1/* valagvaluemodule.vala
2 *
3 * Copyright (C) 2019  Rico Tzschichholz
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2.1 of the License, or (at your option) any later version.
9
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13 * Lesser General Public License for more details.
14
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
18 *
19 * Author:
20 * 	Rico Tzschichholz <ricotz@ubuntu.com>
21 */
22
23public class Vala.GValueModule : GAsyncModule {
24	public override void visit_cast_expression (CastExpression expr) {
25		unowned DataType? value_type = expr.inner.value_type;
26		unowned DataType? target_type = expr.type_reference;
27
28		if (expr.is_non_null_cast || value_type == null || gvalue_type == null
29		    || value_type.type_symbol != gvalue_type || target_type.type_symbol == gvalue_type
30		    || get_ccode_type_id (target_type) == "") {
31			base.visit_cast_expression (expr);
32			return;
33		}
34
35		generate_type_declaration (expr.type_reference, cfile);
36
37		// explicit conversion from GValue
38		var ccall = new CCodeFunctionCall (get_value_getter_function (target_type));
39		CCodeExpression gvalue;
40		if (value_type.nullable) {
41			gvalue = get_cvalue (expr.inner);
42		} else {
43			gvalue = new CCodeUnaryExpression (CCodeUnaryOperator.ADDRESS_OF, get_cvalue (expr.inner));
44		}
45		ccall.add_argument (gvalue);
46
47		if (value_type.is_disposable ()) {
48			var temp_var = get_temp_variable (value_type, true, expr, false);
49			emit_temp_var (temp_var);
50			var temp_ref = get_variable_cexpression (temp_var.name);
51			ccode.add_assignment (temp_ref, get_cvalue (expr.inner));
52
53			// value needs to be kept alive until the end of this block
54			temp_ref_values.insert (0, get_local_cvalue (temp_var));
55		}
56
57		CCodeExpression rv = ccall;
58
59		if (expr != null && target_type is ArrayType) {
60			// null-terminated string array
61			var len_call = new CCodeFunctionCall (new CCodeIdentifier ("g_strv_length"));
62			len_call.add_argument (rv);
63			append_array_length (expr, len_call);
64		} else if (target_type is StructValueType) {
65			CodeNode node = expr != null ? (CodeNode) expr : target_type;
66			var temp_value = create_temp_value (target_type, true, node, true);
67			var ctemp = get_cvalue_ (temp_value);
68
69			rv = new CCodeUnaryExpression (CCodeUnaryOperator.POINTER_INDIRECTION, new CCodeCastExpression (rv, get_ccode_name (new PointerType (target_type))));
70			var holds = new CCodeFunctionCall (new CCodeIdentifier ("G_VALUE_HOLDS"));
71			holds.add_argument (gvalue);
72			holds.add_argument (new CCodeIdentifier (get_ccode_type_id (target_type)));
73			var cond = new CCodeBinaryExpression (CCodeBinaryOperator.AND, holds, ccall);
74			var warn = new CCodeFunctionCall (new CCodeIdentifier ("g_warning"));
75			warn.add_argument (new CCodeConstant ("\"Invalid GValue unboxing (wrong type or NULL)\""));
76			var fail = new CCodeCommaExpression ();
77			fail.append_expression (warn);
78			fail.append_expression (ctemp);
79			rv = new CCodeConditionalExpression (cond, rv,  fail);
80		}
81
82		set_cvalue (expr, rv);
83	}
84
85	public override CCodeExpression get_value_getter_function (DataType type_reference) {
86		var array_type = type_reference as ArrayType;
87		if (type_reference.type_symbol != null) {
88			return new CCodeIdentifier (get_ccode_get_value_function (type_reference.type_symbol));
89		} else if (array_type != null && array_type.element_type.type_symbol == string_type.type_symbol) {
90			// G_TYPE_STRV
91			return new CCodeIdentifier ("g_value_get_boxed");
92		} else {
93			return new CCodeIdentifier ("g_value_get_pointer");
94		}
95	}
96
97	public override CCodeExpression get_value_setter_function (DataType type_reference) {
98		var array_type = type_reference as ArrayType;
99		if (type_reference.type_symbol != null) {
100			return new CCodeIdentifier (get_ccode_set_value_function (type_reference.type_symbol));
101		} else if (array_type != null && array_type.element_type.type_symbol == string_type.type_symbol) {
102			// G_TYPE_STRV
103			return new CCodeIdentifier ("g_value_set_boxed");
104		} else {
105			return new CCodeIdentifier ("g_value_set_pointer");
106		}
107	}
108
109	public override CCodeExpression get_value_taker_function (DataType type_reference) {
110		var array_type = type_reference as ArrayType;
111		if (type_reference.type_symbol != null) {
112			return new CCodeIdentifier (get_ccode_take_value_function (type_reference.type_symbol));
113		} else if (array_type != null && array_type.element_type.type_symbol == string_type.type_symbol) {
114			// G_TYPE_STRV
115			return new CCodeIdentifier ("g_value_take_boxed");
116		} else {
117			return new CCodeIdentifier ("g_value_set_pointer");
118		}
119	}
120}
121