return NULL on out of memory

char *curl_escape(const char *string, int length)

{

  size_t alloc = (length?(size_t)length:strlen(string))+1;  

  char *ns = malloc(alloc);

  char *ns;

  char *testing_ptr = NULL;

  unsigned char in;

  size_t newlen = alloc;

  int strindex=0;

  ns = malloc(alloc);

  if(!ns)

    return NULL;

  length = alloc-1;

  while(length--) {

    in = *string;

  int strindex=0;

  long hex;

  if( !ns ) {

  if( !ns )

    return NULL;

  }  

  while(--alloc > 0) {

    in = *string;