]> git.ozlabs.org Git - ccan/blobdiff - ccan/tal/tal.c
tal: make tal_len/tal_count(NULL) return 0.
[ccan] / ccan / tal / tal.c
index 5c0aec07990dcbafc44b5e7bf075ac8c68ba5641..555dd1333d8f7be28ae837b4a4f0d1cba5686d07 100644 (file)
@@ -3,6 +3,7 @@
 #include <ccan/compiler/compiler.h>
 #include <ccan/list/list.h>
 #include <ccan/take/take.h>
+#include <ccan/alignof/alignof.h>
 #include <assert.h>
 #include <stdio.h>
 #include <stddef.h>
@@ -13,6 +14,7 @@
 //#define TAL_DEBUG 1
 
 #define NOTIFY_IS_DESTRUCTOR 512
+#define NOTIFY_EXTRA_ARG 1024
 
 /* 32-bit type field, first byte 0 in either endianness. */
 enum prop_type {
@@ -46,7 +48,7 @@ struct name {
 
 struct length {
        struct prop_hdr hdr; /* LENGTH */
-       size_t count;
+       size_t len;
 };
 
 struct notifier {
@@ -55,9 +57,18 @@ struct notifier {
        union {
                void (*notifyfn)(tal_t *, enum tal_notify_type, void *);
                void (*destroy)(tal_t *); /* If NOTIFY_IS_DESTRUCTOR set */
+               void (*destroy2)(tal_t *, void *); /* If NOTIFY_EXTRA_ARG */
        } u;
 };
 
+/* Extra arg */
+struct notifier_extra_arg {
+       struct notifier n;
+       void *arg;
+};
+
+#define EXTRA_ARG(n) (((struct notifier_extra_arg *)(n))->arg)
+
 static struct {
        struct tal_hdr hdr;
        struct children c;
@@ -75,7 +86,6 @@ static void *(*allocfn)(size_t size) = malloc;
 static void *(*resizefn)(void *, size_t size) = realloc;
 static void (*freefn)(void *) = free;
 static void (*errorfn)(const char *msg) = (void *)abort;
-static bool initialized = false;
 /* Count on non-destrutor notifiers; often stays zero. */
 static size_t notifiers = 0;
 
@@ -100,23 +110,19 @@ static struct children *ignore_destroying_bit(struct children *parent_child)
 }
 
 /* This means valgrind can see leaks. */
-static void tal_cleanup(void)
+void tal_cleanup(void)
 {
        struct tal_hdr *i;
 
-       while ((i = list_top(&null_parent.c.children, struct tal_hdr, list)))
+       while ((i = list_top(&null_parent.c.children, struct tal_hdr, list))) {
                list_del(&i->list);
+               memset(i, 0, sizeof(*i));
+       }
 
        /* Cleanup any taken pointers. */
        take_cleanup();
 }
 
-/* For allocation failures inside ccan/take */
-static void take_alloc_failed(const void *p)
-{
-       tal_free(p);
-}
-
 /* We carefully start all real properties with a zero byte. */
 static bool is_literal(const struct prop_hdr *prop)
 {
@@ -207,7 +213,8 @@ static struct tal_hdr *debug_tal(struct tal_hdr *tal)
 #endif
 
 static void notify(const struct tal_hdr *ctx,
-                  enum tal_notify_type type, const void *info)
+                  enum tal_notify_type type, const void *info,
+                  int saved_errno)
 {
         const struct prop_hdr *p;
 
@@ -220,9 +227,14 @@ static void notify(const struct tal_hdr *ctx,
                        continue;
                n = (struct notifier *)p;
                if (n->types & type) {
-                       if (n->types & NOTIFY_IS_DESTRUCTOR)
-                               n->u.destroy(from_tal_hdr(ctx));
-                       else
+                       errno = saved_errno;
+                       if (n->types & NOTIFY_IS_DESTRUCTOR) {
+                               if (n->types & NOTIFY_EXTRA_ARG)
+                                       n->u.destroy2(from_tal_hdr(ctx),
+                                                     EXTRA_ARG(n));
+                               else
+                                       n->u.destroy(from_tal_hdr(ctx));
+                       } else
                                n->u.notifyfn(from_tal_hdr(ctx), type,
                                              (void *)info);
                }
@@ -278,13 +290,22 @@ static struct notifier *add_notifier_property(struct tal_hdr *t,
                                              enum tal_notify_type types,
                                              void (*fn)(void *,
                                                         enum tal_notify_type,
-                                                        void *))
+                                                        void *),
+                                             void *extra_arg)
 {
-       struct notifier *prop = allocate(sizeof(*prop));
+       struct notifier *prop;
+
+       if (types & NOTIFY_EXTRA_ARG)
+               prop = allocate(sizeof(struct notifier_extra_arg));
+       else
+               prop = allocate(sizeof(struct notifier));
+
        if (prop) {
                init_property(&prop->hdr, t, NOTIFIER);
                prop->types = types;
                prop->u.notifyfn = fn;
+               if (types & NOTIFY_EXTRA_ARG)
+                       EXTRA_ARG(prop) = extra_arg;
        }
        return prop;
 }
@@ -292,24 +313,33 @@ static struct notifier *add_notifier_property(struct tal_hdr *t,
 static enum tal_notify_type del_notifier_property(struct tal_hdr *t,
                                                  void (*fn)(tal_t *,
                                                             enum tal_notify_type,
-                                                            void *))
+                                                            void *),
+                                                 bool match_extra_arg,
+                                                 void *extra_arg)
 {
         struct prop_hdr **p;
 
         for (p = (struct prop_hdr **)&t->prop; *p; p = &(*p)->next) {
                struct notifier *n;
+               enum tal_notify_type types;
 
                 if (is_literal(*p))
                        break;
                 if ((*p)->type != NOTIFIER)
                        continue;
                n = (struct notifier *)*p;
-               if (n->u.notifyfn == fn) {
-                       enum tal_notify_type types = n->types;
-                       *p = (*p)->next;
-                       freefn(n);
-                       return types & ~NOTIFY_IS_DESTRUCTOR;
-               }
+               if (n->u.notifyfn != fn)
+                       continue;
+
+               types = n->types;
+               if ((types & NOTIFY_EXTRA_ARG)
+                   && match_extra_arg
+                   && extra_arg != EXTRA_ARG(n))
+                       continue;
+
+               *p = (*p)->next;
+               freefn(n);
+               return types & ~(NOTIFY_IS_DESTRUCTOR|NOTIFY_EXTRA_ARG);
         }
         return 0;
 }
@@ -326,20 +356,8 @@ static struct name *add_name_property(struct tal_hdr *t, const char *name)
        return prop;
 }
 
-static struct length *add_length_property(struct tal_hdr *t, size_t count)
-{
-       struct length *prop;
-
-       prop = allocate(sizeof(*prop));
-       if (prop) {
-               init_property(&prop->hdr, t, LENGTH);
-               prop->count = count;
-       }
-       return prop;
-}
-
 static struct children *add_child_property(struct tal_hdr *parent,
-                                          struct tal_hdr *child)
+                                          struct tal_hdr *child UNNEEDED)
 {
        struct children *prop = allocate(sizeof(*prop));
        if (prop) {
@@ -355,11 +373,6 @@ static bool add_child(struct tal_hdr *parent, struct tal_hdr *child)
        struct children *children = find_property(parent, CHILDREN);
 
         if (!children) {
-               if (unlikely(!initialized)) {
-                       atexit(tal_cleanup);
-                       take_allocfail(take_alloc_failed);
-                       initialized = true;
-               }
                children = add_child_property(parent, child);
                if (!children)
                        return false;
@@ -369,7 +382,7 @@ static bool add_child(struct tal_hdr *parent, struct tal_hdr *child)
        return true;
 }
 
-static void del_tree(struct tal_hdr *t, const tal_t *orig)
+static void del_tree(struct tal_hdr *t, const tal_t *orig, int saved_errno)
 {
        struct prop_hdr **prop, *p, *next;
 
@@ -380,7 +393,7 @@ static void del_tree(struct tal_hdr *t, const tal_t *orig)
         set_destroying_bit(&t->parent_child);
 
        /* Call free notifiers. */
-       notify(t, TAL_NOTIFY_FREE, (tal_t *)orig);
+       notify(t, TAL_NOTIFY_FREE, (tal_t *)orig, saved_errno);
 
        /* Now free children and groups. */
        prop = find_property_ptr(t, CHILDREN);
@@ -390,48 +403,79 @@ static void del_tree(struct tal_hdr *t, const tal_t *orig)
 
                while ((i = list_top(&c->children, struct tal_hdr, list))) {
                        list_del(&i->list);
-                       del_tree(i, orig);
+                       del_tree(i, orig, saved_errno);
                }
        }
 
         /* Finally free our properties. */
         for (p = t->prop; p && !is_literal(p); p = next) {
                 next = p->next;
-               freefn(p);
+               /* LENGTH is appended, so don't free separately! */
+               if (p->type != LENGTH)
+                       freefn(p);
         }
         freefn(t);
 }
 
-void *tal_alloc_(const tal_t *ctx, size_t size, bool clear, const char *label)
+static size_t extra_for_length(size_t size)
+{
+       size_t extra;
+       const size_t align = ALIGNOF(struct length);
+
+       /* Round up size, and add tailer. */
+       extra = ((size + align-1) & ~(align-1)) - size;
+       extra += sizeof(struct length);
+       return extra;
+}
+
+void *tal_alloc_(const tal_t *ctx, size_t size,
+                bool clear, bool add_length, const char *label)
 {
+       size_t req_size = size;
         struct tal_hdr *child, *parent = debug_tal(to_tal_hdr_or_null(ctx));
 
+#ifdef CCAN_TAL_DEBUG
+       /* Always record length if debugging. */
+       add_length = true;
+#endif
+       if (add_length)
+               size += extra_for_length(size);
+
         child = allocate(sizeof(struct tal_hdr) + size);
        if (!child)
                return NULL;
        if (clear)
-               memset(from_tal_hdr(child), 0, size);
+               memset(from_tal_hdr(child), 0, req_size);
         child->prop = (void *)label;
+
+       if (add_length) {
+               struct length *lprop;
+               lprop = (struct length *)((char *)(child+1) + size) - 1;
+               init_property(&lprop->hdr, child, LENGTH);
+               lprop->len = req_size;
+       }
         if (!add_child(parent, child)) {
                freefn(child);
                return NULL;
        }
        debug_tal(parent);
        if (notifiers)
-               notify(parent, TAL_NOTIFY_ADD_CHILD, from_tal_hdr(child));
+               notify(parent, TAL_NOTIFY_ADD_CHILD, from_tal_hdr(child), 0);
        return from_tal_hdr(debug_tal(child));
 }
 
 static bool adjust_size(size_t *size, size_t count)
 {
+       const size_t extra = sizeof(struct tal_hdr) + sizeof(struct length)*2;
+
        /* Multiplication wrap */
         if (count && unlikely(*size * count / *size != count))
                goto overflow;
 
         *size *= count;
 
-        /* Make sure we don't wrap adding header. */
-        if (*size + sizeof(struct tal_hdr) < sizeof(struct tal_hdr))
+        /* Make sure we don't wrap adding header/tailer. */
+        if (*size + extra < extra)
                goto overflow;
        return true;
 overflow:
@@ -440,19 +484,12 @@ overflow:
 }
 
 void *tal_alloc_arr_(const tal_t *ctx, size_t size, size_t count, bool clear,
-                    bool add_count, const char *label)
+                    bool add_length, const char *label)
 {
-       void *ret;
-
        if (!adjust_size(&size, count))
                return NULL;
 
-       ret = tal_alloc_(ctx, size, clear, label);
-       if (likely(ret) && add_count) {
-               if (unlikely(!add_length_property(to_tal_hdr(ret), count)))
-                       ret = tal_free(ret);
-       }
-       return ret;
+       return tal_alloc_(ctx, size, clear, add_length, label);
 }
 
 void *tal_free(const tal_t *ctx)
@@ -463,9 +500,9 @@ void *tal_free(const tal_t *ctx)
                t = debug_tal(to_tal_hdr(ctx));
                if (notifiers)
                        notify(ignore_destroying_bit(t->parent_child)->parent,
-                              TAL_NOTIFY_DEL_CHILD, ctx);
+                              TAL_NOTIFY_DEL_CHILD, ctx, saved_errno);
                list_del(&t->list);
-               del_tree(t, ctx);
+               del_tree(t, ctx, saved_errno);
                errno = saved_errno;
        }
        return NULL;
@@ -492,7 +529,7 @@ void *tal_steal_(const tal_t *new_parent, const tal_t *ctx)
                }
                debug_tal(newpar);
                if (notifiers)
-                       notify(t, TAL_NOTIFY_STEAL, new_parent);
+                       notify(t, TAL_NOTIFY_STEAL, new_parent, 0);
         }
         return (void *)ctx;
 }
@@ -501,9 +538,19 @@ bool tal_add_destructor_(const tal_t *ctx, void (*destroy)(void *me))
 {
        tal_t *t = debug_tal(to_tal_hdr(ctx));
        return add_notifier_property(t, TAL_NOTIFY_FREE|NOTIFY_IS_DESTRUCTOR,
-                                    (void *)destroy);
+                                    (void *)destroy, NULL);
+}
+
+bool tal_add_destructor2_(const tal_t *ctx, void (*destroy)(void *me, void *arg),
+                         void *arg)
+{
+       tal_t *t = debug_tal(to_tal_hdr(ctx));
+       return add_notifier_property(t, TAL_NOTIFY_FREE|NOTIFY_IS_DESTRUCTOR
+                                    |NOTIFY_EXTRA_ARG,
+                                    (void *)destroy, arg);
 }
 
+/* We could support notifiers with an extra arg, but we didn't add to API */
 bool tal_add_notifier_(const tal_t *ctx, enum tal_notify_type types,
                       void (*callback)(tal_t *, enum tal_notify_type, void *))
 {
@@ -518,12 +565,12 @@ bool tal_add_notifier_(const tal_t *ctx, enum tal_notify_type types,
                          | TAL_NOTIFY_DEL_NOTIFIER)) == 0);
 
        /* Don't call notifier about itself: set types after! */
-        n = add_notifier_property(t, 0, callback);
+        n = add_notifier_property(t, 0, callback, NULL);
        if (unlikely(!n))
                return false;
 
        if (notifiers)
-               notify(t, TAL_NOTIFY_ADD_NOTIFIER, callback);
+               notify(t, TAL_NOTIFY_ADD_NOTIFIER, callback, 0);
 
        n->types = types;
        if (types != TAL_NOTIFY_FREE)
@@ -532,14 +579,15 @@ bool tal_add_notifier_(const tal_t *ctx, enum tal_notify_type types,
 }
 
 bool tal_del_notifier_(const tal_t *ctx,
-                      void (*callback)(tal_t *, enum tal_notify_type, void *))
+                      void (*callback)(tal_t *, enum tal_notify_type, void *),
+                      bool match_extra_arg, void *extra_arg)
 {
        struct tal_hdr *t = debug_tal(to_tal_hdr(ctx));
        enum tal_notify_type types;
 
-        types = del_notifier_property(t, callback);
+        types = del_notifier_property(t, callback, match_extra_arg, extra_arg);
        if (types) {
-               notify(t, TAL_NOTIFY_DEL_NOTIFIER, callback);
+               notify(t, TAL_NOTIFY_DEL_NOTIFIER, callback, 0);
                if (types != TAL_NOTIFY_FREE)
                        notifiers--;
                return true;
@@ -549,7 +597,13 @@ bool tal_del_notifier_(const tal_t *ctx,
 
 bool tal_del_destructor_(const tal_t *ctx, void (*destroy)(void *me))
 {
-       return tal_del_notifier_(ctx, (void *)destroy);
+       return tal_del_notifier_(ctx, (void *)destroy, false, NULL);
+}
+
+bool tal_del_destructor2_(const tal_t *ctx, void (*destroy)(void *me, void *arg),
+                         void *arg)
+{
+       return tal_del_notifier_(ctx, (void *)destroy, true, arg);
 }
 
 bool tal_set_name_(tal_t *ctx, const char *name, bool literal)
@@ -579,7 +633,7 @@ bool tal_set_name_(tal_t *ctx, const char *name, bool literal)
 
        debug_tal(t);
        if (notifiers)
-               notify(t, TAL_NOTIFY_RENAME, name);
+               notify(t, TAL_NOTIFY_RENAME, name, 0);
        return true;
 }
 
@@ -596,14 +650,17 @@ const char *tal_name(const tal_t *t)
        return n->name;
 }
 
-size_t tal_count(const tal_t *ptr)
+size_t tal_len(const tal_t *ptr)
 {
        struct length *l;
 
+       if (!ptr)
+               return 0;
+
        l = find_property(debug_tal(to_tal_hdr(ptr)), LENGTH);
        if (!l)
                return 0;
-       return l->count;
+       return l->len;
 }
 
 /* Start one past first child: make stopping natural in circ. list. */
@@ -628,31 +685,16 @@ tal_t *tal_first(const tal_t *root)
        return from_tal_hdr(c);
 }
 
-tal_t *tal_next(const tal_t *root, const tal_t *prev)
+tal_t *tal_next(const tal_t *prev)
 {
-        struct tal_hdr *c, *t = debug_tal(to_tal_hdr(prev)), *top;
-
-        /* Children? */
-       c = first_child(t);
-       if (c)
-               return from_tal_hdr(c);
+        struct tal_hdr *next, *prevhdr = debug_tal(to_tal_hdr(prev));
+       struct list_head *head;
 
-        top = to_tal_hdr_or_null(root);
-        do {
-               struct tal_hdr *next;
-               struct list_node *end;
-
-               end = &ignore_destroying_bit(t->parent_child)->children.n;
-
-               next = list_entry(t->list.next, struct tal_hdr, list);
-               if (&next->list != end)
-                       return from_tal_hdr(next);
-
-                /* OK, go back to parent. */
-                t = ignore_destroying_bit(t->parent_child)->parent;
-        } while (t != top);
-
-        return NULL;
+       head = &ignore_destroying_bit(prevhdr->parent_child)->children;
+       next = list_next(head, prevhdr, list);
+       if (!next)
+               return NULL;
+       return from_tal_hdr(next);
 }
 
 tal_t *tal_parent(const tal_t *ctx)
@@ -668,30 +710,61 @@ tal_t *tal_parent(const tal_t *ctx)
         return from_tal_hdr(ignore_destroying_bit(t->parent_child)->parent);
 }
 
-bool tal_resize_(tal_t **ctxp, size_t size, size_t count)
+bool tal_resize_(tal_t **ctxp, size_t size, size_t count, bool clear)
 {
         struct tal_hdr *old_t, *t;
         struct children *child;
-       struct length *len;
+       struct prop_hdr **lenp;
+       struct length len;
+       size_t extra = 0;
 
         old_t = debug_tal(to_tal_hdr(*ctxp));
 
        if (!adjust_size(&size, count))
                return false;
 
-        t = resizefn(old_t, size + sizeof(struct tal_hdr));
+       lenp = find_property_ptr(old_t, LENGTH);
+       if (lenp) {
+               /* Copy here, in case we're shrinking! */
+               len = *(struct length *)*lenp;
+               extra = extra_for_length(size);
+       } else /* If we don't have an old length, we can't clear! */
+               assert(!clear);
+
+        t = resizefn(old_t, sizeof(struct tal_hdr) + size + extra);
        if (!t) {
                call_error("Reallocation failure");
                return false;
        }
 
+       /* Copy length to end. */
+       if (lenp) {
+               struct length *new_len;
+
+               /* Clear between old end and new end. */
+               if (clear && size > len.len) {
+                       char *old_end = (char *)(t + 1) + len.len;
+                       memset(old_end, 0, size - len.len);
+               }
+
+               new_len = (struct length *)((char *)(t + 1) + size
+                                           + extra - sizeof(len));
+               len.len = size;
+               *new_len = len;
+
+               /* Be careful replacing next ptr; could be old hdr. */
+               if (lenp == &old_t->prop)
+                       t->prop = &new_len->hdr;
+               else
+                       *lenp = &new_len->hdr;
+       }
+
+       update_bounds(t, sizeof(struct tal_hdr) + size + extra);
+
        /* If it didn't move, we're done! */
         if (t != old_t) {
-               update_bounds(t, size + sizeof(struct tal_hdr));
-
                /* Fix up linked list pointers. */
-               if (list_entry(t->list.next, struct tal_hdr, list) != old_t)
-                       t->list.next->prev = t->list.prev->next = &t->list;
+               t->list.next->prev = t->list.prev->next = &t->list;
 
                /* Fix up child property's parent pointer. */
                child = find_property(t, CHILDREN);
@@ -701,13 +774,10 @@ bool tal_resize_(tal_t **ctxp, size_t size, size_t count)
                }
                *ctxp = from_tal_hdr(debug_tal(t));
                if (notifiers)
-                       notify(t, TAL_NOTIFY_MOVE, from_tal_hdr(old_t));
+                       notify(t, TAL_NOTIFY_MOVE, from_tal_hdr(old_t), 0);
        }
-       len = find_property(t, LENGTH);
-       if (len)
-               len->count = count;
        if (notifiers)
-               notify(t, TAL_NOTIFY_RESIZE, (void *)size);
+               notify(t, TAL_NOTIFY_RESIZE, (void *)size, 0);
 
        return true;
 }
@@ -715,26 +785,26 @@ bool tal_resize_(tal_t **ctxp, size_t size, size_t count)
 bool tal_expand_(tal_t **ctxp, const void *src, size_t size, size_t count)
 {
        struct length *l;
+       size_t old_len;
        bool ret = false;
 
        l = find_property(debug_tal(to_tal_hdr(*ctxp)), LENGTH);
+       old_len = l->len;
 
        /* Check for additive overflow */
-       if (l->count + count < count) {
+       if (old_len + count * size < old_len) {
                call_error("dup size overflow");
                goto out;
        }
 
        /* Don't point src inside thing we're expanding! */
        assert(src < *ctxp
-              || (char *)src >= (char *)(*ctxp) + (size * l->count));
+              || (char *)src >= (char *)(*ctxp) + old_len);
 
-       /* Note: updates l->count. */
-       if (!tal_resize_(ctxp, size, l->count + count))
+       if (!tal_resize_(ctxp, size, old_len/size + count, false))
                goto out;
 
-       memcpy((char *)*ctxp + size * (l->count - count),
-              src, count * size);
+       memcpy((char *)*ctxp + old_len, src, count * size);
        ret = true;
 
 out:
@@ -744,7 +814,7 @@ out:
 }
 
 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)
 {
        void *ret;
@@ -767,14 +837,14 @@ void *tal_dup_(const tal_t *ctx, const void *p, size_t size,
        if (taken(p)) {
                if (unlikely(!p))
                        return NULL;
-               if (unlikely(!tal_resize_((void **)&p, size, n + extra)))
+               if (unlikely(!tal_resize_((void **)&p, size, n + extra, false)))
                        return tal_free(p);
                if (unlikely(!tal_steal(ctx, p)))
                        return tal_free(p);
                return (void *)p;
        }
 
-       ret = tal_alloc_arr_(ctx, size, n + extra, false, add_count, label);
+       ret = tal_alloc_arr_(ctx, size, n + extra, false, add_length, label);
        if (ret)
                memcpy(ret, p, nbytes);
        return ret;
@@ -830,7 +900,7 @@ static void dump_node(unsigned int indent, const struct tal_hdr *t)
                        break;
                case LENGTH:
                        l = (struct length *)p;
-                       printf(" LENGTH(%p):count=%zu", p, l->count);
+                       printf(" LENGTH(%p):len=%zu", p, l->len);
                        break;
                default:
                        printf(" **UNKNOWN(%p):%i**", p, p->type);
@@ -892,7 +962,6 @@ static bool check_node(struct children *parent_child,
                        if (name)
                                return check_err(t, errorstr,
                                                 "has extra literal");
-                       name = (struct name *)p;
                        break;
                }
                if (!in_bounds(p))