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
  29 #include "frontends/Application.h" // hexName
  30
  31 #include "insets/Inset.h"
  32
  33 #include "support/convert.h"
  34 #include "support/debug.h"
  35 #include "support/FileName.h"
  36 #include "support/filetools.h"
  37 #include "support/ForkedCalls.h"
  38 #include "support/lstrings.h"
  39
  40 #include <boost/bind.hpp>
  41
  42 #include <sstream>
  43 #include <fstream>
  44 #include <iomanip>
  45
  46 using namespace std;
  47 using namespace lyx::support;
  48
  49 using boost::bind;
  50
  51 namespace {
  52
  53 typedef pair<string, FileName> SnippetPair;
  54
  55 // A list of all snippets to be converted to previews
  56 typedef list<string> PendingSnippets;
  57
  58 // Each item in the vector is a pair<snippet, image file name>.
  59 typedef vector<SnippetPair> BitmapFile;
  60
  61
  62 string const unique_filename(string const & bufferpath)
  63 {
  64         static int theCounter = 0;
  65         string const filename = lyx::convert<string>(theCounter++) + "lyxpreview";
  66         return addName(bufferpath, filename);
  67 }
  68
  69
  70 lyx::Converter const * setConverter(string const from)
  71 {
  72         typedef vector<string> FmtList;
  73         typedef lyx::graphics::Cache GCache;
  74         FmtList const & loadableFormats = GCache::get().loadableFormats();
  75         FmtList::const_iterator it = loadableFormats.begin();
  76         FmtList::const_iterator const end = loadableFormats.end();
  77
  78         for (; it != end; ++it) {
  79                 string const to = *it;
  80                 if (from == to)
  81                         continue;
  82
  83                 lyx::Converter const * ptr = lyx::theConverters().getConverter(from, to);
  84                 if (ptr)
  85                         return ptr;
  86         }
  87
  88         static bool first = true;
  89         if (first) {
  90                 first = false;
  91                 LYXERR0("PreviewLoader::startLoading()\n"
  92                   << "No converter from \"lyxpreview\" format has been defined.");
  93         }
  94         return 0;
  95 }
  96
  97
  98 void setAscentFractions(vector<double> & ascent_fractions,
  99                         FileName const & metrics_file)
 100 {
 101         // If all else fails, then the images will have equal ascents and
 102         // descents.
 103         vector<double>::iterator it  = ascent_fractions.begin();
 104         vector<double>::iterator end = ascent_fractions.end();
 105         fill(it, end, 0.5);
 106
 107         ifstream in(metrics_file.toFilesystemEncoding().c_str());
 108         if (!in.good()) {
 109                 LYXERR(lyx::Debug::GRAPHICS, "setAscentFractions(" << metrics_file << ")\n"
 110                         << "Unable to open file!");
 111                 return;
 112         }
 113
 114         bool error = false;
 115
 116         int snippet_counter = 1;
 117         while (!in.eof() && it != end) {
 118                 string snippet;
 119                 int id;
 120                 double ascent_fraction;
 121
 122                 in >> snippet >> id >> ascent_fraction;
 123
 124                 if (!in.good())
 125                         // eof after all
 126                         break;
 127
 128                 error = snippet != "Snippet";
 129                 if (error)
 130                         break;
 131
 132                 error = id != snippet_counter;
 133                 if (error)
 134                         break;
 135
 136                 *it = ascent_fraction;
 137
 138                 ++snippet_counter;
 139                 ++it;
 140         }
 141
 142         if (error) {
 143                 LYXERR(lyx::Debug::GRAPHICS, "setAscentFractions(" << metrics_file << ")\n"
 144                         << "Error reading file!\n");
 145         }
 146 }
 147
 148
 149 class FindFirst
 150 {
 151 public:
 152         FindFirst(string const & comp) : comp_(comp) {}
 153         bool operator()(SnippetPair const & sp) const { return sp.first == comp_; }
 154 private:
 155         string const comp_;
 156 };
 157
 158
 159 /// Store info on a currently executing, forked process.
 160 class InProgress {
 161 public:
 162         ///
 163         InProgress() : pid(0) {}
 164         ///
 165         InProgress(string const & filename_base,
 166                    PendingSnippets const & pending,
 167                    string const & to_format);
 168         /// Remove any files left lying around and kill the forked process.
 169         void stop() const;
 170
 171         ///
 172         pid_t pid;
 173         ///
 174         string command;
 175         ///
 176         FileName metrics_file;
 177         ///
 178         BitmapFile snippets;
 179 };
 180
 181 typedef map<pid_t, InProgress>  InProgressProcesses;
 182
 183 typedef InProgressProcesses::value_type InProgressProcess;
 184
 185 } // namespace anon
 186
 187
 188
 189 namespace lyx {
 190 namespace graphics {
 191
 192 class PreviewLoader::Impl : public boost::signals::trackable {
 193 public:
 194         ///
 195         Impl(PreviewLoader & p, Buffer const & b);
 196         /// Stop any InProgress items still executing.
 197         ~Impl();
 198         ///
 199         PreviewImage const * preview(string const & latex_snippet) const;
 200         ///
 201         PreviewLoader::Status status(string const & latex_snippet) const;
 202         ///
 203         void add(string const & latex_snippet);
 204         ///
 205         void remove(string const & latex_snippet);
 206         ///
 207         void startLoading();
 208
 209         /// Emit this signal when an image is ready for display.
 210         boost::signal<void(PreviewImage const &)> imageReady;
 211
 212         Buffer const & buffer() const { return buffer_; }
 213
 214 private:
 215         /// Called by the ForkedCall process that generated the bitmap files.
 216         void finishedGenerating(pid_t, int);
 217         ///
 218         void dumpPreamble(odocstream &) const;
 219         ///
 220         void dumpData(odocstream &, BitmapFile const &) const;
 221
 222         /** cache_ allows easy retrieval of already-generated images
 223          *  using the LaTeX snippet as the identifier.
 224          */
 225         typedef boost::shared_ptr<PreviewImage> PreviewImagePtr;
 226         ///
 227         typedef map<string, PreviewImagePtr> Cache;
 228         ///
 229         Cache cache_;
 230
 231         /** pending_ stores the LaTeX snippets in anticipation of them being
 232          *  sent to the converter.
 233          */
 234         PendingSnippets pending_;
 235
 236         /** in_progress_ stores all forked processes so that we can proceed
 237          *  thereafter.
 238             The map uses the conversion commands as its identifiers.
 239          */
 240         InProgressProcesses in_progress_;
 241
 242         ///
 243         PreviewLoader & parent_;
 244         ///
 245         Buffer const & buffer_;
 246
 247         /// We don't own this
 248         static lyx::Converter const * pconverter_;
 249 };
 250
 251
 252 lyx::Converter const * PreviewLoader::Impl::pconverter_;
 253
 254
 255 //
 256 // The public interface, defined in PreviewLoader.h
 257 //
 258
 259 PreviewLoader::PreviewLoader(Buffer const & b)
 260         : pimpl_(new Impl(*this, b))
 261 {}
 262
 263
 264 PreviewLoader::~PreviewLoader()
 265 {
 266         delete pimpl_;
 267 }
 268
 269
 270 PreviewImage const * PreviewLoader::preview(string const & latex_snippet) const
 271 {
 272         return pimpl_->preview(latex_snippet);
 273 }
 274
 275
 276 PreviewLoader::Status PreviewLoader::status(string const & latex_snippet) const
 277 {
 278         return pimpl_->status(latex_snippet);
 279 }
 280
 281
 282 void PreviewLoader::add(string const & latex_snippet) const
 283 {
 284         pimpl_->add(latex_snippet);
 285 }
 286
 287
 288 void PreviewLoader::remove(string const & latex_snippet) const
 289 {
 290         pimpl_->remove(latex_snippet);
 291 }
 292
 293
 294 void PreviewLoader::startLoading() const
 295 {
 296         pimpl_->startLoading();
 297 }
 298
 299
 300 boost::signals::connection PreviewLoader::connect(slot_type const & slot) const
 301 {
 302         return pimpl_->imageReady.connect(slot);
 303 }
 304
 305
 306 void PreviewLoader::emitSignal(PreviewImage const & pimage) const
 307 {
 308         pimpl_->imageReady(pimage);
 309 }
 310
 311
 312 Buffer const & PreviewLoader::buffer() const
 313 {
 314         return pimpl_->buffer();
 315 }
 316
 317 } // namespace graphics
 318 } // namespace lyx
 319
 320
 321 // The details of the Impl
 322 // =======================
 323
 324 namespace {
 325
 326 class IncrementedFileName {
 327 public:
 328         IncrementedFileName(string const & to_format,
 329                             string const & filename_base)
 330                 : to_format_(to_format), base_(filename_base), counter_(1)
 331         {}
 332
 333         SnippetPair const operator()(string const & snippet)
 334         {
 335                 ostringstream os;
 336                 os << base_ << counter_++ << '.' << to_format_;
 337                 string const file = os.str();
 338
 339                 return make_pair(snippet, FileName(file));
 340         }
 341
 342 private:
 343         string const & to_format_;
 344         string const & base_;
 345         int counter_;
 346 };
 347
 348
 349 InProgress::InProgress(string const & filename_base,
 350                        PendingSnippets const & pending,
 351                        string const & to_format)
 352         : pid(0),
 353           metrics_file(filename_base + ".metrics"),
 354           snippets(pending.size())
 355 {
 356         PendingSnippets::const_iterator pit  = pending.begin();
 357         PendingSnippets::const_iterator pend = pending.end();
 358         BitmapFile::iterator sit = snippets.begin();
 359
 360         transform(pit, pend, sit,
 361                        IncrementedFileName(to_format, filename_base));
 362 }
 363
 364
 365 void InProgress::stop() const
 366 {
 367         if (pid)
 368                 ForkedCallsController::kill(pid, 0);
 369
 370         if (!metrics_file.empty())
 371                 metrics_file.removeFile();
 372
 373         BitmapFile::const_iterator vit  = snippets.begin();
 374         BitmapFile::const_iterator vend = snippets.end();
 375         for (; vit != vend; ++vit) {
 376                 if (!vit->second.empty())
 377                         vit->second.removeFile();
 378         }
 379 }
 380
 381 } // namespace anon
 382
 383
 384 namespace lyx {
 385 namespace graphics {
 386
 387 PreviewLoader::Impl::Impl(PreviewLoader & p, Buffer const & b)
 388         : parent_(p), buffer_(b)
 389 {
 390         if (!pconverter_){
 391                 if (b.params().encoding().package() == Encoding::japanese)
 392                         pconverter_ = setConverter("lyxpreview-platex");
 393                 else
 394                         pconverter_ = setConverter("lyxpreview");
 395         }
 396 }
 397
 398
 399 PreviewLoader::Impl::~Impl()
 400 {
 401         InProgressProcesses::iterator ipit  = in_progress_.begin();
 402         InProgressProcesses::iterator ipend = in_progress_.end();
 403
 404         for (; ipit != ipend; ++ipit)
 405                 ipit->second.stop();
 406 }
 407
 408
 409 PreviewImage const *
 410 PreviewLoader::Impl::preview(string const & latex_snippet) const
 411 {
 412         Cache::const_iterator it = cache_.find(latex_snippet);
 413         return (it == cache_.end()) ? 0 : it->second.get();
 414 }
 415
 416
 417 namespace {
 418
 419 class FindSnippet {
 420 public:
 421         FindSnippet(string const & s) : snippet_(s) {}
 422         bool operator()(InProgressProcess const & process) const
 423         {
 424                 BitmapFile const & snippets = process.second.snippets;
 425                 BitmapFile::const_iterator beg  = snippets.begin();
 426                 BitmapFile::const_iterator end = snippets.end();
 427                 return find_if(beg, end, FindFirst(snippet_)) != end;
 428         }
 429
 430 private:
 431         string const snippet_;
 432 };
 433
 434 } // namespace anon
 435
 436 PreviewLoader::Status
 437 PreviewLoader::Impl::status(string const & latex_snippet) const
 438 {
 439         Cache::const_iterator cit = cache_.find(latex_snippet);
 440         if (cit != cache_.end())
 441                 return Ready;
 442
 443         PendingSnippets::const_iterator pit  = pending_.begin();
 444         PendingSnippets::const_iterator pend = pending_.end();
 445
 446         pit = find(pit, pend, latex_snippet);
 447         if (pit != pend)
 448                 return InQueue;
 449
 450         InProgressProcesses::const_iterator ipit  = in_progress_.begin();
 451         InProgressProcesses::const_iterator ipend = in_progress_.end();
 452
 453         ipit = find_if(ipit, ipend, FindSnippet(latex_snippet));
 454         if (ipit != ipend)
 455                 return Processing;
 456
 457         return NotFound;
 458 }
 459
 460
 461 void PreviewLoader::Impl::add(string const & latex_snippet)
 462 {
 463         if (!pconverter_ || status(latex_snippet) != NotFound)
 464                 return;
 465
 466         string const snippet = trim(latex_snippet);
 467         if (snippet.empty())
 468                 return;
 469
 470         LYXERR(Debug::GRAPHICS, "adding snippet:\n" << snippet);
 471
 472         pending_.push_back(snippet);
 473 }
 474
 475
 476 namespace {
 477
 478 class EraseSnippet {
 479 public:
 480         EraseSnippet(string const & s) : snippet_(s) {}
 481         void operator()(InProgressProcess & process)
 482         {
 483                 BitmapFile & snippets = process.second.snippets;
 484                 BitmapFile::iterator it  = snippets.begin();
 485                 BitmapFile::iterator end = snippets.end();
 486
 487                 it = find_if(it, end, FindFirst(snippet_));
 488                 if (it != end)
 489                         snippets.erase(it, it+1);
 490         }
 491
 492 private:
 493         string const & snippet_;
 494 };
 495
 496 } // namespace anon
 497
 498
 499 void PreviewLoader::Impl::remove(string const & latex_snippet)
 500 {
 501         Cache::iterator cit = cache_.find(latex_snippet);
 502         if (cit != cache_.end())
 503                 cache_.erase(cit);
 504
 505         PendingSnippets::iterator pit  = pending_.begin();
 506         PendingSnippets::iterator pend = pending_.end();
 507
 508         pending_.erase(std::remove(pit, pend, latex_snippet), pend);
 509
 510         InProgressProcesses::iterator ipit  = in_progress_.begin();
 511         InProgressProcesses::iterator ipend = in_progress_.end();
 512
 513         for_each(ipit, ipend, EraseSnippet(latex_snippet));
 514
 515         while (ipit != ipend) {
 516                 InProgressProcesses::iterator curr = ipit++;
 517                 if (curr->second.snippets.empty())
 518                         in_progress_.erase(curr);
 519         }
 520 }
 521
 522
 523 void PreviewLoader::Impl::startLoading()
 524 {
 525         if (pending_.empty() || !pconverter_)
 526                 return;
 527
 528         // Only start the process off after the buffer is loaded from file.
 529         if (!buffer_.isFullyLoaded())
 530                 return;
 531
 532         LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()");
 533
 534         // As used by the LaTeX file and by the resulting image files
 535         string const directory = buffer_.temppath();
 536
 537         string const filename_base = unique_filename(directory);
 538
 539         // Create an InProgress instance to place in the map of all
 540         // such processes if it starts correctly.
 541         InProgress inprogress(filename_base, pending_, pconverter_->to);
 542
 543         // clear pending_, so we're ready to start afresh.
 544         pending_.clear();
 545
 546         // Output the LaTeX file.
 547         FileName const latexfile(filename_base + ".tex");
 548
 549         // we use the encoding of the buffer
 550         Encoding const & enc = buffer_.params().encoding();
 551         ofdocstream of;
 552         try { of.reset(enc.iconvName()); }
 553         catch (iconv_codecvt_facet_exception & e) {
 554                 LYXERR0("Caught iconv exception: " << e.what()
 555                         << "\nUnable to create LaTeX file: " << latexfile);
 556                 return;
 557         }
 558
 559         TexRow texrow;
 560         OutputParams runparams(&enc);
 561         LaTeXFeatures features(buffer_, buffer_.params(), runparams);
 562
 563         if (!openFileWrite(of, latexfile))
 564                 return;
 565
 566         if (!of) {
 567                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 568                                         << "Unable to create LaTeX file\n" << latexfile);
 569                 return;
 570         }
 571         of << "\\batchmode\n";
 572         dumpPreamble(of);
 573         // handle inputenc etc.
 574         buffer_.params().writeEncodingPreamble(of, features, texrow);
 575         of << "\n\\begin{document}\n";
 576         dumpData(of, inprogress.snippets);
 577         of << "\n\\end{document}\n";
 578         of.close();
 579         if (of.fail()) {
 580                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 581                                          << "File was not closed properly.");
 582                 return;
 583         }
 584
 585         double font_scaling_factor = 0.01 * lyxrc.dpi * lyxrc.zoom
 586                 * lyxrc.preview_scale_factor;
 587
 588         // The conversion command.
 589         ostringstream cs;
 590         cs << pconverter_->command << ' ' << pconverter_->to << ' '
 591            << quoteName(latexfile.toFilesystemEncoding()) << ' '
 592            << int(font_scaling_factor) << ' '
 593            << theApp()->hexName(PreviewLoader::foregroundColor()) << ' '
 594            << theApp()->hexName(PreviewLoader::backgroundColor());
 595
 596         string const command = libScriptSearch(cs.str());
 597
 598         // Initiate the conversion from LaTeX to bitmap images files.
 599         ForkedCall::SignalTypePtr
 600                 convert_ptr(new ForkedCall::SignalType);
 601         convert_ptr->connect(bind(&Impl::finishedGenerating, this, _1, _2));
 602
 603         ForkedCall call;
 604         int ret = call.startScript(command, convert_ptr);
 605
 606         if (ret != 0) {
 607                 LYXERR(Debug::GRAPHICS, "PreviewLoader::startLoading()\n"
 608                                         << "Unable to start process\n" << command);
 609                 return;
 610         }
 611
 612         // Store the generation process in a list of all such processes
 613         inprogress.pid = call.pid();
 614         inprogress.command = command;
 615         in_progress_[inprogress.pid] = inprogress;
 616 }
 617
 618
 619 void PreviewLoader::Impl::finishedGenerating(pid_t pid, int retval)
 620 {
 621         // Paranoia check!
 622         InProgressProcesses::iterator git = in_progress_.find(pid);
 623         if (git == in_progress_.end()) {
 624                 lyxerr << "PreviewLoader::finishedGenerating(): unable to find "
 625                         "data for PID " << pid << endl;
 626                 return;
 627         }
 628
 629         string const command = git->second.command;
 630         string const status = retval > 0 ? "failed" : "succeeded";
 631         LYXERR(Debug::GRAPHICS, "PreviewLoader::finishedInProgress("
 632                                 << retval << "): processing " << status
 633                                 << " for " << command);
 634         if (retval > 0)
 635                 return;
 636
 637         // Read the metrics file, if it exists
 638         vector<double> ascent_fractions(git->second.snippets.size());
 639         setAscentFractions(ascent_fractions, git->second.metrics_file);
 640
 641         // Add these newly generated bitmap files to the cache and
 642         // start loading them into LyX.
 643         BitmapFile::const_iterator it  = git->second.snippets.begin();
 644         BitmapFile::const_iterator end = git->second.snippets.end();
 645
 646         list<PreviewImagePtr> newimages;
 647
 648         int metrics_counter = 0;
 649         for (; it != end; ++it, ++metrics_counter) {
 650                 string const & snip = it->first;
 651                 FileName const & file = it->second;
 652                 double af = ascent_fractions[metrics_counter];
 653
 654                 PreviewImagePtr ptr(new PreviewImage(parent_, snip, file, af));
 655                 cache_[snip] = ptr;
 656
 657                 newimages.push_back(ptr);
 658         }
 659
 660         // Remove the item from the list of still-executing processes.
 661         in_progress_.erase(git);
 662
 663         // Tell the outside world
 664         list<PreviewImagePtr>::const_reverse_iterator
 665                 nit  = newimages.rbegin();
 666         list<PreviewImagePtr>::const_reverse_iterator
 667                 nend = newimages.rend();
 668         for (; nit != nend; ++nit) {
 669                 imageReady(*nit->get());
 670         }
 671 }
 672
 673
 674 void PreviewLoader::Impl::dumpPreamble(odocstream & os) const
 675 {
 676         // Dump the preamble only.
 677         // We don't need an encoding for runparams since it is not used by
 678         // the preamble.
 679         OutputParams runparams(0);
 680         runparams.flavor = OutputParams::LATEX;
 681         runparams.nice = true;
 682         runparams.moving_arg = true;
 683         runparams.free_spacing = true;
 684         buffer_.writeLaTeXSource(os, buffer_.filePath(), runparams, true, false);
 685
 686         // FIXME! This is a HACK! The proper fix is to control the 'true'
 687         // passed to WriteStream below:
 688         // int InsetMathNest::latex(Buffer const &, odocstream & os,
 689         //                          OutputParams const & runparams) const
 690         // {
 691         //      WriteStream wi(os, runparams.moving_arg, true);
 692         //      par_->write(wi);
 693         //      return wi.line();
 694         // }
 695         os << "\n"
 696            << "\\def\\lyxlock{}\n"
 697            << "\n";
 698
 699         // All equation labels appear as "(#)" + preview.sty's rendering of
 700         // the label name
 701         if (lyxrc.preview_hashed_labels)
 702                 os << "\\renewcommand{\\theequation}{\\#}\n";
 703
 704         // Use the preview style file to ensure that each snippet appears on a
 705         // fresh page.
 706         // Also support PDF output (automatically generated e.g. when
 707         // \usepackage[pdftex]{hyperref} is used.
 708         os << "\n"
 709            << "\\newif\\ifpdf\n"
 710            << "\\ifx\\pdfoutput\\undefined\n"
 711            << "\\else\\ifx\\pdfoutput\\relax\n"
 712            << "\\else\\ifnum0=\\pdfoutput\n"
 713            << "\\else\\pdftrue\\fi\\fi\\fi\n"
 714            << "\\ifpdf\n"
 715            << "  \\usepackage[active,delayed,tightpage,showlabels,lyx,pdftex]{preview}\n"
 716            << "\\else\n"
 717            << "  \\usepackage[active,delayed,showlabels,lyx,dvips]{preview}\n"
 718            << "\\fi\n"
 719            << "\n";
 720 }
 721
 722
 723 void PreviewLoader::Impl::dumpData(odocstream & os,
 724                                    BitmapFile const & vec) const
 725 {
 726         if (vec.empty())
 727                 return;
 728
 729         BitmapFile::const_iterator it  = vec.begin();
 730         BitmapFile::const_iterator end = vec.end();
 731
 732         for (; it != end; ++it) {
 733                 // FIXME UNICODE
 734                 os << "\\begin{preview}\n"
 735                    << from_utf8(it->first)
 736                    << "\n\\end{preview}\n\n";
 737         }
 738 }
 739
 740 } // namespace graphics
 741 } // namespace lyx