From: Art Cancro <ajc@citadel.org>
Date: Fri, 11 Nov 2022 23:45:41 +0000 (-0500)
Subject: array_delete_element_at() now uses memmove() instead of memcpy() because it is suppos... 
X-Git-Tag: v959~1
X-Git-Url: https://code.citadel.org/?p=citadel.git;a=commitdiff_plain;h=105801284b462764dd8059e543475c68335da642

array_delete_element_at() now uses memmove() instead of memcpy() because it is supposed to be safer.
---

diff --git a/libcitadel/lib/array.c b/libcitadel/lib/array.c
index daed5a3aa..b30e9ebf2 100644
--- a/libcitadel/lib/array.c
+++ b/libcitadel/lib/array.c
@@ -1,13 +1,11 @@
-/*
- * This is a quickly-hacked-together implementation of an elastic array class.  It includes constructor and destructor
- * methods, append and access methods, and that's about it.  The memory allocation is very naive: whenever we are about
- * to append beyond the size of the buffer, we double its size.
- *
- * Copyright (c) 2021 by Art Cancro
- *
- * This program is open source software.  Use, duplication, or disclosure
- * is subject to the terms of the GNU General Public License, version 3.
- */
+// This is a simple implementation of an elastic array class.  It includes constructor and destructor
+// methods, append and access methods, and that's about it.  The memory allocation is very naive: whenever
+// we are about to append beyond the size of the buffer, we double its size.
+//
+// Copyright (c) 2021-2022 by Art Cancro
+//
+// This program is open source software.  Use, duplication, or disclosure
+// is subject to the terms of the GNU General Public License, version 3.
 
 
 #include <stdlib.h>
@@ -15,9 +13,7 @@
 #include <stdio.h>
 #include "libcitadel.h"
 
-/*
- * Constructor for elastic array
- */
+// Constructor for elastic array
 Array *array_new(size_t element_size) {
 	Array *newarr = malloc(sizeof(Array));
 	if (newarr) {
@@ -28,18 +24,14 @@ Array *array_new(size_t element_size) {
 }
 
 
-/*
- * Destructor for elastic array
- */
+// Destructor for elastic array
 void array_free(Array *arr) {
 	free(arr->the_elements);
 	free(arr);
 }
 
 
-/*
- * Append an element to an array (we already know the element size because it's in the data type)
- */
+// Append an element to an array (we already know the element size because it's in the data type)
 void array_append(Array *arr, void *new_element) {
 
 	if (!arr) {						// silently fail if they gave us a null array
@@ -68,34 +60,26 @@ void array_append(Array *arr, void *new_element) {
 }
 
 
-/*
- * Return the element in an array at the specified index
- */
+// Return the element in an array at the specified index
 void *array_get_element_at(Array *arr, int index) {
 	return (arr->the_elements + ( index * arr->element_size ));
 }
 
 
-/*
- * Return the number of elements in an array
- */
+// Return the number of elements in an array
 int array_len(Array *arr) {
 	return arr->num_elements;
 }
 
 
-/*
- * Sort an array.  We already know the element size and number of elements, so all we need is
- * a sort function, which we will pass along to qsort().
- */
+// Sort an array.  We already know the element size and number of elements, so all we need is
+// a sort function, which we will pass along to qsort().
 void array_sort(Array *arr, int (*compar)(const void *, const void *)) {
 	qsort(arr->the_elements, arr->num_elements, arr->element_size, compar);
 }
 
 
-/*
- * Delete an element from an array
- */
+// Delete an element from an array
 void array_delete_element_at(Array *arr, int index) {
 
 	if (index >= arr->num_elements) {		// If the supplied index is out of bounds, return quietly.
@@ -112,7 +96,7 @@ void array_delete_element_at(Array *arr, int index) {
 		return;
 	}
 
-	memcpy(
+	memmove(					// memmove() is supposed to be safer than memcpy()
 		(arr->the_elements + (index * arr->element_size)),
 		arr->the_elements + ((index+1) * arr->element_size),
 		(arr->num_elements - index) * arr->element_size