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#include <errno.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <emscripten.h>
#include <stdio.h>
class random_device
{
int __f_;
public:
// constructors
explicit random_device();
~random_device();
// generating functions
unsigned operator()();
};
random_device::random_device()
{
__f_ = open("/dev/urandom", O_RDONLY);
if (__f_ < 0) abort();
}
random_device::~random_device()
{
close(__f_);
}
unsigned
random_device::operator()()
{
unsigned r;
size_t n = sizeof(r);
char* p = reinterpret_cast<char*>(&r);
while (n > 0)
{
ssize_t s = read(__f_, p, 1);
if (s == 0) abort();
if (s == -1)
{
if (errno != EINTR) abort();
continue;
}
n -= static_cast<size_t>(s);
p += static_cast<size_t>(s);
}
return r;
}
int main() {
int total = 0;
for (int i = 0; i < ITERATIONS; i++) {
// printf causes proxying
printf("%d %d\n", i, total);
for (int j = 0; j < 1024; j++) {
// allocation uses a mutex
auto* rd = new random_device();
// reading data causes proxying
for (int k = 0; k < 4; k++) {
total += (*rd)();
}
// make sure the optimizer doesn't remove the allocation
EM_ASM({ out("iter") }, rd);
delete rd;
}
}
printf("done: %d", total);
return 0;
}
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