Typesafe arrays

6 files changed, 97 insertions, 34 deletions

diff --git a/array.c b/array.c
index f8e9b82..f8341c0 100644
--- a/array.c
+++ b/array.c
@@ -212,31 +212,31 @@ array_len (const void *data, const int *magic)
 static const int arr_t_magic;
 
 nul_ptr_t
-nul_array_new (int element_size)
+nul_garray_new (int element_size)
 {
     return array_new (element_size, &arr_t_magic, 0);
 }
 
 nul_ptr_t
-nul_array_new_prefix (int element_size, int prefix_size)
+nul_garray_new_prefix (int element_size, int prefix_size)
 {
     return array_new (element_size, &arr_t_magic, prefix_size);
 }
 
 nul_ptr_t
-nul_array_append (nul_ptr_t arr, nul_ptr_t element)
+nul_garray_append (nul_ptr_t arr, nul_ptr_t element)
 {
     return array_append (arr, &arr_t_magic, element);
 }
 
 void
-nul_array_free (nul_ptr_t array)
+nul_garray_free (nul_ptr_t array)
 {
     array_free (array, &arr_t_magic);
 }
 
 gsize
-nul_array_len (const nul_ptr_t array)
+nul_garray_len (const nul_ptr_t array)
 {
     return array_len (array, &arr_t_magic);
 }
diff --git a/configure.ac b/configure.ac
index 04d4993..69c997f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -39,6 +39,8 @@ if test "x$GCC" = "xyes"; then
 fi
 
 AC_C_CHAR_UNSIGNED
+AC_C_TYPEOF
+
 
 AC_CONFIG_SUBDIRS(libffi)
 
diff --git a/dbus.c b/dbus.c
index d4a4fdc..7c69d9d 100644
--- a/dbus.c
+++ b/dbus.c
@@ -443,7 +443,7 @@ decode_arg (nul_arg_t **args,
         break;
     }
     
-    *args = nul_array_append (*args, &arg);
+    *args = nul_array_append (*args, arg);
     
     return TRUE;
 }
@@ -495,7 +495,7 @@ fail:
         
         memset (&arg, 0, sizeof (arg));
         
-        *args = nul_array_append (*args, &arg);
+        *args = nul_array_append (*args, arg);
         
         i++;
     }
@@ -553,7 +553,7 @@ invoke (DBusConnection *connection,
 	nul_dbus_member_t      *member,
 	DBusMessage    *message)
 {
-    nul_arg_t *args = nul_array_new (sizeof (nul_arg_t));
+    nul_arg_t *args = nul_array_new (nul_arg_t);
     DBusMessage *error_reply;
     nul_dbus_parameter_t **inputs;
     DBusHandlerResult result;
@@ -569,7 +569,7 @@ invoke (DBusConnection *connection,
 
     arg.v_pointer = object->data;
 
-    args = nul_array_append (args, &arg);
+    args = nul_array_append (args, arg);
 
     inputs = (nul_dbus_parameter_t **)member->parameters;
         
@@ -591,7 +591,7 @@ invoke (DBusConnection *connection,
 
 	g_assert (parameter->out);
         
-        args = nul_array_append (args, &arg);
+        args = nul_array_append (args, arg);
 
         pa = &(args[nul_array_len (args) - 1].v_pointer);
 
@@ -1199,16 +1199,16 @@ on_reply (DBusPendingCall *pending,
     
     outputs = (nul_dbus_parameter_t **)&(info->method->parameters[info->method->n_inputs]);
     
-    args = nul_array_new (sizeof (nul_arg_t));
+    args = nul_array_new (nul_arg_t);
     
     if (!decode_message (&args, reply, n_outputs, outputs, &err))
         arg.v_pointer = err;
     else
         arg.v_pointer = NULL;
-    args = nul_array_append (args, &arg);       /* error */
+    args = nul_array_append (args, arg);       /* error */
     
     arg.v_pointer = info->data;
-    args = nul_array_append (args, &arg);
+    args = nul_array_append (args, arg);
     
     nul_fun_def_invoke (info->method->reply_fun, (nul_function_t)info->callback, args);
     
diff --git a/libnul.h b/libnul.h
index 3bf4106..766ea95 100644
--- a/libnul.h
+++ b/libnul.h
@@ -44,19 +44,36 @@
 #define G_GNUC_WARN_UNUSED_RESULT
 #endif /* __GNUC__ */
 
+#define NUL_COMPILE_TIME_ASSERT(condition,text)				\
+    typedef char nul_error_##text[(condition)? 1 : -1]
+    
 #define NUL_UR G_GNUC_WARN_UNUSED_RESULT
 
 typedef void * nul_ptr_t;
 typedef void * const nul_const_ptr_t;
 
 /*
- * Generic arrays
+ * Generic array implementation
  */
-nul_ptr_t  nul_array_new        (int element_size) NUL_UR;
-nul_ptr_t  nul_array_new_prefix (int element_size, int prefix_size); NUL_UR;
-nul_ptr_t  nul_array_append     (nul_ptr_t array, nul_ptr_t element) NUL_UR;
-gsize      nul_array_len        (nul_ptr_t array);
-void       nul_array_free       (nul_ptr_t array);
+nul_ptr_t  nul_garray_new        (int element_size) NUL_UR;
+nul_ptr_t  nul_garray_new_prefix (int element_size, int prefix_size) NUL_UR;
+nul_ptr_t  nul_garray_append     (nul_ptr_t array, nul_ptr_t element) NUL_UR;
+gsize      nul_garray_len        (nul_ptr_t array);
+void       nul_garray_free       (nul_ptr_t array);
+
+#define nul_array_new(type)		_nul_array_new_impl(type)
+#define nul_array_append(array,value)	_nul_array_append_impl(array,value)
+#define nul_array_len(array)		nul_garray_len(array)
+#define nul_array_free(array)		nul_garray_free(array)
+
+#define nul_prefix_array_new(type,member)				\
+    _nul_prefix_array_new_impl(type,member)
+#define nul_prefix_array_append(array,member,value)			\
+    _nul_prefix_array_append_impl(array,member,value)
+#define nul_prefix_array_len(array,member)				\
+    _nul_prefix_array_len_impl(array,member)
+#define nul_prefix_array_free(array,member)				\
+    _nul_prefix_array_free_impl(array,member)
 
 /*
  * Pointer arrays
@@ -320,4 +337,51 @@ void nul_dbus_invoke (nul_dbus_service_t *service,
 		      gpointer data,
 		      ...);
 
+
+
+/* Implementation of the array macros */
+
+#define _NUL_TYPE_CHECK_ARRAY(array,value)				\
+    NUL_COMPILE_TIME_ASSERT(						\
+	__builtin_types_compatible_p(typeof (*array),typeof(value)),	\
+	incompatible_types						\
+	)
+
+#define _nul_array_new_impl(type)					\
+    ((type *)nul_garray_new(sizeof(type)))
+
+#define _nul_array_append_impl(array,value)				\
+    ((typeof (array))							\
+     nul_garray_append(array, ({					\
+		 typeof (value) __nul_temp = value;			\
+		 _NUL_TYPE_CHECK_ARRAY(array,value);			\
+		 &__nul_temp;						\
+	     })))
+
+#define _nul_prefix_array_new_impl(type,member)				\
+    ((type *)nul_garray_new_prefix(					\
+	 sizeof(((type *)NULL)->member[0]),				\
+	 NUL_STRUCT_OFFSET(type,member)))
+
+#define _nul_prefix_array_append_impl(array,member,value)		\
+    ((typeof (array))							\
+     nul_garray_append(array, ({					\
+		 typeof (value) __nul_temp = (value);			\
+		 _NUL_TYPE_CHECK_ARRAY(&((array)->member)[0], (value));	\
+		 &__nul_temp;						\
+	     })))
+    
+#define _nul_prefix_array_len_impl(array,member)			\
+    ({	(void)((array)->member);					\
+	nul_garray_len(array);						\
+    })
+
+#define _nul_prefix_array_free_impl(array,member)			\
+    ({  (void)((array)->member);					\
+	nul_garray_free(array);						\
+    })
+
+
+
+
 #endif
diff --git a/prefix-test.c b/prefix-test.c
index 5c44562..ca1659d 100644
--- a/prefix-test.c
+++ b/prefix-test.c
@@ -16,25 +16,22 @@ int
 main (void)
 {
     int i;
-    prefixed_t *prefixed = nul_array_new_prefix (
-	sizeof (int), NUL_STRUCT_OFFSET (prefixed_t, data));
-
+    prefixed_t *prefixed = nul_prefix_array_new (prefixed_t, data);
+    int *is = nul_array_new (int);
+    
     prefixed->a = 0xaaaaaaaa;
     prefixed->b = 0xbbbbbbbb;
     prefixed->x = "HI!";
 
-    i = 0;
-    prefixed = nul_array_append (prefixed, &i); i++;
-    prefixed = nul_array_append (prefixed, &i); i++;
-    prefixed = nul_array_append (prefixed, &i); i++;
-    prefixed = nul_array_append (prefixed, &i); i++;
-    prefixed = nul_array_append (prefixed, &i); i++;
-    prefixed = nul_array_append (prefixed, &i); i++;
+    is = nul_array_append (is, i);
+    
+    for (i = 0; i < 128; ++i)
+	prefixed = nul_prefix_array_append (prefixed, data, i);
 
-    for (i = 0; i < nul_array_len (prefixed); ++i)
-    {
+    for (i = 0; i < nul_garray_len (prefixed); ++i)
 	printf ("%d\n", prefixed->data[i]);
-    }
+    
+    printf ("a: %x   b: %x,   c: %s\n", prefixed->a, prefixed->b, prefixed->x);
 
     return 0;
 }
diff --git a/signal-handler.c b/signal-handler.c
index 01cf8c8..fb35c24 100644
--- a/signal-handler.c
+++ b/signal-handler.c
@@ -183,9 +183,9 @@ nul_signal_set_handler (int          signo,
             sigaction (signo, &watch->old_action, NULL);
             
             signal_watch_free (watch);
-
-            return TRUE;
         }
+
+        return TRUE;
     }
     else
     {