Merge pull request #5273 from Sonicadvance1/70

unittests/FEXLinuxTests: Ensures that signals are in expected order

unittests/FEXLinuxTests/tests/signal/signal_order.cpp

@@ -0,0 +1,105 @@
+#include <catch2/catch_test_macros.hpp>
+#include <unistd.h>
+#include <signal.h>
+#include <sys/syscall.h>
+#include <stdio.h>
+
+constexpr uint64_t ExpectedOrder[64] = {
+  0,  1,  2,  3,  4,  5,  6,  7,  0,  8,  9,  10, 11, 12, 13, 14, 15, 16, 0,  17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
+  30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
+};
+
+uint64_t Count {};
+uint64_t Order[64] = {};
+
+#ifndef __x86_64__
+[[gnu::regparm(3)]]
+#endif
+static void handler(int signal, siginfo_t* siginfo, void* context) {
+  REQUIRE((signal > 0 && signal < 65));
+  if (signal < 1 || signal > 64) {
+    return;
+  }
+  Order[signal - 1] = Count;
+  ++Count;
+}
+
+#ifdef __x86_64__
+__attribute__((naked)) void asm_handler(int signal, siginfo_t* siginfo, void* context) {
+  __asm volatile(R"(
+  call %[Handler];
+  ret;
+  )" ::[Handler] "r"(handler)
+                 : "memory");
+}
+
+__attribute__((naked)) void restorer() {
+  __asm volatile(R"(
+  mov eax, %[sigreturn];
+  syscall;
+  )" ::[sigreturn] "i"(SYS_rt_sigreturn)
+                 : "memory");
+}
+#else
+__attribute__((naked)) void asm_handler(int signal, siginfo_t* siginfo, void* context) {
+  __asm volatile(R"(
+  mov ebx, %[Handler];
+  mov eax, [esp + 4];
+  mov ecx, [esp + 8];
+  mov edx, [esp + 12];
+  call ebx;
+  ret;
+  )" ::[Handler] "r"(handler)
+                 : "eax", "ecx", "edx", "memory");
+}
+
+
+__attribute__((naked)) void restorer() {
+  __asm volatile(R"(
+  mov eax, %[sigreturn];
+  int 0x80;
+  )" ::[sigreturn] "i"(SYS_rt_sigreturn)
+                 : "memory");
+}
+#endif
+
+
+struct __attribute__((packed)) GuestSAMask {
+  uint64_t Val;
+};
+
+struct __attribute__((packed)) GuestSigAction {
+  union {
+    void (*handler)(int);
+    void (*sigaction)(int, siginfo_t*, void*);
+  } sigaction_handler;
+
+  size_t sa_flags;
+  void (*restorer)(void);
+  GuestSAMask sa_mask;
+};
+
+TEST_CASE("signal order") {
+
+#define SA_RESTORER 0x04000000
+  struct GuestSigAction act {};
+  act.sigaction_handler.sigaction = (decltype(act.sigaction_handler.sigaction))asm_handler;
+  act.restorer = restorer;
+  act.sa_flags = SA_SIGINFO | SA_RESTORER;
+  for (size_t i = 1; i <= 64; ++i) {
+    ::syscall(SYS_rt_sigaction, i, &act, nullptr, 8);
+  }
+
+  auto pid = ::getpid();
+  auto tid = ::gettid();
+  for (size_t i = 1; i <= 64; ++i) {
+    if (i == SIGKILL || i == SIGSTOP) {
+      continue;
+    }
+    tgkill(pid, tid, i);
+  }
+
+  for (size_t i = 1; i <= 64; ++i) {
+    CHECK(Order[i - 1] == ExpectedOrder[i - 1]);
+  }
+}