Compare two strings by soundex values

Compare two strings by soundex values

#include <stdio.h>
#include <error.h>

#define MAXLINE         1024

int sndxcode[26];
char *sndxgrp[] = { "aeiouhyw", "kcgjqsxz", "td",
                    "bpfv", "l", "mn", "r" };

void locsndx(char *, int *, char);
int cmpcodes(int *, int *);
int cmpsndx(char *, char *);

int main(int argc, char *argv[]) {
 char *ptr = NULL;
 int i = 0;

 if(argc != 3)
  error(1, 0, "string1 string2");

 for(i = sizeof(sndxgrp) / sizeof(char *) - 1; i >= 0; i--)
  for(ptr = sndxgrp[i]; *ptr; ptr++)
   sndxcode[*ptr - 'a'] = i;

 printf("%d\n", cmpsndx(argv[1], argv[2]));

 return 0;
}

void locsndx(char *str, int *sndx, char lastchar) {
 if(0 == *str)
  *sndx = -1, lastchar = 0;
 else if(*str == lastchar)
  locsndx(str + 1, sndx, lastchar);
 else if(-1 == lastchar)
  *sndx = sndxcode[*str - 'a'], locsndx(str + 1, sndx + 1, *str);
 else if(sndxcode[*str - 'a'] == 0)
  locsndx(str + 1, sndx, *str);
 else
  *sndx = sndxcode[*str - 'a'], locsndx(str + 1, sndx + 1, *str);

 return;
}

int cmpcodes(int *sndx1, int *sndx2) {
 int *ptr1 = sndx1;
 int *ptr2 = sndx2;

 for(; *ptr1 != -1 && *ptr2 != -1 && *ptr1 == *ptr2; ptr1++, ptr2++)
  ;

 return *ptr1 == *ptr2;
}

int cmpsndx(char *str1, char *str2) {
 int sndx1[MAXLINE] = {0};
 int sndx2[MAXLINE] = {0};

 locsndx(str1, sndx1, -1);
 locsndx(str2, sndx2, -1);

 return cmpcodes(sndx1, sndx2);
}