1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #ifndef _FCNTL_H 30 #error "Never include this file directly; instead, include <fcntl.h>" 31 #endif 32 33 int __open_2(const char*, int) __INTRODUCED_IN(17); 34 int __openat_2(int, const char*, int) __INTRODUCED_IN(17); 35 /* 36 * These are the easiest way to call the real open even in clang FORTIFY. 37 */ 38 int __open_real(const char*, int, ...) __RENAME(open); 39 int __openat_real(int, const char*, int, ...) __RENAME(openat); 40 41 #if defined(__BIONIC_FORTIFY) 42 #define __open_too_many_args_error "too many arguments" 43 #define __open_too_few_args_error "called with O_CREAT or O_TMPFILE, but missing mode" 44 #define __open_useless_modes_warning "has superfluous mode bits; missing O_CREAT?" 45 /* O_TMPFILE shares bits with O_DIRECTORY. */ 46 #define __open_modes_useful(flags) (((flags) & O_CREAT) || ((flags) & O_TMPFILE) == O_TMPFILE) 47 #if defined(__clang__) 48 49 #if __ANDROID_API__ >= __ANDROID_API_J_MR1__ 50 __BIONIC_ERROR_FUNCTION_VISIBILITY 51 int open(const char* pathname, int flags, mode_t modes, ...) __overloadable 52 __errorattr(__open_too_many_args_error); 53 54 /* 55 * pass_object_size serves two purposes here, neither of which involve __bos: it 56 * disqualifies this function from having its address taken (so &open works), 57 * and it makes overload resolution prefer open(const char *, int) over 58 * open(const char *, int, ...). 59 */ 60 __BIONIC_FORTIFY_INLINE 61 int open(const char* const __pass_object_size pathname, int flags) 62 __overloadable 63 __clang_error_if(__open_modes_useful(flags), "'open' " __open_too_few_args_error) { 64 return __open_2(pathname, flags); 65 } 66 67 __BIONIC_FORTIFY_INLINE 68 int open(const char* const __pass_object_size pathname, int flags, mode_t modes) 69 __overloadable 70 __clang_warning_if(!__open_modes_useful(flags) && modes, 71 "'open' " __open_useless_modes_warning) { 72 return __open_real(pathname, flags, modes); 73 } 74 75 __BIONIC_ERROR_FUNCTION_VISIBILITY 76 int openat(int dirfd, const char* pathname, int flags, mode_t modes, ...) 77 __overloadable 78 __errorattr(__open_too_many_args_error); 79 80 __BIONIC_FORTIFY_INLINE 81 int openat(int dirfd, const char* const __pass_object_size pathname, int flags) 82 __overloadable 83 __clang_error_if(__open_modes_useful(flags), "'openat' " __open_too_few_args_error) { 84 return __openat_2(dirfd, pathname, flags); 85 } 86 87 __BIONIC_FORTIFY_INLINE 88 int openat(int dirfd, const char* const __pass_object_size pathname, int flags, mode_t modes) 89 __overloadable 90 __clang_warning_if(!__open_modes_useful(flags) && modes, 91 "'openat' " __open_useless_modes_warning) { 92 return __openat_real(dirfd, pathname, flags, modes); 93 } 94 #endif /* __ANDROID_API__ >= __ANDROID_API_J_MR1__ */ 95 96 #else /* defined(__clang__) */ 97 __errordecl(__creat_missing_mode, __open_too_few_args_error); 98 __errordecl(__creat_too_many_args, __open_too_many_args_error); 99 100 #if __ANDROID_API__ >= __ANDROID_API_J_MR1__ 101 __BIONIC_FORTIFY_VARIADIC 102 int open(const char* pathname, int flags, ...) { 103 if (__builtin_constant_p(flags)) { 104 if (__open_modes_useful(flags) && __builtin_va_arg_pack_len() == 0) { 105 __creat_missing_mode(); /* Compile time error. */ 106 } 107 } 108 109 if (__builtin_va_arg_pack_len() > 1) { 110 __creat_too_many_args(); /* Compile time error. */ 111 } 112 113 if ((__builtin_va_arg_pack_len() == 0) && !__builtin_constant_p(flags)) { 114 return __open_2(pathname, flags); 115 } 116 117 return __open_real(pathname, flags, __builtin_va_arg_pack()); 118 } 119 120 __BIONIC_FORTIFY_VARIADIC 121 int openat(int dirfd, const char* pathname, int flags, ...) { 122 if (__builtin_constant_p(flags)) { 123 if (__open_modes_useful(flags) && __builtin_va_arg_pack_len() == 0) { 124 __creat_missing_mode(); /* Compile time error. */ 125 } 126 } 127 128 if (__builtin_va_arg_pack_len() > 1) { 129 __creat_too_many_args(); /* Compile time error. */ 130 } 131 132 if ((__builtin_va_arg_pack_len() == 0) && !__builtin_constant_p(flags)) { 133 return __openat_2(dirfd, pathname, flags); 134 } 135 136 return __openat_real(dirfd, pathname, flags, __builtin_va_arg_pack()); 137 } 138 #endif /* __ANDROID_API__ >= __ANDROID_API_J_MR1__ */ 139 140 #endif /* defined(__clang__) */ 141 142 #undef __open_too_many_args_error 143 #undef __open_too_few_args_error 144 #undef __open_useless_modes_warning 145 #undef __open_modes_useful 146 #endif /* defined(__BIONIC_FORTIFY) */ 147
