Steve Hay's patch to detect fork capabilities

Patch is 79f8362,
I slightly reworked it to include the fork detection
code in Win32::API::Test, which seemed appropriate to me.

Callback/t/iat.t

@@ -88,14 +88,18 @@ is($patch->GetOriginalFunctionPtr(),
 
 SKIP: {
     Win32::API::Type->typedef('PRTL_PROCESS_MODULES', 'char *');
+
     my $LdrQueryProcessModuleInformation =
     Win32::API::More->new("ntdll.dll",
     "NTSTATUS NTAPI  LdrQueryProcessModuleInformation(".
     "PRTL_PROCESS_MODULES ModuleInformation,
     ULONG Size, PULONG ReturnedSize)");
-    skip("This Perl doesn't have ithreads and/or this Windows OS doesn't have "
-         ."LdrQueryProcessModuleInformation", 6) if ! $Config{'useithreads'}
-    || ! $LdrQueryProcessModuleInformation; #Native API changed, thats ok
+
+    skip("This Perl doesn't have fork and/or this Windows OS "
+        . " doesn't have LdrQueryProcessModuleInformation", 6)
+        if ! Win32::API::Test::can_fork()
+        || ! $LdrQueryProcessModuleInformation; #Native API changed, thats ok
+
     is(GetAPITestDLLLoadCount($LdrQueryProcessModuleInformation), 1,
        "DLL load count is 1 before fork");
     my ($child, $parent);
@@ -213,4 +217,4 @@ sub GetAPITestDLLLoadCount{
             return $_->{LoadCount};
         }
     }
-}
+}

Callback/t/ithreads.t

@@ -3,29 +3,33 @@ use strict;
 use warnings;
 
 use Win32::API::Callback;
+use Win32::API::Test;
 use Test::More;
 use Config;
+
 plan tests => 1;
-#this test was originally useless without the Windows debugging heap, by
-#raising the alloc size to 50 MB, a call to the paging system is forced
-#a double free will get access violation rather THAN no symptoms failure mode of
-#VirtualAlloced but freed Heap memory
 
-#HeapBlock class is not public API
+# This test was originally useless without the Windows debugging heap, by
+# raising the alloc size to 50 MB, a call to the paging system is forced
+# a double free will get access violation rather THAN no symptoms failure mode of
+# VirtualAlloced but freed Heap memory
 
 SKIP: {
-    skip("This Perl doesn't have ithreads", 1) if ! $Config{'useithreads'};
-    #50 megs should be enough to force a VirtualAlloc and a VirtualFree
+    skip("This Perl doesn't have fork", 1) if ! Win32::API::Test::can_fork();
+
+    # HeapBlock class is not public API
+
+    # 50 megs should be enough to force a VirtualAlloc and a VirtualFree
     my $ptrobj = new Win32::API::Callback::HeapBlock 5000000;
     my $pid = fork();
-    if($pid) {
+    if ($pid) {
         print "in parent\n";
         { #block to force destruction on scope leave
             undef($ptrobj);
         }
         ok("didn't crash");
     }
-    else{
+    else {
         print "in child\n";
         { #block to force destruction on scope leave
             undef($ptrobj);

Test.pm

@@ -16,6 +16,16 @@ sub is_perl_64bit () {
     return;
 }
 
+sub can_fork () {
+    use Config;
+
+    my $native = $Config{d_fork} || $Config{d_pseudofork};
+    my $win32 = ($^O eq 'MSWin32' || $^O eq 'NetWare');
+    my $ithr = $Config{useithreads} and $Config{ccflags} =~ /-DPERL_IMPLICIT_SYS/;
+
+    return $native || ($win32 and $ithr);
+}
+
 sub compiler_name () {
     use Config;
     my $cc = $Config{ccname};