test_malloc.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include <signal.h>
#define BYTE sizeof(int8_t)
#define KILOBYTE 1024*BYTE
#define MEGABYTE 1024*KILOBYTE
#define GIGABYTE 1024*MEGABYTE
#define DEFAULT_MALLOC_SIZE 1*GIGABYTE

int* int_array=0;

void sigintHandler(int signum){
    if (int_array){
        printf("free int_array");
        sleep(1);
        free(int_array);
    }
    exit(0);
}

int main(int argc, char* argv[]){
    char *endptr=NULL;
    int base=10;
    unsigned long malloc_size=DEFAULT_MALLOC_SIZE;
    int set_value=0;

    assert(argc <= 2);
    if (argc == 2){
        malloc_size=strtoul(argv[1], &endptr , base);
        //printf("%c\n", *endptr);
        //printf("%ld\n", malloc_size);
        switch (*endptr){
            case 'K':
                malloc_size=malloc_size*KILOBYTE;
                break;
            case 'M':
                malloc_size=malloc_size*MEGABYTE;
                break;
            case 'G':
                malloc_size=malloc_size*GIGABYTE;
                break;
            case 'k':
                malloc_size=malloc_size*KILOBYTE;
                break;
            case 'm':
                malloc_size=malloc_size*MEGABYTE;
                break;
            case 'g':
                malloc_size=malloc_size*GIGABYTE;
                break;
            default:
                break;
        }
    }
    int_array=(int * )malloc(malloc_size);
    memset(int_array, set_value, malloc_size);
    printf("%.3lf MB (%ld B) has been allocated\n", malloc_size/(1.0*MEGABYTE), malloc_size);
    signal(SIGINT, sigintHandler);
    while (1){
        set_value=rand();
        memset(int_array, set_value, malloc_size);
        printf("set %p to %d\n", int_array, set_value);
        sleep(10);
    }
    return 0;
}