/*++ /* NAME /* inet_addr_list 3 /* SUMMARY /* internet address list manager /* SYNOPSIS /* #include /* /* void inet_addr_list_init(list) /* INET_ADDR_LIST *list; /* /* void inet_addr_list_append(list,addr) /* INET_ADDR_LIST *list; /* struct in_addr *addr; /* /* void inet_addr_list_uniq(list) /* INET_ADDR_LIST *list; /* /* void inet_addr_list_free(list) /* INET_ADDR_LIST *list; /* DESCRIPTION /* This module maintains simple lists of internet addresses. /* /* inet_addr_list_init() initializes a user-provided structure /* so that it can be used by inet_addr_list_append() and by /* inet_addr_list_free(). /* /* inet_addr_list_append() appends the specified address to /* the specified list, extending the list on the fly. /* /* inet_addr_list_uniq() sorts the specified address list and /* eliminates duplicates. /* /* inet_addr_list_free() reclaims memory used for the /* specified address list. /* LICENSE /* .ad /* .fi /* The Secure Mailer license must be distributed with this software. /* AUTHOR(S) /* Wietse Venema /* IBM T.J. Watson Research /* P.O. Box 704 /* Yorktown Heights, NY 10598, USA /*--*/ /* System library. */ #include #include #include #include /* Utility library. */ #include #include #include /* inet_addr_list_init - initialize internet address list */ void inet_addr_list_init(INET_ADDR_LIST *list) { list->used = 0; list->size = 2; list->addrs = (struct in_addr *) mymalloc(sizeof(*list->addrs) * list->size); } /* inet_addr_list_append - append address to internet address list */ void inet_addr_list_append(INET_ADDR_LIST *list, struct in_addr * addr) { char *myname = "inet_addr_list_append"; if (msg_verbose > 1) msg_info("%s: %s", myname, inet_ntoa(*addr)); if (list->used >= list->size) list->size *= 2; list->addrs = (struct in_addr *) myrealloc((char *) list->addrs, sizeof(*list->addrs) * list->size); list->addrs[list->used++] = *addr; } /* inet_addr_list_comp - compare addresses */ static int inet_addr_list_comp(const void *a, const void *b) { const struct in_addr *a_addr = (const struct in_addr *) a; const struct in_addr *b_addr = (const struct in_addr *) b; return (a_addr->s_addr - b_addr->s_addr); } /* inet_addr_list_uniq - weed out duplicates */ void inet_addr_list_uniq(INET_ADDR_LIST *list) { int n; int m; /* * Put the identical members right next to each other. */ qsort((void *) list->addrs, list->used, sizeof(list->addrs[0]), inet_addr_list_comp); /* * Nuke the duplicates. Postcondition after while loop: m is the largest * index for which list->addrs[n] == list->addrs[m]. */ for (m = n = 0; m < list->used; m++, n++) { if (m != n) list->addrs[n] = list->addrs[m]; while (m + 1 < list->used && inet_addr_list_comp((void *) &(list->addrs[n]), (void *) &(list->addrs[m + 1])) == 0) m += 1; } list->used = n; } /* inet_addr_list_free - destroy internet address list */ void inet_addr_list_free(INET_ADDR_LIST *list) { myfree((char *) list->addrs); } #ifdef TEST /* * Duplicate elimination needs to be tested. */ #include static void inet_addr_list_print(INET_ADDR_LIST *list) { int n; for (n = 0; n < list->used; n++) msg_info("%s", inet_ntoa(list->addrs[n])); } int main(int argc, char **argv) { INET_ADDR_LIST list; inet_addr_list_init(&list); while (--argc && *++argv) if (inet_addr_host(&list, *argv) == 0) msg_fatal("host not found: %s", *argv); msg_info("list before sort/uniq"); inet_addr_list_print(&list); inet_addr_list_uniq(&list); msg_info("list after sort/uniq"); inet_addr_list_print(&list); inet_addr_list_free(&list); return (0); } #endif