1 //===-- Linux implementation of syscall -----------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "src/unistd/syscall.h" 10 11 #include "src/__support/OSUtil/syscall.h" // For internal syscall function. 12 #include "src/__support/common.h" 13 14 #include "src/errno/libc_errno.h" 15 #include <stdarg.h> 16 17 namespace LIBC_NAMESPACE { 18 19 LLVM_LIBC_FUNCTION(long, __llvm_libc_syscall, 20 (long number, long arg1, long arg2, long arg3, long arg4, 21 long arg5, long arg6)) { 22 long ret = LIBC_NAMESPACE::syscall_impl<long>(number, arg1, arg2, arg3, arg4, 23 arg5, arg6); 24 // Syscalls may return large positive values that overflow, but will never 25 // return values between -4096 and -1 26 if (static_cast<unsigned long>(ret) > -4096UL) { 27 libc_errno = static_cast<int>(-ret); 28 return -1; 29 } 30 return ret; 31 } 32 33 } // namespace LIBC_NAMESPACE 34