library/std/src/sys/windows/mod.rs

   1 #![allow(missing_docs, nonstandard_style)]
   2
   3 use crate::ffi::{OsStr, OsString};
   4 use crate::io::ErrorKind;
   5 use crate::os::windows::ffi::{OsStrExt, OsStringExt};
   6 use crate::path::PathBuf;
   7 use crate::time::Duration;
   8
   9 pub use self::rand::hashmap_random_keys;
  10 pub use libc::strlen;
  11
  12 #[macro_use]
  13 pub mod compat;
  14
  15 pub mod alloc;
  16 pub mod args;
  17 pub mod c;
  18 pub mod cmath;
  19 pub mod condvar;
  20 pub mod env;
  21 pub mod ext;
  22 pub mod fs;
  23 pub mod handle;
  24 pub mod io;
  25 pub mod memchr;
  26 pub mod mutex;
  27 pub mod net;
  28 pub mod os;
  29 pub mod os_str;
  30 pub mod path;
  31 pub mod pipe;
  32 pub mod process;
  33 pub mod rand;
  34 pub mod rwlock;
  35 pub mod thread;
  36 pub mod thread_local_dtor;
  37 pub mod thread_local_key;
  38 pub mod thread_parker;
  39 pub mod time;
  40 cfg_if::cfg_if! {
  41     if #[cfg(not(target_vendor = "uwp"))] {
  42         pub mod stdio;
  43         pub mod stack_overflow;
  44     } else {
  45         pub mod stdio_uwp;
  46         pub mod stack_overflow_uwp;
  47         pub use self::stdio_uwp as stdio;
  48         pub use self::stack_overflow_uwp as stack_overflow;
  49     }
  50 }
  51
  52 // SAFETY: must be called only once during runtime initialization.
  53 // NOTE: this is not guaranteed to run, for example when Rust code is called externally.
  54 pub unsafe fn init(_argc: isize, _argv: *const *const u8) {
  55     stack_overflow::init();
  56 }
  57
  58 // SAFETY: must be called only once during runtime cleanup.
  59 // NOTE: this is not guaranteed to run, for example when the program aborts.
  60 pub unsafe fn cleanup() {
  61     net::cleanup();
  62 }
  63
  64 pub fn decode_error_kind(errno: i32) -> ErrorKind {
  65     match errno as c::DWORD {
  66         c::ERROR_ACCESS_DENIED => return ErrorKind::PermissionDenied,
  67         c::ERROR_ALREADY_EXISTS => return ErrorKind::AlreadyExists,
  68         c::ERROR_FILE_EXISTS => return ErrorKind::AlreadyExists,
  69         c::ERROR_BROKEN_PIPE => return ErrorKind::BrokenPipe,
  70         c::ERROR_FILE_NOT_FOUND => return ErrorKind::NotFound,
  71         c::ERROR_PATH_NOT_FOUND => return ErrorKind::NotFound,
  72         c::ERROR_NO_DATA => return ErrorKind::BrokenPipe,
  73         c::ERROR_INVALID_PARAMETER => return ErrorKind::InvalidInput,
  74         c::ERROR_SEM_TIMEOUT
  75         | c::WAIT_TIMEOUT
  76         | c::ERROR_DRIVER_CANCEL_TIMEOUT
  77         | c::ERROR_OPERATION_ABORTED
  78         | c::ERROR_SERVICE_REQUEST_TIMEOUT
  79         | c::ERROR_COUNTER_TIMEOUT
  80         | c::ERROR_TIMEOUT
  81         | c::ERROR_RESOURCE_CALL_TIMED_OUT
  82         | c::ERROR_CTX_MODEM_RESPONSE_TIMEOUT
  83         | c::ERROR_CTX_CLIENT_QUERY_TIMEOUT
  84         | c::FRS_ERR_SYSVOL_POPULATE_TIMEOUT
  85         | c::ERROR_DS_TIMELIMIT_EXCEEDED
  86         | c::DNS_ERROR_RECORD_TIMED_OUT
  87         | c::ERROR_IPSEC_IKE_TIMED_OUT
  88         | c::ERROR_RUNLEVEL_SWITCH_TIMEOUT
  89         | c::ERROR_RUNLEVEL_SWITCH_AGENT_TIMEOUT => return ErrorKind::TimedOut,
  90         c::ERROR_CALL_NOT_IMPLEMENTED => return ErrorKind::Unsupported,
  91         _ => {}
  92     }
  93
  94     match errno {
  95         c::WSAEACCES => ErrorKind::PermissionDenied,
  96         c::WSAEADDRINUSE => ErrorKind::AddrInUse,
  97         c::WSAEADDRNOTAVAIL => ErrorKind::AddrNotAvailable,
  98         c::WSAECONNABORTED => ErrorKind::ConnectionAborted,
  99         c::WSAECONNREFUSED => ErrorKind::ConnectionRefused,
 100         c::WSAECONNRESET => ErrorKind::ConnectionReset,
 101         c::WSAEINVAL => ErrorKind::InvalidInput,
 102         c::WSAENOTCONN => ErrorKind::NotConnected,
 103         c::WSAEWOULDBLOCK => ErrorKind::WouldBlock,
 104         c::WSAETIMEDOUT => ErrorKind::TimedOut,
 105
 106         _ => ErrorKind::Other,
 107     }
 108 }
 109
 110 pub fn unrolled_find_u16s(needle: u16, haystack: &[u16]) -> Option<usize> {
 111     let ptr = haystack.as_ptr();
 112     let mut start = &haystack[..];
 113
 114     // For performance reasons unfold the loop eight times.
 115     while start.len() >= 8 {
 116         macro_rules! if_return {
 117             ($($n:literal,)+) => {
 118                 $(
 119                     if start[$n] == needle {
 120                         return Some((&start[$n] as *const u16 as usize - ptr as usize) / 2);
 121                     }
 122                 )+
 123             }
 124         }
 125
 126         if_return!(0, 1, 2, 3, 4, 5, 6, 7,);
 127
 128         start = &start[8..];
 129     }
 130
 131     for c in start {
 132         if *c == needle {
 133             return Some((c as *const u16 as usize - ptr as usize) / 2);
 134         }
 135     }
 136     None
 137 }
 138
 139 pub fn to_u16s<S: AsRef<OsStr>>(s: S) -> crate::io::Result<Vec<u16>> {
 140     fn inner(s: &OsStr) -> crate::io::Result<Vec<u16>> {
 141         let mut maybe_result: Vec<u16> = s.encode_wide().collect();
 142         if unrolled_find_u16s(0, &maybe_result).is_some() {
 143             return Err(crate::io::Error::new_const(
 144                 ErrorKind::InvalidInput,
 145                 &"strings passed to WinAPI cannot contain NULs",
 146             ));
 147         }
 148         maybe_result.push(0);
 149         Ok(maybe_result)
 150     }
 151     inner(s.as_ref())
 152 }
 153
 154 // Many Windows APIs follow a pattern of where we hand a buffer and then they
 155 // will report back to us how large the buffer should be or how many bytes
 156 // currently reside in the buffer. This function is an abstraction over these
 157 // functions by making them easier to call.
 158 //
 159 // The first callback, `f1`, is yielded a (pointer, len) pair which can be
 160 // passed to a syscall. The `ptr` is valid for `len` items (u16 in this case).
 161 // The closure is expected to return what the syscall returns which will be
 162 // interpreted by this function to determine if the syscall needs to be invoked
 163 // again (with more buffer space).
 164 //
 165 // Once the syscall has completed (errors bail out early) the second closure is
 166 // yielded the data which has been read from the syscall. The return value
 167 // from this closure is then the return value of the function.
 168 fn fill_utf16_buf<F1, F2, T>(mut f1: F1, f2: F2) -> crate::io::Result<T>
 169 where
 170     F1: FnMut(*mut u16, c::DWORD) -> c::DWORD,
 171     F2: FnOnce(&[u16]) -> T,
 172 {
 173     // Start off with a stack buf but then spill over to the heap if we end up
 174     // needing more space.
 175     let mut stack_buf = [0u16; 512];
 176     let mut heap_buf = Vec::new();
 177     unsafe {
 178         let mut n = stack_buf.len();
 179         loop {
 180             let buf = if n <= stack_buf.len() {
 181                 &mut stack_buf[..]
 182             } else {
 183                 let extra = n - heap_buf.len();
 184                 heap_buf.reserve(extra);
 185                 heap_buf.set_len(n);
 186                 &mut heap_buf[..]
 187             };
 188
 189             // This function is typically called on windows API functions which
 190             // will return the correct length of the string, but these functions
 191             // also return the `0` on error. In some cases, however, the
 192             // returned "correct length" may actually be 0!
 193             //
 194             // To handle this case we call `SetLastError` to reset it to 0 and
 195             // then check it again if we get the "0 error value". If the "last
 196             // error" is still 0 then we interpret it as a 0 length buffer and
 197             // not an actual error.
 198             c::SetLastError(0);
 199             let k = match f1(buf.as_mut_ptr(), n as c::DWORD) {
 200                 0 if c::GetLastError() == 0 => 0,
 201                 0 => return Err(crate::io::Error::last_os_error()),
 202                 n => n,
 203             } as usize;
 204             if k == n && c::GetLastError() == c::ERROR_INSUFFICIENT_BUFFER {
 205                 n *= 2;
 206             } else if k >= n {
 207                 n = k;
 208             } else {
 209                 return Ok(f2(&buf[..k]));
 210             }
 211         }
 212     }
 213 }
 214
 215 fn os2path(s: &[u16]) -> PathBuf {
 216     PathBuf::from(OsString::from_wide(s))
 217 }
 218
 219 pub fn truncate_utf16_at_nul(v: &[u16]) -> &[u16] {
 220     match unrolled_find_u16s(0, v) {
 221         // don't include the 0
 222         Some(i) => &v[..i],
 223         None => v,
 224     }
 225 }
 226
 227 pub trait IsZero {
 228     fn is_zero(&self) -> bool;
 229 }
 230
 231 macro_rules! impl_is_zero {
 232     ($($t:ident)*) => ($(impl IsZero for $t {
 233         fn is_zero(&self) -> bool {
 234             *self == 0
 235         }
 236     })*)
 237 }
 238
 239 impl_is_zero! { i8 i16 i32 i64 isize u8 u16 u32 u64 usize }
 240
 241 pub fn cvt<I: IsZero>(i: I) -> crate::io::Result<I> {
 242     if i.is_zero() { Err(crate::io::Error::last_os_error()) } else { Ok(i) }
 243 }
 244
 245 pub fn dur2timeout(dur: Duration) -> c::DWORD {
 246     // Note that a duration is a (u64, u32) (seconds, nanoseconds) pair, and the
 247     // timeouts in windows APIs are typically u32 milliseconds. To translate, we
 248     // have two pieces to take care of:
 249     //
 250     // * Nanosecond precision is rounded up
 251     // * Greater than u32::MAX milliseconds (50 days) is rounded up to INFINITE
 252     //   (never time out).
 253     dur.as_secs()
 254         .checked_mul(1000)
 255         .and_then(|ms| ms.checked_add((dur.subsec_nanos() as u64) / 1_000_000))
 256         .and_then(|ms| ms.checked_add(if dur.subsec_nanos() % 1_000_000 > 0 { 1 } else { 0 }))
 257         .map(|ms| if ms > <c::DWORD>::MAX as u64 { c::INFINITE } else { ms as c::DWORD })
 258         .unwrap_or(c::INFINITE)
 259 }
 260
 261 /// Use `__fastfail` to abort the process
 262 ///
 263 /// This is the same implementation as in libpanic_abort's `__rust_start_panic`. See
 264 /// that function for more information on `__fastfail`
 265 #[allow(unreachable_code)]
 266 pub fn abort_internal() -> ! {
 267     const FAST_FAIL_FATAL_APP_EXIT: usize = 7;
 268     unsafe {
 269         cfg_if::cfg_if! {
 270             if #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] {
 271                 asm!("int $$0x29", in("ecx") FAST_FAIL_FATAL_APP_EXIT);
 272                 crate::intrinsics::unreachable();
 273             } else if #[cfg(all(target_arch = "arm", target_feature = "thumb-mode"))] {
 274                 asm!(".inst 0xDEFB", in("r0") FAST_FAIL_FATAL_APP_EXIT);
 275                 crate::intrinsics::unreachable();
 276             } else if #[cfg(target_arch = "aarch64")] {
 277                 asm!("brk 0xF003", in("x0") FAST_FAIL_FATAL_APP_EXIT);
 278                 crate::intrinsics::unreachable();
 279             }
 280         }
 281     }
 282     crate::intrinsics::abort();
 283 }
 284
 285 cfg_if::cfg_if! {
 286     if #[cfg(target_vendor = "uwp")] {
 287         #[link(name = "ws2_32")]
 288         // For BCryptGenRandom
 289         #[link(name = "bcrypt")]
 290         extern "C" {}
 291     } else {
 292         #[link(name = "advapi32")]
 293         #[link(name = "ws2_32")]
 294         #[link(name = "userenv")]
 295         extern "C" {}
 296     }
 297 }