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)]
  12 #![allow(non_camel_case_types)]
  13 #![allow(non_snake_case)]
  14
  15 use prelude::v1::*;
  16
  17 use ffi::{OsStr, OsString};
  18 use io::{self, ErrorKind};
  19 use num::Zero;
  20 use os::windows::ffi::{OsStrExt, OsStringExt};
  21 use path::PathBuf;
  22 use time::Duration;
  23
  24 #[macro_use] pub mod compat;
  25
  26 pub mod backtrace;
  27 pub mod c;
  28 pub mod condvar;
  29 pub mod ext;
  30 pub mod fs;
  31 pub mod handle;
  32 pub mod mutex;
  33 pub mod net;
  34 pub mod os;
  35 pub mod os_str;
  36 pub mod pipe;
  37 pub mod process;
  38 pub mod rwlock;
  39 pub mod stack_overflow;
  40 pub mod thread;
  41 pub mod thread_local;
  42 pub mod time;
  43 pub mod stdio;
  44
  45 pub fn init() {}
  46
  47 pub fn decode_error_kind(errno: i32) -> ErrorKind {
  48     match errno as c::DWORD {
  49         c::ERROR_ACCESS_DENIED => return ErrorKind::PermissionDenied,
  50         c::ERROR_ALREADY_EXISTS => return ErrorKind::AlreadyExists,
  51         c::ERROR_BROKEN_PIPE => return ErrorKind::BrokenPipe,
  52         c::ERROR_FILE_NOT_FOUND => return ErrorKind::NotFound,
  53         c::ERROR_PATH_NOT_FOUND => return ErrorKind::NotFound,
  54         c::ERROR_NO_DATA => return ErrorKind::BrokenPipe,
  55         c::ERROR_OPERATION_ABORTED => return ErrorKind::TimedOut,
  56         _ => {}
  57     }
  58
  59     match errno {
  60         c::WSAEACCES => ErrorKind::PermissionDenied,
  61         c::WSAEADDRINUSE => ErrorKind::AddrInUse,
  62         c::WSAEADDRNOTAVAIL => ErrorKind::AddrNotAvailable,
  63         c::WSAECONNABORTED => ErrorKind::ConnectionAborted,
  64         c::WSAECONNREFUSED => ErrorKind::ConnectionRefused,
  65         c::WSAECONNRESET => ErrorKind::ConnectionReset,
  66         c::WSAEINVAL => ErrorKind::InvalidInput,
  67         c::WSAENOTCONN => ErrorKind::NotConnected,
  68         c::WSAEWOULDBLOCK => ErrorKind::WouldBlock,
  69         c::WSAETIMEDOUT => ErrorKind::TimedOut,
  70
  71         _ => ErrorKind::Other,
  72     }
  73 }
  74
  75 pub fn to_u16s<S: AsRef<OsStr>>(s: S) -> io::Result<Vec<u16>> {
  76     fn inner(s: &OsStr) -> io::Result<Vec<u16>> {
  77         let mut maybe_result: Vec<u16> = s.encode_wide().collect();
  78         if maybe_result.iter().any(|&u| u == 0) {
  79             return Err(io::Error::new(io::ErrorKind::InvalidInput,
  80                                       "strings passed to WinAPI cannot contain NULs"));
  81         }
  82         maybe_result.push(0);
  83         Ok(maybe_result)
  84     }
  85     inner(s.as_ref())
  86 }
  87
  88 // Many Windows APIs follow a pattern of where we hand a buffer and then they
  89 // will report back to us how large the buffer should be or how many bytes
  90 // currently reside in the buffer. This function is an abstraction over these
  91 // functions by making them easier to call.
  92 //
  93 // The first callback, `f1`, is yielded a (pointer, len) pair which can be
  94 // passed to a syscall. The `ptr` is valid for `len` items (u16 in this case).
  95 // The closure is expected to return what the syscall returns which will be
  96 // interpreted by this function to determine if the syscall needs to be invoked
  97 // again (with more buffer space).
  98 //
  99 // Once the syscall has completed (errors bail out early) the second closure is
 100 // yielded the data which has been read from the syscall. The return value
 101 // from this closure is then the return value of the function.
 102 fn fill_utf16_buf<F1, F2, T>(mut f1: F1, f2: F2) -> io::Result<T>
 103     where F1: FnMut(*mut u16, c::DWORD) -> c::DWORD,
 104           F2: FnOnce(&[u16]) -> T
 105 {
 106     // Start off with a stack buf but then spill over to the heap if we end up
 107     // needing more space.
 108     let mut stack_buf = [0u16; 512];
 109     let mut heap_buf = Vec::new();
 110     unsafe {
 111         let mut n = stack_buf.len();
 112         loop {
 113             let buf = if n <= stack_buf.len() {
 114                 &mut stack_buf[..]
 115             } else {
 116                 let extra = n - heap_buf.len();
 117                 heap_buf.reserve(extra);
 118                 heap_buf.set_len(n);
 119                 &mut heap_buf[..]
 120             };
 121
 122             // This function is typically called on windows API functions which
 123             // will return the correct length of the string, but these functions
 124             // also return the `0` on error. In some cases, however, the
 125             // returned "correct length" may actually be 0!
 126             //
 127             // To handle this case we call `SetLastError` to reset it to 0 and
 128             // then check it again if we get the "0 error value". If the "last
 129             // error" is still 0 then we interpret it as a 0 length buffer and
 130             // not an actual error.
 131             c::SetLastError(0);
 132             let k = match f1(buf.as_mut_ptr(), n as c::DWORD) {
 133                 0 if c::GetLastError() == 0 => 0,
 134                 0 => return Err(io::Error::last_os_error()),
 135                 n => n,
 136             } as usize;
 137             if k == n && c::GetLastError() == c::ERROR_INSUFFICIENT_BUFFER {
 138                 n *= 2;
 139             } else if k >= n {
 140                 n = k;
 141             } else {
 142                 return Ok(f2(&buf[..k]))
 143             }
 144         }
 145     }
 146 }
 147
 148 fn os2path(s: &[u16]) -> PathBuf {
 149     PathBuf::from(OsString::from_wide(s))
 150 }
 151
 152 pub fn truncate_utf16_at_nul<'a>(v: &'a [u16]) -> &'a [u16] {
 153     match v.iter().position(|c| *c == 0) {
 154         // don't include the 0
 155         Some(i) => &v[..i],
 156         None => v
 157     }
 158 }
 159
 160 fn cvt<I: PartialEq + Zero>(i: I) -> io::Result<I> {
 161     if i == I::zero() {
 162         Err(io::Error::last_os_error())
 163     } else {
 164         Ok(i)
 165     }
 166 }
 167
 168 fn dur2timeout(dur: Duration) -> c::DWORD {
 169     // Note that a duration is a (u64, u32) (seconds, nanoseconds) pair, and the
 170     // timeouts in windows APIs are typically u32 milliseconds. To translate, we
 171     // have two pieces to take care of:
 172     //
 173     // * Nanosecond precision is rounded up
 174     // * Greater than u32::MAX milliseconds (50 days) is rounded up to INFINITE
 175     //   (never time out).
 176     dur.as_secs().checked_mul(1000).and_then(|ms| {
 177         ms.checked_add((dur.subsec_nanos() as u64) / 1_000_000)
 178     }).and_then(|ms| {
 179         ms.checked_add(if dur.subsec_nanos() % 1_000_000 > 0 {1} else {0})
 180     }).map(|ms| {
 181         if ms > <c::DWORD>::max_value() as u64 {
 182             c::INFINITE
 183         } else {
 184             ms as c::DWORD
 185         }
 186     }).unwrap_or(c::INFINITE)
 187 }