summaryrefslogtreecommitdiffstats
path: root/third_party/rust/gcc/src/registry.rs
blob: d871cd21f3c06d69e40a3c332e91fd97323b1d8b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

use std::ffi::{OsString, OsStr};
use std::io;
use std::ops::RangeFrom;
use std::os::raw;
use std::os::windows::prelude::*;

pub struct RegistryKey(Repr);

type HKEY = *mut u8;
type DWORD = u32;
type LPDWORD = *mut DWORD;
type LPCWSTR = *const u16;
type LPWSTR = *mut u16;
type LONG = raw::c_long;
type PHKEY = *mut HKEY;
type PFILETIME = *mut u8;
type LPBYTE = *mut u8;
type REGSAM = u32;

const ERROR_SUCCESS: DWORD = 0;
const ERROR_NO_MORE_ITEMS: DWORD = 259;
const HKEY_LOCAL_MACHINE: HKEY = 0x80000002 as HKEY;
const REG_SZ: DWORD = 1;
const KEY_READ: DWORD = 0x20019;
const KEY_WOW64_32KEY: DWORD = 0x200;

#[link(name = "advapi32")]
extern "system" {
    fn RegOpenKeyExW(key: HKEY,
                     lpSubKey: LPCWSTR,
                     ulOptions: DWORD,
                     samDesired: REGSAM,
                     phkResult: PHKEY) -> LONG;
    fn RegEnumKeyExW(key: HKEY,
                     dwIndex: DWORD,
                     lpName: LPWSTR,
                     lpcName: LPDWORD,
                     lpReserved: LPDWORD,
                     lpClass: LPWSTR,
                     lpcClass: LPDWORD,
                     lpftLastWriteTime: PFILETIME) -> LONG;
    fn RegQueryValueExW(hKey: HKEY,
                        lpValueName: LPCWSTR,
                        lpReserved: LPDWORD,
                        lpType: LPDWORD,
                        lpData: LPBYTE,
                        lpcbData: LPDWORD) -> LONG;
    fn RegCloseKey(hKey: HKEY) -> LONG;
}

struct OwnedKey(HKEY);

enum Repr {
    Const(HKEY),
    Owned(OwnedKey),
}

pub struct Iter<'a> {
    idx: RangeFrom<DWORD>,
    key: &'a RegistryKey,
}

unsafe impl Sync for Repr {}
unsafe impl Send for Repr {}

pub static LOCAL_MACHINE: RegistryKey =
    RegistryKey(Repr::Const(HKEY_LOCAL_MACHINE));

impl RegistryKey {
    fn raw(&self) -> HKEY {
        match self.0 {
            Repr::Const(val) => val,
            Repr::Owned(ref val) => val.0,
        }
    }

    pub fn open(&self, key: &OsStr) -> io::Result<RegistryKey> {
        let key = key.encode_wide().chain(Some(0)).collect::<Vec<_>>();
        let mut ret = 0 as *mut _;
        let err = unsafe {
            RegOpenKeyExW(self.raw(), key.as_ptr(), 0,
                          KEY_READ | KEY_WOW64_32KEY, &mut ret)
        };
        if err == ERROR_SUCCESS as LONG {
            Ok(RegistryKey(Repr::Owned(OwnedKey(ret))))
        } else {
            Err(io::Error::from_raw_os_error(err as i32))
        }
    }

    pub fn iter(&self) -> Iter {
        Iter { idx: 0.., key: self }
    }

    pub fn query_str(&self, name: &str) -> io::Result<OsString> {
        let name: &OsStr = name.as_ref();
        let name = name.encode_wide().chain(Some(0)).collect::<Vec<_>>();
        let mut len = 0;
        let mut kind = 0;
        unsafe {
            let err = RegQueryValueExW(self.raw(), name.as_ptr(), 0 as *mut _,
                                       &mut kind, 0 as *mut _, &mut len);
            if err != ERROR_SUCCESS as LONG {
                return Err(io::Error::from_raw_os_error(err as i32))
            }
            if kind != REG_SZ {
                return Err(io::Error::new(io::ErrorKind::Other,
                                          "registry key wasn't a string"))
            }

            // The length here is the length in bytes, but we're using wide
            // characters so we need to be sure to halve it for the capacity
            // passed in.
            let mut v = Vec::with_capacity(len as usize / 2);
            let err = RegQueryValueExW(self.raw(), name.as_ptr(), 0 as *mut _,
                                       0 as *mut _, v.as_mut_ptr() as *mut _,
                                       &mut len);
            if err != ERROR_SUCCESS as LONG {
                return Err(io::Error::from_raw_os_error(err as i32))
            }
            v.set_len(len as usize / 2);

            // Some registry keys may have a terminating nul character, but
            // we're not interested in that, so chop it off if it's there.
            if v[v.len() - 1] == 0 {
                v.pop();
            }
            Ok(OsString::from_wide(&v))
        }
    }
}

impl Drop for OwnedKey {
    fn drop(&mut self) {
        unsafe { RegCloseKey(self.0); }
    }
}

impl<'a> Iterator for Iter<'a> {
    type Item = io::Result<OsString>;

    fn next(&mut self) -> Option<io::Result<OsString>> {
        self.idx.next().and_then(|i| unsafe {
            let mut v = Vec::with_capacity(256);
            let mut len = v.capacity() as DWORD;
            let ret = RegEnumKeyExW(self.key.raw(), i, v.as_mut_ptr(), &mut len,
                                    0 as *mut _, 0 as *mut _, 0 as *mut _,
                                    0 as *mut _);
            if ret == ERROR_NO_MORE_ITEMS as LONG {
                None
            } else if ret != ERROR_SUCCESS as LONG {
                Some(Err(io::Error::from_raw_os_error(ret as i32)))
            } else {
                v.set_len(len as usize);
                Some(Ok(OsString::from_wide(&v)))
            }
        })
    }
}