1 /* Licensed under BSD-MIT - see LICENSE file for details */
2 #include <ccan/tal/tal.h>
3 #include <ccan/compiler/compiler.h>
4 #include <ccan/list/list.h>
5 #include <ccan/take/take.h>
6 #include <ccan/alignof/alignof.h>
16 #define NOTIFY_IS_DESTRUCTOR 512
18 /* 32-bit type field, first byte 0 in either endianness. */
20 CHILDREN = 0x00c1d500,
22 NOTIFIER = 0x00071f00,
27 struct list_node list;
28 struct prop_hdr *prop;
29 struct children *parent_child;
34 struct prop_hdr *next;
38 struct prop_hdr hdr; /* CHILDREN */
39 struct tal_hdr *parent;
40 struct list_head children; /* Head of siblings. */
44 struct prop_hdr hdr; /* NAME */
49 struct prop_hdr hdr; /* LENGTH */
54 struct prop_hdr hdr; /* NOTIFIER */
55 enum tal_notify_type types;
57 void (*notifyfn)(tal_t *, enum tal_notify_type, void *);
58 void (*destroy)(tal_t *); /* If NOTIFY_IS_DESTRUCTOR set */
65 } null_parent = { { { &null_parent.hdr.list, &null_parent.hdr.list },
66 &null_parent.c.hdr, NULL },
69 { { &null_parent.c.children.n,
70 &null_parent.c.children.n } }
75 static void *(*allocfn)(size_t size) = malloc;
76 static void *(*resizefn)(void *, size_t size) = realloc;
77 static void (*freefn)(void *) = free;
78 static void (*errorfn)(const char *msg) = (void *)abort;
79 /* Count on non-destrutor notifiers; often stays zero. */
80 static size_t notifiers = 0;
82 static inline void COLD call_error(const char *msg)
87 static bool get_destroying_bit(struct children *parent_child)
89 return (size_t)parent_child & 1;
92 static void set_destroying_bit(struct children **parent_child)
94 *parent_child = (void *)((size_t)*parent_child | 1);
97 static struct children *ignore_destroying_bit(struct children *parent_child)
99 return (void *)((size_t)parent_child & ~(size_t)1);
102 /* This means valgrind can see leaks. */
103 void tal_cleanup(void)
107 while ((i = list_top(&null_parent.c.children, struct tal_hdr, list))) {
109 memset(i, 0, sizeof(*i));
112 /* Cleanup any taken pointers. */
116 /* We carefully start all real properties with a zero byte. */
117 static bool is_literal(const struct prop_hdr *prop)
119 return ((char *)prop)[0] != 0;
123 static const void *bounds_start, *bounds_end;
125 static void update_bounds(const void *new, size_t size)
127 if (unlikely(!bounds_start)) {
129 bounds_end = (char *)new + size;
130 } else if (new < bounds_start)
132 else if ((char *)new + size > (char *)bounds_end)
133 bounds_end = (char *)new + size;
136 static bool in_bounds(const void *p)
139 || (p >= (void *)&null_parent && p <= (void *)(&null_parent + 1))
140 || (p >= bounds_start && p <= bounds_end);
143 static void update_bounds(const void *new, size_t size)
147 static bool in_bounds(const void *p)
153 static void check_bounds(const void *p)
156 call_error("Not a valid header");
159 static struct tal_hdr *to_tal_hdr(const void *ctx)
163 t = (struct tal_hdr *)((char *)ctx - sizeof(struct tal_hdr));
165 check_bounds(ignore_destroying_bit(t->parent_child));
166 check_bounds(t->list.next);
167 check_bounds(t->list.prev);
168 if (t->prop && !is_literal(t->prop))
169 check_bounds(t->prop);
173 static struct tal_hdr *to_tal_hdr_or_null(const void *ctx)
176 return &null_parent.hdr;
177 return to_tal_hdr(ctx);
180 static void *from_tal_hdr(const struct tal_hdr *hdr)
182 return (void *)(hdr + 1);
186 static void *from_tal_hdr_or_null(struct tal_hdr *hdr)
188 if (hdr == &null_parent.hdr)
190 return from_tal_hdr(hdr);
193 static struct tal_hdr *debug_tal(struct tal_hdr *tal)
195 tal_check(from_tal_hdr_or_null(tal), "TAL_DEBUG ");
199 static struct tal_hdr *debug_tal(struct tal_hdr *tal)
205 static void notify(const struct tal_hdr *ctx,
206 enum tal_notify_type type, const void *info)
208 const struct prop_hdr *p;
210 for (p = ctx->prop; p; p = p->next) {
215 if (p->type != NOTIFIER)
217 n = (struct notifier *)p;
218 if (n->types & type) {
219 if (n->types & NOTIFY_IS_DESTRUCTOR)
220 n->u.destroy(from_tal_hdr(ctx));
222 n->u.notifyfn(from_tal_hdr(ctx), type,
228 static void *allocate(size_t size)
230 void *ret = allocfn(size);
232 call_error("allocation failed");
234 update_bounds(ret, size);
238 static struct prop_hdr **find_property_ptr(const struct tal_hdr *t,
243 for (p = (struct prop_hdr **)&t->prop; *p; p = &(*p)->next) {
244 if (is_literal(*p)) {
249 if ((*p)->type == type)
255 static void *find_property(const struct tal_hdr *parent, enum prop_type type)
257 struct prop_hdr **p = find_property_ptr(parent, type);
264 static void init_property(struct prop_hdr *hdr,
265 struct tal_hdr *parent,
269 hdr->next = parent->prop;
273 static struct notifier *add_notifier_property(struct tal_hdr *t,
274 enum tal_notify_type types,
276 enum tal_notify_type,
279 struct notifier *prop = allocate(sizeof(*prop));
281 init_property(&prop->hdr, t, NOTIFIER);
283 prop->u.notifyfn = fn;
288 static enum tal_notify_type del_notifier_property(struct tal_hdr *t,
290 enum tal_notify_type,
295 for (p = (struct prop_hdr **)&t->prop; *p; p = &(*p)->next) {
300 if ((*p)->type != NOTIFIER)
302 n = (struct notifier *)*p;
303 if (n->u.notifyfn == fn) {
304 enum tal_notify_type types = n->types;
307 return types & ~NOTIFY_IS_DESTRUCTOR;
313 static struct name *add_name_property(struct tal_hdr *t, const char *name)
317 prop = allocate(sizeof(*prop) + strlen(name) + 1);
319 init_property(&prop->hdr, t, NAME);
320 strcpy(prop->name, name);
325 static struct children *add_child_property(struct tal_hdr *parent,
326 struct tal_hdr *child UNNEEDED)
328 struct children *prop = allocate(sizeof(*prop));
330 init_property(&prop->hdr, parent, CHILDREN);
331 prop->parent = parent;
332 list_head_init(&prop->children);
337 static bool add_child(struct tal_hdr *parent, struct tal_hdr *child)
339 struct children *children = find_property(parent, CHILDREN);
342 children = add_child_property(parent, child);
346 list_add(&children->children, &child->list);
347 child->parent_child = children;
351 static void del_tree(struct tal_hdr *t, const tal_t *orig)
353 struct prop_hdr **prop, *p, *next;
355 /* Already being destroyed? Don't loop. */
356 if (unlikely(get_destroying_bit(t->parent_child)))
359 set_destroying_bit(&t->parent_child);
361 /* Call free notifiers. */
362 notify(t, TAL_NOTIFY_FREE, (tal_t *)orig);
364 /* Now free children and groups. */
365 prop = find_property_ptr(t, CHILDREN);
368 struct children *c = (struct children *)*prop;
370 while ((i = list_top(&c->children, struct tal_hdr, list))) {
376 /* Finally free our properties. */
377 for (p = t->prop; p && !is_literal(p); p = next) {
379 /* LENGTH is appended, so don't free separately! */
380 if (p->type != LENGTH)
386 static size_t extra_for_length(size_t size)
389 const size_t align = ALIGNOF(struct length);
391 /* Round up size, and add tailer. */
392 extra = ((size + align-1) & ~(align-1)) - size;
393 extra += sizeof(struct length);
397 void *tal_alloc_(const tal_t *ctx, size_t size,
398 bool clear, bool add_length, const char *label)
400 size_t req_size = size;
401 struct tal_hdr *child, *parent = debug_tal(to_tal_hdr_or_null(ctx));
403 #ifdef CCAN_TAL_DEBUG
404 /* Always record length if debugging. */
408 size += extra_for_length(size);
410 child = allocate(sizeof(struct tal_hdr) + size);
414 memset(from_tal_hdr(child), 0, req_size);
415 child->prop = (void *)label;
418 struct length *lprop;
419 lprop = (struct length *)((char *)(child+1) + size) - 1;
420 init_property(&lprop->hdr, child, LENGTH);
421 lprop->len = req_size;
423 if (!add_child(parent, child)) {
429 notify(parent, TAL_NOTIFY_ADD_CHILD, from_tal_hdr(child));
430 return from_tal_hdr(debug_tal(child));
433 static bool adjust_size(size_t *size, size_t count)
435 const size_t extra = sizeof(struct tal_hdr) + sizeof(struct length)*2;
437 /* Multiplication wrap */
438 if (count && unlikely(*size * count / *size != count))
443 /* Make sure we don't wrap adding header/tailer. */
444 if (*size + extra < extra)
448 call_error("allocation size overflow");
452 void *tal_alloc_arr_(const tal_t *ctx, size_t size, size_t count, bool clear,
453 bool add_length, const char *label)
455 if (!adjust_size(&size, count))
458 return tal_alloc_(ctx, size, clear, add_length, label);
461 void *tal_free(const tal_t *ctx)
465 int saved_errno = errno;
466 t = debug_tal(to_tal_hdr(ctx));
468 notify(ignore_destroying_bit(t->parent_child)->parent,
469 TAL_NOTIFY_DEL_CHILD, ctx);
477 void *tal_steal_(const tal_t *new_parent, const tal_t *ctx)
480 struct tal_hdr *newpar, *t, *old_parent;
482 newpar = debug_tal(to_tal_hdr_or_null(new_parent));
483 t = debug_tal(to_tal_hdr(ctx));
485 /* Unlink it from old parent. */
487 old_parent = ignore_destroying_bit(t->parent_child)->parent;
489 if (unlikely(!add_child(newpar, t))) {
490 /* We can always add to old parent, becuase it has a
491 * children property already. */
492 if (!add_child(old_parent, t))
498 notify(t, TAL_NOTIFY_STEAL, new_parent);
503 bool tal_add_destructor_(const tal_t *ctx, void (*destroy)(void *me))
505 tal_t *t = debug_tal(to_tal_hdr(ctx));
506 return add_notifier_property(t, TAL_NOTIFY_FREE|NOTIFY_IS_DESTRUCTOR,
510 bool tal_add_notifier_(const tal_t *ctx, enum tal_notify_type types,
511 void (*callback)(tal_t *, enum tal_notify_type, void *))
513 tal_t *t = debug_tal(to_tal_hdr(ctx));
517 assert((types & ~(TAL_NOTIFY_FREE | TAL_NOTIFY_STEAL | TAL_NOTIFY_MOVE
518 | TAL_NOTIFY_RESIZE | TAL_NOTIFY_RENAME
519 | TAL_NOTIFY_ADD_CHILD | TAL_NOTIFY_DEL_CHILD
520 | TAL_NOTIFY_ADD_NOTIFIER
521 | TAL_NOTIFY_DEL_NOTIFIER)) == 0);
523 /* Don't call notifier about itself: set types after! */
524 n = add_notifier_property(t, 0, callback);
529 notify(t, TAL_NOTIFY_ADD_NOTIFIER, callback);
532 if (types != TAL_NOTIFY_FREE)
537 bool tal_del_notifier_(const tal_t *ctx,
538 void (*callback)(tal_t *, enum tal_notify_type, void *))
540 struct tal_hdr *t = debug_tal(to_tal_hdr(ctx));
541 enum tal_notify_type types;
543 types = del_notifier_property(t, callback);
545 notify(t, TAL_NOTIFY_DEL_NOTIFIER, callback);
546 if (types != TAL_NOTIFY_FREE)
553 bool tal_del_destructor_(const tal_t *ctx, void (*destroy)(void *me))
555 return tal_del_notifier_(ctx, (void *)destroy);
558 bool tal_set_name_(tal_t *ctx, const char *name, bool literal)
560 struct tal_hdr *t = debug_tal(to_tal_hdr(ctx));
561 struct prop_hdr **prop = find_property_ptr(t, NAME);
563 /* Get rid of any old name */
565 struct name *name = (struct name *)*prop;
566 if (is_literal(&name->hdr))
569 *prop = name->hdr.next;
574 if (literal && name[0]) {
577 /* Append literal. */
578 for (p = &t->prop; *p && !is_literal(*p); p = &(*p)->next);
579 *p = (struct prop_hdr *)name;
580 } else if (!add_name_property(t, name))
585 notify(t, TAL_NOTIFY_RENAME, name);
589 const char *tal_name(const tal_t *t)
593 n = find_property(debug_tal(to_tal_hdr(t)), NAME);
597 if (is_literal(&n->hdr))
598 return (const char *)n;
602 size_t tal_len(const tal_t *ptr)
606 l = find_property(debug_tal(to_tal_hdr(ptr)), LENGTH);
612 /* Start one past first child: make stopping natural in circ. list. */
613 static struct tal_hdr *first_child(struct tal_hdr *parent)
615 struct children *child;
617 child = find_property(parent, CHILDREN);
621 return list_top(&child->children, struct tal_hdr, list);
624 tal_t *tal_first(const tal_t *root)
626 struct tal_hdr *c, *t = debug_tal(to_tal_hdr_or_null(root));
631 return from_tal_hdr(c);
634 tal_t *tal_next(const tal_t *prev)
636 struct tal_hdr *next, *prevhdr = debug_tal(to_tal_hdr(prev));
637 struct list_head *head;
639 head = &ignore_destroying_bit(prevhdr->parent_child)->children;
640 next = list_next(head, prevhdr, list);
643 return from_tal_hdr(next);
646 tal_t *tal_parent(const tal_t *ctx)
653 t = debug_tal(to_tal_hdr(ctx));
654 if (ignore_destroying_bit(t->parent_child)->parent == &null_parent.hdr)
656 return from_tal_hdr(ignore_destroying_bit(t->parent_child)->parent);
659 bool tal_resize_(tal_t **ctxp, size_t size, size_t count, bool clear)
661 struct tal_hdr *old_t, *t;
662 struct children *child;
663 struct prop_hdr **lenp;
667 old_t = debug_tal(to_tal_hdr(*ctxp));
669 if (!adjust_size(&size, count))
672 lenp = find_property_ptr(old_t, LENGTH);
674 /* Copy here, in case we're shrinking! */
675 len = *(struct length *)*lenp;
676 extra = extra_for_length(size);
677 } else /* If we don't have an old length, we can't clear! */
680 t = resizefn(old_t, sizeof(struct tal_hdr) + size + extra);
682 call_error("Reallocation failure");
686 /* Copy length to end. */
688 struct length *new_len;
690 /* Clear between old end and new end. */
691 if (clear && size > len.len) {
692 char *old_end = (char *)(t + 1) + len.len;
693 memset(old_end, 0, size - len.len);
696 new_len = (struct length *)((char *)(t + 1) + size
697 + extra - sizeof(len));
701 /* Be careful replacing next ptr; could be old hdr. */
702 if (lenp == &old_t->prop)
703 t->prop = &new_len->hdr;
705 *lenp = &new_len->hdr;
708 update_bounds(t, sizeof(struct tal_hdr) + size + extra);
710 /* If it didn't move, we're done! */
712 /* Fix up linked list pointers. */
713 t->list.next->prev = t->list.prev->next = &t->list;
715 /* Fix up child property's parent pointer. */
716 child = find_property(t, CHILDREN);
718 assert(child->parent == old_t);
721 *ctxp = from_tal_hdr(debug_tal(t));
723 notify(t, TAL_NOTIFY_MOVE, from_tal_hdr(old_t));
726 notify(t, TAL_NOTIFY_RESIZE, (void *)size);
731 bool tal_expand_(tal_t **ctxp, const void *src, size_t size, size_t count)
737 l = find_property(debug_tal(to_tal_hdr(*ctxp)), LENGTH);
740 /* Check for additive overflow */
741 if (old_len + count * size < old_len) {
742 call_error("dup size overflow");
746 /* Don't point src inside thing we're expanding! */
748 || (char *)src >= (char *)(*ctxp) + old_len);
750 if (!tal_resize_(ctxp, size, old_len/size + count, false))
753 memcpy((char *)*ctxp + old_len, src, count * size);
762 void *tal_dup_(const tal_t *ctx, const void *p, size_t size,
763 size_t n, size_t extra, bool add_length,
767 size_t nbytes = size;
769 if (!adjust_size(&nbytes, n)) {
775 /* Beware addition overflow! */
777 call_error("dup size overflow");
786 if (unlikely(!tal_resize_((void **)&p, size, n + extra, false)))
788 if (unlikely(!tal_steal(ctx, p)))
793 ret = tal_alloc_arr_(ctx, size, n + extra, false, add_length, label);
795 memcpy(ret, p, nbytes);
799 void tal_set_backend(void *(*alloc_fn)(size_t size),
800 void *(*resize_fn)(void *, size_t size),
801 void (*free_fn)(void *),
802 void (*error_fn)(const char *msg))
807 resizefn = resize_fn;
814 #ifdef CCAN_TAL_DEBUG
815 static void dump_node(unsigned int indent, const struct tal_hdr *t)
818 const struct prop_hdr *p;
820 for (i = 0; i < indent; i++)
823 for (p = t->prop; p; p = p->next) {
829 printf(" \"%s\"", (const char *)p);
834 c = (struct children *)p;
835 printf(" CHILDREN(%p):parent=%p,children={%p,%p}\n",
837 c->children.n.prev, c->children.n.next);
840 n = (struct name *)p;
841 printf(" NAME(%p):%s", p, n->name);
844 no = (struct notifier *)p;
845 printf(" NOTIFIER(%p):fn=%p", p, no->u.notifyfn);
848 l = (struct length *)p;
849 printf(" LENGTH(%p):len=%zu", p, l->len);
852 printf(" **UNKNOWN(%p):%i**", p, p->type);
858 static void tal_dump_(unsigned int level, const struct tal_hdr *t)
860 struct children *children;
864 children = find_property(t, CHILDREN);
868 list_for_each(&children->children, i, list)
869 tal_dump_(level + 1, i);
875 tal_dump_(0, &null_parent.hdr);
877 #endif /* CCAN_TAL_DEBUG */
880 static bool check_err(struct tal_hdr *t, const char *errorstr,
884 /* Try not to malloc: it may be corrupted. */
885 char msg[strlen(errorstr) + 20 + strlen(errmsg) + 1];
886 sprintf(msg, "%s:%p %s", errorstr, from_tal_hdr(t), errmsg);
892 static bool check_node(struct children *parent_child,
893 struct tal_hdr *t, const char *errorstr)
896 struct name *name = NULL;
897 struct children *children = NULL;
898 struct length *length = NULL;
901 return check_err(t, errorstr, "invalid pointer");
903 if (ignore_destroying_bit(t->parent_child) != parent_child)
904 return check_err(t, errorstr, "incorrect parent");
906 for (p = t->prop; p; p = p->next) {
909 return check_err(t, errorstr,
910 "has extra literal");
914 return check_err(t, errorstr,
915 "has bad property pointer");
920 return check_err(t, errorstr,
921 "has two child nodes");
922 children = (struct children *)p;
926 return check_err(t, errorstr,
928 length = (struct length *)p;
934 return check_err(t, errorstr,
936 name = (struct name *)p;
939 return check_err(t, errorstr, "has unknown property");
945 if (!list_check(&children->children, errorstr))
947 list_for_each(&children->children, i, list) {
948 if (!check_node(children, i, errorstr))
955 bool tal_check(const tal_t *ctx, const char *errorstr)
957 struct tal_hdr *t = to_tal_hdr_or_null(ctx);
959 return check_node(ignore_destroying_bit(t->parent_child), t, errorstr);
962 bool tal_check(const tal_t *ctx, const char *errorstr)