mirror of
https://github.com/DragonOS-Community/DragonOS.git
synced 2025-06-08 18:26:48 +00:00
488718dc2e
feat: 实现poll系统调用实现并修复相关bug - 实现poll系统调用，增加对EPollEvent的处理逻辑 - 修复LockedPipeInode中epitems的锁管理问题 - 添加RestartBlock支持，处理系统调用重启逻辑 - 修复EventPoll中epoll_wait的超时处理逻辑 - 新增test_poll测试程序，验证poll功能 Signed-off-by: longjin <longjin@DragonOS.org>
711 lines
26 KiB
Rust
711 lines
26 KiB
Rust
use core::{fmt::Debug, sync::atomic::compiler_fence};
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use alloc::sync::Arc;
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use log::warn;
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use system_error::SystemError;
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use crate::{
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arch::ipc::signal::{SigCode, SigFlags, SigSet, Signal},
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ipc::signal_types::SigactionType,
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libs::spinlock::SpinLockGuard,
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mm::VirtAddr,
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process::{
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pid::PidType, Pid, ProcessControlBlock, ProcessFlags, ProcessManager, ProcessSignalInfo,
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},
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time::Instant,
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};
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use super::signal_types::{
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SaHandlerType, SigInfo, SigType, Sigaction, SignalStruct, SIG_KERNEL_STOP_MASK,
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};
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impl Signal {
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pub fn signal_pending_state(
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interruptible: bool,
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task_wake_kill: bool,
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pcb: &Arc<ProcessControlBlock>,
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) -> bool {
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if !interruptible && !task_wake_kill {
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return false;
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}
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if !pcb.has_pending_signal_fast() {
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return false;
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}
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return interruptible || Self::fatal_signal_pending(pcb);
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}
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/// 判断当前进程是否收到了SIGKILL信号
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pub fn fatal_signal_pending(pcb: &Arc<ProcessControlBlock>) -> bool {
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let guard = pcb.sig_info_irqsave();
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if guard
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.sig_pending()
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.signal()
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.contains(Signal::SIGKILL.into())
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{
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return true;
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}
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return false;
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}
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/// 向目标进程发送信号
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///
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/// ## 参数
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///
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/// - `sig` 要发送的信号
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/// - `info` 要发送的信息
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/// - `pid` 进程id（目前只支持pid>0)
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pub fn send_signal_info(
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&self,
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info: Option<&mut SigInfo>,
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pid: Pid,
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) -> Result<i32, SystemError> {
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// TODO:暂时不支持特殊的信号操作，待引入进程组后补充
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// 如果 pid 大于 0，那么会发送信号给 pid 指定的进程
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// 如果 pid 等于 0，那么会发送信号给与调用进程同组的每个进程，包括调用进程自身
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// 如果 pid 小于 -1，那么会向组 ID 等于该 pid 绝对值的进程组内所有下属进程发送信号。向一个进程组的所有进程发送信号在 shell 作业控制中有特殊有途
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// 如果 pid 等于 -1，那么信号的发送范围是：调用进程有权将信号发往的每个目标进程，除去 init（进程 ID 为 1）和调用进程自身。如果特权级进程发起这一调用，那么会发送信号给系统中的所有进程，上述两个进程除外。显而易见，有时也将这种信号发送方式称之为广播信号
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// 如果并无进程与指定的 pid 相匹配，那么 kill() 调用失败，同时将 errno 置为 ESRCH（“查无此进程”）
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if pid.lt(&Pid::from(0)) {
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warn!("Kill operation not support: pid={:?}", pid);
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return Err(SystemError::ENOSYS);
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}
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// 暂时不支持发送信号给进程组
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if pid.data() == 0 {
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return Err(SystemError::ENOSYS);
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}
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compiler_fence(core::sync::atomic::Ordering::SeqCst);
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// 检查sig是否符合要求，如果不符合要求，则退出。
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if !self.is_valid() {
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return Err(SystemError::EINVAL);
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}
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let mut retval = Err(SystemError::ESRCH);
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let pcb = ProcessManager::find(pid);
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if pcb.is_none() {
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warn!("No such process: pid={:?}", pid);
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return retval;
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}
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let pcb = pcb.unwrap();
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// println!("Target pcb = {:?}", pcb.as_ref().unwrap());
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compiler_fence(core::sync::atomic::Ordering::SeqCst);
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// 发送信号
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retval = self.send_signal(info, pcb.clone(), PidType::PID);
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compiler_fence(core::sync::atomic::Ordering::SeqCst);
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return retval;
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}
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/// @brief 判断是否需要强制发送信号，然后发送信号
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/// 进入函数后加锁
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///
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/// @return SystemError 错误码
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fn send_signal(
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&self,
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info: Option<&mut SigInfo>,
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pcb: Arc<ProcessControlBlock>,
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pt: PidType,
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) -> Result<i32, SystemError> {
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// 是否强制发送信号
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let mut force_send = false;
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// signal的信息为空
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if let Some(ref siginfo) = info {
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force_send = matches!(siginfo.sig_code(), SigCode::Kernel);
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} else {
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// todo: 判断signal是否来自于一个祖先进程的namespace，如果是，则强制发送信号
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//详见 https://code.dragonos.org.cn/xref/linux-6.1.9/kernel/signal.c?r=&mo=32170&fi=1220#1226
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}
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if !self.prepare_sianal(pcb.clone(), force_send) {
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return Ok(0);
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}
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// debug!("force send={}", force_send);
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let pcb_info = pcb.sig_info_irqsave();
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let pending = if matches!(pt, PidType::PID) {
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pcb_info.sig_shared_pending()
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} else {
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pcb_info.sig_pending()
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};
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compiler_fence(core::sync::atomic::Ordering::SeqCst);
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// 如果是kill或者目标pcb是内核线程，则无需获取sigqueue，直接发送信号即可
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if matches!(self, Signal::SIGKILL) || pcb.flags().contains(ProcessFlags::KTHREAD) {
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//避免死锁
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drop(pcb_info);
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self.complete_signal(pcb.clone(), pt);
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}
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// 如果不是实时信号的话，同一时刻信号队列里只会有一个待处理的信号，如果重复接收就不做处理
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else if !self.is_rt_signal() && pending.queue().find(*self).0.is_some() {
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return Ok(0);
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} else {
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// TODO signalfd_notify 完善 signalfd 机制
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// 如果是其他信号，则加入到sigqueue内，然后complete_signal
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let new_sig_info = match info {
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Some(siginfo) => {
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// 已经显式指定了siginfo，则直接使用它。
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*siginfo
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}
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None => {
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// 不需要显示指定siginfo，因此设置为默认值
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SigInfo::new(
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*self,
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0,
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SigCode::User,
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SigType::Kill(ProcessManager::current_pcb().pid()),
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)
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}
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};
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drop(pcb_info);
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pcb.sig_info_mut()
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.sig_pending_mut()
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.queue_mut()
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.q
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.push(new_sig_info);
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// if pt == PidType::PGID || pt == PidType::SID {}
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self.complete_signal(pcb.clone(), pt);
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}
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compiler_fence(core::sync::atomic::Ordering::SeqCst);
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return Ok(0);
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}
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/// @brief 将信号添加到目标进程的sig_pending。在引入进程组后，本函数还将负责把信号传递给整个进程组。
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///
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/// @param sig 信号
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/// @param pcb 目标pcb
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/// @param pt siginfo结构体中，pid字段代表的含义
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#[allow(clippy::if_same_then_else)]
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fn complete_signal(&self, pcb: Arc<ProcessControlBlock>, pt: PidType) {
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// debug!("complete_signal");
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compiler_fence(core::sync::atomic::Ordering::SeqCst);
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// ===== 寻找需要wakeup的目标进程 =====
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// 备注：由于当前没有进程组的概念，每个进程只有1个对应的线程，因此不需要通知进程组内的每个进程。
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// todo: 当引入进程组的概念后，需要完善这里，使得它能寻找一个目标进程来唤醒，接着执行信号处理的操作。
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// let _signal = pcb.sig_struct();
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let target_pcb: Option<Arc<ProcessControlBlock>>;
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// 判断目标进程是否想接收这个信号
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if self.wants_signal(pcb.clone()) {
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// todo: 将信号产生的消息通知到正在监听这个信号的进程（引入signalfd之后，在这里调用signalfd_notify)
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// 将这个信号加到目标进程的sig_pending中
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pcb.sig_info_mut()
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.sig_pending_mut()
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.signal_mut()
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.insert((*self).into());
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target_pcb = Some(pcb.clone());
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} else if pt == PidType::PID {
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/*
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* There is just one thread and it does not need to be woken.
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* It will dequeue unblocked signals before it runs again.
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*/
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return;
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} else {
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/*
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* Otherwise try to find a suitable thread.
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* 由于目前每个进程只有1个线程，因此当前情况可以返回。信号队列的dequeue操作不需要考虑同步阻塞的问题。
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*/
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return;
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}
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// TODO:引入进程组后，在这里挑选一个进程来唤醒，让它执行相应的操作。
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compiler_fence(core::sync::atomic::Ordering::SeqCst);
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// TODO: 到这里，信号已经被放置在共享的pending队列中，我们在这里把目标进程唤醒。
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if let Some(target_pcb) = target_pcb {
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let guard = target_pcb.sig_struct();
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signal_wake_up(target_pcb.clone(), guard, *self == Signal::SIGKILL);
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}
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}
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/// 本函数用于检测指定的进程是否想要接收SIG这个信号。
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///
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/// 当我们对于进程组中的所有进程都运行了这个检查之后，我们将可以找到组内愿意接收信号的进程。
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/// 这么做是为了防止我们把信号发送给了一个正在或已经退出的进程，或者是不响应该信号的进程。
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#[inline]
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fn wants_signal(&self, pcb: Arc<ProcessControlBlock>) -> bool {
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// 如果改进程屏蔽了这个signal，则不能接收
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if pcb
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.sig_info_irqsave()
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.sig_blocked()
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.contains((*self).into())
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{
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return false;
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}
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// 如果进程正在退出，则不能接收信号
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if pcb.flags().contains(ProcessFlags::EXITING) {
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return false;
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}
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if *self == Signal::SIGKILL {
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return true;
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}
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let state = pcb.sched_info().inner_lock_read_irqsave().state();
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if state.is_blocked() && (!state.is_blocked_interruptable()) {
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return false;
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}
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// todo: 检查目标进程是否正在一个cpu上执行，如果是，则返回true，否则继续检查下一项
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// 检查目标进程是否有信号正在等待处理，如果是，则返回false，否则返回true
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return pcb.sig_info_irqsave().sig_pending().signal().bits() == 0;
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}
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/// @brief 判断signal的处理是否可能使得整个进程组退出
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/// @return true 可能会导致退出（不一定）
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#[allow(dead_code)]
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#[inline]
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fn sig_fatal(&self, pcb: Arc<ProcessControlBlock>) -> bool {
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let action = pcb.sig_struct().handlers[*self as usize - 1].action();
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// 如果handler是空，采用默认函数，signal处理可能会导致进程退出。
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match action {
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SigactionType::SaHandler(handler) => handler.is_sig_default(),
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SigactionType::SaSigaction(sigaction) => sigaction.is_none(),
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}
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// todo: 参照linux的sig_fatal实现完整功能
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}
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/// 检查信号是否能被发送，并且而且要处理 SIGCONT 和 STOP 信号
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///
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/// ## 参数
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///
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/// - `pcb` 要发送信号的目标pcb
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///
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/// - `force` 是否强制发送(指走 fast path ， 不加入 sigpending按顺序处理，直接进入 complete_signal)
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///
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/// ## 返回值
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///
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/// - `true` 能够发送信号
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///
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/// - `false` 不能发送信号
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fn prepare_sianal(&self, pcb: Arc<ProcessControlBlock>, _force: bool) -> bool {
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let flush: SigSet;
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if !(self.into_sigset() & SIG_KERNEL_STOP_MASK).is_empty() {
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flush = Signal::SIGCONT.into_sigset();
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pcb.sig_info_mut()
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.sig_shared_pending_mut()
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.flush_by_mask(&flush);
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// TODO 对每个子线程 flush mask
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} else if *self == Signal::SIGCONT {
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flush = SIG_KERNEL_STOP_MASK;
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assert!(!flush.is_empty());
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pcb.sig_info_mut()
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.sig_shared_pending_mut()
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.flush_by_mask(&flush);
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let _r = ProcessManager::wakeup_stop(&pcb);
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// TODO 对每个子线程 flush mask
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// 这里需要补充一段逻辑，详见https://code.dragonos.org.cn/xref/linux-6.1.9/kernel/signal.c#952
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}
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// 一个被阻塞了的信号肯定是要被处理的
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if pcb
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.sig_info_irqsave()
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.sig_blocked()
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.contains(self.into_sigset())
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{
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return true;
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}
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return !pcb.sig_struct().handlers[*self as usize - 1].is_ignore();
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//TODO 仿照 linux 中的prepare signal完善逻辑，linux 中还会根据例如当前进程状态(Existing)进行判断，现在的信号能否发出就只是根据 ignored 来判断
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}
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}
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/// 因收到信号而唤醒进程
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///
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/// ## 参数
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///
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/// - `pcb` 要唤醒的进程pcb
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/// - `_guard` 信号结构体锁守卫，来保证信号结构体已上锁
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/// - `fatal` 表明这个信号是不是致命的(会导致进程退出)
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#[inline]
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fn signal_wake_up(pcb: Arc<ProcessControlBlock>, _guard: SpinLockGuard<SignalStruct>, fatal: bool) {
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// 如果是 fatal 的话就唤醒 stop 和 block 的进程来响应，因为唤醒后就会终止
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// 如果不是 fatal 的就只唤醒 stop 的进程来响应
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// debug!("signal_wake_up");
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// 如果目标进程已经在运行，则发起一个ipi，使得它陷入内核
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let state = pcb.sched_info().inner_lock_read_irqsave().state();
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pcb.flags().insert(ProcessFlags::HAS_PENDING_SIGNAL);
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let mut wakeup_ok = true;
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if state.is_blocked_interruptable() {
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ProcessManager::wakeup(&pcb).unwrap_or_else(|e| {
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wakeup_ok = false;
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warn!(
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"Current pid: {:?}, signal_wake_up target {:?} error: {:?}",
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ProcessManager::current_pcb().pid(),
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pcb.pid(),
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e
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);
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});
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} else if state.is_stopped() {
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ProcessManager::wakeup_stop(&pcb).unwrap_or_else(|e| {
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wakeup_ok = false;
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warn!(
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"Current pid: {:?}, signal_wake_up target {:?} error: {:?}",
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ProcessManager::current_pcb().pid(),
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pcb.pid(),
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e
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);
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});
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} else {
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wakeup_ok = false;
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}
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if wakeup_ok {
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ProcessManager::kick(&pcb);
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} else if fatal {
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let _r = ProcessManager::wakeup(&pcb).map(|_| {
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ProcessManager::kick(&pcb);
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});
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}
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}
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fn has_pending_signals(sigset: &SigSet, blocked: &SigSet) -> bool {
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sigset.bits() & (!blocked.bits()) != 0
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}
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impl ProcessControlBlock {
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/// 重新计算线程的flag中的TIF_SIGPENDING位
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/// 参考: https://code.dragonos.org.cn/xref/linux-6.1.9/kernel/signal.c?r=&mo=4806&fi=182#182
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pub fn recalc_sigpending(&self, siginfo_guard: Option<&ProcessSignalInfo>) {
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if !self.recalc_sigpending_tsk(siginfo_guard) {
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self.flags().remove(ProcessFlags::HAS_PENDING_SIGNAL);
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}
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}
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fn recalc_sigpending_tsk(&self, siginfo_guard: Option<&ProcessSignalInfo>) -> bool {
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let mut _siginfo_tmp_guard = None;
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let siginfo = if let Some(siginfo_guard) = siginfo_guard {
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siginfo_guard
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} else {
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_siginfo_tmp_guard = Some(self.sig_info_irqsave());
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_siginfo_tmp_guard.as_ref().unwrap()
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};
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return siginfo.do_recalc_sigpending_tsk(self);
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}
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}
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impl ProcessSignalInfo {
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fn do_recalc_sigpending_tsk(&self, pcb: &ProcessControlBlock) -> bool {
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if has_pending_signals(&self.sig_pending().signal(), self.sig_blocked())
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|| has_pending_signals(&self.sig_shared_pending().signal(), self.sig_blocked())
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{
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pcb.flags().insert(ProcessFlags::HAS_PENDING_SIGNAL);
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return true;
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}
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/*
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* We must never clear the flag in another thread, or in current
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* when it's possible the current syscall is returning -ERESTART*.
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* So we don't clear it here, and only callers who know they should do.
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*/
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return false;
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}
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}
|
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/// 参考 https://code.dragonos.org.cn/xref/linux-6.1.9/include/linux/sched/signal.h?fi=restore_saved_sigmask#547
|
||
pub fn restore_saved_sigmask() {
|
||
if ProcessManager::current_pcb()
|
||
.flags()
|
||
.test_and_clear(ProcessFlags::RESTORE_SIG_MASK)
|
||
{
|
||
let saved = *ProcessManager::current_pcb()
|
||
.sig_info_irqsave()
|
||
.saved_sigmask();
|
||
__set_current_blocked(&saved);
|
||
}
|
||
}
|
||
|
||
/// 刷新指定进程的sighand的sigaction，将满足条件的sigaction恢复为默认状态。
|
||
/// 除非某个信号被设置为忽略且 `force_default` 为 `false`，否则都不会将其恢复。
|
||
///
|
||
/// # 参数
|
||
///
|
||
/// - `pcb`: 要被刷新的pcb。
|
||
/// - `force_default`: 是否强制将sigaction恢复成默认状态。
|
||
pub fn flush_signal_handlers(pcb: Arc<ProcessControlBlock>, force_default: bool) {
|
||
compiler_fence(core::sync::atomic::Ordering::SeqCst);
|
||
// debug!("hand=0x{:018x}", hand as *const sighand_struct as usize);
|
||
let actions = &mut pcb.sig_struct_irqsave().handlers;
|
||
|
||
for sigaction in actions.iter_mut() {
|
||
if force_default || !sigaction.is_ignore() {
|
||
sigaction.set_action(SigactionType::SaHandler(SaHandlerType::Default));
|
||
}
|
||
// 清除flags中，除了DFL和IGN以外的所有标志
|
||
sigaction.set_restorer(None);
|
||
sigaction.mask_mut().remove(SigSet::all());
|
||
compiler_fence(core::sync::atomic::Ordering::SeqCst);
|
||
}
|
||
compiler_fence(core::sync::atomic::Ordering::SeqCst);
|
||
}
|
||
|
||
pub(super) fn do_sigaction(
|
||
sig: Signal,
|
||
act: Option<&mut Sigaction>,
|
||
old_act: Option<&mut Sigaction>,
|
||
) -> Result<(), SystemError> {
|
||
if sig == Signal::INVALID {
|
||
return Err(SystemError::EINVAL);
|
||
}
|
||
let pcb = ProcessManager::current_pcb();
|
||
// 指向当前信号的action的引用
|
||
let action: &mut Sigaction = &mut pcb.sig_struct().handlers[sig as usize - 1];
|
||
|
||
// 对比 MUSL 和 relibc ， 暂时不设置这个标志位
|
||
// if action.flags().contains(SigFlags::SA_FLAG_IMMUTABLE) {
|
||
// return Err(SystemError::EINVAL);
|
||
// }
|
||
|
||
// 保存原有的 sigaction
|
||
let old_act: Option<&mut Sigaction> = {
|
||
if let Some(oa) = old_act {
|
||
*(oa) = *action;
|
||
Some(oa)
|
||
} else {
|
||
None
|
||
}
|
||
};
|
||
// 清除所有的脏的sa_flags位（也就是清除那些未使用的）
|
||
let act = {
|
||
if let Some(ac) = act {
|
||
*ac.flags_mut() &= SigFlags::SA_ALL;
|
||
Some(ac)
|
||
} else {
|
||
None
|
||
}
|
||
};
|
||
|
||
if let Some(act) = old_act {
|
||
*act.flags_mut() &= SigFlags::SA_ALL;
|
||
}
|
||
|
||
if let Some(ac) = act {
|
||
// 将act.sa_mask的SIGKILL SIGSTOP的屏蔽清除
|
||
ac.mask_mut()
|
||
.remove(<Signal as Into<SigSet>>::into(Signal::SIGKILL) | Signal::SIGSTOP.into());
|
||
|
||
// 将新的sigaction拷贝到进程的action中
|
||
*action = *ac;
|
||
/*
|
||
* 根据POSIX 3.3.1.3规定：
|
||
* 1.不管一个信号是否被阻塞，只要将其设置SIG_IGN，如果当前已经存在了正在pending的信号，那么就把这个信号忽略。
|
||
*
|
||
* 2.不管一个信号是否被阻塞，只要将其设置SIG_DFL，如果当前已经存在了正在pending的信号，
|
||
并且对这个信号的默认处理方式是忽略它，那么就会把pending的信号忽略。
|
||
*/
|
||
if action.is_ignore() {
|
||
let mut mask: SigSet = SigSet::from_bits_truncate(0);
|
||
mask.insert(sig.into());
|
||
pcb.sig_info_mut().sig_pending_mut().flush_by_mask(&mask);
|
||
// todo: 当有了多个线程后，在这里进行操作，把每个线程的sigqueue都进行刷新
|
||
}
|
||
}
|
||
return Ok(());
|
||
}
|
||
|
||
/// https://code.dragonos.org.cn/xref/linux-6.6.21/include/uapi/asm-generic/signal-defs.h#72
|
||
/// 对应SIG_BLOCK，SIG_UNBLOCK，SIG_SETMASK
|
||
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
|
||
pub enum SigHow {
|
||
Block = 0,
|
||
Unblock = 1,
|
||
SetMask = 2,
|
||
}
|
||
|
||
impl TryFrom<i32> for SigHow {
|
||
type Error = SystemError;
|
||
fn try_from(value: i32) -> Result<Self, Self::Error> {
|
||
match value {
|
||
0 => Ok(SigHow::Block),
|
||
1 => Ok(SigHow::Unblock),
|
||
2 => Ok(SigHow::SetMask),
|
||
_ => Err(SystemError::EINVAL),
|
||
}
|
||
}
|
||
}
|
||
|
||
fn __set_task_blocked(pcb: &Arc<ProcessControlBlock>, new_set: &SigSet) {
|
||
//todo 还有一个对线程组是否为空的判断，进程组、线程组实现之后，需要更改这里。
|
||
if pcb.has_pending_signal() {
|
||
let mut newblocked = *new_set;
|
||
let guard = pcb.sig_info_irqsave();
|
||
newblocked.remove(*guard.sig_blocked());
|
||
drop(guard);
|
||
|
||
// 从主线程开始去遍历
|
||
if let Some(group_leader) = pcb.threads_read_irqsave().group_leader() {
|
||
retarget_shared_pending(group_leader, newblocked);
|
||
}
|
||
}
|
||
*pcb.sig_info_mut().sig_block_mut() = *new_set;
|
||
pcb.recalc_sigpending(None);
|
||
}
|
||
|
||
fn __set_current_blocked(new_set: &SigSet) {
|
||
let pcb = ProcessManager::current_pcb();
|
||
/*
|
||
如果当前pcb的sig_blocked和新的相等，那么就不用改变它。
|
||
请注意，一个进程的sig_blocked字段不能被其他进程修改！
|
||
*/
|
||
if pcb.sig_info_irqsave().sig_blocked().eq(new_set) {
|
||
return;
|
||
}
|
||
let guard: SpinLockGuard<'_, SignalStruct> = pcb.sig_struct_irqsave();
|
||
|
||
__set_task_blocked(&pcb, new_set);
|
||
|
||
drop(guard);
|
||
}
|
||
|
||
fn retarget_shared_pending(pcb: Arc<ProcessControlBlock>, which: SigSet) {
|
||
let retarget = pcb.sig_info_irqsave().sig_shared_pending().signal();
|
||
retarget.intersects(which);
|
||
if retarget.is_empty() {
|
||
return;
|
||
}
|
||
|
||
// 对于线程组中的每一个线程都要执行的函数
|
||
let thread_handling_function = |pcb: Arc<ProcessControlBlock>, retarget: &SigSet| {
|
||
if retarget.is_empty() {
|
||
return;
|
||
}
|
||
|
||
if pcb.flags().contains(ProcessFlags::EXITING) {
|
||
return;
|
||
}
|
||
|
||
let blocked = pcb.sig_info_irqsave().sig_shared_pending().signal();
|
||
if retarget.difference(blocked).is_empty() {
|
||
return;
|
||
}
|
||
|
||
retarget.intersects(blocked);
|
||
if !pcb.has_pending_signal() {
|
||
let guard = pcb.sig_struct_irqsave();
|
||
signal_wake_up(pcb.clone(), guard, false);
|
||
}
|
||
// 之前的对retarget的判断移动到最前面，因为对于当前线程的线程的处理已经结束，对于后面的线程在一开始判断retarget为空即可结束处理
|
||
|
||
// debug!("handle done");
|
||
};
|
||
|
||
// 暴力遍历每一个线程，找到相同的tgid
|
||
let tgid = pcb.tgid();
|
||
for &pid in pcb.children_read_irqsave().iter() {
|
||
if let Some(child) = ProcessManager::find(pid) {
|
||
if child.tgid() == tgid {
|
||
thread_handling_function(child, &retarget);
|
||
}
|
||
}
|
||
}
|
||
// debug!("retarget_shared_pending done!");
|
||
}
|
||
|
||
/// 设置当前进程的屏蔽信号 (sig_block)
|
||
///
|
||
/// ## 参数
|
||
///
|
||
/// - `new_set` 新的屏蔽信号bitmap的值
|
||
pub fn set_current_blocked(new_set: &mut SigSet) {
|
||
let to_remove: SigSet =
|
||
<Signal as Into<SigSet>>::into(Signal::SIGKILL) | Signal::SIGSTOP.into();
|
||
new_set.remove(to_remove);
|
||
__set_current_blocked(new_set);
|
||
}
|
||
|
||
/// 参考 https://code.dragonos.org.cn/xref/linux-6.6.21/kernel/signal.c?fi=set_user_sigmask#set_user_sigmask
|
||
/// 功能与set_current_blocked相同，多一步保存当前的sig_blocked到saved_sigmask
|
||
/// 由于这之中设置了saved_sigmask，因此从系统调用返回之前需要恢复saved_sigmask
|
||
pub fn set_user_sigmask(new_set: &mut SigSet) {
|
||
let pcb = ProcessManager::current_pcb();
|
||
let mut guard = pcb.sig_info_mut();
|
||
let oset = *guard.sig_blocked();
|
||
|
||
let flags = pcb.flags();
|
||
flags.set(ProcessFlags::RESTORE_SIG_MASK, true);
|
||
|
||
let saved_sigmask = guard.saved_sigmask_mut();
|
||
*saved_sigmask = oset;
|
||
drop(guard);
|
||
|
||
set_current_blocked(new_set);
|
||
}
|
||
|
||
/// 设置当前进程的屏蔽信号 (sig_block)
|
||
///
|
||
/// ## 参数
|
||
///
|
||
/// - `how` 设置方式
|
||
/// - `new_set` 新的屏蔽信号bitmap的值
|
||
pub fn set_sigprocmask(how: SigHow, set: SigSet) -> Result<SigSet, SystemError> {
|
||
let pcb: Arc<ProcessControlBlock> = ProcessManager::current_pcb();
|
||
let guard = pcb.sig_info_irqsave();
|
||
let oset = *guard.sig_blocked();
|
||
|
||
let mut res_set = oset;
|
||
drop(guard);
|
||
|
||
match how {
|
||
SigHow::Block => {
|
||
// debug!("SIG_BLOCK\tGoing to insert is: {}", set.bits());
|
||
res_set.insert(set);
|
||
}
|
||
SigHow::Unblock => {
|
||
res_set.remove(set);
|
||
}
|
||
SigHow::SetMask => {
|
||
// debug!("SIG_SETMASK\tGoing to set is: {}", set.bits());
|
||
res_set = set;
|
||
}
|
||
}
|
||
|
||
__set_current_blocked(&res_set);
|
||
Ok(oset)
|
||
}
|
||
|
||
#[derive(Debug)]
|
||
pub struct RestartBlock {
|
||
pub data: RestartBlockData,
|
||
pub restart_fn: &'static dyn RestartFn,
|
||
}
|
||
|
||
impl RestartBlock {
|
||
pub fn new(restart_fn: &'static dyn RestartFn, data: RestartBlockData) -> Self {
|
||
Self { data, restart_fn }
|
||
}
|
||
}
|
||
|
||
pub trait RestartFn: Debug + Sync + Send + 'static {
|
||
fn call(&self, data: &mut RestartBlockData) -> Result<usize, SystemError>;
|
||
}
|
||
|
||
#[derive(Debug, Clone)]
|
||
pub enum RestartBlockData {
|
||
Poll(PollRestartBlockData),
|
||
// todo: nanosleep
|
||
Nanosleep(),
|
||
// todo: futex_wait
|
||
FutexWait(),
|
||
}
|
||
|
||
impl RestartBlockData {
|
||
pub fn new_poll(pollfd_ptr: VirtAddr, nfds: u32, timeout_instant: Option<Instant>) -> Self {
|
||
Self::Poll(PollRestartBlockData {
|
||
pollfd_ptr,
|
||
nfds,
|
||
timeout_instant,
|
||
})
|
||
}
|
||
}
|
||
|
||
#[derive(Debug, Clone)]
|
||
pub struct PollRestartBlockData {
|
||
pub pollfd_ptr: VirtAddr,
|
||
pub nfds: u32,
|
||
pub timeout_instant: Option<Instant>,
|
||
}
|