Simplified and fixed the swap function, also fixed the bubble sort code.

sorting_algorithms/bubble_sort/bubble_sort.c

@@ -22,29 +22,20 @@ void* bubble_sort(void* array, int (*comparison_function)(const void*, const voi
 
 	/* Local variables. */
 	int i, j;
-	void *tmp;
-
-	/* Allocate the buffer. */
-	tmp = (void*) malloc(size);
-	if (tmp == NULL)
-		return NULL;
 
 	/* Sort according to array, and comparison function. */
 	for (i = 0; i < length; i++)
 		for (j = 0; j < length - 1; j++) {
 			/* Check if to swap. */
-			if (!comparison_function(array + j, array + j + 1)) {
+			if (!comparison_function(array + (j * size), array + ((j + 1) * size))) {
 				/* Swap. */
-				swap_void_ptr((array + j), (array + j + 1), tmp, size);
-				/* tmp = array[j];
-				* array[j] = array[j + 1];
-				* array[j + 1] = tmp; */
+				swap_void_ptr(array + (j * size), array + ((j + 1) * size), size);
+				/*tmp = array[j];
+				array[j] = array[j + 1];
+				array[j + 1] = tmp;*/
 			}
 		}
 
-	/* Free the buffer. */
-	free(tmp);
-
 	/* Return the result. */
 	return array;
 }

utils/swap_void.c

@@ -1,14 +1,15 @@
 /* Function to swap void* objects. */
-#include <stdlib.h>
 #include "swap_void.h"
 
 /* This function swaps void* objects. */
-/* Temp should be an allocated buffer, used to do the swap. */
 /* Size should be > 0. */
 /* Expect undefined behavior if conditions aren't met. */
-extern inline void swap_void_ptr(void *first, void *second, void *temp, size_t size) {
+extern inline void swap_void_ptr(void *first, void *second, size_t size) {
 	/* Swap. */
-	memcpy(temp, first, size);
-	memcpy(first, second, size);
-	memcpy(second, temp, size);
+	char *a = (char*)first, *b = (char*)second, c;
+	while(size--) {
+		c = a[size];
+		a[size] = b[size];
+		b[size] = c;
+	}
 }

utils/swap_void.h

@@ -4,6 +4,6 @@
 #include <string.h>
 
 /* This function is used to swap void* objects. */
-extern inline void swap_void_ptr(void *first, void *second, void *temp, size_t size);
+extern inline void swap_void_ptr(void *first, void *second, size_t size);
 
 #endif //SWAP_VOID_H