- Added generic list library.

src/list.c

@@ -0,0 +1,243 @@
+/**
+ *@file list.c
+ * Generic list type
+ *
+ * A doubly linked list with void* as data type.
+ */
+
+#include "list.h"
+#include <malloc.h>
+
+//! Make a node
+List
+list_create (const void *data)
+{
+  List newlist;
+
+  newlist = (List) malloc (sizeof (struct list_struct));
+  newlist->prev = NULL;
+  newlist->next = NULL;
+  newlist->data = (void *) data;
+  return newlist;
+}
+
+//! Rewind list
+List
+list_rewind (List list)
+{
+  if (list != NULL)
+    {
+      while (list->prev != NULL)
+	{
+	  list = list->prev;
+	}
+    }
+  return list;
+}
+
+//! Forward list
+List
+list_forward (List  list)
+{
+  if (list == NULL)
+    {
+      return NULL;
+    }
+  else
+    {
+      while (list->next != NULL)
+	{
+	  list = list->next;
+	}
+      return list;
+    }
+}
+
+//! Add element to list, inserting it just before the current node.
+/**
+ * @returns the head of the list
+ */
+List
+list_insert (List list, const void *data)
+{
+  List newnode;
+
+  newnode = list_create (data);
+  if (list == NULL)
+    {
+      return newnode;
+    }
+  newnode->next = list;
+  newnode->prev = list->prev;
+  list->prev = newnode;
+  if (newnode->prev != NULL)
+    {
+      newnode->prev->next = newnode;
+      return list_rewind (newnode->prev);
+    }
+  else
+    {
+      return newnode;
+    }
+}
+
+//! Add element to list, inserting it just after the current node.
+/**
+ * @returns the head of the list
+ */
+List
+list_add (List list, const void *data)
+{
+  List newnode;
+
+  newnode = list_create (data);
+  if (list == NULL)
+    {
+      return newnode;
+    }
+  else
+    {
+      newnode->next = list->next;
+      newnode->prev = list;
+      list->next = newnode;
+      if (newnode->next != NULL)
+	{
+	  newnode->next->prev = newnode;
+	}
+      return list_rewind (list);
+    }
+}
+
+//! Add element to list, inserting it at the tail of the list.
+/**
+ * @returns the head of the list
+ */
+List
+list_append (List list, const void *data)
+{
+  List newnode;
+  List lastnode;
+
+  newnode = list_create (data);
+  if (list == NULL)
+    {
+      return newnode;
+    }
+  else
+    {
+      lastnode = list_forward (list);
+      newnode->prev = lastnode;
+      lastnode->next = newnode;
+      return list_rewind (list);
+    }
+}
+
+
+//! Destroy a node
+/**
+ * @returns the head of the list
+ */
+List
+list_delete (List list)
+{
+  if (list != NULL)
+    {
+      List prenode, postnode;
+
+      prenode = list->prev;
+      postnode = list->next;
+      free (list);
+      if (postnode != NULL)
+	{
+	  postnode->prev = prenode;
+	}
+      if (prenode != NULL)
+	{
+	  prenode->next = postnode;
+	  return list_rewind (prenode);
+	}
+      else
+	{
+	  return postnode;
+	}
+    }
+  else
+    {
+      return NULL;
+    }
+}
+
+//! Test if it's already in the list, using pointer equality.
+/**
+ *@warn Only scans forward, so make sure the list is rewound.
+ *@returns The boolean result.
+ */
+int
+in_list (List list, const void *compdata)
+{
+  while (list != NULL)
+    {
+      if (list->data == compdata)
+	{
+	  return 1;
+	}
+      list = list->next;
+    }
+  return 0;
+}
+
+//! Iterator
+/**
+ * Function used returns int; if non-zero (true), iteration continues.
+ * Function is called with data as argument, *not* the list node.
+ *
+ *@returns true iff domain empty or all applications true. If false, some iteration aborted the run.
+ */
+int
+list_iterate (List list, int (*func) ())
+{
+  while (list != NULL)
+    {
+      if (!func (list->data))
+	{
+	  return 0;
+	}
+      list = list->next;
+    }
+  return 1;
+}
+
+//! Duplicate (always shallow)
+List
+list_duplicate (List list)
+{
+  List newlist;
+
+  if (list == NULL)
+    {
+      return NULL;
+    }
+  list = list_forward (list);
+  newlist = NULL;
+  while (list != NULL)
+    {
+      newlist = list_insert (newlist, list->data);
+      list = list->prev;
+    }
+  return newlist;
+}
+
+//! Destroy (shallow)
+void
+list_destroy (List list)
+{
+  list = list_rewind (list);
+  while (list != NULL)
+    {
+      List node;
+
+      node = list;
+      list = list->next;
+      free (node);
+    }
+}

src/list.h

@@ -0,0 +1,25 @@
+#ifndef GENERICLIST
+#define GENERICLIST
+
+struct list_struct
+{
+  struct list_struct *next;
+  struct list_struct *prev;
+  void *data;
+};
+
+typedef struct list_struct *List;
+
+List list_create (const void *data);
+List list_rewind (List list);
+List list_forward (List  list);
+List list_insert (List list, const void *data);
+List list_add (List list, const void *data);
+List list_append (List list, const void *data);
+List list_delete (List list);
+int in_list (List list, const void *data);
+int list_iterate (List list, int (*func) ());
+List list_duplicate (List list);
+void list_destroy (List list);
+
+#endif