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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
#include "symbol-table.h"
#define TABLE_SIZE 256
symtab *hash_table[TABLE_SIZE];
extern int linenumber;
int HASH(char *str) {
int idx = 0;
while (*str) {
idx = idx << 1;
idx += *str;
str++;
}
return (idx & (TABLE_SIZE-1));
}
/* returns the symbol table entry if found else NULL */
symtab *lookup(char *name) {
int hash_key;
symtab *symptr;
if (!name)
return NULL;
hash_key = HASH(name);
symptr = hash_table[hash_key];
while (symptr) {
if (!(strcmp(name, symptr->lexeme)))
return symptr;
symptr = symptr->front;
}
return NULL;
}
void insertID(char *name) {
int hash_key;
symtab *ptr;
symtab *symptr = malloc(sizeof(symtab));
hash_key = HASH(name);
ptr = hash_table[hash_key];
if (ptr == NULL) {
/* first entry for this hash_key */
hash_table[hash_key] = symptr;
symptr->front = NULL;
symptr->back = symptr;
} else {
symptr->front = ptr;
ptr->back = symptr;
symptr->back = symptr;
hash_table[hash_key] = symptr;
}
strcpy(symptr->lexeme, name);
symptr->line = linenumber;
symptr->counter = 1;
}
void printSym(symtab *ptr) {
printf(" Name = %s \n", ptr->lexeme);
printf(" References = %d \n", ptr->counter);
}
void printSymTab(void) {
puts("----- Symbol Table ---------");
for (int i = 0; i < TABLE_SIZE; i++)
{
symtab *symptr;
symptr = hash_table[i];
while (symptr != NULL)
{
printf("====> index = %d\n", i);
printSym(symptr);
symptr = symptr->front;
}
}
}
symtab **fillTab(int *len) {
int cnt = 0;
for (int i = 0; i < TABLE_SIZE; i++)
{
symtab *symptr = hash_table[i];
while (symptr != NULL)
{
cnt++;
symptr = symptr->front;
}
}
symtab **tp = malloc(sizeof(symtab*)*cnt);
cnt = 0;
for (int i = 0; i < TABLE_SIZE; i++)
{
symtab *symptr = hash_table[i];
while (symptr != NULL)
{
tp[cnt++] = symptr;
symptr = symptr->front;
}
}
*len = cnt;
return tp;
}
// vim: set sw=4 ts=4 sts=4 et:
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