1 use core::{ 2 ffi::{c_int, c_void}, 3 sync::atomic::compiler_fence, 4 }; 5 6 use system_error::SystemError; 7 8 use crate::{ 9 arch::ipc::signal::{SigCode, SigFlags, SigSet, Signal}, 10 filesystem::vfs::{ 11 file::{File, FileMode}, 12 FilePrivateData, 13 }, 14 kerror, kwarn, 15 mm::VirtAddr, 16 process::{Pid, ProcessManager}, 17 syscall::{user_access::UserBufferWriter, Syscall}, 18 }; 19 20 use super::{ 21 pipe::{LockedPipeInode, PipeFsPrivateData}, 22 signal_types::{ 23 SaHandlerType, SigInfo, SigType, Sigaction, SigactionType, UserSigaction, USER_SIG_DFL, 24 USER_SIG_ERR, USER_SIG_IGN, 25 }, 26 }; 27 28 impl Syscall { 29 /// # 创建带参数的匿名管道 30 /// 31 /// ## 参数 32 /// 33 /// - `fd`: 用于返回文件描述符的数组 34 /// - `flags`:设置管道的参数 35 pub fn pipe2(fd: *mut i32, flags: FileMode) -> Result<usize, SystemError> { 36 if flags.contains(FileMode::O_NONBLOCK) 37 || flags.contains(FileMode::O_CLOEXEC) 38 || flags.contains(FileMode::O_RDONLY) 39 { 40 let mut user_buffer = 41 UserBufferWriter::new(fd, core::mem::size_of::<[c_int; 2]>(), true)?; 42 let fd = user_buffer.buffer::<i32>(0)?; 43 let pipe_ptr = LockedPipeInode::new(); 44 let mut read_file = File::new(pipe_ptr.clone(), FileMode::O_RDONLY)?; 45 read_file.private_data = 46 FilePrivateData::Pipefs(PipeFsPrivateData::new(FileMode::O_RDONLY)); 47 let mut write_file = File::new(pipe_ptr.clone(), FileMode::O_WRONLY)?; 48 write_file.private_data = 49 FilePrivateData::Pipefs(PipeFsPrivateData::new(FileMode::O_WRONLY)); 50 if flags.contains(FileMode::O_CLOEXEC) { 51 read_file.set_close_on_exec(true); 52 write_file.set_close_on_exec(true); 53 } 54 let fd_table_ptr = ProcessManager::current_pcb().fd_table(); 55 let mut fd_table_guard = fd_table_ptr.write(); 56 let read_fd = fd_table_guard.alloc_fd(read_file, None)?; 57 let write_fd = fd_table_guard.alloc_fd(write_file, None)?; 58 59 drop(fd_table_guard); 60 61 fd[0] = read_fd; 62 fd[1] = write_fd; 63 Ok(0) 64 } else { 65 Err(SystemError::EINVAL) 66 } 67 } 68 69 pub fn kill(pid: Pid, sig: c_int) -> Result<usize, SystemError> { 70 let sig = Signal::from(sig); 71 if sig == Signal::INVALID { 72 // 传入的signal数值不合法 73 kwarn!("Not a valid signal number"); 74 return Err(SystemError::EINVAL); 75 } 76 77 // 初始化signal info 78 let mut info = SigInfo::new(sig, 0, SigCode::User, SigType::Kill(pid)); 79 80 compiler_fence(core::sync::atomic::Ordering::SeqCst); 81 82 let retval = sig 83 .send_signal_info(Some(&mut info), pid) 84 .map(|x| x as usize); 85 86 compiler_fence(core::sync::atomic::Ordering::SeqCst); 87 88 return retval; 89 } 90 91 /// 通用信号注册函数 92 /// 93 /// ## 参数 94 /// 95 /// - `sig` 信号的值 96 /// - `act` 用户空间传入的 Sigaction 指针 97 /// - `old_act` 用户空间传入的用来保存旧 Sigaction 的指针 98 /// - `from_user` 用来标识这个函数调用是否来自用户空间 99 /// 100 /// @return int 错误码 101 #[no_mangle] 102 pub fn sigaction( 103 sig: c_int, 104 new_act: usize, 105 old_act: usize, 106 from_user: bool, 107 ) -> Result<usize, SystemError> { 108 // 请注意：用户态传进来的user_sigaction结构体类型，请注意，这个结构体与内核实际的不一样 109 let act: *mut UserSigaction = new_act as *mut UserSigaction; 110 let old_act = old_act as *mut UserSigaction; 111 let mut new_ka: Sigaction = Default::default(); 112 let mut old_sigaction: Sigaction = Default::default(); 113 // 如果传入的，新的sigaction不为空 114 if !act.is_null() { 115 // 如果参数的范围不在用户空间，则返回错误 116 let r = UserBufferWriter::new(act, core::mem::size_of::<Sigaction>(), from_user); 117 if r.is_err() { 118 return Err(SystemError::EFAULT); 119 } 120 let mask: SigSet = unsafe { (*act).mask }; 121 let input_sighandler = unsafe { (*act).handler as u64 }; 122 match input_sighandler { 123 USER_SIG_DFL => { 124 new_ka = Sigaction::DEFAULT_SIGACTION.clone(); 125 *new_ka.flags_mut() = unsafe { (*act).flags }; 126 new_ka.set_restorer(None); 127 } 128 129 USER_SIG_IGN => { 130 new_ka = Sigaction::DEFAULT_SIGACTION_IGNORE.clone(); 131 *new_ka.flags_mut() = unsafe { (*act).flags }; 132 133 new_ka.set_restorer(None); 134 } 135 _ => { 136 // 从用户空间获得sigaction结构体 137 // TODO mask是default还是用户空间传入 138 new_ka = Sigaction::new( 139 SigactionType::SaHandler(SaHandlerType::SigCustomized(unsafe { 140 VirtAddr::new((*act).handler as usize) 141 })), 142 unsafe { (*act).flags }, 143 SigSet::default(), 144 unsafe { Some(VirtAddr::new((*act).restorer as usize)) }, 145 ); 146 } 147 } 148 149 // TODO 如果为空，赋默认值？ 150 // kdebug!("new_ka={:?}", new_ka); 151 // 如果用户手动给了sa_restorer，那么就置位SA_FLAG_RESTORER，否则报错。（用户必须手动指定restorer） 152 if new_ka.restorer().is_some() { 153 new_ka.flags_mut().insert(SigFlags::SA_RESTORER); 154 } else if new_ka.action().is_customized() { 155 kerror!( 156 "pid:{:?}: in sys_sigaction: User must manually sprcify a sa_restorer for signal {}.", 157 ProcessManager::current_pcb().pid(), 158 sig 159 ); 160 return Err(SystemError::EINVAL); 161 } 162 *new_ka.mask_mut() = mask; 163 } 164 165 let sig = Signal::from(sig as i32); 166 // 如果给出的信号值不合法 167 if sig == Signal::INVALID { 168 return Err(SystemError::EINVAL); 169 } 170 171 let retval = super::signal::do_sigaction( 172 sig, 173 if act.is_null() { 174 None 175 } else { 176 Some(&mut new_ka) 177 }, 178 if old_act.is_null() { 179 None 180 } else { 181 Some(&mut old_sigaction) 182 }, 183 ); 184 185 // 186 if (retval == Ok(())) && (!old_act.is_null()) { 187 let r = 188 UserBufferWriter::new(old_act, core::mem::size_of::<UserSigaction>(), from_user); 189 if r.is_err() { 190 return Err(SystemError::EFAULT); 191 } 192 193 let sigaction_handler: VirtAddr; 194 sigaction_handler = match old_sigaction.action() { 195 SigactionType::SaHandler(handler) => { 196 if let SaHandlerType::SigCustomized(hand) = handler { 197 hand 198 } else if handler.is_sig_ignore() { 199 VirtAddr::new(USER_SIG_IGN as usize) 200 } else if handler.is_sig_error() { 201 VirtAddr::new(USER_SIG_ERR as usize) 202 } else { 203 VirtAddr::new(USER_SIG_DFL as usize) 204 } 205 } 206 SigactionType::SaSigaction(_) => { 207 kerror!("unsupported type: SaSigaction"); 208 VirtAddr::new(USER_SIG_DFL as usize) 209 } 210 }; 211 212 unsafe { 213 (*old_act).handler = sigaction_handler.data() as *mut c_void; 214 (*old_act).flags = old_sigaction.flags(); 215 (*old_act).mask = old_sigaction.mask(); 216 if old_sigaction.restorer().is_some() { 217 (*old_act).restorer = old_sigaction.restorer().unwrap().data() as *mut c_void; 218 } 219 } 220 } 221 return retval.map(|_| 0); 222 } 223 } 224