support optional output args in the cli

the cli interface now supports optional output args ... C API next

ChangeLog

@@ -4,6 +4,7 @@
 - added VIPS_ARGUMENT_APPEND to help control arg ordering
 - generate has a 'stop' param to signal successful early termination
 - added optional output args, eg. x/y for min
+- CLI supports optional output args
 
 10/8/11 started 7.26.3
 - don't use G_VALUE_COLLECT_INIT(), many platforms do not have a glib this

TODO

@@ -1,34 +1,3 @@
-- see TODO comment on vips_call_options_set()
-
-
-
-
-- cmd line interface needs to print optional output args, if requested
-  
-  eg. 
-
-  	$ vips min fred.v
-	12
-  	$ vips min -x fred.v
-	12
-	300
-
-  the switch is there, but breaks an assert:
-
-	$ vips min -x babe.jpg
-	VIPS:ERROR:object.c:1178:vips_object_set_argument_from_string: assertion
-	failed: (argument_class->flags & VIPS_ARGUMENT_INPUT)
-	Aborted
-
-  options are being made incorrectly:
-
-	$ vips min --help
-	  -y, --y=gint                      Vertical position of minimum
-
-  --y should not have an arg
-
-
-
 - C interface needs to look for optional output args in final psss, eg.
 
 	vips_min( im, &min,

libvips/include/vips/object.h

@@ -134,6 +134,10 @@ typedef struct _VipsArgumentClass {
 typedef struct _VipsArgumentInstance {
 	VipsArgument parent;
 
+	/* The class we are part of.
+	 */
+	VipsArgumentClass *argument_class;
+
 	/* The object we are attached to.
 	 */
 	VipsObject *object;
@@ -154,9 +158,9 @@ typedef struct _VipsArgumentInstance {
 typedef GHashTable VipsArgumentTable;
 
 VipsArgumentInstance *vips__argument_get_instance( VipsArgumentClass *,
-	VipsObject *);
+	VipsObject * );
 VipsArgument *vips__argument_table_lookup( VipsArgumentTable *, 
-	GParamSpec *);
+	GParamSpec * );
 void vips__object_set_member( VipsObject *object, GParamSpec *pspec,
 	GObject **member, GObject *argument );
 typedef void *(*VipsArgumentMapFn)( VipsObject *, GParamSpec *,

libvips/iofuncs/object.c

@@ -366,6 +366,7 @@ vips_argument_init( VipsObject *object )
 			argument_instance = g_new( VipsArgumentInstance, 1 );
 
 			((VipsArgument *) argument_instance)->pspec = pspec;
+			argument_instance->argument_class = argument_class;
 			argument_instance->object = object;
 			argument_instance->assigned = FALSE;
 			argument_instance->close_id = 0;

libvips/iofuncs/operation.c

@@ -504,7 +504,7 @@ vips_call_split( const char *operation_name, va_list optional, ... )
 }
 
 static void *
-vips_call_find_pspec_char( VipsObject *object,
+vips_call_find_pspec( VipsObject *object,
 	GParamSpec *pspec,
 	VipsArgumentClass *argument_class,
 	VipsArgumentInstance *argument_instance,
@@ -512,31 +512,42 @@ vips_call_find_pspec_char( VipsObject *object,
 {
 	const char *name = (const char *) a;
 
+	/* One char names we assume are "-x" style abbreviations, longer names
+	 * we match the whole string.
+	 */
 	if( !(argument_class->flags & VIPS_ARGUMENT_REQUIRED) &&
 		(argument_class->flags & VIPS_ARGUMENT_CONSTRUCT) &&
-		!argument_instance->assigned &&
+		!argument_instance->assigned ) 
-		g_param_spec_get_name( pspec )[0] == name[0] ) 
+		if( (strlen( name ) == 1 && 
-		return( pspec );
+			g_param_spec_get_name( pspec )[0] == name[0]) ||
+			strcmp( g_param_spec_get_name( pspec ), name  ) == 0 ) 
+			return( argument_instance );
 
 	return( NULL );
 }
 
-static void *
+/* Keep this stuff around for output args.
-vips_call_find_pspec_name( VipsObject *object,
+ */
-	GParamSpec *pspec,
+typedef struct _VipsCallOptionOutput {
-	VipsArgumentClass *argument_class,
+	VipsArgumentInstance *argument_instance;
-	VipsArgumentInstance *argument_instance,
+	const char *value;
-	void *a, void *b )
+} VipsCallOptionOutput;
+
+static void
+vips_call_option_output( VipsObject *object,
+	VipsCallOptionOutput *output )
 {
-	const char *name = (const char *) a;
+	VipsArgumentInstance *argument_instance = output->argument_instance;
+	GParamSpec *pspec = ((VipsArgument *) argument_instance)->pspec;
 
-	if( !(argument_class->flags & VIPS_ARGUMENT_REQUIRED) &&
+	if( vips_object_get_argument_to_string( object, 
-		(argument_class->flags & VIPS_ARGUMENT_CONSTRUCT) &&
+		g_param_spec_get_name( pspec ), output->value ) ) {
-		!argument_instance->assigned &&
+		/* FIXME .. Hmm what can we do here? If an arg is image
-		strcmp( g_param_spec_get_name( pspec ), name  ) == 0 ) 
+		 * output, for example, we will lose the error.
-		return( pspec );
+		 */
+	}
 
-	return( NULL );
+	g_free( output );
 }
 
 static gboolean
@@ -545,6 +556,8 @@ vips_call_options_set( const gchar *option_name, const gchar *value,
 {
 	VipsOperation *operation = (VipsOperation *) data;
 	const char *name;
+	VipsArgumentInstance *argument_instance;
+	VipsArgumentClass *argument_class;
 	GParamSpec *pspec;
 
 	VIPS_DEBUG_MSG( "vips_call_options_set: %s = %s\n", 
@@ -555,34 +568,39 @@ vips_call_options_set( const gchar *option_name, const gchar *value,
 	for( name = option_name; *name == '-'; name++ )
 		;
 
-	/* If this is a single-character name, find the first unset pspec with
+	if( !(argument_instance = (VipsArgumentInstance *) 
-	 * that initial. Otherwise, search for a spec of that name.
+		vips_argument_map( 
-	 */
-	if( strlen( name ) == 1 ) 
-		pspec = (GParamSpec *) vips_argument_map( 
 			VIPS_OBJECT( operation ),
-			vips_call_find_pspec_char, 
+			vips_call_find_pspec, (void *) name, NULL )) ) {
-			(void *) name, NULL );
-	else
-		pspec = (GParamSpec *) vips_argument_map( 
-			VIPS_OBJECT( operation ),
-			vips_call_find_pspec_name, 
-			(void *) name, NULL );
-	if( !pspec ) {
 		vips_error( VIPS_OBJECT( operation )->nickname, 
 			_( "unknown argument '%s'" ), name );
 		return( FALSE );
 	}
+	argument_class = argument_instance->argument_class;
+	pspec = ((VipsArgument *) argument_instance)->pspec;
 
-	/*
+	if( (argument_class->flags & VIPS_ARGUMENT_INPUT) ) {
-	 *
+		if( vips_object_set_argument_from_string( 
-	 * FIXME ... for output args, need to attach a close callback to
+			VIPS_OBJECT( operation ),
-	 * operation to write the value
+			g_param_spec_get_name( pspec ), value ) )
-	 *
+			return( FALSE );
-	 */
+	}
-	if( vips_object_set_argument_from_string( VIPS_OBJECT( operation ), 
+	else if( (argument_class->flags & VIPS_ARGUMENT_OUTPUT) ) {
-		name, value ) )
+		VipsCallOptionOutput *output;
-		return( FALSE );
+
+		/* We can't do output now, we have to attach a callback to do
+		 * the processing after the operation has run.
+		 *
+		 * FIXME ... something like posteval or postbuild might be
+		 * better for this?
+		 */
+		output = g_new( VipsCallOptionOutput, 1 );
+		output->argument_instance = argument_instance;
+		output->value = value;
+		g_signal_connect( operation, "preclose",
+			G_CALLBACK( vips_call_option_output ),
+			output );
+	}
 
 	return( TRUE );
 }