* This returns true on success (and may move *@p), or false on failure.
* On success, tal_count() of *@p will be @count.
*
+ * Note: if *p is take(), it will still be take() upon return, even if it
+ * has been moved.
+ *
* Example:
* tal_resize(&p, 100);
*/
/**
* tal_steal - change the parent of a tal-allocated pointer.
* @ctx: The new parent.
- * @ptr: The tal allocated object to move.
+ * @ptr: The tal allocated object to move, or NULL.
*
* This may need to perform an allocation, in which case it may fail; thus
- * it can return NULL, otherwise returns @ptr.
+ * it can return NULL, otherwise returns @ptr. If @ptr is NULL, this function does
+ * nothing.
*/
#if HAVE_STATEMENT_EXPR
/* Weird macro avoids gcc's 'warning: value computed is not used'. */
* @function: the function to call before it's freed.
*
* If @function has not been successfully added as a destructor, this returns
- * false.
+ * false. Note that if we're inside the destructor call itself, this will
+ * return false.
*/
#define tal_del_destructor(ptr, function) \
tal_del_destructor_((ptr), typesafe_cb(void, void *, (function), (ptr)))
* @function: the function to call before it's freed.
*
* If @function has not been successfully added as a destructor, this returns
- * false.
+ * false. Note that if we're inside the destructor call itself, this will
+ * return false.
*/
#define tal_del_destructor(ptr, function) \
tal_del_destructor_((ptr), typesafe_cb(void, void *, (function), (ptr)))
/**
* tal_add_notifier - add a callback function when this context changes.
- * @ptr: The tal allocated object.
+ * @ptr: The tal allocated object, or NULL.
* @types: Bitwise OR of the types the callback is interested in.
* @callback: the function to call.
*
* tal_dup - duplicate an object.
* @ctx: The tal allocated object to be parent of the result (may be NULL).
* @type: the type (should match type of @p!)
- * @p: the object to copy (or reparented if take())
+ * @p: the object to copy (or reparented if take()). Must not be NULL.
*/
#define tal_dup(ctx, type, p) \
- tal_dup_label(ctx, type, p, TAL_LABEL(type, ""))
+ tal_dup_label(ctx, type, p, TAL_LABEL(type, ""), false)
+
+/**
+ * tal_dup_or_null - duplicate an object, or just pass NULL.
+ * @ctx: The tal allocated object to be parent of the result (may be NULL).
+ * @type: the type (should match type of @p!)
+ * @p: the object to copy (or reparented if take())
+ *
+ * if @p is NULL, just return NULL, otherwise to tal_dup().
+ */
+#define tal_dup_or_null(ctx, type, p) \
+ tal_dup_label(ctx, type, p, TAL_LABEL(type, ""), true)
/**
* tal_dup_arr - duplicate an array.
tal_dup_arr_label(ctx, type, p, n, extra, TAL_LABEL(type, "[]"))
-
+/**
+ * tal_dup_arr - duplicate a tal array.
+ * @ctx: The tal allocated object to be parent of the result (may be NULL).
+ * @type: the type (should match type of @p!)
+ * @p: the tal array to copy (or resized & reparented if take())
+ *
+ * The comon case of duplicating an entire tal array.
+ */
+#define tal_dup_talarr(ctx, type, p) \
+ ((type *)tal_dup_talarr_((ctx), tal_typechk_(p, type *), \
+ TAL_LABEL(type, "[]")))
/* Lower-level interfaces, where you want to supply your own label string. */
#define tal_label(ctx, type, label) \
((type *)tal_alloc_((ctx), sizeof(type), false, label))
((type *)tal_alloc_arr_((ctx), sizeof(type), (count), false, label))
#define tal_arrz_label(ctx, type, count, label) \
((type *)tal_alloc_arr_((ctx), sizeof(type), (count), true, label))
-#define tal_dup_label(ctx, type, p, label) \
+#define tal_dup_label(ctx, type, p, label, nullok) \
((type *)tal_dup_((ctx), tal_typechk_(p, type *), \
- sizeof(type), 1, 0, \
+ sizeof(type), 1, 0, nullok, \
label))
#define tal_dup_arr_label(ctx, type, p, n, extra, label) \
((type *)tal_dup_((ctx), tal_typechk_(p, type *), \
- sizeof(type), (n), (extra), \
+ sizeof(type), (n), (extra), false, \
label))
/**
#ifdef CCAN_TAL_DEBUG
/**
- * tal_dump - dump entire tal tree.
+ * tal_dump - dump entire tal tree to stderr.
*
* This is a helper for debugging tal itself, which dumps all the tal internal
* state.
const char *label);
void *tal_dup_(const tal_t *ctx, const void *p TAKES, size_t size,
- size_t n, size_t extra, const char *label);
+ size_t n, size_t extra, bool nullok, const char *label);
+void *tal_dup_talarr_(const tal_t *ctx, const tal_t *src TAKES,
+ const char *label);
tal_t *tal_steal_(const tal_t *new_parent, const tal_t *t);