exposable: add a "common" constructor and default destructor

particle.c

@@ -1,5 +1,7 @@
 #include "particle.h"
+
 #include <stdlib.h>
+#include <string.h>
 
 void
 particle_default_destroy(struct particle *particle)
@@ -18,3 +20,25 @@ particle_common_new(int left_margin, int right_margin)
     p->deco = NULL;
     return p;
 }
+
+struct exposable *
+exposable_common_new(const struct particle *particle, const char *on_click)
+{
+    struct exposable *exposable = malloc(sizeof(*exposable));
+    exposable->particle = particle;
+    exposable->private = NULL;
+    exposable->width = 0;
+    exposable->on_click = on_click != NULL ? strdup(on_click) : NULL;
+    exposable->destroy = &exposable_default_destroy;
+    exposable->on_mouse = &exposable_default_on_mouse;
+    exposable->begin_expose = NULL;
+    exposable->expose = NULL;
+    return exposable;
+}
+
+void
+exposable_default_destroy(struct exposable *exposable)
+{
+    free(exposable->on_click);
+    free(exposable);
+}

particle.h

@@ -35,3 +35,10 @@ struct exposable {
 
 struct particle *particle_common_new(int left_margin, int right_margin);
 void particle_default_destroy(struct particle *particle);
+
+struct exposable *exposable_common_new(
+    const struct particle *particle, const char *on_click);
+void exposable_default_destroy(struct exposable *exposable);
+void exposable_default_on_mouse(
+    struct exposable *exposable, struct bar *bar,
+    enum mouse_event event, int x, int y);

particles/empty.c

@@ -2,12 +2,6 @@
 
 #include <stdlib.h>
 
-static void
-exposable_destroy(struct exposable *exposable)
-{
-    free(exposable);
-}
-
 static int
 begin_expose(struct exposable *exposable, cairo_t *cr)
 {
@@ -27,9 +21,7 @@ expose(const struct exposable *exposable, cairo_t *cr, int x, int y, int height)
 static struct exposable *
 instantiate(const struct particle *particle, const struct tag_set *tags)
 {
-    struct exposable *exposable = malloc(sizeof(*exposable));
+    struct exposable *exposable = exposable_common_new(particle, NULL);
-    exposable->particle = particle;
-    exposable->destroy = &exposable_destroy;
     exposable->begin_expose = &begin_expose;
     exposable->expose = &expose;
     return exposable;

particles/list.c

@@ -14,6 +14,20 @@ struct exposable_private {
     int left_spacing, right_spacing;
 };
 
+
+static void
+exposable_destroy(struct exposable *exposable)
+{
+    struct exposable_private *e = exposable->private;
+    for (size_t i = 0; i < e->count; i++)
+        e->exposables[i]->destroy(e->exposables[i]);
+
+    free(e->exposables);
+    free(e->widths);
+    free(e);
+    exposable_default_destroy(exposable);
+}
+
 static int
 begin_expose(struct exposable *exposable, cairo_t *cr)
 {
@@ -55,16 +69,8 @@ expose(const struct exposable *exposable, cairo_t *cr, int x, int y, int height)
 }
 
 static void
-exposable_destroy(struct exposable *exposable)
 {
-    struct exposable_private *e = exposable->private;
-    for (size_t i = 0; i < e->count; i++)
-        e->exposables[i]->destroy(e->exposables[i]);
 
-    free(e->exposables);
-    free(e->widths);
-    free(e);
-    free(exposable);
 }
 
 static struct exposable *
@@ -84,9 +90,8 @@ instantiate(const struct particle *particle, const struct tag_set *tags)
         e->exposables[i] = pp->instantiate(pp, tags);
     }
 
-    struct exposable *exposable = malloc(sizeof(*exposable));
+    struct exposable *exposable = exposable_common_new(particle, NULL);
     exposable->private = e;
-    exposable->particle = particle;
     exposable->destroy = &exposable_destroy;
     exposable->begin_expose = &begin_expose;
     exposable->expose = &expose;

particles/progress_bar.c

@@ -48,7 +48,7 @@ exposable_destroy(struct exposable *exposable)
         e->exposables[i]->destroy(e->exposables[i]);
     free(e->exposables);
     free(e);
-    free(exposable);
+    exposable_default_destroy(exposable);
 }
 
 static int
@@ -120,8 +120,7 @@ instantiate(const struct particle *particle, const struct tag_set *tags)
 
     assert(idx == epriv->count);
 
-    struct exposable *exposable = malloc(sizeof(*exposable));
+    struct exposable *exposable = exposable_common_new(particle, NULL);
-    exposable->particle = particle;
     exposable->private = epriv;
     exposable->destroy = &exposable_destroy;
     exposable->begin_expose = &begin_expose;

particles/string.c

@@ -11,6 +11,15 @@ struct private {
     struct rgba foreground;
 };
 
+static void
+exposable_destroy(struct exposable *exposable)
+{
+    struct private *e = exposable->private;
+    free(e->text);
+    free(e);
+    exposable_default_destroy(exposable);
+}
+
 static int
 begin_expose(struct exposable *exposable, cairo_t *cr)
 {
@@ -68,15 +77,6 @@ expose(const struct exposable *exposable, cairo_t *cr, int x, int y, int height)
 
 }
 
-static void
-exposable_destroy(struct exposable *exposable)
-{
-    struct private *e = exposable->private;
-    free(e->text);
-    free(e);
-    free(exposable);
-}
-
 struct sbuf {
     char *s;
     size_t size;
@@ -164,8 +164,7 @@ instantiate(const struct particle *particle, const struct tag_set *tags)
     e->font = p->font;
     e->foreground = p->foreground;
 
-    struct exposable *exposable = malloc(sizeof(*exposable));
+    struct exposable *exposable = exposable_common_new(particle, NULL);
-    exposable->particle = particle;
     exposable->private = e;
     exposable->destroy = &exposable_destroy;
     exposable->begin_expose = &begin_expose;