Diff: singlylinkedlist.c

Revision:

13:920e00014ee3

Child:

19:2e0811512ceb

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/singlylinkedlist.c	Thu Oct 20 17:08:18 2016 -0700
@@ -0,0 +1,255 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+#include <stdlib.h>
+#ifdef _CRTDBG_MAP_ALLOC
+#include <crtdbg.h>
+#endif
+#include <stdbool.h>
+
+#include "azure_c_shared_utility/gballoc.h"
+#include "azure_c_shared_utility/singlylinkedlist.h"
+
+typedef struct LIST_ITEM_INSTANCE_TAG
+{
+    const void* item;
+    void* next;
+} LIST_ITEM_INSTANCE;
+
+typedef struct SINGLYLINKEDLIST_INSTANCE_TAG
+{
+    LIST_ITEM_INSTANCE* head;
+} LIST_INSTANCE;
+
+SINGLYLINKEDLIST_HANDLE singlylinkedlist_create(void)
+{
+    LIST_INSTANCE* result;
+
+    /* Codes_SRS_LIST_01_001: [singlylinkedlist_create shall create a new list and return a non-NULL handle on success.] */
+    result = (LIST_INSTANCE*)malloc(sizeof(LIST_INSTANCE));
+    if (result != NULL)
+    {
+        /* Codes_SRS_LIST_01_002: [If any error occurs during the list creation, singlylinkedlist_create shall return NULL.] */
+        result->head = NULL;
+    }
+
+    return result;
+}
+
+void singlylinkedlist_destroy(SINGLYLINKEDLIST_HANDLE list)
+{
+    /* Codes_SRS_LIST_01_004: [If the list argument is NULL, no freeing of resources shall occur.] */
+    if (list != NULL)
+    {
+        LIST_INSTANCE* list_instance = (LIST_INSTANCE*)list;
+
+        while (list_instance->head != NULL)
+        {
+            LIST_ITEM_INSTANCE* current_item = list_instance->head;
+            list_instance->head = (LIST_ITEM_INSTANCE*)current_item->next;
+            free(current_item);
+        }
+
+        /* Codes_SRS_LIST_01_003: [singlylinkedlist_destroy shall free all resources associated with the list identified by the handle argument.] */
+        free(list_instance);
+    }
+}
+
+LIST_ITEM_HANDLE singlylinkedlist_add(SINGLYLINKEDLIST_HANDLE list, const void* item)
+{
+    LIST_ITEM_INSTANCE* result;
+
+    /* Codes_SRS_LIST_01_006: [If any of the arguments is NULL, singlylinkedlist_add shall not add the item to the list and return NULL.] */
+    if ((list == NULL) ||
+        (item == NULL))
+    {
+        result = NULL;
+    }
+    else
+    {
+        LIST_INSTANCE* list_instance = (LIST_INSTANCE*)list;
+        result = (LIST_ITEM_INSTANCE*)malloc(sizeof(LIST_ITEM_INSTANCE));
+
+        if (result == NULL)
+        {
+            /* Codes_SRS_LIST_01_007: [If allocating the new list node fails, singlylinkedlist_add shall return NULL.] */
+            result = NULL;
+        }
+        else
+        {
+            /* Codes_SRS_LIST_01_005: [singlylinkedlist_add shall add one item to the tail of the list and on success it shall return a handle to the added item.] */
+            result->next = NULL;
+            result->item = item;
+
+            if (list_instance->head == NULL)
+            {
+                list_instance->head = result;
+            }
+            else
+            {
+                LIST_ITEM_INSTANCE* current = list_instance->head;
+                while (current->next != NULL)
+                {
+                    current = (LIST_ITEM_INSTANCE*)current->next;
+                }
+
+                current->next = result;
+            }
+        }
+    }
+
+    return result;
+}
+
+int singlylinkedlist_remove(SINGLYLINKEDLIST_HANDLE list, LIST_ITEM_HANDLE item)
+{
+    int result;
+
+	/* Codes_SRS_LIST_01_024: [If any of the arguments list or item_handle is NULL, singlylinkedlist_remove shall fail and return a non-zero value.] */
+	if ((list == NULL) ||
+        (item == NULL))
+    {
+        result = __LINE__;
+    }
+    else
+    {
+        LIST_INSTANCE* list_instance = (LIST_INSTANCE*)list;
+        LIST_ITEM_INSTANCE* current_item = list_instance->head;
+        LIST_ITEM_INSTANCE* previous_item = NULL;
+
+        while (current_item != NULL)
+        {
+            if (current_item == item)
+            {
+                if (previous_item != NULL)
+                {
+                    previous_item->next = current_item->next;
+                }
+                else
+                {
+                    list_instance->head = (LIST_ITEM_INSTANCE*)current_item->next;
+                }
+
+                free(current_item);
+
+                break;
+            }
+            previous_item = current_item;
+			current_item = (LIST_ITEM_INSTANCE*)current_item->next;
+        }
+
+		if (current_item == NULL)
+		{
+			/* Codes_SRS_LIST_01_025: [If the item item_handle is not found in the list, then singlylinkedlist_remove shall fail and return a non-zero value.] */
+			result = __LINE__;
+		}
+		else
+		{
+			/* Codes_SRS_LIST_01_023: [singlylinkedlist_remove shall remove a list item from the list and on success it shall return 0.] */
+			result = 0;
+		}
+    }
+
+    return result;
+}
+
+LIST_ITEM_HANDLE singlylinkedlist_get_head_item(SINGLYLINKEDLIST_HANDLE list)
+{
+    LIST_ITEM_HANDLE result;
+    
+    if (list == NULL)
+    {
+        /* Codes_SRS_LIST_01_009: [If the list argument is NULL, singlylinkedlist_get_head_item shall return NULL.] */
+        result = NULL;
+    }
+    else
+    {
+        LIST_INSTANCE* list_instance = (LIST_INSTANCE*)list;
+
+        /* Codes_SRS_LIST_01_008: [singlylinkedlist_get_head_item shall return the head of the list.] */
+        /* Codes_SRS_LIST_01_010: [If the list is empty, singlylinkedlist_get_head_item_shall_return NULL.] */
+        result = list_instance->head;
+    }
+
+    return result;
+}
+
+LIST_ITEM_HANDLE singlylinkedlist_get_next_item(LIST_ITEM_HANDLE item_handle)
+{
+    LIST_ITEM_HANDLE result;
+
+    if (item_handle == NULL)
+    {
+        /* Codes_SRS_LIST_01_019: [If item_handle is NULL then singlylinkedlist_get_next_item shall return NULL.] */
+        result = NULL;
+    }
+    else
+    {
+        /* Codes_SRS_LIST_01_018: [singlylinkedlist_get_next_item shall return the next item in the list following the item item_handle.] */
+        result = (LIST_ITEM_HANDLE)((LIST_ITEM_INSTANCE*)item_handle)->next;
+    }
+
+    return result;
+}
+
+const void* singlylinkedlist_item_get_value(LIST_ITEM_HANDLE item_handle)
+{
+    const void* result;
+
+    if (item_handle == NULL)
+    {
+        /* Codes_SRS_LIST_01_021: [If item_handle is NULL, singlylinkedlist_item_get_value shall return NULL.] */
+        result = NULL;
+    }
+    else
+    {
+        /* Codes_SRS_LIST_01_020: [singlylinkedlist_item_get_value shall return the value associated with the list item identified by the item_handle argument.] */
+        result = ((LIST_ITEM_INSTANCE*)item_handle)->item;
+    }
+
+    return result;
+}
+
+LIST_ITEM_HANDLE singlylinkedlist_find(SINGLYLINKEDLIST_HANDLE list, LIST_MATCH_FUNCTION match_function, const void* match_context)
+{
+    LIST_ITEM_HANDLE result;
+
+    if ((list == NULL) ||
+        (match_function == NULL))
+    {
+        /* Codes_SRS_LIST_01_012: [If the list or the match_function argument is NULL, singlylinkedlist_find shall return NULL.] */
+        result = NULL;
+    }
+    else
+    {
+        LIST_INSTANCE* list_instance = (LIST_INSTANCE*)list;
+        LIST_ITEM_INSTANCE* current = list_instance->head;
+
+        /* Codes_SRS_LIST_01_011: [singlylinkedlist_find shall iterate through all items in a list and return the first one that satisfies a certain match function.] */
+        while (current != NULL)
+        {
+            /* Codes_SRS_LIST_01_014: [list find shall determine whether an item satisfies the match criteria by invoking the match function for each item in the list until a matching item is found.] */
+            /* Codes_SRS_LIST_01_013: [The match_function shall get as arguments the list item being attempted to be matched and the match_context as is.] */
+            if (match_function((LIST_ITEM_HANDLE)current, match_context) == true)
+            {
+                /* Codes_SRS_LIST_01_017: [If the match function returns true, singlylinkedlist_find shall consider that item as matching.] */
+                break;
+            }
+
+            /* Codes_SRS_LIST_01_016: [If the match function returns false, singlylinkedlist_find shall consider that item as not matching.] */
+            current = (LIST_ITEM_INSTANCE*)current->next;
+        }
+
+        if (current == NULL)
+        {
+            /* Codes_SRS_LIST_01_015: [If the list is empty, singlylinkedlist_find shall return NULL.] */
+            result = NULL;
+        }
+        else
+        {
+            result = current;
+        }
+    }
+
+    return result;
+}