mirror of
https://github.com/DragonOS-Community/DragonOS.git
synced 2025-06-16 01:36:48 +00:00
376 lines
12 KiB
Rust
376 lines
12 KiB
Rust
use core::mem::MaybeUninit;
|
||
|
||
use alloc::{boxed::Box, string::String, sync::Arc, vec::Vec};
|
||
|
||
use crate::{
|
||
arch::asm::current::current_pcb,
|
||
driver::tty::TtyFilePrivateData,
|
||
filesystem::procfs::ProcfsFilePrivateData,
|
||
include::bindings::bindings::{
|
||
process_control_block,
|
||
},
|
||
io::SeekFrom,
|
||
kerror, syscall::SystemError,
|
||
};
|
||
|
||
use super::{Dirent, FileType, IndexNode, Metadata};
|
||
|
||
/// 文件私有信息的枚举类型
|
||
#[derive(Debug, Clone)]
|
||
pub enum FilePrivateData {
|
||
/// procfs文件私有信息
|
||
Procfs(ProcfsFilePrivateData),
|
||
/// Tty设备的私有信息
|
||
Tty(TtyFilePrivateData),
|
||
/// 不需要文件私有信息
|
||
Unused,
|
||
}
|
||
|
||
impl Default for FilePrivateData {
|
||
fn default() -> Self {
|
||
return Self::Unused;
|
||
}
|
||
}
|
||
|
||
bitflags! {
|
||
/// @brief 文件打开模式
|
||
/// 其中，低2bit组合而成的数字的值，用于表示访问权限。其他的bit，才支持通过按位或的方式来表示参数
|
||
///
|
||
/// 与Linux 5.19.10的uapi/asm-generic/fcntl.h相同
|
||
/// https://opengrok.ringotek.cn/xref/linux-5.19.10/tools/include/uapi/asm-generic/fcntl.h#19
|
||
pub struct FileMode: u32{
|
||
/* File access modes for `open' and `fcntl'. */
|
||
/// Open Read-only
|
||
const O_RDONLY = 0o0;
|
||
/// Open Write-only
|
||
const O_WRONLY = 0o1;
|
||
/// Open read/write
|
||
const O_RDWR = 0o2;
|
||
/// Mask for file access modes
|
||
const O_ACCMODE = 0o00000003;
|
||
|
||
/* Bits OR'd into the second argument to open. */
|
||
/// Create file if it does not exist
|
||
const O_CREAT = 0o00000100;
|
||
/// Fail if file already exists
|
||
const O_EXCL = 0o00000200;
|
||
/// Do not assign controlling terminal
|
||
const O_NOCTTY = 0o00000400;
|
||
/// 文件存在且是普通文件，并以O_RDWR或O_WRONLY打开，则它会被清空
|
||
const O_TRUNC = 0o00001000;
|
||
/// 文件指针会被移动到文件末尾
|
||
const O_APPEND = 0o00002000;
|
||
/// 非阻塞式IO模式
|
||
const O_NONBLOCK = 0o00004000;
|
||
/// 每次write都等待物理I/O完成，但是如果写操作不影响读取刚写入的数据，则不等待文件属性更新
|
||
const O_DSYNC = 0o00010000;
|
||
/// fcntl, for BSD compatibility
|
||
const FASYNC = 0o00020000;
|
||
/* direct disk access hint */
|
||
const O_DIRECT = 0o00040000;
|
||
const O_LARGEFILE = 0o00100000;
|
||
/// 打开的必须是一个目录
|
||
const O_DIRECTORY = 0o00200000;
|
||
/// Do not follow symbolic links
|
||
const O_NOFOLLOW = 0o00400000;
|
||
const O_NOATIME = 0o01000000;
|
||
/// set close_on_exec
|
||
const O_CLOEXEC = 0o02000000;
|
||
/// 每次write都等到物理I/O完成，包括write引起的文件属性的更新
|
||
const O_SYNC = 0o04000000;
|
||
}
|
||
}
|
||
|
||
impl FileMode {
|
||
/// @brief 获取文件的访问模式的值
|
||
#[inline]
|
||
pub fn accmode(&self) -> u32 {
|
||
return self.bits() & FileMode::O_ACCMODE.bits();
|
||
}
|
||
}
|
||
/// @brief 抽象文件结构体
|
||
#[derive(Debug)]
|
||
pub struct File {
|
||
inode: Arc<dyn IndexNode>,
|
||
/// 对于文件，表示字节偏移量；对于文件夹，表示当前操作的子目录项偏移量
|
||
offset: usize,
|
||
/// 文件的打开模式
|
||
mode: FileMode,
|
||
/// 文件类型
|
||
file_type: FileType,
|
||
/// readdir时候用的，暂存的本次循环中，所有子目录项的名字的数组
|
||
readdir_subdirs_name: Vec<String>,
|
||
pub private_data: FilePrivateData,
|
||
}
|
||
|
||
impl File {
|
||
/// @brief 创建一个新的文件对象
|
||
///
|
||
/// @param inode 文件对象对应的inode
|
||
/// @param mode 文件的打开模式
|
||
pub fn new(inode: Arc<dyn IndexNode>, mode: FileMode) -> Result<Self, SystemError> {
|
||
let file_type: FileType = inode.metadata()?.file_type;
|
||
let mut f = File {
|
||
inode,
|
||
offset: 0,
|
||
mode,
|
||
file_type,
|
||
readdir_subdirs_name: Vec::new(),
|
||
private_data: FilePrivateData::default(),
|
||
};
|
||
// kdebug!("inode:{:?}",f.inode);
|
||
f.inode.open(&mut f.private_data, &mode)?;
|
||
return Ok(f);
|
||
}
|
||
|
||
/// @brief 从文件中读取指定的字节数到buffer中
|
||
///
|
||
/// @param len 要读取的字节数
|
||
/// @param buf 目标buffer
|
||
///
|
||
/// @return Ok(usize) 成功读取的字节数
|
||
/// @return Err(SystemError) 错误码
|
||
pub fn read(&mut self, len: usize, buf: &mut [u8]) -> Result<usize, SystemError> {
|
||
// 先检查本文件在权限等规则下，是否可读取。
|
||
self.readable()?;
|
||
|
||
if buf.len() < len {
|
||
return Err(SystemError::ENOBUFS);
|
||
}
|
||
let len = self
|
||
.inode
|
||
.read_at(self.offset, len, buf, &mut self.private_data)?;
|
||
self.offset += len;
|
||
return Ok(len);
|
||
}
|
||
|
||
/// @brief 从buffer向文件写入指定的字节数的数据
|
||
///
|
||
/// @param len 要写入的字节数
|
||
/// @param buf 源数据buffer
|
||
///
|
||
/// @return Ok(usize) 成功写入的字节数
|
||
/// @return Err(SystemError) 错误码
|
||
pub fn write(&mut self, len: usize, buf: &[u8]) -> Result<usize, SystemError> {
|
||
// 先检查本文件在权限等规则下，是否可写入。
|
||
self.writeable()?;
|
||
if buf.len() < len {
|
||
return Err(SystemError::ENOBUFS);
|
||
}
|
||
let len = self
|
||
.inode
|
||
.write_at(self.offset, len, buf, &mut self.private_data)?;
|
||
self.offset += len;
|
||
return Ok(len);
|
||
}
|
||
|
||
/// @brief 获取文件的元数据
|
||
pub fn metadata(&self) -> Result<Metadata, SystemError> {
|
||
return self.inode.metadata();
|
||
}
|
||
|
||
/// @brief 根据inode号获取子目录项的名字
|
||
pub fn get_entry_name(&self, ino: usize) -> Result<String, SystemError> {
|
||
return self.inode.get_entry_name(ino);
|
||
}
|
||
|
||
/// @brief 调整文件操作指针的位置
|
||
///
|
||
/// @param origin 调整的起始位置
|
||
pub fn lseek(&mut self, origin: SeekFrom) -> Result<usize, SystemError> {
|
||
if self.inode.metadata().unwrap().file_type == FileType::Pipe {
|
||
return Err(SystemError::ESPIPE);
|
||
}
|
||
let pos: i64;
|
||
match origin {
|
||
SeekFrom::SeekSet(offset) => {
|
||
pos = offset;
|
||
}
|
||
SeekFrom::SeekCurrent(offset) => {
|
||
pos = self.offset as i64 + offset;
|
||
}
|
||
SeekFrom::SeekEnd(offset) => {
|
||
let metadata = self.metadata()?;
|
||
pos = metadata.size + offset;
|
||
}
|
||
SeekFrom::Invalid => {
|
||
return Err(SystemError::EINVAL);
|
||
}
|
||
}
|
||
|
||
if pos < 0 || pos > self.metadata()?.size {
|
||
return Err(SystemError::EOVERFLOW);
|
||
}
|
||
self.offset = pos as usize;
|
||
return Ok(self.offset);
|
||
}
|
||
|
||
/// @brief 判断当前文件是否可读
|
||
#[inline]
|
||
pub fn readable(&self) -> Result<(), SystemError> {
|
||
// 暂时认为只要不是write only, 就可读
|
||
if self.mode == FileMode::O_WRONLY {
|
||
return Err(SystemError::EPERM);
|
||
}
|
||
|
||
return Ok(());
|
||
}
|
||
|
||
/// @brief 判断当前文件是否可写
|
||
#[inline]
|
||
pub fn writeable(&self) -> Result<(), SystemError> {
|
||
// 暂时认为只要不是read only, 就可写
|
||
if self.mode == FileMode::O_RDONLY {
|
||
return Err(SystemError::EPERM);
|
||
}
|
||
|
||
return Ok(());
|
||
}
|
||
|
||
/// @biref 充填dirent结构体
|
||
/// @return 返回dirent结构体的大小
|
||
pub fn readdir(&mut self, dirent: &mut Dirent) -> Result<u64, SystemError> {
|
||
let inode: &Arc<dyn IndexNode> = &self.inode;
|
||
|
||
// 如果偏移量为0
|
||
if self.offset == 0 {
|
||
self.readdir_subdirs_name = inode.list()?;
|
||
self.readdir_subdirs_name.sort();
|
||
}
|
||
|
||
// kdebug!("sub_entries={sub_entries:?}");
|
||
if self.readdir_subdirs_name.is_empty() {
|
||
self.offset = 0;
|
||
return Ok(0);
|
||
}
|
||
let name: String = self.readdir_subdirs_name.remove(0);
|
||
let sub_inode: Arc<dyn IndexNode> = match inode.find(&name) {
|
||
Ok(i) => i,
|
||
Err(e) => {
|
||
kerror!("Readdir error: Failed to find sub inode, file={self:?}");
|
||
return Err(e);
|
||
}
|
||
};
|
||
|
||
let name_bytes: &[u8] = name.as_bytes();
|
||
|
||
self.offset += 1;
|
||
dirent.d_ino = sub_inode.metadata().unwrap().inode_id as u64;
|
||
dirent.d_off = 0;
|
||
dirent.d_reclen = 0;
|
||
dirent.d_type = sub_inode.metadata().unwrap().file_type.get_file_type_num() as u8;
|
||
// 根据posix的规定，dirent中的d_name是一个不定长的数组，因此需要unsafe来拷贝数据
|
||
unsafe {
|
||
let ptr = &mut dirent.d_name as *mut u8;
|
||
let buf: &mut [u8] =
|
||
::core::slice::from_raw_parts_mut::<'static, u8>(ptr, name_bytes.len());
|
||
buf.copy_from_slice(name_bytes);
|
||
}
|
||
|
||
// 计算dirent结构体的大小
|
||
return Ok((name_bytes.len() + ::core::mem::size_of::<Dirent>()
|
||
- ::core::mem::size_of_val(&dirent.d_name)) as u64);
|
||
}
|
||
|
||
pub fn inode(&self) -> Arc<dyn IndexNode> {
|
||
return self.inode.clone();
|
||
}
|
||
|
||
/// @brief 尝试克隆一个文件
|
||
///
|
||
/// @return Option<Box<File>> 克隆后的文件结构体。如果克隆失败，返回None
|
||
pub fn try_clone(&self) -> Option<Box<File>> {
|
||
let mut res: Box<File> = Box::new(Self {
|
||
inode: self.inode.clone(),
|
||
offset: self.offset.clone(),
|
||
mode: self.mode.clone(),
|
||
file_type: self.file_type.clone(),
|
||
readdir_subdirs_name: self.readdir_subdirs_name.clone(),
|
||
private_data: self.private_data.clone(),
|
||
});
|
||
// 调用inode的open方法，让inode知道有新的文件打开了这个inode
|
||
if self.inode.open(&mut res.private_data, &res.mode).is_err() {
|
||
return None;
|
||
}
|
||
|
||
return Some(res);
|
||
}
|
||
}
|
||
|
||
impl Drop for File {
|
||
fn drop(&mut self) {
|
||
let r: Result<(), SystemError> = self.inode.close(&mut self.private_data);
|
||
// 打印错误信息
|
||
if r.is_err() {
|
||
kerror!(
|
||
"pid: {} failed to close file: {:?}, errno={:?}",
|
||
current_pcb().pid,
|
||
self,
|
||
r.unwrap_err()
|
||
);
|
||
}
|
||
}
|
||
}
|
||
|
||
/// @brief pcb里面的文件描述符数组
|
||
#[derive(Debug)]
|
||
pub struct FileDescriptorVec {
|
||
/// 当前进程打开的文件描述符
|
||
pub fds: [Option<Box<File>>; FileDescriptorVec::PROCESS_MAX_FD],
|
||
}
|
||
|
||
impl FileDescriptorVec {
|
||
pub const PROCESS_MAX_FD: usize = 32;
|
||
|
||
pub fn new() -> Box<FileDescriptorVec> {
|
||
// 先声明一个未初始化的数组
|
||
let mut data: [MaybeUninit<Option<Box<File>>>; FileDescriptorVec::PROCESS_MAX_FD] =
|
||
unsafe { MaybeUninit::uninit().assume_init() };
|
||
|
||
// 逐个把每个元素初始化为None
|
||
for i in 0..FileDescriptorVec::PROCESS_MAX_FD {
|
||
data[i] = MaybeUninit::new(None);
|
||
}
|
||
// 由于一切都初始化完毕，因此将未初始化的类型强制转换为已经初始化的类型
|
||
let data: [Option<Box<File>>; FileDescriptorVec::PROCESS_MAX_FD] = unsafe {
|
||
core::mem::transmute::<_, [Option<Box<File>>; FileDescriptorVec::PROCESS_MAX_FD]>(data)
|
||
};
|
||
|
||
// 初始化文件描述符数组结构体
|
||
return Box::new(FileDescriptorVec { fds: data });
|
||
}
|
||
|
||
/// @brief 克隆一个文件描述符数组
|
||
///
|
||
/// @return Box<FileDescriptorVec> 克隆后的文件描述符数组
|
||
pub fn clone(&self) -> Box<FileDescriptorVec> {
|
||
let mut res: Box<FileDescriptorVec> = FileDescriptorVec::new();
|
||
for i in 0..FileDescriptorVec::PROCESS_MAX_FD {
|
||
if let Some(file) = &self.fds[i] {
|
||
res.fds[i] = file.try_clone();
|
||
}
|
||
}
|
||
return res;
|
||
}
|
||
|
||
/// @brief 从pcb的fds字段，获取文件描述符数组的可变引用
|
||
#[inline]
|
||
pub fn from_pcb(pcb: &'static process_control_block) -> Option<&'static mut FileDescriptorVec> {
|
||
return unsafe { (pcb.fds as usize as *mut FileDescriptorVec).as_mut() };
|
||
}
|
||
|
||
/// @brief 判断文件描述符序号是否合法
|
||
///
|
||
/// @return true 合法
|
||
///
|
||
/// @return false 不合法
|
||
#[inline]
|
||
pub fn validate_fd(fd: i32) -> bool {
|
||
if fd < 0 || fd as usize > FileDescriptorVec::PROCESS_MAX_FD {
|
||
return false;
|
||
} else {
|
||
return true;
|
||
}
|
||
}
|
||
}
|