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)
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 void *tal_alloc_(const tal_t *ctx, size_t size, bool clear, const char *label)
388 struct tal_hdr *child, *parent = debug_tal(to_tal_hdr_or_null(ctx));
390 child = allocate(sizeof(struct tal_hdr) + size);
394 memset(from_tal_hdr(child), 0, size);
395 child->prop = (void *)label;
396 if (!add_child(parent, child)) {
402 notify(parent, TAL_NOTIFY_ADD_CHILD, from_tal_hdr(child));
403 return from_tal_hdr(debug_tal(child));
406 static bool adjust_size(size_t *size, size_t count)
408 const size_t extra = sizeof(struct tal_hdr) + sizeof(struct length)*2;
410 /* Multiplication wrap */
411 if (count && unlikely(*size * count / *size != count))
416 /* Make sure we don't wrap adding header/tailer. */
417 if (*size + extra < extra)
421 call_error("allocation size overflow");
425 static size_t extra_for_length(size_t size)
428 const size_t align = ALIGNOF(struct length);
430 /* Round up size, and add tailer. */
431 extra = ((size + align-1) & ~(align-1)) - size;
432 extra += sizeof(struct length);
436 void *tal_alloc_arr_(const tal_t *ctx, size_t size, size_t count, bool clear,
437 bool add_count, const char *label)
441 if (!adjust_size(&size, count))
445 size += extra_for_length(size);
447 ret = tal_alloc_(ctx, size, clear, label);
452 struct length *lprop;
453 lprop = (struct length *)((char *)ret + size) - 1;
454 init_property(&lprop->hdr, to_tal_hdr(ret), LENGTH);
455 lprop->count = count;
460 void *tal_free(const tal_t *ctx)
464 int saved_errno = errno;
465 t = debug_tal(to_tal_hdr(ctx));
467 notify(ignore_destroying_bit(t->parent_child)->parent,
468 TAL_NOTIFY_DEL_CHILD, ctx);
476 void *tal_steal_(const tal_t *new_parent, const tal_t *ctx)
479 struct tal_hdr *newpar, *t, *old_parent;
481 newpar = debug_tal(to_tal_hdr_or_null(new_parent));
482 t = debug_tal(to_tal_hdr(ctx));
484 /* Unlink it from old parent. */
486 old_parent = ignore_destroying_bit(t->parent_child)->parent;
488 if (unlikely(!add_child(newpar, t))) {
489 /* We can always add to old parent, becuase it has a
490 * children property already. */
491 if (!add_child(old_parent, t))
497 notify(t, TAL_NOTIFY_STEAL, new_parent);
502 bool tal_add_destructor_(const tal_t *ctx, void (*destroy)(void *me))
504 tal_t *t = debug_tal(to_tal_hdr(ctx));
505 return add_notifier_property(t, TAL_NOTIFY_FREE|NOTIFY_IS_DESTRUCTOR,
509 bool tal_add_notifier_(const tal_t *ctx, enum tal_notify_type types,
510 void (*callback)(tal_t *, enum tal_notify_type, void *))
512 tal_t *t = debug_tal(to_tal_hdr(ctx));
516 assert((types & ~(TAL_NOTIFY_FREE | TAL_NOTIFY_STEAL | TAL_NOTIFY_MOVE
517 | TAL_NOTIFY_RESIZE | TAL_NOTIFY_RENAME
518 | TAL_NOTIFY_ADD_CHILD | TAL_NOTIFY_DEL_CHILD
519 | TAL_NOTIFY_ADD_NOTIFIER
520 | TAL_NOTIFY_DEL_NOTIFIER)) == 0);
522 /* Don't call notifier about itself: set types after! */
523 n = add_notifier_property(t, 0, callback);
528 notify(t, TAL_NOTIFY_ADD_NOTIFIER, callback);
531 if (types != TAL_NOTIFY_FREE)
536 bool tal_del_notifier_(const tal_t *ctx,
537 void (*callback)(tal_t *, enum tal_notify_type, void *))
539 struct tal_hdr *t = debug_tal(to_tal_hdr(ctx));
540 enum tal_notify_type types;
542 types = del_notifier_property(t, callback);
544 notify(t, TAL_NOTIFY_DEL_NOTIFIER, callback);
545 if (types != TAL_NOTIFY_FREE)
552 bool tal_del_destructor_(const tal_t *ctx, void (*destroy)(void *me))
554 return tal_del_notifier_(ctx, (void *)destroy);
557 bool tal_set_name_(tal_t *ctx, const char *name, bool literal)
559 struct tal_hdr *t = debug_tal(to_tal_hdr(ctx));
560 struct prop_hdr **prop = find_property_ptr(t, NAME);
562 /* Get rid of any old name */
564 struct name *name = (struct name *)*prop;
565 if (is_literal(&name->hdr))
568 *prop = name->hdr.next;
573 if (literal && name[0]) {
576 /* Append literal. */
577 for (p = &t->prop; *p && !is_literal(*p); p = &(*p)->next);
578 *p = (struct prop_hdr *)name;
579 } else if (!add_name_property(t, name))
584 notify(t, TAL_NOTIFY_RENAME, name);
588 const char *tal_name(const tal_t *t)
592 n = find_property(debug_tal(to_tal_hdr(t)), NAME);
596 if (is_literal(&n->hdr))
597 return (const char *)n;
601 size_t tal_count(const tal_t *ptr)
605 l = find_property(debug_tal(to_tal_hdr(ptr)), LENGTH);
611 /* Start one past first child: make stopping natural in circ. list. */
612 static struct tal_hdr *first_child(struct tal_hdr *parent)
614 struct children *child;
616 child = find_property(parent, CHILDREN);
620 return list_top(&child->children, struct tal_hdr, list);
623 tal_t *tal_first(const tal_t *root)
625 struct tal_hdr *c, *t = debug_tal(to_tal_hdr_or_null(root));
630 return from_tal_hdr(c);
633 tal_t *tal_next(const tal_t *root, const tal_t *prev)
635 struct tal_hdr *c, *t = debug_tal(to_tal_hdr(prev)), *top;
640 return from_tal_hdr(c);
642 top = to_tal_hdr_or_null(root);
644 struct tal_hdr *next;
645 struct list_node *end;
647 end = &ignore_destroying_bit(t->parent_child)->children.n;
649 next = list_entry(t->list.next, struct tal_hdr, list);
650 if (&next->list != end)
651 return from_tal_hdr(next);
653 /* OK, go back to parent. */
654 t = ignore_destroying_bit(t->parent_child)->parent;
660 tal_t *tal_parent(const tal_t *ctx)
667 t = debug_tal(to_tal_hdr(ctx));
668 if (ignore_destroying_bit(t->parent_child)->parent == &null_parent.hdr)
670 return from_tal_hdr(ignore_destroying_bit(t->parent_child)->parent);
673 bool tal_resize_(tal_t **ctxp, size_t size, size_t count, bool clear)
675 struct tal_hdr *old_t, *t;
676 struct children *child;
677 struct prop_hdr **lenp;
679 size_t extra = 0, elemsize = size;
681 old_t = debug_tal(to_tal_hdr(*ctxp));
683 if (!adjust_size(&size, count))
686 lenp = find_property_ptr(old_t, LENGTH);
688 /* Copy here, in case we're shrinking! */
689 len = *(struct length *)*lenp;
690 extra = extra_for_length(size);
691 } else /* If we don't have an old length, we can't clear! */
694 t = resizefn(old_t, sizeof(struct tal_hdr) + size + extra);
696 call_error("Reallocation failure");
700 /* Copy length to end. */
702 struct length *new_len;
704 /* Clear between old end and new end. */
705 if (clear && count > len.count) {
706 char *old_end = (char *)(t + 1) + len.count * elemsize;
707 memset(old_end, 0, elemsize * (count - len.count));
710 new_len = (struct length *)((char *)(t + 1) + size);
714 /* Be careful replacing next ptr; could be old hdr. */
715 if (lenp == &old_t->prop)
716 t->prop = &new_len->hdr;
718 *lenp = &new_len->hdr;
721 update_bounds(t, sizeof(struct tal_hdr) + size + extra);
723 /* If it didn't move, we're done! */
725 /* Fix up linked list pointers. */
726 t->list.next->prev = t->list.prev->next = &t->list;
728 /* Fix up child property's parent pointer. */
729 child = find_property(t, CHILDREN);
731 assert(child->parent == old_t);
734 *ctxp = from_tal_hdr(debug_tal(t));
736 notify(t, TAL_NOTIFY_MOVE, from_tal_hdr(old_t));
739 notify(t, TAL_NOTIFY_RESIZE, (void *)size);
744 bool tal_expand_(tal_t **ctxp, const void *src, size_t size, size_t count)
750 l = find_property(debug_tal(to_tal_hdr(*ctxp)), LENGTH);
751 old_count = l->count;
753 /* Check for additive overflow */
754 if (old_count + count < count) {
755 call_error("dup size overflow");
759 /* Don't point src inside thing we're expanding! */
761 || (char *)src >= (char *)(*ctxp) + (size * old_count));
763 if (!tal_resize_(ctxp, size, old_count + count, false))
766 memcpy((char *)*ctxp + size * old_count, src, count * size);
775 void *tal_dup_(const tal_t *ctx, const void *p, size_t size,
776 size_t n, size_t extra, bool add_count,
780 size_t nbytes = size;
782 if (!adjust_size(&nbytes, n)) {
788 /* Beware addition overflow! */
790 call_error("dup size overflow");
799 if (unlikely(!tal_resize_((void **)&p, size, n + extra, false)))
801 if (unlikely(!tal_steal(ctx, p)))
806 ret = tal_alloc_arr_(ctx, size, n + extra, false, add_count, label);
808 memcpy(ret, p, nbytes);
812 void tal_set_backend(void *(*alloc_fn)(size_t size),
813 void *(*resize_fn)(void *, size_t size),
814 void (*free_fn)(void *),
815 void (*error_fn)(const char *msg))
820 resizefn = resize_fn;
827 #ifdef CCAN_TAL_DEBUG
828 static void dump_node(unsigned int indent, const struct tal_hdr *t)
831 const struct prop_hdr *p;
833 for (i = 0; i < indent; i++)
836 for (p = t->prop; p; p = p->next) {
842 printf(" \"%s\"", (const char *)p);
847 c = (struct children *)p;
848 printf(" CHILDREN(%p):parent=%p,children={%p,%p}\n",
850 c->children.n.prev, c->children.n.next);
853 n = (struct name *)p;
854 printf(" NAME(%p):%s", p, n->name);
857 no = (struct notifier *)p;
858 printf(" NOTIFIER(%p):fn=%p", p, no->u.notifyfn);
861 l = (struct length *)p;
862 printf(" LENGTH(%p):count=%zu", p, l->count);
865 printf(" **UNKNOWN(%p):%i**", p, p->type);
871 static void tal_dump_(unsigned int level, const struct tal_hdr *t)
873 struct children *children;
877 children = find_property(t, CHILDREN);
881 list_for_each(&children->children, i, list)
882 tal_dump_(level + 1, i);
888 tal_dump_(0, &null_parent.hdr);
890 #endif /* CCAN_TAL_DEBUG */
893 static bool check_err(struct tal_hdr *t, const char *errorstr,
897 /* Try not to malloc: it may be corrupted. */
898 char msg[strlen(errorstr) + 20 + strlen(errmsg) + 1];
899 sprintf(msg, "%s:%p %s", errorstr, from_tal_hdr(t), errmsg);
905 static bool check_node(struct children *parent_child,
906 struct tal_hdr *t, const char *errorstr)
909 struct name *name = NULL;
910 struct children *children = NULL;
911 struct length *length = NULL;
914 return check_err(t, errorstr, "invalid pointer");
916 if (ignore_destroying_bit(t->parent_child) != parent_child)
917 return check_err(t, errorstr, "incorrect parent");
919 for (p = t->prop; p; p = p->next) {
922 return check_err(t, errorstr,
923 "has extra literal");
924 name = (struct name *)p;
928 return check_err(t, errorstr,
929 "has bad property pointer");
934 return check_err(t, errorstr,
935 "has two child nodes");
936 children = (struct children *)p;
940 return check_err(t, errorstr,
942 length = (struct length *)p;
948 return check_err(t, errorstr,
950 name = (struct name *)p;
953 return check_err(t, errorstr, "has unknown property");
959 if (!list_check(&children->children, errorstr))
961 list_for_each(&children->children, i, list) {
962 if (!check_node(children, i, errorstr))
969 bool tal_check(const tal_t *ctx, const char *errorstr)
971 struct tal_hdr *t = to_tal_hdr_or_null(ctx);
973 return check_node(ignore_destroying_bit(t->parent_child), t, errorstr);
976 bool tal_check(const tal_t *ctx, const char *errorstr)