piler/src/hash.c
Janos SUTO 345fd715f5 cppcheck refactoring
Signed-off-by: Janos SUTO <sj@acts.hu>
2020-08-10 20:58:34 +02:00

164 lines
2.4 KiB
C

/*
* hash.c, SJ
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <piler.h>
inline int hash(unsigned int key){
return key % MAXHASH;
}
void inithash(struct node *xhash[]){
int i;
for(i=0;i<MAXHASH;i++){
xhash[i] = NULL;
}
}
void clearhash(struct node *xhash[]){
int i;
struct node *p, *q;
for(i=0;i<MAXHASH;i++){
q = xhash[i];
while(q != NULL){
p = q;
q = q->r;
if(p->str){
free(p->str);
}
free(p);
}
xhash[i] = NULL;
}
}
struct node *makenewnode(char *s){
struct node *h;
int len;
if(s == NULL) return NULL;
len = strlen(s);
if((h = malloc(sizeof(struct node))) == NULL) return NULL;
memset(h, 0, sizeof(struct node));
h->str = malloc(len+2);
if(h->str == NULL){
free(h);
return NULL;
}
memset(h->str, 0, len+2);
snprintf(h->str, len+1, "%s", s);
h->key = DJBHash(s, len);
h->r = NULL;
return h;
}
int addnode(struct node *xhash[], char *s){
struct node *p=NULL, *q;
unsigned int key = 0;
int len;
if(s == NULL) return 0;
len = strlen(s);
key = DJBHash(s, len);
if(xhash[hash(key)] == NULL){
xhash[hash(key)] = makenewnode(s);
}
else {
q = xhash[hash(key)];
while(q != NULL){
p = q;
if(p->key == key){
return 0;
}
else {
q = q->r;
}
}
if(p) p->r = makenewnode(s);
}
return 1;
}
struct node *findnode(struct node *xhash[], char *s){
struct node *q;
unsigned int key;
int len;
if(s == NULL) return NULL;
len = strlen(s);
key = DJBHash(s, len);
q = xhash[hash(key)];
if(q == NULL) return NULL;
while(q != NULL){
if(strcmp(q->str, s) == 0){
return q;
}
else {
q = q->r;
}
}
return NULL;
}
int is_substr_in_hash(struct node *xhash[], char *s){
int i;
struct node *q;
for(i=0;i<MAXHASH;i++){
q = xhash[i];
while(q != NULL){
if(q->str && strstr(s, q->str)) return 1;
q = q->r;
}
}
return 0;
}
unsigned int DJBHash(char* str, unsigned int len){
unsigned int hashval = 5381;
unsigned int i = 0;
for(i=0; i < len; str++, i++){
hashval = ((hashval << 5) + hashval) + (*str);
}
return hashval;
}