[llvm] 0b704d9 - [Support] Emulate SIGPIPE handling in raw_fd_ostream write for Windows
Andrew Ng via llvm-commits
llvm-commits at lists.llvm.org
Thu Feb 9 02:39:49 PST 2023
Author: Andrew Ng
Date: 2023-02-09T10:39:09Z
New Revision: 0b704d9db7e15723922ee29c6f245d108a09c214
URL: https://github.com/llvm/llvm-project/commit/0b704d9db7e15723922ee29c6f245d108a09c214
DIFF: https://github.com/llvm/llvm-project/commit/0b704d9db7e15723922ee29c6f245d108a09c214.diff
LOG: [Support] Emulate SIGPIPE handling in raw_fd_ostream write for Windows
Prevent errors and crash dumps for broken pipes on Windows.
Fixes: https://github.com/llvm/llvm-project/issues/48672
Differential Revision: https://reviews.llvm.org/D142224
Added:
Modified:
clang/lib/Driver/Driver.cpp
llvm/include/llvm/Support/ExitCodes.h
llvm/include/llvm/Support/Signals.h
llvm/lib/Support/Windows/Signals.inc
llvm/lib/Support/raw_ostream.cpp
Removed:
################################################################################
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 6c0ff3d30e643..7d43b4094b7d7 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -1873,14 +1873,12 @@ int Driver::ExecuteCompilation(
C.CleanupFileMap(C.getFailureResultFiles(), JA, true);
}
-#if LLVM_ON_UNIX
- // llvm/lib/Support/Unix/Signals.inc will exit with a special return code
+ // llvm/lib/Support/*/Signals.inc will exit with a special return code
// for SIGPIPE. Do not print diagnostics for this case.
if (CommandRes == EX_IOERR) {
Res = CommandRes;
continue;
}
-#endif
// Print extra information about abnormal failures, if possible.
//
diff --git a/llvm/include/llvm/Support/ExitCodes.h b/llvm/include/llvm/Support/ExitCodes.h
index b9041f5557d52..4eb5dedc688bc 100644
--- a/llvm/include/llvm/Support/ExitCodes.h
+++ b/llvm/include/llvm/Support/ExitCodes.h
@@ -20,9 +20,9 @@
#if HAVE_SYSEXITS_H
#include <sysexits.h>
-#elif __MVS__
-// <sysexits.h> does not exist on z/OS. The only value used in LLVM is
-// EX_IOERR, which is used to signal a special error condition (broken pipe).
+#elif __MVS__ || defined(_WIN32)
+// <sysexits.h> does not exist on z/OS and Windows. The only value used in LLVM
+// is EX_IOERR, which is used to signal a special error condition (broken pipe).
// Define the macro with its usual value from BSD systems, which is chosen to
// not clash with more standard exit codes like 1.
#define EX_IOERR 74
diff --git a/llvm/include/llvm/Support/Signals.h b/llvm/include/llvm/Support/Signals.h
index 937e0572d4a72..70749ce30184a 100644
--- a/llvm/include/llvm/Support/Signals.h
+++ b/llvm/include/llvm/Support/Signals.h
@@ -102,14 +102,17 @@ namespace sys {
/// functions. A null handler pointer disables the current installed
/// function. Note also that the handler may be executed on a
///
diff erent thread on some platforms.
- ///
- /// This is a no-op on Windows.
void SetOneShotPipeSignalFunction(void (*Handler)());
- /// On Unix systems, this function exits with an "IO error" exit code.
- /// This is a no-op on Windows.
+ /// On Unix systems and Windows, this function exits with an "IO error" exit
+ /// code.
void DefaultOneShotPipeSignalHandler();
+#ifdef _WIN32
+ /// Windows does not support signals and this handler must be called manually.
+ void CallOneShotPipeSignalHandler();
+#endif
+
/// This function does the following:
/// - clean up any temporary files registered with RemoveFileOnSignal()
/// - dump the callstack from the exception context
diff --git a/llvm/lib/Support/Windows/Signals.inc b/llvm/lib/Support/Windows/Signals.inc
index ba93afe0803b4..4bf699f2bccf0 100644
--- a/llvm/lib/Support/Windows/Signals.inc
+++ b/llvm/lib/Support/Windows/Signals.inc
@@ -10,6 +10,7 @@
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/ConvertUTF.h"
+#include "llvm/Support/ExitCodes.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/Process.h"
@@ -204,6 +205,9 @@ static bool RegisteredUnhandledExceptionFilter = false;
static bool CleanupExecuted = false;
static PTOP_LEVEL_EXCEPTION_FILTER OldFilter = NULL;
+/// The function to call on "SIGPIPE" (one-time use only).
+static std::atomic<void (*)()> OneShotPipeSignalFunction(nullptr);
+
// Windows creates a new thread to execute the console handler when an event
// (such as CTRL/C) occurs. This causes concurrency issues with the above
// globals which this critical section addresses.
@@ -575,11 +579,16 @@ void llvm::sys::SetInfoSignalFunction(void (*Handler)()) {
}
void llvm::sys::SetOneShotPipeSignalFunction(void (*Handler)()) {
- // Unimplemented.
+ OneShotPipeSignalFunction.exchange(Handler);
}
void llvm::sys::DefaultOneShotPipeSignalHandler() {
- // Unimplemented.
+ llvm::sys::Process::Exit(EX_IOERR, /*NoCleanup=*/true);
+}
+
+void llvm::sys::CallOneShotPipeSignalHandler() {
+ if (auto OldOneShotPipeFunction = OneShotPipeSignalFunction.exchange(nullptr))
+ OldOneShotPipeFunction();
}
/// Add a function to be called when a signal is delivered to the process. The
@@ -816,7 +825,15 @@ WriteWindowsDumpFile(PMINIDUMP_EXCEPTION_INFORMATION ExceptionInfo) {
}
void sys::CleanupOnSignal(uintptr_t Context) {
- LLVMUnhandledExceptionFilter((LPEXCEPTION_POINTERS)Context);
+ LPEXCEPTION_POINTERS EP = (LPEXCEPTION_POINTERS)Context;
+ // Broken pipe is not a crash.
+ //
+ // 0xE0000000 is combined with the return code in the exception raised in
+ // CrashRecoveryContext::HandleExit().
+ int RetCode = (int)EP->ExceptionRecord->ExceptionCode;
+ if (RetCode == (0xE0000000 | EX_IOERR))
+ return;
+ LLVMUnhandledExceptionFilter(EP);
}
static LONG WINAPI LLVMUnhandledExceptionFilter(LPEXCEPTION_POINTERS ep) {
diff --git a/llvm/lib/Support/raw_ostream.cpp b/llvm/lib/Support/raw_ostream.cpp
index 8943c4478c7f2..7b9b8b2f53fba 100644
--- a/llvm/lib/Support/raw_ostream.cpp
+++ b/llvm/lib/Support/raw_ostream.cpp
@@ -56,6 +56,7 @@
#ifdef _WIN32
#include "llvm/Support/ConvertUTF.h"
+#include "llvm/Support/Signals.h"
#include "llvm/Support/Windows/WindowsSupport.h"
#endif
@@ -775,6 +776,15 @@ void raw_fd_ostream::write_impl(const char *Ptr, size_t Size) {
)
continue;
+#ifdef _WIN32
+ // Windows equivalents of SIGPIPE/EPIPE.
+ DWORD WinLastError = GetLastError();
+ if (WinLastError == ERROR_BROKEN_PIPE ||
+ (WinLastError == ERROR_NO_DATA && errno == EINVAL)) {
+ llvm::sys::CallOneShotPipeSignalHandler();
+ errno = EPIPE;
+ }
+#endif
// Otherwise it's a non-recoverable error. Note it and quit.
error_detected(std::error_code(errno, std::generic_category()));
break;
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