src/graphics/GraphicsConverter.cpp

   1 /**
   2  * \file GraphicsConverter.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 "GraphicsConverter.h"
  14
  15 #include "Converter.h"
  16 #include "Format.h"
  17
  18 #include "support/lassert.h"
  19 #include "support/convert.h"
  20 #include "support/debug.h"
  21 #include "support/FileName.h"
  22 #include "support/filetools.h"
  23 #include "support/ForkedCalls.h"
  24 #include "support/lstrings.h"
  25 #include "support/os.h"
  26
  27 #include <boost/bind.hpp>
  28
  29 #include <sstream>
  30 #include <fstream>
  31
  32 using namespace std;
  33 using namespace lyx::support;
  34
  35 namespace lyx {
  36
  37 namespace graphics {
  38
  39 class Converter::Impl : public boost::signals::trackable {
  40 public:
  41         ///
  42         Impl(FileName const &, string const &, string const &, string const &);
  43
  44         ///
  45         void startConversion();
  46
  47         /** This method is connected to a signal passed to the forked call
  48          *  class, passing control back here when the conversion is completed.
  49          *  Cleans-up the temporary files, emits the finishedConversion
  50          *  signal and removes the Converter from the list of all processes.
  51          */
  52         void converted(pid_t pid, int retval);
  53
  54         /** At the end of the conversion process inform the outside world
  55          *  by emitting a signal.
  56          */
  57         typedef boost::signal<void(bool)> SignalType;
  58         ///
  59         SignalType finishedConversion;
  60
  61         ///
  62         string script_command_;
  63         ///
  64         FileName script_file_;
  65         ///
  66         FileName to_file_;
  67         ///
  68         bool valid_process_;
  69         ///
  70         bool finished_;
  71 };
  72
  73
  74 bool Converter::isReachable(string const & from_format_name,
  75                             string const & to_format_name)
  76 {
  77         return theConverters().isReachable(from_format_name, to_format_name);
  78 }
  79
  80
  81 Converter::Converter(FileName const & from_file, string const & to_file_base,
  82                      string const & from_format, string const & to_format)
  83         : pimpl_(new Impl(from_file, to_file_base, from_format, to_format))
  84 {}
  85
  86
  87 Converter::~Converter()
  88 {
  89         delete pimpl_;
  90 }
  91
  92
  93 void Converter::startConversion() const
  94 {
  95         pimpl_->startConversion();
  96 }
  97
  98
  99 boost::signals::connection Converter::connect(slot_type const & slot) const
 100 {
 101         return pimpl_->finishedConversion.connect(slot);
 102 }
 103
 104
 105 FileName const & Converter::convertedFile() const
 106 {
 107         static FileName const empty;
 108         return pimpl_->finished_ ? pimpl_->to_file_ : empty;
 109 }
 110
 111 /** Build the conversion script.
 112  *  The script is output to the stream \p script.
 113  */
 114 static void build_script(FileName const & from_file, string const & to_file_base,
 115                   string const & from_format, string const & to_format,
 116                   ostream & script);
 117
 118
 119 Converter::Impl::Impl(FileName const & from_file, string const & to_file_base,
 120                       string const & from_format, string const & to_format)
 121         : valid_process_(false), finished_(false)
 122 {
 123         LYXERR(Debug::GRAPHICS, "Converter c-tor:\n"
 124                 << "\tfrom_file:      " << from_file
 125                 << "\n\tto_file_base: " << to_file_base
 126                 << "\n\tfrom_format:  " << from_format
 127                 << "\n\tto_format:    " << to_format);
 128
 129         // The converted image is to be stored in this file (we do not
 130         // use ChangeExtension because this is a basename which may
 131         // nevertheless contain a '.')
 132         to_file_ = FileName(to_file_base + '.' +  formats.extension(to_format));
 133
 134         // The conversion commands are stored in a stringstream
 135         ostringstream script;
 136         build_script(from_file, to_file_base, from_format, to_format, script);
 137         LYXERR(Debug::GRAPHICS, "\tConversion script:"
 138                    "\n--------------------------------------\n"
 139                 << script.str()
 140                 << "\n--------------------------------------\n");
 141
 142         // Output the script to file.
 143         static int counter = 0;
 144         script_file_ = FileName(onlyPath(to_file_base) + "lyxconvert" +
 145                 convert<string>(counter++) + ".py");
 146
 147         ofstream fs(script_file_.toFilesystemEncoding().c_str());
 148         if (!fs.good()) {
 149                 lyxerr << "Unable to write the conversion script to \""
 150                        << script_file_ << '\n'
 151                        << "Please check your directory permissions."
 152                        << endl;
 153                 return;
 154         }
 155
 156         fs << script.str();
 157         fs.close();
 158
 159         // The command needed to run the conversion process
 160         // We create a dummy command for ease of understanding of the
 161         // list of forked processes.
 162         // Note: 'python ' is absolutely essential, or execvp will fail.
 163         script_command_ = os::python() + ' ' +
 164                 quoteName(script_file_.toFilesystemEncoding()) + ' ' +
 165                 quoteName(onlyFilename(from_file.toFilesystemEncoding())) + ' ' +
 166                 quoteName(to_format);
 167         // All is ready to go
 168         valid_process_ = true;
 169 }
 170
 171
 172 void Converter::Impl::startConversion()
 173 {
 174         if (!valid_process_) {
 175                 converted(0, 1);
 176                 return;
 177         }
 178
 179         ForkedCall::SignalTypePtr ptr =
 180                 ForkedCallQueue::add(script_command_);
 181         ptr->connect(boost::bind(&Impl::converted, this, _1, _2));
 182 }
 183
 184
 185 void Converter::Impl::converted(pid_t /* pid */, int retval)
 186 {
 187         if (finished_)
 188                 // We're done already!
 189                 return;
 190
 191         finished_ = true;
 192         // Clean-up behind ourselves
 193         script_file_.removeFile();
 194
 195         if (retval > 0) {
 196                 to_file_.removeFile();
 197                 to_file_.erase();
 198                 finishedConversion(false);
 199         } else {
 200                 finishedConversion(true);
 201         }
 202 }
 203
 204
 205 static string const move_file(string const & from_file, string const & to_file)
 206 {
 207         if (from_file == to_file)
 208                 return string();
 209
 210         ostringstream command;
 211         command << "fromfile = utf8ToDefaultEncoding(" << from_file << ")\n"
 212                 << "tofile = utf8ToDefaultEncoding("   << to_file << ")\n\n"
 213                 << "try:\n"
 214                 << "  os.rename(fromfile, tofile)\n"
 215                 << "except:\n"
 216                 << "  try:\n"
 217                 << "    shutil.copy(fromfile, tofile)\n"
 218                 << "  except:\n"
 219                 << "    sys.exit(1)\n"
 220                 << "  unlinkNoThrow(fromfile)\n";
 221
 222         return command.str();
 223 }
 224
 225
 226 static void build_conversion_command(string const & command, ostream & script)
 227 {
 228         // Store in the python script
 229         script << "\nif os.system(r'" << command << "') != 0:\n";
 230
 231         // Test that this was successful. If not, remove
 232         // ${outfile} and exit the python script
 233         script << "  unlinkNoThrow(outfile)\n"
 234                << "  sys.exit(1)\n\n";
 235
 236         // Test that the outfile exists.
 237         // ImageMagick's convert will often create ${outfile}.0,
 238         // ${outfile}.1.
 239         // If this occurs, move ${outfile}.0 to ${outfile}
 240         // and delete ${outfile}.? (ignore errors)
 241         script << "if not os.path.isfile(outfile):\n"
 242                   "  if os.path.isfile(outfile + '.0'):\n"
 243                   "    os.rename(outfile + '.0', outfile)\n"
 244                   "    import glob\n"
 245                   "    for file in glob.glob(outfile + '.?'):\n"
 246                   "      unlinkNoThrow(file)\n"
 247                   "  else:\n"
 248                   "    sys.exit(1)\n\n";
 249
 250         // Delete the infile
 251         script << "unlinkNoThrow(infile)\n\n";
 252 }
 253
 254
 255 static void build_script(FileName const & from_file,
 256                   string const & to_file_base,
 257                   string const & from_format,
 258                   string const & to_format,
 259                   ostream & script)
 260 {
 261         LASSERT(from_format != to_format, /**/);
 262         LYXERR(Debug::GRAPHICS, "build_script ... ");
 263         typedef Graph::EdgePath EdgePath;
 264
 265         script << "#!/usr/bin/env python\n"
 266                   "# -*- coding: utf-8 -*-\n"
 267                   "import os, shutil, sys, locale\n\n"
 268                   "def unlinkNoThrow(file):\n"
 269                   "  ''' remove a file, do not throw if an error occurs '''\n"
 270                   "  try:\n"
 271                   "    os.unlink(file)\n"
 272                   "  except:\n"
 273                   "    pass\n\n"
 274                   "def utf8ToDefaultEncoding(file):\n"
 275                   "  ''' if possible, convert to the default encoding '''\n"
 276                   "  try:\n"
 277                   "    language, output_encoding = locale.getdefaultlocale()\n"
 278                   "    if output_encoding == None:\n"
 279                   "      output_encoding = 'latin1'\n"
 280                   "    return unicode(file, 'utf8').encode(output_encoding)\n"
 281                   "  except:\n"
 282                   "    return file\n\n";
 283
 284         // we do not use ChangeExtension because this is a basename
 285         // which may nevertheless contain a '.'
 286         string const to_file = to_file_base + '.'
 287                 + formats.extension(to_format);
 288
 289         EdgePath const edgepath = from_format.empty() ?
 290                 EdgePath() :
 291                 theConverters().getPath(from_format, to_format);
 292
 293         // Create a temporary base file-name for all intermediate steps.
 294         // Remember to remove the temp file because we only want the name...
 295         static int counter = 0;
 296         string const tmp = "gconvert" + convert<string>(counter++);
 297         FileName const to_base = FileName::tempName(tmp);
 298
 299         // Create a copy of the file in case the original name contains
 300         // problematic characters like ' or ". We can work around that problem
 301         // in python, but the converters might be shell scripts and have more
 302         // troubles with it.
 303         string outfile = addExtension(to_base.absFilename(), getExtension(from_file.absFilename()));
 304         script << "infile = utf8ToDefaultEncoding("
 305                         << quoteName(from_file.absFilename(), quote_python)
 306                         << ")\n"
 307                   "outfile = utf8ToDefaultEncoding("
 308                         << quoteName(outfile, quote_python) << ")\n"
 309                   "shutil.copy(infile, outfile)\n";
 310
 311         // Some converters (e.g. lilypond) can only output files to the
 312         // current directory, so we need to change the current directory.
 313         // This has the added benefit that all other files that may be
 314         // generated by the converter are deleted when LyX closes and do not
 315         // clutter the real working directory.
 316         script << "os.chdir(utf8ToDefaultEncoding("
 317                << quoteName(onlyPath(outfile)) << "))\n";
 318
 319         if (edgepath.empty()) {
 320                 // Either from_format is unknown or we don't have a
 321                 // converter path from from_format to to_format, so we use
 322                 // the default converter.
 323                 script << "infile = outfile\n"
 324                        << "outfile = utf8ToDefaultEncoding("
 325                        << quoteName(to_file, quote_python) << ")\n";
 326
 327                 ostringstream os;
 328                 os << os::python() << ' '
 329                    << libScriptSearch("$$s/scripts/convertDefault.py",
 330                                       quote_python) << ' ';
 331                 if (!from_format.empty())
 332                         os << from_format << ':';
 333                 // The extra " quotes around infile and outfile are needed
 334                 // because the filename may contain spaces and it is used
 335                 // as argument of os.system().
 336                 os << "' + '\"' + infile + '\"' + ' "
 337                    << to_format << ":' + '\"' + outfile + '\"' + '";
 338                 string const command = os.str();
 339
 340                 LYXERR(Debug::GRAPHICS,
 341                         "\tNo converter defined! I use convertDefault.py\n\t"
 342                         << command);
 343
 344                 build_conversion_command(command, script);
 345         }
 346
 347         // The conversion commands may contain these tokens that need to be
 348         // changed to infile, infile_base, outfile and output directory respectively.
 349         string const token_from  = "$$i";
 350         string const token_base  = "$$b";
 351         string const token_to    = "$$o";
 352         string const token_todir = "$$d";
 353
 354         EdgePath::const_iterator it  = edgepath.begin();
 355         EdgePath::const_iterator end = edgepath.end();
 356
 357         for (; it != end; ++it) {
 358                 lyx::Converter const & conv = theConverters().get(*it);
 359
 360                 // Build the conversion command
 361                 string const infile      = outfile;
 362                 string const infile_base = changeExtension(infile, string());
 363                 outfile = addExtension(to_base.absFilename(), conv.To->extension());
 364
 365                 // Store these names in the python script
 366                 script << "infile = utf8ToDefaultEncoding("
 367                                 << quoteName(infile, quote_python) << ")\n"
 368                           "infile_base = utf8ToDefaultEncoding("
 369                                 << quoteName(infile_base, quote_python) << ")\n"
 370                           "outfile = utf8ToDefaultEncoding("
 371                                 << quoteName(outfile, quote_python) << ")\n"
 372                           "outdir  = os.path.dirname(outfile)\n" ;
 373
 374                 // See comment about extra " quotes above (although that
 375                 // applies only for the first loop run here).
 376                 string command = conv.command;
 377                 command = subst(command, token_from,  "' + '\"' + infile + '\"' + '");
 378                 command = subst(command, token_base,  "' + '\"' + infile_base + '\"' + '");
 379                 command = subst(command, token_to,    "' + '\"' + outfile + '\"' + '");
 380                 command = subst(command, token_todir, "' + '\"' + outdir + '\"' + '");
 381                 command = libScriptSearch(command, quote_python);
 382
 383                 build_conversion_command(command, script);
 384         }
 385
 386         // Move the final outfile to to_file
 387         script << move_file("outfile", quoteName(to_file, quote_python));
 388         LYXERR(Debug::GRAPHICS, "ready!");
 389 }
 390
 391 } // namespace graphics
 392 } // namespace lyx