MaxOS::filesystem::format::ext2::Ext2File Class Reference

Handles the file operations on the ext2 filesystem. More...

#include <ext2.h>

Inheritance diagram for MaxOS::filesystem::format::ext2::Ext2File:

Public Member Functions
	Ext2File (Ext2Volume *volume, uint32_t inode, const string &name)
	Construct a new Ext2 File object.
void	write (common::buffer_t *data, size_t amount) final
	write data to the file (at the current seek position, updated to be += amount)
void	read (common::buffer_t *data, size_t amount) final
	read data from the file (at the current seek position, updated to be += amount)
void	flush () final
	Flush the file to the disk.
Public Member Functions inherited from MaxOS::filesystem::File
void	seek (SeekType seek_type, size_t offset)
	Seek to a position in the file.
uint32_t	position () const
	Get where the file is currently at (amount read/write/seeked)
size_t	size () const
	Get the size of the file.
string	name ()
	Get the name of the file.

Additional Inherited Members
Protected Attributes inherited from MaxOS::filesystem::File
uint32_t	m_offset = 0
	The current offset in the file.
string	m_name
	The name of the file.
size_t	m_size = 0
	The size of the file.

Detailed Description

Handles the file operations on the ext2 filesystem.

Definition at line 402 of file ext2.h.

Constructor & Destructor Documentation

Ext2File()

Ext2File::Ext2File	(	Ext2Volume *	volume,
		uint32_t	inode,
		const string &	name
	)

Construct a new Ext2 File object.

Parameters

volume	The volume the file exists on
inode	The inode number of the file (will be used to setup the internal InodeHandler)
name	The name of the file

Definition at line 725 of file ext2.cpp.

        : m_volume(volume),
        m_inode(volume, inode) {
 
    // Set up the base information
    m_name = name;
    m_size = m_inode.size();
 
}

References MaxOS::filesystem::File::m_name, MaxOS::filesystem::File::m_size, MaxOS::filesystem::File::name(), and MaxOS::filesystem::format::ext2::InodeHandler::size().

Member Function Documentation

flush()

void Ext2File::flush ( )

finalvirtual

Flush the file to the disk.

Reimplemented from MaxOS::filesystem::File.

Definition at line 841 of file ext2.cpp.

                     {
    File::flush();
}

References MaxOS::filesystem::File::flush().

read()

void Ext2File::read ( common::buffer_t *  data, size_t  amount  )

finalvirtual

read data from the file (at the current seek position, updated to be += amount)

Parameters

data	The byte buffer to read into
amount	The amount of data to read

Reimplemented from MaxOS::filesystem::File.

Definition at line 795 of file ext2.cpp.

                                                 {
 
    // Nothing to read
    if(m_size == 0 || amount == 0)
        return;
 
    // Prepare for reading
    m_volume->ext2_lock.lock();
    const uint32_t block_size = m_volume->block_size;
    buffer_t buffer(block_size);
 
    // Force bounds
    if(m_offset + amount > m_size)
        amount = m_size - m_offset;
 
    // Convert bytes to blocks
    uint32_t block_start = m_offset / block_size;
    uint32_t block_offset = m_offset % block_size;
 
    // Read each block
    size_t current_block = block_start;
    size_t read = 0;
    while(read < amount) {
 
        // Read the block
        uint32_t block = m_inode.block_cache[current_block++];
        m_volume->read_block(block, &buffer);
 
        // Where in this block to start reading
        size_t buffer_start = (current_block - 1 == block_start) ? block_offset : 0;
        size_t readable = (amount - read < block_size - buffer_start) ? (amount - read) : (block_size - buffer_start);
 
        // Read the block
        buffer.copy_to(data, readable, buffer_start, read);
        read += readable;
 
    }
 
    // Clean up
    m_offset += amount;
    m_volume->ext2_lock.unlock();
}

References MaxOS::filesystem::format::ext2::InodeHandler::block_cache, MaxOS::filesystem::format::ext2::Ext2Volume::block_size, MaxOS::common::Buffer::copy_to(), MaxOS::filesystem::format::ext2::Ext2Volume::ext2_lock, MaxOS::common::Spinlock::lock(), MaxOS::filesystem::File::m_offset, MaxOS::filesystem::File::m_size, read(), MaxOS::filesystem::format::ext2::Ext2Volume::read_block(), and MaxOS::common::Spinlock::unlock().

Referenced by read().

write()

void Ext2File::write ( common::buffer_t *  data, size_t  amount  )

finalvirtual

write data to the file (at the current seek position, updated to be += amount)

Parameters

data	The byte buffer to write
amount	The amount of data to write

Reimplemented from MaxOS::filesystem::File.

Definition at line 741 of file ext2.cpp.

                                                  {
 
    // Nothing to write
    if(amount == 0)
        return;
 
    // Prepare for writing
    m_volume->ext2_lock.lock();
    const uint32_t block_size = m_volume->block_size;
    buffer_t buffer(block_size);
 
    // Expand the file
    if(m_offset + amount > m_size)
        m_size = m_inode.grow((m_offset + amount) - m_size, false);
 
    // Save the updated metadata
    m_inode.inode.last_modification_time = time_to_epoch(Clock::active_clock()->get_time());
    m_inode.save();
 
    // Convert bytes to blocks
    uint32_t block_start = m_offset / block_size;
    uint32_t block_offset = m_offset % block_size;
 
    // Write each block
    size_t current_block = block_start;
    size_t written = 0;
    while(written < amount) {
 
        // Read the block
        uint32_t block = m_inode.block_cache[current_block++];
        m_volume->read_block(block, &buffer);
 
        // Where in this block to start writing
        size_t buffer_start = (current_block - 1 == block_start) ? block_offset : 0;
        size_t writable = (amount - written < block_size - buffer_start) ? (amount - written) : (block_size -
                                                                                                 buffer_start);
 
        // Update the block
        buffer.copy_from(data, writable, buffer_start, written);
        m_volume->write_block(block, &buffer);
        written += writable;
    }
 
    // Clean up
    m_offset += amount;
    m_volume->ext2_lock.unlock();
}

References MaxOS::drivers::clock::Clock::active_clock(), MaxOS::filesystem::format::ext2::InodeHandler::block_cache, MaxOS::filesystem::format::ext2::Ext2Volume::block_size, MaxOS::common::Buffer::copy_from(), MaxOS::filesystem::format::ext2::Ext2Volume::ext2_lock, MaxOS::filesystem::format::ext2::InodeHandler::grow(), MaxOS::filesystem::format::ext2::InodeHandler::inode, MaxOS::common::Spinlock::lock(), MaxOS::filesystem::File::m_offset, MaxOS::filesystem::File::m_size, MaxOS::filesystem::format::ext2::Ext2Volume::read_block(), MaxOS::filesystem::format::ext2::InodeHandler::save(), MaxOS::common::Spinlock::unlock(), and MaxOS::filesystem::format::ext2::Ext2Volume::write_block().

---

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

• /home/runner/work/MaxOS/MaxOS/kernel/include/filesystem/format/ext2.h
• /home/runner/work/MaxOS/MaxOS/kernel/src/filesystem/format/ext2.cpp