1 /* scoped_fd, automatically close a file descriptor 2 3 Copyright (C) 2018-2024 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 19 20 #ifndef COMMON_SCOPED_FD_H 21 #define COMMON_SCOPED_FD_H 22 23 #include <unistd.h> 24 #include "gdb_file.h" 25 26 /* A smart-pointer-like class to automatically close a file descriptor. */ 27 28 class scoped_fd 29 { 30 public: 31 explicit scoped_fd (int fd = -1) noexcept : m_fd (fd) {} 32 33 scoped_fd (scoped_fd &&other) noexcept 34 : m_fd (other.m_fd) 35 { 36 other.m_fd = -1; 37 } 38 39 ~scoped_fd () 40 { 41 if (m_fd >= 0) 42 close (m_fd); 43 } 44 45 scoped_fd &operator= (scoped_fd &&other) 46 { 47 if (m_fd != other.m_fd) 48 { 49 if (m_fd >= 0) 50 close (m_fd); 51 m_fd = other.m_fd; 52 other.m_fd = -1; 53 } 54 return *this; 55 } 56 57 DISABLE_COPY_AND_ASSIGN (scoped_fd); 58 59 ATTRIBUTE_UNUSED_RESULT int release () noexcept 60 { 61 int fd = m_fd; 62 m_fd = -1; 63 return fd; 64 } 65 66 /* Like release, but return a gdb_file_up that owns the file 67 descriptor. On success, this scoped_fd will be released. On 68 failure, return NULL and leave this scoped_fd in possession of 69 the fd. */ 70 gdb_file_up to_file (const char *mode) noexcept 71 { 72 gdb_file_up result (fdopen (m_fd, mode)); 73 if (result != nullptr) 74 m_fd = -1; 75 return result; 76 } 77 78 int get () const noexcept 79 { 80 return m_fd; 81 } 82 83 private: 84 int m_fd; 85 }; 86 87 #endif /* COMMON_SCOPED_FD_H */ 88