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#include <kernel/filesystem/ext2/inode.hpp>
#include <kernel/filesystem/ext2/filesystem.hpp>
#include <kernel/filesystem/inode.hpp>
#include <kapi/system.hpp>
#include <kstd/cstring>
#include <algorithm>
#include <cstddef>
#include <cstdint>
namespace kernel::filesystem::ext2
{
inode::inode(filesystem * fs, inode_data const & data)
: m_filesystem(fs)
, m_data(data)
{
if (!m_filesystem)
{
kapi::system::panic("[EXT2] ext2::inode constructed with filesystem null pointer");
}
}
auto inode::read(void * buffer, size_t offset, size_t size) const -> size_t
{
// TODO BA-FS26 use revision 1 size
auto const max_readable = static_cast<size_t>(m_data.size) - offset;
auto const requested_size = std::min(size, max_readable);
if (is_symbolic_link() && m_data.size <= sizeof(m_data.block))
{
auto inline_target = reinterpret_cast<uint8_t const *>(m_data.block.data());
kstd::libc::memcpy(static_cast<uint8_t *>(buffer), inline_target + offset, requested_size);
return requested_size;
}
auto block_index = offset / m_filesystem->get_block_size();
auto in_block_offset = offset % m_filesystem->get_block_size();
auto bytes_read = 0uz;
while (bytes_read < size)
{
auto const block_number = m_filesystem->map_inode_block_index_to_global_block_number(block_index, m_data);
// TODO BA-FS26 really correct? sparse files -> 0 means a full block with zeros --> function
// map_inode_block_index_to_global_block_number should return 0 if not possible to find an block
if (block_number == 0)
{
break;
}
auto const block_start_offset = block_number * m_filesystem->get_block_size();
auto const read_offset = block_start_offset + in_block_offset;
auto const bytes_to_read =
std::min(requested_size - bytes_read, m_filesystem->get_block_size() - in_block_offset);
bytes_read +=
m_filesystem->backing_inode()->read(static_cast<uint8_t *>(buffer) + bytes_read, read_offset, bytes_to_read);
block_index++;
in_block_offset = 0; // After the first block, we always start at the beginning of the block
}
return bytes_read;
}
auto inode::write(void const * /*buffer*/, size_t /*offset*/, size_t /*size*/) -> size_t
{
kapi::system::panic("[EXT2] inode::write is not implemented yet");
return 0;
}
[[nodiscard]] auto inode::data() const -> inode_data const &
{
return m_data;
}
auto inode::is_regular() const -> bool
{
return (m_data.mode & constants::mode_mask) == constants::mode_regular;
}
auto inode::is_directory() const -> bool
{
return (m_data.mode & constants::mode_mask) == constants::mode_directory;
}
auto inode::is_symbolic_link() const -> bool
{
return (m_data.mode & constants::mode_mask) == constants::mode_symbolic_link;
}
} // namespace kernel::filesystem::ext2
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