updated list lib

list_removers.c

@@ -0,0 +1,81 @@
+#include <list.h>
+#include <stdlib.h>
+
+int ListRemove(LIST *list) {
+  NODE *unused;
+  if (list->current == NULL) {
+    return -1;
+  }
+  if (list->size == 1) {
+    unused = list->current;
+    list->current = NULL;
+    list->head = NULL;
+    list->tail = NULL;
+  }
+  else if (list->current == list->head) {
+    unused = list->head;
+    list->head = list->head->next;
+    list->current = list->head;
+    list->current->previous = NULL;
+  }
+  else if (list->current == list->tail) {
+    unused = list->tail;
+    list->tail= list->tail->previous;
+    list->current = list->tail;
+    list->current->next = NULL;
+  }
+  else {
+    unused = list->current;
+    list->current->previous->next = list->current->next;
+    list->current->next->previous = list->current->previous;
+    list->current = list->current->next;
+  }
+
+  unused->data = NULL;
+  free(unused->data);
+  unused->next = NULL;
+  unused->previous = NULL;
+  unused = NULL;
+  free(unused);
+  list->size--;
+  return 0;
+
+}
+
+void ListFree(LIST *list) {
+  ListFirst(list);
+  while (list->head != NULL) {
+    ListRemove(list);
+  }
+  free(list);
+
+}
+
+void *ListTrim(LIST *list) {
+  NODE *tempnode = list->tail->previous;
+  list->tail->previous = NULL;
+  free(list->tail);
+  list->tail = tempnode;
+  list->size--;
+  return 0;
+}
+
+void *ListSearch(LIST *list, int (*comparator)(void *, void*), 
+    void *comparisonArg) {
+  ListFirst(list);
+  while (list->current != NULL) {
+    if ((*comparator)(list->current->data, comparisonArg)) {
+      break;
+    }
+    else {
+      ListNext(list);
+    }
+  }
+
+  if (list->current == NULL) {
+    list->current = list->tail;
+    return NULL;
+  }
+  
+  return list->current;
+}