summaryrefslogtreecommitdiff
path: root/misc/src/common/db.c
diff options
context:
space:
mode:
Diffstat (limited to 'misc/src/common/db.c')
-rw-r--r--misc/src/common/db.c500
1 files changed, 500 insertions, 0 deletions
diff --git a/misc/src/common/db.c b/misc/src/common/db.c
new file mode 100644
index 0000000..a2dc695
--- /dev/null
+++ b/misc/src/common/db.c
@@ -0,0 +1,500 @@
+// $Id: db.c,v 1.2 2004/09/23 14:43:06 MouseJstr Exp $
+// #define MALLOC_DBN
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "db.h"
+#include "utils.h"
+
+#ifdef MEMWATCH
+#include "memwatch.h"
+#endif
+
+#define ROOT_SIZE 4096
+#ifdef MALLOC_DBN
+static struct dbn *dbn_root[512], *dbn_free;
+static int dbn_root_rest=0,dbn_root_num=0;
+
+static void * malloc_dbn(void)
+{
+ struct dbn* ret;
+
+ if(dbn_free==NULL){
+ if(dbn_root_rest<=0){
+ CREATE(dbn_root[dbn_root_num], struct dbn, ROOT_SIZE);
+
+ dbn_root_rest=ROOT_SIZE;
+ dbn_root_num++;
+ }
+ return &(dbn_root[dbn_root_num-1][--dbn_root_rest]);
+ }
+ ret=dbn_free;
+ dbn_free = dbn_free->parent;
+ return ret;
+}
+
+static void free_dbn(struct dbn* add_dbn)
+{
+ add_dbn->parent = dbn_free;
+ dbn_free = add_dbn;
+}
+#endif
+
+static int strdb_cmp(struct dbt* table,void* a,void* b)
+{
+ if(table->maxlen)
+ return strncmp(a,b,table->maxlen);
+ return strcmp(a,b);
+}
+
+static unsigned int strdb_hash(struct dbt* table,void* a)
+{
+ int i;
+ unsigned int h;
+ unsigned char *p=a;
+
+ i=table->maxlen;
+ if(i==0) i=0x7fffffff;
+ for(h=0;*p && --i>=0;){
+ h=(h*33 + *p++) ^ (h>>24);
+ }
+ return h;
+}
+
+struct dbt* strdb_init(int maxlen)
+{
+ int i;
+ struct dbt* table;
+
+ CREATE(table, struct dbt, 1);
+
+ table->cmp=strdb_cmp;
+ table->hash=strdb_hash;
+ table->maxlen=maxlen;
+ for(i=0;i<HASH_SIZE;i++)
+ table->ht[i]=NULL;
+ return table;
+}
+
+static int numdb_cmp(struct dbt* table,void* a,void* b)
+{
+ int ia,ib;
+
+ ia=(int)a;
+ ib=(int)b;
+
+ if((ia^ib) & 0x80000000)
+ return ia<0 ? -1 : 1;
+
+ return ia-ib;
+}
+
+static unsigned int numdb_hash(struct dbt* table,void* a)
+{
+ return (unsigned int)a;
+}
+
+struct dbt* numdb_init(void)
+{
+ int i;
+ struct dbt* table;
+
+ CREATE(table, struct dbt, 1);
+
+ table->cmp=numdb_cmp;
+ table->hash=numdb_hash;
+ table->maxlen=sizeof(int);
+ for(i=0;i<HASH_SIZE;i++)
+ table->ht[i]=NULL;
+ return table;
+}
+
+void* db_search(struct dbt *table,void* key)
+{
+ struct dbn *p;
+
+ for(p=table->ht[table->hash(table,key) % HASH_SIZE];p;){
+ int c=table->cmp(table,key,p->key);
+ if(c==0)
+ return p->data;
+ if(c<0)
+ p=p->left;
+ else
+ p=p->right;
+ }
+ return NULL;
+}
+
+void * db_search2(struct dbt *table, const char *key)
+{
+ int i,sp;
+ struct dbn *p,*pn,*stack[64];
+ int slen = strlen(key);
+
+ for(i=0;i<HASH_SIZE;i++){
+ if((p=table->ht[i])==NULL)
+ continue;
+ sp=0;
+ while(1){
+ if (strncasecmp(key, p->key, slen) == 0)
+ return p->data;
+ if((pn=p->left)!=NULL){
+ if(p->right){
+ stack[sp++]=p->right;
+ }
+ p=pn;
+ } else {
+ if(p->right){
+ p=p->right;
+ } else {
+ if(sp==0)
+ break;
+ p=stack[--sp];
+ }
+ }
+ }
+ }
+ return 0;
+}
+
+static void db_rotate_left(struct dbn *p,struct dbn **root)
+{
+ struct dbn * y = p->right;
+ p->right = y->left;
+ if (y->left !=0)
+ y->left->parent = p;
+ y->parent = p->parent;
+
+ if (p == *root)
+ *root = y;
+ else if (p == p->parent->left)
+ p->parent->left = y;
+ else
+ p->parent->right = y;
+ y->left = p;
+ p->parent = y;
+}
+
+static void db_rotate_right(struct dbn *p,struct dbn **root)
+{
+ struct dbn * y = p->left;
+ p->left = y->right;
+ if (y->right != 0)
+ y->right->parent = p;
+ y->parent = p->parent;
+
+ if (p == *root)
+ *root = y;
+ else if (p == p->parent->right)
+ p->parent->right = y;
+ else
+ p->parent->left = y;
+ y->right = p;
+ p->parent = y;
+}
+
+static void db_rebalance(struct dbn *p,struct dbn **root)
+{
+ p->color = RED;
+ while(p!=*root && p->parent->color==RED){ // rootは必ず黒で親は赤いので親の親は必ず存在する
+ if (p->parent == p->parent->parent->left) {
+ struct dbn *y = p->parent->parent->right;
+ if (y && y->color == RED) {
+ p->parent->color = BLACK;
+ y->color = BLACK;
+ p->parent->parent->color = RED;
+ p = p->parent->parent;
+ } else {
+ if (p == p->parent->right) {
+ p = p->parent;
+ db_rotate_left(p, root);
+ }
+ p->parent->color = BLACK;
+ p->parent->parent->color = RED;
+ db_rotate_right(p->parent->parent, root);
+ }
+ } else {
+ struct dbn* y = p->parent->parent->left;
+ if (y && y->color == RED) {
+ p->parent->color = BLACK;
+ y->color = BLACK;
+ p->parent->parent->color = RED;
+ p = p->parent->parent;
+ } else {
+ if (p == p->parent->left) {
+ p = p->parent;
+ db_rotate_right(p, root);
+ }
+ p->parent->color = BLACK;
+ p->parent->parent->color = RED;
+ db_rotate_left(p->parent->parent, root);
+ }
+ }
+ }
+ (*root)->color=BLACK;
+}
+
+static void db_rebalance_erase(struct dbn *z,struct dbn **root)
+{
+ struct dbn *y = z, *x = NULL, *x_parent = NULL;
+
+ if (y->left == NULL)
+ x = y->right;
+ else if (y->right == NULL)
+ x = y->left;
+ else {
+ y = y->right;
+ while (y->left != NULL)
+ y = y->left;
+ x = y->right;
+ }
+ if (y != z) { // 左右が両方埋まっていた時 yをzの位置に持ってきてzを浮かせる
+ z->left->parent = y;
+ y->left = z->left;
+ if (y != z->right) {
+ x_parent = y->parent;
+ if (x) x->parent = y->parent;
+ y->parent->left = x;
+ y->right = z->right;
+ z->right->parent = y;
+ } else
+ x_parent = y;
+ if (*root == z)
+ *root = y;
+ else if (z->parent->left == z)
+ z->parent->left = y;
+ else
+ z->parent->right = y;
+ y->parent = z->parent;
+ { int tmp=y->color; y->color=z->color; z->color=tmp; }
+ y = z;
+ } else { // どちらか空いていた場合 xをzの位置に持ってきてzを浮かせる
+ x_parent = y->parent;
+ if (x) x->parent = y->parent;
+ if (*root == z)
+ *root = x;
+ else if (z->parent->left == z)
+ z->parent->left = x;
+ else
+ z->parent->right = x;
+ }
+ // ここまで色の移動の除いて通常の2分木と同じ
+ if (y->color != RED) { // 赤が消える分には影響無し
+ while (x != *root && (x == NULL || x->color == BLACK))
+ if (x == x_parent->left) {
+ struct dbn* w = x_parent->right;
+ if (w->color == RED) {
+ w->color = BLACK;
+ x_parent->color = RED;
+ db_rotate_left(x_parent, root);
+ w = x_parent->right;
+ }
+ if ((w->left == NULL ||
+ w->left->color == BLACK) &&
+ (w->right == NULL ||
+ w->right->color == BLACK)) {
+ w->color = RED;
+ x = x_parent;
+ x_parent = x_parent->parent;
+ } else {
+ if (w->right == NULL ||
+ w->right->color == BLACK) {
+ if (w->left) w->left->color = BLACK;
+ w->color = RED;
+ db_rotate_right(w, root);
+ w = x_parent->right;
+ }
+ w->color = x_parent->color;
+ x_parent->color = BLACK;
+ if (w->right) w->right->color = BLACK;
+ db_rotate_left(x_parent, root);
+ break;
+ }
+ } else { // same as above, with right <-> left.
+ struct dbn* w = x_parent->left;
+ if (w->color == RED) {
+ w->color = BLACK;
+ x_parent->color = RED;
+ db_rotate_right(x_parent, root);
+ w = x_parent->left;
+ }
+ if ((w->right == NULL ||
+ w->right->color == BLACK) &&
+ (w->left == NULL ||
+ w->left->color == BLACK)) {
+ w->color = RED;
+ x = x_parent;
+ x_parent = x_parent->parent;
+ } else {
+ if (w->left == NULL ||
+ w->left->color == BLACK) {
+ if (w->right) w->right->color = BLACK;
+ w->color = RED;
+ db_rotate_left(w, root);
+ w = x_parent->left;
+ }
+ w->color = x_parent->color;
+ x_parent->color = BLACK;
+ if (w->left) w->left->color = BLACK;
+ db_rotate_right(x_parent, root);
+ break;
+ }
+ }
+ if (x) x->color = BLACK;
+ }
+}
+
+struct dbn* db_insert(struct dbt *table,void* key,void* data)
+{
+ struct dbn *p,*priv;
+ int c,hash;
+
+ hash = table->hash(table,key) % HASH_SIZE;
+ for(c=0,priv=NULL ,p = table->ht[hash];p;){
+ c=table->cmp(table,key,p->key);
+ if(c==0){ // replace
+ if (table->release)
+ table->release(p, 3);
+ p->data=data;
+ p->key=key;
+ return p;
+ }
+ priv=p;
+ if(c<0){
+ p=p->left;
+ } else {
+ p=p->right;
+ }
+ }
+#ifdef MALLOC_DBN
+ p=malloc_dbn();
+#else
+ CREATE(p, struct dbn, 1);
+#endif
+ if(p==NULL){
+ printf("out of memory : db_insert\n");
+ return NULL;
+ }
+ p->parent= NULL;
+ p->left = NULL;
+ p->right = NULL;
+ p->key = key;
+ p->data = data;
+ p->color = RED;
+ if(c==0){ // hash entry is empty
+ table->ht[hash] = p;
+ p->color = BLACK;
+ } else {
+ if(c<0){ // left node
+ priv->left = p;
+ p->parent=priv;
+ } else { // right node
+ priv->right = p;
+ p->parent=priv;
+ }
+ if(priv->color==RED){ // must rebalance
+ db_rebalance(p,&table->ht[hash]);
+ }
+ }
+ return p;
+}
+
+void* db_erase(struct dbt *table,void* key)
+{
+ void *data;
+ struct dbn *p;
+ int c,hash;
+
+ hash = table->hash(table,key) % HASH_SIZE;
+ for(c=0,p = table->ht[hash];p;){
+ c=table->cmp(table,key,p->key);
+ if(c==0)
+ break;
+ if(c<0)
+ p=p->left;
+ else
+ p=p->right;
+ }
+ if(!p)
+ return NULL;
+ data=p->data;
+ db_rebalance_erase(p,&table->ht[hash]);
+#ifdef MALLOC_DBN
+ free_dbn(p);
+#else
+ free(p);
+#endif
+ return data;
+}
+
+void db_foreach(struct dbt *table,int (*func)(void*,void*,va_list),...)
+{
+ int i,sp;
+ // red-black treeなので64個stackがあれば2^32個ノードまで大丈夫
+ struct dbn *p,*pn,*stack[64];
+ va_list ap;
+
+ va_start(ap,func);
+ for(i=0;i<HASH_SIZE;i++){
+ if((p=table->ht[i])==NULL)
+ continue;
+ sp=0;
+ while(1){
+ func(p->key,p->data,ap);
+ if((pn=p->left)!=NULL){
+ if(p->right){
+ stack[sp++]=p->right;
+ }
+ p=pn;
+ } else {
+ if(p->right){
+ p=p->right;
+ } else {
+ if(sp==0)
+ break;
+ p=stack[--sp];
+ }
+ }
+ }
+ }
+ va_end(ap);
+}
+
+void db_final(struct dbt *table,int (*func)(void*,void*,va_list),...)
+{
+ int i,sp;
+ struct dbn *p,*pn,*stack[64];
+ va_list ap;
+
+ va_start(ap,func);
+ for(i=0;i<HASH_SIZE;i++){
+ if((p=table->ht[i])==NULL)
+ continue;
+ sp=0;
+ while(1){
+ if(func)
+ func(p->key,p->data,ap);
+ if((pn=p->left)!=NULL){
+ if(p->right){
+ stack[sp++]=p->right;
+ }
+ } else {
+ if(p->right){
+ pn=p->right;
+ } else {
+ if(sp==0)
+ break;
+ pn=stack[--sp];
+ }
+ }
+#ifdef MALLOC_DBN
+ free_dbn(p);
+#else
+ free(p);
+#endif
+ p=pn;
+ }
+ }
+ free(table);
+ va_end(ap);
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-15 13:03:40 +0000