/*
- silclist.h
+ silclist.h
Author: Pekka Riikonen <priikone@silcnet.org>
- Copyright (C) 2002 - 2003 Pekka Riikonen
+ Copyright (C) 2002 - 2008 Pekka Riikonen
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
*/
-/****h* silcutil/SILC List Interface
+/****h* silcutil/List Interface
*
* DESCRIPTION
*
- * Implementation of the SilcList interface. This interface provides
- * simple linked list.
+ * Generic list interface that can turn any structure with list pointers
+ * into a SilcList. The interface can provide both singly and doubly linked
+ * lists. The interface does not allocate any memory.
+ *
+ * SILC List is not thread-safe. If the same list context must be used
+ * in multithreaded environment concurrency control must be employed.
+ *
+ * EXAMPLE
+ *
+ * struct EntryStruct {
+ * char *dummy;
+ * struct EntryStruct *next; // The list member pointer
+ * };
+ *
+ * SilcList list;
+ *
+ * // Initialize list
+ * silc_list_init(list, struct EntryStruct, next);
*
***/
#ifndef SILCLIST_H
#define SILCLIST_H
-/****s* silcutil/SilcList/SilcList
+/****s* silcutil/SilcList
*
* NAME
- *
+ *
* typedef struct { ... } SilcList;
*
* DESCRIPTION
* function silc_list_init.
*
***/
-typedef struct {
+typedef struct SilcListStruct {
void *head; /* Start of the list */
void *tail; /* End of the list */
void *current; /* Current pointer in list */
- unsigned int next_offset : 16; /* Offset to 'next' pointer */
- unsigned int prev_offset : 16; /* Offset to 'prev' pointer */
+ SilcUInt16 next_offset; /* Offset to 'next' pointer */
+ SilcUInt16 prev_offset; /* Offset to 'prev' pointer */
unsigned int prev_set : 1; /* Set if 'prev' exists */
unsigned int end_set : 1; /* Set if silc_list_end was called */
unsigned int count : 30; /* Number of entries in the list */
} SilcList;
-/****d* silcutil/SilcList/SILC_LIST_END
+/****d* silcutil/SILC_LIST_END
*
* NAME
- *
- * #define SILC_LIST_END ...
+ *
+ * #define SILC_LIST_END NULL
*
* DESCRIPTION
*
#define SILC_LIST_END NULL
/***/
-/****f* silcutil/SilcList/silc_list_init
+/****f* silcutil/silc_list_init
*
* SYNOPSIS
*
(list).next_offset = silc_offsetof(type, nextfield); \
(list).prev_set = 0; \
(list).prev_offset = 0; \
+ (list).end_set = 0; \
(list).head = (list).tail = (list).current = NULL; \
} while(0)
-/****f* silcutil/SilcList/silc_list_init_prev
+/****f* silcutil/silc_list_init_prev
*
* SYNOPSIS
*
(list).next_offset = silc_offsetof(type, nextfield); \
(list).prev_offset = silc_offsetof(type, prevfield); \
(list).prev_set = 1; \
+ (list).end_set = 0; \
(list).head = (list).tail = (list).current = NULL; \
} while(0)
-/****f* silcutil/SilcList/silc_list_count
+/****f* silcutil/silc_list_count
*
* SYNOPSIS
*
- * #define silc_list_count(list) ...
+ * SilcUInt32 silc_list_count(SilcList list);
*
* DESCRIPTION
*
***/
#define silc_list_count(list) (list).count
-/****f* silcutil/SilcList/silc_list_start
+/****f* silcutil/silc_list_start
*
* SYNOPSIS
*
- * #define silc_list_start(list) ...
+ * void silc_list_start(SilcList list);
*
* DESCRIPTION
*
#define silc_list_start(list) \
((list).current = (list).head, (list).end_set = 0)
-/****f* silcutil/SilcList/silc_list_end
+/****f* silcutil/silc_list_end
*
* SYNOPSIS
*
- * #define silc_list_end(list) ...
+ * void silc_list_end(SilcList list);
*
* DESCRIPTION
*
#define __silc_list_prev(list, pos) \
((void **)((unsigned char *)(pos) + (list).prev_offset))
-/****f* silcutil/SilcList/silc_list_add
+/****f* silcutil/silc_list_add
*
* SYNOPSIS
*
- * #define silc_list_add(list, entry) ...
+ * void silc_list_add(SilcList list, void *entry);
*
* DESCRIPTION
*
- * Adds new entry indicated by `entry' to the end of the list indicated
+ * Adds new entry indicated by `entry' to the end of the list indicated
* by `list'.
*
***/
(list).count++; \
} while(0)
-/****f* silcutil/SilcList/silc_list_del
+/****f* silcutil/silc_list_insert
+ *
+ * SYNOPSIS
+ *
+ * void silc_list_insert(SilcList list, void *current, void *entry);
+ *
+ * DESCRIPTION
+ *
+ * Insert new entry indicated by `entry' after the entry `current'
+ * to the list indicated by `list'. If `current' is NULL, then the
+ * `entry' is added at the head of the list. Use the silc_list_add
+ * to add at the end of the list.
+ *
+ ***/
+#define silc_list_insert(list, current, entry) \
+do { \
+ if (!(current)) { \
+ if ((list).head) \
+ *__silc_list_next(list, entry) = (list).head; \
+ else \
+ *__silc_list_next(list, entry) = NULL; \
+ if ((list).prev_set && (list).head) \
+ *__silc_list_prev(list, (list).head) = entry; \
+ if (!(list).tail) \
+ (list).tail = (entry); \
+ (list).head = (entry); \
+ if ((list).prev_set) \
+ *__silc_list_prev(list, entry) = NULL; \
+ } else { \
+ *__silc_list_next(list, entry) = *__silc_list_next(list, current); \
+ *__silc_list_next(list, current) = entry; \
+ if ((list).prev_set) { \
+ *__silc_list_prev(list, entry) = current; \
+ if (*__silc_list_next(list, entry)) \
+ *__silc_list_prev(list, *__silc_list_next(list, entry)) = entry; \
+ } \
+ if ((list).tail == (current)) \
+ (list).tail = (entry); \
+ } \
+ (list).count++; \
+} while(0)
+
+/****f* silcutil/silc_list_del
*
* SYNOPSIS
*
- * #define silc_list_del(list, entry) ...
+ * void silc_list_del(SilcListlist, void *entry);
*
* DESCRIPTION
*
for (p = &(list).head; *p; p = __silc_list_next(list, *p)) { \
if (*p == (entry)) { \
*p = *__silc_list_next(list, entry); \
- if (*p && (list).prev_set) \
+ if ((list).prev_set && *p) \
*__silc_list_prev(list, *p) = *__silc_list_prev(list, entry); \
if ((list).current == (entry)) \
(list).current = *p; \
(list).tail = prev; \
} while(0)
-/****f* silcutil/SilcList/silc_list_get
+/****f* silcutil/silc_list_get
*
* SYNOPSIS
*
- * #define silc_list_get(list) ...
+ * void *silc_list_get(SilcList list);
*
* DESCRIPTION
*
*
* EXAMPLE
*
- * // Traverse the list from the beginning to the end
+ * // Traverse the list from the beginning to the end
* silc_list_start(list);
* while ((entry = silc_list_get(list)) != SILC_LIST_END) {
* ...
return pos;
}
-#endif
+/****f* silcutil/silc_list_pop
+ *
+ * SYNOPSIS
+ *
+ * void *silc_list_pop(SilcList list);
+ *
+ * DESCRIPTION
+ *
+ * Pops the head of the list. Removes the head of the list and returns
+ * the removed head. This will always remove the head of the list even
+ * if silc_list_end was called. Calling silc_list_start is not necessary.
+ * Returns SILC_LIST_END if the list is empty.
+ *
+ ***/
+#define silc_list_pop(x) __silc_list_pop(&(x))
+static inline
+void *__silc_list_pop(SilcList *list)
+{
+ void *head, **p;
+
+ if (!list->head)
+ return NULL;
+
+ head = list->head;
+ p = &list->head;
+ *p = *__silc_list_next(*list, head);
+ if (list->prev_set && *p)
+ *__silc_list_prev(*list, *p) = *__silc_list_prev(*list, head);
+
+ if (list->current == head)
+ list->current = *p;
+ if (head == list->tail)
+ list->tail = NULL;
+
+ list->count--;
+
+ return head;
+}
+
+#endif /* SILCLIST_H */
projects / runtime.git / blobdiff