[function] Make function objects dynamically creatable and ref-counted.

14 files changed, 218 insertions, 57 deletions

diff --git a/ccss-doc/ccss-sections.txt b/ccss-doc/ccss-sections.txt
index 57a9ec0..b3bd7e9 100644
--- a/ccss-doc/ccss-sections.txt
+++ b/ccss-doc/ccss-sections.txt
@@ -72,6 +72,17 @@ ccss_color_parse
 </SECTION>
 
 <SECTION>
+<TITLE>ccss_function_t</TITLE>
+<FILE>function</FILE>
+ccss_function_f
+ccss_function_t
+ccss_function_create
+ccss_function_destroy
+ccss_function_get_reference_count
+ccss_function_reference
+</SECTION>
+
+<SECTION>
 <TITLE>ccss_grammar_t</TITLE>
 <FILE>grammar</FILE>
 ccss_grammar_t
@@ -181,10 +192,3 @@ ccss_property_get_state
 ccss_property_state_serialize
 </SECTION>
 
-<SECTION>
-<TITLE>ccss_function_t</TITLE>
-<FILE>function</FILE>
-ccss_function_f
-ccss_function_t
-</SECTION>
-
diff --git a/ccss-gtk/ccss-gtk-functions.c b/ccss-gtk/ccss-gtk-functions.c
index c2c5106..aabd24d 100644
--- a/ccss-gtk/ccss-gtk-functions.c
+++ b/ccss-gtk/ccss-gtk-functions.c
@@ -367,20 +367,20 @@ darker (GSList const	*args,
 						      result.blue / 65535.0);
 }
 
-static ccss_function_t const _functions[] =
-{
-  { "url",		url,		NULL },
-  { "gtk-color",	color,		NULL },
-  { "gtk-mix",		mix,		NULL },
-  { "gtk-shade",	shade,		NULL },
-  { "gtk-lighter",	lighter,	NULL },
-  { "gtk-darker",	darker,		NULL },
-  { NULL }
-};
-
-ccss_function_t const *
-ccss_gtk_functions_get_vtable (void)
+ccss_function_t *
+ccss_gtk_functions_peek_vtable (void)
 {
+	static ccss_function_t _functions[] =
+	{
+	  { "url",		url,		1 },
+	  { "gtk-color",	color,		1 },
+	  { "gtk-mix",		mix,		1 },
+	  { "gtk-shade",	shade,		1 },
+	  { "gtk-lighter",	lighter,	1 },
+	  { "gtk-darker",	darker,		1 },
+	  { NULL }
+	};
+
 	return _functions;
 }
 
diff --git a/ccss-gtk/ccss-gtk-functions.h b/ccss-gtk/ccss-gtk-functions.h
index b79de14..f6a8fed 100644
--- a/ccss-gtk/ccss-gtk-functions.h
+++ b/ccss-gtk/ccss-gtk-functions.h
@@ -32,7 +32,8 @@
 
 CCSS_BEGIN_DECLS
 
-ccss_function_t const * ccss_gtk_functions_get_vtable (void);
+ccss_function_t *
+ccss_gtk_functions_peek_vtable (void);
 
 CCSS_END_DECLS
 
diff --git a/ccss-gtk/ccss-gtk-grammar.c b/ccss-gtk/ccss-gtk-grammar.c
index e1fe3c0..8cc8b7c 100644
--- a/ccss-gtk/ccss-gtk-grammar.c
+++ b/ccss-gtk/ccss-gtk-grammar.c
@@ -22,6 +22,7 @@
 #include <string.h>
 #include <gtk/gtk.h>
 #include <ccss-cairo/ccss-cairo.h>
+#include <ccss/ccss-function-impl.h>
 #include "ccss-gtk-grammar.h"
 #include "ccss-gtk-functions.h"
 #include "ccss-gtk-property.h"
@@ -50,7 +51,7 @@ ccss_gtk_grammar_create (void)
 	ccss_gtk_property_set_fallback_class (fallback_property_class);
 
 	ccss_grammar_add_properties (self, ccss_gtk_property_get_property_classes ());
-	ccss_grammar_add_functions (self, ccss_gtk_functions_get_vtable ());
+	ccss_grammar_add_functions (self, ccss_gtk_functions_peek_vtable ());
 
 	return self;
 }
diff --git a/ccss/Makefile.am b/ccss/Makefile.am
index 106e976..513fd2e 100644
--- a/ccss/Makefile.am
+++ b/ccss/Makefile.am
@@ -39,6 +39,7 @@ libccss_1_la_SOURCES = \
 	ccss-border-image-parser.h \
 	ccss-color.c \
 	ccss-color-parser.c \
+	ccss-function.c \
 	ccss-grammar.c \
 	ccss-grammar-function.c \
 	ccss-grammar-parse.c \
diff --git a/ccss/ccss-function-impl.h b/ccss/ccss-function-impl.h
index b6d19c2..fc08864 100644
--- a/ccss/ccss-function-impl.h
+++ b/ccss/ccss-function-impl.h
@@ -35,26 +35,14 @@
 
 CCSS_BEGIN_DECLS
 
-/* Let's just forward declare this, so we don't have to pull in <glib.h>. */
-struct _GSList;
-
-/**
- * ccss_function_f:
- * @args:	argument-list passed to the function.
- * @user_data:	user data associated to the function handler.
- * 
- * Prototype for a custom `CSS function' handler.
- *
- * Returns: the function's result as a string.
- **/
-typedef char * (*ccss_function_f) (struct _GSList const	*args,
-				   void			*user_data);
+/* Avoid circular dependencies. */
+struct ccss_grammar_;
 
 /**
  * ccss_function_t:
- * @name:	identifier of the function, as used in CSS.
- * @function:	handler, see #ccss_function_f.
- * @user_data:	data to pass to the function handler.
+ * @name:		identifier of the function, as used in CSS.
+ * @function:		handler, see #ccss_function_f.
+ * @reference_count:	the reference count.
  *
  * This datastructure represents one line in the libccss' consumers vtable.
  **/
@@ -62,9 +50,13 @@ struct ccss_function_ {
 	/*< private >*/
 	CCSS_DEPRECATED (char const		*name);
 	CCSS_DEPRECATED (ccss_function_f	 function);
-	CCSS_DEPRECATED (void			*user_data);
+	CCSS_DEPRECATED (unsigned int		 reference_count);
 };
 
+void
+ccss_grammar_add_functions	(struct ccss_grammar_		*self,
+				 ccss_function_t		*functions);
+
 CCSS_END_DECLS
 
 #endif /* CCSS_FUNCTION_IMPL_H */
diff --git a/ccss/ccss-function.c b/ccss/ccss-function.c
new file mode 100644
index 0000000..a4b9a2c
--- /dev/null
+++ b/ccss/ccss-function.c
@@ -0,0 +1,110 @@
+/* vim: set ts=8 sw=8 noexpandtab: */
+
+/* The `C' CSS Library.
+ * Copyright (C) 2008 Robert Staudinger
+ *
+ * This  library is free  software; you can  redistribute it and/or
+ * modify it  under  the terms  of the  GNU Lesser  General  Public
+ * License  as published  by the Free  Software  Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed  in the hope that it will be useful,
+ * but  WITHOUT ANY WARRANTY; without even  the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License  along  with  this library;  if not,  write to  the Free
+ * Software Foundation, Inc., 51  Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+#include <glib.h>
+#include "ccss-function-impl.h"
+
+/*
+ * FIXME: move to reference counting.
+ * So statically allocated function structs will never actually be destroyed.
+ */
+
+/**
+ * ccss_function_create:
+ * @name:       function identifier as used in CSS.
+ * @function:   function pointer.
+ *
+ * Create a new function instance.
+ *
+ * Returns: a #ccss_function_t.
+ **/
+ccss_function_t *
+ccss_function_create (char const	*name,
+		      ccss_function_f	 function)
+{
+	ccss_function_t *self;
+
+	g_return_val_if_fail (name, NULL);
+	g_return_val_if_fail (function, NULL);
+
+	self = g_new0 (ccss_function_t, 1);
+	self->name = g_strdup (name);
+	self->function = function;
+
+	return self;
+}
+
+/**
+ * ccss_function_destroy:
+ *
+ * Destroy a function instance.
+ **/
+void
+ccss_function_destroy (ccss_function_t *self)
+{
+	g_return_if_fail (self);
+
+	self->reference_count--;
+
+	if (0 == self->reference_count) {
+		/* This string is owned for dynamically created functions. */
+		g_free ((char *) self->name);
+		g_free (self);
+	}
+}
+
+/**
+ * ccss_function_reference:
+ * @self: a #ccss_function_t.
+ *
+ * Increases the reference count on @self by one. This prevents @self from being
+ * destroyed until a matching call to ccss_function_destroy() is made.
+ *
+ * The number of references to a #ccss_function_t can be acquired using
+ * ccss_function_get_reference_count().
+ *
+ * Returns: the referenced #ccss_function_t.
+ **/
+ccss_function_t *
+ccss_function_reference (ccss_function_t *self)
+{
+	g_return_val_if_fail (self, NULL);
+
+	self->reference_count++;
+
+	return self;
+}
+
+/**
+ * ccss_function_get_reference_count:
+ * @self: a #ccss_function_t.
+ *
+ * Returns: the current reference count of @self.
+ *	    If @self is a nil object, 0 will be returned.
+ **/
+unsigned int
+ccss_function_get_reference_count (ccss_function_t const *self)
+{
+	g_return_val_if_fail (self, 0);
+
+	return self->reference_count;
+}
+
diff --git a/ccss/ccss-function.h b/ccss/ccss-function.h
index 4945756..0b444ce 100644
--- a/ccss/ccss-function.h
+++ b/ccss/ccss-function.h
@@ -26,8 +26,36 @@
 
 CCSS_BEGIN_DECLS
 
+/* Let's just forward declare this, so we don't have to pull in <glib.h>. */
+struct _GSList;
+
+/**
+ * ccss_function_f:
+ * @args:	argument-list passed to the function.
+ * @user_data:	user data associated to the function handler.
+ *
+ * Prototype for a custom `CSS function' handler.
+ *
+ * Returns: the function's result as a string.
+ **/
+typedef char * (*ccss_function_f) (struct _GSList const	*args,
+				   void			*user_data);
+
 typedef struct ccss_function_ ccss_function_t;
 
+ccss_function_t *
+ccss_function_create			(char const		*name,
+					 ccss_function_f	 function);
+
+void
+ccss_function_destroy			(ccss_function_t	*self);
+
+ccss_function_t *
+ccss_function_reference			(ccss_function_t	*self);
+
+unsigned int
+ccss_function_get_reference_count       (ccss_function_t const  *self);
+
 CCSS_END_DECLS
 
 #endif /* CCSS_FUNCTION_H */
diff --git a/ccss/ccss-grammar-function.c b/ccss/ccss-grammar-function.c
index f095dab..1649707 100644
--- a/ccss/ccss-grammar-function.c
+++ b/ccss/ccss-grammar-function.c
@@ -140,7 +140,6 @@ ccss_grammar_invoke_function (ccss_grammar_t const	*self,
 {
 	ccss_function_t const	*handler;
 	GSList			*args;
-	void			*actual_user_data;
 	char			*ret;
 
 	g_return_val_if_fail (self && function_name, NULL);
@@ -158,12 +157,7 @@ ccss_grammar_invoke_function (ccss_grammar_t const	*self,
 	args = g_slist_reverse (args);
 
 	/* dispatch */
-	if (user_data) {
-		actual_user_data = user_data;
-	} else {
-		actual_user_data = handler->user_data;
-	}
-	ret = handler->function (args, actual_user_data);
+	ret = handler->function (args, user_data);
 
 	/* free args */
 	while (args) {
diff --git a/ccss/ccss-grammar.c b/ccss/ccss-grammar.c
index 6f18498..1e2591c 100644
--- a/ccss/ccss-grammar.c
+++ b/ccss/ccss-grammar.c
@@ -51,7 +51,10 @@ ccss_grammar_create_generic (void)
 	self = g_new0 (ccss_grammar_t, 1);
 	self->reference_count = 1;
 	self->properties = g_hash_table_new (g_str_hash, g_str_equal);
-	self->functions = g_hash_table_new (g_str_hash, g_str_equal);
+	self->functions = g_hash_table_new_full (g_str_hash,
+						 g_str_equal,
+						 NULL,
+						 (GDestroyNotify) ccss_function_destroy);
 
 	ccss_grammar_add_properties (self, ccss_property_parser_get_property_classes ());
 
@@ -187,6 +190,28 @@ ccss_grammar_lookup_property (ccss_grammar_t const	*self,
 }
 
 /**
+ * ccss_grammar_add_function:
+ * @self:	a #ccss_grammar_t.
+ * @function:	a #ccss_function_t to register.
+ *
+ * Register a single custom css function handler with the grammar.
+ **/
+void
+ccss_grammar_add_function (ccss_grammar_t	*self,
+			   ccss_function_t	*function)
+{
+	g_return_if_fail (self);
+	g_return_if_fail (function);
+
+	/* Handler already exists? */
+	g_warn_if_fail (NULL == g_hash_table_lookup (self->functions, function->name));
+
+	g_hash_table_insert (self->functions,
+			     (gpointer) function->name,
+			     ccss_function_reference (function));
+}
+
+/**
  * ccss_grammar_add_functions:
  * @self:	a #ccss_grammar_t.
  * @functions:	Null-terminated array of #ccss_function_t to register.
@@ -194,8 +219,8 @@ ccss_grammar_lookup_property (ccss_grammar_t const	*self,
  * Register a set of custom css function handlers with the grammar.
  **/
 void
-ccss_grammar_add_functions (ccss_grammar_t		*self,
-			    ccss_function_t const	*functions)
+ccss_grammar_add_functions (ccss_grammar_t	*self,
+			    ccss_function_t	*functions)
 {
 	g_return_if_fail (self && functions);
 
@@ -206,7 +231,7 @@ ccss_grammar_add_functions (ccss_grammar_t		*self,
 
 		g_hash_table_insert (self->functions,
 				     (gpointer) functions[i].name,
-				     (gpointer) &functions[i]);
+				     ccss_function_reference (&functions[i]));
 	}
 }
 
diff --git a/ccss/ccss-grammar.h b/ccss/ccss-grammar.h
index 71d5512..9dd49bb 100644
--- a/ccss/ccss-grammar.h
+++ b/ccss/ccss-grammar.h
@@ -55,8 +55,8 @@ ccss_grammar_lookup_property	(ccss_grammar_t const		*self,
 				 char const			*name);
 
 void
-ccss_grammar_add_functions	(ccss_grammar_t			*self,
-				 ccss_function_t const		*functions);
+ccss_grammar_add_function	(ccss_grammar_t			*self,
+				 ccss_function_t		*function);
 
 ccss_function_t const *
 ccss_grammar_lookup_function	(ccss_grammar_t const		*self,
diff --git a/ccss/ccss.sym b/ccss/ccss.sym
index a124d57..578ceea 100644
--- a/ccss/ccss.sym
+++ b/ccss/ccss.sym
@@ -28,6 +28,11 @@ ccss_color_get_blue
 ccss_color_get_green
 ccss_color_get_red
 ccss_color_parse
+ccss_function_create
+ccss_function_destroy
+ccss_function_get_reference_count
+ccss_function_reference
+ccss_grammar_add_function
 ccss_grammar_add_functions
 ccss_grammar_add_properties
 ccss_grammar_create_css
diff --git a/examples/example-3.c b/examples/example-3.c
index 1b6367e..1a76996 100644
--- a/examples/example-3.c
+++ b/examples/example-3.c
@@ -52,9 +52,9 @@ url (GSList const	*args,
 	return uri;
 }
 
-static ccss_function_t const _functions[] = 
+static ccss_function_t _functions[] =
 {
-  { "url",	url,	NULL },
+  { "url",	url,	1 },
   { NULL }
 };
 
diff --git a/examples/example-5.c b/examples/example-5.c
index 3c50155..6fc3a5f 100644
--- a/examples/example-5.c
+++ b/examples/example-5.c
@@ -52,9 +52,9 @@ url (GSList const	*args,
 	return uri;
 }
 
-static ccss_function_t const _functions[] = 
+static ccss_function_t _functions[] =
 {
-  { "url",	url,	NULL },
+  { "url",	url,	1 },
   { NULL }
 };