gtkradiant/tools/urt/libs/versionlib.h

#if !defined( INCLUDED_VERSIONLIB_H )
#define INCLUDED_VERSIONLIB_H

#include <cstddef>
#include <string.h>
#include <algorithm>

class Version
{
public:
int major;
int minor;
};

inline bool operator<( const Version& version, const Version& other ){
	return version.major < other.major || ( !( other.major < version.major ) && version.minor < other.minor );
}

template<typename TextOutputStreamType>
TextOutputStreamType& ostream_write( TextOutputStreamType& outputStream, const Version& version ){
	return outputStream << version.major << '.' << version.minor;
}

/// \brief Returns true if \p version (code) is compatible with \p other (data).
inline bool version_compatible( const Version& version, const Version& other ){
	return version.major == other.major // different major-versions are always incompatible
		   && !( version.minor < other.minor ); // data minor-version is incompatible if greater than code minor-version
}

inline int string_range_parse_int( const char* first, const char* last ){
	const std::size_t bufferSize = 32;
	char buffer[bufferSize];
	strncpy( buffer, first, std::min( std::size_t( last - first ), bufferSize - 1 ) );
	buffer[bufferSize - 1] = '\0';
	return atoi( buffer );
}

inline Version version_parse( const char* versionString ){
	Version version;
	const char* endVersion = versionString + strlen( versionString );

	const char* endMajor = strchr( versionString, '.' );
	if ( endMajor == 0 ) {
		endMajor = endVersion;

		version.minor = 0;
	}
	else
	{
		const char* endMinor = strchr( endMajor + 1, '.' );
		if ( endMinor == 0 ) {
			endMinor = endVersion;
		}
		version.minor = string_range_parse_int( endMajor + 1, endMinor );
	}
	version.major = string_range_parse_int( versionString, endMajor );

	return version;
}

#endif