[Memory issues]

I have a bit of a problem here. I'm fairly new in programming in c but i can write some simple programs.

 

 

What i wrote is a program that simply encodes my php scripts en decodes them again with the right password. This worked fine when i ran the code just as a c executeable.

Now i made a php function of this c code. The only problem is, that when i keep executing my php script the memory keeps remembering my previous values:

 

The code i run throught zend_eval_string (after it's decoded) is:

 

?><?PHP

echo 'good';

?>

 

the output of this script is for the first time:

 

good

 

the second time:

 

good?>good

 

the third time:

 

good?>good?>good

 

and so on.

 

So the question i have, how can i succesfully fill the memory for just ones and free it after executing my script.

 

 

The important pieces of code:

 

char * decrypt(char *content)
{
struct hashdata h[NOOFKEY];
FILE *df1;
char c, ch, buf[BUFSIZ], line[BUFSIZ];
int i,x;
char * rStr = (char *) malloc(strlen(content));
x = 0;
strcat(line,"?>");
for (i=0;i<NOOFKEY;i++)
   readEncryptKey(&h[i]);

strncpy(&c,content+x,1);
while(c != '\0')
  {
  x++;
  for(i=0;i<NOOFKEY;i++)
     c = hash(&h[i],c);
  sprintf(buf,"%c",c);
  strncpy(&c,content+x,1);
  strcat(line,buf);
  }
strcpy(rStr,line);
return rStr;
free(rStr);
}

/* implement function that is meant to be made available to PHP */
ZEND_FUNCTION(meradecode)
{
char *parameter;
int parameter_len;
if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &parameter, &parameter_len) == FAILURE)
   return;

zend_eval_string(decrypt(parameter),NULL,"Meraweb Encoder");
/*RETURN_STRING(decrypt(parameter),0);*/
free(parameter);
}