tal: add tal_dup_or_null and tal_dup_talarr helpers.

[ccan] / ccan / tal / tal.h

diff --git a/ccan/tal/tal.h b/ccan/tal/tal.h
index a3a1549153fe4f42636b116d33162c774982df46..c486f9e8e194a99b51ffdb8117788bbae86a89ed 100644 (file)
--- a/ccan/tal/tal.h
+++ b/ccan/tal/tal.h
@@ -352,10 +352,21 @@ tal_t *tal_parent(const tal_t *ctx);
  * 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.
@@ -369,7 +380,17 @@ tal_t *tal_parent(const tal_t *ctx);
        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))
@@ -379,13 +400,13 @@ tal_t *tal_parent(const tal_t *ctx);
        ((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))
 
 /**
@@ -505,7 +526,9 @@ void *tal_alloc_arr_(const tal_t *ctx, size_t bytes, size_t count, bool clear,
                     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);