| 1 | /* Copyright (C) 2015-2022 Free Software Foundation, Inc. |
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| 2 | This file is part of the GNU C Library. |
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| 3 | |
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| 4 | The GNU C Library is free software; you can redistribute it and/or |
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| 5 | modify it under the terms of the GNU Lesser General Public |
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| 6 | License as published by the Free Software Foundation; either |
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| 7 | version 2.1 of the License, or (at your option) any later version. |
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| 8 | |
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| 9 | The GNU C Library is distributed in the hope that it will be useful, |
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| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 12 | Lesser General Public License for more details. |
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| 13 | |
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| 14 | You should have received a copy of the GNU Lesser General Public |
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| 15 | License along with the GNU C Library; if not, see |
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| 16 | <https://www.gnu.org/licenses/>. */ |
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| 17 | |
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| 18 | #ifndef _SYSDEP_LINUX_H |
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| 19 | #define _SYSDEP_LINUX_H |
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| 20 | |
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| 21 | #include <bits/wordsize.h> |
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| 22 | #include <kernel-features.h> |
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| 23 | #include <endian.h> |
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| 24 | #include <errno.h> |
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| 25 | |
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| 26 | #undef INTERNAL_SYSCALL_ERROR_P |
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| 27 | #define INTERNAL_SYSCALL_ERROR_P(val) \ |
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| 28 | ((unsigned long int) (val) > -4096UL) |
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| 29 | |
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| 30 | #ifndef SYSCALL_ERROR_LABEL |
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| 31 | # define SYSCALL_ERROR_LABEL(sc_err) \ |
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| 32 | ({ \ |
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| 33 | __set_errno (sc_err); \ |
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| 34 | -1L; \ |
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| 35 | }) |
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| 36 | #endif |
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| 37 | |
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| 38 | /* Define a macro which expands into the inline wrapper code for a system |
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| 39 | call. It sets the errno and returns -1 on a failure, or the syscall |
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| 40 | return value otherwise. */ |
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| 41 | #undef INLINE_SYSCALL |
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| 42 | #define INLINE_SYSCALL(name, nr, args...) \ |
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| 43 | ({ \ |
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| 44 | long int sc_ret = INTERNAL_SYSCALL (name, nr, args); \ |
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| 45 | __glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (sc_ret)) \ |
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| 46 | ? SYSCALL_ERROR_LABEL (INTERNAL_SYSCALL_ERRNO (sc_ret)) \ |
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| 47 | : sc_ret; \ |
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| 48 | }) |
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| 49 | |
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| 50 | #undef INTERNAL_SYSCALL_ERRNO |
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| 51 | #define INTERNAL_SYSCALL_ERRNO(val) (-(val)) |
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| 52 | |
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| 53 | /* Set error number and return -1. A target may choose to return the |
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| 54 | internal function, __syscall_error, which sets errno and returns -1. |
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| 55 | We use -1l, instead of -1, so that it can be casted to (void *). */ |
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| 56 | #define INLINE_SYSCALL_ERROR_RETURN_VALUE(err) \ |
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| 57 | ({ \ |
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| 58 | __set_errno (err); \ |
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| 59 | -1l; \ |
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| 60 | }) |
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| 61 | |
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| 62 | /* Provide a dummy argument that can be used to force register |
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| 63 | alignment for register pairs if required by the syscall ABI. */ |
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| 64 | #ifdef __ASSUME_ALIGNED_REGISTER_PAIRS |
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| 65 | #define __ALIGNMENT_ARG 0, |
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| 66 | #define __ALIGNMENT_COUNT(a,b) b |
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| 67 | #else |
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| 68 | #define __ALIGNMENT_ARG |
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| 69 | #define __ALIGNMENT_COUNT(a,b) a |
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| 70 | #endif |
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| 71 | |
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| 72 | /* Provide a common macro to pass 64-bit value on syscalls. */ |
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| 73 | #if __WORDSIZE == 64 || defined __ASSUME_WORDSIZE64_ILP32 |
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| 74 | # define SYSCALL_LL(val) (val) |
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| 75 | # define SYSCALL_LL64(val) (val) |
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| 76 | #else |
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| 77 | #define SYSCALL_LL(val) \ |
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| 78 | __LONG_LONG_PAIR ((val) >> 31, (val)) |
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| 79 | #define SYSCALL_LL64(val) \ |
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| 80 | __LONG_LONG_PAIR ((long) ((val) >> 32), (long) ((val) & 0xffffffff)) |
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| 81 | #endif |
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| 82 | |
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| 83 | /* Provide a common macro to pass 64-bit value on pread and pwrite |
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| 84 | syscalls. */ |
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| 85 | #ifdef __ASSUME_PRW_DUMMY_ARG |
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| 86 | # define SYSCALL_LL_PRW(val) 0, SYSCALL_LL (val) |
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| 87 | # define SYSCALL_LL64_PRW(val) 0, SYSCALL_LL64 (val) |
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| 88 | #else |
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| 89 | # define SYSCALL_LL_PRW(val) __ALIGNMENT_ARG SYSCALL_LL (val) |
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| 90 | # define SYSCALL_LL64_PRW(val) __ALIGNMENT_ARG SYSCALL_LL64 (val) |
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| 91 | #endif |
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| 92 | |
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| 93 | /* Provide a macro to pass the off{64}_t argument on p{readv,writev}{64}. */ |
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| 94 | #define LO_HI_LONG(val) \ |
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| 95 | (long) (val), \ |
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| 96 | (long) (((uint64_t) (val)) >> 32) |
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| 97 | |
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| 98 | /* Export the ___brk_addr symbol on brk.c implementation (some ABIs export |
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| 99 | it due and old crtstuff.c code). */ |
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| 100 | #define HAVE_INTERNAL_BRK_ADDR_SYMBOL 0 |
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| 101 | |
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| 102 | #endif /* _SYSDEP_LINUX_H */ |
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| 103 | |
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