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 #[macro_use] pub mod compat;
  26
  27 pub mod backtrace;
  28 pub mod c;
  29 pub mod condvar;
  30 pub mod ext;
  31 pub mod fs;
  32 pub mod handle;
  33 pub mod mutex;
  34 pub mod net;
  35 pub mod os;
  36 pub mod os_str;
  37 pub mod pipe;
  38 pub mod process;
  39 pub mod rwlock;
  40 pub mod stack_overflow;
  41 pub mod thread;
  42 pub mod thread_local;
  43 pub mod time;
  44 pub mod stdio;
  45
  46 pub fn decode_error_kind(errno: i32) -> ErrorKind {
  47     match errno as libc::c_int {
  48         libc::ERROR_ACCESS_DENIED => ErrorKind::PermissionDenied,
  49         libc::ERROR_ALREADY_EXISTS => ErrorKind::AlreadyExists,
  50         libc::ERROR_BROKEN_PIPE => ErrorKind::BrokenPipe,
  51         libc::ERROR_FILE_NOT_FOUND => ErrorKind::NotFound,
  52         libc::ERROR_NO_DATA => ErrorKind::BrokenPipe,
  53         libc::ERROR_OPERATION_ABORTED => ErrorKind::TimedOut,
  54
  55         libc::WSAEACCES => ErrorKind::PermissionDenied,
  56         libc::WSAEADDRINUSE => ErrorKind::AddrInUse,
  57         libc::WSAEADDRNOTAVAIL => ErrorKind::AddrNotAvailable,
  58         libc::WSAECONNABORTED => ErrorKind::ConnectionAborted,
  59         libc::WSAECONNREFUSED => ErrorKind::ConnectionRefused,
  60         libc::WSAECONNRESET => ErrorKind::ConnectionReset,
  61         libc::WSAEINVAL => ErrorKind::InvalidInput,
  62         libc::WSAENOTCONN => ErrorKind::NotConnected,
  63         libc::WSAEWOULDBLOCK => ErrorKind::WouldBlock,
  64         libc::WSAETIMEDOUT => ErrorKind::TimedOut,
  65
  66         _ => ErrorKind::Other,
  67     }
  68 }
  69
  70 fn to_utf16_os(s: &OsStr) -> Vec<u16> {
  71     let mut v: Vec<_> = s.encode_wide().collect();
  72     v.push(0);
  73     v
  74 }
  75
  76 // Many Windows APIs follow a pattern of where we hand the a buffer and then
  77 // they will report back to us how large the buffer should be or how many bytes
  78 // currently reside in the buffer. This function is an abstraction over these
  79 // functions by making them easier to call.
  80 //
  81 // The first callback, `f1`, is yielded a (pointer, len) pair which can be
  82 // passed to a syscall. The `ptr` is valid for `len` items (u16 in this case).
  83 // The closure is expected to return what the syscall returns which will be
  84 // interpreted by this function to determine if the syscall needs to be invoked
  85 // again (with more buffer space).
  86 //
  87 // Once the syscall has completed (errors bail out early) the second closure is
  88 // yielded the data which has been read from the syscall. The return value
  89 // from this closure is then the return value of the function.
  90 fn fill_utf16_buf<F1, F2, T>(mut f1: F1, f2: F2) -> io::Result<T>
  91     where F1: FnMut(*mut u16, libc::DWORD) -> libc::DWORD,
  92           F2: FnOnce(&[u16]) -> T
  93 {
  94     // Start off with a stack buf but then spill over to the heap if we end up
  95     // needing more space.
  96     let mut stack_buf = [0u16; 512];
  97     let mut heap_buf = Vec::new();
  98     unsafe {
  99         let mut n = stack_buf.len();
 100         loop {
 101             let buf = if n <= stack_buf.len() {
 102                 &mut stack_buf[..]
 103             } else {
 104                 let extra = n - heap_buf.len();
 105                 heap_buf.reserve(extra);
 106                 heap_buf.set_len(n);
 107                 &mut heap_buf[..]
 108             };
 109
 110             // This function is typically called on windows API functions which
 111             // will return the correct length of the string, but these functions
 112             // also return the `0` on error. In some cases, however, the
 113             // returned "correct length" may actually be 0!
 114             //
 115             // To handle this case we call `SetLastError` to reset it to 0 and
 116             // then check it again if we get the "0 error value". If the "last
 117             // error" is still 0 then we interpret it as a 0 length buffer and
 118             // not an actual error.
 119             c::SetLastError(0);
 120             let k = match f1(buf.as_mut_ptr(), n as libc::DWORD) {
 121                 0 if libc::GetLastError() == 0 => 0,
 122                 0 => return Err(io::Error::last_os_error()),
 123                 n => n,
 124             } as usize;
 125             if k == n && libc::GetLastError() ==
 126                             libc::ERROR_INSUFFICIENT_BUFFER as libc::DWORD {
 127                 n *= 2;
 128             } else if k >= n {
 129                 n = k;
 130             } else {
 131                 return Ok(f2(&buf[..k]))
 132             }
 133         }
 134     }
 135 }
 136
 137 fn os2path(s: &[u16]) -> PathBuf {
 138     PathBuf::from(OsString::from_wide(s))
 139 }
 140
 141 pub fn truncate_utf16_at_nul<'a>(v: &'a [u16]) -> &'a [u16] {
 142     match v.iter().position(|c| *c == 0) {
 143         // don't include the 0
 144         Some(i) => &v[..i],
 145         None => v
 146     }
 147 }
 148
 149 fn cvt<I: PartialEq + Zero>(i: I) -> io::Result<I> {
 150     if i == I::zero() {
 151         Err(io::Error::last_os_error())
 152     } else {
 153         Ok(i)
 154     }
 155 }
 156
 157 fn dur2timeout(dur: Duration) -> libc::DWORD {
 158     // Note that a duration is a (u64, u32) (seconds, nanoseconds) pair, and the
 159     // timeouts in windows APIs are typically u32 milliseconds. To translate, we
 160     // have two pieces to take care of:
 161     //
 162     // * Nanosecond precision is rounded up
 163     // * Greater than u32::MAX milliseconds (50 days) is rounded up to INFINITE
 164     //   (never time out).
 165     dur.as_secs().checked_mul(1000).and_then(|ms| {
 166         ms.checked_add((dur.subsec_nanos() as u64) / 1_000_000)
 167     }).and_then(|ms| {
 168         ms.checked_add(if dur.subsec_nanos() % 1_000_000 > 0 {1} else {0})
 169     }).map(|ms| {
 170         if ms > <libc::DWORD>::max_value() as u64 {
 171             libc::INFINITE
 172         } else {
 173             ms as libc::DWORD
 174         }
 175     }).unwrap_or(libc::INFINITE)
 176 }
 177
 178 fn ms_to_filetime(ms: u64) -> libc::FILETIME {
 179     // A FILETIME is a count of 100 nanosecond intervals, so we multiply by
 180     // 10000 b/c there are 10000 intervals in 1 ms
 181     let ms = ms * 10000;
 182     libc::FILETIME {
 183         dwLowDateTime: ms as u32,
 184         dwHighDateTime: (ms >> 32) as u32,
 185     }
 186 }