WIP: Refactoring of the library and symbols

src/ld-lua.c

@@ -0,0 +1,195 @@
+/*
+ * ld-lua.c
+ *
+ * This file is a part of logdiag.
+ * Copyright Přemysl Janouch 2010. All rights reserved.
+ *
+ * See the file LICENSE for licensing information.
+ *
+ */
+
+#include <gtk/gtk.h>
+#include <lua.h>
+#include <lualib.h>
+#include <lauxlib.h>
+
+#include "config.h"
+
+#include "ld-symbol-library.h"
+#include "ld-lua.h"
+
+
+/* TODO */
+/* A virtual superclass can be made for this. */
+
+/* Lua state belongs to the library.
+ * One Lua file should be able to register multiple symbols.
+ */
+/* How does the application call the function for rendering?
+ *   logdiag.symbols -- readonly table (from lua) -- this can be probably
+ *     accomplished using a custom metatable that errors out on newindex,
+ *     items will be added to this table only in C.
+ *   logdiag.symbols[ident].render(cr) -- here "ident" is the full path
+ *     to this symbol
+ *   logdiag.symbols[ident].names[lang, area, terminals] -- these
+ *     subarrays need not be in this array
+ *
+ */
+
+static void *
+ld_lua_alloc (void *ud, void *ptr, size_t osize, size_t nsize);
+
+
+static int
+ld_lua_logdiag_register (lua_State *L);
+
+static luaL_Reg ld_lua_logdiag_lib[] =
+{
+	{"register", ld_lua_logdiag_register},
+	{NULL, NULL}
+};
+
+
+static int
+ld_lua_cairo_move_to (lua_State *L);
+static int
+ld_lua_cairo_line_to (lua_State *L);
+static int
+ld_lua_cairo_stroke (lua_State *L);
+static int
+ld_lua_cairo_stroke_preserve (lua_State *L);
+static int
+ld_lua_cairo_fill (lua_State *L);
+static int
+ld_lua_cairo_fill_preserve (lua_State *L);
+
+static luaL_Reg ld_lua_cairo_table[] =
+{
+	{"move_to", ld_lua_cairo_move_to},
+	{"line_to", ld_lua_cairo_line_to},
+	{"stroke", ld_lua_cairo_stroke},
+	{"stroke_preserve", ld_lua_cairo_stroke_preserve},
+	{"fill", ld_lua_cairo_fill},
+	{"fill_preserve", ld_lua_cairo_fill_preserve},
+	{NULL, NULL}
+};
+
+/* ===== Generic =========================================================== */
+
+lua_State *
+ld_lua_init (void)
+{
+	lua_State *L;
+
+	L = lua_newstate (ld_lua_alloc, NULL);
+	g_return_val_if_fail (L != NULL, NULL);
+
+	/* TODO: lua_atpanic () */
+
+	/* Load some safe libraries. */
+	lua_pushcfunction (L, luaopen_string);
+	lua_call (L, 0, 0);
+
+	lua_pushcfunction (L, luaopen_table);
+	lua_call (L, 0, 0);
+
+	lua_pushcfunction (L, luaopen_math);
+	lua_call (L, 0, 0);
+
+	/* Load the application library. */
+	luaL_register (L, "logdiag", ld_lua_logdiag_lib);
+}
+
+void
+ld_lua_destroy (lua_State *L)
+{
+	lua_close (L);
+}
+
+static void *
+ld_lua_alloc (void *ud, void *ptr, size_t osize, size_t nsize)
+{
+	if (!nsize)
+	{
+		g_free (ptr);
+		return NULL;
+	}
+	else
+		return g_try_realloc (ptr, nsize);
+}
+
+/* ===== Application library =============================================== */
+
+static int
+ld_lua_logdiag_register (lua_State *L)
+{
+	/* TODO: Create a symbol. */
+	/* XXX: Shouldn't this function be a closure with LdLibrary userdata?
+	 *      It is also possible to have the userdata in the "logdiag" table.
+	 */
+
+#if 0
+	lua_newtable (L);
+
+	/* TODO: Push a function. */
+	lua_call (L, 1, 0);
+#endif /* 0 */
+}
+
+/* ===== Cairo ============================================================= */
+
+static void
+push_cairo_object (lua_State *L, cairo_t *cr)
+{
+	luaL_Reg *fn;
+
+	/* Create a table. */
+	lua_newtable (L);
+
+	/* Add methods. */
+	for (fn = ld_lua_cairo_table; fn->name; fn++)
+	{
+		lua_pushlightuserdata (L, cr);
+		lua_pushcclosure (L, fn->func, 1);
+		lua_setfield (L, -2, fn->name);
+	}
+}
+
+static int
+ld_lua_cairo_move_to (lua_State *L)
+{
+	return 0;
+}
+
+static int
+ld_lua_cairo_line_to (lua_State *L)
+{
+	return 0;
+}
+
+static int
+ld_lua_cairo_stroke (lua_State *L)
+{
+	return 0;
+}
+
+static int
+ld_lua_cairo_stroke_preserve (lua_State *L)
+{
+	return 0;
+}
+
+static int
+ld_lua_cairo_fill (lua_State *L)
+{
+	return 0;
+}
+
+static int
+ld_lua_cairo_fill_preserve (lua_State *L)
+{
+	return 0;
+}
+
+
+