banan-os/kernel/kernel/FS/RamFS/Inode.cpp

282 lines
6.7 KiB
C++

#include <kernel/FS/RamFS/FileSystem.h>
#include <kernel/FS/RamFS/Inode.h>
#include <kernel/Timer/Timer.h>
namespace Kernel
{
RamInode::FullInodeInfo::FullInodeInfo(RamFileSystem& fs, mode_t mode, uid_t uid, gid_t gid)
{
timespec current_time = SystemTimer::get().real_time();
this->ino = fs.next_ino();
this->mode = mode;
this->nlink = 1;
this->uid = uid;
this->gid = gid;
this->size = 0;
this->atime = current_time;
this->mtime = current_time;
this->ctime = current_time;
this->blksize = fs.blksize();
this->blocks = 0;
// TODO
this->dev = 0;
this->rdev = 0;
}
/*
RAM FILE INODE
*/
BAN::ErrorOr<BAN::RefPtr<RamFileInode>> RamFileInode::create(RamFileSystem& fs, mode_t mode, uid_t uid, gid_t gid)
{
FullInodeInfo inode_info(fs, mode, uid, gid);
auto* ram_inode = new RamFileInode(fs, inode_info);
if (ram_inode == nullptr)
return BAN::Error::from_errno(ENOMEM);
return BAN::RefPtr<RamFileInode>::adopt(ram_inode);
}
RamFileInode::RamFileInode(RamFileSystem& fs, const FullInodeInfo& inode_info)
: RamInode(fs, inode_info)
{
m_inode_info.mode |= Inode::Mode::IFREG;
}
BAN::ErrorOr<size_t> RamFileInode::read_impl(off_t offset, void* buffer, size_t bytes)
{
ASSERT(offset >= 0);
if (offset >= size())
return 0;
size_t to_copy = BAN::Math::min<size_t>(m_inode_info.size - offset, bytes);
memcpy(buffer, m_data.data(), to_copy);
return to_copy;
}
BAN::ErrorOr<size_t> RamFileInode::write_impl(off_t offset, const void* buffer, size_t bytes)
{
ASSERT(offset >= 0);
if (offset + bytes > (size_t)size())
TRY(truncate_impl(offset + bytes));
memcpy(m_data.data() + offset, buffer, bytes);
return bytes;
}
BAN::ErrorOr<void> RamFileInode::truncate_impl(size_t new_size)
{
TRY(m_data.resize(new_size, 0));
m_inode_info.size = m_data.size();
m_inode_info.blocks = BAN::Math::div_round_up<size_t>(size(), blksize());
return {};
}
/*
RAM DIRECTORY INODE
*/
BAN::ErrorOr<BAN::RefPtr<RamDirectoryInode>> RamDirectoryInode::create(RamFileSystem& fs, ino_t parent, mode_t mode, uid_t uid, gid_t gid)
{
FullInodeInfo inode_info(fs, mode, uid, gid);
// "." links to this
inode_info.nlink++;
// ".." links to this or parent
if (parent)
TRY(fs.get_inode(parent))->add_link();
else
{
inode_info.nlink++;
parent = inode_info.ino;
}
auto* ram_inode = new RamDirectoryInode(fs, inode_info, parent);
if (ram_inode == nullptr)
return BAN::Error::from_errno(ENOMEM);
return BAN::RefPtr<RamDirectoryInode>::adopt(ram_inode);
}
RamDirectoryInode::RamDirectoryInode(RamFileSystem& fs, const FullInodeInfo& inode_info, ino_t parent)
: RamInode(fs, inode_info)
, m_parent(parent)
{
m_inode_info.mode |= Inode::Mode::IFDIR;
}
BAN::ErrorOr<BAN::RefPtr<Inode>> RamDirectoryInode::find_inode_impl(BAN::StringView name)
{
if (name == "."sv)
{
BAN::RefPtr<Inode> inode = TRY(m_fs.get_inode(ino()));
return inode;
}
if (name == ".."sv)
{
BAN::RefPtr<Inode> inode = TRY(m_fs.get_inode(m_parent));
return inode;
}
for (const auto& entry : m_entries)
{
if (name == entry.name)
{
BAN::RefPtr<Inode> inode = TRY(m_fs.get_inode(entry.ino));
return inode;
}
}
return BAN::Error::from_errno(ENOENT);
}
BAN::ErrorOr<void> RamDirectoryInode::list_next_inodes_impl(off_t offset, DirectoryEntryList* list, size_t list_size)
{
ASSERT(offset >= 0);
// TODO: don't require memory for all entries on single call
if (offset != 0)
{
list->entry_count = 0;
return {};
}
size_t needed_size = sizeof(DirectoryEntryList);
needed_size += sizeof(DirectoryEntry) + 2; // "."
needed_size += sizeof(DirectoryEntry) + 3; // ".."
for (auto& entry : m_entries)
needed_size += sizeof(DirectoryEntry) + entry.name_len + 1;
if (needed_size > list_size)
return BAN::Error::from_errno(EINVAL);
DirectoryEntry* ptr = list->array;
// "."
{
ptr->dirent.d_ino = ino();
ptr->rec_len = sizeof(DirectoryEntry) + 2;
strcpy(ptr->dirent.d_name, ".");
ptr = ptr->next();
}
// ".."
{
ptr->dirent.d_ino = m_parent;
ptr->rec_len = sizeof(DirectoryEntry) + 3;
strcpy(ptr->dirent.d_name, "..");
ptr = ptr->next();
}
for (auto& entry : m_entries)
{
ptr->dirent.d_ino = entry.ino;
ptr->rec_len = sizeof(DirectoryEntry) + entry.name_len + 1;
strcpy(ptr->dirent.d_name, entry.name);
ptr = ptr->next();
}
list->entry_count = m_entries.size() + 2;
return {};
}
BAN::ErrorOr<void> RamDirectoryInode::create_file_impl(BAN::StringView name, mode_t mode, uid_t uid, gid_t gid)
{
BAN::RefPtr<RamInode> inode;
if (Mode(mode).ifreg())
inode = TRY(RamFileInode::create(m_fs, mode, uid, gid));
else if (Mode(mode).ifdir())
inode = TRY(RamDirectoryInode::create(m_fs, ino(), mode, uid, gid));
else
ASSERT_NOT_REACHED();
TRY(add_inode(name, inode));
return {};
}
BAN::ErrorOr<void> RamDirectoryInode::add_inode(BAN::StringView name, BAN::RefPtr<RamInode> inode)
{
if (name.size() > m_name_max)
return BAN::Error::from_errno(ENAMETOOLONG);
for (auto& entry : m_entries)
if (name == entry.name)
return BAN::Error::from_errno(EEXIST);
TRY(m_entries.push_back({ }));
Entry& entry = m_entries.back();
strcpy(entry.name, name.data());
entry.name_len = name.size();
entry.ino = inode->ino();
if (auto ret = m_fs.add_inode(inode); ret.is_error())
{
m_entries.pop_back();
return ret.release_error();
}
return {};
}
BAN::ErrorOr<void> RamDirectoryInode::delete_inode_impl(BAN::StringView name)
{
for (size_t i = 0; i < m_entries.size(); i++)
{
if (name == m_entries[i].name)
{
m_entries.remove(i);
return {};
}
}
return BAN::Error::from_errno(ENOENT);
}
/*
RAM SYMLINK INODE
*/
BAN::ErrorOr<BAN::RefPtr<RamSymlinkInode>> RamSymlinkInode::create(RamFileSystem& fs, BAN::StringView target_sv, mode_t mode, uid_t uid, gid_t gid)
{
FullInodeInfo inode_info(fs, mode, uid, gid);
BAN::String target_str;
TRY(target_str.append(target_sv));
auto* ram_inode = new RamSymlinkInode(fs, inode_info, BAN::move(target_str));
if (ram_inode == nullptr)
return BAN::Error::from_errno(ENOMEM);
return BAN::RefPtr<RamSymlinkInode>::adopt(ram_inode);
}
RamSymlinkInode::RamSymlinkInode(RamFileSystem& fs, const FullInodeInfo& inode_info, BAN::String&& target)
: RamInode(fs, inode_info)
, m_target(BAN::move(target))
{
m_inode_info.mode |= Inode::Mode::IFLNK;
}
BAN::ErrorOr<BAN::String> RamSymlinkInode::link_target_impl()
{
BAN::String result;
TRY(result.append(m_target));
return result;
}
BAN::ErrorOr<void> RamSymlinkInode::set_link_target(BAN::StringView target)
{
BAN::String temp;
TRY(temp.append(target));
m_target = BAN::move(temp);
return {};
}
}