isolate tests in child processes

utest.h

@@ -33,6 +33,10 @@
 #ifndef SHEREDOM_UTEST_H_INCLUDED
 #define SHEREDOM_UTEST_H_INCLUDED
 
+#include <cstdlib>
+#include <sys/wait.h>
+#include <unistd.h>
+
 #ifdef _MSC_VER
 /*
    Disable warning about not inlining 'inline' functions.
@@ -653,7 +657,7 @@ utest_type_printer(long long unsigned int i) {
                         : _Generic((val - val), ptrdiff_t                      \
                                    : "%p", default                             \
                                    : "undef")),                                \
-               (val))
+      (val))
 #else
 /*
    we don't have the ability to print the values we got, so we create a macro
@@ -1554,21 +1558,43 @@ int utest_main(int argc, const char *const argv[]) {
 
     ns = utest_ns();
     errno = 0;
+
+    pid_t pid = fork();
+
+    if (pid == -1) {
+      perror("Fork failed");
+      exit(EXIT_FAILURE);
+    } else if (pid == 0) {
 #if defined(UTEST_HAS_EXCEPTIONS)
-    UTEST_SURPRESS_WARNING_BEGIN
-    try {
-      utest_state.tests[index].func(&result, utest_state.tests[index].index);
-    } catch (const std::exception &err) {
-      printf(" Exception : %s\n", err.what());
-      result = UTEST_TEST_FAILURE;
-    } catch (...) {
-      printf(" Exception : Unknown\n");
-      result = UTEST_TEST_FAILURE;
-    }
-    UTEST_SURPRESS_WARNING_END
+      UTEST_SURPRESS_WARNING_BEGIN
+      try {
+        utest_state.tests[index].func(&result, utest_state.tests[index].index);
+      } catch (const std::exception &err) {
+        printf(" Exception : %s\n", err.what());
+        result = UTEST_TEST_FAILURE;
+      } catch (...) {
+        printf(" Exception : Unknown\n");
+        result = UTEST_TEST_FAILURE;
+      }
+      UTEST_SURPRESS_WARNING_END
 #else
-    utest_state.tests[index].func(&result, utest_state.tests[index].index);
+      utest_state.tests[index].func(&result, utest_state.tests[index].index);
 #endif
+      exit(result);
+    } else {
+      int status;
+      waitpid(pid, &status, 0);
+      if (WIFSIGNALED(status)) {
+        result = UTEST_TEST_FAILURE;
+        printf("Test terminated due to signal %i", WTERMSIG(status));
+      } else if (WIFEXITED(status)) {
+        result = WEXITSTATUS(status);
+      } else {
+        result = UTEST_TEST_FAILURE;
+        printf("Test terminated abnormally");
+      }
+    }
+
     ns = utest_ns() - ns;
 
     if (utest_state.output) {