X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftal%2Ftal.h;h=e525a01d1193144168d52c87ab901a1d9cbc655e;hp=0b050759f74ed97829661de5dc2488af74264fe9;hb=9b3f4ef6eec6a5981dcaa62f45da49b8f4f95388;hpb=d6bee61681cf3976c9c0e47e4d73b8ce18f9d7ce

diff --git a/ccan/tal/tal.h b/ccan/tal/tal.h
index 0b050759..e525a01d 100644
--- a/ccan/tal/tal.h
+++ b/ccan/tal/tal.h
@@ -32,7 +32,7 @@ typedef void tal_t;
  *	*p = 1;
  */
 #define tal(ctx, type)							\
-	((type *)tal_alloc_((ctx), sizeof(type), false, TAL_LABEL(type, "")))
+	((type *)tal_alloc_((ctx), sizeof(type), false, false, TAL_LABEL(type, "")))
 
 /**
  * talz - zeroing allocator function
@@ -46,7 +46,7 @@ typedef void tal_t;
  *	assert(*p == 0);
  */
 #define talz(ctx, type)							\
-	((type *)tal_alloc_((ctx), sizeof(type), true, TAL_LABEL(type, "")))
+	((type *)tal_alloc_((ctx), sizeof(type), true, false, TAL_LABEL(type, "")))
 
 /**
  * tal_free - free a tal-allocated pointer.
@@ -56,7 +56,8 @@ typedef void tal_t;
  * children (recursively) before finally freeing the memory.  It returns
  * NULL, for convenience.
  *
- * Note: errno is preserved by this call.
+ * Note: errno is preserved by this call, and also saved and restored
+ * for any destructors or notifiers.
  *
  * Example:
  *	p = tal_free(p);
@@ -168,6 +169,53 @@ void *tal_free(const tal_t *p);
 #define tal_del_destructor(ptr, function)				      \
 	tal_del_destructor_((ptr), typesafe_cb(void, void *, (function), (ptr)))
 
+/**
+ * tal_add_destructor2 - add a 2-arg callback function when context is destroyed.
+ * @ptr: The tal allocated object.
+ * @function: the function to call before it's freed.
+ * @arg: the extra argument to the function.
+ *
+ * Sometimes an extra argument is required for a destructor; this
+ * saves the extra argument internally to avoid the caller having to
+ * do an extra allocation.
+ *
+ * Note that this can only fail if your allocfn fails and your errorfn returns.
+ */
+#define tal_add_destructor2(ptr, function, arg)				\
+	tal_add_destructor2_((ptr),					\
+			     typesafe_cb_cast(void (*)(tal_t *, void *), \
+					      void (*)(__typeof__(ptr), \
+						       __typeof__(arg)), \
+					      (function)),		\
+			     (arg))
+
+/**
+ * tal_del_destructor - remove a destructor callback function.
+ * @ptr: The tal allocated object.
+ * @function: the function to call before it's freed.
+ *
+ * If @function has not been successfully added as a destructor, this returns
+ * false.
+ */
+#define tal_del_destructor(ptr, function)				      \
+	tal_del_destructor_((ptr), typesafe_cb(void, void *, (function), (ptr)))
+
+/**
+ * tal_del_destructor2 - remove 2-arg callback function.
+ * @ptr: The tal allocated object.
+ * @function: the function to call before it's freed.
+ * @arg: the extra argument to the function.
+ *
+ * If @function has not been successfully added as a destructor with
+ * @arg, this returns false.
+ */
+#define tal_del_destructor2(ptr, function, arg)				\
+	tal_del_destructor2_((ptr),					\
+			     typesafe_cb_cast(void (*)(tal_t *, void *), \
+					      void (*)(__typeof__(ptr), \
+						       __typeof__(arg)), \
+					      (function)),		\
+			     (arg))
 enum tal_notify_type {
 	TAL_NOTIFY_FREE = 1,
 	TAL_NOTIFY_STEAL = 2,
@@ -194,6 +242,7 @@ enum tal_notify_type {
  * TAL_NOTIFY_FREE is called when @ptr is freed, either directly or
  * because an ancestor is freed: @info is the argument to tal_free().
  * It is exactly equivalent to a destructor, with more information.
+ * errno is set to the value it was at the call of tal_free().
  *
  * TAL_NOTIFY_STEAL is called when @ptr's parent changes: @info is the
  * new parent.
@@ -232,7 +281,8 @@ enum tal_notify_type {
 	tal_del_notifier_((ptr),					\
 			  typesafe_cb_postargs(void, void *, (callback), \
 					       (ptr),			\
-					       enum tal_notify_type, void *))
+					       enum tal_notify_type, void *), \
+			  false, NULL)
 
 /**
  * tal_set_name - attach a name to a tal pointer.
@@ -254,15 +304,24 @@ const char *tal_name(const tal_t *ptr);
 
 /**
  * tal_count - get the count of objects in a tal_arr.
- * @ptr: The tal allocated object array.
+ * @ptr: The tal allocated object array (or NULL)
+ *
+ * Returns 0 if @ptr has no length property or is NULL, but be aware
+ * that that is also a valid size!
+ */
+#define tal_count(p) (tal_len(p) / sizeof(*p))
+
+/**
+ * tal_len - get the count of bytes in a tal_arr.
+ * @ptr: The tal allocated object array (or NULL)
  *
- * Returns 0 if @ptr has no length property, but we aware that that is
+ * Returns 0 if @ptr has no length property or NULL, but be aware that that is
  * also a valid size!
  */
-size_t tal_count(const tal_t *ptr);
+size_t tal_len(const tal_t *ptr);
 
 /**
- * tal_first - get the first tal object child.
+ * tal_first - get the first immediate tal object child.
  * @root: The tal allocated object to start with, or NULL.
  *
  * Returns NULL if there are no children.
@@ -270,15 +329,13 @@ size_t tal_count(const tal_t *ptr);
 tal_t *tal_first(const tal_t *root);
 
 /**
- * tal_next - get the next tal object child.
- * @root: The tal allocated object to start with, or NULL.
+ * tal_next - get the next immediate tal object child.
  * @prev: The return value from tal_first or tal_next.
  *
- * Returns NULL if there are no more children.  This should be safe to
- * call on an altering tree unless @prev is no longer a descendent of
- * @root.
+ * Returns NULL if there are no more immediate children.  This should be safe to
+ * call on an altering tree unless @prev is no longer valid.
  */
-tal_t *tal_next(const tal_t *root, const tal_t *prev);
+tal_t *tal_next(const tal_t *prev);
 
 /**
  * tal_parent - get the parent of a tal object.
@@ -289,14 +346,25 @@ tal_t *tal_next(const tal_t *root, const tal_t *prev);
 tal_t *tal_parent(const tal_t *ctx);
 
 /**
- * tal_dup - duplicate an array.
+ * 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())
+ */
+#define tal_dup(ctx, type, p)			\
+	((type *)tal_dup_((ctx), tal_typechk_(p, type *),	\
+			  sizeof(type), 1, 0,			\
+			  false, TAL_LABEL(type, "")))
+
+/**
+ * tal_dup_arr - duplicate an 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 array to copy (or resized & reparented if take())
  * @n: the number of sizeof(type) entries to copy.
  * @extra: the number of extra sizeof(type) entries to allocate.
  */
-#define tal_dup(ctx, type, p, n, extra)				\
+#define tal_dup_arr(ctx, type, p, n, extra)			\
 	((type *)tal_dup_((ctx), tal_typechk_(p, type *),	\
 			  sizeof(type), (n), (extra),		\
 			  true, TAL_LABEL(type, "[]")))
@@ -355,13 +423,16 @@ void tal_cleanup(void);
 
 
 /**
- * tal_check - set the allocation or error functions to use
+ * tal_check - sanity check a tal context and its children.
  * @ctx: a tal context, or NULL.
  * @errorstr: a string to prepend calls to error_fn, or NULL.
  *
  * This sanity-checks a tal tree (unless NDEBUG is defined, in which case
  * it simply returns true).  If errorstr is not null, error_fn is called
  * when a problem is found, otherwise it is not.
+ *
+ * See also:
+ *	tal_set_backend()
  */
 bool tal_check(const tal_t *ctx, const char *errorstr);
 
@@ -411,12 +482,13 @@ bool tal_set_name_(tal_t *ctx, const char *name, bool literal);
 #define tal_typechk_(ptr, ptype) (ptr)
 #endif
 
-void *tal_alloc_(const tal_t *ctx, size_t bytes, bool clear, const char *label);
+void *tal_alloc_(const tal_t *ctx, size_t bytes, bool clear,
+		 bool add_length, const char *label);
 void *tal_alloc_arr_(const tal_t *ctx, size_t bytes, size_t count, bool clear,
-		     bool add_count, const char *label);
+		     bool add_length, const char *label);
 
 void *tal_dup_(const tal_t *ctx, const void *p, size_t size,
-	       size_t n, size_t extra, bool add_count,
+	       size_t n, size_t extra, bool add_length,
 	       const char *label);
 
 tal_t *tal_steal_(const tal_t *new_parent, const tal_t *t);
@@ -425,12 +497,17 @@ bool tal_resize_(tal_t **ctxp, size_t size, size_t count, bool clear);
 bool tal_expand_(tal_t **ctxp, const void *src, size_t size, size_t count);
 
 bool tal_add_destructor_(const tal_t *ctx, void (*destroy)(void *me));
+bool tal_add_destructor2_(const tal_t *ctx, void (*destroy)(void *me, void *arg),
+			  void *arg);
 bool tal_del_destructor_(const tal_t *ctx, void (*destroy)(void *me));
+bool tal_del_destructor2_(const tal_t *ctx, void (*destroy)(void *me, void *arg),
+			  void *arg);
 
 bool tal_add_notifier_(const tal_t *ctx, enum tal_notify_type types,
 		       void (*notify)(tal_t *ctx, enum tal_notify_type,
 				      void *info));
 bool tal_del_notifier_(const tal_t *ctx,
 		       void (*notify)(tal_t *ctx, enum tal_notify_type,
-				      void *info));
+				      void *info),
+		       bool match_extra_arg, void *arg);
 #endif /* CCAN_TAL_H */