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         bool finished_generating_;
 233
 234         /// We don't own this
 235         static lyx::Converter const * pconverter_;
 236
 237         Trackable trackable_;
 238 };
 239
 240
 241 lyx::Converter const * PreviewLoader::Impl::pconverter_;
 242
 243
 244 //
 245 // The public interface, defined in PreviewLoader.h
 246 //
 247
 248 PreviewLoader::PreviewLoader(Buffer const & b)
 249         : pimpl_(new Impl(*this, b))
 250 {}
 251
 252
 253 PreviewLoader::~PreviewLoader()
 254 {
 255         delete pimpl_;
 256 }
 257
 258
 259 PreviewImage const * PreviewLoader::preview(string const & latex_snippet) const
 260 {
 261         return pimpl_->preview(latex_snippet);
 262 }
 263
 264
 265 PreviewLoader::Status PreviewLoader::status(string const & latex_snippet) const
 266 {
 267         return pimpl_->status(latex_snippet);
 268 }
 269
 270
 271 void PreviewLoader::add(string const & latex_snippet) const
 272 {
 273         pimpl_->add(latex_snippet);
 274 }
 275
 276
 277 void PreviewLoader::remove(string const & latex_snippet) const
 278 {
 279         pimpl_->remove(latex_snippet);
 280 }
 281
 282
 283 void PreviewLoader::startLoading(bool wait) const
 284 {
 285         pimpl_->startLoading(wait);
 286 }
 287
 288
 289 void PreviewLoader::refreshPreviews()
 290 {
 291         pimpl_->refreshPreviews();
 292 }
 293
 294
 295 signals2::connection PreviewLoader::connect(slot const & slot) const
 296 {
 297         return pimpl_->imageReady.connect(slot);
 298 }
 299
 300
 301 void PreviewLoader::emitSignal(PreviewImage const & pimage) const
 302 {
 303         pimpl_->imageReady(pimage);
 304 }
 305
 306
 307 Buffer const & PreviewLoader::buffer() const
 308 {
 309         return pimpl_->buffer();
 310 }
 311
 312 } // namespace graphics
 313 } // namespace lyx
 314
 315
 316 // The details of the Impl
 317 // =======================
 318
 319 namespace {
 320
 321 std::function<SnippetPair (string const &)> IncrementedFileName
 322         (string const & to_format, string const & filename_base)
 323 {
 324         return [&to_format, &filename_base](string const & snippet)
 325         {
 326                 static int counter_ = 1;
 327                 ostringstream os;
 328                 os << filename_base << counter_++ << '.' << to_format;
 329                 string const file = os.str();
 330                 return make_pair(snippet, FileName(file));
 331         };
 332 }
 333
 334
 335 InProgress::InProgress(string const & filename_base,
 336                        PendingSnippets const & pending,
 337                        string const & to_format)
 338         : metrics_file(filename_base + ".metrics"),
 339           snippets(pending.size()), pid(0)
 340 {
 341         PendingSnippets::const_iterator pit  = pending.begin();
 342         PendingSnippets::const_iterator pend = pending.end();
 343         BitmapFile::iterator sit = snippets.begin();
 344
 345         transform(pit, pend, sit,
 346                        IncrementedFileName(to_format, filename_base));
 347 }
 348
 349
 350 void InProgress::stop() const
 351 {
 352         if (pid)
 353                 ForkedCallsController::kill(pid, 0);
 354
 355         if (!metrics_file.empty())
 356                 metrics_file.removeFile();
 357
 358         BitmapFile::const_iterator vit  = snippets.begin();
 359         BitmapFile::const_iterator vend = snippets.end();
 360         for (; vit != vend; ++vit) {
 361                 if (!vit->second.empty())
 362                         vit->second.removeFile();
 363         }
 364 }
 365
 366 } // namespace
 367
 368
 369 namespace lyx {
 370 namespace graphics {
 371
 372 PreviewLoader::Impl::Impl(PreviewLoader & p, Buffer const & b)
 373         : parent_(p), buffer_(b), finished_generating_(true)
 374 {
 375         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 376         if (theApp()) {
 377                 fg_color_ = strtol(theApp()->hexName(foregroundColor()).c_str(), nullptr, 16);
 378                 bg_color_ = strtol(theApp()->hexName(backgroundColor()).c_str(), nullptr, 16);
 379         } else {
 380                 fg_color_ = 0x0;
 381                 bg_color_ = 0xffffff;
 382         }
 383         if (!pconverter_)
 384                 pconverter_ = setConverter("lyxpreview");
 385
 386         delay_refresh_ = new QTimer(&parent_);
 387         delay_refresh_->setSingleShot(true);
 388         QObject::connect(delay_refresh_, SIGNAL(timeout()),
 389                          &parent_, SLOT(refreshPreviews()));
 390 }
 391
 392
 393 lyx::Converter const * PreviewLoader::Impl::setConverter(string const & from)
 394 {
 395         typedef vector<string> FmtList;
 396         FmtList const & loadableFormats = graphics::Cache::get().loadableFormats();
 397         FmtList::const_iterator it = loadableFormats.begin();
 398         FmtList::const_iterator const end = loadableFormats.end();
 399
 400         for (; it != end; ++it) {
 401                 string const to = *it;
 402                 if (from == to)
 403                         continue;
 404
 405                 lyx::Converter const * ptr = lyx::theConverters().getConverter(from, to);
 406                 if (ptr)
 407                         return ptr;
 408         }
 409
 410         // Show the error only once. This is thread-safe.
 411         static nullptr_t no_conv = [&]{
 412                 LYXERR0("PreviewLoader::startLoading()\n"
 413                         << "No converter from \"" << from
 414                         << "\" format has been defined.");
 415                 return nullptr;
 416         } ();
 417
 418         return no_conv;
 419 }
 420
 421
 422 PreviewLoader::Impl::~Impl()
 423 {
 424         delete delay_refresh_;
 425
 426         InProgressProcesses::iterator ipit  = in_progress_.begin();
 427         InProgressProcesses::iterator ipend = in_progress_.end();
 428
 429         for (; ipit != ipend; ++ipit)
 430                 ipit->second.stop();
 431 }
 432
 433
 434 PreviewImage const *
 435 PreviewLoader::Impl::preview(string const & latex_snippet) const
 436 {
 437         int fs = int(buffer_.fontScalingFactor());
 438         int fg = 0x0;
 439         int bg = 0xffffff;
 440         if (theApp()) {
 441                 fg = strtol(theApp()->hexName(foregroundColor()).c_str(), nullptr, 16);
 442                 bg = strtol(theApp()->hexName(backgroundColor()).c_str(), nullptr, 16);
 443         }
 444         if (font_scaling_factor_ != fs || fg_color_ != fg || bg_color_ != bg) {
 445                 // Schedule refresh of all previews on zoom or color changes.
 446                 // The previews are regenerated only after the zoom factor
 447                 // has not been changed for about 1 second.
 448                 fg_color_ = fg;
 449                 bg_color_ = bg;
 450                 delay_refresh_->start(1000);
 451         }
 452         // Don't try to access the cache until we are done.
 453         if (delay_refresh_->isActive() || !finished_generating_)
 454                 return nullptr;
 455         Cache::const_iterator it = cache_.find(latex_snippet);
 456         return (it == cache_.end()) ? nullptr : it->second.get();
 457 }
 458
 459
 460 void PreviewLoader::Impl::refreshPreviews()
 461 {
 462         font_scaling_factor_ = int(buffer_.fontScalingFactor());
 463         // Reschedule refresh until the previous process completed.
 464         if (!finished_generating_) {
 465                 delay_refresh_->start(1000);
 466                 return;
 467         }
 468         Cache::const_iterator cit = cache_.begin();
 469         Cache::const_iterator cend = cache_.end();
 470         while (cit != cend)
 471                 parent_.remove((cit++)->first);
 472         finished_generating_ = false;
 473         buffer_.updatePreviews();
 474 }
 475
 476
 477 namespace {
 478
 479 std::function<bool (InProgressProcess const &)> FindSnippet(string const & s)
 480 {
 481         return [&s](InProgressProcess const & process) {
 482                 BitmapFile const & snippets = process.second.snippets;
 483                 BitmapFile::const_iterator beg  = snippets.begin();
 484                 BitmapFile::const_iterator end = snippets.end();
 485                 return find_if(beg, end, FindFirst(s)) != end;
 486         };
 487 }
 488
 489 } // namespace
 490
 491 PreviewLoader::Status
 492 PreviewLoader::Impl::status(string const & latex_snippet) const
 493 {
 494         Cache::const_iterator cit = cache_.find(latex_snippet);
 495         if (cit != cache_.end())
 496                 return Ready;
 497
 498         PendingSnippets::const_iterator pit  = pending_.begin();
 499         PendingSnippets::const_iterator pend = pending_.end();
 500
 501         pit = find(pit, pend, latex_snippet);
 502         if (pit != pend)
 503                 return InQueue;
 504
 505         InProgressProcesses::const_iterator ipit  = in_progress_.begin();
 506         InProgressProcesses::const_iterator ipend = in_progress_.end();
 507
 508         ipit = find_if(ipit, ipend, FindSnippet(latex_snippet));
 509         if (ipit != ipend)
 510                 return Processing;
 511
 512         return NotFound;
 513 }
 514
 515
 516 void PreviewLoader::Impl::add(string const & latex_snippet)
 517 {
 518         if (!pconverter_ || status(latex_snippet) != NotFound)
 519                 return;
 520
 521         string const snippet = trim(latex_snippet);
 522         if (snippet.empty())
 523                 return;
 524
 525         LYXERR(Debug::GRAPHICS, "adding snippet:\n" << snippet);
 526
 527         pending_.push_back(snippet);
 528 }
 529
 530
 531 namespace {
 532
 533 std::function<void (InProgressProcess &)> EraseSnippet(string const & s) {
 534         return [&s](InProgressProcess & process) {
 535                 BitmapFile & snippets = process.second.snippets;
 536                 BitmapFile::iterator it  = snippets.begin();
 537                 BitmapFile::iterator end = snippets.end();
 538
 539                 it = find_if(it, end, FindFirst(s));
 540                 if (it != end)
 541                         snippets.erase(it, it+1);
 542         };
 543 };
 544
 545 } // namespace
 546
 547
 548 void PreviewLoader::Impl::remove(string const & latex_snippet)
 549 {
 550         Cache::iterator cit = cache_.find(latex_snippet);
 551         if (cit != cache_.end())
 552                 cache_.erase(cit);
 553
 554         PendingSnippets::iterator pit  = pending_.begin();
 555         PendingSnippets::iterator pend = pending_.end();
 556
 557         pending_.erase(std::remove(pit, pend, latex_snippet), pend);
 558
 559         InProgressProcesses::iterator ipit  = in_progress_.begin();
 560         InProgressProcesses::iterator ipend = in_progress_.end();
 561
 562         for_each(ipit, ipend, EraseSnippet(latex_snippet));
 563
 564         while (ipit != ipend) {
 565                 InProgressProcesses::iterator curr = ipit++;
 566                 if (curr->second.snippets.empty())
 567                         in_progress_.erase(curr);
 568         }
 569 }
 570
 571
 572 void PreviewLoader::Impl::startLoading(bool wait)
 573 {
 574         if (pending_.empty() || !pconverter_)
 575                 return;
 576
 577         // Only start the process off after the buffer is loaded from file.
 578         if (!buffer_.isFullyLoaded())
 579                 return;
 580
 581         LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()");
 582
 583         // As used by the LaTeX file and by the resulting image files
 584         FileName const directory(buffer_.temppath());
 585
 586         FileName const latexfile = unique_tex_filename(directory);
 587         string const filename_base = removeExtension(latexfile.absFileName());
 588
 589         // Create an InProgress instance to place in the map of all
 590         // such processes if it starts correctly.
 591         InProgress inprogress(filename_base, pending_, pconverter_->to());
 592
 593         // clear pending_, so we're ready to start afresh.
 594         pending_.clear();
 595
 596         // Output the LaTeX file.
 597         // we use the encoding of the buffer
 598         Encoding const & enc = buffer_.params().encoding();
 599         ofdocstream of;
 600         try { of.reset(enc.iconvName()); }
 601         catch (iconv_codecvt_facet_exception const & e) {
 602                 LYXERR0("Caught iconv exception: " << e.what()
 603                         << "\nUnable to create LaTeX file: " << latexfile);
 604                 return;
 605         }
 606
 607         otexstream os(of);
 608         OutputParams runparams(&enc);
 609         LaTeXFeatures features(buffer_, buffer_.params(), runparams);
 610
 611         if (!openFileWrite(of, latexfile))
 612                 return;
 613
 614         if (!of) {
 615                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 616                                         << "Unable to create LaTeX file\n" << latexfile);
 617                 return;
 618         }
 619         of << "\\batchmode\n";
 620
 621         // Set \jobname of previews to the document name (see bug 9627)
 622         of << "\\def\\jobname{"
 623            << from_utf8(changeExtension(buffer_.latexName(true), ""))
 624            << "}\n";
 625
 626         LYXERR(Debug::LATEX, "Format = " << buffer_.params().getDefaultOutputFormat());
 627         string latexparam = "";
 628         bool docformat = !buffer_.params().default_output_format.empty()
 629                         && buffer_.params().default_output_format != "default";
 630         // Use LATEX flavor if the document does not specify a specific
 631         // output format (see bug 9371).
 632         OutputParams::FLAVOR flavor = docformat
 633                                         ? buffer_.params().getOutputFlavor()
 634                                         : OutputParams::LATEX;
 635         if (buffer_.params().encoding().package() == Encoding::japanese) {
 636                 latexparam = " --latex=platex";
 637                 flavor = OutputParams::LATEX;
 638         }
 639         else if (buffer_.params().useNonTeXFonts) {
 640                 if (flavor == OutputParams::LUATEX)
 641                         latexparam = " --latex=lualatex";
 642                 else {
 643                         flavor = OutputParams::XETEX;
 644                         latexparam = " --latex=xelatex";
 645                 }
 646         }
 647         else {
 648                 switch (flavor) {
 649                         case OutputParams::PDFLATEX:
 650                                 latexparam = " --latex=pdflatex";
 651                                 break;
 652                         case OutputParams::XETEX:
 653                                 latexparam = " --latex=xelatex";
 654                                 break;
 655                         case OutputParams::LUATEX:
 656                                 latexparam = " --latex=lualatex";
 657                                 break;
 658                         case OutputParams::DVILUATEX:
 659                                 latexparam = " --latex=dvilualatex";
 660                                 break;
 661                         default:
 662                                 flavor = OutputParams::LATEX;
 663                 }
 664         }
 665         dumpPreamble(os, flavor);
 666         // handle inputenc etc.
 667         // I think this is already handled by dumpPreamble(): Kornel
 668         // buffer_.params().writeEncodingPreamble(os, features);
 669         of << "\n\\begin{document}\n";
 670         dumpData(of, inprogress.snippets);
 671         of << "\n\\end{document}\n";
 672         of.close();
 673         if (of.fail()) {
 674                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 675                                          << "File was not closed properly.");
 676                 return;
 677         }
 678
 679         // The conversion command.
 680         ostringstream cs;
 681         cs << pconverter_->command()
 682            << " " << quoteName(latexfile.toFilesystemEncoding())
 683            << " --dpi " << font_scaling_factor_;
 684
 685         // FIXME XHTML
 686         // The colors should be customizable.
 687         if (!buffer_.isExporting()) {
 688                 ColorCode const fg = PreviewLoader::foregroundColor();
 689                 ColorCode const bg = PreviewLoader::backgroundColor();
 690                 cs << " --fg " << theApp()->hexName(fg)
 691                    << " --bg " << theApp()->hexName(bg);
 692         }
 693
 694         cs << latexparam;
 695         cs << " --bibtex=" << quoteName(buffer_.params().bibtexCommand());
 696         if (buffer_.params().bufferFormat() == "lilypond-book")
 697                 cs << " --lilypond";
 698
 699         string const command = cs.str();
 700
 701         if (wait) {
 702                 ForkedCall call(buffer_.filePath(), buffer_.layoutPos());
 703                 int ret = call.startScript(ForkedProcess::Wait, command);
 704                 // PID_MAX_LIMIT is 2^22 so we start one after that
 705                 static atomic_int fake((1 << 22) + 1);
 706                 int pid = fake++;
 707                 inprogress.pid = pid;
 708                 inprogress.command = command;
 709                 in_progress_[pid] = inprogress;
 710                 finishedGenerating(pid, ret);
 711                 return;
 712         }
 713
 714         // Initiate the conversion from LaTeX to bitmap images files.
 715         ForkedCall::sigPtr convert_ptr = make_shared<ForkedCall::sig>();
 716         convert_ptr->connect(ForkedProcess::slot([this](pid_t pid, int retval){
 717                                 finishedGenerating(pid, retval);
 718                         }).track_foreign(trackable_.p()));
 719
 720         ForkedCall call(buffer_.filePath());
 721         int ret = call.startScript(command, convert_ptr);
 722
 723         if (ret != 0) {
 724                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 725                                         << "Unable to start process\n" << command);
 726                 return;
 727         }
 728
 729         // Store the generation process in a list of all such processes
 730         inprogress.pid = call.pid();
 731         inprogress.command = command;
 732         in_progress_[inprogress.pid] = inprogress;
 733 }
 734
 735
 736 double PreviewLoader::displayPixelRatio() const
 737 {
 738         return buffer().params().display_pixel_ratio;
 739 }
 740
 741 void PreviewLoader::Impl::finishedGenerating(pid_t pid, int retval)
 742 {
 743         // Paranoia check!
 744         InProgressProcesses::iterator git = in_progress_.find(pid);
 745         if (git == in_progress_.end()) {
 746                 lyxerr << "PreviewLoader::finishedGenerating(): unable to find "
 747                         "data for PID " << pid << endl;
 748                 finished_generating_ = true;
 749                 return;
 750         }
 751
 752         string const command = git->second.command;
 753         string const status = retval > 0 ? "failed" : "succeeded";
 754         LYXERR(Debug::GRAPHICS, "PreviewLoader::finishedInProgress("
 755                                 << retval << "): processing " << status
 756                                 << " for " << command);
 757         if (retval > 0) {
 758                 in_progress_.erase(git);
 759                 finished_generating_ = true;
 760                 return;
 761         }
 762
 763         // Read the metrics file, if it exists
 764         vector<double> ascent_fractions(git->second.snippets.size());
 765         setAscentFractions(ascent_fractions, git->second.metrics_file);
 766
 767         // Add these newly generated bitmap files to the cache and
 768         // start loading them into LyX.
 769         BitmapFile::const_iterator it  = git->second.snippets.begin();
 770         BitmapFile::const_iterator end = git->second.snippets.end();
 771
 772         list<PreviewImagePtr> newimages;
 773
 774         size_t metrics_counter = 0;
 775         for (; it != end; ++it, ++metrics_counter) {
 776                 string const & snip = it->first;
 777                 FileName const & file = it->second;
 778                 double af = ascent_fractions[metrics_counter];
 779
 780                 // Add the image to the cache only if it's actually present
 781                 // and not empty (an empty image is signaled by af < 0)
 782                 if (af >= 0 && file.isReadableFile()) {
 783                         PreviewImagePtr ptr(new PreviewImage(parent_, snip, file, af));
 784                         cache_[snip] = ptr;
 785
 786                         newimages.push_back(ptr);
 787                 }
 788
 789         }
 790
 791         // Remove the item from the list of still-executing processes.
 792         in_progress_.erase(git);
 793
 794         // Tell the outside world
 795         list<PreviewImagePtr>::const_reverse_iterator
 796                 nit  = newimages.rbegin();
 797         list<PreviewImagePtr>::const_reverse_iterator
 798                 nend = newimages.rend();
 799         for (; nit != nend; ++nit) {
 800                 imageReady(*nit->get());
 801         }
 802         finished_generating_ = true;
 803 }
 804
 805
 806 void PreviewLoader::Impl::dumpPreamble(otexstream & os, OutputParams::FLAVOR flavor) const
 807 {
 808         // Dump the preamble only.
 809         LYXERR(Debug::LATEX, "dumpPreamble, flavor == " << flavor);
 810         OutputParams runparams(&buffer_.params().encoding());
 811         runparams.flavor = flavor;
 812         runparams.nice = true;
 813         runparams.moving_arg = true;
 814         runparams.free_spacing = true;
 815         runparams.is_child = buffer_.parent();
 816         buffer_.writeLaTeXSource(os, buffer_.filePath(), runparams, Buffer::OnlyPreamble);
 817
 818         // FIXME! This is a HACK! The proper fix is to control the 'true'
 819         // passed to WriteStream below:
 820         // int InsetMathNest::latex(Buffer const &, odocstream & os,
 821         //                          OutputParams const & runparams) const
 822         // {
 823         //      WriteStream wi(os, runparams.moving_arg, true);
 824         //      par_->write(wi);
 825         //      return wi.line();
 826         // }
 827         os << "\n"
 828            << "\\def\\lyxlock{}\n"
 829            << "\n";
 830
 831         // All equation labels appear as "(#)" + preview.sty's rendering of
 832         // the label name
 833         if (lyxrc.preview_hashed_labels)
 834                 os << "\\renewcommand{\\theequation}{\\#}\n";
 835
 836         // Use the preview style file to ensure that each snippet appears on a
 837         // fresh page.
 838         // Also support PDF output (automatically generated e.g. when
 839         // \usepackage[pdftex]{hyperref} is used and XeTeX.
 840         os << "\n"
 841            << "\\usepackage[active,delayed,showlabels,lyx]{preview}\n"
 842            << "\n";
 843 }
 844
 845
 846 void PreviewLoader::Impl::dumpData(odocstream & os,
 847                                    BitmapFile const & vec) const
 848 {
 849         if (vec.empty())
 850                 return;
 851
 852         BitmapFile::const_iterator it  = vec.begin();
 853         BitmapFile::const_iterator end = vec.end();
 854
 855         for (; it != end; ++it) {
 856                 // FIXME UNICODE
 857                 os << "\\begin{preview}\n"
 858                    << from_utf8(it->first)
 859                    << "\n\\end{preview}\n\n";
 860         }
 861 }
 862
 863 } // namespace graphics
 864 } // namespace lyx
 865
 866 #include "moc_PreviewLoader.cpp"