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 libc;
  20 use num::Zero;
  21 use os::windows::ffi::{OsStrExt, OsStringExt};
  22 use path::PathBuf;
  23 use time::Duration;
  24
  25 pub mod backtrace;
  26 pub mod c;
  27 pub mod condvar;
  28 pub mod ext;
  29 pub mod fs;
  30 pub mod handle;
  31 pub mod mutex;
  32 pub mod net;
  33 pub mod os;
  34 pub mod os_str;
  35 pub mod pipe;
  36 pub mod process;
  37 pub mod rwlock;
  38 pub mod stack_overflow;
  39 pub mod sync;
  40 pub mod thread;
  41 pub mod thread_local;
  42 pub mod time;
  43 pub mod stdio;
  44
  45 pub fn decode_error_kind(errno: i32) -> ErrorKind {
  46     match errno as libc::c_int {
  47         libc::ERROR_ACCESS_DENIED => ErrorKind::PermissionDenied,
  48         libc::ERROR_ALREADY_EXISTS => ErrorKind::AlreadyExists,
  49         libc::ERROR_BROKEN_PIPE => ErrorKind::BrokenPipe,
  50         libc::ERROR_FILE_NOT_FOUND => ErrorKind::NotFound,
  51         libc::ERROR_NO_DATA => ErrorKind::BrokenPipe,
  52         libc::ERROR_OPERATION_ABORTED => ErrorKind::TimedOut,
  53
  54         libc::WSAEACCES => ErrorKind::PermissionDenied,
  55         libc::WSAEADDRINUSE => ErrorKind::AddrInUse,
  56         libc::WSAEADDRNOTAVAIL => ErrorKind::AddrNotAvailable,
  57         libc::WSAECONNABORTED => ErrorKind::ConnectionAborted,
  58         libc::WSAECONNREFUSED => ErrorKind::ConnectionRefused,
  59         libc::WSAECONNRESET => ErrorKind::ConnectionReset,
  60         libc::WSAEINVAL => ErrorKind::InvalidInput,
  61         libc::WSAENOTCONN => ErrorKind::NotConnected,
  62         libc::WSAEWOULDBLOCK => ErrorKind::WouldBlock,
  63         libc::WSAETIMEDOUT => ErrorKind::TimedOut,
  64
  65         _ => ErrorKind::Other,
  66     }
  67 }
  68
  69 fn to_utf16_os(s: &OsStr) -> Vec<u16> {
  70     let mut v: Vec<_> = s.encode_wide().collect();
  71     v.push(0);
  72     v
  73 }
  74
  75 // Many Windows APIs follow a pattern of where we hand the a buffer and then
  76 // they will report back to us how large the buffer should be or how many bytes
  77 // currently reside in the buffer. This function is an abstraction over these
  78 // functions by making them easier to call.
  79 //
  80 // The first callback, `f1`, is yielded a (pointer, len) pair which can be
  81 // passed to a syscall. The `ptr` is valid for `len` items (u16 in this case).
  82 // The closure is expected to return what the syscall returns which will be
  83 // interpreted by this function to determine if the syscall needs to be invoked
  84 // again (with more buffer space).
  85 //
  86 // Once the syscall has completed (errors bail out early) the second closure is
  87 // yielded the data which has been read from the syscall. The return value
  88 // from this closure is then the return value of the function.
  89 fn fill_utf16_buf<F1, F2, T>(mut f1: F1, f2: F2) -> io::Result<T>
  90     where F1: FnMut(*mut u16, libc::DWORD) -> libc::DWORD,
  91           F2: FnOnce(&[u16]) -> T
  92 {
  93     // Start off with a stack buf but then spill over to the heap if we end up
  94     // needing more space.
  95     let mut stack_buf = [0u16; 512];
  96     let mut heap_buf = Vec::new();
  97     unsafe {
  98         let mut n = stack_buf.len();
  99         loop {
 100             let buf = if n <= stack_buf.len() {
 101                 &mut stack_buf[..]
 102             } else {
 103                 let extra = n - heap_buf.len();
 104                 heap_buf.reserve(extra);
 105                 heap_buf.set_len(n);
 106                 &mut heap_buf[..]
 107             };
 108
 109             // This function is typically called on windows API functions which
 110             // will return the correct length of the string, but these functions
 111             // also return the `0` on error. In some cases, however, the
 112             // returned "correct length" may actually be 0!
 113             //
 114             // To handle this case we call `SetLastError` to reset it to 0 and
 115             // then check it again if we get the "0 error value". If the "last
 116             // error" is still 0 then we interpret it as a 0 length buffer and
 117             // not an actual error.
 118             c::SetLastError(0);
 119             let k = match f1(buf.as_mut_ptr(), n as libc::DWORD) {
 120                 0 if libc::GetLastError() == 0 => 0,
 121                 0 => return Err(io::Error::last_os_error()),
 122                 n => n,
 123             } as usize;
 124             if k == n && libc::GetLastError() ==
 125                             libc::ERROR_INSUFFICIENT_BUFFER as libc::DWORD {
 126                 n *= 2;
 127             } else if k >= n {
 128                 n = k;
 129             } else {
 130                 return Ok(f2(&buf[..k]))
 131             }
 132         }
 133     }
 134 }
 135
 136 fn os2path(s: &[u16]) -> PathBuf {
 137     PathBuf::from(OsString::from_wide(s))
 138 }
 139
 140 pub fn truncate_utf16_at_nul<'a>(v: &'a [u16]) -> &'a [u16] {
 141     match v.iter().position(|c| *c == 0) {
 142         // don't include the 0
 143         Some(i) => &v[..i],
 144         None => v
 145     }
 146 }
 147
 148 fn cvt<I: PartialEq + Zero>(i: I) -> io::Result<I> {
 149     if i == I::zero() {
 150         Err(io::Error::last_os_error())
 151     } else {
 152         Ok(i)
 153     }
 154 }
 155
 156 fn dur2timeout(dur: Duration) -> libc::DWORD {
 157     // Note that a duration is a (u64, u32) (seconds, nanoseconds) pair, and the
 158     // timeouts in windows APIs are typically u32 milliseconds. To translate, we
 159     // have two pieces to take care of:
 160     //
 161     // * Nanosecond precision is rounded up
 162     // * Greater than u32::MAX milliseconds (50 days) is rounded up to INFINITE
 163     //   (never time out).
 164     dur.secs().checked_mul(1000).and_then(|ms| {
 165         ms.checked_add((dur.extra_nanos() as u64) / 1_000_000)
 166     }).and_then(|ms| {
 167         ms.checked_add(if dur.extra_nanos() % 1_000_000 > 0 {1} else {0})
 168     }).map(|ms| {
 169         if ms > <libc::DWORD>::max_value() as u64 {
 170             libc::INFINITE
 171         } else {
 172             ms as libc::DWORD
 173         }
 174     }).unwrap_or(libc::INFINITE)
 175 }
 176
 177 fn ms_to_filetime(ms: u64) -> libc::FILETIME {
 178     // A FILETIME is a count of 100 nanosecond intervals, so we multiply by
 179     // 10000 b/c there are 10000 intervals in 1 ms
 180     let ms = ms * 10000;
 181     libc::FILETIME {
 182         dwLowDateTime: ms as u32,
 183         dwHighDateTime: (ms >> 32) as u32,
 184     }
 185 }