Generic Image Library : io_error.hpp Source File

00001 /*
00002     Copyright 2005-2007 Adobe Systems Incorporated
00003    
00004     Use, modification and distribution are subject to the Boost Software License,
00005     Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
00006     http://www.boost.org/LICENSE_1_0.txt).
00007 
00008     See http://opensource.adobe.com/gil for most recent version including documentation.
00009 */
00010 /*************************************************************************************************/
00011 
00012 #ifndef GIL_IO_ERROR_H
00013 #define GIL_IO_ERROR_H
00014 
00020 
00021 #include <ios>
00022 #include "../../gil_config.hpp"
00023 #include <boost/shared_ptr.hpp>
00024 
00025 namespace boost { namespace gil {
00026 
00027 inline void io_error(const char* descr) { throw std::ios_base::failure(descr); }
00028 inline void io_error_if(bool expr, const char* descr="") { if (expr) io_error(descr); }
00029 
00030 namespace detail {
00031     class file_mgr {
00032     protected:
00033         shared_ptr<FILE> _fp;
00034 
00035         struct null_deleter { void operator()(void const*) const {} };
00036         file_mgr(FILE* file) : _fp(file, null_deleter()) {}
00037 
00038         file_mgr(const char* filename, const char* flags) {
00039             FILE* fp;
00040             io_error_if((fp=fopen(filename,flags))==NULL, "file_mgr: failed to open file");
00041             _fp=shared_ptr<FILE>(fp,fclose);
00042         }
00043 
00044     public:
00045         FILE* get() { return _fp.get(); }
00046     };
00047 }
00048 
00049 } }  // namespace boost::gil
00050 
00051 #endif