genstructs/slinkedlist.c

   1 /*
   2  * Compile with:
   3  * gcc slinkedlist.c -o slinkedlist -Wall -W -Wextra -ansi -pedantic
   4  */
   5
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <sys/queue.h>
  10
  11 SLIST_HEAD(listhead, entry) head;
  12
  13 struct entry {
  14     SLIST_ENTRY(entry) entries;
  15     const char *str;
  16 } *np, *n;
  17
  18 int main(void)
  19 {
  20     const char *str[] = { "this", "is", "a", "single", "linked", "list" };
  21     unsigned int i;
  22
  23     /* Initialize list */
  24     SLIST_INIT(&head);
  25
  26     /* Populate list with str[] items */
  27     for (i = 0; i < sizeof str / sizeof *str; i++) {
  28         if ((n = malloc(sizeof(struct entry))) == NULL) {
  29             perror("malloc()");
  30             goto CLEANUP_AND_EXIT;
  31         }
  32         n->str = str[i];
  33
  34         if (i == 0)
  35             SLIST_INSERT_HEAD(&head, n, entries);
  36         else
  37             SLIST_INSERT_AFTER(np, n, entries);
  38         np = n;
  39     }
  40
  41     /* Traverse list */
  42     SLIST_FOREACH(np, &head, entries)
  43         printf("%s\n", np->str);
  44
  45  CLEANUP_AND_EXIT:;
  46     /* Delete all elements */
  47     while (SLIST_FIRST(&head) != NULL) {
  48         np = SLIST_FIRST(&head);
  49         SLIST_REMOVE_HEAD(&head, entries);
  50         free(np);
  51     }
  52
  53     return EXIT_SUCCESS;
  54 }