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#define TEST_MACROS
#include "tests.h"
#include <camellia/flags.h>
#include <camellia/syscalls.h>
#include <string.h>
#include <unistd.h>
static const char *pipe_msgs[2] = {"hello", "world"};
void test_pipe(void) {
handle_t ends[2];
char buf[16];
int ret;
/* test regular reads / writes */
assert(_syscall_pipe(ends, 0) >= 0);
if (!fork()) {
/* those repeated asserts ensure that you can't read/write to the wrong ends */
assert(_syscall_read(ends[1], buf, 16, 0) < 0);
assert(_syscall_write(ends[0], buf, 16, 0, 0) < 0);
ret = _syscall_write(ends[1], pipe_msgs[0], 5, -1, 0);
assert(ret == 5);
assert(_syscall_read(ends[1], buf, 16, 0) < 0);
assert(_syscall_write(ends[0], buf, 16, 0, 0) < 0);
ret = _syscall_write(ends[1], pipe_msgs[1], 5, -1, 0);
assert(ret == 5);
exit(0);
} else {
assert(_syscall_read(ends[1], buf, 16, 0) < 0);
assert(_syscall_write(ends[0], buf, 16, 0, 0) < 0);
ret = _syscall_read(ends[0], buf, 16, 0);
assert(ret == 5);
assert(!memcmp(buf, pipe_msgs[0], 5));
assert(_syscall_read(ends[1], buf, 16, 0) < 0);
assert(_syscall_write(ends[0], buf, 16, 0, 0) < 0);
_syscall_read(ends[0], buf, 16, 0);
assert(ret == 5);
assert(!memcmp(buf, pipe_msgs[1], 5));
_syscall_await();
}
close(ends[0]);
close(ends[1]);
/* writing to pipes with one end closed */
assert(_syscall_pipe(ends, 0) >= 0);
for (int i = 0; i < 16; i++) {
if (!fork()) {
close(ends[1]);
assert(_syscall_read(ends[0], buf, 16, 0) < 0);
exit(0);
}
}
close(ends[1]);
for (int i = 0; i < 16; i++)
_syscall_await();
close(ends[0]);
assert(_syscall_pipe(ends, 0) >= 0);
for (int i = 0; i < 16; i++) {
if (!fork()) {
close(ends[0]);
assert(_syscall_write(ends[1], buf, 16, 0, 0) < 0);
exit(0);
}
}
close(ends[0]);
for (int i = 0; i < 16; i++)
_syscall_await();
close(ends[1]);
/* queueing */
assert(_syscall_pipe(ends, 0) >= 0);
for (int i = 0; i < 16; i++) {
if (!fork()) {
assert(_syscall_write(ends[1], pipe_msgs[0], 5, -1, 0) == 5);
exit(0);
}
}
close(ends[1]);
for (int i = 0; i < 16; i++) {
assert(_syscall_read(ends[0], buf, sizeof buf, 0) == 5);
_syscall_await();
}
assert(_syscall_read(ends[0], buf, sizeof buf, 0) < 0);
close(ends[0]);
assert(_syscall_pipe(ends, 0) >= 0);
for (int i = 0; i < 16; i++) {
if (!fork()) {
memset(buf, 0, sizeof buf);
assert(_syscall_read(ends[0], buf, 5, -1) == 5);
assert(!memcmp(buf, pipe_msgs[1], 5));
exit(0);
}
}
close(ends[0]);
for (int i = 0; i < 16; i++) {
assert(_syscall_write(ends[1], pipe_msgs[1], 5, -1, 0) == 5);
_syscall_await();
}
assert(_syscall_write(ends[1], pipe_msgs[1], 5, -1, 0) < 0);
close(ends[1]);
// not a to.do detect when all processes that can read are stuck on writing to the pipe and vice versa
// it seems like linux just lets the process hang endlessly.
}
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