terom@35: #ifndef CHAIN_H
terom@35: #define CHAIN_H
terom@35: 
terom@35: /**
terom@87:  * @file
terom@35:  *
terom@171:  * Defines a brain-dead auto-allocated linked list for simple uses.
terom@35:  */
terom@35: #include "error.h"
terom@35: #include <sys/queue.h>
terom@171: #include <stdlib.h>
terom@171: #include <stdbool.h>
terom@35: 
terom@35: /**
terom@171:  * Header entry to embed a chain_item
terom@35:  */
terom@171: #define CHAIN_ITEM_HEADER(type) TAILQ_ENTRY(type) _chain_list
terom@35: 
terom@35: /**
terom@171:  * Header entry to embed a chain_head
terom@35:  */
terom@171: #define CHAIN_HEAD_TYPE(head_type, item_type) \
terom@171:     struct head_type {  \
terom@171:         TAILQ_HEAD(head_type ## _head, item_type) head;  \
terom@171:     }
terom@35: 
terom@35: /**
terom@171:  * Generic chain_head type
terom@69:  */
terom@171: struct _chain_item {
terom@171:    TAILQ_ENTRY(_chain_item) _chain_list;
terom@171: };
terom@171: 
terom@171: TAILQ_HEAD(_chain_head, _chain_item);
terom@69: 
terom@69: /**
terom@171:  * Cast to a chain_item
terom@35:  */
terom@171: #define CHAIN_CAST_ITEM(item_ptr) &(item_ptr)->_chain_list
terom@171: 
terom@171: /**
terom@171:  * Ref the head struct from the given chain_head
terom@171:  */
terom@171: #define CHAIN_DEREF_HEAD(head_ptr) &(head_ptr)->head
terom@171: 
terom@171: /**
terom@171:  * Cast to a generic _chain_head
terom@171:  */
terom@171: #define CHAIN_HEAD_GENERIC(head_ptr) (struct _chain_head *) CHAIN_DEREF_HEAD(head_ptr)
terom@171: 
terom@171: /**
terom@171:  * Evaluates to the type of the given CHAIN_HEAD
terom@171:  */
terom@171: #define CHAIN_TYPE(head_ptr) typeof (*TAILQ_FIRST(CHAIN_DEREF_HEAD(head_ptr)))
terom@171: 
terom@171: 
terom@171: 
terom@171: /**
terom@171:  * Initialize a chain_head to be empty
terom@171:  */
terom@171: #define CHAIN_INIT(head_ptr) TAILQ_INIT(CHAIN_DEREF_HEAD(head_ptr))
terom@171: 
terom@171: 
terom@171: /**
terom@171:  * Return the first item in the chain as a pointer of the correct type
terom@171:  */
terom@171: #define CHAIN_FIRST(head_ptr) TAILQ_FIRST(CHAIN_DEREF_HEAD(head_ptr))
terom@171: 
terom@171: /**
terom@171:  * Return the item after the given item
terom@171:  */
terom@171: #define CHAIN_NEXT(item_ptr) TAILQ_NEXT(item_ptr, _chain_list)
terom@171: 
terom@171: 
terom@171: 
terom@171: /**
terom@171:  * Allocate a new chain_item of the given type, adding it to the beginning of the list, and returning a calloc'd
terom@171:  * struct of the given type.
terom@171:  */
terom@171: #define CHAIN_ADD_HEAD(head_ptr) (CHAIN_TYPE(head_ptr) *) _chain_add(CHAIN_HEAD_GENERIC(head_ptr), false, sizeof (*CHAIN_TYPE(head_ptr)))
terom@171: 
terom@171: /**
terom@171:  * Same as CHAIN_ADD_HEAD, except this adds the new item to the end of the list.
terom@171:  */
terom@171: #define CHAIN_ADD_TAIL(head_ptr) (CHAIN_TYPE(head_ptr) *) _chain_add(CHAIN_HEAD_GENERIC(head_ptr), true,  sizeof (CHAIN_TYPE(head_ptr)))
terom@171: 
terom@171: 
terom@171: 
terom@171: /**
terom@171:  * Iterate over the items in a chain
terom@171:  */
terom@171: #define CHAIN_FOREACH(head_ptr, item_ptr) TAILQ_FOREACH(item_ptr, CHAIN_DEREF_HEAD(head_ptr), _chain_list)
terom@171: 
terom@171: /**
terom@171:  * Safely iterate over the items in a chain, such that the iterated-over item can be removed without breaking the chain
terom@171:  */
terom@171: #define CHAIN_FOREACH_SAFE(head_ptr, item_ptr) \
terom@171:     for (   \
terom@171:             typeof (item_ptr) _chain_next = CHAIN_FIRST(head_ptr); \
terom@171:             ((void) ((item_ptr = _chain_next) && (_chain_next = CHAIN_NEXT(_chain_next)))), item_ptr; \
terom@171:             (void) 0  \
terom@171:     )
terom@171: 
terom@171: 
terom@171: /**
terom@171:  * Remove an item from the list and free it.
terom@171:  */
terom@171: #define CHAIN_DELETE(head_ptr, item_ptr) \
terom@171:     do {    \
terom@171:         TAILQ_REMOVE(CHAIN_DEREF_HEAD(head_ptr), item_ptr, _chain_list);    \
terom@171:         free(item_ptr); \
terom@171:     } while (0);
terom@171: 
terom@171: /**
terom@171:  * Delete the items from the chain for which the given predicate matches
terom@171:  */
terom@171: #define CHAIN_DELETE_WHICH(head_ptr, item_ptr, predicate) \
terom@171:     do {    \
terom@171:         CHAIN_FOREACH_SAFE(head_ptr, item_ptr)  \
terom@171:             if (predicate)  \
terom@171:                 CHAIN_DELETE(head_ptr, item_ptr);   \
terom@171:     } while (0)
terom@171: 
terom@171: /**
terom@171:  * Delete all items from the chain
terom@171:  */
terom@171: #define CHAIN_CLEAR(head_ptr) \
terom@171:     do {    \
terom@171:         CHAIN_TYPE(head_ptr) *_chain_item;   \
terom@171:         CHAIN_FOREACH_SAFE(head_ptr, _chain_item)   \
terom@171:            free(_chain_item);   \
terom@171:     } while (0);
terom@171: 
terom@171: 
terom@171: 
terom@171: void *_chain_add (struct _chain_head *head, bool tail, size_t size);
terom@35: 
terom@35: #endif