From 95b709ed55d82adcf3a28876441180321bfb0a48 Mon Sep 17 00:00:00 2001
From: Nicola Fontana <ntd@entidi.it>
Date: Wed, 10 Mar 2010 18:07:10 +0100
Subject: [PATCH] [AdgPoin] Added adg_point_set()

Implemented a convenient function compatible with what requested by the
setters of AdgPoint properties.
---
 adg/adg-point.c | 108 ++++++++++++++++++++++++++++++++++++++------------------
 adg/adg-point.h |   4 ++-
 2 files changed, 76 insertions(+), 36 deletions(-)

diff --git a/adg/adg-point.c b/adg/adg-point.c
index 19f0becb..6dc4d186 100644
--- a/adg/adg-point.c
+++ b/adg/adg-point.c
@@ -67,8 +67,25 @@ adg_point_get_type(void)
 }
 
 /**
+ * adg_point_new:
+ *
+ * Creates a new empty #AdgPoint. The returned pointer
+ * should be freed with adg_point_destroy() when no longer needed.
+ *
+ * The returned value should be freed with adg_point_destroy()
+ * when no longer needed.
+ *
+ * Returns: a newly created #AdgPoint
+ **/
+AdgPoint *
+adg_point_new(void)
+{
+    return g_new0(AdgPoint, 1);
+}
+
+/**
  * adg_point_dup:
- * @src: an #AdgPoint structure
+ * @src: an #AdgPoint
  *
  * Duplicates @src. This operation also adds a new reference
  * to the internal model if @src is linked to a named pair.
@@ -95,40 +112,6 @@ adg_point_dup(const AdgPoint *src)
 }
 
 /**
- * adg_point_new:
- *
- * Creates a new empty #AdgPoint. The returned pointer
- * should be freed with adg_point_destroy() when no longer needed.
- *
- * The returned value should be freed with adg_point_destroy()
- * when no longer needed.
- *
- * Returns: a newly created #AdgPoint
- **/
-AdgPoint *
-adg_point_new(void)
-{
-    return g_new0(AdgPoint, 1);
-}
-
-/**
- * adg_point_destroy:
- * @point: an #AdgPoint
- *
- * Destroys the @point instance, unreferencing the internal model if
- * @point is linked to a named pair.
- **/
-void
-adg_point_destroy(AdgPoint *point)
-{
-    g_return_if_fail(point != NULL);
-
-    adg_point_set_pair_from_model(point, NULL, NULL);
-
-    g_free(point);
-}
-
-/**
  * adg_point_copy:
  * @point: an #AdgPoint
  * @src: the source point to copy
@@ -156,6 +139,61 @@ adg_point_copy(AdgPoint *point, const AdgPoint *src)
 }
 
 /**
+ * adg_point_set:
+ * @p_point: a pointer to an #AdgPoint
+ * @new_point: the new point to assign
+ *
+ * Convenient method to assign @new_point to the #AdgPoint pointed
+ * by @p_point. This is useful while implementing #AdgPoint
+ * property setters.
+ *
+ * At the end *@p_point will be set to @new_point, allocating a new
+ * #AdgPoint or destroying the previous one when necessary. It is
+ * allowed to use %NULL as @new_point to unset *@p_point.
+ *
+ * Returns: %TRUE if the pointer pointed by @p_point has been changed,
+ *          %FALSE otherwise
+ **/
+gboolean
+adg_point_set(AdgPoint **p_point, const AdgPoint *new_point)
+{
+    g_return_val_if_fail(p_point != NULL, FALSE);
+
+    if ((*p_point == new_point) ||
+        (*p_point && new_point && adg_point_equal(*p_point, new_point)))
+        return FALSE;
+
+    if (*p_point == NULL)
+        *p_point = adg_point_new();
+
+    if (new_point) {
+        adg_point_copy(*p_point, new_point);
+    } else {
+        adg_point_destroy(*p_point);
+        *p_point = NULL;
+    }
+
+    return TRUE;
+}
+
+/**
+ * adg_point_destroy:
+ * @point: an #AdgPoint
+ *
+ * Destroys the @point instance, unreferencing the internal model if
+ * @point is linked to a named pair.
+ **/
+void
+adg_point_destroy(AdgPoint *point)
+{
+    g_return_if_fail(point != NULL);
+
+    adg_point_set_pair_from_model(point, NULL, NULL);
+
+    g_free(point);
+}
+
+/**
  * adg_point_set_pair:
  * @point: an #AdgPoint
  * @pair: the #AdgPair to use
diff --git a/adg/adg-point.h b/adg/adg-point.h
index 7fd8ad53..22cd6005 100644
--- a/adg/adg-point.h
+++ b/adg/adg-point.h
@@ -42,9 +42,11 @@ GType           adg_point_get_type              (void) G_GNUC_CONST;
 
 AdgPoint *      adg_point_new                   (void);
 AdgPoint *      adg_point_dup                   (const AdgPoint *src);
-void            adg_point_destroy               (AdgPoint       *point);
 void            adg_point_copy                  (AdgPoint       *point,
                                                  const AdgPoint *src);
+gboolean        adg_point_set                   (AdgPoint      **p_point,
+                                                 const AdgPoint *new_point);
+void            adg_point_destroy               (AdgPoint       *point);
 void            adg_point_set_pair              (AdgPoint       *point,
                                                  const AdgPair  *pair);
 void            adg_point_set_pair_explicit     (AdgPoint       *point,
-- 
2.11.4.GIT