--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/glib/gobject/gvalue.c Fri Apr 16 16:46:38 2010 +0300
@@ -0,0 +1,582 @@
+/* GObject - GLib Type, Object, Parameter and Signal Library
+ * Copyright (C) 1997-1999, 2000-2001 Tim Janik and Red Hat, Inc.
+ * Portions copyright (c) 2006-2009 Nokia Corporation. All rights reserved.
+ *
+ * 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.
+ */
+
+/*
+ * FIXME: MT-safety
+ */
+
+#include "config.h"
+
+#include <string.h>
+
+#include "gvalue.h"
+#include "gvaluecollector.h"
+#include "gbsearcharray.h"
+#include "gobjectalias.h"
+
+#ifdef __SYMBIAN32__
+#include "gobject_wsd.h"
+#endif /* __SYMBIAN32__ */
+
+/**
+ * SECTION:generic_values
+ * @short_description: A polymorphic type that can hold values of any
+ * other type
+ * @see_also: The fundamental types which all support #GValue
+ * operations and thus can be used as a type initializer for
+ * g_value_init() are defined by a separate interface. See the <link
+ * linkend="gobject-Standard-Parameter-and-Value-Types">Standard
+ * Values API</link> for details.
+ * @title: Generic values
+ *
+ * The #GValue structure is basically a variable container that consists
+ * of a type identifier and a specific value of that type.
+ * The type identifier within a #GValue structure always determines the
+ * type of the associated value.
+ * To create a undefined #GValue structure, simply create a zero-filled
+ * #GValue structure. To initialize the #GValue, use the g_value_init()
+ * function. A #GValue cannot be used until it is initialized.
+ * The basic type operations (such as freeing and copying) are determined
+ * by the #GTypeValueTable associated with the type ID stored in the #GValue.
+ * Other #GValue operations (such as converting values between types) are
+ * provided by this interface.
+ *
+ * The code in the example program below demonstrates #GValue's
+ * features.
+ *
+ * |[
+ * #include <glib-object.h>
+ *
+ * static void
+ * int2string (const GValue *src_value,
+ * GValue *dest_value)
+ * {
+ * if (g_value_get_int (src_value) == 42)
+ * g_value_set_static_string (dest_value, "An important number");
+ * else
+ * g_value_set_static_string (dest_value, "What's that?");
+ * }
+ *
+ * int
+ * main (int argc,
+ * char *argv[])
+ * {
+ * /* GValues must start zero-filled */
+ * GValue a = {0};
+ * GValue b = {0};
+ * const gchar *message;
+ *
+ * g_type_init ();
+ *
+ * /* The GValue starts empty */
+ * g_assert (!G_VALUE_HOLDS_STRING (&a));
+ *
+ * /* Put a string in it */
+ * g_value_init (&a, G_TYPE_STRING);
+ * g_assert (G_VALUE_HOLDS_STRING (&a));
+ * g_value_set_static_string (&a, "Hello, world!");
+ * g_printf ("%s\n", g_value_get_string (&a));
+ *
+ * /* Reset it to its pristine state */
+ * g_value_unset (&a);
+ *
+ * /* It can then be reused for another type */
+ * g_value_init (&a, G_TYPE_INT);
+ * g_value_set_int (&a, 42);
+ *
+ * /* Attempt to transform it into a GValue of type STRING */
+ * g_value_init (&b, G_TYPE_STRING);
+ *
+ * /* An INT is transformable to a STRING */
+ * g_assert (g_value_type_transformable (G_TYPE_INT, G_TYPE_STRING));
+ *
+ * g_value_transform (&a, &b);
+ * g_printf ("%s\n", g_value_get_string (&b));
+ *
+ * /* Attempt to transform it again using a custom transform function */
+ * g_value_register_transform_func (G_TYPE_INT, G_TYPE_STRING, int2string);
+ * g_value_transform (&a, &b);
+ * g_printf ("%s\n", g_value_get_string (&b));
+ * return 0;
+ * }
+ * ]|
+ */
+
+
+/* --- typedefs & structures --- */
+typedef struct {
+ GType src_type;
+ GType dest_type;
+ GValueTransform func;
+} TransformEntry;
+
+
+/* --- prototypes --- */
+static gint transform_entries_cmp (gconstpointer bsearch_node1,
+ gconstpointer bsearch_node2);
+
+
+/* --- variables --- */
+#if EMULATOR
+
+PLS(transform_array,gvalue,GBSearchArray *)
+PLS(transform_bconfig,gvalue,GBSearchConfig )
+
+#define transform_array (*FUNCTION_NAME(transform_array,gvalue)())
+#define transform_bconfig (*FUNCTION_NAME(transform_bconfig ,gvalue)())
+
+const GBSearchConfig temp_transform_bconfig = {
+ sizeof (TransformEntry),
+ transform_entries_cmp,
+ 0,
+};
+
+
+#else
+
+static GBSearchArray *transform_array = NULL;
+static GBSearchConfig transform_bconfig = {
+ sizeof (TransformEntry),
+ transform_entries_cmp,
+ 0,
+};
+
+#endif /* EMULATOR */
+
+
+/* --- functions --- */
+void
+g_value_c_init (void)
+{
+ transform_array = g_bsearch_array_create (&transform_bconfig);
+}
+
+static inline void /* keep this function in sync with gvaluecollector.h and gboxed.c */
+value_meminit (GValue *value,
+ GType value_type)
+{
+ value->g_type = value_type;
+ memset (value->data, 0, sizeof (value->data));
+}
+
+/**
+ * g_value_init:
+ * @value: A zero-filled (uninitialized) #GValue structure.
+ * @g_type: Type the #GValue should hold values of.
+ *
+ * Initializes @value with the default value of @type.
+ *
+ * Returns: the #GValue structure that has been passed in
+ */
+EXPORT_C GValue*
+g_value_init (GValue *value,
+ GType g_type)
+{
+ /* g_return_val_if_fail (G_TYPE_IS_VALUE (g_type), NULL); be more elaborate below */
+ g_return_val_if_fail (value != NULL, NULL);
+ /* g_return_val_if_fail (G_VALUE_TYPE (value) == 0, NULL); be more elaborate below */
+
+ if (G_TYPE_IS_VALUE (g_type) && G_VALUE_TYPE (value) == 0)
+ {
+ GTypeValueTable *value_table = g_type_value_table_peek (g_type);
+
+ /* setup and init */
+ value_meminit (value, g_type);
+ value_table->value_init (value);
+ }
+ else if (G_VALUE_TYPE (value))
+ g_warning ("%s: cannot initialize GValue with type `%s', the value has already been initialized as `%s'",
+ G_STRLOC,
+ g_type_name (g_type),
+ g_type_name (G_VALUE_TYPE (value)));
+ else /* !G_TYPE_IS_VALUE (g_type) */
+ g_warning ("%s: cannot initialize GValue with type `%s', %s",
+ G_STRLOC,
+ g_type_name (g_type),
+ g_type_value_table_peek (g_type) ?
+ "this type is abstract with regards to GValue use, use a more specific (derived) type" :
+ "this type has no GTypeValueTable implementation");
+ return value;
+}
+
+/**
+ * g_value_copy:
+ * @src_value: An initialized #GValue structure.
+ * @dest_value: An initialized #GValue structure of the same type as @src_value.
+ *
+ * Copies the value of @src_value into @dest_value.
+ */
+EXPORT_C void
+g_value_copy (const GValue *src_value,
+ GValue *dest_value)
+{
+ g_return_if_fail (G_IS_VALUE (src_value));
+ g_return_if_fail (G_IS_VALUE (dest_value));
+ g_return_if_fail (g_value_type_compatible (G_VALUE_TYPE (src_value), G_VALUE_TYPE (dest_value)));
+
+ if (src_value != dest_value)
+ {
+ GType dest_type = G_VALUE_TYPE (dest_value);
+ GTypeValueTable *value_table = g_type_value_table_peek (dest_type);
+
+ /* make sure dest_value's value is free()d */
+ if (value_table->value_free)
+ value_table->value_free (dest_value);
+
+ /* setup and copy */
+ value_meminit (dest_value, dest_type);
+ value_table->value_copy (src_value, dest_value);
+ }
+}
+
+/**
+ * g_value_reset:
+ * @value: An initialized #GValue structure.
+ *
+ * Clears the current value in @value and resets it to the default value
+ * (as if the value had just been initialized).
+ *
+ * Returns: the #GValue structure that has been passed in
+ */
+EXPORT_C GValue*
+g_value_reset (GValue *value)
+{
+ GTypeValueTable *value_table;
+ GType g_type;
+
+ g_return_val_if_fail (G_IS_VALUE (value), NULL);
+
+ g_type = G_VALUE_TYPE (value);
+ value_table = g_type_value_table_peek (g_type);
+
+ /* make sure value's value is free()d */
+ if (value_table->value_free)
+ value_table->value_free (value);
+
+ /* setup and init */
+ value_meminit (value, g_type);
+ value_table->value_init (value);
+
+ return value;
+}
+
+/**
+ * g_value_unset:
+ * @value: An initialized #GValue structure.
+ *
+ * Clears the current value in @value and "unsets" the type,
+ * this releases all resources associated with this GValue.
+ * An unset value is the same as an uninitialized (zero-filled)
+ * #GValue structure.
+ */
+EXPORT_C void
+g_value_unset (GValue *value)
+{
+ GTypeValueTable *value_table;
+
+ g_return_if_fail (G_IS_VALUE (value));
+
+ value_table = g_type_value_table_peek (G_VALUE_TYPE (value));
+
+ if (value_table->value_free)
+ value_table->value_free (value);
+ memset (value, 0, sizeof (*value));
+}
+
+/**
+ * g_value_fits_pointer:
+ * @value: An initialized #GValue structure.
+ *
+ * Determines if @value will fit inside the size of a pointer value.
+ * This is an internal function introduced mainly for C marshallers.
+ *
+ * Returns: %TRUE if @value will fit inside a pointer value.
+ */
+EXPORT_C gboolean
+g_value_fits_pointer (const GValue *value)
+{
+ GTypeValueTable *value_table;
+
+ g_return_val_if_fail (G_IS_VALUE (value), FALSE);
+
+ value_table = g_type_value_table_peek (G_VALUE_TYPE (value));
+
+ return value_table->value_peek_pointer != NULL;
+}
+
+/**
+ * g_value_peek_pointer:
+ * @value: An initialized #GValue structure.
+ *
+ * Return the value contents as pointer. This function asserts that
+ * g_value_fits_pointer() returned %TRUE for the passed in value.
+ * This is an internal function introduced mainly for C marshallers.
+ *
+ * Returns: %TRUE if @value will fit inside a pointer value.
+ */
+EXPORT_C gpointer
+g_value_peek_pointer (const GValue *value)
+{
+ GTypeValueTable *value_table;
+
+ g_return_val_if_fail (G_IS_VALUE (value), NULL);
+
+ value_table = g_type_value_table_peek (G_VALUE_TYPE (value));
+ if (!value_table->value_peek_pointer)
+ {
+ g_return_val_if_fail (g_value_fits_pointer (value) == TRUE, NULL);
+ return NULL;
+ }
+
+ return value_table->value_peek_pointer (value);
+}
+
+/**
+ * g_value_set_instance:
+ * @value: An initialized #GValue structure.
+ * @instance: the instance
+ *
+ * Sets @value from an instantiatable type via the
+ * value_table's collect_value() function.
+ */
+EXPORT_C void
+g_value_set_instance (GValue *value,
+ gpointer instance)
+{
+ GType g_type;
+ GTypeValueTable *value_table;
+ GTypeCValue cvalue;
+ gchar *error_msg;
+
+ g_return_if_fail (G_IS_VALUE (value));
+ if (instance)
+ {
+ g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
+ g_return_if_fail (g_value_type_compatible (G_TYPE_FROM_INSTANCE (instance), G_VALUE_TYPE (value)));
+ }
+
+ g_type = G_VALUE_TYPE (value);
+ value_table = g_type_value_table_peek (g_type);
+
+ g_return_if_fail (strcmp (value_table->collect_format, "p") == 0);
+
+ memset (&cvalue, 0, sizeof (cvalue));
+ cvalue.v_pointer = instance;
+
+ /* make sure value's value is free()d */
+ if (value_table->value_free)
+ value_table->value_free (value);
+
+ /* setup and collect */
+ value_meminit (value, g_type);
+ error_msg = value_table->collect_value (value, 1, &cvalue, 0);
+ if (error_msg)
+ {
+ g_warning ("%s: %s", G_STRLOC, error_msg);
+ g_free (error_msg);
+
+ /* we purposely leak the value here, it might not be
+ * in a sane state if an error condition occoured
+ */
+ value_meminit (value, g_type);
+ value_table->value_init (value);
+ }
+}
+
+static GValueTransform
+transform_func_lookup (GType src_type,
+ GType dest_type)
+{
+ TransformEntry entry;
+
+ entry.src_type = src_type;
+ do
+ {
+ entry.dest_type = dest_type;
+ do
+ {
+ TransformEntry *e;
+
+ e = g_bsearch_array_lookup (transform_array, &transform_bconfig, &entry);
+ if (e)
+ {
+ /* need to check that there hasn't been a change in value handling */
+ if (g_type_value_table_peek (entry.dest_type) == g_type_value_table_peek (dest_type) &&
+ g_type_value_table_peek (entry.src_type) == g_type_value_table_peek (src_type))
+ return e->func;
+ }
+ entry.dest_type = g_type_parent (entry.dest_type);
+ }
+ while (entry.dest_type);
+
+ entry.src_type = g_type_parent (entry.src_type);
+ }
+ while (entry.src_type);
+
+ return NULL;
+}
+
+static gint
+transform_entries_cmp (gconstpointer bsearch_node1,
+ gconstpointer bsearch_node2)
+{
+ const TransformEntry *e1 = bsearch_node1;
+ const TransformEntry *e2 = bsearch_node2;
+ gint cmp = G_BSEARCH_ARRAY_CMP (e1->src_type, e2->src_type);
+
+ if (cmp)
+ return cmp;
+ else
+ return G_BSEARCH_ARRAY_CMP (e1->dest_type, e2->dest_type);
+}
+
+/**
+ * g_value_register_transform_func:
+ * @src_type: Source type.
+ * @dest_type: Target type.
+ * @transform_func: a function which transforms values of type @src_type
+ * into value of type @dest_type
+ *
+ * Registers a value transformation function for use in g_value_transform().
+ * A previously registered transformation function for @src_type and @dest_type
+ * will be replaced.
+ */
+EXPORT_C void
+g_value_register_transform_func (GType src_type,
+ GType dest_type,
+ GValueTransform transform_func)
+{
+ TransformEntry entry;
+
+ /* these checks won't pass for dynamic types.
+ * g_return_if_fail (G_TYPE_HAS_VALUE_TABLE (src_type));
+ * g_return_if_fail (G_TYPE_HAS_VALUE_TABLE (dest_type));
+ */
+ g_return_if_fail (transform_func != NULL);
+
+ entry.src_type = src_type;
+ entry.dest_type = dest_type;
+
+#if 0 /* let transform function replacement be a valid operation */
+ if (g_bsearch_array_lookup (transform_array, &transform_bconfig, &entry))
+ g_warning ("reregistering value transformation function (%p) for `%s' to `%s'",
+ transform_func,
+ g_type_name (src_type),
+ g_type_name (dest_type));
+#endif
+
+ entry.func = transform_func;
+ transform_array = g_bsearch_array_replace (transform_array, &transform_bconfig, &entry);
+}
+
+/**
+ * g_value_type_transformable:
+ * @src_type: Source type.
+ * @dest_type: Target type.
+ *
+ * Check whether g_value_transform() is able to transform values
+ * of type @src_type into values of type @dest_type.
+ *
+ * Returns: %TRUE if the transformation is possible, %FALSE otherwise.
+ */
+EXPORT_C gboolean
+g_value_type_transformable (GType src_type,
+ GType dest_type)
+{
+ g_return_val_if_fail (G_TYPE_IS_VALUE (src_type), FALSE);
+ g_return_val_if_fail (G_TYPE_IS_VALUE (dest_type), FALSE);
+
+ return (g_value_type_compatible (src_type, dest_type) ||
+ transform_func_lookup (src_type, dest_type) != NULL);
+}
+
+/**
+ * g_value_type_compatible:
+ * @src_type: source type to be copied.
+ * @dest_type: destination type for copying.
+ *
+ * Returns whether a #GValue of type @src_type can be copied into
+ * a #GValue of type @dest_type.
+ *
+ * Returns: %TRUE if g_value_copy() is possible with @src_type and @dest_type.
+ */
+EXPORT_C gboolean
+g_value_type_compatible (GType src_type,
+ GType dest_type)
+{
+ g_return_val_if_fail (G_TYPE_IS_VALUE (src_type), FALSE);
+ g_return_val_if_fail (G_TYPE_IS_VALUE (dest_type), FALSE);
+
+ return (g_type_is_a (src_type, dest_type) &&
+ g_type_value_table_peek (dest_type) == g_type_value_table_peek (src_type));
+}
+
+/**
+ * g_value_transform:
+ * @src_value: Source value.
+ * @dest_value: Target value.
+ *
+ * Tries to cast the contents of @src_value into a type appropriate
+ * to store in @dest_value, e.g. to transform a %G_TYPE_INT value
+ * into a %G_TYPE_FLOAT value. Performing transformations between
+ * value types might incur precision lossage. Especially
+ * transformations into strings might reveal seemingly arbitrary
+ * results and shouldn't be relied upon for production code (such
+ * as rcfile value or object property serialization).
+ *
+ * Returns: Whether a transformation rule was found and could be applied.
+ * Upon failing transformations, @dest_value is left untouched.
+ */
+EXPORT_C gboolean
+g_value_transform (const GValue *src_value,
+ GValue *dest_value)
+{
+ GType dest_type;
+
+ g_return_val_if_fail (G_IS_VALUE (src_value), FALSE);
+ g_return_val_if_fail (G_IS_VALUE (dest_value), FALSE);
+
+ dest_type = G_VALUE_TYPE (dest_value);
+ if (g_value_type_compatible (G_VALUE_TYPE (src_value), dest_type))
+ {
+ g_value_copy (src_value, dest_value);
+
+ return TRUE;
+ }
+ else
+ {
+ GValueTransform transform = transform_func_lookup (G_VALUE_TYPE (src_value), dest_type);
+
+ if (transform)
+ {
+ g_value_unset (dest_value);
+
+ /* setup and transform */
+ value_meminit (dest_value, dest_type);
+ transform (src_value, dest_value);
+
+ return TRUE;
+ }
+ }
+ return FALSE;
+}
+
+#define __G_VALUE_C__
+#include "gobjectaliasdef.c"