SERVER-48696 sigaction actions need to all be extern "C"

6 files changed, 63 insertions, 36 deletions

diff --git a/src/mongo/shell/mongo_main.cpp b/src/mongo/shell/mongo_main.cpp
index 4a4069077f7..6d0ff876265 100644
--- a/src/mongo/shell/mongo_main.cpp
+++ b/src/mongo/shell/mongo_main.cpp
@@ -304,7 +304,7 @@ void killOps() {
         !shellGlobalParams.autoKillOp);
 }
 
-void quitNicely(int sig) {
+extern "C" void quitNicely(int sig) {
     shutdown(EXIT_CLEAN);
 }
 
diff --git a/src/mongo/stdx/sigaltstack_location_test.cpp b/src/mongo/stdx/sigaltstack_location_test.cpp
index bfc0aba4393..e2d1d59fd36 100644
--- a/src/mongo/stdx/sigaltstack_location_test.cpp
+++ b/src/mongo/stdx/sigaltstack_location_test.cpp
@@ -69,8 +69,10 @@ void unblockSignal(int sig) {
     }
 }
 
+extern "C" typedef void(sigAction_t)(int signum, siginfo_t* info, void* context);
+
 /** Install action for signal sig. Be careful to specify SA_ONSTACK. */
-void installAction(int sig, void (*action)(int, siginfo_t*, void*)) {
+void installAction(int sig, sigAction_t* action) {
     struct sigaction sa;
     sa.sa_sigaction = action;
     sa.sa_flags = SA_SIGINFO | SA_ONSTACK;
@@ -100,39 +102,42 @@ struct Hex {
     const T& _t;
 };
 
+struct StackLocationTestChildThreadInfo {
+    stack_t ss;
+    const char* handlerLocal;
+};
+static StackLocationTestChildThreadInfo stackLocationTestChildInfo{};
+
+extern "C" void stackLocationTestAction(int, siginfo_t*, void*) {
+    char n;
+    stackLocationTestChildInfo.handlerLocal = &n;
+}
+
 int stackLocationTest() {
-    struct ChildThreadInfo {
-        stack_t ss;
-        const char* handlerLocal;
-    };
-    static ChildThreadInfo childInfo{};
 
     stdx::thread childThread([&] {
         static const int kSignal = SIGUSR1;
         // Use sigaltstack's `old_ss` parameter to query the installed sigaltstack.
-        if (sigaltstack(nullptr, &childInfo.ss)) {
+        if (sigaltstack(nullptr, &stackLocationTestChildInfo.ss)) {
             perror("sigaltstack");
             abort();
         }
         unblockSignal(kSignal);
-        installAction(kSignal, [](int, siginfo_t*, void*) {
-            char n;
-            childInfo.handlerLocal = &n;
-        });
+        installAction(kSignal, &stackLocationTestAction);
         // `raise` waits for signal handler to complete.
         // https://pubs.opengroup.org/onlinepubs/009695399/functions/raise.html
         raise(kSignal);
     });
     childThread.join();
 
-    if (childInfo.ss.ss_flags & SS_DISABLE) {
+    if (stackLocationTestChildInfo.ss.ss_flags & SS_DISABLE) {
         std::cerr << "Child thread unexpectedly had sigaltstack disabled." << std::endl;
         exit(EXIT_FAILURE);
     }
 
-    uintptr_t altStackBegin = reinterpret_cast<uintptr_t>(childInfo.ss.ss_sp);
-    uintptr_t altStackEnd = altStackBegin + childInfo.ss.ss_size;
-    uintptr_t handlerLocal = reinterpret_cast<uintptr_t>(childInfo.handlerLocal);
+    uintptr_t altStackBegin = reinterpret_cast<uintptr_t>(stackLocationTestChildInfo.ss.ss_sp);
+    uintptr_t altStackEnd = altStackBegin + stackLocationTestChildInfo.ss.ss_size;
+    uintptr_t handlerLocal = reinterpret_cast<uintptr_t>(stackLocationTestChildInfo.handlerLocal);
 
     std::cerr << "child sigaltstack[" << Hex(altStackEnd - altStackBegin) << "] = ["
               << Hex(altStackBegin) << ", " << Hex(altStackEnd) << ")\n"
@@ -146,6 +151,12 @@ int stackLocationTest() {
     return EXIT_SUCCESS;
 }
 
+static sigjmp_buf sigjmp;
+
+extern "C" void siglongjmpAction(int, siginfo_t*, void*) {
+    siglongjmp(sigjmp, 1);
+}
+
 /**
  * Start a child thread which overflows its stack, causing it to receive a SIGSEGV.  If
  * !useSigAltStack, disable that child thread's sigaltstack.
@@ -160,10 +171,9 @@ int stackLocationTest() {
  * SIGSEGV is process-fatal.
  */
 int recursionTestImpl(bool useSigAltStack) {
-    static sigjmp_buf sigjmp;
 
     unblockSignal(SIGSEGV);
-    installAction(SIGSEGV, [](int, siginfo_t*, void*) { siglongjmp(sigjmp, 1); });
+    installAction(SIGSEGV, siglongjmpAction);
 
     stdx::thread childThread([=] {
         if (!useSigAltStack) {
diff --git a/src/mongo/util/debugger.cpp b/src/mongo/util/debugger.cpp
index c4a89d0bdc2..3bd216f1656 100644
--- a/src/mongo/util/debugger.cpp
+++ b/src/mongo/util/debugger.cpp
@@ -117,7 +117,7 @@ void launchDebugger(Exec debugger) {
 
 #if defined(USE_GDBSERVER)
 
-void execCallback(int) {
+extern "C" void execCallback(int) {
     launchDebugger([](char* pidToDebug) {
         execlp("gdbserver", "gdbserver", "--attach", ":0", pidToDebug, nullptr);
     });
@@ -125,7 +125,7 @@ void execCallback(int) {
 
 #elif defined(USE_LLDB_SERVER)
 
-void execCallback(int) {
+extern "C" void execCallback(int) {
     launchDebugger([](char* pidToDebug) {
 #ifdef __linux__
         execlp("lldb-server", "lldb-server", "g", "--attach", pidToDebug, "*:12345", nullptr);
diff --git a/src/mongo/util/signal_handlers_synchronous.cpp b/src/mongo/util/signal_handlers_synchronous.cpp
index 7a1d2261bee..dbb2caacb4f 100644
--- a/src/mongo/util/signal_handlers_synchronous.cpp
+++ b/src/mongo/util/signal_handlers_synchronous.cpp
@@ -257,7 +257,7 @@ void myTerminate() {
     endProcessWithSignal(SIGABRT);
 }
 
-void abruptQuit(int signalNum) {
+extern "C" void abruptQuit(int signalNum) {
     MallocFreeOStreamGuard lk{};
     printSignalAndBacktrace(signalNum);
     breakpoint();
@@ -292,11 +292,11 @@ void myPureCallHandler() {
 
 #else
 
-void abruptQuitAction(int signalNum, siginfo_t*, void*) {
+extern "C" void abruptQuitAction(int signalNum, siginfo_t*, void*) {
     abruptQuit(signalNum);
 };
 
-void abruptQuitWithAddrSignal(int signalNum, siginfo_t* siginfo, void* ucontext_erased) {
+extern "C" void abruptQuitWithAddrSignal(int signalNum, siginfo_t* siginfo, void* ucontext_erased) {
     // For convenient debugger access.
     MONGO_COMPILER_VARIABLE_UNUSED auto ucontext = static_cast<const ucontext_t*>(ucontext_erased);
 
@@ -319,6 +319,10 @@ void abruptQuitWithAddrSignal(int signalNum, siginfo_t* siginfo, void* ucontext_
 
 }  // namespace
 
+#if !defined(_WIN32)
+extern "C" typedef void(sigAction_t)(int signum, siginfo_t* info, void* context);
+#endif
+
 void setupSynchronousSignalHandlers() {
     stdx::set_terminate(myTerminate);
     std::set_new_handler(reportOutOfMemoryErrorAndExit);
@@ -331,7 +335,7 @@ void setupSynchronousSignalHandlers() {
 #else
     static constexpr struct {
         int signal;
-        void (*function)(int, siginfo_t*, void*);  // signal ignored if nullptr
+        sigAction_t* function;  // signal ignored if nullptr
     } kSignalSpecs[] = {
         {SIGHUP, nullptr},
         {SIGUSR2, nullptr},
diff --git a/src/mongo/util/stacktrace_test.cpp b/src/mongo/util/stacktrace_test.cpp
index 9bf6dd99a19..cb06e5e8ef8 100644
--- a/src/mongo/util/stacktrace_test.cpp
+++ b/src/mongo/util/stacktrace_test.cpp
@@ -377,6 +377,8 @@ TEST(StackTrace, MetadataGeneratorFunctionMeasure) {
 #endif  // _WIN32
 
 #ifdef HAVE_SIGALTSTACK
+extern "C" typedef void(sigAction_t)(int signum, siginfo_t* info, void* context);
+
 class StackTraceSigAltStackTest : public unittest::Test {
 public:
     using unittest::Test::Test;
@@ -398,7 +400,7 @@ public:
             23388, "Local var", "var"_attr = "{:X}"_format(reinterpret_cast<uintptr_t>(&storage)));
     }
 
-    static void tryHandler(void (*handler)(int, siginfo_t*, void*)) {
+    static void tryHandler(sigAction_t* handler) {
         constexpr int sig = SIGUSR1;
         constexpr size_t kStackSize = size_t{1} << 20;  // 1 MiB
         auto buf = std::make_unique<std::array<unsigned char, kStackSize>>();
@@ -447,23 +449,31 @@ public:
     }
 };
 
+extern "C" void stackTraceSigAltStackMinimalAction(int sig, siginfo_t*, void*) {
+    StackTraceSigAltStackTest::handlerPreamble(sig);
+}
+
 TEST_F(StackTraceSigAltStackTest, Minimal) {
-    tryHandler([](int sig, siginfo_t*, void*) { handlerPreamble(sig); });
+    StackTraceSigAltStackTest::tryHandler(stackTraceSigAltStackMinimalAction);
+}
+
+extern "C" void stackTraceSigAltStackPrintAction(int sig, siginfo_t*, void*) {
+    StackTraceSigAltStackTest::handlerPreamble(sig);
+    printStackTrace();
 }
 
 TEST_F(StackTraceSigAltStackTest, Print) {
-    tryHandler([](int sig, siginfo_t*, void*) {
-        handlerPreamble(sig);
-        printStackTrace();
-    });
+    StackTraceSigAltStackTest::tryHandler(&stackTraceSigAltStackPrintAction);
+}
+
+extern "C" void stackTraceSigAltStackBacktraceAction(int sig, siginfo_t*, void*) {
+    StackTraceSigAltStackTest::handlerPreamble(sig);
+    std::array<void*, kStackTraceFrameMax> addrs;
+    rawBacktrace(addrs.data(), addrs.size());
 }
 
 TEST_F(StackTraceSigAltStackTest, Backtrace) {
-    tryHandler([](int sig, siginfo_t*, void*) {
-        handlerPreamble(sig);
-        std::array<void*, kStackTraceFrameMax> addrs;
-        rawBacktrace(addrs.data(), addrs.size());
-    });
+    StackTraceSigAltStackTest::tryHandler(stackTraceSigAltStackBacktraceAction);
 }
 #endif  // HAVE_SIGALTSTACK
 
diff --git a/src/mongo/util/stacktrace_threads.cpp b/src/mongo/util/stacktrace_threads.cpp
index 62a5b020a2c..d2ee29d24b4 100644
--- a/src/mongo/util/stacktrace_threads.cpp
+++ b/src/mongo/util/stacktrace_threads.cpp
@@ -638,6 +638,9 @@ void State::action(siginfo_t* si) {
 }
 
 State* stateSingleton = new State{};
+extern "C" void stateSingletonAction(int, siginfo_t* si, void*) {
+    stateSingleton->action(si);
+}
 
 /**
  * Called from single-thread init time. The stack tracer will use the specified `signal`.
@@ -650,7 +653,7 @@ void initialize(int signal) {
     // We should never need to add to this lambda because it simply sets up handler
     // execution. Any changes should either be in State::action or in the signal
     // handler itself.
-    sa.sa_sigaction = [](int, siginfo_t* si, void*) { stateSingleton->action(si); };
+    sa.sa_sigaction = stateSingletonAction;
     sa.sa_flags = SA_SIGINFO | SA_ONSTACK | SA_RESTART;
     if (sigaction(signal, &sa, nullptr) != 0) {
         int savedErr = errno;