[lvm-devel] master - [radix-tree] alternative radix-tree implementation.
Joe Thornber
thornber at sourceware.org
Tue Sep 11 12:27:17 UTC 2018
Gitweb: https://sourceware.org/git/?p=lvm2.git;a=commitdiff;h=4d964133e267b2b501a5dcd40c30cfdcfaa5903a
Commit: 4d964133e267b2b501a5dcd40c30cfdcfaa5903a
Parent: 22a13043683a5647e8cc4e3aead911e5269ffd2f
Author: Joe Thornber <ejt at redhat.com>
AuthorDate: Tue Sep 11 11:11:35 2018 +0100
Committer: Joe Thornber <ejt at redhat.com>
CommitterDate: Tue Sep 11 13:12:07 2018 +0100
[radix-tree] alternative radix-tree implementation.
Sacrifices performance for simplicity, meant only for verification of
the real adaptive implementation.
---
base/Makefile | 3 +
base/data-struct/radix-tree-adaptive.c | 1262 ++++++++++++++++++++++++++++++++
base/data-struct/radix-tree-simple.c | 256 +++++++
base/data-struct/radix-tree.c | 1251 +-------------------------------
4 files changed, 1526 insertions(+), 1246 deletions(-)
diff --git a/base/Makefile b/base/Makefile
index 02c4236..1823c9b 100644
--- a/base/Makefile
+++ b/base/Makefile
@@ -10,6 +10,9 @@
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+# Uncomment this to build the simple radix tree. You'll need to make clean too.
+# base/data-struct/radix-tree.o: CFLAGS += -DSIMPLE_RADIX_TREE
+
BASE_SOURCE=\
base/data-struct/radix-tree.c \
base/data-struct/hash.c \
diff --git a/base/data-struct/radix-tree-adaptive.c b/base/data-struct/radix-tree-adaptive.c
new file mode 100644
index 0000000..1eef1f8
--- /dev/null
+++ b/base/data-struct/radix-tree-adaptive.c
@@ -0,0 +1,1262 @@
+// Copyright (C) 2018 Red Hat, Inc. All rights reserved.
+//
+// This file is part of LVM2.
+//
+// This copyrighted material is made available to anyone wishing to use,
+// modify, copy, or redistribute it subject to the terms and conditions
+// of the GNU Lesser General Public License v.2.1.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program; if not, write to the Free Software Foundation,
+// Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+#include "radix-tree.h"
+
+#include "base/memory/container_of.h"
+#include "base/memory/zalloc.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+//----------------------------------------------------------------
+
+enum node_type {
+ UNSET = 0,
+ VALUE,
+ VALUE_CHAIN,
+ PREFIX_CHAIN,
+ NODE4,
+ NODE16,
+ NODE48,
+ NODE256
+};
+
+struct value {
+ enum node_type type;
+ union radix_value value;
+};
+
+// This is used for entries that have a key which is a prefix of another key.
+struct value_chain {
+ union radix_value value;
+ struct value child;
+};
+
+struct prefix_chain {
+ struct value child;
+ unsigned len;
+ uint8_t prefix[0];
+};
+
+struct node4 {
+ uint32_t nr_entries;
+ uint8_t keys[4];
+ struct value values[4];
+};
+
+struct node16 {
+ uint32_t nr_entries;
+ uint8_t keys[16];
+ struct value values[16];
+};
+
+struct node48 {
+ uint32_t nr_entries;
+ uint8_t keys[256];
+ struct value values[48];
+};
+
+struct node256 {
+ uint32_t nr_entries;
+ struct value values[256];
+};
+
+struct radix_tree {
+ unsigned nr_entries;
+ struct value root;
+ radix_value_dtr dtr;
+ void *dtr_context;
+};
+
+//----------------------------------------------------------------
+
+struct radix_tree *radix_tree_create(radix_value_dtr dtr, void *dtr_context)
+{
+ struct radix_tree *rt = malloc(sizeof(*rt));
+
+ if (rt) {
+ rt->nr_entries = 0;
+ rt->root.type = UNSET;
+ rt->dtr = dtr;
+ rt->dtr_context = dtr_context;
+ }
+
+ return rt;
+}
+
+static inline void _dtr(struct radix_tree *rt, union radix_value v)
+{
+ if (rt->dtr)
+ rt->dtr(rt->dtr_context, v);
+}
+
+// Returns the number of values removed
+static unsigned _free_node(struct radix_tree *rt, struct value v)
+{
+ unsigned i, nr = 0;
+ struct value_chain *vc;
+ struct prefix_chain *pc;
+ struct node4 *n4;
+ struct node16 *n16;
+ struct node48 *n48;
+ struct node256 *n256;
+
+ switch (v.type) {
+ case UNSET:
+ break;
+
+ case VALUE:
+ _dtr(rt, v.value);
+ nr = 1;
+ break;
+
+ case VALUE_CHAIN:
+ vc = v.value.ptr;
+ _dtr(rt, vc->value);
+ nr = 1 + _free_node(rt, vc->child);
+ free(vc);
+ break;
+
+ case PREFIX_CHAIN:
+ pc = v.value.ptr;
+ nr = _free_node(rt, pc->child);
+ free(pc);
+ break;
+
+ case NODE4:
+ n4 = (struct node4 *) v.value.ptr;
+ for (i = 0; i < n4->nr_entries; i++)
+ nr += _free_node(rt, n4->values[i]);
+ free(n4);
+ break;
+
+ case NODE16:
+ n16 = (struct node16 *) v.value.ptr;
+ for (i = 0; i < n16->nr_entries; i++)
+ nr += _free_node(rt, n16->values[i]);
+ free(n16);
+ break;
+
+ case NODE48:
+ n48 = (struct node48 *) v.value.ptr;
+ for (i = 0; i < n48->nr_entries; i++)
+ nr += _free_node(rt, n48->values[i]);
+ free(n48);
+ break;
+
+ case NODE256:
+ n256 = (struct node256 *) v.value.ptr;
+ for (i = 0; i < 256; i++)
+ nr += _free_node(rt, n256->values[i]);
+ free(n256);
+ break;
+ }
+
+ return nr;
+}
+
+void radix_tree_destroy(struct radix_tree *rt)
+{
+ _free_node(rt, rt->root);
+ free(rt);
+}
+
+unsigned radix_tree_size(struct radix_tree *rt)
+{
+ return rt->nr_entries;
+}
+
+static bool _insert(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv);
+
+static bool _insert_unset(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ unsigned len = ke - kb;
+
+ if (!len) {
+ // value
+ v->type = VALUE;
+ v->value = rv;
+ rt->nr_entries++;
+ } else {
+ // prefix -> value
+ struct prefix_chain *pc = zalloc(sizeof(*pc) + len);
+ if (!pc)
+ return false;
+
+ pc->child.type = VALUE;
+ pc->child.value = rv;
+ pc->len = len;
+ memcpy(pc->prefix, kb, len);
+ v->type = PREFIX_CHAIN;
+ v->value.ptr = pc;
+ rt->nr_entries++;
+ }
+
+ return true;
+}
+
+static bool _insert_value(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ unsigned len = ke - kb;
+
+ if (!len)
+ // overwrite
+ v->value = rv;
+
+ else {
+ // value_chain -> value
+ struct value_chain *vc = zalloc(sizeof(*vc));
+ if (!vc)
+ return false;
+
+ vc->value = v->value;
+ if (!_insert(rt, &vc->child, kb, ke, rv)) {
+ free(vc);
+ return false;
+ }
+
+ v->type = VALUE_CHAIN;
+ v->value.ptr = vc;
+ }
+
+ return true;
+}
+
+static bool _insert_value_chain(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ struct value_chain *vc = v->value.ptr;
+ return _insert(rt, &vc->child, kb, ke, rv);
+}
+
+static unsigned min(unsigned lhs, unsigned rhs)
+{
+ if (lhs <= rhs)
+ return lhs;
+ else
+ return rhs;
+}
+
+static bool _insert_prefix_chain(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ struct prefix_chain *pc = v->value.ptr;
+
+ if (!pc->len) {
+ v->type = VALUE;
+ v->value = rv;
+
+ } else if (*kb == pc->prefix[0]) {
+ // There's a common prefix let's split the chain into two and
+ // recurse.
+ struct prefix_chain *pc2;
+ unsigned i, len = min(pc->len, ke - kb);
+
+ for (i = 0; i < len; i++)
+ if (kb[i] != pc->prefix[i])
+ break;
+
+ pc2 = zalloc(sizeof(*pc2) + pc->len - i);
+ pc2->len = pc->len - i;
+ memmove(pc2->prefix, pc->prefix + i, pc2->len);
+ pc2->child = pc->child;
+
+ // FIXME: this trashes pc so we can't back out
+ pc->child.type = PREFIX_CHAIN;
+ pc->child.value.ptr = pc2;
+ pc->len = i;
+
+ if (!_insert(rt, &pc->child, kb + i, ke, rv)) {
+ free(pc2);
+ return false;
+ }
+
+ } else {
+ // Stick an n4 in front.
+ struct node4 *n4 = zalloc(sizeof(*n4));
+ if (!n4)
+ return false;
+
+ n4->keys[0] = pc->prefix[0];
+ if (pc->len == 1) {
+ n4->values[0] = pc->child;
+ free(pc);
+ } else {
+ memmove(pc->prefix, pc->prefix + 1, pc->len - 1);
+ pc->len--;
+ n4->values[0] = *v;
+ }
+
+ n4->keys[1] = *kb;
+ if (!_insert(rt, n4->values + 1, kb + 1, ke, rv)) {
+ free(n4);
+ return false;
+ }
+
+ n4->nr_entries = 2;
+
+ v->type = NODE4;
+ v->value.ptr = n4;
+ }
+
+ return true;
+}
+
+static bool _insert_node4(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ struct node4 *n4 = v->value.ptr;
+ if (n4->nr_entries == 4) {
+ struct node16 *n16 = zalloc(sizeof(*n16));
+ if (!n16)
+ return false;
+
+ n16->nr_entries = 5;
+ memcpy(n16->keys, n4->keys, sizeof(n4->keys));
+ memcpy(n16->values, n4->values, sizeof(n4->values));
+
+ n16->keys[4] = *kb;
+ if (!_insert(rt, n16->values + 4, kb + 1, ke, rv)) {
+ free(n16);
+ return false;
+ }
+ free(n4);
+ v->type = NODE16;
+ v->value.ptr = n16;
+ } else {
+ if (!_insert(rt, n4->values + n4->nr_entries, kb + 1, ke, rv))
+ return false;
+
+ n4->keys[n4->nr_entries] = *kb;
+ n4->nr_entries++;
+ }
+ return true;
+}
+
+static bool _insert_node16(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ struct node16 *n16 = v->value.ptr;
+
+ if (n16->nr_entries == 16) {
+ unsigned i;
+ struct node48 *n48 = zalloc(sizeof(*n48));
+
+ if (!n48)
+ return false;
+
+ n48->nr_entries = 17;
+ memset(n48->keys, 48, sizeof(n48->keys));
+
+ for (i = 0; i < 16; i++) {
+ n48->keys[n16->keys[i]] = i;
+ n48->values[i] = n16->values[i];
+ }
+
+ n48->keys[*kb] = 16;
+ if (!_insert(rt, n48->values + 16, kb + 1, ke, rv)) {
+ free(n48);
+ return false;
+ }
+
+ free(n16);
+ v->type = NODE48;
+ v->value.ptr = n48;
+ } else {
+ if (!_insert(rt, n16->values + n16->nr_entries, kb + 1, ke, rv))
+ return false;
+ n16->keys[n16->nr_entries] = *kb;
+ n16->nr_entries++;
+ }
+
+ return true;
+}
+
+static bool _insert_node48(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ struct node48 *n48 = v->value.ptr;
+ if (n48->nr_entries == 48) {
+ unsigned i;
+ struct node256 *n256 = zalloc(sizeof(*n256));
+ if (!n256)
+ return false;
+
+ n256->nr_entries = 49;
+ for (i = 0; i < 256; i++) {
+ if (n48->keys[i] < 48)
+ n256->values[i] = n48->values[n48->keys[i]];
+ }
+
+ if (!_insert(rt, n256->values + *kb, kb + 1, ke, rv)) {
+ free(n256);
+ return false;
+ }
+
+ free(n48);
+ v->type = NODE256;
+ v->value.ptr = n256;
+
+ } else {
+ if (!_insert(rt, n48->values + n48->nr_entries, kb + 1, ke, rv))
+ return false;
+
+ n48->keys[*kb] = n48->nr_entries;
+ n48->nr_entries++;
+ }
+
+ return true;
+}
+
+static bool _insert_node256(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ struct node256 *n256 = v->value.ptr;
+ bool r, was_unset = n256->values[*kb].type == UNSET;
+
+ r = _insert(rt, n256->values + *kb, kb + 1, ke, rv);
+ if (r && was_unset)
+ n256->nr_entries++;
+
+ return r;
+}
+
+// FIXME: the tree should not be touched if insert fails (eg, OOM)
+static bool _insert(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ if (kb == ke) {
+ if (v->type == UNSET) {
+ v->type = VALUE;
+ v->value = rv;
+ rt->nr_entries++;
+
+ } else if (v->type == VALUE) {
+ v->value = rv;
+
+ } else {
+ struct value_chain *vc = zalloc(sizeof(*vc));
+ if (!vc)
+ return false;
+
+ vc->value = rv;
+ vc->child = *v;
+ v->type = VALUE_CHAIN;
+ v->value.ptr = vc;
+ rt->nr_entries++;
+ }
+ return true;
+ }
+
+ switch (v->type) {
+ case UNSET:
+ return _insert_unset(rt, v, kb, ke, rv);
+
+ case VALUE:
+ return _insert_value(rt, v, kb, ke, rv);
+
+ case VALUE_CHAIN:
+ return _insert_value_chain(rt, v, kb, ke, rv);
+
+ case PREFIX_CHAIN:
+ return _insert_prefix_chain(rt, v, kb, ke, rv);
+
+ case NODE4:
+ return _insert_node4(rt, v, kb, ke, rv);
+
+ case NODE16:
+ return _insert_node16(rt, v, kb, ke, rv);
+
+ case NODE48:
+ return _insert_node48(rt, v, kb, ke, rv);
+
+ case NODE256:
+ return _insert_node256(rt, v, kb, ke, rv);
+ }
+
+ // can't get here
+ return false;
+}
+
+struct lookup_result {
+ struct value *v;
+ uint8_t *kb;
+};
+
+static struct lookup_result _lookup_prefix(struct value *v, uint8_t *kb, uint8_t *ke)
+{
+ unsigned i;
+ struct value_chain *vc;
+ struct prefix_chain *pc;
+ struct node4 *n4;
+ struct node16 *n16;
+ struct node48 *n48;
+ struct node256 *n256;
+
+ if (kb == ke)
+ return (struct lookup_result) {.v = v, .kb = kb};
+
+ switch (v->type) {
+ case UNSET:
+ case VALUE:
+ break;
+
+ case VALUE_CHAIN:
+ vc = v->value.ptr;
+ return _lookup_prefix(&vc->child, kb, ke);
+
+ case PREFIX_CHAIN:
+ pc = v->value.ptr;
+ if (ke - kb < pc->len)
+ return (struct lookup_result) {.v = v, .kb = kb};
+
+ for (i = 0; i < pc->len; i++)
+ if (kb[i] != pc->prefix[i])
+ return (struct lookup_result) {.v = v, .kb = kb};
+
+ return _lookup_prefix(&pc->child, kb + pc->len, ke);
+
+ case NODE4:
+ n4 = v->value.ptr;
+ for (i = 0; i < n4->nr_entries; i++)
+ if (n4->keys[i] == *kb)
+ return _lookup_prefix(n4->values + i, kb + 1, ke);
+ break;
+
+ case NODE16:
+ // FIXME: use binary search or simd?
+ n16 = v->value.ptr;
+ for (i = 0; i < n16->nr_entries; i++)
+ if (n16->keys[i] == *kb)
+ return _lookup_prefix(n16->values + i, kb + 1, ke);
+ break;
+
+ case NODE48:
+ n48 = v->value.ptr;
+ i = n48->keys[*kb];
+ if (i < 48)
+ return _lookup_prefix(n48->values + i, kb + 1, ke);
+ break;
+
+ case NODE256:
+ n256 = v->value.ptr;
+ if (n256->values[*kb].type != UNSET)
+ return _lookup_prefix(n256->values + *kb, kb + 1, ke);
+ break;
+ }
+
+ return (struct lookup_result) {.v = v, .kb = kb};
+}
+
+bool radix_tree_insert(struct radix_tree *rt, uint8_t *kb, uint8_t *ke, union radix_value rv)
+{
+ struct lookup_result lr = _lookup_prefix(&rt->root, kb, ke);
+ return _insert(rt, lr.v, lr.kb, ke, rv);
+}
+
+// Note the degrade functions also free the original node.
+static void _degrade_to_n4(struct node16 *n16, struct value *result)
+{
+ struct node4 *n4 = zalloc(sizeof(*n4));
+
+ n4->nr_entries = n16->nr_entries;
+ memcpy(n4->keys, n16->keys, n16->nr_entries * sizeof(*n4->keys));
+ memcpy(n4->values, n16->values, n16->nr_entries * sizeof(*n4->values));
+ free(n16);
+
+ result->type = NODE4;
+ result->value.ptr = n4;
+}
+
+static void _degrade_to_n16(struct node48 *n48, struct value *result)
+{
+ unsigned i, count = 0;
+ struct node16 *n16 = zalloc(sizeof(*n16));
+
+ n16->nr_entries = n48->nr_entries;
+ for (i = 0; i < 256; i++) {
+ if (n48->keys[i] < 48) {
+ n16->keys[count] = i;
+ count++;
+ }
+ }
+
+ memcpy(n16->values, n48->values, n48->nr_entries * sizeof(*n16->values));
+
+ free(n48);
+
+ result->type = NODE16;
+ result->value.ptr = n16;
+}
+
+static void _degrade_to_n48(struct node256 *n256, struct value *result)
+{
+ unsigned i, count = 0;
+ struct node48 *n48 = zalloc(sizeof(*n48));
+
+ memset(n48->keys, 48, sizeof(n48->keys));
+
+ n48->nr_entries = n256->nr_entries;
+ for (i = 0; i < 256; i++) {
+ if (n256->values[i].type == UNSET)
+ continue;
+
+ n48->keys[i] = count;
+ n48->values[count] = n256->values[i];
+ count++;
+ }
+
+ free(n256);
+
+ result->type = NODE48;
+ result->value.ptr = n48;
+}
+
+// Removes an entry in an array by sliding the values above it down.
+static void _erase_elt(void *array, unsigned obj_size, unsigned count, unsigned index)
+{
+ if (index == (count - 1))
+ // The simple case
+ return;
+
+ memmove(((uint8_t *) array) + (obj_size * index),
+ ((uint8_t *) array) + (obj_size * (index + 1)),
+ obj_size * (count - index - 1));
+
+ // Zero the now unused last elt (set's v.type to UNSET)
+ memset(((uint8_t *) array) + (count - 1) * obj_size, 0, obj_size);
+}
+
+static bool _remove(struct radix_tree *rt, struct value *root, uint8_t *kb, uint8_t *ke)
+{
+ bool r;
+ unsigned i, j;
+ struct value_chain *vc;
+ struct prefix_chain *pc;
+ struct node4 *n4;
+ struct node16 *n16;
+ struct node48 *n48;
+ struct node256 *n256;
+
+ if (kb == ke) {
+ if (root->type == VALUE) {
+ root->type = UNSET;
+ _dtr(rt, root->value);
+ return true;
+
+ } else if (root->type == VALUE_CHAIN) {
+ vc = root->value.ptr;
+ _dtr(rt, vc->value);
+ memcpy(root, &vc->child, sizeof(*root));
+ free(vc);
+ return true;
+
+ } else
+ return false;
+ }
+
+ switch (root->type) {
+ case UNSET:
+ case VALUE:
+ // this is a value for a prefix of the key
+ return false;
+
+ case VALUE_CHAIN:
+ vc = root->value.ptr;
+ r = _remove(rt, &vc->child, kb, ke);
+ if (r && (vc->child.type == UNSET)) {
+ root->type = VALUE;
+ root->value = vc->value;
+ free(vc);
+ }
+ return r;
+
+ case PREFIX_CHAIN:
+ pc = root->value.ptr;
+ if (ke - kb < pc->len)
+ return false;
+
+ for (i = 0; i < pc->len; i++)
+ if (kb[i] != pc->prefix[i])
+ return false;
+
+ r = _remove(rt, &pc->child, kb + pc->len, ke);
+ if (r && pc->child.type == UNSET) {
+ root->type = UNSET;
+ free(pc);
+ }
+ return r;
+
+ case NODE4:
+ n4 = root->value.ptr;
+ for (i = 0; i < n4->nr_entries; i++) {
+ if (n4->keys[i] == *kb) {
+ r = _remove(rt, n4->values + i, kb + 1, ke);
+ if (r && n4->values[i].type == UNSET) {
+ if (i < n4->nr_entries) {
+ _erase_elt(n4->keys, sizeof(*n4->keys), n4->nr_entries, i);
+ _erase_elt(n4->values, sizeof(*n4->values), n4->nr_entries, i);
+ }
+
+ n4->nr_entries--;
+ if (!n4->nr_entries) {
+ free(n4);
+ root->type = UNSET;
+ }
+ }
+ return r;
+ }
+ }
+ return false;
+
+ case NODE16:
+ n16 = root->value.ptr;
+ for (i = 0; i < n16->nr_entries; i++) {
+ if (n16->keys[i] == *kb) {
+ r = _remove(rt, n16->values + i, kb + 1, ke);
+ if (r && n16->values[i].type == UNSET) {
+ if (i < n16->nr_entries) {
+ _erase_elt(n16->keys, sizeof(*n16->keys), n16->nr_entries, i);
+ _erase_elt(n16->values, sizeof(*n16->values), n16->nr_entries, i);
+ }
+
+ n16->nr_entries--;
+ if (n16->nr_entries <= 4) {
+ _degrade_to_n4(n16, root);
+ }
+ }
+ return r;
+ }
+ }
+ return false;
+
+ case NODE48:
+ n48 = root->value.ptr;
+ i = n48->keys[*kb];
+ if (i < 48) {
+ r = _remove(rt, n48->values + i, kb + 1, ke);
+ if (r && n48->values[i].type == UNSET) {
+ n48->keys[*kb] = 48;
+ for (j = 0; j < 256; j++)
+ if (n48->keys[j] < 48 && n48->keys[j] > i)
+ n48->keys[j]--;
+ _erase_elt(n48->values, sizeof(*n48->values), n48->nr_entries, i);
+ n48->nr_entries--;
+ if (n48->nr_entries <= 16)
+ _degrade_to_n16(n48, root);
+ }
+ return r;
+ }
+ return false;
+
+ case NODE256:
+ n256 = root->value.ptr;
+ r = _remove(rt, n256->values + (*kb), kb + 1, ke);
+ if (r && n256->values[*kb].type == UNSET) {
+ n256->nr_entries--;
+ if (n256->nr_entries <= 48)
+ _degrade_to_n48(n256, root);
+ }
+ return r;
+ }
+
+ return false;
+}
+
+bool radix_tree_remove(struct radix_tree *rt, uint8_t *key_begin, uint8_t *key_end)
+{
+ if (_remove(rt, &rt->root, key_begin, key_end)) {
+ rt->nr_entries--;
+ return true;
+ }
+
+ return false;
+}
+
+//----------------------------------------------------------------
+
+static bool _prefix_chain_matches(struct lookup_result *lr, uint8_t *ke)
+{
+ // It's possible the top node is a prefix chain, and
+ // the remaining key matches part of it.
+ if (lr->v->type == PREFIX_CHAIN) {
+ unsigned i, rlen = ke - lr->kb;
+ struct prefix_chain *pc = lr->v->value.ptr;
+ if (rlen < pc->len) {
+ for (i = 0; i < rlen; i++)
+ if (pc->prefix[i] != lr->kb[i])
+ return false;
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static bool _remove_subtree(struct radix_tree *rt, struct value *root, uint8_t *kb, uint8_t *ke, unsigned *count)
+{
+ bool r;
+ unsigned i, j, len;
+ struct value_chain *vc;
+ struct prefix_chain *pc;
+ struct node4 *n4;
+ struct node16 *n16;
+ struct node48 *n48;
+ struct node256 *n256;
+
+ if (kb == ke) {
+ *count += _free_node(rt, *root);
+ root->type = UNSET;
+ return true;
+ }
+
+ switch (root->type) {
+ case UNSET:
+ case VALUE:
+ // No entries with the given prefix
+ return true;
+
+ case VALUE_CHAIN:
+ vc = root->value.ptr;
+ r = _remove_subtree(rt, &vc->child, kb, ke, count);
+ if (r && (vc->child.type == UNSET)) {
+ root->type = VALUE;
+ root->value = vc->value;
+ free(vc);
+ }
+ return r;
+
+ case PREFIX_CHAIN:
+ pc = root->value.ptr;
+ len = min(pc->len, ke - kb);
+ for (i = 0; i < len; i++)
+ if (kb[i] != pc->prefix[i])
+ return true;
+
+ r = _remove_subtree(rt, &pc->child, len < pc->len ? ke : (kb + pc->len), ke, count);
+ if (r && pc->child.type == UNSET) {
+ root->type = UNSET;
+ free(pc);
+ }
+ return r;
+
+ case NODE4:
+ n4 = root->value.ptr;
+ for (i = 0; i < n4->nr_entries; i++) {
+ if (n4->keys[i] == *kb) {
+ r = _remove_subtree(rt, n4->values + i, kb + 1, ke, count);
+ if (r && n4->values[i].type == UNSET) {
+ if (i < n4->nr_entries) {
+ _erase_elt(n4->keys, sizeof(*n4->keys), n4->nr_entries, i);
+ _erase_elt(n4->values, sizeof(*n4->values), n4->nr_entries, i);
+ }
+
+ n4->nr_entries--;
+ if (!n4->nr_entries) {
+ free(n4);
+ root->type = UNSET;
+ }
+ }
+ return r;
+ }
+ }
+ return true;
+
+ case NODE16:
+ n16 = root->value.ptr;
+ for (i = 0; i < n16->nr_entries; i++) {
+ if (n16->keys[i] == *kb) {
+ r = _remove_subtree(rt, n16->values + i, kb + 1, ke, count);
+ if (r && n16->values[i].type == UNSET) {
+ if (i < n16->nr_entries) {
+ _erase_elt(n16->keys, sizeof(*n16->keys), n16->nr_entries, i);
+ _erase_elt(n16->values, sizeof(*n16->values), n16->nr_entries, i);
+ }
+
+ n16->nr_entries--;
+ if (n16->nr_entries <= 4)
+ _degrade_to_n4(n16, root);
+ }
+ return r;
+ }
+ }
+ return true;
+
+ case NODE48:
+ n48 = root->value.ptr;
+ i = n48->keys[*kb];
+ if (i < 48) {
+ r = _remove_subtree(rt, n48->values + i, kb + 1, ke, count);
+ if (r && n48->values[i].type == UNSET) {
+ n48->keys[*kb] = 48;
+ for (j = 0; j < 256; j++)
+ if (n48->keys[j] < 48 && n48->keys[j] > i)
+ n48->keys[j]--;
+ _erase_elt(n48->values, sizeof(*n48->values), n48->nr_entries, i);
+ n48->nr_entries--;
+ if (n48->nr_entries <= 16)
+ _degrade_to_n16(n48, root);
+ }
+ return r;
+ }
+ return true;
+
+ case NODE256:
+ n256 = root->value.ptr;
+ if (n256->values[*kb].type == UNSET)
+ return true; // No entries
+
+ r = _remove_subtree(rt, n256->values + (*kb), kb + 1, ke, count);
+ if (r && n256->values[*kb].type == UNSET) {
+ n256->nr_entries--;
+ if (n256->nr_entries <= 48)
+ _degrade_to_n48(n256, root);
+ }
+ return r;
+ }
+
+ // Shouldn't get here
+ return false;
+}
+
+unsigned radix_tree_remove_prefix(struct radix_tree *rt, uint8_t *kb, uint8_t *ke)
+{
+ unsigned count = 0;
+
+ if (_remove_subtree(rt, &rt->root, kb, ke, &count))
+ rt->nr_entries -= count;
+
+ return count;
+}
+
+//----------------------------------------------------------------
+
+bool radix_tree_lookup(struct radix_tree *rt,
+ uint8_t *kb, uint8_t *ke, union radix_value *result)
+{
+ struct value_chain *vc;
+ struct lookup_result lr = _lookup_prefix(&rt->root, kb, ke);
+ if (lr.kb == ke) {
+ switch (lr.v->type) {
+ case VALUE:
+ *result = lr.v->value;
+ return true;
+
+ case VALUE_CHAIN:
+ vc = lr.v->value.ptr;
+ *result = vc->value;
+ return true;
+
+ default:
+ return false;
+ }
+ }
+
+ return false;
+}
+
+// FIXME: build up the keys too
+static bool _iterate(struct value *v, struct radix_tree_iterator *it)
+{
+ unsigned i;
+ struct value_chain *vc;
+ struct prefix_chain *pc;
+ struct node4 *n4;
+ struct node16 *n16;
+ struct node48 *n48;
+ struct node256 *n256;
+
+ switch (v->type) {
+ case UNSET:
+ // can't happen
+ break;
+
+ case VALUE:
+ return it->visit(it, NULL, NULL, v->value);
+
+ case VALUE_CHAIN:
+ vc = v->value.ptr;
+ return it->visit(it, NULL, NULL, vc->value) && _iterate(&vc->child, it);
+
+ case PREFIX_CHAIN:
+ pc = v->value.ptr;
+ return _iterate(&pc->child, it);
+
+ case NODE4:
+ n4 = (struct node4 *) v->value.ptr;
+ for (i = 0; i < n4->nr_entries; i++)
+ if (!_iterate(n4->values + i, it))
+ return false;
+ return true;
+
+ case NODE16:
+ n16 = (struct node16 *) v->value.ptr;
+ for (i = 0; i < n16->nr_entries; i++)
+ if (!_iterate(n16->values + i, it))
+ return false;
+ return true;
+
+ case NODE48:
+ n48 = (struct node48 *) v->value.ptr;
+ for (i = 0; i < n48->nr_entries; i++)
+ if (!_iterate(n48->values + i, it))
+ return false;
+ return true;
+
+ case NODE256:
+ n256 = (struct node256 *) v->value.ptr;
+ for (i = 0; i < 256; i++)
+ if (n256->values[i].type != UNSET && !_iterate(n256->values + i, it))
+ return false;
+ return true;
+ }
+
+ // can't get here
+ return false;
+}
+
+void radix_tree_iterate(struct radix_tree *rt, uint8_t *kb, uint8_t *ke,
+ struct radix_tree_iterator *it)
+{
+ struct lookup_result lr = _lookup_prefix(&rt->root, kb, ke);
+ if (lr.kb == ke || _prefix_chain_matches(&lr, ke))
+ _iterate(lr.v, it);
+}
+
+//----------------------------------------------------------------
+// Checks:
+// 1) The number of entries matches rt->nr_entries
+// 2) The number of entries is correct in each node
+// 3) prefix chain len > 0
+// 4) all unused values are UNSET
+
+static bool _check_nodes(struct value *v, unsigned *count)
+{
+ unsigned i, ncount;
+ struct value_chain *vc;
+ struct prefix_chain *pc;
+ struct node4 *n4;
+ struct node16 *n16;
+ struct node48 *n48;
+ struct node256 *n256;
+
+ switch (v->type) {
+ case UNSET:
+ return true;
+
+ case VALUE:
+ (*count)++;
+ return true;
+
+ case VALUE_CHAIN:
+ (*count)++;
+ vc = v->value.ptr;
+ return _check_nodes(&vc->child, count);
+
+ case PREFIX_CHAIN:
+ pc = v->value.ptr;
+ return _check_nodes(&pc->child, count);
+
+ case NODE4:
+ n4 = v->value.ptr;
+ for (i = 0; i < n4->nr_entries; i++)
+ if (!_check_nodes(n4->values + i, count))
+ return false;
+
+ for (i = n4->nr_entries; i < 4; i++)
+ if (n4->values[i].type != UNSET) {
+ fprintf(stderr, "unused value is not UNSET (n4)\n");
+ return false;
+ }
+
+ return true;
+
+ case NODE16:
+ n16 = v->value.ptr;
+ for (i = 0; i < n16->nr_entries; i++)
+ if (!_check_nodes(n16->values + i, count))
+ return false;
+
+ for (i = n16->nr_entries; i < 16; i++)
+ if (n16->values[i].type != UNSET) {
+ fprintf(stderr, "unused value is not UNSET (n16)\n");
+ return false;
+ }
+
+ return true;
+
+ case NODE48:
+ n48 = v->value.ptr;
+ ncount = 0;
+ for (i = 0; i < 256; i++) {
+ if (n48->keys[i] < 48) {
+ ncount++;
+ if (!_check_nodes(n48->values + n48->keys[i], count))
+ return false;
+ }
+ }
+
+ if (ncount != n48->nr_entries) {
+ fprintf(stderr, "incorrect number of entries in n48, n48->nr_entries = %u, actual = %u\n",
+ n48->nr_entries, ncount);
+ return false;
+ }
+
+ for (i = n48->nr_entries; i < 48; i++)
+ if (n48->values[i].type != UNSET) {
+ fprintf(stderr, "unused value is not UNSET (n48)\n");
+ return false;
+ }
+
+ return true;
+
+ case NODE256:
+ n256 = v->value.ptr;
+
+ ncount = 0;
+ for (i = 0; i < 256; i++) {
+ struct value *v2 = n256->values + i;
+
+ if (v2->type == UNSET)
+ continue;
+
+ if (!_check_nodes(v2, count))
+ return false;
+
+ ncount++;
+ }
+
+ if (ncount != n256->nr_entries) {
+ fprintf(stderr, "incorrect number of entries in n256, n256->nr_entries = %u, actual = %u\n",
+ n256->nr_entries, ncount);
+ return false;
+ }
+
+ return true;
+
+ default:
+ fprintf(stderr, "unknown value type: %u\n", v->type);
+ }
+
+ fprintf(stderr, "shouldn't get here\n");
+ return false;
+}
+
+bool radix_tree_is_well_formed(struct radix_tree *rt)
+{
+ unsigned count = 0;
+
+ if (!_check_nodes(&rt->root, &count))
+ return false;
+
+ if (rt->nr_entries != count) {
+ fprintf(stderr, "incorrect entry count: rt->nr_entries = %u, actual = %u\n",
+ rt->nr_entries, count);
+ return false;
+ }
+
+ return true;
+}
+
+//----------------------------------------------------------------
+
+static void _dump(FILE *out, struct value v, unsigned indent)
+{
+ unsigned i;
+ struct value_chain *vc;
+ struct prefix_chain *pc;
+ struct node4 *n4;
+ struct node16 *n16;
+ struct node48 *n48;
+ struct node256 *n256;
+
+ if (v.type == UNSET)
+ return;
+
+ for (i = 0; i < 2 * indent; i++)
+ fprintf(out, " ");
+
+ switch (v.type) {
+ case UNSET:
+ // can't happen
+ break;
+
+ case VALUE:
+ fprintf(out, "<val: %llu>\n", (unsigned long long) v.value.n);
+ break;
+
+ case VALUE_CHAIN:
+ vc = v.value.ptr;
+ fprintf(out, "<val_chain: %llu>\n", (unsigned long long) vc->value.n);
+ _dump(out, vc->child, indent + 1);
+ break;
+
+ case PREFIX_CHAIN:
+ pc = v.value.ptr;
+ fprintf(out, "<prefix: ");
+ for (i = 0; i < pc->len; i++)
+ fprintf(out, "%x.", (unsigned) *(pc->prefix + i));
+ fprintf(out, ">\n");
+ _dump(out, pc->child, indent + 1);
+ break;
+
+ case NODE4:
+ n4 = v.value.ptr;
+ fprintf(out, "<n4: ");
+ for (i = 0; i < n4->nr_entries; i++)
+ fprintf(out, "%x ", (unsigned) n4->keys[i]);
+ fprintf(out, ">\n");
+
+ for (i = 0; i < n4->nr_entries; i++)
+ _dump(out, n4->values[i], indent + 1);
+ break;
+
+ case NODE16:
+ n16 = v.value.ptr;
+ fprintf(out, "<n16: ");
+ for (i = 0; i < n16->nr_entries; i++)
+ fprintf(out, "%x ", (unsigned) n16->keys[i]);
+ fprintf(out, ">\n");
+
+ for (i = 0; i < n16->nr_entries; i++)
+ _dump(out, n16->values[i], indent + 1);
+ break;
+
+ case NODE48:
+ n48 = v.value.ptr;
+ fprintf(out, "<n48: ");
+ for (i = 0; i < 256; i++)
+ if (n48->keys[i] < 48)
+ fprintf(out, "%x ", i);
+ fprintf(out, ">\n");
+
+ for (i = 0; i < 256; i++)
+ if (n48->keys[i] < 48)
+ _dump(out, n48->values[i], indent + 1);
+ break;
+
+ case NODE256:
+ n256 = v.value.ptr;
+ fprintf(out, "<n256: ");
+ for (i = 0; i < 256; i++)
+ if (n256->values[i].type != UNSET)
+ fprintf(out, "%x ", i);
+ fprintf(out, ">\n");
+
+ for (i = 0; i < 256; i++)
+ if (n256->values[i].type != UNSET)
+ _dump(out, n256->values[i], indent + 1);
+ break;
+ }
+}
+
+void radix_tree_dump(struct radix_tree *rt, FILE *out)
+{
+ _dump(out, rt->root, 0);
+}
+
+//----------------------------------------------------------------
diff --git a/base/data-struct/radix-tree-simple.c b/base/data-struct/radix-tree-simple.c
new file mode 100644
index 0000000..e8a2fdd
--- /dev/null
+++ b/base/data-struct/radix-tree-simple.c
@@ -0,0 +1,256 @@
+// Copyright (C) 2018 Red Hat, Inc. All rights reserved.
+//
+// This file is part of LVM2.
+//
+// This copyrighted material is made available to anyone wishing to use,
+// modify, copy, or redistribute it subject to the terms and conditions
+// of the GNU Lesser General Public License v.2.1.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program; if not, write to the Free Software Foundation,
+// Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+#include "radix-tree.h"
+
+#include "base/memory/container_of.h"
+#include "base/memory/zalloc.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+//----------------------------------------------------------------
+// This implementation is based around nested binary trees. Very
+// simple (and hopefully correct).
+
+struct node {
+ struct node *left;
+ struct node *right;
+
+ uint8_t key;
+ struct node *center;
+
+ bool has_value;
+ union radix_value value;
+};
+
+struct radix_tree {
+ radix_value_dtr dtr;
+ void *dtr_context;
+
+ struct node *root;
+};
+
+struct radix_tree *
+radix_tree_create(radix_value_dtr dtr, void *dtr_context)
+{
+ struct radix_tree *rt = zalloc(sizeof(*rt));
+
+ if (rt) {
+ rt->dtr = dtr;
+ rt->dtr_context = dtr_context;
+ }
+
+ return rt;
+}
+
+// Returns the number of entries in the tree
+static unsigned _destroy_tree(struct node *n, radix_value_dtr dtr, void *context)
+{
+ unsigned r;
+
+ if (!n)
+ return 0;
+
+ r = _destroy_tree(n->left, dtr, context);
+ r += _destroy_tree(n->right, dtr, context);
+ r += _destroy_tree(n->center, dtr, context);
+
+ if (n->has_value) {
+ if (dtr)
+ dtr(context, n->value);
+ r++;
+ }
+
+ free(n);
+
+ return r;
+}
+
+void radix_tree_destroy(struct radix_tree *rt)
+{
+ _destroy_tree(rt->root, rt->dtr, rt->dtr_context);
+ free(rt);
+}
+
+static unsigned _count(struct node *n)
+{
+ unsigned r;
+
+ if (!n)
+ return 0;
+
+ r = _count(n->left);
+ r += _count(n->right);
+ r += _count(n->center);
+
+ if (n->has_value)
+ r++;
+
+ return r;
+}
+
+unsigned radix_tree_size(struct radix_tree *rt)
+{
+ return _count(rt->root);
+}
+
+static struct node **_lookup(struct node **pn, uint8_t *kb, uint8_t *ke)
+{
+ struct node *n = *pn;
+
+ if (!n || (kb == ke))
+ return pn;
+
+ if (*kb < n->key)
+ return _lookup(&n->left, kb, ke);
+
+ else if (*kb > n->key)
+ return _lookup(&n->right, kb, ke);
+
+ else
+ return _lookup(&n->center, kb + 1, ke);
+}
+
+static bool _insert(struct node **pn, uint8_t *kb, uint8_t *ke, union radix_value v)
+{
+ struct node *n = *pn;
+
+ if (!n) {
+ n = zalloc(sizeof(*n));
+ if (!n)
+ return false;
+
+ n->key = *kb;
+ *pn = n;
+ }
+
+ if (kb == ke) {
+ n->has_value = true;
+ n->value = v;
+ return true;
+ }
+
+ if (*kb < n->key)
+ return _insert(&n->left, kb, ke, v);
+
+ else if (*kb > n->key)
+ return _insert(&n->right, kb, ke, v);
+
+ else
+ return _insert(&n->center, kb + 1, ke, v);
+}
+
+bool radix_tree_insert(struct radix_tree *rt, uint8_t *kb, uint8_t *ke, union radix_value v)
+{
+ return _insert(&rt->root, kb, ke, v);
+}
+
+bool radix_tree_remove(struct radix_tree *rt, uint8_t *kb, uint8_t *ke)
+{
+ struct node **pn = _lookup(&rt->root, kb, ke);
+ struct node *n = *pn;
+
+ if (!n || !n->has_value)
+ return false;
+
+ else {
+ if (rt->dtr)
+ rt->dtr(rt->dtr_context, n->value);
+
+ if (n->left || n->center || n->right) {
+ n->has_value = false;
+ return true;
+
+ } else {
+ // FIXME: delete parent if this was the last entry
+ free(n);
+ *pn = NULL;
+ }
+
+ return true;
+ }
+}
+
+unsigned radix_tree_remove_prefix(struct radix_tree *rt, uint8_t *kb, uint8_t *ke)
+{
+ struct node **pn;
+ unsigned count;
+
+ pn = _lookup(&rt->root, kb, ke);
+
+ if (*pn) {
+ count = _destroy_tree(*pn, rt->dtr, rt->dtr_context);
+ *pn = NULL;
+ }
+
+ return count;
+}
+
+bool
+radix_tree_lookup(struct radix_tree *rt, uint8_t *kb, uint8_t *ke, union radix_value *result)
+{
+ struct node **pn = _lookup(&rt->root, kb, ke);
+ struct node *n = *pn;
+
+ if (n && n->has_value) {
+ *result = n->value;
+ return true;
+ } else
+ return false;
+}
+
+static void _iterate(struct node *n, struct radix_tree_iterator *it)
+{
+ if (!n)
+ return;
+
+ _iterate(n->left, it);
+
+ if (n->has_value)
+ // FIXME: fill out the key
+ it->visit(it, NULL, NULL, n->value);
+
+ _iterate(n->center, it);
+ _iterate(n->right, it);
+}
+
+void radix_tree_iterate(struct radix_tree *rt, uint8_t *kb, uint8_t *ke,
+ struct radix_tree_iterator *it)
+{
+ if (kb == ke)
+ _iterate(rt->root, it);
+
+ else {
+ struct node **pn = _lookup(&rt->root, kb, ke);
+ struct node *n = *pn;
+
+ if (n) {
+ if (n->has_value)
+ it->visit(it, NULL, NULL, n->value);
+ _iterate(n->center, it);
+ }
+ }
+}
+
+bool radix_tree_is_well_formed(struct radix_tree *rt)
+{
+ return true;
+}
+
+void radix_tree_dump(struct radix_tree *rt, FILE *out)
+{
+}
+
+//----------------------------------------------------------------
+
diff --git a/base/data-struct/radix-tree.c b/base/data-struct/radix-tree.c
index 1eef1f8..52a1a05 100644
--- a/base/data-struct/radix-tree.c
+++ b/base/data-struct/radix-tree.c
@@ -10,1253 +10,12 @@
// along with this program; if not, write to the Free Software Foundation,
// Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
-#include "radix-tree.h"
-
-#include "base/memory/container_of.h"
-#include "base/memory/zalloc.h"
-
-#include <assert.h>
-#include <stdlib.h>
-#include <stdio.h>
-
//----------------------------------------------------------------
-enum node_type {
- UNSET = 0,
- VALUE,
- VALUE_CHAIN,
- PREFIX_CHAIN,
- NODE4,
- NODE16,
- NODE48,
- NODE256
-};
-
-struct value {
- enum node_type type;
- union radix_value value;
-};
-
-// This is used for entries that have a key which is a prefix of another key.
-struct value_chain {
- union radix_value value;
- struct value child;
-};
-
-struct prefix_chain {
- struct value child;
- unsigned len;
- uint8_t prefix[0];
-};
-
-struct node4 {
- uint32_t nr_entries;
- uint8_t keys[4];
- struct value values[4];
-};
-
-struct node16 {
- uint32_t nr_entries;
- uint8_t keys[16];
- struct value values[16];
-};
-
-struct node48 {
- uint32_t nr_entries;
- uint8_t keys[256];
- struct value values[48];
-};
-
-struct node256 {
- uint32_t nr_entries;
- struct value values[256];
-};
-
-struct radix_tree {
- unsigned nr_entries;
- struct value root;
- radix_value_dtr dtr;
- void *dtr_context;
-};
-
-//----------------------------------------------------------------
-
-struct radix_tree *radix_tree_create(radix_value_dtr dtr, void *dtr_context)
-{
- struct radix_tree *rt = malloc(sizeof(*rt));
-
- if (rt) {
- rt->nr_entries = 0;
- rt->root.type = UNSET;
- rt->dtr = dtr;
- rt->dtr_context = dtr_context;
- }
-
- return rt;
-}
-
-static inline void _dtr(struct radix_tree *rt, union radix_value v)
-{
- if (rt->dtr)
- rt->dtr(rt->dtr_context, v);
-}
-
-// Returns the number of values removed
-static unsigned _free_node(struct radix_tree *rt, struct value v)
-{
- unsigned i, nr = 0;
- struct value_chain *vc;
- struct prefix_chain *pc;
- struct node4 *n4;
- struct node16 *n16;
- struct node48 *n48;
- struct node256 *n256;
-
- switch (v.type) {
- case UNSET:
- break;
-
- case VALUE:
- _dtr(rt, v.value);
- nr = 1;
- break;
-
- case VALUE_CHAIN:
- vc = v.value.ptr;
- _dtr(rt, vc->value);
- nr = 1 + _free_node(rt, vc->child);
- free(vc);
- break;
-
- case PREFIX_CHAIN:
- pc = v.value.ptr;
- nr = _free_node(rt, pc->child);
- free(pc);
- break;
-
- case NODE4:
- n4 = (struct node4 *) v.value.ptr;
- for (i = 0; i < n4->nr_entries; i++)
- nr += _free_node(rt, n4->values[i]);
- free(n4);
- break;
-
- case NODE16:
- n16 = (struct node16 *) v.value.ptr;
- for (i = 0; i < n16->nr_entries; i++)
- nr += _free_node(rt, n16->values[i]);
- free(n16);
- break;
-
- case NODE48:
- n48 = (struct node48 *) v.value.ptr;
- for (i = 0; i < n48->nr_entries; i++)
- nr += _free_node(rt, n48->values[i]);
- free(n48);
- break;
-
- case NODE256:
- n256 = (struct node256 *) v.value.ptr;
- for (i = 0; i < 256; i++)
- nr += _free_node(rt, n256->values[i]);
- free(n256);
- break;
- }
-
- return nr;
-}
-
-void radix_tree_destroy(struct radix_tree *rt)
-{
- _free_node(rt, rt->root);
- free(rt);
-}
-
-unsigned radix_tree_size(struct radix_tree *rt)
-{
- return rt->nr_entries;
-}
-
-static bool _insert(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv);
-
-static bool _insert_unset(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- unsigned len = ke - kb;
-
- if (!len) {
- // value
- v->type = VALUE;
- v->value = rv;
- rt->nr_entries++;
- } else {
- // prefix -> value
- struct prefix_chain *pc = zalloc(sizeof(*pc) + len);
- if (!pc)
- return false;
-
- pc->child.type = VALUE;
- pc->child.value = rv;
- pc->len = len;
- memcpy(pc->prefix, kb, len);
- v->type = PREFIX_CHAIN;
- v->value.ptr = pc;
- rt->nr_entries++;
- }
-
- return true;
-}
-
-static bool _insert_value(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- unsigned len = ke - kb;
-
- if (!len)
- // overwrite
- v->value = rv;
-
- else {
- // value_chain -> value
- struct value_chain *vc = zalloc(sizeof(*vc));
- if (!vc)
- return false;
-
- vc->value = v->value;
- if (!_insert(rt, &vc->child, kb, ke, rv)) {
- free(vc);
- return false;
- }
-
- v->type = VALUE_CHAIN;
- v->value.ptr = vc;
- }
-
- return true;
-}
-
-static bool _insert_value_chain(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- struct value_chain *vc = v->value.ptr;
- return _insert(rt, &vc->child, kb, ke, rv);
-}
-
-static unsigned min(unsigned lhs, unsigned rhs)
-{
- if (lhs <= rhs)
- return lhs;
- else
- return rhs;
-}
-
-static bool _insert_prefix_chain(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- struct prefix_chain *pc = v->value.ptr;
-
- if (!pc->len) {
- v->type = VALUE;
- v->value = rv;
-
- } else if (*kb == pc->prefix[0]) {
- // There's a common prefix let's split the chain into two and
- // recurse.
- struct prefix_chain *pc2;
- unsigned i, len = min(pc->len, ke - kb);
-
- for (i = 0; i < len; i++)
- if (kb[i] != pc->prefix[i])
- break;
-
- pc2 = zalloc(sizeof(*pc2) + pc->len - i);
- pc2->len = pc->len - i;
- memmove(pc2->prefix, pc->prefix + i, pc2->len);
- pc2->child = pc->child;
-
- // FIXME: this trashes pc so we can't back out
- pc->child.type = PREFIX_CHAIN;
- pc->child.value.ptr = pc2;
- pc->len = i;
-
- if (!_insert(rt, &pc->child, kb + i, ke, rv)) {
- free(pc2);
- return false;
- }
-
- } else {
- // Stick an n4 in front.
- struct node4 *n4 = zalloc(sizeof(*n4));
- if (!n4)
- return false;
-
- n4->keys[0] = pc->prefix[0];
- if (pc->len == 1) {
- n4->values[0] = pc->child;
- free(pc);
- } else {
- memmove(pc->prefix, pc->prefix + 1, pc->len - 1);
- pc->len--;
- n4->values[0] = *v;
- }
-
- n4->keys[1] = *kb;
- if (!_insert(rt, n4->values + 1, kb + 1, ke, rv)) {
- free(n4);
- return false;
- }
-
- n4->nr_entries = 2;
-
- v->type = NODE4;
- v->value.ptr = n4;
- }
-
- return true;
-}
-
-static bool _insert_node4(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- struct node4 *n4 = v->value.ptr;
- if (n4->nr_entries == 4) {
- struct node16 *n16 = zalloc(sizeof(*n16));
- if (!n16)
- return false;
-
- n16->nr_entries = 5;
- memcpy(n16->keys, n4->keys, sizeof(n4->keys));
- memcpy(n16->values, n4->values, sizeof(n4->values));
-
- n16->keys[4] = *kb;
- if (!_insert(rt, n16->values + 4, kb + 1, ke, rv)) {
- free(n16);
- return false;
- }
- free(n4);
- v->type = NODE16;
- v->value.ptr = n16;
- } else {
- if (!_insert(rt, n4->values + n4->nr_entries, kb + 1, ke, rv))
- return false;
-
- n4->keys[n4->nr_entries] = *kb;
- n4->nr_entries++;
- }
- return true;
-}
-
-static bool _insert_node16(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- struct node16 *n16 = v->value.ptr;
-
- if (n16->nr_entries == 16) {
- unsigned i;
- struct node48 *n48 = zalloc(sizeof(*n48));
-
- if (!n48)
- return false;
-
- n48->nr_entries = 17;
- memset(n48->keys, 48, sizeof(n48->keys));
-
- for (i = 0; i < 16; i++) {
- n48->keys[n16->keys[i]] = i;
- n48->values[i] = n16->values[i];
- }
-
- n48->keys[*kb] = 16;
- if (!_insert(rt, n48->values + 16, kb + 1, ke, rv)) {
- free(n48);
- return false;
- }
-
- free(n16);
- v->type = NODE48;
- v->value.ptr = n48;
- } else {
- if (!_insert(rt, n16->values + n16->nr_entries, kb + 1, ke, rv))
- return false;
- n16->keys[n16->nr_entries] = *kb;
- n16->nr_entries++;
- }
-
- return true;
-}
-
-static bool _insert_node48(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- struct node48 *n48 = v->value.ptr;
- if (n48->nr_entries == 48) {
- unsigned i;
- struct node256 *n256 = zalloc(sizeof(*n256));
- if (!n256)
- return false;
-
- n256->nr_entries = 49;
- for (i = 0; i < 256; i++) {
- if (n48->keys[i] < 48)
- n256->values[i] = n48->values[n48->keys[i]];
- }
-
- if (!_insert(rt, n256->values + *kb, kb + 1, ke, rv)) {
- free(n256);
- return false;
- }
-
- free(n48);
- v->type = NODE256;
- v->value.ptr = n256;
-
- } else {
- if (!_insert(rt, n48->values + n48->nr_entries, kb + 1, ke, rv))
- return false;
-
- n48->keys[*kb] = n48->nr_entries;
- n48->nr_entries++;
- }
-
- return true;
-}
-
-static bool _insert_node256(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- struct node256 *n256 = v->value.ptr;
- bool r, was_unset = n256->values[*kb].type == UNSET;
-
- r = _insert(rt, n256->values + *kb, kb + 1, ke, rv);
- if (r && was_unset)
- n256->nr_entries++;
-
- return r;
-}
-
-// FIXME: the tree should not be touched if insert fails (eg, OOM)
-static bool _insert(struct radix_tree *rt, struct value *v, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- if (kb == ke) {
- if (v->type == UNSET) {
- v->type = VALUE;
- v->value = rv;
- rt->nr_entries++;
-
- } else if (v->type == VALUE) {
- v->value = rv;
-
- } else {
- struct value_chain *vc = zalloc(sizeof(*vc));
- if (!vc)
- return false;
-
- vc->value = rv;
- vc->child = *v;
- v->type = VALUE_CHAIN;
- v->value.ptr = vc;
- rt->nr_entries++;
- }
- return true;
- }
-
- switch (v->type) {
- case UNSET:
- return _insert_unset(rt, v, kb, ke, rv);
-
- case VALUE:
- return _insert_value(rt, v, kb, ke, rv);
-
- case VALUE_CHAIN:
- return _insert_value_chain(rt, v, kb, ke, rv);
-
- case PREFIX_CHAIN:
- return _insert_prefix_chain(rt, v, kb, ke, rv);
-
- case NODE4:
- return _insert_node4(rt, v, kb, ke, rv);
-
- case NODE16:
- return _insert_node16(rt, v, kb, ke, rv);
-
- case NODE48:
- return _insert_node48(rt, v, kb, ke, rv);
-
- case NODE256:
- return _insert_node256(rt, v, kb, ke, rv);
- }
-
- // can't get here
- return false;
-}
-
-struct lookup_result {
- struct value *v;
- uint8_t *kb;
-};
-
-static struct lookup_result _lookup_prefix(struct value *v, uint8_t *kb, uint8_t *ke)
-{
- unsigned i;
- struct value_chain *vc;
- struct prefix_chain *pc;
- struct node4 *n4;
- struct node16 *n16;
- struct node48 *n48;
- struct node256 *n256;
-
- if (kb == ke)
- return (struct lookup_result) {.v = v, .kb = kb};
-
- switch (v->type) {
- case UNSET:
- case VALUE:
- break;
-
- case VALUE_CHAIN:
- vc = v->value.ptr;
- return _lookup_prefix(&vc->child, kb, ke);
-
- case PREFIX_CHAIN:
- pc = v->value.ptr;
- if (ke - kb < pc->len)
- return (struct lookup_result) {.v = v, .kb = kb};
-
- for (i = 0; i < pc->len; i++)
- if (kb[i] != pc->prefix[i])
- return (struct lookup_result) {.v = v, .kb = kb};
-
- return _lookup_prefix(&pc->child, kb + pc->len, ke);
-
- case NODE4:
- n4 = v->value.ptr;
- for (i = 0; i < n4->nr_entries; i++)
- if (n4->keys[i] == *kb)
- return _lookup_prefix(n4->values + i, kb + 1, ke);
- break;
-
- case NODE16:
- // FIXME: use binary search or simd?
- n16 = v->value.ptr;
- for (i = 0; i < n16->nr_entries; i++)
- if (n16->keys[i] == *kb)
- return _lookup_prefix(n16->values + i, kb + 1, ke);
- break;
-
- case NODE48:
- n48 = v->value.ptr;
- i = n48->keys[*kb];
- if (i < 48)
- return _lookup_prefix(n48->values + i, kb + 1, ke);
- break;
-
- case NODE256:
- n256 = v->value.ptr;
- if (n256->values[*kb].type != UNSET)
- return _lookup_prefix(n256->values + *kb, kb + 1, ke);
- break;
- }
-
- return (struct lookup_result) {.v = v, .kb = kb};
-}
-
-bool radix_tree_insert(struct radix_tree *rt, uint8_t *kb, uint8_t *ke, union radix_value rv)
-{
- struct lookup_result lr = _lookup_prefix(&rt->root, kb, ke);
- return _insert(rt, lr.v, lr.kb, ke, rv);
-}
-
-// Note the degrade functions also free the original node.
-static void _degrade_to_n4(struct node16 *n16, struct value *result)
-{
- struct node4 *n4 = zalloc(sizeof(*n4));
-
- n4->nr_entries = n16->nr_entries;
- memcpy(n4->keys, n16->keys, n16->nr_entries * sizeof(*n4->keys));
- memcpy(n4->values, n16->values, n16->nr_entries * sizeof(*n4->values));
- free(n16);
-
- result->type = NODE4;
- result->value.ptr = n4;
-}
-
-static void _degrade_to_n16(struct node48 *n48, struct value *result)
-{
- unsigned i, count = 0;
- struct node16 *n16 = zalloc(sizeof(*n16));
-
- n16->nr_entries = n48->nr_entries;
- for (i = 0; i < 256; i++) {
- if (n48->keys[i] < 48) {
- n16->keys[count] = i;
- count++;
- }
- }
-
- memcpy(n16->values, n48->values, n48->nr_entries * sizeof(*n16->values));
-
- free(n48);
-
- result->type = NODE16;
- result->value.ptr = n16;
-}
-
-static void _degrade_to_n48(struct node256 *n256, struct value *result)
-{
- unsigned i, count = 0;
- struct node48 *n48 = zalloc(sizeof(*n48));
-
- memset(n48->keys, 48, sizeof(n48->keys));
-
- n48->nr_entries = n256->nr_entries;
- for (i = 0; i < 256; i++) {
- if (n256->values[i].type == UNSET)
- continue;
-
- n48->keys[i] = count;
- n48->values[count] = n256->values[i];
- count++;
- }
-
- free(n256);
-
- result->type = NODE48;
- result->value.ptr = n48;
-}
-
-// Removes an entry in an array by sliding the values above it down.
-static void _erase_elt(void *array, unsigned obj_size, unsigned count, unsigned index)
-{
- if (index == (count - 1))
- // The simple case
- return;
-
- memmove(((uint8_t *) array) + (obj_size * index),
- ((uint8_t *) array) + (obj_size * (index + 1)),
- obj_size * (count - index - 1));
-
- // Zero the now unused last elt (set's v.type to UNSET)
- memset(((uint8_t *) array) + (count - 1) * obj_size, 0, obj_size);
-}
-
-static bool _remove(struct radix_tree *rt, struct value *root, uint8_t *kb, uint8_t *ke)
-{
- bool r;
- unsigned i, j;
- struct value_chain *vc;
- struct prefix_chain *pc;
- struct node4 *n4;
- struct node16 *n16;
- struct node48 *n48;
- struct node256 *n256;
-
- if (kb == ke) {
- if (root->type == VALUE) {
- root->type = UNSET;
- _dtr(rt, root->value);
- return true;
-
- } else if (root->type == VALUE_CHAIN) {
- vc = root->value.ptr;
- _dtr(rt, vc->value);
- memcpy(root, &vc->child, sizeof(*root));
- free(vc);
- return true;
-
- } else
- return false;
- }
-
- switch (root->type) {
- case UNSET:
- case VALUE:
- // this is a value for a prefix of the key
- return false;
-
- case VALUE_CHAIN:
- vc = root->value.ptr;
- r = _remove(rt, &vc->child, kb, ke);
- if (r && (vc->child.type == UNSET)) {
- root->type = VALUE;
- root->value = vc->value;
- free(vc);
- }
- return r;
-
- case PREFIX_CHAIN:
- pc = root->value.ptr;
- if (ke - kb < pc->len)
- return false;
-
- for (i = 0; i < pc->len; i++)
- if (kb[i] != pc->prefix[i])
- return false;
-
- r = _remove(rt, &pc->child, kb + pc->len, ke);
- if (r && pc->child.type == UNSET) {
- root->type = UNSET;
- free(pc);
- }
- return r;
-
- case NODE4:
- n4 = root->value.ptr;
- for (i = 0; i < n4->nr_entries; i++) {
- if (n4->keys[i] == *kb) {
- r = _remove(rt, n4->values + i, kb + 1, ke);
- if (r && n4->values[i].type == UNSET) {
- if (i < n4->nr_entries) {
- _erase_elt(n4->keys, sizeof(*n4->keys), n4->nr_entries, i);
- _erase_elt(n4->values, sizeof(*n4->values), n4->nr_entries, i);
- }
-
- n4->nr_entries--;
- if (!n4->nr_entries) {
- free(n4);
- root->type = UNSET;
- }
- }
- return r;
- }
- }
- return false;
-
- case NODE16:
- n16 = root->value.ptr;
- for (i = 0; i < n16->nr_entries; i++) {
- if (n16->keys[i] == *kb) {
- r = _remove(rt, n16->values + i, kb + 1, ke);
- if (r && n16->values[i].type == UNSET) {
- if (i < n16->nr_entries) {
- _erase_elt(n16->keys, sizeof(*n16->keys), n16->nr_entries, i);
- _erase_elt(n16->values, sizeof(*n16->values), n16->nr_entries, i);
- }
-
- n16->nr_entries--;
- if (n16->nr_entries <= 4) {
- _degrade_to_n4(n16, root);
- }
- }
- return r;
- }
- }
- return false;
-
- case NODE48:
- n48 = root->value.ptr;
- i = n48->keys[*kb];
- if (i < 48) {
- r = _remove(rt, n48->values + i, kb + 1, ke);
- if (r && n48->values[i].type == UNSET) {
- n48->keys[*kb] = 48;
- for (j = 0; j < 256; j++)
- if (n48->keys[j] < 48 && n48->keys[j] > i)
- n48->keys[j]--;
- _erase_elt(n48->values, sizeof(*n48->values), n48->nr_entries, i);
- n48->nr_entries--;
- if (n48->nr_entries <= 16)
- _degrade_to_n16(n48, root);
- }
- return r;
- }
- return false;
-
- case NODE256:
- n256 = root->value.ptr;
- r = _remove(rt, n256->values + (*kb), kb + 1, ke);
- if (r && n256->values[*kb].type == UNSET) {
- n256->nr_entries--;
- if (n256->nr_entries <= 48)
- _degrade_to_n48(n256, root);
- }
- return r;
- }
-
- return false;
-}
-
-bool radix_tree_remove(struct radix_tree *rt, uint8_t *key_begin, uint8_t *key_end)
-{
- if (_remove(rt, &rt->root, key_begin, key_end)) {
- rt->nr_entries--;
- return true;
- }
-
- return false;
-}
-
-//----------------------------------------------------------------
-
-static bool _prefix_chain_matches(struct lookup_result *lr, uint8_t *ke)
-{
- // It's possible the top node is a prefix chain, and
- // the remaining key matches part of it.
- if (lr->v->type == PREFIX_CHAIN) {
- unsigned i, rlen = ke - lr->kb;
- struct prefix_chain *pc = lr->v->value.ptr;
- if (rlen < pc->len) {
- for (i = 0; i < rlen; i++)
- if (pc->prefix[i] != lr->kb[i])
- return false;
- return true;
- }
- }
-
- return false;
-}
-
-static bool _remove_subtree(struct radix_tree *rt, struct value *root, uint8_t *kb, uint8_t *ke, unsigned *count)
-{
- bool r;
- unsigned i, j, len;
- struct value_chain *vc;
- struct prefix_chain *pc;
- struct node4 *n4;
- struct node16 *n16;
- struct node48 *n48;
- struct node256 *n256;
-
- if (kb == ke) {
- *count += _free_node(rt, *root);
- root->type = UNSET;
- return true;
- }
-
- switch (root->type) {
- case UNSET:
- case VALUE:
- // No entries with the given prefix
- return true;
-
- case VALUE_CHAIN:
- vc = root->value.ptr;
- r = _remove_subtree(rt, &vc->child, kb, ke, count);
- if (r && (vc->child.type == UNSET)) {
- root->type = VALUE;
- root->value = vc->value;
- free(vc);
- }
- return r;
-
- case PREFIX_CHAIN:
- pc = root->value.ptr;
- len = min(pc->len, ke - kb);
- for (i = 0; i < len; i++)
- if (kb[i] != pc->prefix[i])
- return true;
-
- r = _remove_subtree(rt, &pc->child, len < pc->len ? ke : (kb + pc->len), ke, count);
- if (r && pc->child.type == UNSET) {
- root->type = UNSET;
- free(pc);
- }
- return r;
-
- case NODE4:
- n4 = root->value.ptr;
- for (i = 0; i < n4->nr_entries; i++) {
- if (n4->keys[i] == *kb) {
- r = _remove_subtree(rt, n4->values + i, kb + 1, ke, count);
- if (r && n4->values[i].type == UNSET) {
- if (i < n4->nr_entries) {
- _erase_elt(n4->keys, sizeof(*n4->keys), n4->nr_entries, i);
- _erase_elt(n4->values, sizeof(*n4->values), n4->nr_entries, i);
- }
-
- n4->nr_entries--;
- if (!n4->nr_entries) {
- free(n4);
- root->type = UNSET;
- }
- }
- return r;
- }
- }
- return true;
-
- case NODE16:
- n16 = root->value.ptr;
- for (i = 0; i < n16->nr_entries; i++) {
- if (n16->keys[i] == *kb) {
- r = _remove_subtree(rt, n16->values + i, kb + 1, ke, count);
- if (r && n16->values[i].type == UNSET) {
- if (i < n16->nr_entries) {
- _erase_elt(n16->keys, sizeof(*n16->keys), n16->nr_entries, i);
- _erase_elt(n16->values, sizeof(*n16->values), n16->nr_entries, i);
- }
-
- n16->nr_entries--;
- if (n16->nr_entries <= 4)
- _degrade_to_n4(n16, root);
- }
- return r;
- }
- }
- return true;
-
- case NODE48:
- n48 = root->value.ptr;
- i = n48->keys[*kb];
- if (i < 48) {
- r = _remove_subtree(rt, n48->values + i, kb + 1, ke, count);
- if (r && n48->values[i].type == UNSET) {
- n48->keys[*kb] = 48;
- for (j = 0; j < 256; j++)
- if (n48->keys[j] < 48 && n48->keys[j] > i)
- n48->keys[j]--;
- _erase_elt(n48->values, sizeof(*n48->values), n48->nr_entries, i);
- n48->nr_entries--;
- if (n48->nr_entries <= 16)
- _degrade_to_n16(n48, root);
- }
- return r;
- }
- return true;
-
- case NODE256:
- n256 = root->value.ptr;
- if (n256->values[*kb].type == UNSET)
- return true; // No entries
-
- r = _remove_subtree(rt, n256->values + (*kb), kb + 1, ke, count);
- if (r && n256->values[*kb].type == UNSET) {
- n256->nr_entries--;
- if (n256->nr_entries <= 48)
- _degrade_to_n48(n256, root);
- }
- return r;
- }
-
- // Shouldn't get here
- return false;
-}
-
-unsigned radix_tree_remove_prefix(struct radix_tree *rt, uint8_t *kb, uint8_t *ke)
-{
- unsigned count = 0;
-
- if (_remove_subtree(rt, &rt->root, kb, ke, &count))
- rt->nr_entries -= count;
-
- return count;
-}
-
-//----------------------------------------------------------------
-
-bool radix_tree_lookup(struct radix_tree *rt,
- uint8_t *kb, uint8_t *ke, union radix_value *result)
-{
- struct value_chain *vc;
- struct lookup_result lr = _lookup_prefix(&rt->root, kb, ke);
- if (lr.kb == ke) {
- switch (lr.v->type) {
- case VALUE:
- *result = lr.v->value;
- return true;
-
- case VALUE_CHAIN:
- vc = lr.v->value.ptr;
- *result = vc->value;
- return true;
-
- default:
- return false;
- }
- }
-
- return false;
-}
-
-// FIXME: build up the keys too
-static bool _iterate(struct value *v, struct radix_tree_iterator *it)
-{
- unsigned i;
- struct value_chain *vc;
- struct prefix_chain *pc;
- struct node4 *n4;
- struct node16 *n16;
- struct node48 *n48;
- struct node256 *n256;
-
- switch (v->type) {
- case UNSET:
- // can't happen
- break;
-
- case VALUE:
- return it->visit(it, NULL, NULL, v->value);
-
- case VALUE_CHAIN:
- vc = v->value.ptr;
- return it->visit(it, NULL, NULL, vc->value) && _iterate(&vc->child, it);
-
- case PREFIX_CHAIN:
- pc = v->value.ptr;
- return _iterate(&pc->child, it);
-
- case NODE4:
- n4 = (struct node4 *) v->value.ptr;
- for (i = 0; i < n4->nr_entries; i++)
- if (!_iterate(n4->values + i, it))
- return false;
- return true;
-
- case NODE16:
- n16 = (struct node16 *) v->value.ptr;
- for (i = 0; i < n16->nr_entries; i++)
- if (!_iterate(n16->values + i, it))
- return false;
- return true;
-
- case NODE48:
- n48 = (struct node48 *) v->value.ptr;
- for (i = 0; i < n48->nr_entries; i++)
- if (!_iterate(n48->values + i, it))
- return false;
- return true;
-
- case NODE256:
- n256 = (struct node256 *) v->value.ptr;
- for (i = 0; i < 256; i++)
- if (n256->values[i].type != UNSET && !_iterate(n256->values + i, it))
- return false;
- return true;
- }
-
- // can't get here
- return false;
-}
-
-void radix_tree_iterate(struct radix_tree *rt, uint8_t *kb, uint8_t *ke,
- struct radix_tree_iterator *it)
-{
- struct lookup_result lr = _lookup_prefix(&rt->root, kb, ke);
- if (lr.kb == ke || _prefix_chain_matches(&lr, ke))
- _iterate(lr.v, it);
-}
-
-//----------------------------------------------------------------
-// Checks:
-// 1) The number of entries matches rt->nr_entries
-// 2) The number of entries is correct in each node
-// 3) prefix chain len > 0
-// 4) all unused values are UNSET
-
-static bool _check_nodes(struct value *v, unsigned *count)
-{
- unsigned i, ncount;
- struct value_chain *vc;
- struct prefix_chain *pc;
- struct node4 *n4;
- struct node16 *n16;
- struct node48 *n48;
- struct node256 *n256;
-
- switch (v->type) {
- case UNSET:
- return true;
-
- case VALUE:
- (*count)++;
- return true;
-
- case VALUE_CHAIN:
- (*count)++;
- vc = v->value.ptr;
- return _check_nodes(&vc->child, count);
-
- case PREFIX_CHAIN:
- pc = v->value.ptr;
- return _check_nodes(&pc->child, count);
-
- case NODE4:
- n4 = v->value.ptr;
- for (i = 0; i < n4->nr_entries; i++)
- if (!_check_nodes(n4->values + i, count))
- return false;
-
- for (i = n4->nr_entries; i < 4; i++)
- if (n4->values[i].type != UNSET) {
- fprintf(stderr, "unused value is not UNSET (n4)\n");
- return false;
- }
-
- return true;
-
- case NODE16:
- n16 = v->value.ptr;
- for (i = 0; i < n16->nr_entries; i++)
- if (!_check_nodes(n16->values + i, count))
- return false;
-
- for (i = n16->nr_entries; i < 16; i++)
- if (n16->values[i].type != UNSET) {
- fprintf(stderr, "unused value is not UNSET (n16)\n");
- return false;
- }
-
- return true;
-
- case NODE48:
- n48 = v->value.ptr;
- ncount = 0;
- for (i = 0; i < 256; i++) {
- if (n48->keys[i] < 48) {
- ncount++;
- if (!_check_nodes(n48->values + n48->keys[i], count))
- return false;
- }
- }
-
- if (ncount != n48->nr_entries) {
- fprintf(stderr, "incorrect number of entries in n48, n48->nr_entries = %u, actual = %u\n",
- n48->nr_entries, ncount);
- return false;
- }
-
- for (i = n48->nr_entries; i < 48; i++)
- if (n48->values[i].type != UNSET) {
- fprintf(stderr, "unused value is not UNSET (n48)\n");
- return false;
- }
-
- return true;
-
- case NODE256:
- n256 = v->value.ptr;
-
- ncount = 0;
- for (i = 0; i < 256; i++) {
- struct value *v2 = n256->values + i;
-
- if (v2->type == UNSET)
- continue;
-
- if (!_check_nodes(v2, count))
- return false;
-
- ncount++;
- }
-
- if (ncount != n256->nr_entries) {
- fprintf(stderr, "incorrect number of entries in n256, n256->nr_entries = %u, actual = %u\n",
- n256->nr_entries, ncount);
- return false;
- }
-
- return true;
-
- default:
- fprintf(stderr, "unknown value type: %u\n", v->type);
- }
-
- fprintf(stderr, "shouldn't get here\n");
- return false;
-}
-
-bool radix_tree_is_well_formed(struct radix_tree *rt)
-{
- unsigned count = 0;
-
- if (!_check_nodes(&rt->root, &count))
- return false;
-
- if (rt->nr_entries != count) {
- fprintf(stderr, "incorrect entry count: rt->nr_entries = %u, actual = %u\n",
- rt->nr_entries, count);
- return false;
- }
-
- return true;
-}
-
-//----------------------------------------------------------------
-
-static void _dump(FILE *out, struct value v, unsigned indent)
-{
- unsigned i;
- struct value_chain *vc;
- struct prefix_chain *pc;
- struct node4 *n4;
- struct node16 *n16;
- struct node48 *n48;
- struct node256 *n256;
-
- if (v.type == UNSET)
- return;
-
- for (i = 0; i < 2 * indent; i++)
- fprintf(out, " ");
-
- switch (v.type) {
- case UNSET:
- // can't happen
- break;
-
- case VALUE:
- fprintf(out, "<val: %llu>\n", (unsigned long long) v.value.n);
- break;
-
- case VALUE_CHAIN:
- vc = v.value.ptr;
- fprintf(out, "<val_chain: %llu>\n", (unsigned long long) vc->value.n);
- _dump(out, vc->child, indent + 1);
- break;
-
- case PREFIX_CHAIN:
- pc = v.value.ptr;
- fprintf(out, "<prefix: ");
- for (i = 0; i < pc->len; i++)
- fprintf(out, "%x.", (unsigned) *(pc->prefix + i));
- fprintf(out, ">\n");
- _dump(out, pc->child, indent + 1);
- break;
-
- case NODE4:
- n4 = v.value.ptr;
- fprintf(out, "<n4: ");
- for (i = 0; i < n4->nr_entries; i++)
- fprintf(out, "%x ", (unsigned) n4->keys[i]);
- fprintf(out, ">\n");
-
- for (i = 0; i < n4->nr_entries; i++)
- _dump(out, n4->values[i], indent + 1);
- break;
-
- case NODE16:
- n16 = v.value.ptr;
- fprintf(out, "<n16: ");
- for (i = 0; i < n16->nr_entries; i++)
- fprintf(out, "%x ", (unsigned) n16->keys[i]);
- fprintf(out, ">\n");
-
- for (i = 0; i < n16->nr_entries; i++)
- _dump(out, n16->values[i], indent + 1);
- break;
-
- case NODE48:
- n48 = v.value.ptr;
- fprintf(out, "<n48: ");
- for (i = 0; i < 256; i++)
- if (n48->keys[i] < 48)
- fprintf(out, "%x ", i);
- fprintf(out, ">\n");
-
- for (i = 0; i < 256; i++)
- if (n48->keys[i] < 48)
- _dump(out, n48->values[i], indent + 1);
- break;
-
- case NODE256:
- n256 = v.value.ptr;
- fprintf(out, "<n256: ");
- for (i = 0; i < 256; i++)
- if (n256->values[i].type != UNSET)
- fprintf(out, "%x ", i);
- fprintf(out, ">\n");
-
- for (i = 0; i < 256; i++)
- if (n256->values[i].type != UNSET)
- _dump(out, n256->values[i], indent + 1);
- break;
- }
-}
-
-void radix_tree_dump(struct radix_tree *rt, FILE *out)
-{
- _dump(out, rt->root, 0);
-}
+#ifdef SIMPLE_RADIX_TREE
+#include "base/data-struct/radix-tree-simple.c"
+#else
+#include "base/data-struct/radix-tree-adaptive.c"
+#endif
//----------------------------------------------------------------
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