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-rw-r--r--zix/trie.c353
1 files changed, 0 insertions, 353 deletions
diff --git a/zix/trie.c b/zix/trie.c
deleted file mode 100644
index 1a2d3f6..0000000
--- a/zix/trie.c
+++ /dev/null
@@ -1,353 +0,0 @@
-/*
- Copyright 2011-2016 David Robillard <http://drobilla.net>
-
- Permission to use, copy, modify, and/or distribute this software for any
- purpose with or without fee is hereby granted, provided that the above
- copyright notice and this permission notice appear in all copies.
-
- THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-
-#define _XOPEN_SOURCE 500
-
-#include "zix/trie.h"
-
-#include "zix/common.h"
-#include "zix/trie_util.h"
-
-#include <assert.h>
-#include <stdbool.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-// #define ZIX_TRIE_LINEAR_SEARCH 1
-
-//typedef uint_fast8_t n_edges_t;
-typedef uintptr_t n_edges_t;
-
-typedef struct {
- const uint8_t* str; /* String stored at this node */
- n_edges_t num_children; /* Number of outgoing edges */
-
- /** Array of first child characters, followed by parallel array of pointers
- to ZixTrieNode pointers. */
- uint8_t children[];
-} ZixTrieNode;
-
-struct _ZixTrie {
- ZixTrieNode* root; /* Root of the tree */
-};
-
-/** Round `size` up to the next multiple of the word size. */
-ZIX_PRIVATE n_edges_t
-zix_trie_pad(n_edges_t size)
-{
- return (size + sizeof(void*) - 1) & (~(sizeof(void*) - 1));
-}
-
-ZIX_PRIVATE ZixTrieNode**
-zix_trie_get_children(ZixTrieNode* node)
-{
- return (ZixTrieNode**)(node->children +
- zix_trie_pad(node->num_children));
-}
-
-ZIX_PRIVATE ZixTrieNode**
-zix_trie_get_child_ptr(ZixTrieNode* node, n_edges_t index)
-{
- return zix_trie_get_children(node) + index;
-}
-
-ZIX_PRIVATE void
-zix_trie_print_rec(ZixTrieNode* node, FILE* fd)
-{
- if (node->str) {
- fprintf(fd, "\t\"%p\" [label=\"%s\"] ;\n", (void*)node, node->str);
- } else {
- fprintf(fd, "\t\"%p\" [label=\"\"] ;\n", (void*)node);
- }
-
- for (n_edges_t i = 0; i < node->num_children; ++i) {
- ZixTrieNode* const child = *zix_trie_get_child_ptr(node, i);
- zix_trie_print_rec(child, fd);
- fprintf(fd, "\t\"%p\" -> \"%p\" [ label = \"%c\" ];\n",
- (void*)node, (void*)child, node->children[i]);
- }
-}
-
-void
-zix_trie_print_dot(const ZixTrie* t, FILE* fd)
-{
- fprintf(fd, "digraph Trie { \n");
- zix_trie_print_rec(t->root, fd);
- fprintf(fd, "}\n");
-}
-
-ZIX_PRIVATE size_t
-zix_trie_node_size(n_edges_t num_children)
-{
- return (sizeof(ZixTrieNode) +
- zix_trie_pad(num_children) +
- (num_children * sizeof(ZixTrieNode*)));
-}
-
-ZIX_PRIVATE ZixTrieNode*
-realloc_node(ZixTrieNode* n, n_edges_t num_children)
-{
- return (ZixTrieNode*)realloc(n, zix_trie_node_size(num_children));
-}
-
-ZixTrie*
-zix_trie_new(void)
-{
- ZixTrie* t = (ZixTrie*)calloc(1, sizeof(ZixTrie));
-
- t->root = (ZixTrieNode*)calloc(1, sizeof(ZixTrieNode));
-
- return t;
-}
-
-ZIX_PRIVATE void
-zix_trie_free_rec(ZixTrieNode* n)
-{
- if (n) {
- for (n_edges_t i = 0; i < n->num_children; ++i) {
- zix_trie_free_rec(*zix_trie_get_child_ptr(n, i));
- }
- free(n);
- }
-}
-
-void
-zix_trie_free(ZixTrie* t)
-{
- zix_trie_free_rec(t->root);
- free(t);
-}
-
-ZIX_PRIVATE inline bool
-trie_is_leaf(const ZixTrieNode* n)
-{
- return n->num_children == 0;
-}
-
-ZIX_PRIVATE bool
-trie_find_edge(const ZixTrieNode* n, const uint8_t c, n_edges_t* const index)
-{
- *index = zix_trie_find_key(n->children, n->num_children, c);
- return *index < n->num_children && n->children[*index] == c;
-}
-
-#ifndef NDEBUG
-ZIX_PRIVATE bool
-zix_trie_node_check(ZixTrieNode* const n)
-{
- for (n_edges_t i = 0; i < n->num_children; ++i) {
- assert(n->children[i] != '\0');
- assert(*zix_trie_get_child_ptr(n, i) != NULL);
- }
- return true;
-}
-#endif
-
-ZIX_PRIVATE size_t
-zix_trie_add_child(ZixTrieNode** n_ptr,
- ZixTrieNode* child,
- const uint8_t first)
-{
- ZixTrieNode* n = *n_ptr;
-
- n = realloc_node(n, n->num_children + 1);
-#ifdef ZIX_TRIE_LINEAR_SEARCH
- const n_edges_t l = n->num_children;
- memmove(n->children + zix_trie_pad(n->num_children + 1),
- n->children + zix_trie_pad(n->num_children),
- n->num_children * sizeof(ZixTrieNode*));
- ++n->num_children;
- n->children[n->num_children - 1] = first;
- *zix_trie_get_child_ptr(n, n->num_children - 1) = child;
-#else
- const n_edges_t l = zix_trie_find_key(n->children, n->num_children, first);
- ZixTrieNode* m = (ZixTrieNode*)malloc(zix_trie_node_size(n->num_children + 1));
- m->str = n->str;
- m->num_children = n->num_children + 1;
-
- memcpy(m->children, n->children, l);
- m->children[l] = first;
- memcpy(m->children + l + 1, n->children + l, n->num_children - l);
-
- memcpy(zix_trie_get_child_ptr(m, 0),
- zix_trie_get_child_ptr(n, 0),
- l * sizeof(ZixTrieNode*));
- *zix_trie_get_child_ptr(m, l) = child;
- memcpy(zix_trie_get_child_ptr(m, l + 1),
- zix_trie_get_child_ptr(n, l),
- (n->num_children - l) * sizeof(ZixTrieNode*));
- free(n);
- n = m;
-#endif
-
- *n_ptr = n;
-
- assert(zix_trie_node_check(n));
- //assert(zix_trie_node_check(child));
-
- return l;
-}
-
-ZIX_PRIVATE ZixTrieNode**
-trie_insert_tail(ZixTrieNode** n_ptr,
- const uint8_t* str,
- const uint8_t* first,
- const size_t ZIX_UNUSED(len))
-{
- assert(first[0]);
- ZixTrieNode* c = NULL;
- while (first[0]) {
- assert(zix_trie_node_check(*n_ptr));
-
- c = realloc_node(NULL, 1);
- if (!c) {
- return NULL;
- }
-
- c->str = NULL;
- c->num_children = 0;
-
- const size_t l = zix_trie_add_child(n_ptr, c, first[0]);
- n_ptr = zix_trie_get_child_ptr(*n_ptr, l);
- assert(*n_ptr == c);
-
- ++first;
- }
-
- if (!c) {
- return NULL;
- }
-
- c->num_children = 0;
- c->str = str;
- assert(zix_trie_node_check(c));
- assert(*n_ptr == c);
- return n_ptr;
-}
-
-ZIX_PRIVATE ZixStatus
-trie_insert_internal(ZixTrieNode** n_ptr,
- const uint8_t* str,
- const uint8_t* first,
- const size_t len)
-{
- assert(zix_trie_node_check(*n_ptr));
- ZixTrieNode* n = *n_ptr;
- n_edges_t child_i;
- while (trie_find_edge(n, first[0], &child_i)) {
- assert(child_i <= n->num_children);
- ZixTrieNode** const child_ptr = zix_trie_get_child_ptr(n, child_i);
- ZixTrieNode* const child = *child_ptr;
- assert(child_ptr);
-
- assert(zix_trie_node_check(child));
-
- if (!first[0]) {
- /* Reached end of search string */
- if (child->str) {
- /* Found exact string in trie. */
- return ZIX_STATUS_EXISTS;
- } else {
- /* Set node value to inserted string */
- child->str = str;
- return ZIX_STATUS_SUCCESS;
- }
- } else {
- /* Didn't reach end of search string */
- if (trie_is_leaf(n)) {
- /* Hit leaf early, insert underneath */
- ZixTrieNode** c = trie_insert_tail(n_ptr, str, first, len);
- assert(zix_trie_node_check(*n_ptr));
- assert(zix_trie_node_check(*c));
- (void)c;
- return ZIX_STATUS_SUCCESS;
- } else {
- /* Match at this node, continue search downwards (or match) */
- n_ptr = child_ptr;
- assert(*n_ptr);
- n = *n_ptr;
- assert(n == child);
- ++first;
- }
- }
- }
-
- if (!first[0]) {
- if ((*n_ptr)->str) {
- return ZIX_STATUS_EXISTS;
- } else {
- (*n_ptr)->str = str;
- return ZIX_STATUS_SUCCESS;
- }
- }
-
- /* Hit leaf early, insert underneath */
- assert(zix_trie_node_check(*n_ptr));
- ZixTrieNode** c = trie_insert_tail(n_ptr, str, first, len);
- assert(zix_trie_node_check(*n_ptr));
- assert(zix_trie_node_check(*c));
- (void)c;
- return ZIX_STATUS_SUCCESS;
-}
-
-ZixStatus
-zix_trie_insert(ZixTrie* t, const char* str, size_t len)
-{
- assert(strlen(str) == len);
-
- const uint8_t* ustr = (const uint8_t*)str;
- return trie_insert_internal(&t->root, ustr, ustr, len);
-}
-
-ZixStatus
-zix_trie_find(const ZixTrie* t, const char* const str, const char** match)
-{
- ZixTrieNode* n = t->root;
- const char* p = str;
- n_edges_t child_i;
-
- while (trie_find_edge(n, p[0], &child_i)) {
- assert(child_i <= n->num_children);
- ZixTrieNode* const child = *zix_trie_get_child_ptr(n, child_i);
-
- ++p;
-
- if (!*p) {
- /* Reached end of search string */
- if (child->str) {
- /* Found exact string in trie. */
- *match = (const char*)child->str;
- return ZIX_STATUS_SUCCESS;
- } else {
- /* Prefix match, but exact string not present. */
- return ZIX_STATUS_NOT_FOUND;
- }
- } else {
- /* Didn't reach end of search string */
- if (trie_is_leaf(n)) {
- /* Hit leaf early, no match */
- return ZIX_STATUS_NOT_FOUND;
- } else {
- /* Match at this node, continue search downwards (or match) */
- n = child;
- }
- }
- }
-
- return ZIX_STATUS_NOT_FOUND;
-}
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