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#include "symtab.h"
#include <stdlib.h>
#include <string.h>
unsigned int hash(char *s) {
uint32_t hv = 0;
for( int i = 0; s[i] != '\0'; i++ ) {
// take MSB 6 bits of hv and xors with LSB of s[i]
uint32_t v = ( hv >> 26 ) ^ (s[i] & 0x3f);
// Push those back on hv
hv = (hv << 4) | v;
}
// Return appropriate size
return hv % HASHSIZE;
}
symnode_t *sym_insert(char *var) {
unsigned int index = hash(var);
// Save old value
symnode_t *oldSym = symbolarray[index];
// Make new
symbolarray[index] = malloc(sizeof(symnode_t));
if( symbolarray[index] == NULL ) {
// If malloc failed
symbolarray[index] = oldSym;
return NULL;
}
// Link old one
symbolarray[index]->next = oldSym;
symbolarray[index]->name = var;
return symbolarray[index];
}
symnode_t *sym_lookup(char *var) {
unsigned int index = hash(var);
symnode_t *n = symbolarray[index];
// Look trough list
while(n != NULL && strcmp(n->name, var) != 0) {
n = n->next;
}
return n;
}
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