user: reorganize the userland sources

5 files changed, 456 insertions, 0 deletions

diff --git a/src/user/tests/main.c b/src/user/tests/main.c
new file mode 100644
index 0000000..fd5ffca
--- /dev/null
+++ b/src/user/tests/main.c
@@ -0,0 +1,205 @@
+#define TEST_MACROS
+#include <user/lib/stdlib.h>
+#include <user/tests/main.h>
+#include <shared/flags.h>
+#include <shared/syscalls.h>
+
+static void run_forked(void (*fn)()) {
+	if (!_syscall_fork(0, NULL)) {
+		fn();
+		_syscall_exit(0);
+	} else {
+		/* successful tests must return 0
+		 * TODO add a better fail msg */
+		if (_syscall_await() != 0) test_fail();
+	}
+}
+
+
+
+static void test_await(void) {
+	/* creates 16 child processes, each returning a different value. then checks
+	 * if await() returns every value exactly once */
+	int ret;
+	int counts[16] = {0};
+
+	for (int i = 0; i < 16; i++)
+		if (!_syscall_fork(0, NULL))
+			_syscall_exit(i);
+
+	while ((ret = _syscall_await()) != ~0) {
+		assert(0 <= ret && ret < 16);
+		counts[ret]++;
+	}
+
+	for (int i = 0; i < 16; i++)
+		assert(counts[i] == 1);
+}
+
+static void test_faults(void) {
+	/* tests what happens when child processes fault.
+	 * expected behavior: parent processes still manages to finish, and it can
+	 * reap all its children */
+	int await_cnt = 0;
+
+	if (!_syscall_fork(0, NULL)) { // invalid memory access
+		asm volatile("movb $69, 0" ::: "memory");
+		printf("this shouldn't happen");
+		_syscall_exit(-1);
+	}
+	if (!_syscall_fork(0, NULL)) { // #GP
+		asm volatile("hlt" ::: "memory");
+		printf("this shouldn't happen");
+		_syscall_exit(-1);
+	}
+
+	while (_syscall_await() != ~0) await_cnt++;
+	assert(await_cnt == 2);
+}
+
+static void test_interrupted_fs(void) {
+	handle_t h;
+	if (_syscall_fork(FORK_NEWFS, &h)) { /* child */
+		// TODO make a similar test with all 0s passed to fs_wait
+		struct fs_wait_response res;
+		_syscall_fs_wait(NULL, 0, &res);
+		_syscall_exit(0);
+	} else { /* parent */
+		_syscall_mount(h, "/", 1);
+		int ret = _syscall_open("/", 1, 0);
+		// the handler quits while handling that call - but this syscall should return anyways
+		_syscall_exit(ret < 0 ? 0 : -1);
+	}
+}
+
+static void test_orphaned_fs(void) {
+	handle_t h;
+	if (_syscall_fork(FORK_NEWFS, &h)) { /* child */
+		_syscall_exit(0);
+	} else { /* parent */
+		_syscall_mount(h, "/", 1);
+		int ret = _syscall_open("/", 1, 0);
+		// no handler will ever be available to handle this call - the syscall should instantly return
+		_syscall_exit(ret < 0 ? 0 : -1);
+	}
+}
+
+static void test_memflag(void) {
+	void *page = (void*)0x77777000;
+	_syscall_memflag(page, 4096, MEMFLAG_PRESENT); // allocate page
+	memset(page, 77, 4096); // write to it
+	_syscall_memflag(page, 4096, 0); // free it
+
+	if (!_syscall_fork(0, NULL)) {
+		memset(page, 11, 4096); // should segfault
+		_syscall_exit(0);
+	} else {
+		assert(_syscall_await() != 0); // test if the process crashed
+	}
+
+	char *pages[4];
+	for (size_t i = 0; i < 4; i++) {
+		pages[i] = _syscall_memflag(NULL, 4096, MEMFLAG_FINDFREE);
+		printf("[test_memflag] findfree: 0x%x\n", pages[i]);
+
+		assert(pages[i] == _syscall_memflag(NULL, 4096, MEMFLAG_FINDFREE | MEMFLAG_PRESENT));
+		if (i > 0) assert(pages[i] != pages[i-1]);
+		*pages[i] = 0x77;
+	}
+
+	for (size_t i = 0; i < 4; i++)
+		_syscall_memflag(pages, 4096, MEMFLAG_PRESENT);
+
+	// TODO check if reclaims
+}
+
+static void test_dup(void) {
+	handle_t pipe[2];
+	handle_t h1, h2;
+	assert(_syscall_pipe(pipe, 0) >= 0);
+
+	if (!_syscall_fork(0, NULL)) {
+		_syscall_close(pipe[0]);
+
+		h1 = _syscall_dup(pipe[1], -1, 0);
+		assert(h1 >= 0);
+		assert(h1 != pipe[1]);
+		h2 = _syscall_dup(h1, -1, 0);
+		assert(h2 >= 0);
+		assert(h2 != pipe[1] && h2 != h1);
+
+		_syscall_write(pipe[1], "og", 2, 0);
+		_syscall_write(h1, "h1", 2, 0);
+		_syscall_write(h2, "h2", 2, 0);
+
+		_syscall_close(pipe[1]);
+		_syscall_write(h1, "h1", 2, 0);
+		_syscall_write(h2, "h2", 2, 0);
+
+		assert(_syscall_dup(h1, pipe[1], 0) == pipe[1]);
+		assert(_syscall_dup(h2, pipe[1], 0) == pipe[1]);
+		assert(_syscall_dup(h1, pipe[1], 0) == pipe[1]);
+		assert(_syscall_dup(h2, pipe[1], 0) == pipe[1]);
+		_syscall_close(h1);
+		_syscall_close(h2);
+
+		assert(_syscall_dup(pipe[1], h2, 0) == h2);
+		_syscall_write(h2, "h2", 2, 0);
+		_syscall_close(h2);
+
+		assert(_syscall_dup(pipe[1], h1, 0) == h1);
+		_syscall_write(h1, "h1", 2, 0);
+		_syscall_close(h1);
+
+		_syscall_exit(0);
+	} else {
+		char buf[16];
+		size_t count = 0;
+		_syscall_close(pipe[1]);
+		while (_syscall_read(pipe[0], buf, sizeof buf, 0) >= 0)
+			count++;
+		assert(count == 7);
+		_syscall_await();
+	}
+
+
+	_syscall_close(pipe[0]);
+}
+
+static void test_malloc(void) {
+	// not really a test
+	void *p1, *p2;
+
+	p1 = malloc(420);
+	printf("p1 = 0x%x\n", p1);
+
+	p2 = malloc(1024);
+	printf("p2 = 0x%x\n", p2);
+	free(p2);
+	p2 = malloc(256);
+	printf("p2 = 0x%x\n", p2);
+	free(p2);
+	p2 = malloc(4096);
+	printf("p2 = 0x%x\n", p2);
+	free(p2);
+
+	free(p1);
+}
+
+static void test_misc(void) {
+	assert(_syscall(~0, 0, 0, 0, 0) < 0); /* try making an invalid syscall */
+}
+
+
+void test_all(void) {
+	run_forked(test_await);
+	run_forked(test_faults);
+	run_forked(test_interrupted_fs);
+	run_forked(test_orphaned_fs);
+	run_forked(test_memflag);
+	run_forked(test_dup);
+	run_forked(test_malloc);
+	run_forked(test_pipe);
+	run_forked(test_semaphore);
+	run_forked(test_misc);
+}
diff --git a/src/user/tests/main.h b/src/user/tests/main.h
new file mode 100644
index 0000000..ed11c5e
--- /dev/null
+++ b/src/user/tests/main.h
@@ -0,0 +1,18 @@
+#pragma once
+
+void stress_all(void);
+void test_all(void);
+
+void test_pipe(void);
+void test_semaphore(void);
+
+#ifdef TEST_MACROS
+
+#define argify(str) str, sizeof(str) - 1
+#define test_fail() do { \
+	printf("\033[31m" "TEST FAILED: %s:%xh\n" "\033[0m", __func__, __LINE__); \
+	_syscall_exit(0); \
+} while (0)
+#define assert(cond) if (!(cond)) test_fail();
+
+#endif
diff --git a/src/user/tests/pipe.c b/src/user/tests/pipe.c
new file mode 100644
index 0000000..e973993
--- /dev/null
+++ b/src/user/tests/pipe.c
@@ -0,0 +1,116 @@
+#define TEST_MACROS
+#include <user/lib/stdlib.h>
+#include <user/tests/main.h>
+#include <shared/flags.h>
+#include <shared/syscalls.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 (!_syscall_fork(0, NULL)) {
+		/* 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);
+
+		ret = _syscall_write(ends[1], pipe_msgs[0], 5, -1);
+		assert(ret == 5);
+
+		assert(_syscall_read(ends[1], buf, 16, 0) < 0);
+		assert(_syscall_write(ends[0], buf, 16, 0) < 0);
+
+		ret = _syscall_write(ends[1], pipe_msgs[1], 5, -1);
+		assert(ret == 5);
+
+		_syscall_exit(0);
+	} else {
+		assert(_syscall_read(ends[1], buf, 16, 0) < 0);
+		assert(_syscall_write(ends[0], buf, 16, 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);
+
+		_syscall_read(ends[0], buf, 16, 0);
+		assert(ret == 5);
+		assert(!memcmp(buf, pipe_msgs[1], 5));
+
+		_syscall_await();
+	}
+	_syscall_close(ends[0]);
+	_syscall_close(ends[1]);
+
+
+	/* writing to pipes with one end closed */
+	assert(_syscall_pipe(ends, 0) >= 0);
+	for (int i = 0; i < 16; i++) {
+		if (!_syscall_fork(0, NULL)) {
+			_syscall_close(ends[1]);
+			assert(_syscall_read(ends[0], buf, 16, 0) < 0);
+			_syscall_exit(0);
+		}
+	}
+	_syscall_close(ends[1]);
+	for (int i = 0; i < 16; i++)
+		_syscall_await();
+	_syscall_close(ends[0]);
+
+	assert(_syscall_pipe(ends, 0) >= 0);
+	for (int i = 0; i < 16; i++) {
+		if (!_syscall_fork(0, NULL)) {
+			_syscall_close(ends[0]);
+			assert(_syscall_write(ends[1], buf, 16, 0) < 0);
+			_syscall_exit(0);
+		}
+	}
+	_syscall_close(ends[0]);
+	for (int i = 0; i < 16; i++)
+		_syscall_await();
+	_syscall_close(ends[1]);
+
+
+	/* queueing */
+	assert(_syscall_pipe(ends, 0) >= 0);
+	for (int i = 0; i < 16; i++) {
+		if (!_syscall_fork(0, NULL)) {
+			assert(_syscall_write(ends[1], pipe_msgs[0], 5, -1) == 5);
+			_syscall_exit(0);
+		}
+	}
+	_syscall_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);
+	_syscall_close(ends[0]);
+
+	assert(_syscall_pipe(ends, 0) >= 0);
+	for (int i = 0; i < 16; i++) {
+		if (!_syscall_fork(0, NULL)) {
+			memset(buf, 0, sizeof buf);
+			assert(_syscall_read(ends[0], buf, 5, -1) == 5);
+			assert(!memcmp(buf, pipe_msgs[1], 5));
+			_syscall_exit(0);
+		}
+	}
+	_syscall_close(ends[0]);
+	for (int i = 0; i < 16; i++) {
+		assert(_syscall_write(ends[1], pipe_msgs[1], 5, -1) == 5);
+		_syscall_await();
+	}
+	assert(_syscall_write(ends[1], pipe_msgs[1], 5, -1) < 0);
+	_syscall_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.
+}
diff --git a/src/user/tests/semaphore.c b/src/user/tests/semaphore.c
new file mode 100644
index 0000000..e5aacaa
--- /dev/null
+++ b/src/user/tests/semaphore.c
@@ -0,0 +1,89 @@
+#define TEST_MACROS
+#include <user/lib/esemaphore.h>
+#include <user/lib/stdlib.h>
+#include <user/tests/main.h>
+#include <shared/flags.h>
+#include <shared/syscalls.h>
+
+static void odd(handle_t out, struct evil_sem *sem1, struct evil_sem *sem2) {
+	_syscall_write(out, "1", 1, -1);
+	esem_signal(sem1);
+
+	esem_wait(sem2);
+	_syscall_write(out, "3", 1, -1);
+	esem_signal(sem1);
+
+	esem_wait(sem2);
+	_syscall_write(out, "5", 1, -1);
+	esem_signal(sem1);
+}
+
+static void even(handle_t out, struct evil_sem *sem1, struct evil_sem *sem2) {
+	esem_wait(sem1);
+	_syscall_write(out, "2", 1, -1);
+	esem_signal(sem2);
+
+	esem_wait(sem1);
+	_syscall_write(out, "4", 1, -1);
+	esem_signal(sem2);
+
+	esem_wait(sem1);
+	_syscall_write(out, "6", 1, -1);
+	esem_signal(sem2);
+}
+
+void test_semaphore(void) {
+	struct evil_sem *sem1, *sem2;
+	handle_t pipe[2];
+	assert(_syscall_pipe(pipe, 0) >= 0);
+
+	if (!_syscall_fork(0, NULL)) {
+		sem1 = esem_new(0);
+		sem2 = esem_new(0);
+		assert(sem1 && sem2);
+		if (!_syscall_fork(0, NULL)) {
+			odd(pipe[1], sem1, sem2);
+			_syscall_exit(69);
+		} else {
+			even(pipe[1], sem1, sem2);
+			assert(_syscall_await() == 69);
+		}
+		esem_free(sem1);
+		esem_free(sem2);
+
+		_syscall_write(pipe[1], "|", 1, -1);
+
+		sem1 = esem_new(0);
+		sem2 = esem_new(0);
+		assert(sem1 && sem2);
+		if (!_syscall_fork(0, NULL)) {
+			even(pipe[1], sem1, sem2);
+			_syscall_exit(69);
+		} else {
+			odd(pipe[1], sem1, sem2);
+			assert(_syscall_await() == 69);
+			_syscall_await();
+		}
+		esem_free(sem1);
+		esem_free(sem2);
+
+		_syscall_exit(0);
+	} else {
+		_syscall_close(pipe[1]);
+
+		char buf[16];
+		size_t pos = 0;
+		for (;;) {
+			int ret = _syscall_read(pipe[0], buf + pos, sizeof(buf) - pos, 0);
+			if (ret < 0) break;
+			pos += ret;
+		}
+		buf[pos] = '\0'; // idc about the "potential" overflow
+		if (strcmp(buf, "123456|123456")) {
+			printf("%s\n", buf);
+			test_fail();
+		}
+
+		_syscall_await();
+	}
+}
diff --git a/src/user/tests/stress.c b/src/user/tests/stress.c
new file mode 100644
index 0000000..51b9c4e
--- /dev/null
+++ b/src/user/tests/stress.c
@@ -0,0 +1,28 @@
+#define TEST_MACROS
+#include <user/lib/stdlib.h>
+#include <user/tests/main.h>
+#include <shared/flags.h>
+#include <shared/syscalls.h>
+
+static void run_forked(void (*fn)()) {
+	if (!_syscall_fork(0, NULL)) {
+		fn();
+		_syscall_exit(0);
+	} else {
+		/* successful tests must return 0
+		 * TODO add a better fail msg */
+		if (_syscall_await() != 0) test_fail();
+	}
+}
+
+
+static void stress_fork(void) {
+	for (size_t i = 0; i < 2048; i++) {
+		if (!_syscall_fork(0, NULL)) _syscall_exit(0);
+		_syscall_await();
+	}
+}
+
+void stress_all(void) {
+	run_forked(stress_fork);
+}