[libc] add proxy header for struct_sigaction

[SchrodingerZhu]

Split from #91572

[llvmbot]

@llvm/pr-subscribers-libc

Author: Schrodinger ZHU Yifan (SchrodingerZhu)

Changes

Split from #91572

---

Full diff: https://github.com/llvm/llvm-project/pull/96224.diff

4 Files Affected:

• (modified) libc/hdr/types/CMakeLists.txt (+9)
• (added) libc/hdr/types/struct_sigaction.h (+21)
• (modified) libc/src/signal/linux/CMakeLists.txt (+1)
• (modified) libc/src/signal/sigaction.h (+1-1)

diff --git a/libc/hdr/types/CMakeLists.txt b/libc/hdr/types/CMakeLists.txt
index 9b3373a0ca390..1cab1d3b812cf 100644
--- a/libc/hdr/types/CMakeLists.txt
+++ b/libc/hdr/types/CMakeLists.txt
@@ -126,3 +126,12 @@ add_proxy_header_library(
     libc.include.llvm-libc-types.atexithandler_t
     libc.include.stdlib
 )
+
+add_proxy_header_library(
+  struct_sigaction
+  HDRS
+    struct_sigaction.h
+  FULL_BUILD_DEPENDS
+    libc.include.llvm-libc-types.struct_sigaction
+    libc.include.signal
+)
diff --git a/libc/hdr/types/struct_sigaction.h b/libc/hdr/types/struct_sigaction.h
new file mode 100644
index 0000000000000..60f6caeb4af10
--- /dev/null
+++ b/libc/hdr/types/struct_sigaction.h
@@ -0,0 +1,21 @@
+//===-- Proxy for struct sigaction  ---------------------------------------===//
+//
+// 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_HDR_TYPES_STRUCT_SIGACTION_H
+#define LLVM_LIBC_HDR_TYPES_STRUCT_SIGACTION_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-types/struct_sigaction.h"
+
+#else
+
+#include <signal.h>
+
+#endif // LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_TYPES_STRUCT_SIGACTION_H
diff --git a/libc/src/signal/linux/CMakeLists.txt b/libc/src/signal/linux/CMakeLists.txt
index 7606b4b21d3dd..b03d06a0bc4c7 100644
--- a/libc/src/signal/linux/CMakeLists.txt
+++ b/libc/src/signal/linux/CMakeLists.txt
@@ -60,6 +60,7 @@ add_entrypoint_object(
   DEPENDS
     .__restore
     libc.hdr.types.sigset_t
+    libc.hdr.types.struct_sigaction
     libc.include.sys_syscall
     libc.src.__support.OSUtil.osutil
     libc.src.errno.errno
diff --git a/libc/src/signal/sigaction.h b/libc/src/signal/sigaction.h
index c36a3ec9fedfa..293093f6a0751 100644
--- a/libc/src/signal/sigaction.h
+++ b/libc/src/signal/sigaction.h
@@ -9,7 +9,7 @@
 #ifndef LLVM_LIBC_SRC_SIGNAL_SIGACTION_H
 #define LLVM_LIBC_SRC_SIGNAL_SIGACTION_H
 
-#include <signal.h>
+#include <hdr/types/struct_sigaction.h>
 
 namespace LIBC_NAMESPACE {
 

[michaelrj-google]

LGTM after one change

[nickdesaulniers]

Can we clean up test/src/signal/sigaltstack_test.cpp with this change?

and test/src/signal/sigaction_test.cpp
src/signal/linux/signal.cpp

[nickdesaulniers]

Why do we need libc.include.signal?

[SchrodingerZhu]

I think it is a convention in proxy headers to require the full build to generate the outer-level header. This is employed in all other proxy type headers. @lntue

[nickdesaulniers]

Approving for now, but perhaps worth revisiting this convention. @lntue ?

[SchrodingerZhu]

merge this for now. if the convention is revised, we should better revisit all other files.