genstructs/slinkedlist.c

   1 /* compile with:
   2    gcc slinkedlist.c -o slinkedlist -Wall -W -Wextra -ansi -pedantic */
   3
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <sys/queue.h>
   8
   9 SLIST_HEAD(listhead, entry) head;
  10
  11 struct entry {
  12     SLIST_ENTRY(entry) entries;
  13     const char *str;
  14 } *np, *n;
  15
  16 int main(void)
  17 {
  18     const char *str[] = { "this", "is", "a", "single", "linked", "list" };
  19     unsigned int i;
  20
  21     /* Initialize list */
  22     SLIST_INIT(&head);
  23
  24     /* Populate list with str[] items */
  25     for (i = 0; i < sizeof str / sizeof *str; i++) {
  26         if ((n = malloc(sizeof(struct entry))) == NULL) {
  27             perror("malloc");
  28             goto CLEANUP_AND_EXIT;
  29         }
  30         n->str = str[i];
  31
  32         if (i == 0)
  33             SLIST_INSERT_HEAD(&head, n, entries);
  34         else
  35             SLIST_INSERT_AFTER(np, n, entries);
  36         np = n;
  37     }
  38
  39     /* Traverse list */
  40     SLIST_FOREACH(np, &head, entries)
  41         printf("%s\n", np->str);
  42
  43  CLEANUP_AND_EXIT:;
  44     /* Delete all elements */
  45     while (SLIST_FIRST(&head) != NULL) {
  46         np = SLIST_FIRST(&head);
  47         SLIST_REMOVE_HEAD(&head, entries);
  48         free(np);
  49     }
  50
  51     return EXIT_SUCCESS;
  52 }