use std::ffi::OsStr;
use std::os::windows::ffi::OsStrExt;
use std::path::{Component, Path, PathBuf, Prefix};
use windows_sys::Win32::Foundation::{
CloseHandle, GetLastError, ERROR_ACCESS_DENIED, ERROR_MORE_DATA, ERROR_SHARING_VIOLATION,
ERROR_SUCCESS, INVALID_HANDLE_VALUE,
};
use windows_sys::Win32::Storage::FileSystem::{
CreateFileW, GetFileAttributesW, GetLongPathNameW, RemoveDirectoryW, SetFileAttributesW,
FILE_ATTRIBUTE_READONLY, FILE_FLAG_BACKUP_SEMANTICS, FILE_SHARE_DELETE, FILE_SHARE_READ,
FILE_SHARE_WRITE, INVALID_FILE_ATTRIBUTES, OPEN_EXISTING,
};
use windows_sys::Win32::System::Diagnostics::Debug::{
FormatMessageW, FORMAT_MESSAGE_FROM_SYSTEM, FORMAT_MESSAGE_IGNORE_INSERTS,
};
use windows_sys::Win32::System::RestartManager::{
RmEndSession, RmForceShutdown, RmGetList, RmRegisterResources, RmShutdown, RmStartSession,
CCH_RM_SESSION_KEY, RM_PROCESS_INFO,
};
use windows_sys::Win32::System::Threading::{
GetCurrentProcessId, OpenProcess, QueryFullProcessImageNameW, TerminateProcess,
WaitForSingleObject, PROCESS_QUERY_LIMITED_INFORMATION, PROCESS_TERMINATE,
};
const DELETE_ACCESS: u32 = 0x0001_0000;
const RM_CRITICAL: u32 = 1000;
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct Locker {
pub pid: u32,
pub app_name: String,
pub image: Option<String>,
pub app_type: u32,
}
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct Inspection {
pub path: PathBuf,
pub lockers: Vec<Locker>,
pub sharing_violation: bool,
pub list_denied: bool,
}
pub fn inspect(path: &Path) -> Result<Inspection, String> {
let path = normalize_existing(path)?;
let (lockers, list_denied) = query_lockers(&path)?;
let sharing_violation = is_sharing_violation(&path);
Ok(Inspection {
path,
lockers,
sharing_violation,
list_denied,
})
}
pub fn release(path: &Path, force: bool) -> Result<Vec<Locker>, String> {
let inspection = inspect(path)?;
if inspection.lockers.is_empty() {
return Ok(Vec::new());
}
if let Some(reason) = critical_block(&inspection.lockers) {
return Err(reason);
}
let mut shutdown_error = match shutdown(&inspection.path, force) {
Ok(()) => None,
Err(error) => Some(error),
};
if !force && still_locked(path)? {
shutdown_error = match shutdown(path, true) {
Ok(()) => None,
Err(error) => Some(error),
};
}
for _ in 0..3 {
if !still_locked(path)? {
return Ok(inspection.lockers);
}
let current = inspect(path)?;
let targets = if current.lockers.is_empty() {
inspection.lockers.clone()
} else {
current.lockers
};
if let Some(reason) = critical_block(&targets) {
return Err(reason);
}
for locker in &targets {
end_process(locker.pid)?;
}
}
if still_locked(path)? {
if let Some(error) = shutdown_error {
return Err(error);
}
return Err(format!("{} 仍被占用", path.display()));
}
Ok(inspection.lockers)
}
pub fn delete_path(path: &Path, recursive: bool) -> Result<PathBuf, String> {
if let Some(reason) = block_reason(path) {
return Err(reason.to_string());
}
let path = normalize_existing(path)?;
if let Some(reason) = block_reason(&path) {
return Err(reason.to_string());
}
let metadata = std::fs::symlink_metadata(&path)
.map_err(|err| format!("无法读取 {}: {err}", path.display()))?;
if metadata.file_type().is_symlink() || is_reparse_point(&path) {
remove_link(&path)?;
return Ok(path);
}
if metadata.is_dir() {
remove_directory(&path, recursive)?;
return Ok(path);
}
clear_readonly(&path)?;
std::fs::remove_file(&path).map_err(|err| format!("删除 {} 失败: {err}", path.display()))?;
Ok(path)
}
pub fn block_reason(path: &Path) -> Option<&'static str> {
if path.as_os_str().is_empty() || is_drive_only(path) {
return Some("不能删除磁盘根目录");
}
let canon = path.canonicalize().unwrap_or_else(|_| path.to_path_buf());
if is_filesystem_root(&canon) || is_unc_share_root(&canon) {
return Some("不能删除磁盘根目录");
}
for known in protected_dirs() {
if same_path(&canon, &known) {
return Some("不能删除系统目录或用户主目录本身");
}
}
None
}
pub fn is_critical(locker: &Locker) -> bool {
if locker.pid <= 4 || locker.app_type == RM_CRITICAL {
return true;
}
const NAMES: &[&str] = &[
"smss.exe",
"csrss.exe",
"wininit.exe",
"winlogon.exe",
"services.exe",
"lsass.exe",
"dwm.exe",
"fontdrvhost.exe",
];
let mut names = Vec::new();
if let Some(image) = &locker.image {
if let Some(file_name) = Path::new(image).file_name() {
names.push(file_name.to_string_lossy().to_ascii_lowercase());
}
}
if !locker.app_name.is_empty() {
names.push(locker.app_name.to_ascii_lowercase());
}
names.iter().any(|name| NAMES.contains(&name.as_str()))
}
pub fn critical_block(lockers: &[Locker]) -> Option<String> {
let critical: Vec<_> = lockers
.iter()
.filter(|locker| is_critical(locker))
.collect();
if critical.is_empty() {
return None;
}
let listed = critical
.iter()
.map(|locker| format!("pid {} {}", locker.pid, display_name(locker)))
.collect::<Vec<_>>()
.join("，");
Some(format!("占用者包含关键系统进程，已拒绝解除占用: {listed}"))
}
pub fn display_name(locker: &Locker) -> String {
if !locker.app_name.is_empty() {
return locker.app_name.clone();
}
locker
.image
.as_deref()
.and_then(|image| {
Path::new(image)
.file_name()
.map(|name| name.to_string_lossy().into_owned())
})
.unwrap_or_else(|| "未知程序".to_string())
}
fn normalize_existing(path: &Path) -> Result<PathBuf, String> {
if path.as_os_str().is_empty() {
return Err("路径是空的".to_string());
}
let absolute = std::path::absolute(path)
.map_err(|err| format!("无法解析路径 {}: {err}", path.display()))?;
if !absolute.exists() {
return Err(format!("路径不存在: {}", absolute.display()));
}
Ok(long_path(&absolute))
}
fn query_lockers(path: &Path) -> Result<(Vec<Locker>, bool), String> {
let session = RestartSession::start()?;
match session.register(path) {
Ok(()) => {}
Err(ListError::Denied) => return Ok((Vec::new(), true)),
Err(ListError::Other(message)) => return Err(message),
}
match session.list() {
Ok(lockers) => Ok((lockers, false)),
Err(ListError::Denied) => Ok((Vec::new(), true)),
Err(ListError::Other(message)) => Err(message),
}
}
fn still_locked(path: &Path) -> Result<bool, String> {
match inspect(path) {
Ok(inspection) => Ok(inspection.sharing_violation || !inspection.lockers.is_empty()),
Err(error) if error.contains("路径不存在") => Ok(false),
Err(error) => Err(error),
}
}
fn end_process(pid: u32) -> Result<(), String> {
if pid <= 4 || pid == unsafe { GetCurrentProcessId() } {
return Err(format!("拒绝结束 pid {pid}"));
}
let access = PROCESS_TERMINATE | 0x0010_0000;
let handle = unsafe { OpenProcess(access, 0, pid) };
if handle.is_null() {
let code = unsafe { GetLastError() };
if code == 87 {
return Ok(());
}
return Err(format!("无法结束 pid {pid}: {}", win_message(code)));
}
let ended = unsafe { TerminateProcess(handle, 1) };
if ended == 0 {
let code = unsafe { GetLastError() };
unsafe { CloseHandle(handle) };
if code == 87 {
return Ok(());
}
return Err(format!("无法结束 pid {pid}: {}", win_message(code)));
}
unsafe {
WaitForSingleObject(handle, 3000);
CloseHandle(handle);
}
Ok(())
}
fn shutdown(path: &Path, force: bool) -> Result<(), String> {
let session = RestartSession::start()?;
session.register(path).map_err(|error| match error {
ListError::Denied => "没有权限解除占用".to_string(),
ListError::Other(message) => message,
})?;
let flags = if force { RmForceShutdown as u32 } else { 0 };
let code = unsafe { RmShutdown(session.0, flags, None) };
if code != ERROR_SUCCESS {
return Err(format!("解除占用失败: {}", win_message(code)));
}
Ok(())
}
enum ListError {
Denied,
Other(String),
}
struct RestartSession(u32);
impl RestartSession {
fn start() -> Result<Self, String> {
let mut handle = 0u32;
let mut key = [0u16; CCH_RM_SESSION_KEY as usize + 1];
let code = unsafe { RmStartSession(&mut handle, 0, key.as_mut_ptr()) };
if code != ERROR_SUCCESS {
return Err(format!("无法开始检查文件占用: {}", win_message(code)));
}
Ok(Self(handle))
}
fn register(&self, path: &Path) -> Result<(), ListError> {
let wide = wide_path(path);
let name = wide.as_ptr();
let code = unsafe {
RmRegisterResources(self.0, 1, &name, 0, std::ptr::null(), 0, std::ptr::null())
};
if code == ERROR_ACCESS_DENIED {
return Err(ListError::Denied);
}
if code != ERROR_SUCCESS {
return Err(ListError::Other(format!(
"无法登记 {}: {}",
path.display(),
win_message(code)
)));
}
Ok(())
}
fn list(&self) -> Result<Vec<Locker>, ListError> {
let mut needed = 0u32;
let mut count = 0u32;
let mut reasons = 0u32;
let code = unsafe {
RmGetList(
self.0,
&mut needed,
&mut count,
std::ptr::null_mut(),
&mut reasons,
)
};
if code == ERROR_SUCCESS && needed == 0 {
return Ok(Vec::new());
}
if code == ERROR_ACCESS_DENIED {
return Err(ListError::Denied);
}
if code != ERROR_MORE_DATA && !(code == ERROR_SUCCESS && needed > 0) {
return Err(ListError::Other(format!(
"无法列出占用进程: {}",
win_message(code)
)));
}
if needed == 0 {
return Ok(Vec::new());
}
if needed > 4096 {
return Err(ListError::Other("占用进程过多，已停止处理".to_string()));
}
let mut infos = Vec::with_capacity(needed as usize);
for _ in 0..needed {
infos.push(unsafe { std::mem::zeroed::<RM_PROCESS_INFO>() });
}
count = needed;
let code = unsafe {
RmGetList(
self.0,
&mut needed,
&mut count,
infos.as_mut_ptr(),
&mut reasons,
)
};
if code == ERROR_ACCESS_DENIED {
return Err(ListError::Denied);
}
if code != ERROR_SUCCESS {
return Err(ListError::Other(format!(
"无法列出占用进程: {}",
win_message(code)
)));
}
let mut lockers = Vec::new();
for info in infos.into_iter().take(count as usize) {
let pid = info.Process.dwProcessId;
if lockers.iter().any(|locker: &Locker| locker.pid == pid) {
continue;
}
lockers.push(Locker {
pid,
app_name: wide_to_string(&info.strAppName),
image: process_image(pid),
app_type: info.ApplicationType as u32,
});
}
lockers.sort_by_key(|locker| locker.pid);
Ok(lockers)
}
}
impl Drop for RestartSession {
fn drop(&mut self) {
unsafe {
RmEndSession(self.0);
}
}
}
fn process_image(pid: u32) -> Option<String> {
let handle = unsafe { OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION, 0, pid) };
if handle.is_null() {
return None;
}
let mut buffer = [0u16; 32768];
let mut size = buffer.len() as u32;
let ok = unsafe { QueryFullProcessImageNameW(handle, 0, buffer.as_mut_ptr(), &mut size) };
unsafe {
CloseHandle(handle);
}
if ok == 0 || size == 0 {
return None;
}
Some(String::from_utf16_lossy(&buffer[..size as usize]))
}
fn is_sharing_violation(path: &Path) -> bool {
let wide = wide_path(path);
let handle = unsafe {
CreateFileW(
wide.as_ptr(),
DELETE_ACCESS,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
std::ptr::null(),
OPEN_EXISTING,
FILE_FLAG_BACKUP_SEMANTICS,
std::ptr::null_mut(),
)
};
if handle == INVALID_HANDLE_VALUE {
return unsafe { GetLastError() } == ERROR_SHARING_VIOLATION;
}
unsafe {
CloseHandle(handle);
}
false
}
fn remove_directory(path: &Path, recursive: bool) -> Result<(), String> {
if !recursive {
let mut entries = std::fs::read_dir(path)
.map_err(|err| format!("无法读取目录 {}: {err}", path.display()))?;
if entries.next().is_some() {
return Err(format!(
"{} 是非空目录，删除请加 --recursive",
path.display()
));
}
std::fs::remove_dir(path)
.map_err(|err| format!("删除目录 {} 失败: {err}", path.display()))?;
return Ok(());
}
std::fs::remove_dir_all(path)
.map_err(|err| format!("删除目录 {} 失败: {err}", path.display()))?;
Ok(())
}
fn remove_link(path: &Path) -> Result<(), String> {
let metadata = std::fs::symlink_metadata(path)
.map_err(|err| format!("无法读取 {}: {err}", path.display()))?;
if metadata.file_type().is_symlink() && !metadata.is_dir() {
std::fs::remove_file(path).map_err(|err| format!("删除 {} 失败: {err}", path.display()))?;
return Ok(());
}
let wide = wide_path(path);
let ok = unsafe { RemoveDirectoryW(wide.as_ptr()) };
if ok == 0 {
return Err(format!(
"删除链接 {} 失败: {}",
path.display(),
win_message(unsafe { GetLastError() })
));
}
Ok(())
}
fn is_reparse_point(path: &Path) -> bool {
let wide = wide_path(path);
let attributes = unsafe { GetFileAttributesW(wide.as_ptr()) };
attributes != INVALID_FILE_ATTRIBUTES && attributes & 0x400 != 0
}
fn clear_readonly(path: &Path) -> Result<(), String> {
let wide = wide_path(path);
let attributes = unsafe { GetFileAttributesW(wide.as_ptr()) };
if attributes == INVALID_FILE_ATTRIBUTES || attributes & FILE_ATTRIBUTE_READONLY == 0 {
return Ok(());
}
let ok = unsafe { SetFileAttributesW(wide.as_ptr(), attributes & !FILE_ATTRIBUTE_READONLY) };
if ok == 0 {
return Err(format!(
"无法去掉 {} 的只读属性: {}",
path.display(),
win_message(unsafe { GetLastError() })
));
}
Ok(())
}
fn protected_dirs() -> Vec<PathBuf> {
let mut dirs = Vec::new();
if let Some(windows) = std::env::var_os("SystemRoot") {
let windows = PathBuf::from(&windows);
dirs.push(windows.join("System32"));
dirs.push(windows.join("SysWOW64"));
dirs.push(windows);
}
if let Some(drive) = std::env::var_os("SystemDrive") {
dirs.push(PathBuf::from(drive).join("Users"));
}
for name in [
"USERPROFILE",
"ProgramFiles",
"ProgramFiles(x86)",
"ProgramData",
] {
if let Some(value) = std::env::var_os(name) {
dirs.push(PathBuf::from(value));
}
}
dirs
}
fn same_path(left: &Path, right: &Path) -> bool {
match (left.canonicalize(), right.canonicalize()) {
(Ok(left), Ok(right)) => left == right,
_ => false,
}
}
fn is_drive_only(path: &Path) -> bool {
let text = path.to_string_lossy();
let trimmed = text.trim_end_matches(['\\', '/']);
trimmed.len() == 2 && trimmed.as_bytes().get(1) == Some(&b':')
}
fn is_filesystem_root(path: &Path) -> bool {
let mut saw_root = false;
for component in path.components() {
match component {
Component::RootDir | Component::Prefix(_) => saw_root = true,
Component::Normal(_) | Component::CurDir | Component::ParentDir => return false,
}
}
saw_root
}
fn is_unc_share_root(path: &Path) -> bool {
let mut components = path.components();
match components.next() {
Some(Component::Prefix(prefix)) if matches!(prefix.kind(), Prefix::UNC(..)) => {
components.all(|component| !matches!(component, Component::Normal(_)))
}
_ => false,
}
}
fn long_path(path: &Path) -> PathBuf {
let wide = wide_path(path);
let mut buffer = vec![0u16; 32768];
let length =
unsafe { GetLongPathNameW(wide.as_ptr(), buffer.as_mut_ptr(), buffer.len() as u32) };
if length == 0 || length as usize >= buffer.len() {
return path.to_path_buf();
}
PathBuf::from(String::from_utf16_lossy(&buffer[..length as usize]))
}
fn wide_path(path: &Path) -> Vec<u16> {
OsStr::new(path)
.encode_wide()
.chain(std::iter::once(0))
.collect()
}
fn wide_to_string(buffer: &[u16]) -> String {
let end = buffer
.iter()
.position(|unit| *unit == 0)
.unwrap_or(buffer.len());
String::from_utf16_lossy(&buffer[..end]).trim().to_string()
}
fn win_message(code: u32) -> String {
let mut buffer = [0u16; 512];
let length = unsafe {
FormatMessageW(
FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
std::ptr::null(),
code,
0,
buffer.as_mut_ptr(),
buffer.len() as u32,
std::ptr::null(),
)
};
if length == 0 {
return format!("Windows 错误 {code}");
}
let message = String::from_utf16_lossy(&buffer[..length as usize]);
let message = message.trim();
if message.is_empty() {
format!("Windows 错误 {code}")
} else {
format!("{message}（{code}）")
}
}
#[cfg(test)]
mod tests {
use super::*;
use std::fs;
#[test]
fn blocks_drive_root_and_windows_dir() {
assert_eq!(block_reason(Path::new(r"C:\")), Some("不能删除磁盘根目录"));
assert_eq!(block_reason(Path::new("C:")), Some("不能删除磁盘根目录"));
let windows = std::env::var("SystemRoot").unwrap();
assert!(block_reason(Path::new(&windows)).is_some());
let profile = std::env::var("USERPROFILE").unwrap();
assert!(block_reason(Path::new(&profile)).is_some());
}
#[test]
fn allows_a_normal_temp_file() {
let path = std::env::temp_dir().join("ffrm-allow-check.txt");
fs::write(&path, b"ok").unwrap();
assert_eq!(block_reason(&path), None);
let _ = fs::remove_file(&path);
}
#[test]
fn deletes_readonly_file_and_empty_dir() {
let file = std::env::temp_dir().join("ffrm-readonly-delete.txt");
fs::write(&file, b"gone").unwrap();
let wide = wide_path(&file);
unsafe {
let attributes = GetFileAttributesW(wide.as_ptr());
SetFileAttributesW(wide.as_ptr(), attributes | FILE_ATTRIBUTE_READONLY);
}
delete_path(&file, false).unwrap();
assert!(!file.exists());
let dir = std::env::temp_dir().join("ffrm-empty-dir");
fs::create_dir_all(&dir).unwrap();
delete_path(&dir, false).unwrap();
assert!(!dir.exists());
}
#[test]
fn refuses_nonempty_dir_without_recursive_and_removes_with_it() {
let dir = std::env::temp_dir().join("ffrm-nested-dir");
let child = dir.join("child.txt");
fs::create_dir_all(&dir).unwrap();
fs::write(&child, b"x").unwrap();
assert!(delete_path(&dir, false).is_err());
assert!(child.exists());
delete_path(&dir, true).unwrap();
assert!(!dir.exists());
}
#[test]
fn inspects_unlocked_temp_file() {
let file = std::env::temp_dir().join("ffrm-inspect.txt");
fs::write(&file, b"free").unwrap();
let inspection = inspect(&file).unwrap();
assert!(inspection.lockers.is_empty());
assert!(!inspection.sharing_violation);
fs::remove_file(file).unwrap();
}
#[test]
fn detects_critical_processes() {
let system = Locker {
pid: 4,
app_name: "System".to_string(),
image: None,
app_type: RM_CRITICAL,
};
assert!(is_critical(&system));
let notepad = Locker {
pid: 1200,
app_name: "记事本".to_string(),
image: Some(r"C:\Windows\System32\notepad.exe".to_string()),
app_type: 1,
};
assert!(!is_critical(¬epad));
let lsass = Locker {
pid: 800,
app_name: "Local Security Authority Process".to_string(),
image: Some(r"C:\Windows\System32\lsass.exe".to_string()),
app_type: 3,
};
assert!(is_critical(&lsass));
}
}