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/*
* Copyright (C) 2006-2012 FAUmachine Team <info@faumachine.org>.
* This program is free software. You can redistribute it and/or modify it
* under the terms of the GNU General Public License, either version 2 of
* the License, or (at your option) any later version. See COPYING.
*/
#include <sys/mman.h>
#include <assert.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
extern char _end;
enum type { END, HEAP, MMAP, LIB, STACK, COUNT };
static void
test(void)
{
int var;
enum type t;
for (t = 0; t < COUNT; t++) {
switch (t) {
case END:
printf("(%p)\n", &_end);
break;
case HEAP:
printf("(%p)\n", malloc(1));
break;
case MMAP:
printf("(%p)\n", mmap(NULL, 4096, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS,
-1, 0));
break;
case STACK:
printf("(%p)\n", &var);
break;
default:
break;
}
}
}
static uintptr_t
valread(FILE *fp)
{
char line[1024];
if (! fgets(line, sizeof(line) - 1, fp)) {
return -1;
}
line[sizeof(line) - 1] = '\0';
assert(strchr(line, '('));
return strtoul(strchr(line, '(') + 1, NULL, 0);
}
static void
eval(void)
{
const char *name[COUNT] = {
[END] = "end",
[HEAP] = "heap",
[MMAP] = "mmap",
[LIB] = "lib",
[STACK] = "stack",
[LIB] = "lib",
};
uintptr_t min[COUNT], max[COUNT];
uintptr_t gap[COUNT];
unsigned int count;
enum type t;
for (t = 0; t < COUNT; t++) {
min[t] = -1; max[t] = 0;
}
for (count = 0; count < 10000; count++) {
FILE *fp;
uintptr_t curr;
/* Get addresses of end/heap/mmap/stack. */
fp = popen("./vm-test -s", "r");
assert(fp);
for (t = 0; t < COUNT; t++) {
if (t == LIB) continue;
curr = valread(fp);
if (curr < min[t]) min[t] = curr;
if (max[t] < curr) max[t] = curr;
}
pclose(fp);
/* Get addresses of mapped libraries. */
fp = popen("ldd ./vm-test", "r");
for (;;) {
curr = valread(fp);
if (curr == (uintptr_t) -1) {
break;
}
if (curr < min[LIB]) min[LIB] = curr;
if (max[LIB] < curr) max[LIB] = curr;
}
pclose(fp);
}
for (t = 0; t < COUNT; t++) {
uintptr_t next;
enum type t2;
next = max[STACK];
for (t2 = 0; t2 < COUNT; t2++) {
if (t2 == t) continue;
if (min[t] <= min[t2]
&& min[t2] <= max[t]) {
/* Regions overlap. */
next = max[t];
} else if (max[t] < min[t2]
&& min[t2] < next) {
next = min[t2];
}
}
gap[t] = next - max[t];
}
for (t = 0; t < COUNT; t++) {
printf("0x%lx <= %s <= 0x%lx (gap 0x%lx)\n",
(unsigned long) min[t],
name[t],
(unsigned long) max[t],
(unsigned long) gap[t]);
}
}
int
main(int argc, char **argv)
{
if (1 < argc) {
test();
} else {
eval();
}
return 0;
}
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