Add generic arrays

2 files changed, 60 insertions, 14 deletions

diff --git a/array.c b/array.c
index c6ea712..945c4d4 100644
--- a/array.c
+++ b/array.c
@@ -138,6 +138,58 @@ array_delete_tail (array_t *array, int n_elements)
     return array;
 }
 
+/* Generic arrays
+ *
+ * The idiomatic way to use them is like this:
+ *
+ *    mytype_t *mytypes = nul_array_new (sizeof (mytype_t));
+ *    mytypes = nul_array_append (mytypes, &a_mytype);
+ *
+ * To iterate through, either use nul_array_len() or rely on
+ * the fact that there will always be at least one element
+ * with nul bits at the end.
+ *
+ */
+
+static const int arr_t_magic;
+
+nul_ptr_t
+nul_array_new (int element_size)
+{
+    return array_new (element_size, &arr_t_magic);
+}
+
+nul_ptr_t
+nul_array_append (nul_ptr_t arr, nul_ptr_t element)
+{
+    array_t *array = get_array (arr, &arr_t_magic);
+    char *data;
+    
+    array = realloc_array (array, array->n_elements + 1);
+
+    data = (char *)array->data;
+
+    data += array->n_elements++ * array->element_size;
+    memcpy (data, element, array->element_size);
+
+    data += array->element_size;
+    memset (data, 0, array->element_size);
+    
+    return arr;
+}
+
+void
+nul_array_free (nul_ptr_t array)
+{
+    array_free (get_array (array, &arr_t_magic));
+}
+
+gsize
+nul_array_len (nul_ptr_t array)
+{
+    return get_array (array, &arr_t_magic)->n_elements;
+}
+
 /* Pointer arrays. The idiomatic way to iterate through such an array is:
  *
  *	void **p;
@@ -163,20 +215,6 @@ array_delete_tail (array_t *array, int n_elements)
  *
  */
 
-typedef struct parr_t parr_t;
-
-static const int parr_t_magic;
-
-struct parr_t
-{
-    const int *magic;
-    gssize n_bytes;		/* Number of bytes allocated in total */
-    gssize n_used;		/* Number of pointers in use, not including
-				 * the final NULL pointer
-				 */
-    void *data[1];
-};
-
 static const int parr_t_magic;
 
 void **
diff --git a/libnul.h b/libnul.h
index 5cef6d1..24e40a4 100644
--- a/libnul.h
+++ b/libnul.h
@@ -50,6 +50,14 @@ typedef void * nul_ptr_t;
 typedef void * const nul_const_ptr_t;
 
 /*
+ * Generic arrays
+ */
+nul_ptr_t  nul_array_new        (int element_size);
+nul_ptr_t  nul_array_append     (nul_ptr_t array, nul_ptr_t element);
+gsize      nul_array_len        (nul_ptr_t array);
+void       nul_array_free       (nul_ptr_t array);
+
+/*
  * Pointer arrays
  */
 nul_ptr_t *nul_ptr_array_new    (void);