Added linked list implementation.

2 files changed, 176 insertions, 0 deletions

diff --git a/src/core/list.c b/src/core/list.c
new file mode 100644
index 00000000..f59c75e0
--- /dev/null
+++ b/src/core/list.c
@@ -0,0 +1,122 @@
+/*
+ * Copyright 2016 Garrett D'Amore <garrett@damore.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom
+ * the Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "core/nng_impl.h"
+
+/*
+ * Linked list implementation.  We implement a doubly linked list.
+ * Using pointer arithmetic, we can operate as a list of "anything".
+ */
+
+#define	NODE(list, item)	\
+	(nni_list_node_t)(void *)(((char *)item) + list->ll_offset)
+#define	ITEM(list, node)	\
+	(void *)(((char *)node) - list->ll_offset)
+
+void
+nni_list_init_offset(nni_list_t list, size_t offset)
+{
+	list->ll_offset = offset;
+	list->ll_head.ln_next = &list->ll_head;
+	list->ll_head.ln_prev = &list->ll_head;
+}
+
+void *
+nni_list_first(nni_list_t list)
+{
+	nni_list_node_t node = list->ll_head.ln_next;
+	if (node == &list->ll_head) {
+		return (NULL);
+	}
+	return (ITEM(list, node));
+}
+
+void *
+nni_list_last(nni_list_t list)
+{
+	nni_list_node_t node = list->ll_head.ln_prev;
+	if (node == &list->ll_head) {
+		return (NULL);
+	}
+	return (ITEM(list, node));
+}
+
+void
+nni_list_append(nni_list_t list, void *item)
+{
+	nni_list_node_t node = NODE(list, item);
+
+	node->ln_prev = list->ll_head.ln_prev;
+	node->ln_next = &list->ll_head;
+	node->ln_next->ln_prev = node;
+	node->ln_prev->ln_next = node;
+}
+void
+nni_list_prepend(nni_list_t list, void *item)
+{
+	nni_list_node_t node = NODE(list, item);
+
+	node->ln_next = list->ll_head.ln_next;
+	node->ln_prev = &list->ll_head;
+	node->ln_next->ln_prev = node;
+	node->ln_prev->ln_next = node;
+}
+
+void *
+nni_list_next(nni_list_t list, void *item)
+{
+	nni_list_node_t node = NODE(list, item);
+
+	if ((node = node->ln_next) == &list->ll_head) {
+		return (NULL);
+	}
+	return (ITEM(list, node));
+}
+
+void *
+nni_list_prev(nni_list_t list, void *item)
+{
+	nni_list_node_t node = NODE(list, item);
+
+	if ((node = node->ln_prev) == &list->ll_head) {
+		return (NULL);
+	}
+	return (ITEM(list, node));
+}
+
+void
+nni_list_remove(nni_list_t list, void *item)
+{
+	nni_list_node_t node = NODE(list, item);
+	node->ln_prev->ln_next = node->ln_next;
+	node->ln_next->ln_prev = node->ln_prev;
+}
+
+void
+nni_list_node_init(nni_list_t list, void *item)
+{
+	nni_list_node_t	node = NODE(list, item);
+	node->ln_prev = node->ln_next = NULL;
+}
diff --git a/src/core/list.h b/src/core/list.h
new file mode 100644
index 00000000..c55870cb
--- /dev/null
+++ b/src/core/list.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2016 Garrett D'Amore <garrett@damore.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom
+ * the Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef CORE_LIST_H
+#define CORE_LIST_H
+
+#include "core/nng_impl.h"
+
+/*
+ * In order to make life easy, we just define the list structures
+ * directly, and let consumers directly inline structures.
+ */
+typedef struct nni_list_node {
+	struct nni_list_node	*ln_next;
+	struct nni_list_node	*ln_prev;
+} *nni_list_node_t;
+
+typedef struct nni_list {
+	struct nni_list_node	ll_head;
+	size_t			ll_offset;
+} *nni_list_t;
+
+extern void nni_list_init_offset(nni_list_t list, size_t offset);
+#define	NNI_LIST_INIT(list, type, field)	\
+	nni_list_init_offset(list, type, (size_t)&((type *)0)->field)
+extern void *nni_list_first(nni_list_t list);
+extern void *nni_list_last(nni_list_t list);
+extern void nni_list_append(nni_list_t list, void *item);
+extern void nni_list_prepend(nni_list_t list, void *item);
+extern void *nni_list_next(nni_list_t list, void *item);
+extern void *nni_list_prev(nni_list_t list, void *item);
+extern void nni_list_remove(nni_list_t list, void *item);
+extern void nni_list_node_init(nni_list_t, void *);
+
+#endif	/* CORE_MSQUEUE_H */