valgrind_test.c

#include <stdlib.h>
#include <stdio.h>

struct list_node {
	int val;
	struct list_node* next;
};

typedef struct list_node node_t;

typedef struct {
	node_t* root;
} list_t;

node_t*
list_insert_impl(node_t* root, int val);
node_t*
list_remove_impl(node_t* root, int val);

list_t*
new_list() {
	list_t* l = (list_t*)malloc(sizeof(list_t));
	return l;
}

void
list_insert(list_t* list, int val) {
	list->root = list_insert_impl(list->root, val);
}

void
list_remove(list_t* list, int val) {
	list->root = list_remove_impl(list->root, val);
}

void
list_destroy(list_t* list) {
	while(list->root) {
		list_remove(list, list->root->val);
	}

	free(list);
}

node_t*
list_create_node(int val) {
	node_t* n = (node_t*)malloc(sizeof(node_t));
	n->val = val;
	return n;
}

node_t*
list_insert_impl(node_t* root, int val) {
	if(root == NULL) {
		return list_create_node(val);
	}

	if(val < root->val) {
		node_t* n = list_create_node(val);
		n->next = root;
		return n;
	}

	root->next = list_insert_impl(root->next, val);
	return root;
}

node_t*
list_remove_impl(node_t* root, int val) {
	if(root == NULL) {
		return NULL;
	}

	if(root->val == val) {
		node_t* next = root->next;
		free(root);
		return next;
	}

	root->next = list_remove_impl(root->next, val);
	return root;
}

void
main() {
	node_t* curr;
	int i;

	list_t* l = new_list();

	list_insert(l, 0);
	list_insert(l, 5);
	list_insert(l, 3);
	list_insert(l, 9);
	list_insert(l, -5);

	curr = l->root;

	while(curr) {
		printf("%d\n", curr->val);
		curr = curr->next ;
	}

	list_remove(l, 3);
	list_remove(l, 2);

	curr = l->root;

	printf("-----\n");

	while(curr) {
		printf("%d\n", curr->val);
		curr = curr->next ;
	}

	list_destroy(l);
}

/* Valgrind output:
==28499== 
==28499== HEAP SUMMARY:
==28499==     in use at exit: 0 bytes in 0 blocks
==28499==   total heap usage: 6 allocs, 6 frees, 88 bytes allocated
==28499== 
==28499== All heap blocks were freed -- no leaks are possible
==28499== 
==28499== For counts of detected and suppressed errors, rerun with: -v
==28499== Use --track-origins=yes to see where uninitialised values come from
==28499== ERROR SUMMARY: 5 errors from 5 contexts (suppressed: 2 from 2)
*/