| //===-- Linux implementation of sigaltstack -------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "src/signal/sigaltstack.h" |
| #include "src/errno/libc_errno.h" |
| #include "src/signal/linux/signal_utils.h" |
| |
| #include "src/__support/common.h" |
| |
| #include <signal.h> |
| #include <sys/syscall.h> |
| |
| namespace __llvm_libc { |
| |
| LLVM_LIBC_FUNCTION(int, sigaltstack, |
| (const stack_t *__restrict ss, stack_t *__restrict oss)) { |
| if (ss != nullptr) { |
| unsigned not_ss_disable = ~unsigned(SS_DISABLE); |
| if ((unsigned(ss->ss_flags) & not_ss_disable) != 0) { |
| // Flags cannot have anything other than SS_DISABLE set. |
| // We do the type-casting to unsigned because the |ss_flags| |
| // field of stack_t is of type "int". |
| libc_errno = EINVAL; |
| return -1; |
| } |
| if (ss->ss_size < MINSIGSTKSZ) { |
| libc_errno = ENOMEM; |
| return -1; |
| } |
| } |
| |
| int ret = __llvm_libc::syscall_impl(SYS_sigaltstack, ss, oss); |
| if (ret < 0) { |
| libc_errno = -ret; |
| return -1; |
| } |
| return 0; |
| } |
| |
| } // namespace __llvm_libc |