1 /* 2 * Initial implementation: 3 * Copyright (c) 2002 Robert Drehmel 4 * All rights reserved. 5 * 6 * As long as the above copyright statement and this notice remain 7 * unchanged, you can do what ever you want with this file. 8 * 9 * $FreeBSD: src/lib/libc/stdlib/insque.c,v 1.3 2003/01/04 07:34:41 tjr Exp $ 10 */ 11 12 #define _SEARCH_PRIVATE 13 #include <search.h> 14 #ifdef DEBUG 15 #include <stdio.h> 16 #else 17 #include <stdlib.h> /* for NULL */ 18 #endif 19 20 void 21 insque(void *element, void *pred) 22 { 23 struct que_elem *prev, *next, *elem; 24 25 elem = (struct que_elem *)element; 26 prev = (struct que_elem *)pred; 27 28 if (prev == NULL) { 29 elem->prev = elem->next = NULL; 30 return; 31 } 32 33 next = prev->next; 34 if (next != NULL) { 35 #ifdef DEBUG 36 if (next->prev != prev) { 37 fprintf(stderr, "insque: Inconsistency detected:" 38 " next(%p)->prev(%p) != prev(%p)\n", 39 next, next->prev, prev); 40 } 41 #endif 42 next->prev = elem; 43 } 44 prev->next = elem; 45 elem->prev = prev; 46 elem->next = next; 47 } 48