src/graphics/GraphicsConverter.C

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