allocbot

allocbot.c

/**
 * allocbot.c - mindlessly allocate memory
 *
 * Florian Dejonckheere <[email protected]
 *
 * */

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

#define ALLOC (10 * 1024 * 1024)

void main() {
	while(1) {
		// Allocate 10 MiB
		void *ptr = malloc(ALLOC);
		bzero(ptr, ALLOC);
		printf("Allocated 10 MiB\n");
		usleep(100000);
	}
}

allocbot2.c

/**
 * allocbot2.c - allocate or deallocate memory on demand
 *
 * Florian Dejonckheere <[email protected]
 *
 * Usage: press '+' or '-' and enter to enter allocating
 * or deallocating mode. Press enter to execute action.
 *
 * */

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <signal.h>

// 10 MiB
#define ALLOC (10 * 1024 * 1024)

// Mode: 0 = allocate, 1 = free
int mode = 0;

// Stack
typedef struct Stack {
	void *mem;
	struct Stack *next;
} Stack;

unsigned long total = 0;

Stack *stack = NULL;

struct termios new_kbd_mode;
struct termios g_old_kbd_mode;

char* readable_fs(double size/*in bytes*/, char *buf) {
	int i = 0;
	const char* units[] = {"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB"};
	while(size > 1024) {
		size /= 1024;
		i++;
	}
	sprintf(buf, "%.*f %s", i, size, units[i]);
	return buf;
}

void cleanup() {
	while(stack != NULL) {
		Stack *next = stack->next;
		free(stack->mem);
		free(stack);
		stack = next;
	}

	char buf[10];
	printf("De-allocated %s, exiting...\n", readable_fs((total * ALLOC), buf));

	// Put keyboard back in old mode
	tcsetattr (0, TCSANOW, &g_old_kbd_mode);

	exit(0);
}

void main() {
	signal(SIGINT, cleanup);

	// Put keyboard (stdin) in raw, unbuffered mode
	tcgetattr (0, &g_old_kbd_mode);
	memcpy (&new_kbd_mode, &g_old_kbd_mode, sizeof (struct termios));

	new_kbd_mode.c_lflag &= ~(ICANON | ECHO);
	new_kbd_mode.c_cc[VTIME] = 0;
	new_kbd_mode.c_cc[VMIN] = 1;
	tcsetattr (0, TCSANOW, &new_kbd_mode);

	char c;
	while(c = getchar()) {
		if(c == '+') {
			mode = 0;
			printf("Entering allocation mode\n");
		} else if(c == '-') {
			mode = 1;
			printf("Entering de-allocation mode\n");
		} else if(c == '\n') {
			if(mode) {
				// De-allocate
				if(stack != NULL) {
					Stack *next = stack->next;
					free(stack->mem);
					free(stack);
					stack = next;
					total--;
					char buf[10];
					printf("De-allocated %d bytes, %s total\n", ALLOC, readable_fs((total * ALLOC), buf));
				} else printf("Nothing to deallocate\n");
			} else {
				// Allocate
				Stack *top = malloc(sizeof(Stack));
				top->mem = malloc(ALLOC);
				bzero(top->mem, ALLOC);
				top->next = stack;
				stack = top;
				total++;
				char buf[10];
				printf("Allocated %d bytes, %s total\n", ALLOC, readable_fs((total * ALLOC), buf));
			}
		}
	}

	// Put keyboard back in old mode
	tcsetattr (0, TCSANOW, &g_old_kbd_mode);

	exit(0);
}