feat: per call context

Author: G4Vi

Extism/lib/Extism/CurrentPlugin.pm

@@ -8,6 +8,7 @@ use Extism::XS qw(current_plugin_memory
     current_plugin_memory_alloc
     current_plugin_memory_length
     current_plugin_memory_free
+    current_plugin_host_context
     CopyToPtr);
 
 use version 0.77;
@@ -53,4 +54,8 @@ sub memory_alloc_and_store {
     return $ptr;
 }
 
+sub host_context {
+    current_plugin_host_context($Extism::CurrentPlugin::instance)
+}
+
 1; # End of Extism::CurrentPlugin

Extism/lib/Extism/Plugin.pm

@@ -59,14 +59,14 @@ sub new {
 # passed to the plugin. If INPUT is a reference, the referenced item will be
 # encoded with json and then passed to the plugin.
 sub call {
-    my ($self, $func_name, $input) = @_;
+    my ($self, $func_name, $input, $host_context) = @_;
     $input //= '';
     my $type = reftype($input);
     if ($type) {
         $input = $$input if($type eq 'SCALAR');
         $input = encode_json($input);
     }
-    my $rc = plugin_call($$self, $func_name, $input, length($input));
+    my $rc = plugin_call($$self, $func_name, $input, length($input), $host_context);
     if ($rc != 0) {
         die Extism::Plugin::CallException->new($rc, plugin_error($$self));
     }

Extism/lib/Extism/XS.pm

@@ -33,6 +33,7 @@ our @EXPORT_OK = qw(
     current_plugin_memory_alloc
     current_plugin_memory_length
     current_plugin_memory_free
+    current_plugin_host_context
     log_file
     log_custom
     log_drain

Extism/lib/Extism/XS.xs

@@ -109,13 +109,14 @@ plugin_new_error_free(err);
         extism_plugin_new_error_free(err);
 
 int32_t
-plugin_call(plugin, func_name, data, data_len)
+plugin_call(plugin, func_name, data, data_len, host_context=&PL_sv_undef)
     ExtismPlugin *plugin
     const char *func_name
     const uint8_t *data
     ExtismSize data_len
+    SV *host_context
     CODE:
-        RETVAL = extism_plugin_call(plugin, func_name, data, data_len);
+        RETVAL = extism_plugin_call_with_host_context(plugin, func_name, data, data_len, host_context);
     OUTPUT:
         RETVAL
 
@@ -261,6 +262,17 @@ current_plugin_memory_free(plugin, handle)
     CODE:
         extism_current_plugin_memory_free(plugin, handle);
 
+SV *
+current_plugin_host_context(plugin)
+    ExtismCurrentPlugin *plugin
+    CODE:
+        RETVAL = extism_current_plugin_host_context(plugin);
+        if (RETVAL != &PL_sv_undef) {
+            SvREFCNT_inc_simple_NN(RETVAL);
+        }
+    OUTPUT:
+        RETVAL
+
 void
 log_file(filename, log_level)
     const char *filename

Extism/t/02-extism.t

@@ -7,7 +7,7 @@ use Extism ':all';
 use JSON::PP qw(encode_json decode_json);
 use File::Temp qw(tempfile);
 use Devel::Peek qw(Dump);
-plan tests => 45;
+plan tests => 48;
 
 # ...
 ok(Extism::version());
@@ -213,3 +213,30 @@ eval {
 ok($@);
 ok($@->{code} != 0);
 ok($@->{message});
+
+# Test host_context
+{
+    my $voidfunction = Extism::Function->new("hello_void", [], [], sub {
+        ok(! defined Extism::CurrentPlugin::host_context);
+        return;
+    });
+    my $paramsfunction = Extism::Function->new("hello_params", [Extism_F64, Extism_I32, Extism_F32, Extism_I64], [Extism_I64], sub {
+        # not called
+    });
+    my $fplugin = Extism::Plugin->new($hostwasm, {functions => [$voidfunction, $paramsfunction], wasi => 1});
+    $fplugin->call('call_hello_void');
+}
+{
+    my %context = ( abc => 123);
+    my $voidfunction = Extism::Function->new("hello_void", [], [], sub {
+        my $ctx = Extism::CurrentPlugin::host_context;
+        is_deeply($ctx, \%context);
+        ok($ctx == \%context);
+        return;
+    });
+    my $paramsfunction = Extism::Function->new("hello_params", [Extism_F64, Extism_I32, Extism_F32, Extism_I64], [Extism_I64], sub {
+        # not called
+    });
+    my $fplugin = Extism::Plugin->new($hostwasm, {functions => [$voidfunction, $paramsfunction], wasi => 1});
+    $fplugin->call('call_hello_void', '', \%context);
+}