src/libstd/sys/windows/mod.rs

   1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![allow(missing_docs, bad_style)]
  12
  13 use ptr;
  14 use ffi::{OsStr, OsString};
  15 use io::{self, ErrorKind};
  16 use os::windows::ffi::{OsStrExt, OsStringExt};
  17 use path::PathBuf;
  18 use time::Duration;
  19
  20 pub use libc::strlen;
  21 pub use self::rand::hashmap_random_keys;
  22
  23 #[macro_use] pub mod compat;
  24
  25 pub mod args;
  26 #[cfg(feature = "backtrace")]
  27 pub mod backtrace;
  28 pub mod c;
  29 pub mod cmath;
  30 pub mod condvar;
  31 #[cfg(feature = "backtrace")]
  32 pub mod dynamic_lib;
  33 pub mod env;
  34 pub mod ext;
  35 pub mod fast_thread_local;
  36 pub mod fs;
  37 pub mod handle;
  38 pub mod memchr;
  39 pub mod mutex;
  40 pub mod net;
  41 pub mod os;
  42 pub mod os_str;
  43 pub mod path;
  44 pub mod pipe;
  45 pub mod process;
  46 pub mod rand;
  47 pub mod rwlock;
  48 pub mod stack_overflow;
  49 pub mod thread;
  50 pub mod thread_local;
  51 pub mod time;
  52 pub mod stdio;
  53
  54 #[cfg(not(test))]
  55 pub fn init() {
  56 }
  57
  58 pub fn decode_error_kind(errno: i32) -> ErrorKind {
  59     match errno as c::DWORD {
  60         c::ERROR_ACCESS_DENIED => return ErrorKind::PermissionDenied,
  61         c::ERROR_ALREADY_EXISTS => return ErrorKind::AlreadyExists,
  62         c::ERROR_FILE_EXISTS => return ErrorKind::AlreadyExists,
  63         c::ERROR_BROKEN_PIPE => return ErrorKind::BrokenPipe,
  64         c::ERROR_FILE_NOT_FOUND => return ErrorKind::NotFound,
  65         c::ERROR_PATH_NOT_FOUND => return ErrorKind::NotFound,
  66         c::ERROR_NO_DATA => return ErrorKind::BrokenPipe,
  67         c::ERROR_OPERATION_ABORTED => return ErrorKind::TimedOut,
  68         _ => {}
  69     }
  70
  71     match errno {
  72         c::WSAEACCES => ErrorKind::PermissionDenied,
  73         c::WSAEADDRINUSE => ErrorKind::AddrInUse,
  74         c::WSAEADDRNOTAVAIL => ErrorKind::AddrNotAvailable,
  75         c::WSAECONNABORTED => ErrorKind::ConnectionAborted,
  76         c::WSAECONNREFUSED => ErrorKind::ConnectionRefused,
  77         c::WSAECONNRESET => ErrorKind::ConnectionReset,
  78         c::WSAEINVAL => ErrorKind::InvalidInput,
  79         c::WSAENOTCONN => ErrorKind::NotConnected,
  80         c::WSAEWOULDBLOCK => ErrorKind::WouldBlock,
  81         c::WSAETIMEDOUT => ErrorKind::TimedOut,
  82
  83         _ => ErrorKind::Other,
  84     }
  85 }
  86
  87 pub fn to_u16s<S: AsRef<OsStr>>(s: S) -> io::Result<Vec<u16>> {
  88     fn inner(s: &OsStr) -> io::Result<Vec<u16>> {
  89         let mut maybe_result: Vec<u16> = s.encode_wide().collect();
  90         if maybe_result.iter().any(|&u| u == 0) {
  91             return Err(io::Error::new(io::ErrorKind::InvalidInput,
  92                                       "strings passed to WinAPI cannot contain NULs"));
  93         }
  94         maybe_result.push(0);
  95         Ok(maybe_result)
  96     }
  97     inner(s.as_ref())
  98 }
  99
 100 // Many Windows APIs follow a pattern of where we hand a buffer and then they
 101 // will report back to us how large the buffer should be or how many bytes
 102 // currently reside in the buffer. This function is an abstraction over these
 103 // functions by making them easier to call.
 104 //
 105 // The first callback, `f1`, is yielded a (pointer, len) pair which can be
 106 // passed to a syscall. The `ptr` is valid for `len` items (u16 in this case).
 107 // The closure is expected to return what the syscall returns which will be
 108 // interpreted by this function to determine if the syscall needs to be invoked
 109 // again (with more buffer space).
 110 //
 111 // Once the syscall has completed (errors bail out early) the second closure is
 112 // yielded the data which has been read from the syscall. The return value
 113 // from this closure is then the return value of the function.
 114 fn fill_utf16_buf<F1, F2, T>(mut f1: F1, f2: F2) -> io::Result<T>
 115     where F1: FnMut(*mut u16, c::DWORD) -> c::DWORD,
 116           F2: FnOnce(&[u16]) -> T
 117 {
 118     // Start off with a stack buf but then spill over to the heap if we end up
 119     // needing more space.
 120     let mut stack_buf = [0u16; 512];
 121     let mut heap_buf = Vec::new();
 122     unsafe {
 123         let mut n = stack_buf.len();
 124         loop {
 125             let buf = if n <= stack_buf.len() {
 126                 &mut stack_buf[..]
 127             } else {
 128                 let extra = n - heap_buf.len();
 129                 heap_buf.reserve(extra);
 130                 heap_buf.set_len(n);
 131                 &mut heap_buf[..]
 132             };
 133
 134             // This function is typically called on windows API functions which
 135             // will return the correct length of the string, but these functions
 136             // also return the `0` on error. In some cases, however, the
 137             // returned "correct length" may actually be 0!
 138             //
 139             // To handle this case we call `SetLastError` to reset it to 0 and
 140             // then check it again if we get the "0 error value". If the "last
 141             // error" is still 0 then we interpret it as a 0 length buffer and
 142             // not an actual error.
 143             c::SetLastError(0);
 144             let k = match f1(buf.as_mut_ptr(), n as c::DWORD) {
 145                 0 if c::GetLastError() == 0 => 0,
 146                 0 => return Err(io::Error::last_os_error()),
 147                 n => n,
 148             } as usize;
 149             if k == n && c::GetLastError() == c::ERROR_INSUFFICIENT_BUFFER {
 150                 n *= 2;
 151             } else if k >= n {
 152                 n = k;
 153             } else {
 154                 return Ok(f2(&buf[..k]))
 155             }
 156         }
 157     }
 158 }
 159
 160 fn os2path(s: &[u16]) -> PathBuf {
 161     PathBuf::from(OsString::from_wide(s))
 162 }
 163
 164 #[allow(dead_code)] // Only used in backtrace::gnu::get_executable_filename()
 165 fn wide_char_to_multi_byte(code_page: u32,
 166                            flags: u32,
 167                            s: &[u16],
 168                            no_default_char: bool)
 169                            -> io::Result<Vec<i8>> {
 170     unsafe {
 171         let mut size = c::WideCharToMultiByte(code_page,
 172                                               flags,
 173                                               s.as_ptr(),
 174                                               s.len() as i32,
 175                                               ptr::null_mut(),
 176                                               0,
 177                                               ptr::null(),
 178                                               ptr::null_mut());
 179         if size == 0 {
 180             return Err(io::Error::last_os_error());
 181         }
 182
 183         let mut buf = Vec::with_capacity(size as usize);
 184         buf.set_len(size as usize);
 185
 186         let mut used_default_char = c::FALSE;
 187         size = c::WideCharToMultiByte(code_page,
 188                                       flags,
 189                                       s.as_ptr(),
 190                                       s.len() as i32,
 191                                       buf.as_mut_ptr(),
 192                                       buf.len() as i32,
 193                                       ptr::null(),
 194                                       if no_default_char { &mut used_default_char }
 195                                       else { ptr::null_mut() });
 196         if size == 0 {
 197             return Err(io::Error::last_os_error());
 198         }
 199         if no_default_char && used_default_char == c::TRUE {
 200             return Err(io::Error::new(io::ErrorKind::InvalidData,
 201                                       "string cannot be converted to requested code page"));
 202         }
 203
 204         buf.set_len(size as usize);
 205
 206         Ok(buf)
 207     }
 208 }
 209
 210 pub fn truncate_utf16_at_nul<'a>(v: &'a [u16]) -> &'a [u16] {
 211     match v.iter().position(|c| *c == 0) {
 212         // don't include the 0
 213         Some(i) => &v[..i],
 214         None => v
 215     }
 216 }
 217
 218 pub trait IsZero {
 219     fn is_zero(&self) -> bool;
 220 }
 221
 222 macro_rules! impl_is_zero {
 223     ($($t:ident)*) => ($(impl IsZero for $t {
 224         fn is_zero(&self) -> bool {
 225             *self == 0
 226         }
 227     })*)
 228 }
 229
 230 impl_is_zero! { i8 i16 i32 i64 isize u8 u16 u32 u64 usize }
 231
 232 pub fn cvt<I: IsZero>(i: I) -> io::Result<I> {
 233     if i.is_zero() {
 234         Err(io::Error::last_os_error())
 235     } else {
 236         Ok(i)
 237     }
 238 }
 239
 240 pub fn dur2timeout(dur: Duration) -> c::DWORD {
 241     // Note that a duration is a (u64, u32) (seconds, nanoseconds) pair, and the
 242     // timeouts in windows APIs are typically u32 milliseconds. To translate, we
 243     // have two pieces to take care of:
 244     //
 245     // * Nanosecond precision is rounded up
 246     // * Greater than u32::MAX milliseconds (50 days) is rounded up to INFINITE
 247     //   (never time out).
 248     dur.as_secs().checked_mul(1000).and_then(|ms| {
 249         ms.checked_add((dur.subsec_nanos() as u64) / 1_000_000)
 250     }).and_then(|ms| {
 251         ms.checked_add(if dur.subsec_nanos() % 1_000_000 > 0 {1} else {0})
 252     }).map(|ms| {
 253         if ms > <c::DWORD>::max_value() as u64 {
 254             c::INFINITE
 255         } else {
 256             ms as c::DWORD
 257         }
 258     }).unwrap_or(c::INFINITE)
 259 }
 260
 261 // On Windows, use the processor-specific __fastfail mechanism.  In Windows 8
 262 // and later, this will terminate the process immediately without running any
 263 // in-process exception handlers.  In earlier versions of Windows, this
 264 // sequence of instructions will be treated as an access violation,
 265 // terminating the process but without necessarily bypassing all exception
 266 // handlers.
 267 //
 268 // https://msdn.microsoft.com/en-us/library/dn774154.aspx
 269 #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 270 pub unsafe fn abort_internal() -> ! {
 271     asm!("int $$0x29" :: "{ecx}"(7) ::: volatile); // 7 is FAST_FAIL_FATAL_APP_EXIT
 272     ::intrinsics::unreachable();
 273 }