1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
/* GObject - GLib Type, Object, Parameter and Signal Library
* Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc.
*
* 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., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* gvaluecollector.h: GValue varargs stubs
*/
/**
* SECTION:value_collection
* @Short_description: Converting varargs to generic values
* @See_also:#GValueTable
* @Title: Varargs Value Collection
*
* The macros in this section provide the varargs parsing support needed
* in variadic GObject functions such as g_object_new() or g_object_set().
* They currently support the collection of integral types, floating point
* types and pointers.
*/
#ifndef __G_VALUE_COLLECTOR_H__
#define __G_VALUE_COLLECTOR_H__
#include <glib-object.h>
G_BEGIN_DECLS
/* we may want to add aggregate types here some day, if requested
* by users. the basic C types are covered already, everything
* smaller than an int is promoted to an integer and floats are
* always promoted to doubles for varargs call constructions.
*/
enum /*< skip >*/
{
G_VALUE_COLLECT_INT = 'i',
G_VALUE_COLLECT_LONG = 'l',
G_VALUE_COLLECT_INT64 = 'q',
G_VALUE_COLLECT_DOUBLE = 'd',
G_VALUE_COLLECT_POINTER = 'p'
};
/* vararg union holding actuall values collected
*/
/**
* GTypeCValue:
*
* A union holding one collected value.
*/
union _GTypeCValue
{
gint v_int;
glong v_long;
gint64 v_int64;
gdouble v_double;
gpointer v_pointer;
};
/**
* G_VALUE_COLLECT_INIT:
* @value: a #GValue return location. @value must contain only 0 bytes.
* @_value_type: the #GType to use for @value.
* @var_args: the va_list variable; it may be evaluated multiple times
* @flags: flags which are passed on to the collect_value() function of
* the #GTypeValueTable of @value.
* @__error: a #gchar** variable that will be modified to hold a g_new()
* allocated error messages if something fails
*
* Collects a variable argument value from a va_list. We have to
* implement the varargs collection as a macro, because on some systems
* va_list variables cannot be passed by reference.
*
* Since: 2.24
*/
#define G_VALUE_COLLECT_INIT(value, _value_type, var_args, flags, __error) \
G_STMT_START { \
GValue *_value = (value); \
guint _flags = (flags); \
GTypeValueTable *_vtable = g_type_value_table_peek (_value_type); \
gchar *_collect_format = _vtable->collect_format; \
GTypeCValue _cvalues[G_VALUE_COLLECT_FORMAT_MAX_LENGTH] = { { 0, }, }; \
guint _n_values = 0; \
\
_value->g_type = _value_type; /* value_meminit() from gvalue.c */ \
while (*_collect_format) \
{ \
GTypeCValue *_cvalue = _cvalues + _n_values++; \
\
switch (*_collect_format++) \
{ \
case G_VALUE_COLLECT_INT: \
_cvalue->v_int = va_arg ((var_args), gint); \
break; \
case G_VALUE_COLLECT_LONG: \
_cvalue->v_long = va_arg ((var_args), glong); \
break; \
case G_VALUE_COLLECT_INT64: \
_cvalue->v_int64 = va_arg ((var_args), gint64); \
break; \
case G_VALUE_COLLECT_DOUBLE: \
_cvalue->v_double = va_arg ((var_args), gdouble); \
break; \
case G_VALUE_COLLECT_POINTER: \
_cvalue->v_pointer = va_arg ((var_args), gpointer); \
break; \
default: \
g_assert_not_reached (); \
} \
} \
*(__error) = _vtable->collect_value (_value, \
_n_values, \
_cvalues, \
_flags); \
} G_STMT_END
/**
* G_VALUE_COLLECT:
* @value: a #GValue return location. @value is supposed to be initialized
* according to the value type to be collected
* @var_args: the va_list variable; it may be evaluated multiple times
* @flags: flags which are passed on to the collect_value() function of
* the #GTypeValueTable of @value.
* @__error: a #gchar** variable that will be modified to hold a g_new()
* allocated error messages if something fails
*
* Collects a variable argument value from a va_list. We have to
* implement the varargs collection as a macro, because on some systems
* va_list variables cannot be passed by reference.
*
* Note: If you are creating the @value argument just before calling this macro,
* you should use the #G_VALUE_COLLECT_INIT variant and pass the unitialized
* #GValue. That variant is faster than #G_VALUE_COLLECT.
*/
#define G_VALUE_COLLECT(value, var_args, flags, __error) G_STMT_START { \
GValue *_value = (value); \
GType _value_type = G_VALUE_TYPE (_value); \
GTypeValueTable *_vtable = g_type_value_table_peek (_value_type); \
\
if (_vtable->value_free) \
_vtable->value_free (_value); \
memset (_value->data, 0, sizeof (_value->data)); \
\
G_VALUE_COLLECT_INIT(value, _value_type, var_args, flags, __error); \
} G_STMT_END
/**
* G_VALUE_LCOPY:
* @value: a #GValue return location. @value is supposed to be initialized
* according to the value type to be collected
* @var_args: the va_list variable; it may be evaluated multiple times
* @flags: flags which are passed on to the lcopy_value() function of
* the #GTypeValueTable of @value.
* @__error: a #gchar** variable that will be modified to hold a g_new()
* allocated error messages if something fails
*
* Collects a value's variable argument locations from a va_list. Usage is
* analogous to G_VALUE_COLLECT().
*/
#define G_VALUE_LCOPY(value, var_args, flags, __error) \
G_STMT_START { \
const GValue *_value = (value); \
guint _flags = (flags); \
GType _value_type = G_VALUE_TYPE (_value); \
GTypeValueTable *_vtable = g_type_value_table_peek (_value_type); \
gchar *_lcopy_format = _vtable->lcopy_format; \
GTypeCValue _cvalues[G_VALUE_COLLECT_FORMAT_MAX_LENGTH] = { { 0, }, }; \
guint _n_values = 0; \
\
while (*_lcopy_format) \
{ \
GTypeCValue *_cvalue = _cvalues + _n_values++; \
\
switch (*_lcopy_format++) \
{ \
case G_VALUE_COLLECT_INT: \
_cvalue->v_int = va_arg ((var_args), gint); \
break; \
case G_VALUE_COLLECT_LONG: \
_cvalue->v_long = va_arg ((var_args), glong); \
break; \
case G_VALUE_COLLECT_INT64: \
_cvalue->v_int64 = va_arg ((var_args), gint64); \
break; \
case G_VALUE_COLLECT_DOUBLE: \
_cvalue->v_double = va_arg ((var_args), gdouble); \
break; \
case G_VALUE_COLLECT_POINTER: \
_cvalue->v_pointer = va_arg ((var_args), gpointer); \
break; \
default: \
g_assert_not_reached (); \
} \
} \
*(__error) = _vtable->lcopy_value (_value, \
_n_values, \
_cvalues, \
_flags); \
} G_STMT_END
/**
* G_VALUE_COLLECT_FORMAT_MAX_LENGTH:
*
* The maximal number of #GTypeCValue<!-- -->s which can be collected for a
* single #GValue.
*/
#define G_VALUE_COLLECT_FORMAT_MAX_LENGTH (8)
G_END_DECLS
#endif /* __G_VALUE_COLLECTOR_H__ */
|
