/* * (c) Copyright 1990-1996 OPEN SOFTWARE FOUNDATION, INC. * (c) Copyright 1990-1996 HEWLETT-PACKARD COMPANY * (c) Copyright 1990-1996 DIGITAL EQUIPMENT CORPORATION * (c) Copyright 1991, 1992 Siemens-Nixdorf Information Systems * To anyone who acknowledges that this file is provided "AS IS" without * any express or implied warranty: permission to use, copy, modify, and * distribute this file for any purpose is hereby granted without fee, * provided that the above copyright notices and this notice appears in * all source code copies, and that none of the names listed above be used * in advertising or publicity pertaining to distribution of the software * without specific, written prior permission. None of these organizations * makes any representations about the suitability of this software for * any purpose. */ /* * Header file for generic list functions operating on singly linked * null-terminated lists. Items may not be REMOVED from the list! The * intent is that the list can be traversed (for read-only operations) * without locking, since insertion is "safe" (though not truely * atomic). THIS ASSUMES THAT THE HARDWARE MAKES WRITES VISIBLE TO READS * IN THE ORDER IN WHICH THEY OCCURRED! WITHOUT SUCH READ/WRITE * ORDERING, IT MAY BE NECESSARY TO INSERT "BARRIERS" TO PRODUCE THE * REQUIRED VISIBILITY! */ #ifndef CMA_LIST #define CMA_LIST /* * INCLUDE FILES */ #include <cma.h> /* * CONSTANTS AND MACROS */ #define cma__c_null_list ((cma__t_list *)cma_c_null_ptr) /* * Test whether a list is empty. Return cma_c_true if so, else * cma_c_false. */ #define cma__list_empty(head) ((head)->link == cma__c_null_list) /* * Initialize a queue header to empty. */ #define cma__list_init(head) (void)((head)->link = cma__c_null_list) /* * Insert an element in a list following the specified item (or at the * beginning of the list if "list" is the list head). NOTE: insertion * operations should be interlocked by the caller! */ #define cma__list_insert(element,list) (void)( \ (element)->link = (list)->link, \ (list)->link = (element)) /* * Return the next item in a list (or the first, if the address is of the * list header) */ #define cma__list_next(element) ((element)->link) /* * TYPEDEFS */ typedef struct CMA__T_LIST { struct CMA__T_LIST *link; /* Forward link */ } cma__t_list; /* * GLOBAL DATA */ /* * INTERNAL INTERFACES */ #endif