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Diffstat (limited to 'src/contrib/libngtcp2/ngtcp2/lib/ngtcp2_ksl.c')
-rw-r--r--src/contrib/libngtcp2/ngtcp2/lib/ngtcp2_ksl.c819
1 files changed, 819 insertions, 0 deletions
diff --git a/src/contrib/libngtcp2/ngtcp2/lib/ngtcp2_ksl.c b/src/contrib/libngtcp2/ngtcp2/lib/ngtcp2_ksl.c
new file mode 100644
index 0000000..0bd424c
--- /dev/null
+++ b/src/contrib/libngtcp2/ngtcp2/lib/ngtcp2_ksl.c
@@ -0,0 +1,819 @@
+/*
+ * ngtcp2
+ *
+ * Copyright (c) 2018 ngtcp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "ngtcp2_ksl.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <stdio.h>
+
+#include "ngtcp2_macro.h"
+#include "ngtcp2_mem.h"
+#include "ngtcp2_range.h"
+
+static ngtcp2_ksl_blk null_blk = {{{NULL, NULL, 0, 0, {0}}}};
+
+static size_t ksl_nodelen(size_t keylen) {
+ return (sizeof(ngtcp2_ksl_node) + keylen - sizeof(uint64_t) + 0xfu) &
+ ~(uintptr_t)0xfu;
+}
+
+static size_t ksl_blklen(size_t nodelen) {
+ return sizeof(ngtcp2_ksl_blk) + nodelen * NGTCP2_KSL_MAX_NBLK -
+ sizeof(uint64_t);
+}
+
+/*
+ * ksl_node_set_key sets |key| to |node|.
+ */
+static void ksl_node_set_key(ngtcp2_ksl *ksl, ngtcp2_ksl_node *node,
+ const void *key) {
+ memcpy(node->key, key, ksl->keylen);
+}
+
+void ngtcp2_ksl_init(ngtcp2_ksl *ksl, ngtcp2_ksl_compar compar, size_t keylen,
+ const ngtcp2_mem *mem) {
+ size_t nodelen = ksl_nodelen(keylen);
+
+ ngtcp2_objalloc_init(&ksl->blkalloc,
+ ((ksl_blklen(nodelen) + 0xfu) & ~(uintptr_t)0xfu) * 8,
+ mem);
+
+ ksl->head = NULL;
+ ksl->front = ksl->back = NULL;
+ ksl->compar = compar;
+ ksl->keylen = keylen;
+ ksl->nodelen = nodelen;
+ ksl->n = 0;
+}
+
+static ngtcp2_ksl_blk *ksl_blk_objalloc_new(ngtcp2_ksl *ksl) {
+ return ngtcp2_objalloc_ksl_blk_len_get(&ksl->blkalloc,
+ ksl_blklen(ksl->nodelen));
+}
+
+static void ksl_blk_objalloc_del(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk) {
+ ngtcp2_objalloc_ksl_blk_release(&ksl->blkalloc, blk);
+}
+
+static int ksl_head_init(ngtcp2_ksl *ksl) {
+ ngtcp2_ksl_blk *head = ksl_blk_objalloc_new(ksl);
+ if (!head) {
+ return NGTCP2_ERR_NOMEM;
+ }
+
+ head->next = head->prev = NULL;
+ head->n = 0;
+ head->leaf = 1;
+
+ ksl->head = head;
+ ksl->front = ksl->back = head;
+
+ return 0;
+}
+
+#ifdef NOMEMPOOL
+/*
+ * ksl_free_blk frees |blk| recursively.
+ */
+static void ksl_free_blk(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk) {
+ size_t i;
+
+ if (!blk->leaf) {
+ for (i = 0; i < blk->n; ++i) {
+ ksl_free_blk(ksl, ngtcp2_ksl_nth_node(ksl, blk, i)->blk);
+ }
+ }
+
+ ksl_blk_objalloc_del(ksl, blk);
+}
+#endif /* NOMEMPOOL */
+
+void ngtcp2_ksl_free(ngtcp2_ksl *ksl) {
+ if (!ksl || !ksl->head) {
+ return;
+ }
+
+#ifdef NOMEMPOOL
+ ksl_free_blk(ksl, ksl->head);
+#endif /* NOMEMPOOL */
+
+ ngtcp2_objalloc_free(&ksl->blkalloc);
+}
+
+/*
+ * ksl_split_blk splits |blk| into 2 ngtcp2_ksl_blk objects. The new
+ * ngtcp2_ksl_blk is always the "right" block.
+ *
+ * It returns the pointer to the ngtcp2_ksl_blk created which is the
+ * located at the right of |blk|, or NULL which indicates out of
+ * memory error.
+ */
+static ngtcp2_ksl_blk *ksl_split_blk(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk) {
+ ngtcp2_ksl_blk *rblk;
+
+ rblk = ksl_blk_objalloc_new(ksl);
+ if (rblk == NULL) {
+ return NULL;
+ }
+
+ rblk->next = blk->next;
+ blk->next = rblk;
+ if (rblk->next) {
+ rblk->next->prev = rblk;
+ } else if (ksl->back == blk) {
+ ksl->back = rblk;
+ }
+ rblk->prev = blk;
+ rblk->leaf = blk->leaf;
+
+ rblk->n = blk->n / 2;
+
+ memcpy(rblk->nodes, blk->nodes + ksl->nodelen * (blk->n - rblk->n),
+ ksl->nodelen * rblk->n);
+
+ blk->n -= rblk->n;
+
+ assert(blk->n >= NGTCP2_KSL_MIN_NBLK);
+ assert(rblk->n >= NGTCP2_KSL_MIN_NBLK);
+
+ return rblk;
+}
+
+/*
+ * ksl_split_node splits a node included in |blk| at the position |i|
+ * into 2 adjacent nodes. The new node is always inserted at the
+ * position |i+1|.
+ *
+ * It returns 0 if it succeeds, or one of the following negative error
+ * codes:
+ *
+ * NGTCP2_ERR_NOMEM
+ * Out of memory.
+ */
+static int ksl_split_node(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk, size_t i) {
+ ngtcp2_ksl_node *node;
+ ngtcp2_ksl_blk *lblk = ngtcp2_ksl_nth_node(ksl, blk, i)->blk, *rblk;
+
+ rblk = ksl_split_blk(ksl, lblk);
+ if (rblk == NULL) {
+ return NGTCP2_ERR_NOMEM;
+ }
+
+ memmove(blk->nodes + (i + 2) * ksl->nodelen,
+ blk->nodes + (i + 1) * ksl->nodelen,
+ ksl->nodelen * (blk->n - (i + 1)));
+
+ node = ngtcp2_ksl_nth_node(ksl, blk, i + 1);
+ node->blk = rblk;
+ ++blk->n;
+ ksl_node_set_key(ksl, node, ngtcp2_ksl_nth_node(ksl, rblk, rblk->n - 1)->key);
+
+ node = ngtcp2_ksl_nth_node(ksl, blk, i);
+ ksl_node_set_key(ksl, node, ngtcp2_ksl_nth_node(ksl, lblk, lblk->n - 1)->key);
+
+ return 0;
+}
+
+/*
+ * ksl_split_head splits a head (root) block. It increases the height
+ * of skip list by 1.
+ *
+ * It returns 0 if it succeeds, or one of the following negative error
+ * codes:
+ *
+ * NGTCP2_ERR_NOMEM
+ * Out of memory.
+ */
+static int ksl_split_head(ngtcp2_ksl *ksl) {
+ ngtcp2_ksl_blk *rblk = NULL, *lblk, *nhead = NULL;
+ ngtcp2_ksl_node *node;
+
+ rblk = ksl_split_blk(ksl, ksl->head);
+ if (rblk == NULL) {
+ return NGTCP2_ERR_NOMEM;
+ }
+
+ lblk = ksl->head;
+
+ nhead = ksl_blk_objalloc_new(ksl);
+ if (nhead == NULL) {
+ ksl_blk_objalloc_del(ksl, rblk);
+ return NGTCP2_ERR_NOMEM;
+ }
+ nhead->next = nhead->prev = NULL;
+ nhead->n = 2;
+ nhead->leaf = 0;
+
+ node = ngtcp2_ksl_nth_node(ksl, nhead, 0);
+ ksl_node_set_key(ksl, node, ngtcp2_ksl_nth_node(ksl, lblk, lblk->n - 1)->key);
+ node->blk = lblk;
+
+ node = ngtcp2_ksl_nth_node(ksl, nhead, 1);
+ ksl_node_set_key(ksl, node, ngtcp2_ksl_nth_node(ksl, rblk, rblk->n - 1)->key);
+ node->blk = rblk;
+
+ ksl->head = nhead;
+
+ return 0;
+}
+
+/*
+ * insert_node inserts a node whose key is |key| with the associated
+ * |data| at the index of |i|. This function assumes that the number
+ * of nodes contained by |blk| is strictly less than
+ * NGTCP2_KSL_MAX_NBLK.
+ */
+static void ksl_insert_node(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk, size_t i,
+ const ngtcp2_ksl_key *key, void *data) {
+ ngtcp2_ksl_node *node;
+
+ assert(blk->n < NGTCP2_KSL_MAX_NBLK);
+
+ memmove(blk->nodes + (i + 1) * ksl->nodelen, blk->nodes + i * ksl->nodelen,
+ ksl->nodelen * (blk->n - i));
+
+ node = ngtcp2_ksl_nth_node(ksl, blk, i);
+ ksl_node_set_key(ksl, node, key);
+ node->data = data;
+
+ ++blk->n;
+}
+
+static size_t ksl_bsearch(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk,
+ const ngtcp2_ksl_key *key, ngtcp2_ksl_compar compar) {
+ size_t i;
+ ngtcp2_ksl_node *node;
+
+ for (i = 0, node = (ngtcp2_ksl_node *)(void *)blk->nodes;
+ i < blk->n && compar((ngtcp2_ksl_key *)node->key, key);
+ ++i, node = (ngtcp2_ksl_node *)(void *)((uint8_t *)node + ksl->nodelen))
+ ;
+
+ return i;
+}
+
+int ngtcp2_ksl_insert(ngtcp2_ksl *ksl, ngtcp2_ksl_it *it,
+ const ngtcp2_ksl_key *key, void *data) {
+ ngtcp2_ksl_blk *blk;
+ ngtcp2_ksl_node *node;
+ size_t i;
+ int rv;
+
+ if (!ksl->head) {
+ rv = ksl_head_init(ksl);
+ if (rv != 0) {
+ return rv;
+ }
+ }
+
+ blk = ksl->head;
+
+ if (blk->n == NGTCP2_KSL_MAX_NBLK) {
+ rv = ksl_split_head(ksl);
+ if (rv != 0) {
+ return rv;
+ }
+ blk = ksl->head;
+ }
+
+ for (;;) {
+ i = ksl_bsearch(ksl, blk, key, ksl->compar);
+
+ if (blk->leaf) {
+ if (i < blk->n &&
+ !ksl->compar(key, ngtcp2_ksl_nth_node(ksl, blk, i)->key)) {
+ if (it) {
+ *it = ngtcp2_ksl_end(ksl);
+ }
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+ ksl_insert_node(ksl, blk, i, key, data);
+ ++ksl->n;
+ if (it) {
+ ngtcp2_ksl_it_init(it, ksl, blk, i);
+ }
+ return 0;
+ }
+
+ if (i == blk->n) {
+ /* This insertion extends the largest key in this subtree. */
+ for (; !blk->leaf;) {
+ node = ngtcp2_ksl_nth_node(ksl, blk, blk->n - 1);
+ if (node->blk->n == NGTCP2_KSL_MAX_NBLK) {
+ rv = ksl_split_node(ksl, blk, blk->n - 1);
+ if (rv != 0) {
+ return rv;
+ }
+ node = ngtcp2_ksl_nth_node(ksl, blk, blk->n - 1);
+ }
+ ksl_node_set_key(ksl, node, key);
+ blk = node->blk;
+ }
+ ksl_insert_node(ksl, blk, blk->n, key, data);
+ ++ksl->n;
+ if (it) {
+ ngtcp2_ksl_it_init(it, ksl, blk, blk->n - 1);
+ }
+ return 0;
+ }
+
+ node = ngtcp2_ksl_nth_node(ksl, blk, i);
+
+ if (node->blk->n == NGTCP2_KSL_MAX_NBLK) {
+ rv = ksl_split_node(ksl, blk, i);
+ if (rv != 0) {
+ return rv;
+ }
+ if (ksl->compar((ngtcp2_ksl_key *)node->key, key)) {
+ node = ngtcp2_ksl_nth_node(ksl, blk, i + 1);
+ if (ksl->compar((ngtcp2_ksl_key *)node->key, key)) {
+ ksl_node_set_key(ksl, node, key);
+ }
+ }
+ }
+
+ blk = node->blk;
+ }
+}
+
+/*
+ * ksl_remove_node removes the node included in |blk| at the index of
+ * |i|.
+ */
+static void ksl_remove_node(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk, size_t i) {
+ memmove(blk->nodes + i * ksl->nodelen, blk->nodes + (i + 1) * ksl->nodelen,
+ ksl->nodelen * (blk->n - (i + 1)));
+
+ --blk->n;
+}
+
+/*
+ * ksl_merge_node merges 2 nodes which are the nodes at the index of
+ * |i| and |i + 1|.
+ *
+ * If |blk| is the direct descendant of head (root) block and the head
+ * block contains just 2 nodes, the merged block becomes head block,
+ * which decreases the height of |ksl| by 1.
+ *
+ * This function returns the pointer to the merged block.
+ */
+static ngtcp2_ksl_blk *ksl_merge_node(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk,
+ size_t i) {
+ ngtcp2_ksl_blk *lblk, *rblk;
+
+ assert(i + 1 < blk->n);
+
+ lblk = ngtcp2_ksl_nth_node(ksl, blk, i)->blk;
+ rblk = ngtcp2_ksl_nth_node(ksl, blk, i + 1)->blk;
+
+ assert(lblk->n + rblk->n < NGTCP2_KSL_MAX_NBLK);
+
+ memcpy(lblk->nodes + ksl->nodelen * lblk->n, rblk->nodes,
+ ksl->nodelen * rblk->n);
+
+ lblk->n += rblk->n;
+ lblk->next = rblk->next;
+ if (lblk->next) {
+ lblk->next->prev = lblk;
+ } else if (ksl->back == rblk) {
+ ksl->back = lblk;
+ }
+
+ ksl_blk_objalloc_del(ksl, rblk);
+
+ if (ksl->head == blk && blk->n == 2) {
+ ksl_blk_objalloc_del(ksl, ksl->head);
+ ksl->head = lblk;
+ } else {
+ ksl_remove_node(ksl, blk, i + 1);
+ ksl_node_set_key(ksl, ngtcp2_ksl_nth_node(ksl, blk, i),
+ ngtcp2_ksl_nth_node(ksl, lblk, lblk->n - 1)->key);
+ }
+
+ return lblk;
+}
+
+/*
+ * ksl_shift_left moves the first nodes in blk->nodes[i]->blk->nodes
+ * to blk->nodes[i - 1]->blk->nodes in a manner that they have the
+ * same amount of nodes as much as possible.
+ */
+static void ksl_shift_left(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk, size_t i) {
+ ngtcp2_ksl_node *lnode, *rnode;
+ size_t n;
+
+ assert(i > 0);
+
+ lnode = ngtcp2_ksl_nth_node(ksl, blk, i - 1);
+ rnode = ngtcp2_ksl_nth_node(ksl, blk, i);
+
+ assert(lnode->blk->n < NGTCP2_KSL_MAX_NBLK);
+ assert(rnode->blk->n > NGTCP2_KSL_MIN_NBLK);
+
+ n = (lnode->blk->n + rnode->blk->n + 1) / 2 - lnode->blk->n;
+
+ assert(n > 0);
+ assert(lnode->blk->n <= NGTCP2_KSL_MAX_NBLK - n);
+ assert(rnode->blk->n >= NGTCP2_KSL_MIN_NBLK + n);
+
+ memcpy(lnode->blk->nodes + ksl->nodelen * lnode->blk->n, rnode->blk->nodes,
+ ksl->nodelen * n);
+
+ lnode->blk->n += (uint32_t)n;
+ rnode->blk->n -= (uint32_t)n;
+
+ ksl_node_set_key(
+ ksl, lnode, ngtcp2_ksl_nth_node(ksl, lnode->blk, lnode->blk->n - 1)->key);
+
+ memmove(rnode->blk->nodes, rnode->blk->nodes + ksl->nodelen * n,
+ ksl->nodelen * rnode->blk->n);
+}
+
+/*
+ * ksl_shift_right moves the last nodes in blk->nodes[i]->blk->nodes
+ * to blk->nodes[i + 1]->blk->nodes in a manner that they have the
+ * same amount of nodes as much as possible..
+ */
+static void ksl_shift_right(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk, size_t i) {
+ ngtcp2_ksl_node *lnode, *rnode;
+ size_t n;
+
+ assert(i < blk->n - 1);
+
+ lnode = ngtcp2_ksl_nth_node(ksl, blk, i);
+ rnode = ngtcp2_ksl_nth_node(ksl, blk, i + 1);
+
+ assert(lnode->blk->n > NGTCP2_KSL_MIN_NBLK);
+ assert(rnode->blk->n < NGTCP2_KSL_MAX_NBLK);
+
+ n = (lnode->blk->n + rnode->blk->n + 1) / 2 - rnode->blk->n;
+
+ assert(n > 0);
+ assert(lnode->blk->n >= NGTCP2_KSL_MIN_NBLK + n);
+ assert(rnode->blk->n <= NGTCP2_KSL_MAX_NBLK - n);
+
+ memmove(rnode->blk->nodes + ksl->nodelen * n, rnode->blk->nodes,
+ ksl->nodelen * rnode->blk->n);
+
+ rnode->blk->n += (uint32_t)n;
+ lnode->blk->n -= (uint32_t)n;
+
+ memcpy(rnode->blk->nodes, lnode->blk->nodes + ksl->nodelen * lnode->blk->n,
+ ksl->nodelen * n);
+
+ ksl_node_set_key(
+ ksl, lnode, ngtcp2_ksl_nth_node(ksl, lnode->blk, lnode->blk->n - 1)->key);
+}
+
+/*
+ * key_equal returns nonzero if |lhs| and |rhs| are equal using the
+ * function |compar|.
+ */
+static int key_equal(ngtcp2_ksl_compar compar, const ngtcp2_ksl_key *lhs,
+ const ngtcp2_ksl_key *rhs) {
+ return !compar(lhs, rhs) && !compar(rhs, lhs);
+}
+
+int ngtcp2_ksl_remove_hint(ngtcp2_ksl *ksl, ngtcp2_ksl_it *it,
+ const ngtcp2_ksl_it *hint,
+ const ngtcp2_ksl_key *key) {
+ ngtcp2_ksl_blk *blk = hint->blk;
+
+ assert(ksl->head);
+
+ if (blk->n <= NGTCP2_KSL_MIN_NBLK) {
+ return ngtcp2_ksl_remove(ksl, it, key);
+ }
+
+ ksl_remove_node(ksl, blk, hint->i);
+
+ --ksl->n;
+
+ if (it) {
+ if (hint->i == blk->n && blk->next) {
+ ngtcp2_ksl_it_init(it, ksl, blk->next, 0);
+ } else {
+ ngtcp2_ksl_it_init(it, ksl, blk, hint->i);
+ }
+ }
+
+ return 0;
+}
+
+int ngtcp2_ksl_remove(ngtcp2_ksl *ksl, ngtcp2_ksl_it *it,
+ const ngtcp2_ksl_key *key) {
+ ngtcp2_ksl_blk *blk = ksl->head;
+ ngtcp2_ksl_node *node;
+ size_t i;
+
+ if (!ksl->head) {
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ if (!blk->leaf && blk->n == 2 &&
+ ngtcp2_ksl_nth_node(ksl, blk, 0)->blk->n == NGTCP2_KSL_MIN_NBLK &&
+ ngtcp2_ksl_nth_node(ksl, blk, 1)->blk->n == NGTCP2_KSL_MIN_NBLK) {
+ blk = ksl_merge_node(ksl, ksl->head, 0);
+ }
+
+ for (;;) {
+ i = ksl_bsearch(ksl, blk, key, ksl->compar);
+
+ if (i == blk->n) {
+ if (it) {
+ *it = ngtcp2_ksl_end(ksl);
+ }
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+
+ if (blk->leaf) {
+ if (ksl->compar(key, ngtcp2_ksl_nth_node(ksl, blk, i)->key)) {
+ if (it) {
+ *it = ngtcp2_ksl_end(ksl);
+ }
+ return NGTCP2_ERR_INVALID_ARGUMENT;
+ }
+ ksl_remove_node(ksl, blk, i);
+ --ksl->n;
+ if (it) {
+ if (blk->n == i && blk->next) {
+ ngtcp2_ksl_it_init(it, ksl, blk->next, 0);
+ } else {
+ ngtcp2_ksl_it_init(it, ksl, blk, i);
+ }
+ }
+ return 0;
+ }
+
+ node = ngtcp2_ksl_nth_node(ksl, blk, i);
+
+ if (node->blk->n > NGTCP2_KSL_MIN_NBLK) {
+ blk = node->blk;
+ continue;
+ }
+
+ assert(node->blk->n == NGTCP2_KSL_MIN_NBLK);
+
+ if (i + 1 < blk->n &&
+ ngtcp2_ksl_nth_node(ksl, blk, i + 1)->blk->n > NGTCP2_KSL_MIN_NBLK) {
+ ksl_shift_left(ksl, blk, i + 1);
+ blk = node->blk;
+ continue;
+ }
+
+ if (i > 0 &&
+ ngtcp2_ksl_nth_node(ksl, blk, i - 1)->blk->n > NGTCP2_KSL_MIN_NBLK) {
+ ksl_shift_right(ksl, blk, i - 1);
+ blk = node->blk;
+ continue;
+ }
+
+ if (i + 1 < blk->n) {
+ blk = ksl_merge_node(ksl, blk, i);
+ continue;
+ }
+
+ assert(i > 0);
+
+ blk = ksl_merge_node(ksl, blk, i - 1);
+ }
+}
+
+ngtcp2_ksl_it ngtcp2_ksl_lower_bound(ngtcp2_ksl *ksl,
+ const ngtcp2_ksl_key *key) {
+ ngtcp2_ksl_blk *blk = ksl->head;
+ ngtcp2_ksl_it it;
+ size_t i;
+
+ if (!blk) {
+ ngtcp2_ksl_it_init(&it, ksl, &null_blk, 0);
+ return it;
+ }
+
+ for (;;) {
+ i = ksl_bsearch(ksl, blk, key, ksl->compar);
+
+ if (blk->leaf) {
+ if (i == blk->n && blk->next) {
+ blk = blk->next;
+ i = 0;
+ }
+ ngtcp2_ksl_it_init(&it, ksl, blk, i);
+ return it;
+ }
+
+ if (i == blk->n) {
+ /* This happens if descendant has smaller key. Fast forward to
+ find last node in this subtree. */
+ for (; !blk->leaf; blk = ngtcp2_ksl_nth_node(ksl, blk, blk->n - 1)->blk)
+ ;
+ if (blk->next) {
+ blk = blk->next;
+ i = 0;
+ } else {
+ i = blk->n;
+ }
+ ngtcp2_ksl_it_init(&it, ksl, blk, i);
+ return it;
+ }
+ blk = ngtcp2_ksl_nth_node(ksl, blk, i)->blk;
+ }
+}
+
+ngtcp2_ksl_it ngtcp2_ksl_lower_bound_compar(ngtcp2_ksl *ksl,
+ const ngtcp2_ksl_key *key,
+ ngtcp2_ksl_compar compar) {
+ ngtcp2_ksl_blk *blk = ksl->head;
+ ngtcp2_ksl_it it;
+ size_t i;
+
+ if (!blk) {
+ ngtcp2_ksl_it_init(&it, ksl, &null_blk, 0);
+ return it;
+ }
+
+ for (;;) {
+ i = ksl_bsearch(ksl, blk, key, compar);
+
+ if (blk->leaf) {
+ if (i == blk->n && blk->next) {
+ blk = blk->next;
+ i = 0;
+ }
+ ngtcp2_ksl_it_init(&it, ksl, blk, i);
+ return it;
+ }
+
+ if (i == blk->n) {
+ /* This happens if descendant has smaller key. Fast forward to
+ find last node in this subtree. */
+ for (; !blk->leaf; blk = ngtcp2_ksl_nth_node(ksl, blk, blk->n - 1)->blk)
+ ;
+ if (blk->next) {
+ blk = blk->next;
+ i = 0;
+ } else {
+ i = blk->n;
+ }
+ ngtcp2_ksl_it_init(&it, ksl, blk, i);
+ return it;
+ }
+ blk = ngtcp2_ksl_nth_node(ksl, blk, i)->blk;
+ }
+}
+
+void ngtcp2_ksl_update_key(ngtcp2_ksl *ksl, const ngtcp2_ksl_key *old_key,
+ const ngtcp2_ksl_key *new_key) {
+ ngtcp2_ksl_blk *blk = ksl->head;
+ ngtcp2_ksl_node *node;
+ size_t i;
+
+ assert(ksl->head);
+
+ for (;;) {
+ i = ksl_bsearch(ksl, blk, old_key, ksl->compar);
+
+ assert(i < blk->n);
+ node = ngtcp2_ksl_nth_node(ksl, blk, i);
+
+ if (blk->leaf) {
+ assert(key_equal(ksl->compar, (ngtcp2_ksl_key *)node->key, old_key));
+ ksl_node_set_key(ksl, node, new_key);
+ return;
+ }
+
+ if (key_equal(ksl->compar, (ngtcp2_ksl_key *)node->key, old_key) ||
+ ksl->compar((ngtcp2_ksl_key *)node->key, new_key)) {
+ ksl_node_set_key(ksl, node, new_key);
+ }
+
+ blk = node->blk;
+ }
+}
+
+static void ksl_print(ngtcp2_ksl *ksl, ngtcp2_ksl_blk *blk, size_t level) {
+ size_t i;
+ ngtcp2_ksl_node *node;
+
+ fprintf(stderr, "LV=%zu n=%u\n", level, blk->n);
+
+ if (blk->leaf) {
+ for (i = 0; i < blk->n; ++i) {
+ node = ngtcp2_ksl_nth_node(ksl, blk, i);
+ fprintf(stderr, " %" PRId64, *(int64_t *)(void *)node->key);
+ }
+ fprintf(stderr, "\n");
+ return;
+ }
+
+ for (i = 0; i < blk->n; ++i) {
+ ksl_print(ksl, ngtcp2_ksl_nth_node(ksl, blk, i)->blk, level + 1);
+ }
+}
+
+size_t ngtcp2_ksl_len(ngtcp2_ksl *ksl) { return ksl->n; }
+
+void ngtcp2_ksl_clear(ngtcp2_ksl *ksl) {
+ if (!ksl->head) {
+ return;
+ }
+
+#ifdef NOMEMPOOL
+ ksl_free_blk(ksl, ksl->head);
+#endif /* NOMEMPOOL */
+
+ ksl->front = ksl->back = ksl->head = NULL;
+ ksl->n = 0;
+
+ ngtcp2_objalloc_clear(&ksl->blkalloc);
+}
+
+void ngtcp2_ksl_print(ngtcp2_ksl *ksl) {
+ if (!ksl->head) {
+ return;
+ }
+
+ ksl_print(ksl, ksl->head, 0);
+}
+
+ngtcp2_ksl_it ngtcp2_ksl_begin(const ngtcp2_ksl *ksl) {
+ ngtcp2_ksl_it it;
+
+ if (ksl->head) {
+ ngtcp2_ksl_it_init(&it, ksl, ksl->front, 0);
+ } else {
+ ngtcp2_ksl_it_init(&it, ksl, &null_blk, 0);
+ }
+
+ return it;
+}
+
+ngtcp2_ksl_it ngtcp2_ksl_end(const ngtcp2_ksl *ksl) {
+ ngtcp2_ksl_it it;
+
+ if (ksl->head) {
+ ngtcp2_ksl_it_init(&it, ksl, ksl->back, ksl->back->n);
+ } else {
+ ngtcp2_ksl_it_init(&it, ksl, &null_blk, 0);
+ }
+
+ return it;
+}
+
+void ngtcp2_ksl_it_init(ngtcp2_ksl_it *it, const ngtcp2_ksl *ksl,
+ ngtcp2_ksl_blk *blk, size_t i) {
+ it->ksl = ksl;
+ it->blk = blk;
+ it->i = i;
+}
+
+void ngtcp2_ksl_it_prev(ngtcp2_ksl_it *it) {
+ assert(!ngtcp2_ksl_it_begin(it));
+
+ if (it->i == 0) {
+ it->blk = it->blk->prev;
+ it->i = it->blk->n - 1;
+ } else {
+ --it->i;
+ }
+}
+
+int ngtcp2_ksl_it_begin(const ngtcp2_ksl_it *it) {
+ return it->i == 0 && it->blk->prev == NULL;
+}
+
+int ngtcp2_ksl_range_compar(const ngtcp2_ksl_key *lhs,
+ const ngtcp2_ksl_key *rhs) {
+ const ngtcp2_range *a = lhs, *b = rhs;
+ return a->begin < b->begin;
+}
+
+int ngtcp2_ksl_range_exclusive_compar(const ngtcp2_ksl_key *lhs,
+ const ngtcp2_ksl_key *rhs) {
+ const ngtcp2_range *a = lhs, *b = rhs;
+ return a->begin < b->begin &&
+ !(ngtcp2_max(a->begin, b->begin) < ngtcp2_min(a->end, b->end));
+}