         vector<double>::iterator it  = ascent_fractions.begin();
  82         vector<double>::iterator end = ascent_fractions.end();
  83         fill(it, end, 0.5);
  84
  85         ifstream in(metrics_file.toFilesystemEncoding().c_str());
  86         if (!in.good()) {
  87                 LYXERR(lyx::Debug::GRAPHICS, "setAscentFractions(" << metrics_file << ")\n"
  88                         << "Unable to open file!");
  89                 return;
  90         }
  91
  92         bool error = false;
  93
  94         int snippet_counter = 1;
  95         while (!in.eof() && it != end) {
  96                 string snippet;
  97                 int id;
  98                 double ascent_fraction;
  99
 100                 in >> snippet >> id >> ascent_fraction;
 101
 102                 if (!in.good())
 103                         // eof after all
 104                         break;
 105
 106                 error = snippet != "Snippet";
 107                 if (error)
 108                         break;
 109
 110                 error = id != snippet_counter;
 111                 if (error)
 112                         break;
 113
 114                 *it = ascent_fraction;
 115
 116                 ++snippet_counter;
 117                 ++it;
 118         }
 119
 120         if (error) {
 121                 LYXERR(lyx::Debug::GRAPHICS, "setAscentFractions(" << metrics_file << ")\n"
 122                         << "Error reading file!\n");
 123         }
 124 }
 125
 126
 127 std::function <bool (SnippetPair const &)> FindFirst(string const & comp)
 128 {
 129         return [&comp](SnippetPair const & sp) { return sp.first == comp; };
 130 }
 131
 132
 133 /// Store info on a currently executing, forked process.
 134 class InProgress {
 135 public:
 136         ///
 137         InProgress() : pid(0) {}
 138         ///
 139         InProgress(string const & filename_base,
 140                    PendingSnippets const & pending,
 141                    string const & to_format);
 142         /// Remove any files left lying around and kill the forked process.
 143         void stop() const;
 144
 145         ///
 146         string command;
 147         ///
 148         FileName metrics_file;
 149         ///
 150         BitmapFile snippets;
 151         ///
 152         pid_t pid;
 153 };
 154
 155 typedef map<pid_t, InProgress>  InProgressProcesses;
 156
 157 typedef InProgressProcesses::value_type InProgressProcess;
 158
 159 } // namespace
 160
 161
 162 namespace lyx {
 163 namespace graphics {
 164
 165 class PreviewLoader::Impl {
 166 public:
 167         ///
 168         Impl(PreviewLoader & p, Buffer const & b);
 169         /// Stop any InProgress items still executing.
 170         ~Impl();
 171         ///
 172         PreviewImage const * preview(string const & latex_snippet) const;
 173         ///
 174         PreviewLoader::Status status(string const & latex_snippet) const;
 175         ///
 176         void add(string const & latex_snippet);
 177         ///
 178         void remove(string const & latex_snippet);
 179         /// \p wait whether to wait for the process to complete or, instead,
 180         /// to do it in the background.
 181         void startLoading(bool wait = false);
 182         ///
 183         void refreshPreviews();
 184
 185         /// Emit this signal when an image is ready for display.
 186         signals2::signal<void(PreviewImage const &)> imageReady;
 187
 188         Buffer const & buffer() const { return buffer_; }
 189
 190         lyx::Converter const * setConverter(string const & from);
 191
 192 private:
 193         /// Called by the ForkedCall process that generated the bitmap files.
 194         void finishedGenerating(pid_t, int);
 195         ///
 196         void dumpPreamble(otexstream &, OutputParams::FLAVOR) const;
 197         ///
 198         void dumpData(odocstream &, BitmapFile const &) const;
 199
 200         /** cache_ allows easy retrieval of already-generated images
 201          *  using the LaTeX snippet as the identifier.
 202          */
 203         typedef std::shared_ptr<PreviewImage> PreviewImagePtr;
 204         ///
 205         typedef map<string, PreviewImagePtr> Cache;
 206         ///
 207         Cache cache_;
 208
 209         /** pending_ stores the LaTeX snippets in anticipation of them being
 210          *  sent to the converter.
 211          */
 212         PendingSnippets pending_;
 213
 214         /** in_progress_ stores all forked processes so that we can proceed
 215          *  thereafter.
 216          */
 217         InProgressProcesses in_progress_;
 218
 219         ///
 220         PreviewLoader & parent_;
 221         ///
 222         Buffer const & buffer_;
 223         ///
 224         mutable int font_scaling_factor_;
 225         ///
 226         mutable int fg_color_;
 227         ///
 228         mutable int bg_color_;
 229         ///
 230         QTimer * delay_refresh_;
 231         ///
 232         Trackable trackable_;
 233         ///
 234         bool finished_generating_;
 235
 236         /// We don't own this
 237         static lyx::Converter const * pconverter_;
 238
 239 };
 240
 241
 242 lyx::Converter const * PreviewLoader::Impl::pconverter_;
 243
 244
 245 //
 246 // The public interface, defined in PreviewLoader.h
 247 //
 248
 249 PreviewLoader::PreviewLoader(Buffer const & b)
 250         : pimpl_(new Impl(*this, b))
 251 {}
 252
 253
 254 PreviewLoader::~PreviewLoader()
 255 {
 256         delete pimpl_;
 257 }
 258
 259
 260 PreviewImage const * PreviewLoader::preview(string const & latex_snippet) const
 261 {
 262         return pimpl_->preview(latex_snippet);
 263 }
 264
 265
 266 PreviewLoader::Status PreviewLoader::status(string const & latex_snippet) const
 267 {
 268         return pimpl_->status(latex_snippet);
 269 }
 270
 271
 272 void PreviewLoader::add(string const & latex_snippet) const
 273 {
 274         pimpl_->add(latex_snippet);
 275 }
 276
 277
 278 void PreviewLoader::remove(string const & latex_snippet) const
 279 {
 280         pimpl_->remove(latex_snippet);
 281 }
 282
 283
 284 void PreviewLoader::startLoading(bool wait) const
 285 {
 286         pimpl_->startLoading(wait);
 287 }
 288
 289
 290 void PreviewLoader::refreshPreviews()
 291 {
 292         pimpl_->refreshPreviews();
 293 }
 294
 295
 296 signals2::connection PreviewLoader::connect(slot const & slot) const
 297 {
 298         return pimpl_->imageReady.connect(slot);
 299 }
 300
 301
 302 void PreviewLoader::emitSignal(PreviewImage const & pimage) const
 303 {
 304         pimpl_->imageReady(pimage);
 305 }
 306
 307
 308 Buffer const & PreviewLoader::buffer() const
 309 {
 310         return pimpl_->buffer();
 311 }
 312
 313 } // namespace graphics
 314 } // namespace lyx
 315
 316
 317 // The details of the Impl
 318 // =======================
 319
 320 namespace {
 321
 322 std::function<SnippetPair (string const &)> IncrementedFileName
 323         (string const & to_format, string const & filename_base)
 324 {
 325         return [&to_format, &filename_base](string const & snippet)
 326         {
 327                 static int counter_ = 1;
 328                 ostringstream os;
 329                 os << filename_base << counter_++ << '.' << to_format;
 330                 string const file = os.str();
 331                 return make_pair(snippet, FileName(file));
 332         };
 333 }
 334
 335
 336 InProgress::InProgress(string const & filename_base,
 337                        PendingSnippets const & pending,
 338                        string const & to_format)
 339         : metrics_file(filename_base + ".metrics"),
 340           snippets(pending.size()), pid(0)
 341 {
 342         PendingSnippets::const_iterator pit  = pending.begin();
 343         PendingSnippets::const_iterator pend = pending.end();
 344         BitmapFile::iterator sit = snippets.begin();
 345
 346         transform(pit, pend, sit,
 347                        IncrementedFileName(to_format, filename_base));
 348 }
 349
 350
 351 void InProgress::stop() const
 352 {
 353         if (pid)
 354                 ForkedCallsController::kill(pid, 0);
 355
 356         if (!metrics_file.empty())
 357                 metrics_file.removeFile();
 358
 359         BitmapFile::const_iterator vit  = snippets.begin();
 360         BitmapFile::const_iterator vend = snippets.end();
 361         for (; vit != vend; ++vit) {
 362                 if (!vit->second.empty())
 363                         vit->second.removeFile();
 364         }
 365 }
 366
 367 } // namespace
 368
 369
 370 namespace lyx {
 371 namespace graphics {
 372
 373 PreviewLoader::Impl::Impl(PreviewLoader & p, Buffer const & b)
 374         : parent_(p), buffer_(b), finished_generating_(true)
 375 {
 376         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 377         if (theApp()) {
 378                 fg_color_ = convert(theApp()->hexName(foregroundColor()).c_str(), 16);
 379                 bg_color_ = convert(theApp()->hexName(backgroundColor()).c_str(), 16);
 380         } else {
 381                 fg_color_ = 0x0;
 382                 bg_color_ = 0xffffff;
 383         }
 384         if (!pconverter_)
 385                 pconverter_ = setConverter("lyxpreview");
 386
 387         delay_refresh_ = new QTimer(&parent_);
 388         delay_refresh_->setSingleShot(true);
 389         QObject::connect(delay_refresh_, SIGNAL(timeout()),
 390                          &parent_, SLOT(refreshPreviews()));
 391 }
 392
 393
 394 lyx::Converter const * PreviewLoader::Impl::setConverter(string const & from)
 395 {
 396         typedef vector<string> FmtList;
 397         FmtList const & loadableFormats = graphics::Cache::get().loadableFormats();
 398         FmtList::const_iterator it = loadableFormats.begin();
 399         FmtList::const_iterator const end = loadableFormats.end();
 400
 401         for (; it != end; ++it) {
 402                 string const to = *it;
 403                 if (from == to)
 404                         continue;
 405
 406                 lyx::Converter const * ptr = lyx::theConverters().getConverter(from, to);
 407                 if (ptr)
 408                         return ptr;
 409         }
 410
 411         // Show the error only once. This is thread-safe.
 412         static nullptr_t no_conv = [&]{
 413                 LYXERR0("PreviewLoader::startLoading()\n"
 414                         << "No converter from \"" << from
 415                         << "\" format has been defined.");
 416                 return nullptr;
 417         } ();
 418
 419         return no_conv;
 420 }
 421
 422
 423 PreviewLoader::Impl::~Impl()
 424 {
 425         delete delay_refresh_;
 426
 427         InProgressProcesses::iterator ipit  = in_progress_.begin();
 428         InProgressProcesses::iterator ipend = in_progress_.end();
 429
 430         for (; ipit != ipend; ++ipit)
 431                 ipit->second.stop();
 432 }
 433
 434
 435 PreviewImage const *
 436 PreviewLoader::Impl::preview(string const & latex_snippet) const
 437 {
 438         int fs = int(buffer_.fontScalingFactor());
 439         int fg = 0x0;
 440         int bg = 0xffffff;
 441         if (theApp()) {
 442                 fg = convert(theApp()->hexName(foregroundColor()).c_str(), 16);
 443                 bg = convert(theApp()->hexName(backgroundColor()).c_str(), 16);
 444         }
 445         if (font_scaling_factor_ != fs || fg_color_ != fg || bg_color_ != bg) {
 446                 // Schedule refresh of all previews on zoom or color changes.
 447                 // The previews are regenerated only after the zoom factor
 448                 // has not been changed for about 1 second.
 449                 fg_color_ = fg;
 450                 bg_color_ = bg;
 451                 delay_refresh_->start(1000);
 452         }
 453         // Don't try to access the cache until we are done.
 454         if (delay_refresh_->isActive() || !finished_generating_)
 455                 return nullptr;
 456
 457         Cache::const_iterator it = cache_.find(latex_snippet);
 458         return (it == cache_.end()) ? nullptr : it->second.get();
 459 }
 460
 461
 462 void PreviewLoader::Impl::refreshPreviews()
 463 {
 464         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 465         // Reschedule refresh until the previous process completed.
 466         if (!finished_generating_) {
 467                 delay_refresh_->start(1000);
 468                 return;
 469         }
 470         Cache::const_iterator cit = cache_.begin();
 471         Cache::const_iterator cend = cache_.end();
 472         while (cit != cend)
 473                 parent_.remove((cit++)->first);
 474         finished_generating_ = false;
 475         buffer_.updatePreviews();
 476 }
 477
 478
 479 namespace {
 480
 481 std::function<bool (InProgressProcess const &)> FindSnippet(string const & s)
 482 {
 483         return [&s](InProgressProcess const & process) {
 484                 BitmapFile const & snippets = process.second.snippets;
 485                 BitmapFile::const_iterator beg  = snippets.begin();
 486                 BitmapFile::const_iterator end = snippets.end();
 487                 return find_if(beg, end, FindFirst(s)) != end;
 488         };
 489 }
 490
 491 } // namespace
 492
 493 PreviewLoader::Status
 494 PreviewLoader::Impl::status(string const & latex_snippet) const
 495 {
 496         Cache::const_iterator cit = cache_.find(latex_snippet);
 497         if (cit != cache_.end())
 498                 return Ready;
 499
 500         PendingSnippets::const_iterator pit  = pending_.begin();
 501         PendingSnippets::const_iterator pend = pending_.end();
 502
 503         pit = find(pit, pend, latex_snippet);
 504         if (pit != pend)
 505                 return InQueue;
 506
 507         InProgressProcesses::const_iterator ipit  = in_progress_.begin();
 508         InProgressProcesses::const_iterator ipend = in_progress_.end();
 509
 510         ipit = find_if(ipit, ipend, FindSnippet(latex_snippet));
 511         if (ipit != ipend)
 512                 return Processing;
 513
 514         return NotFound;
 515 }
 516
 517
 518 void PreviewLoader::Impl::add(string const & latex_snippet)
 519 {
 520         if (!pconverter_ || status(latex_snippet) != NotFound)
 521                 return;
 522
 523         string const snippet = trim(latex_snippet);
 524         if (snippet.empty())
 525                 return;
 526
 527         LYXERR(Debug::GRAPHICS, "adding snippet:\n" << snippet);
 528
 529         pending_.push_back(snippet);
 530 }
 531
 532
 533 namespace {
 534
 535 std::function<void (InProgressProcess &)> EraseSnippet(string const & s) {
 536         return [&s](InProgressProcess & process) {
 537                 BitmapFile & snippets = process.second.snippets;
 538                 BitmapFile::iterator it  = snippets.begin();
 539                 BitmapFile::iterator end = snippets.end();
 540
 541                 it = find_if(it, end, FindFirst(s));
 542                 if (it != end)
 543                         snippets.erase(it, it+1);
 544         };
 545 };
 546
 547 } // namespace
 548
 549
 550 void PreviewLoader::Impl::remove(string const & latex_snippet)
 551 {
 552         Cache::iterator cit = cache_.find(latex_snippet);
 553         if (cit != cache_.end())
 554                 cache_.erase(cit);
 555
 556         PendingSnippets::iterator pit  = pending_.begin();
 557         PendingSnippets::iterator pend = pending_.end();
 558
 559         pending_.erase(std::remove(pit, pend, latex_snippet), pend);
 560
 561         InProgressProcesses::iterator ipit  = in_progress_.begin();
 562         InProgressProcesses::iterator ipend = in_progress_.end();
 563
 564         for_each(ipit, ipend, EraseSnippet(latex_snippet));
 565
 566         while (ipit != ipend) {
 567                 InProgressProcesses::iterator curr = ipit++;
 568                 if (curr->second.snippets.empty())
 569                         in_progress_.erase(curr);
 570         }
 571 }
 572
 573
 574 void PreviewLoader::Impl::startLoading(bool wait)
 575 {
 576         if (pending_.empty() || !pconverter_)
 577                 return;
 578
 579         // Only start the process off after the buffer is loaded from file.
 580         if (!buffer_.isFullyLoaded())
 581                 return;
 582
 583         LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()");
 584
 585         // As used by the LaTeX file and by the resulting image files
 586         FileName const directory(buffer_.temppath());
 587
 588         FileName const latexfile = unique_tex_filename(directory);
 589         string const filename_base = removeExtension(latexfile.absFileName());
 590
 591         // Create an InProgress instance to place in the map of all
 592         // such processes if it starts correctly.
 593         InProgress inprogress(filename_base, pending_, pconverter_->to());
 594
 595         // clear pending_, so we're ready to start afresh.
 596         pending_.clear();
 597
 598         // Output the LaTeX file.
 599         // we use the encoding of the buffer
 600         Encoding const & enc = buffer_.params().encoding();
 601         ofdocstream of;
 602         try { of.reset(enc.iconvName()); }
 603         catch (iconv_codecvt_facet_exception const & e) {
 604                 LYXERR0("Caught iconv exception: " << e.what()
 605                         << "\nUnable to create LaTeX file: " << latexfile);
 606                 return;
 607         }
 608
 609         otexstream os(of);
 610         OutputParams runparams(&enc);
 611         LaTeXFeatures features(buffer_, buffer_.params(), runparams);
 612
 613         if (!openFileWrite(of, latexfile))
 614                 return;
 615
 616         if (!of) {
 617                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 618                                         << "Unable to create LaTeX file\n" << latexfile);
 619                 return;
 620         }
 621         of << "\\batchmode\n";
 622
 623         // Set \jobname of previews to the document name (see bug 9627)
 624         of << "\\def\\jobname{"
 625            << from_utf8(changeExtension(buffer_.latexName(true), ""))
 626            << "}\n";
 627
 628         LYXERR(Debug::LATEX, "Format = " << buffer_.params().getDefaultOutputFormat());
 629         string latexparam = "";
 630         bool docformat = !buffer_.params().default_output_format.empty()
 631                         && buffer_.params().default_output_format != "default";
 632         // Use LATEX flavor if the document does not specify a specific
 633         // output format (see bug 9371).
 634         OutputParams::FLAVOR flavor = docformat
 635                                         ? buffer_.params().getOutputFlavor()
 636                                         : OutputParams::LATEX;
 637         if (buffer_.params().encoding().package() == Encoding::japanese) {
 638                 latexparam = " --latex=platex";
 639                 flavor = OutputParams::LATEX;
 640         }
 641         else if (buffer_.params().useNonTeXFonts) {
 642                 if (flavor == OutputParams::LUATEX)
 643                         latexparam = " --latex=lualatex";
 644                 else {
 645                         flavor = OutputParams::XETEX;
 646                         latexparam = " --latex=xelatex";
 647                 }
 648         }
 649         else {
 650                 switch (flavor) {
 651                         case OutputParams::PDFLATEX:
 652                                 latexparam = " --latex=pdflatex";
 653                                 break;
 654                         case OutputParams::XETEX:
 655                                 latexparam = " --latex=xelatex";
 656                                 break;
 657                         case OutputParams::LUATEX:
 658                                 latexparam = " --latex=lualatex";
 659                                 break;
 660                         case OutputParams::DVILUATEX:
 661                                 latexparam = " --latex=dvilualatex";
 662                                 break;
 663                         default:
 664                                 flavor = OutputParams::LATEX;
 665                 }
 666         }
 667         dumpPreamble(os, flavor);
 668         // handle inputenc etc.
 669         // I think this is already handled by dumpPreamble(): Kornel
 670         // buffer_.params().writeEncodingPreamble(os, features);
 671         of << "\n\\begin{document}\n";
 672         dumpData(of, inprogress.snippets);
 673         of << "\n\\end{document}\n";
 674         of.close();
 675         if (of.fail()) {
 676                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 677                                          << "File was not closed properly.");
 678                 return;
 679         }
 680
 681         // The conversion command.
 682         ostringstream cs;
 683         cs << pconverter_->command()
 684            << " " << quoteName(latexfile.toFilesystemEncoding())
 685            << " --dpi " << font_scaling_factor_;
 686
 687         // FIXME XHTML
 688         // The colors should be customizable.
 689         if (!buffer_.isExporting()) {
 690                 ColorCode const fg = PreviewLoader::foregroundColor();
 691                 ColorCode const bg = PreviewLoader::backgroundColor();
 692                 cs << " --fg " << theApp()->hexName(fg)
 693                    << " --bg " << theApp()->hexName(bg);
 694         }
 695
 696         cs << latexparam;
 697         cs << " --bibtex=" << quoteName(buffer_.params().bibtexCommand());
 698         if (buffer_.params().bufferFormat() == "lilypond-book")
 699                 cs << " --lilypond";
 700
 701         string const command = cs.str();
 702
 703         if (wait) {
 704                 ForkedCall call(buffer_.filePath(), buffer_.layoutPos());
 705                 int ret = call.startScript(ForkedProcess::Wait, command);
 706                 // PID_MAX_LIMIT is 2^22 so we start one after that
 707                 static atomic_int fake((1 << 22) + 1);
 708                 int pid = fake++;
 709                 inprogress.pid = pid;
 710                 inprogress.command = command;
 711                 in_progress_[pid] = inprogress;
 712                 finishedGenerating(pid, ret);
 713                 return;
 714         }
 715
 716         // Initiate the conversion from LaTeX to bitmap images files.
 717         ForkedCall::sigPtr convert_ptr = make_shared<ForkedCall::sig>();
 718         convert_ptr->connect(ForkedProcess::slot([this](pid_t pid, int retval){
 719                                 finishedGenerating(pid, retval);
 720                         }).track_foreign(trackable_.p()));
 721
 722         ForkedCall call(buffer_.filePath());
 723         int ret = call.startScript(command, convert_ptr);
 724
 725         if (ret != 0) {
 726                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 727                                         << "Unable to start process\n" << command);
 728                 return;
 729         }
 730
 731         // Store the generation process in a list of all such processes
 732         inprogress.pid = call.pid();
 733         inprogress.command = command;
 734         in_progress_[inprogress.pid] = inprogress;
 735 }
 736
 737
 738 double PreviewLoader::displayPixelRatio() const
 739 {
 740         return buffer().params().display_pixel_ratio;
 741 }
 742
 743 void PreviewLoader::Impl::finishedGenerating(pid_t pid, int retval)
 744 {
 745         // Paranoia check!
 746         InProgressProcesses::iterator git = in_progress_.find(pid);
 747         if (git == in_progress_.end()) {
 748                 lyxerr << "PreviewLoader::finishedGenerating(): unable to find "
 749                         "data for PID " << pid << endl;
 750                 finished_generating_ = true;
 751                 return;
 752         }
 753
 754         string const command = git->second.command;
 755         string const status = retval > 0 ? "failed" : "succeeded";
 756         LYXERR(Debug::GRAPHICS, "PreviewLoader::finishedInProgress("
 757                                 << retval << "): processing " << status
 758                                 << " for " << command);
 759         if (retval > 0) {
 760                 in_progress_.erase(git);
 761                 finished_generating_ = true;
 762                 return;
 763         }
 764
 765         // Read the metrics file, if it exists
 766         vector<double> ascent_fractions(git->second.snippets.size());
 767         setAscentFractions(ascent_fractions, git->second.metrics_file);
 768
 769         // Add these newly generated bitmap files to the cache and
 770         // start loading them into LyX.
 771         BitmapFile::const_iterator it  = git->second.snippets.begin();
 772         BitmapFile::const_iterator end = git->second.snippets.end();
 773
 774         list<PreviewImagePtr> newimages;
 775
 776         size_t metrics_counter = 0;
 777         for (; it != end; ++it, ++metrics_counter) {
 778                 string const & snip = it->first;
 779                 FileName const & file = it->second;
 780                 double af = ascent_fractions[metrics_counter];
 781
 782                 // Add the image to the cache only if it's actually present
 783                 // and not empty (an empty image is signaled by af < 0)
 784                 if (af >= 0 && file.isReadableFile()) {
 785                         PreviewImagePtr ptr(new PreviewImage(parent_, snip, file, af));
 786                         cache_[snip] = ptr;
 787
 788                         newimages.push_back(ptr);
 789                 }
 790
 791         }
 792
 793         // Remove the item from the list of still-executing processes.
 794         in_progress_.erase(git);
 795
 796         // Tell the outside world
 797         list<PreviewImagePtr>::const_reverse_iterator
 798                 nit  = newimages.rbegin();
 799         list<PreviewImagePtr>::const_reverse_iterator
 800                 nend = newimages.rend();
 801         for (; nit != nend; ++nit) {
 802                 imageReady(*nit->get());
 803         }
 804         finished_generating_ = true;
 805 }
 806
 807
 808 void PreviewLoader::Impl::dumpPreamble(otexstream & os, OutputParams::FLAVOR flavor) const
 809 {
 810         // Dump the preamble only.
 811         LYXERR(Debug::LATEX, "dumpPreamble, flavor == " << flavor);
 812         OutputParams runparams(&buffer_.params().encoding());
 813         runparams.flavor = flavor;
 814         runparams.nice = true;
 815         runparams.moving_arg = true;
 816         runparams.free_spacing = true;
 817         runparams.is_child = buffer_.parent();
 818         buffer_.writeLaTeXSource(os, buffer_.filePath(), runparams, Buffer::OnlyPreamble);
 819
 820         // FIXME! This is a HACK! The proper fix is to control the 'true'
 821         // passed to WriteStream below:
 822         // int InsetMathNest::latex(Buffer const &, odocstream & os,
 823         //                          OutputParams const & runparams) const
 824         // {
 825         //      WriteStream wi(os, runparams.moving_arg, true);
 826         //      par_->write(wi);
 827         //      return wi.line();
 828         // }
 829         os << "\n"
 830            << "\\def\\lyxlock{}\n"
 831            << "\n";
 832
 833         // All equation labels appear as "(#)" + preview.sty's rendering of
 834         // the label name
 835         if (lyxrc.preview_hashed_labels)
 836                 os << "\\renewcommand{\\theequation}{\\#}\n";
 837
 838         // Use the preview style file to ensure that each snippet appears on a
 839         // fresh page.
 840         // Also support PDF output (automatically generated e.g. when
 841         // \usepackage[pdftex]{hyperref} is used and XeTeX.
 842         os << "\n"
 843            << "\\usepackage[active,delayed,showlabels,lyx]{preview}\n"
 844            << "\n";
 845 }
 846
 847
 848 void PreviewLoader::Impl::dumpData(odocstream & os,
 849                                    BitmapFile const & vec) const
 850 {
 851         if (vec.empty())
 852                 return;
 853
 854         BitmapFile::const_iterator it  = vec.begin();
 855         BitmapFile::const_iterator end = vec.end();
 856
 857         for (; it != end; ++it) {
 858                 // FIXME UNICODE
 859                 os << "\\begin{preview}\n"
 860                    << from_utf8(it->first)
 861                    << "\n\\end{preview}\n\n";
 862         }
 863 }
 864
 865 } // namespace graphics
 866 } // namespace lyx
 867
 868 #include "moc_PreviewLoader.cpp"