Easily find memory leaks, at runtime.

easy-leaks-finder.c

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

#ifndef HEAP_MAX
#define HEAP_MAX 50
#endif

struct HeapMap_s {
	void *memory;
	char *file;
	int line;
	size_t size;
} HeapMap[HEAP_MAX];

void __HeapLog__() {
	int i, count;
	
	for (i=0, count=0; i<HEAP_MAX; i++)
		if (HeapMap[i].memory != 0) {
			fprintf(stderr, "%lu bytes unallocated at %s:%i\n",
				HeapMap[i].size, HeapMap[i].file, HeapMap[i].line);
			
			count++;			
		}

	
	fprintf(stderr, "Total Leaks: %u\n\n", count);
}

void *__malloc__(size_t size, char *file, int line) {
	void *memory;
	int i;
	
	for (i=0; i<=HEAP_MAX; i++)
		if (HeapMap[i].memory == 0) break;
	
	if (i >= HEAP_MAX) {
		fprintf(stderr, "HEAP_MAX of %i bytes rechead!\n", HEAP_MAX);
		fprintf(stderr, "Try #define HEAP_MAX [bigger value]");
		exit(1);
	}
	
	memory = malloc(size);
	
	HeapMap[i].file = file;
	HeapMap[i].line = line;
	HeapMap[i].size = size;
	HeapMap[i].memory = memory;
	
	__HeapLog__();
	
	return memory;
}

void *__calloc__(size_t num, size_t size, char *file, int line) {
	void *memory;
	int i;
	
	for (i=0; i<=HEAP_MAX; i++)
		if (HeapMap[i].memory == 0) break;
	
	if (i >= HEAP_MAX) {
		fprintf(stderr, "HEAP_MAX of %i bytes rechead!\n", HEAP_MAX);
		fprintf(stderr, "Try #define HEAP_MAX [bigger value]");
		exit(1);
	}
	
	memory = calloc(num, size);
	
	HeapMap[i].file = file;
	HeapMap[i].line = line;
	HeapMap[i].size = size;
	HeapMap[i].memory = memory;
	
	__HeapLog__();
	
	return memory;
}

void __free__(void *memory) {
	int i;
	
	for (i=0; i<=HEAP_MAX; i++)
		if (HeapMap[i].memory == memory) {
		    HeapMap[i].memory = 0;
		    break;
		}
		
	if (i >= HEAP_MAX) return;
	
	free(memory);
	
	__HeapLog__();
}

#define malloc(size) __malloc__(size, __FILE__, __LINE__)
#define calloc(num, size) __calloc__(num, size, __FILE__, __LINE__)
#define free(memory) {__free__(memory); memory = 0;}

/*///////////////////////////////////
	
          	Testing:
		
///////////////////////////////////*/

int main() {
	
	char* a = malloc(sizeof(char) * 2048);
	a = malloc(sizeof(char) * 1024);
	free(a);
}