123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209 |
- //Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc.
- //Distributed under the Boost Software License, Version 1.0. (See accompanying
- //file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
- //This program simulates errors on copying simple data files. It demonstrates
- //typical Boost Exception usage.
- //The output from this program can vary depending on the platform.
- #include <boost/throw_exception.hpp>
- #include <boost/exception/info.hpp>
- #include <boost/exception/get_error_info.hpp>
- #include <boost/exception/diagnostic_information.hpp>
- #include <boost/exception/errinfo_file_open_mode.hpp>
- #include <boost/exception/errinfo_file_handle.hpp>
- #include <boost/exception/errinfo_file_name.hpp>
- #include <boost/exception/errinfo_api_function.hpp>
- #include <boost/exception/errinfo_errno.hpp>
- #include <boost/shared_ptr.hpp>
- #include <boost/weak_ptr.hpp>
- #include <iostream>
- typedef boost::error_info<struct tag_file_name_src,std::string> errinfo_src_file_name;
- typedef boost::error_info<struct tag_file_name_dst,std::string> errinfo_dst_file_name;
- char const data[] = "example";
- size_t const data_size = sizeof(data);
- class
- error: //Base for all exception objects we throw.
- public virtual std::exception,
- public virtual boost::exception
- {
- public:
- char const *
- what() const BOOST_NOEXCEPT_OR_NOTHROW
- {
- return "example_io error";
- }
- protected:
- ~error() BOOST_NOEXCEPT_OR_NOTHROW
- {
- }
- };
- struct open_error: virtual error { };
- struct read_error: virtual error { };
- struct write_error: virtual error { };
- struct fopen_error: virtual open_error { };
- struct fread_error: virtual read_error { };
- struct fwrite_error: virtual write_error { };
- boost::shared_ptr<FILE>
- my_fopen( char const * name, char const * mode )
- {
- if( FILE * f = ::fopen(name,mode) )
- return boost::shared_ptr<FILE>(f,fclose);
- else
- BOOST_THROW_EXCEPTION(fopen_error() <<
- boost::errinfo_errno (errno) <<
- boost::errinfo_file_name(name) <<
- boost::errinfo_file_open_mode(mode) <<
- boost::errinfo_api_function("fopen"));
- }
- void
- my_fread( void * buffer, size_t size, size_t count, boost::shared_ptr<FILE> const & stream )
- {
- assert(stream);
- if( count!=fread(buffer,size,count,stream.get()) || ferror(stream.get()) )
- BOOST_THROW_EXCEPTION(fread_error() <<
- boost::errinfo_api_function("fread") <<
- boost::errinfo_errno(errno) <<
- boost::errinfo_file_handle(boost::weak_ptr<FILE>(stream)));
- }
- void
- my_fwrite( void const * buffer, size_t size, size_t count, boost::shared_ptr<FILE> const & stream )
- {
- assert(stream);
- if( count!=fwrite(buffer,size,count,stream.get()) || ferror(stream.get()) )
- BOOST_THROW_EXCEPTION(fwrite_error() <<
- boost::errinfo_api_function("fwrite") <<
- boost::errinfo_errno(errno) <<
- boost::errinfo_file_handle(boost::weak_ptr<FILE>(stream)));
- }
- void
- reset_file( char const * file_name )
- {
- (void) my_fopen(file_name,"wb");
- }
- void
- create_data( char const * file_name )
- {
- boost::shared_ptr<FILE> f = my_fopen(file_name,"wb");
- my_fwrite( data, 1, data_size, f );
- }
- void
- copy_data( char const * src_file_name, char const * dst_file_name )
- {
- boost::shared_ptr<FILE> src = my_fopen(src_file_name,"rb");
- boost::shared_ptr<FILE> dst = my_fopen(dst_file_name,"wb");
- try
- {
- char buffer[data_size];
- my_fread( buffer, 1, data_size, src );
- my_fwrite( buffer, 1, data_size, dst );
- }
- catch(
- boost::exception & x )
- {
- if( boost::weak_ptr<FILE> const * f=boost::get_error_info<boost::errinfo_file_handle>(x) )
- if( boost::shared_ptr<FILE> fs = f->lock() )
- {
- if( fs==src )
- x << boost::errinfo_file_name(src_file_name);
- else if( fs==dst )
- x << boost::errinfo_file_name(dst_file_name);
- }
- x <<
- errinfo_src_file_name(src_file_name) <<
- errinfo_dst_file_name(dst_file_name);
- throw;
- }
- }
- void
- dump_copy_info( boost::exception const & x )
- {
- if( std::string const * src = boost::get_error_info<errinfo_src_file_name>(x) )
- std::cerr << "Source file name: " << *src << "\n";
- if( std::string const * dst = boost::get_error_info<errinfo_dst_file_name>(x) )
- std::cerr << "Destination file name: " << *dst << "\n";
- }
- void
- dump_file_info( boost::exception const & x )
- {
- if( std::string const * fn = boost::get_error_info<boost::errinfo_file_name>(x) )
- std::cerr << "File name: " << *fn << "\n";
- }
- void
- dump_clib_info( boost::exception const & x )
- {
- if( int const * err=boost::get_error_info<boost::errinfo_errno>(x) )
- std::cerr << "OS error: " << *err << "\n";
- if( char const * const * fn=boost::get_error_info<boost::errinfo_api_function>(x) )
- std::cerr << "Failed function: " << *fn << "\n";
- }
- void
- dump_all_info( boost::exception const & x )
- {
- std::cerr << "-------------------------------------------------\n";
- dump_copy_info(x);
- dump_file_info(x);
- dump_clib_info(x);
- std::cerr << "\nOutput from diagnostic_information():\n";
- std::cerr << diagnostic_information(x);
- }
- int
- main()
- {
- try
- {
- create_data( "tmp1.txt" );
- copy_data( "tmp1.txt", "tmp2.txt" ); //This should succeed.
- reset_file( "tmp1.txt" ); //Creates empty file.
- try
- {
- copy_data( "tmp1.txt", "tmp2.txt" ); //This should fail, tmp1.txt is empty.
- }
- catch(
- read_error & x )
- {
- std::cerr << "\nCaught 'read_error' exception.\n";
- dump_all_info(x);
- }
- remove( "tmp1.txt" );
- remove( "tmp2.txt" );
- try
- {
- copy_data( "tmp1.txt", "tmp2.txt" ); //This should fail, tmp1.txt does not exist.
- }
- catch(
- open_error & x )
- {
- std::cerr << "\nCaught 'open_error' exception.\n";
- dump_all_info(x);
- }
- }
- catch(
- ... )
- {
- std::cerr << "\nCaught unexpected exception!\n";
- std::cerr << boost::current_exception_diagnostic_information();
- }
- }
|