Add new code

Signed-off-by: Carlos Maiolino <[email protected]>

1 files changed, 72 insertions, 0 deletions

diff --git a/C/OOP/animal/animal.c b/C/OOP/animal/animal.c
new file mode 100644
index 0000000..01934d7
--- /dev/null
+++ b/C/OOP/animal/animal.c
@@ -0,0 +1,72 @@
+/* Animal class implementation */
+
+#define MAX_NAME_LEN 10
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "animal_priv.h"
+
+
+struct animal * animal_new() {
+	return (struct animal *)malloc(sizeof(struct animal));
+}
+
+/*
+ * By passing the custom sound function to the constructor, we prevent the need to expose the
+ * Animal's private interface to the sub-class
+ *
+ * This is an attempt to get as much abstraction as possible of a C program.
+ * The sub-class has no business in understanding the inner functionality of the parent class,
+ * so, this is an attempt to hide the animal implementation as much as possible from the sub-class.
+ */
+void animal_ctor(struct animal *animal,
+		 void (*sound_fn)(void))
+{
+	animal->name = malloc(MAX_NAME_LEN * sizeof(char));
+
+	if (sound_fn)
+		animal->make_sound = sound_fn;
+	else
+		animal->make_sound = NULL;
+}
+
+void animal_dtor(struct animal *animal)
+{
+	free(animal->name);
+}
+
+void animal_get_name(struct animal *animal, char *name)
+{
+	strncpy(name, animal->name, MAX_NAME_LEN);
+}
+
+void animal_set_name(struct animal *animal, const char *name)
+{
+	if (strlen(name) >= MAX_NAME_LEN)
+		strncpy(animal->name, "\0", 1);
+	else
+		strncpy(animal->name, name, MAX_NAME_LEN);
+}
+
+/*
+ * To be able to access the object specific implementation of make_sound(),
+ * this function should somehow access the function pointer to the
+ * object-specific implementation.
+ *
+ * This could be done in two ways:
+ *	- By having the Animal object embedded within the sub-class, so both
+ *	  the Animal object and the Sub-Class object will share the same address
+ *	  in memory, or:
+ *	- We add an 'ops' field in the Animal object, which should be populated
+ *	  by the sub-class.
+ *
+ *	In both ways, there is no way to really hide the Animal implementation from
+ *	the sub-class, as in one way or another, we'll need to have access to the
+ *	Animal class fields, so we can override the functions.
+ */
+void animal_sound(struct animal *animal)
+{
+	if (animal->make_sound)
+		animal->make_sound();
+}