[io grant] Implement proper args for IO::Handle.lock

src/core/CompUnit/PrecompilationStore/File.pm

@@ -121,7 +121,7 @@ class CompUnit::PrecompilationStore::File does CompUnit::PrecompilationStore {
             $!lock //= $.prefix.concat-with('.lock').open(:create, :rw);
             $!lock-count++
         }
-        $!lock.lock(2) if $acquire-file-lock == 0;
+        $!lock.lock if $acquire-file-lock == 0;
     }
 
     method unlock() {

src/core/CompUnit/Repository/Installation.pm

@@ -227,7 +227,7 @@ sub MAIN(:$name is copy, :$auth, :$ver, *@, *%) {
         my @*MODULES;
         my $path   = self!writeable-path or die "No writeable path found, $.prefix not writeable";
         my $lock = $.prefix.concat-with('repo.lock').open(:create, :w);
-        $lock.lock(2);
+        $lock.lock;
 
         my $version = self!repository-version;
         self.upgrade-repository unless $version == 2;

src/core/Exception.pm

@@ -466,6 +466,11 @@ my class X::IO::Copy does X::IO {
     }
 }
 
+my class X::IO::Lock does X::IO {
+    has $.lock-type;
+    method message() { "Could not obtain $.lock-type lock: $.os-error" }
+}
+
 my class X::IO::Move does X::IO {
     has $.from;
     has $.to;

src/core/IO/Handle.pm

@@ -753,8 +753,15 @@ my class IO::Handle {
         self.opened && nqp::p6bool(nqp::isttyfh($!PIO))
     }
 
-    method lock(IO::Handle:D: Int:D $flag) {
-        nqp::lockfh($!PIO, $flag)
+    method lock(IO::Handle:D:
+        Bool:D :$non-blocking = False, Bool:D :$shared = False --> True
+    ) {
+        nqp::lockfh($!PIO, 0x10*$non-blocking + $shared);
+        CATCH { default {
+            fail X::IO::Lock.new: :os-error(.Str),
+                :lock-type( 'non-' x $non-blocking ~ 'blocking, '
+                    ~ ($shared ?? 'shared' !! 'exclusive') );
+        }}
     }
 
     method unlock(IO::Handle:D: --> True) {

t/spectest.data

@@ -976,6 +976,7 @@ S32-io/dir.t
 S32-io/file-tests.t
 S32-io/indir.t
 S32-io/io-handle.t
+S32-io/lock.t                   # slow
 S32-io/socket-host-port-split.t
 S32-io/socket-fail-invalid-values.t
 S32-io/io-special.t