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/alignof/alignof.h>
15 #define NOTIFY_IS_DESTRUCTOR 512
16 #define NOTIFY_EXTRA_ARG 1024
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 */
59 void (*destroy2)(tal_t *, void *); /* If NOTIFY_EXTRA_ARG */
64 struct notifier_extra_arg {
69 #define EXTRA_ARG(n) (((struct notifier_extra_arg *)(n))->arg)
74 } null_parent = { { { &null_parent.hdr.list, &null_parent.hdr.list },
75 &null_parent.c.hdr, NULL },
78 { { &null_parent.c.children.n,
79 &null_parent.c.children.n } }
84 static void *(*allocfn)(size_t size) = malloc;
85 static void *(*resizefn)(void *, size_t size) = realloc;
86 static void (*freefn)(void *) = free;
87 static void (*errorfn)(const char *msg) = (void *)abort;
88 /* Count on non-destrutor notifiers; often stays zero. */
89 static size_t notifiers = 0;
91 static inline void COLD call_error(const char *msg)
96 static bool get_destroying_bit(struct children *parent_child)
98 return (size_t)parent_child & 1;
101 static void set_destroying_bit(struct children **parent_child)
103 *parent_child = (void *)((size_t)*parent_child | 1);
106 static struct children *ignore_destroying_bit(struct children *parent_child)
108 return (void *)((size_t)parent_child & ~(size_t)1);
111 /* This means valgrind can see leaks. */
112 void tal_cleanup(void)
116 while ((i = list_top(&null_parent.c.children, struct tal_hdr, list))) {
118 memset(i, 0, sizeof(*i));
121 /* Cleanup any taken pointers. */
125 /* We carefully start all real properties with a zero byte. */
126 static bool is_literal(const struct prop_hdr *prop)
128 return ((char *)prop)[0] != 0;
132 static const void *bounds_start, *bounds_end;
134 static void update_bounds(const void *new, size_t size)
136 if (unlikely(!bounds_start)) {
138 bounds_end = (char *)new + size;
139 } else if (new < bounds_start)
141 else if ((char *)new + size > (char *)bounds_end)
142 bounds_end = (char *)new + size;
145 static bool in_bounds(const void *p)
148 || (p >= (void *)&null_parent && p <= (void *)(&null_parent + 1))
149 || (p >= bounds_start && p <= bounds_end);
152 static void update_bounds(const void *new, size_t size)
156 static bool in_bounds(const void *p)
162 static void check_bounds(const void *p)
165 call_error("Not a valid header");
168 static struct tal_hdr *to_tal_hdr(const void *ctx)
172 t = (struct tal_hdr *)((char *)ctx - sizeof(struct tal_hdr));
174 check_bounds(ignore_destroying_bit(t->parent_child));
175 check_bounds(t->list.next);
176 check_bounds(t->list.prev);
177 if (t->prop && !is_literal(t->prop))
178 check_bounds(t->prop);
182 static struct tal_hdr *to_tal_hdr_or_null(const void *ctx)
185 return &null_parent.hdr;
186 return to_tal_hdr(ctx);
189 static void *from_tal_hdr(const struct tal_hdr *hdr)
191 return (void *)(hdr + 1);
195 static void *from_tal_hdr_or_null(struct tal_hdr *hdr)
197 if (hdr == &null_parent.hdr)
199 return from_tal_hdr(hdr);
202 static struct tal_hdr *debug_tal(struct tal_hdr *tal)
204 tal_check(from_tal_hdr_or_null(tal), "TAL_DEBUG ");
208 static struct tal_hdr *debug_tal(struct tal_hdr *tal)
214 static void notify(const struct tal_hdr *ctx,
215 enum tal_notify_type type, const void *info,
218 const struct prop_hdr *p;
220 for (p = ctx->prop; p; p = p->next) {
225 if (p->type != NOTIFIER)
227 n = (struct notifier *)p;
228 if (n->types & type) {
230 if (n->types & NOTIFY_IS_DESTRUCTOR) {
231 if (n->types & NOTIFY_EXTRA_ARG)
232 n->u.destroy2(from_tal_hdr(ctx),
235 n->u.destroy(from_tal_hdr(ctx));
237 n->u.notifyfn(from_tal_hdr(ctx), type,
243 static void *allocate(size_t size)
245 void *ret = allocfn(size);
247 call_error("allocation failed");
249 update_bounds(ret, size);
253 static struct prop_hdr **find_property_ptr(const struct tal_hdr *t,
258 for (p = (struct prop_hdr **)&t->prop; *p; p = &(*p)->next) {
259 if (is_literal(*p)) {
264 if ((*p)->type == type)
270 static void *find_property(const struct tal_hdr *parent, enum prop_type type)
272 struct prop_hdr **p = find_property_ptr(parent, type);
279 static void init_property(struct prop_hdr *hdr,
280 struct tal_hdr *parent,
284 hdr->next = parent->prop;
288 static struct notifier *add_notifier_property(struct tal_hdr *t,
289 enum tal_notify_type types,
291 enum tal_notify_type,
295 struct notifier *prop;
297 if (types & NOTIFY_EXTRA_ARG)
298 prop = allocate(sizeof(struct notifier_extra_arg));
300 prop = allocate(sizeof(struct notifier));
303 init_property(&prop->hdr, t, NOTIFIER);
305 prop->u.notifyfn = fn;
306 if (types & NOTIFY_EXTRA_ARG)
307 EXTRA_ARG(prop) = extra_arg;
312 static enum tal_notify_type del_notifier_property(struct tal_hdr *t,
314 enum tal_notify_type,
316 bool match_extra_arg,
321 for (p = (struct prop_hdr **)&t->prop; *p; p = &(*p)->next) {
323 enum tal_notify_type types;
327 if ((*p)->type != NOTIFIER)
329 n = (struct notifier *)*p;
330 if (n->u.notifyfn != fn)
334 if ((types & NOTIFY_EXTRA_ARG)
336 && extra_arg != EXTRA_ARG(n))
341 return types & ~(NOTIFY_IS_DESTRUCTOR|NOTIFY_EXTRA_ARG);
346 static struct name *add_name_property(struct tal_hdr *t, const char *name)
350 prop = allocate(sizeof(*prop) + strlen(name) + 1);
352 init_property(&prop->hdr, t, NAME);
353 strcpy(prop->name, name);
358 static struct children *add_child_property(struct tal_hdr *parent,
359 struct tal_hdr *child UNNEEDED)
361 struct children *prop = allocate(sizeof(*prop));
363 init_property(&prop->hdr, parent, CHILDREN);
364 prop->parent = parent;
365 list_head_init(&prop->children);
370 static bool add_child(struct tal_hdr *parent, struct tal_hdr *child)
372 struct children *children = find_property(parent, CHILDREN);
375 children = add_child_property(parent, child);
379 list_add(&children->children, &child->list);
380 child->parent_child = children;
384 static void del_tree(struct tal_hdr *t, const tal_t *orig, int saved_errno)
386 struct prop_hdr **prop, *p, *next;
388 /* Already being destroyed? Don't loop. */
389 if (unlikely(get_destroying_bit(t->parent_child)))
392 set_destroying_bit(&t->parent_child);
394 /* Call free notifiers. */
395 notify(t, TAL_NOTIFY_FREE, (tal_t *)orig, saved_errno);
397 /* Now free children and groups. */
398 prop = find_property_ptr(t, CHILDREN);
401 struct children *c = (struct children *)*prop;
403 while ((i = list_top(&c->children, struct tal_hdr, list))) {
405 del_tree(i, orig, saved_errno);
409 /* Finally free our properties. */
410 for (p = t->prop; p && !is_literal(p); p = next) {
412 /* LENGTH is appended, so don't free separately! */
413 if (p->type != LENGTH)
419 static size_t extra_for_length(size_t size)
422 const size_t align = ALIGNOF(struct length);
424 /* Round up size, and add tailer. */
425 extra = ((size + align-1) & ~(align-1)) - size;
426 extra += sizeof(struct length);
430 void *tal_alloc_(const tal_t *ctx, size_t size,
431 bool clear, bool add_length, const char *label)
433 size_t req_size = size;
434 struct tal_hdr *child, *parent = debug_tal(to_tal_hdr_or_null(ctx));
436 #ifdef CCAN_TAL_DEBUG
437 /* Always record length if debugging. */
441 size += extra_for_length(size);
443 child = allocate(sizeof(struct tal_hdr) + size);
447 memset(from_tal_hdr(child), 0, req_size);
448 child->prop = (void *)label;
451 struct length *lprop;
452 lprop = (struct length *)((char *)(child+1) + size) - 1;
453 init_property(&lprop->hdr, child, LENGTH);
454 lprop->len = req_size;
456 if (!add_child(parent, child)) {
462 notify(parent, TAL_NOTIFY_ADD_CHILD, from_tal_hdr(child), 0);
463 return from_tal_hdr(debug_tal(child));
466 static bool adjust_size(size_t *size, size_t count)
468 const size_t extra = sizeof(struct tal_hdr) + sizeof(struct length)*2;
470 /* Multiplication wrap */
471 if (count && unlikely(*size * count / *size != count))
476 /* Make sure we don't wrap adding header/tailer. */
477 if (*size + extra < extra)
481 call_error("allocation size overflow");
485 void *tal_alloc_arr_(const tal_t *ctx, size_t size, size_t count, bool clear,
486 bool add_length, const char *label)
488 if (!adjust_size(&size, count))
491 return tal_alloc_(ctx, size, clear, add_length, label);
494 void *tal_free(const tal_t *ctx)
498 int saved_errno = errno;
499 t = debug_tal(to_tal_hdr(ctx));
501 notify(ignore_destroying_bit(t->parent_child)->parent,
502 TAL_NOTIFY_DEL_CHILD, ctx, saved_errno);
504 del_tree(t, ctx, saved_errno);
510 void *tal_steal_(const tal_t *new_parent, const tal_t *ctx)
513 struct tal_hdr *newpar, *t, *old_parent;
515 newpar = debug_tal(to_tal_hdr_or_null(new_parent));
516 t = debug_tal(to_tal_hdr(ctx));
518 /* Unlink it from old parent. */
520 old_parent = ignore_destroying_bit(t->parent_child)->parent;
522 if (unlikely(!add_child(newpar, t))) {
523 /* We can always add to old parent, becuase it has a
524 * children property already. */
525 if (!add_child(old_parent, t))
531 notify(t, TAL_NOTIFY_STEAL, new_parent, 0);
536 bool tal_add_destructor_(const tal_t *ctx, void (*destroy)(void *me))
538 tal_t *t = debug_tal(to_tal_hdr(ctx));
539 return add_notifier_property(t, TAL_NOTIFY_FREE|NOTIFY_IS_DESTRUCTOR,
540 (void *)destroy, NULL);
543 bool tal_add_destructor2_(const tal_t *ctx, void (*destroy)(void *me, void *arg),
546 tal_t *t = debug_tal(to_tal_hdr(ctx));
547 return add_notifier_property(t, TAL_NOTIFY_FREE|NOTIFY_IS_DESTRUCTOR
549 (void *)destroy, arg);
552 /* We could support notifiers with an extra arg, but we didn't add to API */
553 bool tal_add_notifier_(const tal_t *ctx, enum tal_notify_type types,
554 void (*callback)(tal_t *, enum tal_notify_type, void *))
556 tal_t *t = debug_tal(to_tal_hdr(ctx));
560 assert((types & ~(TAL_NOTIFY_FREE | TAL_NOTIFY_STEAL | TAL_NOTIFY_MOVE
561 | TAL_NOTIFY_RESIZE | TAL_NOTIFY_RENAME
562 | TAL_NOTIFY_ADD_CHILD | TAL_NOTIFY_DEL_CHILD
563 | TAL_NOTIFY_ADD_NOTIFIER
564 | TAL_NOTIFY_DEL_NOTIFIER)) == 0);
566 /* Don't call notifier about itself: set types after! */
567 n = add_notifier_property(t, 0, callback, NULL);
572 notify(t, TAL_NOTIFY_ADD_NOTIFIER, callback, 0);
575 if (types != TAL_NOTIFY_FREE)
580 bool tal_del_notifier_(const tal_t *ctx,
581 void (*callback)(tal_t *, enum tal_notify_type, void *),
582 bool match_extra_arg, void *extra_arg)
584 struct tal_hdr *t = debug_tal(to_tal_hdr(ctx));
585 enum tal_notify_type types;
587 types = del_notifier_property(t, callback, match_extra_arg, extra_arg);
589 notify(t, TAL_NOTIFY_DEL_NOTIFIER, callback, 0);
590 if (types != TAL_NOTIFY_FREE)
597 bool tal_del_destructor_(const tal_t *ctx, void (*destroy)(void *me))
599 return tal_del_notifier_(ctx, (void *)destroy, false, NULL);
602 bool tal_del_destructor2_(const tal_t *ctx, void (*destroy)(void *me, void *arg),
605 return tal_del_notifier_(ctx, (void *)destroy, true, arg);
608 bool tal_set_name_(tal_t *ctx, const char *name, bool literal)
610 struct tal_hdr *t = debug_tal(to_tal_hdr(ctx));
611 struct prop_hdr **prop = find_property_ptr(t, NAME);
613 /* Get rid of any old name */
615 struct name *name = (struct name *)*prop;
616 if (is_literal(&name->hdr))
619 *prop = name->hdr.next;
624 if (literal && name[0]) {
627 /* Append literal. */
628 for (p = &t->prop; *p && !is_literal(*p); p = &(*p)->next);
629 *p = (struct prop_hdr *)name;
630 } else if (!add_name_property(t, name))
635 notify(t, TAL_NOTIFY_RENAME, name, 0);
639 const char *tal_name(const tal_t *t)
643 n = find_property(debug_tal(to_tal_hdr(t)), NAME);
647 if (is_literal(&n->hdr))
648 return (const char *)n;
652 size_t tal_len(const tal_t *ptr)
659 l = find_property(debug_tal(to_tal_hdr(ptr)), LENGTH);
665 /* Start one past first child: make stopping natural in circ. list. */
666 static struct tal_hdr *first_child(struct tal_hdr *parent)
668 struct children *child;
670 child = find_property(parent, CHILDREN);
674 return list_top(&child->children, struct tal_hdr, list);
677 tal_t *tal_first(const tal_t *root)
679 struct tal_hdr *c, *t = debug_tal(to_tal_hdr_or_null(root));
684 return from_tal_hdr(c);
687 tal_t *tal_next(const tal_t *prev)
689 struct tal_hdr *next, *prevhdr = debug_tal(to_tal_hdr(prev));
690 struct list_head *head;
692 head = &ignore_destroying_bit(prevhdr->parent_child)->children;
693 next = list_next(head, prevhdr, list);
696 return from_tal_hdr(next);
699 tal_t *tal_parent(const tal_t *ctx)
706 t = debug_tal(to_tal_hdr(ctx));
707 if (ignore_destroying_bit(t->parent_child)->parent == &null_parent.hdr)
709 return from_tal_hdr(ignore_destroying_bit(t->parent_child)->parent);
712 bool tal_resize_(tal_t **ctxp, size_t size, size_t count, bool clear)
714 struct tal_hdr *old_t, *t;
715 struct children *child;
716 struct prop_hdr **lenp;
720 old_t = debug_tal(to_tal_hdr(*ctxp));
722 if (!adjust_size(&size, count))
725 lenp = find_property_ptr(old_t, LENGTH);
727 /* Copy here, in case we're shrinking! */
728 len = *(struct length *)*lenp;
729 extra = extra_for_length(size);
730 } else /* If we don't have an old length, we can't clear! */
733 t = resizefn(old_t, sizeof(struct tal_hdr) + size + extra);
735 call_error("Reallocation failure");
739 /* Copy length to end. */
741 struct length *new_len;
743 /* Clear between old end and new end. */
744 if (clear && size > len.len) {
745 char *old_end = (char *)(t + 1) + len.len;
746 memset(old_end, 0, size - len.len);
749 new_len = (struct length *)((char *)(t + 1) + size
750 + extra - sizeof(len));
754 /* Be careful replacing next ptr; could be old hdr. */
755 if (lenp == &old_t->prop)
756 t->prop = &new_len->hdr;
758 *lenp = &new_len->hdr;
761 update_bounds(t, sizeof(struct tal_hdr) + size + extra);
763 /* If it didn't move, we're done! */
765 /* Fix up linked list pointers. */
766 t->list.next->prev = t->list.prev->next = &t->list;
768 /* Fix up child property's parent pointer. */
769 child = find_property(t, CHILDREN);
771 assert(child->parent == old_t);
774 *ctxp = from_tal_hdr(debug_tal(t));
776 notify(t, TAL_NOTIFY_MOVE, from_tal_hdr(old_t), 0);
779 notify(t, TAL_NOTIFY_RESIZE, (void *)size, 0);
784 bool tal_expand_(tal_t **ctxp, const void *src, size_t size, size_t count)
790 l = find_property(debug_tal(to_tal_hdr(*ctxp)), LENGTH);
793 /* Check for additive overflow */
794 if (old_len + count * size < old_len) {
795 call_error("dup size overflow");
799 /* Don't point src inside thing we're expanding! */
801 || (char *)src >= (char *)(*ctxp) + old_len);
803 if (!tal_resize_(ctxp, size, old_len/size + count, false))
806 memcpy((char *)*ctxp + old_len, src, count * size);
815 void *tal_dup_(const tal_t *ctx, const void *p, size_t size,
816 size_t n, size_t extra, bool add_length,
820 size_t nbytes = size;
822 if (!adjust_size(&nbytes, n)) {
828 /* Beware addition overflow! */
830 call_error("dup size overflow");
839 if (unlikely(!tal_resize_((void **)&p, size, n + extra, false)))
841 if (unlikely(!tal_steal(ctx, p)))
846 ret = tal_alloc_arr_(ctx, size, n + extra, false, add_length, label);
848 memcpy(ret, p, nbytes);
852 void tal_set_backend(void *(*alloc_fn)(size_t size),
853 void *(*resize_fn)(void *, size_t size),
854 void (*free_fn)(void *),
855 void (*error_fn)(const char *msg))
860 resizefn = resize_fn;
867 #ifdef CCAN_TAL_DEBUG
868 static void dump_node(unsigned int indent, const struct tal_hdr *t)
871 const struct prop_hdr *p;
873 for (i = 0; i < indent; i++)
876 for (p = t->prop; p; p = p->next) {
882 printf(" \"%s\"", (const char *)p);
887 c = (struct children *)p;
888 printf(" CHILDREN(%p):parent=%p,children={%p,%p}\n",
890 c->children.n.prev, c->children.n.next);
893 n = (struct name *)p;
894 printf(" NAME(%p):%s", p, n->name);
897 no = (struct notifier *)p;
898 printf(" NOTIFIER(%p):fn=%p", p, no->u.notifyfn);
901 l = (struct length *)p;
902 printf(" LENGTH(%p):len=%zu", p, l->len);
905 printf(" **UNKNOWN(%p):%i**", p, p->type);
911 static void tal_dump_(unsigned int level, const struct tal_hdr *t)
913 struct children *children;
917 children = find_property(t, CHILDREN);
921 list_for_each(&children->children, i, list)
922 tal_dump_(level + 1, i);
928 tal_dump_(0, &null_parent.hdr);
930 #endif /* CCAN_TAL_DEBUG */
933 static bool check_err(struct tal_hdr *t, const char *errorstr,
937 /* Try not to malloc: it may be corrupted. */
938 char msg[strlen(errorstr) + 20 + strlen(errmsg) + 1];
939 sprintf(msg, "%s:%p %s", errorstr, from_tal_hdr(t), errmsg);
945 static bool check_node(struct children *parent_child,
946 struct tal_hdr *t, const char *errorstr)
949 struct name *name = NULL;
950 struct children *children = NULL;
951 struct length *length = NULL;
954 return check_err(t, errorstr, "invalid pointer");
956 if (ignore_destroying_bit(t->parent_child) != parent_child)
957 return check_err(t, errorstr, "incorrect parent");
959 for (p = t->prop; p; p = p->next) {
962 return check_err(t, errorstr,
963 "has extra literal");
967 return check_err(t, errorstr,
968 "has bad property pointer");
973 return check_err(t, errorstr,
974 "has two child nodes");
975 children = (struct children *)p;
979 return check_err(t, errorstr,
981 length = (struct length *)p;
987 return check_err(t, errorstr,
989 name = (struct name *)p;
992 return check_err(t, errorstr, "has unknown property");
998 if (!list_check(&children->children, errorstr))
1000 list_for_each(&children->children, i, list) {
1001 if (!check_node(children, i, errorstr))
1008 bool tal_check(const tal_t *ctx, const char *errorstr)
1010 struct tal_hdr *t = to_tal_hdr_or_null(ctx);
1012 return check_node(ignore_destroying_bit(t->parent_child), t, errorstr);
1015 bool tal_check(const tal_t *ctx, const char *errorstr)