[libc-commits] [libc] [libc][syscall] lift raise to syscall wrapper (PR #189507)
Schrodinger ZHU Yifan via libc-commits
libc-commits at lists.llvm.org
Mon Mar 30 17:55:42 PDT 2026
https://github.com/SchrodingerZhu updated https://github.com/llvm/llvm-project/pull/189507
>From e964500f717fee5ab76de4399c6565cf1013039d Mon Sep 17 00:00:00 2001
From: Schrodinger ZHU Yifan <i at zhuyi.fan>
Date: Mon, 30 Mar 2026 19:44:48 -0400
Subject: [PATCH 1/2] [libc][syscall] lift raise to syscall wrapper
---
.../linux/syscall_wrappers/CMakeLists.txt | 14 ++++
.../OSUtil/linux/syscall_wrappers/raise.h | 64 +++++++++++++++++++
libc/src/signal/linux/CMakeLists.txt | 6 +-
libc/src/signal/linux/raise.cpp | 17 +++--
4 files changed, 88 insertions(+), 13 deletions(-)
create mode 100644 libc/src/__support/OSUtil/linux/syscall_wrappers/raise.h
diff --git a/libc/src/__support/OSUtil/linux/syscall_wrappers/CMakeLists.txt b/libc/src/__support/OSUtil/linux/syscall_wrappers/CMakeLists.txt
index d5f552f7b6c46..50e31eba161d6 100644
--- a/libc/src/__support/OSUtil/linux/syscall_wrappers/CMakeLists.txt
+++ b/libc/src/__support/OSUtil/linux/syscall_wrappers/CMakeLists.txt
@@ -36,6 +36,20 @@ add_header_library(
libc.include.sys_syscall
)
+add_header_library(
+ raise
+ HDRS
+ raise.h
+ DEPENDS
+ libc.src.__support.OSUtil.osutil
+ libc.src.__support.common
+ libc.src.__support.error_or
+ libc.src.__support.macros.config
+ libc.hdr.signal_macros
+ libc.hdr.types.sigset_t
+ libc.include.sys_syscall
+)
+
add_header_library(
write
HDRS
diff --git a/libc/src/__support/OSUtil/linux/syscall_wrappers/raise.h b/libc/src/__support/OSUtil/linux/syscall_wrappers/raise.h
new file mode 100644
index 0000000000000..bad2ac4214844
--- /dev/null
+++ b/libc/src/__support/OSUtil/linux/syscall_wrappers/raise.h
@@ -0,0 +1,64 @@
+//===-- Implementation header for raise -------------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_SYSCALL_WRAPPERS_RAISE_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_SYSCALL_WRAPPERS_RAISE_H
+
+#include "hdr/signal_macros.h"
+#include "hdr/types/sigset_t.h"
+#include "src/__support/OSUtil/linux/syscall.h" // syscall_impl
+#include "src/__support/common.h"
+#include "src/__support/error_or.h"
+#include "src/__support/macros/config.h"
+#include <sys/syscall.h> // For syscall numbers
+
+namespace LIBC_NAMESPACE_DECL {
+namespace linux_syscalls {
+
+LIBC_INLINE ErrorOr<int> raise(int sig) {
+ sigset_t full_set = sigset_t{{-1UL}};
+#ifdef LIBC_COMPILER_IS_CLANG
+ [[clang::uninitialized]] sigset_t old_set;
+#else
+ sigset_t old_set;
+#endif
+ auto restore_signals = [&old_set]() {
+ return syscall_impl<int>(SYS_rt_sigprocmask, SIG_SETMASK, &old_set, nullptr,
+ sizeof(sigset_t));
+ };
+
+ int mask_result = syscall_impl<int>(SYS_rt_sigprocmask, SIG_BLOCK, &full_set,
+ &old_set, sizeof(sigset_t));
+ if (mask_result < 0)
+ return Error(-mask_result);
+
+ long pid = syscall_impl<long>(SYS_getpid);
+ if (pid < 0) {
+ restore_signals();
+ return Error(-static_cast<int>(pid));
+ }
+
+ long tid = syscall_impl<long>(SYS_gettid);
+ if (tid < 0) {
+ restore_signals();
+ return Error(-static_cast<int>(tid));
+ }
+
+ int result = syscall_impl<int>(SYS_tgkill, pid, tid, sig);
+ int restore_result = restore_signals();
+ if (result < 0)
+ return Error(-result);
+ if (restore_result < 0)
+ return Error(-restore_result);
+ return result;
+}
+
+} // namespace linux_syscalls
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_SYSCALL_WRAPPERS_RAISE_H
diff --git a/libc/src/signal/linux/CMakeLists.txt b/libc/src/signal/linux/CMakeLists.txt
index c0dd61e473881..c8a7d95a4f22d 100644
--- a/libc/src/signal/linux/CMakeLists.txt
+++ b/libc/src/signal/linux/CMakeLists.txt
@@ -29,10 +29,8 @@ add_entrypoint_object(
HDRS
../raise.h
DEPENDS
- .signal_utils
- libc.hdr.types.sigset_t
- libc.include.sys_syscall
- libc.src.__support.OSUtil.osutil
+ libc.src.__support.OSUtil.linux.syscall_wrappers.raise
+ libc.src.errno.errno
)
add_object_library(
diff --git a/libc/src/signal/linux/raise.cpp b/libc/src/signal/linux/raise.cpp
index 4a8913941db11..9425e95e46d00 100644
--- a/libc/src/signal/linux/raise.cpp
+++ b/libc/src/signal/linux/raise.cpp
@@ -8,21 +8,20 @@
#include "src/signal/raise.h"
-#include "hdr/types/sigset_t.h"
+#include "src/__support/OSUtil/linux/syscall_wrappers/raise.h"
#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
#include "src/__support/macros/config.h"
-#include "src/signal/linux/signal_utils.h"
namespace LIBC_NAMESPACE_DECL {
LLVM_LIBC_FUNCTION(int, raise, (int sig)) {
- sigset_t sigset;
- block_all_signals(sigset);
- long pid = LIBC_NAMESPACE::syscall_impl<long>(SYS_getpid);
- long tid = LIBC_NAMESPACE::syscall_impl<long>(SYS_gettid);
- int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_tgkill, pid, tid, sig);
- restore_signals(sigset);
- return ret;
+ auto result = linux_syscalls::raise(sig);
+ if (!result.has_value()) {
+ libc_errno = result.error();
+ return -1;
+ }
+ return result.value();
}
} // namespace LIBC_NAMESPACE_DECL
>From 61251bd13b1c6a2881444c66be54aef77d9b639e Mon Sep 17 00:00:00 2001
From: Schrodinger ZHU Yifan <i at zhuyi.fan>
Date: Mon, 30 Mar 2026 20:55:29 -0400
Subject: [PATCH 2/2] RAII style
---
.../OSUtil/linux/syscall_wrappers/raise.h | 66 ++++++++++---------
1 file changed, 35 insertions(+), 31 deletions(-)
diff --git a/libc/src/__support/OSUtil/linux/syscall_wrappers/raise.h b/libc/src/__support/OSUtil/linux/syscall_wrappers/raise.h
index bad2ac4214844..33d0ade124daa 100644
--- a/libc/src/__support/OSUtil/linux/syscall_wrappers/raise.h
+++ b/libc/src/__support/OSUtil/linux/syscall_wrappers/raise.h
@@ -19,43 +19,47 @@
namespace LIBC_NAMESPACE_DECL {
namespace linux_syscalls {
-
LIBC_INLINE ErrorOr<int> raise(int sig) {
- sigset_t full_set = sigset_t{{-1UL}};
-#ifdef LIBC_COMPILER_IS_CLANG
- [[clang::uninitialized]] sigset_t old_set;
-#else
- sigset_t old_set;
-#endif
- auto restore_signals = [&old_set]() {
- return syscall_impl<int>(SYS_rt_sigprocmask, SIG_SETMASK, &old_set, nullptr,
- sizeof(sigset_t));
+ class SigMaskGuard {
+ [[maybe_unused]] sigset_t old_set;
+ [[maybe_unused]] ErrorOr<int> &status;
+
+ public:
+ LIBC_INLINE SigMaskGuard(ErrorOr<int> &status) : old_set{}, status(status) {
+ sigset_t full_set = sigset_t{{-1UL}};
+ status = syscall_impl<int>(SYS_rt_sigprocmask, SIG_BLOCK, &full_set,
+ &old_set, sizeof(sigset_t));
+ }
+ LIBC_INLINE ~SigMaskGuard() {
+ if (status.has_value()) {
+ int restore_result =
+ syscall_impl<int>(SYS_rt_sigprocmask, SIG_SETMASK, &old_set,
+ nullptr, sizeof(sigset_t));
+ if (restore_result < 0)
+ status = Error(-restore_result);
+ }
+ }
};
+ ErrorOr<int> status = 0;
+ {
+ SigMaskGuard sig_mask(status);
- int mask_result = syscall_impl<int>(SYS_rt_sigprocmask, SIG_BLOCK, &full_set,
- &old_set, sizeof(sigset_t));
- if (mask_result < 0)
- return Error(-mask_result);
+ if (!status.has_value())
+ return status;
- long pid = syscall_impl<long>(SYS_getpid);
- if (pid < 0) {
- restore_signals();
- return Error(-static_cast<int>(pid));
- }
+ long pid = syscall_impl<long>(SYS_getpid);
+ if (pid < 0)
+ return Error(-static_cast<int>(pid));
- long tid = syscall_impl<long>(SYS_gettid);
- if (tid < 0) {
- restore_signals();
- return Error(-static_cast<int>(tid));
- }
+ long tid = syscall_impl<long>(SYS_gettid);
+ if (tid < 0)
+ return Error(-static_cast<int>(tid));
- int result = syscall_impl<int>(SYS_tgkill, pid, tid, sig);
- int restore_result = restore_signals();
- if (result < 0)
- return Error(-result);
- if (restore_result < 0)
- return Error(-restore_result);
- return result;
+ int result = syscall_impl<int>(SYS_tgkill, pid, tid, sig);
+ if (result < 0)
+ return Error(-result);
+ }
+ return status;
}
} // namespace linux_syscalls
More information about the libc-commits
mailing list