xref: /aosp_15_r20/bionic/libc/private/ScopedFd.h (revision 8d67ca893c1523eb926b9080dbe4e2ffd2a27ba1)
1*8d67ca89SAndroid Build Coastguard Worker /*
2*8d67ca89SAndroid Build Coastguard Worker  * Copyright (C) 2019 The Android Open Source Project
3*8d67ca89SAndroid Build Coastguard Worker  * All rights reserved.
4*8d67ca89SAndroid Build Coastguard Worker  *
5*8d67ca89SAndroid Build Coastguard Worker  * Redistribution and use in source and binary forms, with or without
6*8d67ca89SAndroid Build Coastguard Worker  * modification, are permitted provided that the following conditions
7*8d67ca89SAndroid Build Coastguard Worker  * are met:
8*8d67ca89SAndroid Build Coastguard Worker  *  * Redistributions of source code must retain the above copyright
9*8d67ca89SAndroid Build Coastguard Worker  *    notice, this list of conditions and the following disclaimer.
10*8d67ca89SAndroid Build Coastguard Worker  *  * Redistributions in binary form must reproduce the above copyright
11*8d67ca89SAndroid Build Coastguard Worker  *    notice, this list of conditions and the following disclaimer in
12*8d67ca89SAndroid Build Coastguard Worker  *    the documentation and/or other materials provided with the
13*8d67ca89SAndroid Build Coastguard Worker  *    distribution.
14*8d67ca89SAndroid Build Coastguard Worker  *
15*8d67ca89SAndroid Build Coastguard Worker  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16*8d67ca89SAndroid Build Coastguard Worker  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17*8d67ca89SAndroid Build Coastguard Worker  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18*8d67ca89SAndroid Build Coastguard Worker  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19*8d67ca89SAndroid Build Coastguard Worker  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20*8d67ca89SAndroid Build Coastguard Worker  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21*8d67ca89SAndroid Build Coastguard Worker  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22*8d67ca89SAndroid Build Coastguard Worker  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23*8d67ca89SAndroid Build Coastguard Worker  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24*8d67ca89SAndroid Build Coastguard Worker  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25*8d67ca89SAndroid Build Coastguard Worker  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26*8d67ca89SAndroid Build Coastguard Worker  * SUCH DAMAGE.
27*8d67ca89SAndroid Build Coastguard Worker  */
28*8d67ca89SAndroid Build Coastguard Worker 
29*8d67ca89SAndroid Build Coastguard Worker #pragma once
30*8d67ca89SAndroid Build Coastguard Worker 
31*8d67ca89SAndroid Build Coastguard Worker #include <unistd.h>
32*8d67ca89SAndroid Build Coastguard Worker 
33*8d67ca89SAndroid Build Coastguard Worker #include "platform/bionic/macros.h"
34*8d67ca89SAndroid Build Coastguard Worker #include "private/ErrnoRestorer.h"
35*8d67ca89SAndroid Build Coastguard Worker 
36*8d67ca89SAndroid Build Coastguard Worker class ScopedFd final {
37*8d67ca89SAndroid Build Coastguard Worker  public:
ScopedFd(int fd)38*8d67ca89SAndroid Build Coastguard Worker   explicit ScopedFd(int fd) : fd_(fd) {
39*8d67ca89SAndroid Build Coastguard Worker   }
40*8d67ca89SAndroid Build Coastguard Worker 
ScopedFd()41*8d67ca89SAndroid Build Coastguard Worker   ScopedFd() : fd_(-1) {
42*8d67ca89SAndroid Build Coastguard Worker   }
43*8d67ca89SAndroid Build Coastguard Worker 
~ScopedFd()44*8d67ca89SAndroid Build Coastguard Worker   ~ScopedFd() {
45*8d67ca89SAndroid Build Coastguard Worker     reset(-1);
46*8d67ca89SAndroid Build Coastguard Worker   }
47*8d67ca89SAndroid Build Coastguard Worker 
48*8d67ca89SAndroid Build Coastguard Worker   void reset(int fd = -1) {
49*8d67ca89SAndroid Build Coastguard Worker     if (fd_ != -1) {
50*8d67ca89SAndroid Build Coastguard Worker       ErrnoRestorer e;
51*8d67ca89SAndroid Build Coastguard Worker       close(fd_);
52*8d67ca89SAndroid Build Coastguard Worker     }
53*8d67ca89SAndroid Build Coastguard Worker     fd_ = fd;
54*8d67ca89SAndroid Build Coastguard Worker   }
55*8d67ca89SAndroid Build Coastguard Worker 
get()56*8d67ca89SAndroid Build Coastguard Worker   int get() const {
57*8d67ca89SAndroid Build Coastguard Worker     return fd_;
58*8d67ca89SAndroid Build Coastguard Worker   }
59*8d67ca89SAndroid Build Coastguard Worker 
60*8d67ca89SAndroid Build Coastguard Worker  private:
61*8d67ca89SAndroid Build Coastguard Worker   int fd_;
62*8d67ca89SAndroid Build Coastguard Worker 
63*8d67ca89SAndroid Build Coastguard Worker   BIONIC_DISALLOW_COPY_AND_ASSIGN(ScopedFd);
64*8d67ca89SAndroid Build Coastguard Worker };
65