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Sort text data by soundex value

Sort text data by soundex value

#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>

#define PACKAGE "sndsort"
#define VERSION "0.0.2"
#define MAXLINE 1024

struct lnode {
 char *str;
 int sndval;
 struct lnode *next;
};

struct lnode *insert(char *data, int val, struct lnode *list);
char *soundex(char *str);
void free_list(struct lnode *list);
void print_list(struct lnode *list, int x);
void print_help(int exval);

int main(int argc, char *argv[]) {
 FILE *fp = stdin;   /* read input from... (default is stdin) */
 struct lnode *list; /* linked list */
 char line[MAXLINE]; /* buff for fgets() */
 int sval = 0;       /* return value from soundex() */
 int len = 0;        /* initial line length */
 int opt = 0;        /* holds getopt option nr ... */
 int min_len = 2;    /* ignore lines Shorter as length (default=2) */
 int max_len = 20;   /* ignore lines Longer  as length (default=20) */
 int out_sndx_flag = 0;  /* output the `soundex value' for each string */
 int strip_nl_flag = 0;  /* strip trailing newlines from input */

 while((opt = getopt(argc, argv, "hvxsn:N:f:")) != -1) {
  switch(opt) {
   case 'h':
    print_help(0);
    break;
   case 'v':
   exit(0);
    break;
   case 'x':
    out_sndx_flag = 1;
    break;
   case 's':
    strip_nl_flag = 1;
    break;
   case 'n':
    min_len = atoi(optarg);
    break;
   case 'N':
    max_len = atoi(optarg);
    break;
   case 'f':
    if(freopen(optarg, "r", fp) == NULL) {
     fprintf(stderr, "%s: Error - opening `%s'\n", PACKAGE, optarg);
     return 1;
    }
    break;
   case ':':
    fprintf(stderr, "%s: Error - Option `%c' needs an argument\n\n", PACKAGE, optopt);
    print_help(1);
   case '?':
    fprintf(stderr, "%s: Error - No such option: `%c'\n\n", PACKAGE, optopt);
    print_help(1);
  } /* switch */
 } /* while */

 list = NULL;
 while((fgets(line, MAXLINE, stdin)) != NULL) {
  len = strlen(line);

  /* skip lines shorter as ``min_len'' in length */
  if(len < min_len || len > max_len) continue;

  /* strip trailing newlines */
  if(strip_nl_flag == 1 && line[len - 1] == '\n')
   line[len - 1] = '\0';

  /* reverse line[] buffer */
  sval = atoi(soundex(line)); 
  /* insert line in the linked list */
  list = insert(line, sval, list);
 }

 print_list(list, out_sndx_flag);
 free_list(list);

 fclose(fp);
 return 0;
}

struct lnode *insert(char *data, int sval, struct lnode *list) {
 struct lnode *p;
 struct lnode *q;

 /* create a new node */
 p = (struct lnode *)malloc(sizeof(struct lnode));
 /* save data into new node */
 p->str = strdup(data);
 p->sndval = sval;

 /* first, we handle the case where `data' should be the first element */
 if(list == NULL || list->sndval > sval) {
  /* apperently this !IS! the first element */
  /* now data should [be|becomes] the first element */
  p->next = list;
  return p;
 } else {  
  /* search the linked list for the right location */
  q = list;
  while(q->next != NULL && q->next->sndval < sval) {
   q = q->next;
  }
  p->next = q->next;
  q->next = p;
  return list;
 }
}
    
void free_list(struct lnode *list) {
 struct lnode *p;

 while(list != NULL) {
  p = list->next;
  free(list->str);
  free(list);
  list = p;
 }
}
  
void print_list(struct lnode *list, int x) {
 struct lnode *p;
  
 for(p = list; p != NULL; p = p->next)
  if(x == 1)
   printf("%8d %s\n", p->sndval, p->str);
  else
   printf("%s\n", p->str);
}

/* get soundex code for a string */
char *soundex(char *str) {
 static char soundexbuf[81];
 /* 
 // basicly ripped this piece of the code straight 
 // from the book... ehum.. sorry...
 */
 char *table = "01230120022455012623010202";
 char *sdx = soundexbuf, lastchr = ' ';

 while(*str) {
  if(isalpha(*str) && (*str != lastchr)) {
   *sdx = *(table + toupper(*str) - 'A');
   if((*sdx != '0') && (*sdx != lastchr))
    lastchr = *sdx++; 
  }
  str++; 
 }

 *sdx = '\0';
 return &soundexbuf[0];
}

void print_help(int exval) {
 printf("%s,%s sort text data by soundex value\n", PACKAGE, VERSION);
 printf("Usage: %s [-h] [-v] [-x] [-s] [-n INT] [-N INT] [-f FILE]\n\n", PACKAGE);

 printf(" -h        print this help and exit\n");
 printf(" -v        print version and exit\n\n");

 printf(" -x        output the `soundex value' with each string\n");
 printf(" -s        strip trailing newlines\n");
 printf(" -n INT    ignore lines Shorter as `INT' (default=2)\n");
 printf(" -N INT    ignore lines Longer  as `INT' (default=20)\n");
 printf(" -f FILE   read input from `FILE' (default=stdin)\n\n");
 exit(exval);
}