MaxOS::filesystem::FileResource Class Reference

A wrapper for a File which exposes File operations as Resource operations. More...

#include <vfsresource.h>

Inheritance diagram for MaxOS::filesystem::FileResource:

Public Member Functions
	FileResource (const string &name, size_t flags, processes::resource_type_t type)
	Construct a new File Resource object.
int	read (void *buffer, size_t size, size_t flags) final
	read from a file resource
int	write (const void *buffer, size_t size, size_t flags) final
	write to a file resource
Public Member Functions inherited from MaxOS::processes::Resource
	Resource (const string &name, size_t flags, resource_type_t type)
	Constructs a new Resource object.
string	name ()
	Gets the name of this resource.
resource_type_t	type ()
	Gets the type of this resource.
virtual void	open (size_t flags)
	Opens the resource.
virtual void	close (size_t flags)
	Closes the resource.

Public Attributes
File *	file
	The file that this resource handles & exposes.

Detailed Description

A wrapper for a File which exposes File operations as Resource operations.

See also

File

Resource

Todo:

Should this free the memory of the file when the resource is done??

Definition at line 32 of file vfsresource.h.

Constructor & Destructor Documentation

FileResource()

FileResource::FileResource	(	const string &	name,
		size_t	flags,
		processes::resource_type_t	type
	)

Construct a new File Resource object.

Parameters

name	The name of the resource
flags	The flags for the resource when opened
type	The type of the resource

Definition at line 24 of file vfsresource.cpp.

: Resource(name, flags, type),
  file(nullptr) // Initialised by the registry
{
 
}

Member Function Documentation

read()

int FileResource::read ( void *  buffer, size_t  size, size_t  flags  )

finalvirtual

read from a file resource

Parameters

buffer	The buffer to read into
size	The number of bytes to read
flags	The flags to pass to the reading

Returns

The number of bytes successfully read or -1 on error

Reimplemented from MaxOS::processes::Resource.

Definition at line 41 of file vfsresource.cpp.

                                                              {
 
    // File not found
    if(!file)
        return -1;
 
    // Handle the operation
    switch ((FileFlags)flags) {
 
        case FileFlags::DEFAULT:{
 
            buffer_t file_buffer(buffer, size);
            file->read(&file_buffer, size);
            break;
        }
 
        case FileFlags::READ_SIZE:{
            return file->size();
        }
 
        case FileFlags::READ_OFFSET:{
 
            return file->position();
        }
 
        default:
            return -1;
    }
    return size;
}

References file, MaxOS::filesystem::File::position(), MaxOS::filesystem::File::read(), and MaxOS::filesystem::File::size().

write()

int FileResource::write ( const void *  buffer, size_t  size, size_t  flags  )

finalvirtual

write to a file resource

Parameters

buffer	The buffer to write from
size	The number of bytes to write
flags	The flags to pass to the writing

Returns

The number of bytes successfully written or -1 on error

Reimplemented from MaxOS::processes::Resource.

Definition at line 80 of file vfsresource.cpp.

                                                                     {
 
    // File not found
    if(!file)
        return -1;
 
    // Handle the operation
    switch ((FileFlags)flags) {
        case FileFlags::DEFAULT:{
 
            buffer_t file_buffer((void*)buffer, size);
            file->write(&file_buffer, size);
            break;
        }
 
        case FileFlags::WRITE_SEEK_SET:
            file->seek(SeekType::SET, size);
            break;
 
        case FileFlags::WRITE_SEEK_CUR:
            file->seek(SeekType::CURRENT, size);
            break;
 
        case FileFlags::WRITE_SEEK_END:
            file->seek(SeekType::END, size);
            break;
 
        case FileFlags::WRITE_NAME:{
 
            // Open the parent
            Resource* parent = GlobalResourceRegistry::get_registry(resource_type_t::FILESYSTEM)->get_resource(Path::parent_directory(name()));
            auto parent_directory = ((DirectoryResource*)parent)->directory;
 
            // Rename
            string new_name = string((uint8_t*)buffer, size);
            parent_directory->rename_file(file, new_name);
            break;
        }
 
        default:
            return -1;
 
    }
 
    return size;
}

References file, MaxOS::processes::GlobalResourceRegistry::get_registry(), MaxOS::processes::Resource::name(), MaxOS::filesystem::Path::parent_directory(), MaxOS::filesystem::File::seek(), and MaxOS::filesystem::File::write().

Member Data Documentation

file

File* MaxOS::filesystem::FileResource::file

The file that this resource handles & exposes.

Definition at line 38 of file vfsresource.h.

Referenced by read(), and write().

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The documentation for this class was generated from the following files:

• /home/runner/work/MaxOS/MaxOS/kernel/include/filesystem/vfsresource.h
• /home/runner/work/MaxOS/MaxOS/kernel/src/filesystem/vfsresource.cpp