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 "support/bind.h"
  28 #include "support/TempFile.h"
  29
  30 #include <sstream>
  31 #include <fstream>
  32
  33 using namespace std;
  34 using namespace lyx::support;
  35
  36 namespace lyx {
  37
  38 namespace graphics {
  39
  40 class Converter::Impl : public boost::signals2::trackable {
  41 public:
  42         ///
  43         Impl(FileName const &, string const &, string const &, string const &);
  44
  45         ///
  46         void startConversion();
  47
  48         /** This method is connected to a signal passed to the forked call
  49          *  class, passing control back here when the conversion is completed.
  50          *  Cleans-up the temporary files, emits the finishedConversion
  51          *  signal and removes the Converter from the list of all processes.
  52          */
  53         void converted(pid_t pid, int retval);
  54
  55         /** At the end of the conversion process inform the outside world
  56          *  by emitting a signal.
  57          */
  58         typedef boost::signals2::signal<void(bool)> SignalType;
  59         ///
  60         SignalType finishedConversion;
  61
  62         ///
  63         string script_command_;
  64         ///
  65         FileName script_file_;
  66         ///
  67         FileName to_file_;
  68         ///
  69         bool valid_process_;
  70         ///
  71         bool finished_;
  72 };
  73
  74
  75 bool Converter::isReachable(string const & from_format_name,
  76                             string const & to_format_name)
  77 {
  78         return theConverters().isReachable(from_format_name, to_format_name);
  79 }
  80
  81
  82 Converter::Converter(FileName const & from_file, string const & to_file_base,
  83                      string const & from_format, string const & to_format)
  84         : pimpl_(new Impl(from_file, to_file_base, from_format, to_format))
  85 {}
  86
  87
  88 Converter::~Converter()
  89 {
  90         delete pimpl_;
  91 }
  92
  93
  94 void Converter::startConversion() const
  95 {
  96         pimpl_->startConversion();
  97 }
  98
  99
 100 boost::signals2::connection Converter::connect(slot_type const & slot) const
 101 {
 102         return pimpl_->finishedConversion.connect(slot);
 103 }
 104
 105
 106 FileName const & Converter::convertedFile() const
 107 {
 108         static FileName const empty;
 109         return pimpl_->finished_ ? pimpl_->to_file_ : empty;
 110 }
 111
 112 /** Build the conversion script.
 113  *  The script is output to the stream \p script.
 114  */
 115 static void build_script(string const & from_file, string const & to_file_base,
 116                   string const & from_format, string const & to_format,
 117                   ostream & script);
 118
 119
 120 Converter::Impl::Impl(FileName const & from_file, string const & to_file_base,
 121                       string const & from_format, string const & to_format)
 122         : valid_process_(false), finished_(false)
 123 {
 124         LYXERR(Debug::GRAPHICS, "Converter c-tor:\n"
 125                 << "\tfrom_file:      " << from_file
 126                 << "\n\tto_file_base: " << to_file_base
 127                 << "\n\tfrom_format:  " << from_format
 128                 << "\n\tto_format:    " << to_format);
 129
 130         // The converted image is to be stored in this file (we do not
 131         // use ChangeExtension because this is a basename which may
 132         // nevertheless contain a '.')
 133         to_file_ = FileName(to_file_base + '.' +  formats.extension(to_format));
 134
 135         // The conversion commands are stored in a stringstream
 136         ostringstream script;
 137         build_script(from_file.toFilesystemEncoding(),
 138                      to_file_.toFilesystemEncoding(),
 139                      from_format, to_format, script);
 140         LYXERR(Debug::GRAPHICS, "\tConversion script:"
 141                    "\n--------------------------------------\n"
 142                 << script.str()
 143                 << "\n--------------------------------------\n");
 144
 145         // Output the script to file.
 146         TempFile tempfile(to_file_.onlyPath(), "lyxconvertXXXXXX.py");
 147         tempfile.setAutoRemove(false);
 148         script_file_ = tempfile.name();
 149
 150         ofstream fs(script_file_.toFilesystemEncoding().c_str());
 151         if (!fs.good()) {
 152                 lyxerr << "Unable to write the conversion script to \""
 153                        << script_file_ << '\n'
 154                        << "Please check your directory permissions."
 155                        << endl;
 156                 return;
 157         }
 158
 159         fs << script.str();
 160         fs.close();
 161
 162         // The command needed to run the conversion process
 163         // We create a dummy command for ease of understanding of the
 164         // list of forked processes.
 165         // Note: 'python ' is absolutely essential, or execvp will fail.
 166         script_command_ = os::python() + ' ' +
 167                 quoteName(script_file_.toFilesystemEncoding()) + ' ' +
 168                 quoteName(onlyFileName(from_file.toFilesystemEncoding())) + ' ' +
 169                 quoteName(to_format);
 170         // All is ready to go
 171         valid_process_ = true;
 172 }
 173
 174
 175 void Converter::Impl::startConversion()
 176 {
 177         if (!valid_process_) {
 178                 converted(0, 1);
 179                 return;
 180         }
 181
 182         ForkedCall::SignalTypePtr ptr =
 183                 ForkedCallQueue::add(script_command_);
 184         ptr->connect(bind(&Impl::converted, this, _1, _2));
 185 }
 186
 187
 188 void Converter::Impl::converted(pid_t /* pid */, int retval)
 189 {
 190         if (finished_)
 191                 // We're done already!
 192                 return;
 193
 194         finished_ = true;
 195         // Clean-up behind ourselves
 196         script_file_.removeFile();
 197
 198         if (retval > 0) {
 199                 to_file_.removeFile();
 200                 to_file_.erase();
 201                 finishedConversion(false);
 202         } else {
 203                 finishedConversion(true);
 204         }
 205 }
 206
 207
 208 static string const move_file(string const & from_file, string const & to_file)
 209 {
 210         if (from_file == to_file)
 211                 return string();
 212
 213         ostringstream command;
 214         command << "fromfile = " << from_file << "\n"
 215                 << "tofile = "   << to_file << "\n\n"
 216                 << "try:\n"
 217                 << "  os.rename(fromfile, tofile)\n"
 218                 << "except:\n"
 219                 << "  try:\n"
 220                 << "    shutil.copy(fromfile, tofile)\n"
 221                 << "  except:\n"
 222                 << "    sys.exit(1)\n"
 223                 << "  unlinkNoThrow(fromfile)\n";
 224
 225         return command.str();
 226 }
 227
 228
 229 static void build_conversion_command(string const & command, ostream & script)
 230 {
 231         // Store in the python script
 232         script << "\nif os.system(r'" << command << "') != 0:\n";
 233
 234         // Test that this was successful. If not, remove
 235         // ${outfile} and exit the python script
 236         script << "  unlinkNoThrow(outfile)\n"
 237                << "  sys.exit(1)\n\n";
 238
 239         // Test that the outfile exists.
 240         // ImageMagick's convert will often create ${outfile}.0,
 241         // ${outfile}.1.
 242         // If this occurs, move ${outfile}.0 to ${outfile}
 243         // and delete ${outfile}.? (ignore errors)
 244         script << "if not os.path.isfile(outfile):\n"
 245                   "  if os.path.isfile(outfile + '.0'):\n"
 246                   "    os.rename(outfile + '.0', outfile)\n"
 247                   "    import glob\n"
 248                   "    for file in glob.glob(outfile + '.?'):\n"
 249                   "      unlinkNoThrow(file)\n"
 250                   "  else:\n"
 251                   "    sys.exit(1)\n\n";
 252
 253         // Delete the infile
 254         script << "if infile != outfile:\n"
 255                   "  unlinkNoThrow(infile)\n\n";
 256 }
 257
 258
 259 static string const strip_digit(string const & format)
 260 {
 261         // Strip trailing digits from format names e.g. "pdf6" -> "pdf"
 262         return format.substr(0, format.find_last_not_of("0123456789") + 1);
 263 }
 264
 265
 266 static void build_script(string const & from_file,
 267                   string const & to_file,
 268                   string const & from_format,
 269                   string const & to_format,
 270                   ostream & script)
 271 {
 272         LASSERT(from_format != to_format, return);
 273         LYXERR(Debug::GRAPHICS, "build_script ... ");
 274         typedef Graph::EdgePath EdgePath;
 275
 276         script << "#!/usr/bin/env python\n"
 277                   "# -*- coding: utf-8 -*-\n"
 278                   "import os, shutil, sys\n\n"
 279                   "def unlinkNoThrow(file):\n"
 280                   "  ''' remove a file, do not throw if an error occurs '''\n"
 281                   "  try:\n"
 282                   "    os.unlink(file)\n"
 283                   "  except:\n"
 284                   "    pass\n\n";
 285
 286         EdgePath const edgepath = from_format.empty() ?
 287                 EdgePath() :
 288                 theConverters().getPath(from_format, to_format);
 289
 290         // Create a temporary base file-name for all intermediate steps.
 291         string const from_ext = getExtension(from_file);
 292         TempFile tempfile(addExtension("gconvertXXXXXX", from_ext));
 293         tempfile.setAutoRemove(false);
 294         string outfile = tempfile.name().toFilesystemEncoding();
 295         string const to_base = from_ext.empty() ? outfile : removeExtension(outfile);
 296
 297         // Create a copy of the file in case the original name contains
 298         // problematic characters like ' or ". We can work around that problem
 299         // in python, but the converters might be shell scripts and have more
 300         // troubles with it.
 301         script << "infile = "
 302                         << quoteName(from_file, quote_python)
 303                         << "\n"
 304                   "outfile = "
 305                         << quoteName(outfile, quote_python) << "\n"
 306                   "shutil.copy(infile, outfile)\n";
 307
 308         // Some converters (e.g. lilypond) can only output files to the
 309         // current directory, so we need to change the current directory.
 310         // This has the added benefit that all other files that may be
 311         // generated by the converter are deleted when LyX closes and do not
 312         // clutter the real working directory.
 313         script << "os.chdir("
 314                << quoteName(onlyPath(outfile)) << ")\n";
 315
 316         if (edgepath.empty()) {
 317                 // Either from_format is unknown or we don't have a
 318                 // converter path from from_format to to_format, so we use
 319                 // the default converter.
 320                 script << "infile = outfile\n"
 321                        << "outfile = "
 322                        << quoteName(to_file, quote_python) << "\n";
 323
 324                 ostringstream os;
 325                 os << os::python() << ' '
 326                    << commandPrep("$$s/scripts/convertDefault.py") << ' ';
 327                 if (from_format.empty())
 328                         os << "unknown ";
 329                 else
 330                         os << strip_digit(from_format) << ' ';
 331                 // The extra " quotes around infile and outfile are needed
 332                 // because the filename may contain spaces and it is used
 333                 // as argument of os.system().
 334                 os << "' + '\"' + infile + '\"' + ' "
 335                    << strip_digit(to_format) << " ' + '\"' + outfile + '\"' + '";
 336                 string const command = os.str();
 337
 338                 LYXERR(Debug::GRAPHICS,
 339                         "\tNo converter defined! I use convertDefault.py\n\t"
 340                         << command);
 341
 342                 build_conversion_command(command, script);
 343         }
 344
 345         // The conversion commands may contain these tokens that need to be
 346         // changed to infile, infile_base, outfile and output directory respectively.
 347         string const token_from  = "$$i";
 348         string const token_base  = "$$b";
 349         string const token_to    = "$$o";
 350         string const token_todir = "$$d";
 351
 352         EdgePath::const_iterator it  = edgepath.begin();
 353         EdgePath::const_iterator end = edgepath.end();
 354
 355         for (; it != end; ++it) {
 356                 lyx::Converter const & conv = theConverters().get(*it);
 357
 358                 // Build the conversion command
 359                 string const infile      = outfile;
 360                 string const infile_base = changeExtension(infile, string());
 361                 outfile = conv.result_file().empty()
 362                         ? addExtension(to_base, conv.To()->extension())
 363                         : addName(subst(conv.result_dir(),
 364                                         token_base, infile_base),
 365                                   subst(conv.result_file(),
 366                                         token_base, onlyFileName(infile_base)));
 367
 368                 // If two formats share the same extension we may get identical names
 369                 if (outfile == infile && conv.result_file().empty()) {
 370                         TempFile tempfile(addExtension("gconvertXXXXXX", conv.To()->extension()));
 371                         tempfile.setAutoRemove(false);
 372                         outfile = tempfile.name().toFilesystemEncoding();
 373                 }
 374
 375                 // Store these names in the python script
 376                 script << "infile = "
 377                                 << quoteName(infile, quote_python) << "\n"
 378                           "infile_base = "
 379                                 << quoteName(infile_base, quote_python) << "\n"
 380                           "outfile = "
 381                                 << quoteName(outfile, quote_python) << "\n"
 382                           "outdir  = os.path.dirname(outfile)\n" ;
 383
 384                 // See comment about extra " quotes above (although that
 385                 // applies only for the first loop run here).
 386                 string command = conv.command();
 387                 command = subst(command, token_from,  "' + '\"' + infile + '\"' + '");
 388                 command = subst(command, token_base,  "' + '\"' + infile_base + '\"' + '");
 389                 command = subst(command, token_to,    "' + '\"' + outfile + '\"' + '");
 390                 command = subst(command, token_todir, "' + '\"' + outdir + '\"' + '");
 391
 392                 build_conversion_command(command, script);
 393         }
 394
 395         // Move the final outfile to to_file
 396         script << move_file("outfile", quoteName(to_file, quote_python));
 397         LYXERR(Debug::GRAPHICS, "ready!");
 398 }
 399
 400 } // namespace graphics
 401 } // namespace lyx