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+/* Zupdate - recompress bzip2, gzip, xz files to lzip files
+ Copyright (C) 2013 Antonio Diaz Diaz.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define _FILE_OFFSET_BITS 64
+
+#include <cerrno>
+#include <climits>
+#include <csignal>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <list>
+#include <string>
+#include <vector>
+#include <dirent.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <utime.h>
+#include <sys/stat.h>
+#if defined(__MSVCRT__) || defined(__OS2__)
+#include <io.h>
+#endif
+
+#include "arg_parser.h"
+#include "zutils.h"
+#include "rc.h"
+
+#if CHAR_BIT != 8
+#error "Environments where CHAR_BIT != 8 are not supported."
+#endif
+
+
+namespace {
+
+#ifdef O_BINARY
+const int o_binary = O_BINARY;
+#else
+const int o_binary = 0;
+#endif
+
+
+void show_zupdate_help()
+ {
+ std::printf( "Zupdate recompresses files from bzip2, gzip, and xz formats to lzip format.\n"
+ "The originals are compared with the new files and then deleted.\n"
+ "Only regular files with standard file name extensions are recompressed,\n"
+ "other files are ignored.\n"
+ "Compressed files are decompressed and then recompressed on the fly; no\n"
+ "temporary files are created.\n"
+ "The lzip format is chosen as destination because it is by far the most\n"
+ "appropriate for long-term data archiving.\n"
+ "\nIf the lzip compressed version of a file already exists, the file is\n"
+ "skipped unless the '--force' option is given. In this case, if the\n"
+ "comparison fails, an error is returned and the original file is not\n"
+ "deleted. The operation of zupdate is meant to be safe and not produce\n"
+ "any data loss. Therefore, existing lzip compressed files are never\n"
+ "overwritten nor deleted.\n"
+ "\nUsage: zupdate [options] [files]\n"
+ "\nExit status is 0 if all the compressed files were successfully\n"
+ "recompressed (if needed), compared and deleted. Non-zero otherwise.\n"
+ "\nOptions:\n"
+ " -h, --help display this help and exit\n"
+ " -V, --version output version information and exit\n"
+ " -f, --force do not skip a file even if the .lz exists\n"
+ " -l, --lzip-verbose pass a -v option to the lzip compressor\n"
+ " -N, --no-rcfile don't read runtime configuration file\n"
+ " -q, --quiet suppress all messages\n"
+ " -r, --recursive operate recursively on directories\n"
+ " -v, --verbose be verbose (a 2nd -v gives more)\n"
+ " -0 .. -9 set compression level [default 9]\n"
+ " --bz2=<command> set compressor and options for bzip2 format\n"
+ " --gz=<command> set compressor and options for gzip format\n"
+ " --lz=<command> set compressor and options for lzip format\n"
+ " --xz=<command> set compressor and options for xz format\n" );
+ show_help_addr();
+ }
+
+
+int cant_execute( const std::string & command, const int status )
+ {
+ if( verbosity >= 0 )
+ {
+ if( WIFEXITED( status ) )
+ std::fprintf( stderr, "%s: Error executing '%s'. Exit status = %d.\n",
+ util_name, command.c_str(), WEXITSTATUS( status ) );
+ else
+ std::fprintf( stderr, "%s: Can't execute '%s'.\n",
+ util_name, command.c_str() );
+ }
+ return 1;
+ }
+
+
+ // Set permissions, owner and times.
+void set_permissions( const char * const rname, const struct stat & in_stats )
+ {
+ bool warning = false;
+ // fchown will in many cases return with EPERM, which can be safely ignored.
+ if( ( chown( rname, in_stats.st_uid, in_stats.st_gid ) != 0 &&
+ errno != EPERM ) ||
+ chmod( rname, in_stats.st_mode ) != 0 ) warning = true;
+ struct utimbuf t;
+ t.actime = in_stats.st_atime;
+ t.modtime = in_stats.st_mtime;
+ if( utime( rname, &t ) != 0 ) warning = true;
+ if( warning && verbosity >= 2 )
+ show_error( "Can't change output file attributes." );
+ }
+
+
+struct { const char * from; const char * to; int format_index; } const
+ known_extensions[] = {
+ { ".bz2", "", fmt_bz2 },
+ { ".tbz", ".tar", fmt_bz2 },
+ { ".tbz2", ".tar", fmt_bz2 },
+ { ".gz", "", fmt_gz },
+ { ".tgz", ".tar", fmt_gz },
+ { ".lz", "", fmt_lz },
+ { ".tlz", ".tar", fmt_lz },
+ { ".xz", "", fmt_xz },
+ { ".txz", ".tar", fmt_xz },
+ { 0, 0, -1 } };
+
+
+ // Returns 0 for success, -1 for file skipped, 1 for error.
+int zupdate_file( const std::string & name, const char * const lzip_name,
+ const std::vector< std::string > & lzip_args2,
+ const bool force )
+ {
+ int format_index = -1;
+ std::string dname; // decompressed_name
+
+ for( int i = 0; known_extensions[i].from; ++i ) // search extension
+ {
+ const std::string from( known_extensions[i].from );
+ if( name.size() > from.size() &&
+ name.compare( name.size() - from.size(), from.size(), from ) == 0 )
+ {
+ dname.assign( name, 0, name.size() - from.size() );
+ dname += known_extensions[i].to;
+ format_index = known_extensions[i].format_index;
+ if( format_index == fmt_lz )
+ {
+ if( verbosity >= 2 )
+ std::fprintf( stderr, "%s: Input file '%s' already has '%s' suffix.\n",
+ util_name, name.c_str(), known_extensions[i].from );
+ return 0; // ignore this file
+ }
+ break;
+ }
+ }
+ const char * const compressor_name = get_compressor_name( format_index );
+ if( !compressor_name || !compressor_name[0] )
+ {
+ if( verbosity >= 2 )
+ std::fprintf( stderr, "%s: Unknown extension in file name '%s' -- ignored.\n",
+ util_name, name.c_str() );
+ return 0; // ignore this file
+ }
+
+ struct stat in_stats;
+ if( stat( name.c_str(), &in_stats ) != 0 ) // check input file
+ {
+ if( verbosity >= 0 )
+ std::fprintf( stderr, "%s: Can't stat input file '%s': %s.\n",
+ util_name, name.c_str(), std::strerror( errno ) );
+ return 1;
+ }
+ if( !S_ISREG( in_stats.st_mode ) )
+ {
+ if( verbosity >= 0 )
+ std::fprintf( stderr, "%s: Input file '%s' is not a regular file.\n",
+ util_name, name.c_str() );
+ return 1;
+ }
+
+ struct stat st;
+ std::string rname( dname ); rname += ".lz"; // recompressed_name
+ const bool lz_exists = ( stat( rname.c_str(), &st ) == 0 );
+ if( lz_exists && !force )
+ {
+ if( verbosity >= 0 )
+ std::fprintf( stderr, "%s: Output file '%s' already exists, skipping.\n",
+ util_name, rname.c_str() );
+ return -1;
+ }
+
+ if( !lz_exists ) // recompress
+ {
+ if( verbosity >= 1 )
+ std::fprintf( stderr, "Recompressing file '%s'.\n", name.c_str() );
+ int fda[2]; // pipe between decompressor and compressor
+ if( pipe( fda ) < 0 )
+ { show_error( "Can't create pipe", errno ); return 1; }
+
+ const pid_t pid = fork();
+ if( pid == 0 ) // child1 (decompressor)
+ {
+ if( dup2( fda[1], STDOUT_FILENO ) >= 0 &&
+ close( fda[0] ) == 0 && close( fda[1] ) == 0 )
+ {
+ const std::vector< std::string > & compressor_args =
+ get_compressor_args( format_index );
+ const int size = compressor_args.size();
+ const char ** const argv = new const char *[size+5];
+ argv[0] = compressor_name;
+ for( int i = 0; i < size; ++i ) argv[i+1] = compressor_args[i].c_str();
+ argv[size+1] = "-cd";
+ argv[size+2] = "--";
+ argv[size+3] = name.c_str();
+ argv[size+4] = 0;
+ execvp( argv[0], (char **)argv );
+ }
+ show_exec_error( compressor_name );
+ _exit( 1 );
+ }
+ if( pid < 0 ) // parent
+ { show_fork_error( compressor_name ); return 1; }
+
+ const pid_t pid2 = fork();
+ if( pid2 == 0 ) // child2 (lzip compressor)
+ {
+ if( dup2( fda[0], STDIN_FILENO ) >= 0 &&
+ close( fda[0] ) == 0 && close( fda[1] ) == 0 )
+ {
+ const std::vector< std::string > & lzip_args =
+ get_compressor_args( fmt_lz );
+ const int size = lzip_args.size();
+ const int size2 = lzip_args2.size();
+ const char ** const argv = new const char *[size+size2+5];
+ argv[0] = lzip_name;
+ argv[1] = "-9";
+ for( int i = 0; i < size; ++i ) argv[i+2] = lzip_args[i].c_str();
+ for( int i = 0; i < size2; ++i ) argv[i+size+2] = lzip_args2[i].c_str();
+ argv[size+size2+2] = "-o";
+ argv[size+size2+3] = dname.c_str();
+ argv[size+size2+4] = 0;
+ execvp( argv[0], (char **)argv );
+ }
+ show_exec_error( lzip_name );
+ _exit( 1 );
+ }
+ if( pid2 < 0 ) // parent
+ { show_fork_error( lzip_name ); return 1; }
+
+ close( fda[0] ); close( fda[1] );
+ int retval = wait_for_child( pid, compressor_name );
+ int retval2 = wait_for_child( pid2, lzip_name );
+ if( retval || retval2 ) { std::remove( rname.c_str() ); return 1; }
+ set_permissions( rname.c_str(), in_stats );
+ }
+
+ {
+ if( lz_exists && verbosity >= 1 )
+ std::fprintf( stderr, "Comparing file '%s'.\n", name.c_str() );
+ std::string zcmp_command( invocation_name );
+ unsigned i = zcmp_command.size();
+ while( i > 0 && zcmp_command[i-1] != '/' ) --i;
+ zcmp_command.resize( i );
+ zcmp_command += "zcmp "; // ${bindir}zcmp
+ zcmp_command += name; zcmp_command += ' '; zcmp_command += rname;
+ int status = std::system( zcmp_command.c_str() );
+ if( status != 0 )
+ { if( !lz_exists ) std::remove( rname.c_str() );
+ return cant_execute( zcmp_command, status ); }
+ }
+
+ if( std::remove( name.c_str() ) != 0 && errno != ENOENT )
+ {
+ if( verbosity >= 0 )
+ std::fprintf( stderr, "%s: Can't delete input file '%s': %s.\n",
+ util_name, name.c_str(), std::strerror( errno ) );
+ return 1;
+ }
+ return 0;
+ }
+
+} // end namespace
+
+
+int main( const int argc, const char * const argv[] )
+ {
+ enum { bz2_opt = 256, gz_opt, lz_opt, xz_opt };
+ std::string input_filename;
+ std::list< std::string > filenames;
+ std::vector< std::string > lzip_args2; // args to lzip, maybe empty
+ bool force = false;
+ bool recursive = false;
+ invocation_name = argv[0];
+ util_name = "zupdate";
+
+ const Arg_parser::Option options[] =
+ {
+ { '0', 0, Arg_parser::no },
+ { '1', 0, Arg_parser::no },
+ { '2', 0, Arg_parser::no },
+ { '3', 0, Arg_parser::no },
+ { '4', 0, Arg_parser::no },
+ { '5', 0, Arg_parser::no },
+ { '6', 0, Arg_parser::no },
+ { '7', 0, Arg_parser::no },
+ { '8', 0, Arg_parser::no },
+ { '9', 0, Arg_parser::no },
+ { 'f', "force", Arg_parser::no },
+ { 'h', "help", Arg_parser::no },
+ { 'l', "lzip-verbose", Arg_parser::no },
+ { 'N', "no-rcfile", Arg_parser::no },
+ { 'q', "quiet", Arg_parser::no },
+ { 'r', "recursive", Arg_parser::no },
+ { 'v', "verbose", Arg_parser::no },
+ { 'V', "version", Arg_parser::no },
+ { bz2_opt, "bz2", Arg_parser::yes },
+ { gz_opt, "gz", Arg_parser::yes },
+ { lz_opt, "lz", Arg_parser::yes },
+ { xz_opt, "xz", Arg_parser::yes },
+ { 0 , 0, Arg_parser::no } };
+
+ const Arg_parser parser( argc, argv, options );
+ if( parser.error().size() ) // bad option
+ { show_error( parser.error().c_str(), 0, true ); return 1; }
+
+ maybe_process_config_file( parser );
+
+ int argind = 0;
+ for( ; argind < parser.arguments(); ++argind )
+ {
+ const int code = parser.code( argind );
+ if( !code ) break; // no more options
+ const char * const arg = parser.argument( argind ).c_str();
+ switch( code ) // common options
+ {
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ lzip_args2.push_back( "-" ); lzip_args2.back() += code; break;
+ case 'f': force = true; break;
+ case 'h': show_zupdate_help(); return 0;
+ case 'l': lzip_args2.push_back( "-v" ); break;
+ case 'N': continue;
+ case 'q': verbosity = -1; lzip_args2.push_back( "-q" ); break;
+ case 'r': recursive = true; break;
+ case 'v': if( verbosity < 4 ) ++verbosity; break;
+ case 'V': show_version( "Zupdate" ); return 0;
+ case bz2_opt: parse_compressor( arg, fmt_bz2, 1 ); continue;
+ case gz_opt: parse_compressor( arg, fmt_gz, 1 ); continue;
+ case lz_opt: parse_compressor( arg, fmt_lz, 1 ); continue;
+ case xz_opt: parse_compressor( arg, fmt_xz, 1 ); continue;
+ default : internal_error( "uncaught option" );
+ }
+ } // end process options
+
+#if defined(__MSVCRT__) || defined(__OS2__)
+ setmode( STDIN_FILENO, O_BINARY );
+ setmode( STDOUT_FILENO, O_BINARY );
+#endif
+
+ const char * const lzip_name = get_compressor_name( fmt_lz );
+ if( !lzip_name || !lzip_name[0] )
+ { show_error( "Missing name of compressor for lzip format." ); return 1; }
+
+ for( ; argind < parser.arguments(); ++argind )
+ filenames.push_back( parser.argument( argind ) );
+
+ int retval = 0;
+ while( !filenames.empty() )
+ {
+ input_filename = filenames.front();
+ filenames.pop_front();
+ if( !input_filename.size() || input_filename == "-" ) continue;
+ if( recursive )
+ {
+ struct stat st;
+ if( stat( input_filename.c_str(), &st ) == 0 && S_ISDIR( st.st_mode ) )
+ {
+ DIR * const dirp = opendir( input_filename.c_str() );
+ if( !dirp )
+ {
+ show_error2( "Can't open directory", input_filename.c_str() );
+ if( retval < 1 ) retval = 1; continue;
+ }
+ std::list< std::string > tmp_list;
+ while( true )
+ {
+ const struct dirent * const entryp = readdir( dirp );
+ if( !entryp ) { closedir( dirp ); break; }
+ std::string tmp_name( entryp->d_name );
+ if( tmp_name != "." && tmp_name != ".." )
+ tmp_list.push_back( input_filename + "/" + tmp_name );
+ }
+ filenames.splice( filenames.begin(), tmp_list );
+ continue;
+ }
+ }
+
+ int tmp = zupdate_file( input_filename, lzip_name, lzip_args2, force );
+ if( tmp < 0 && retval < 1 ) retval = 1;
+ if( tmp > retval ) retval = tmp;
+ if( tmp > 0 ) break;
+ }
+ return retval;
+ }