#include <ctype.h>

#include <sys/wait.h>

#include "util.h"

#include "log.h"

#include "sd-bus.h"

#include "bus-message.h"

#include "bus-error.h"

#include "bus-kernel.h"

#include "bus-internal.h"

#define N_TRIES 500

#define MAX_SIZE (5*1024*1024)

static void server(sd_bus *b, usec_t *result) {

usec_t x = 0;

int r;

for (;;) {

_cleanup_bus_message_unref_ sd_bus_message *m = NULL;

r = sd_bus_process(b, &m);

assert_se(r >= 0);

if (r == 0)

assert_se(sd_bus_wait(b, (usec_t) -1) >= 0);

if (!m)

continue;

/* log_error("huhu %s from %s", sd_bus_message_get_member(m), sd_bus_message_get_sender(m)); */

if (sd_bus_message_is_method_call(m, "benchmark.server", "Work")) {

_cleanup_bus_message_unref_ sd_bus_message *reply = NULL;

size_t i, sz;

char *q;

const char *p;

assert_se(sd_bus_message_read_array(m, 'y', (const void**) &p, &sz) > 0);

assert_se(sd_bus_message_new_method_return(b, m, &reply) >= 0);

assert_se(sd_bus_message_append_array_space(reply, 'y', sz, (void**) &q) >= 0);

x = now(CLOCK_MONOTONIC);

for (i = 0; i < sz; i++)

q[i] = toupper(p[i]);

x = now(CLOCK_MONOTONIC) - x;

assert_se(sd_bus_send(b, reply, NULL) >= 0);

} else if (sd_bus_message_is_method_call(m, "benchmark.server", "Exit")) {

usec_t t;

assert_se(sd_bus_message_read(m, "t", &t) > 0);

assert_se(t >= x);

*result = t - x;

return;

} else if (sd_bus_message_is_method_call(m, "benchmark.server", "Ping")) {

assert_se(sd_bus_reply_method_return(b, m, "y", 1) >= 0);

} else

assert_not_reached("Unknown method");

}

}

static void client(sd_bus *b, size_t sz) {

_cleanup_bus_message_unref_ sd_bus_message *m = NULL, *reply = NULL;

char *p;

const char *q;

usec_t t;

size_t l, i;

assert_se(sd_bus_call_method(b, ":1.1", "/", "benchmark.server", "Ping", NULL, NULL, NULL) >= 0);

assert_se(sd_bus_message_new_method_call(b, ":1.1", "/", "benchmark.server", "Work", &m) >= 0);

assert_se(sd_bus_message_append_array_space(m, 'y', sz, (void**) &p) >= 0);

for (i = 0; i < sz; i++)

p[i] = 'a' + (char) (i % 26);

t = now(CLOCK_MONOTONIC);

assert_se(sd_bus_send_with_reply_and_block(b, m, 0, NULL, &reply) >= 0);

t = now(CLOCK_MONOTONIC) - t;

assert_se(sd_bus_message_read_array(reply, 'y', (const void**) &q, &l) > 0);

assert_se(l == sz);

for (i = 0; i < sz; i++) {

assert_se(q[i] == 'A' + (char) (i % 26));

}

sd_bus_message_unref(m);

assert_se(sd_bus_message_new_method_call(b, ":1.1", "/", "benchmark.server", "Exit", &m) >= 0);

assert_se(sd_bus_message_append(m, "t", t) >= 0);

assert_se(sd_bus_send(b, m, NULL) >= 0);

}

static void run_benchmark(size_t sz, bool force_copy, usec_t *result) {

_cleanup_close_ int bus_ref = -1;

_cleanup_free_ char *bus_name = NULL, *address = NULL;

sd_bus *b;

int r;

pid_t pid;

bus_ref = bus_kernel_create("deine-mutter", &bus_name);

if (bus_ref == -ENOENT)

exit(EXIT_TEST_SKIP);

assert_se(bus_ref >= 0);

address = strappend("kernel:path=", bus_name);

assert_se(address);

r = sd_bus_new(&b);

assert_se(r >= 0);

b->use_memfd = force_copy ? 0 : -1;

r = sd_bus_set_address(b, address);

assert_se(r >= 0);

r = sd_bus_start(b);

assert_se(r >= 0);

pid = fork();

assert_se(pid >= 0);

if (pid == 0) {

close_nointr_nofail(bus_ref);

sd_bus_unref(b);

r = sd_bus_new(&b);

assert_se(r >= 0);

b->use_memfd = force_copy ? 0 : -1;

r = sd_bus_set_address(b, address);

assert_se(r >= 0);

r = sd_bus_start(b);

assert_se(r >= 0);

client(b, sz);

_exit(0);

}

server(b, result);

sd_bus_unref(b);

assert_se(waitpid(pid, NULL, 0) == pid);

}

int main(int argc, char *argv[]) {

size_t lsize, rsize, csize;

log_set_max_level(LOG_DEBUG);

lsize = 1;

rsize = MAX_SIZE;

for (;;) {

usec_t copy = 0, memfd = 0;

unsigned i;

csize = (lsize + rsize) / 2;

log_info("Trying size=%zu", csize);

if (csize <= lsize)

break;

for (i = 0; i < N_TRIES; i++) {

usec_t t;

run_benchmark(csize, true, &t);

copy += t;

}

for (i = 0; i < N_TRIES; i++) {

usec_t t;

run_benchmark(csize, false, &t);

memfd += t;

}

copy /= N_TRIES;

memfd /= N_TRIES;

if (copy == memfd)

break;

if (copy < memfd)

lsize = csize;

else

rsize = csize;

}

log_info("Copying/memfd are equally fast at %zu", csize);

return 0;

}