Add nanosleep syscall

src/Enclave.edl

@@ -19,6 +19,7 @@ enclave {
         int ocall_run_new_task(void);
         void ocall_gettimeofday([out] long* sec, [out] long* us);
         void ocall_clock_gettime(int clockid, [out] long* sec, [out] long* ns);
+        void ocall_nanosleep(long sec, long nsec);
         void ocall_sync(void);
         int ocall_sched_getaffinity([out] int *error, int pid, size_t cpusize, [out, size=cpusize] unsigned char* buf);
         int ocall_sched_setaffinity([out] int *error, int pid, size_t cpusize, [in, size=cpusize] const unsigned char* buf);

src/libos/src/syscall/mod.rs

@@ -211,6 +211,8 @@ pub extern "C" fn dispatch_syscall(
         SYS_GETTIMEOFDAY => do_gettimeofday(arg0 as *mut timeval_t),
         SYS_CLOCK_GETTIME => do_clock_gettime(arg0 as clockid_t, arg1 as *mut timespec_t),
 
+        SYS_NANOSLEEP => do_nanosleep(arg0 as *const timespec_t, arg1 as *mut timespec_t),
+
         SYS_UNAME => do_uname(arg0 as *mut utsname_t),
 
         SYS_PRLIMIT64 => do_prlimit(
@@ -812,6 +814,18 @@ fn do_clock_gettime(clockid: clockid_t, ts_u: *mut timespec_t) -> Result<isize>
     Ok(0)
 }
 
+// TODO: handle remainder
+fn do_nanosleep(req_u: *const timespec_t, rem_u: *mut timespec_t) -> Result<isize> {
+    check_ptr(req_u)?;
+    if !rem_u.is_null() {
+        check_mut_ptr(rem_u)?;
+    }
+
+    let req = timespec_t::from_raw_ptr(req_u)?;
+    time::do_nanosleep(&req)?;
+    Ok(0)
+}
+
 // FIXME: use this
 const MAP_FAILED: *const c_void = ((-1) as i64) as *const c_void;
 

src/libos/src/time/mod.rs

@@ -43,6 +43,16 @@ pub struct timespec_t {
     nsec: i64,
 }
 
+impl timespec_t {
+    pub fn from_raw_ptr(ptr: *const timespec_t) -> Result<timespec_t> {
+        let ts = unsafe { *ptr };
+        if ts.sec < 0 || ts.nsec < 0 || ts.nsec >= 1_000_000_000 {
+            return_errno!(EINVAL, "Invalid timespec fields");
+        }
+        Ok(ts)
+    }
+}
+
 #[allow(non_camel_case_types)]
 pub type clockid_t = i32;
 
@@ -77,6 +87,10 @@ impl ClockID {
 }
 
 pub fn do_clock_gettime(clockid: ClockID) -> Result<timespec_t> {
+    extern "C" {
+        fn ocall_clock_gettime(clockid: clockid_t, sec: *mut time_t, ns: *mut i64) -> sgx_status_t;
+    }
+
     let mut sec = 0;
     let mut nsec = 0;
     unsafe {
@@ -89,12 +103,17 @@ pub fn do_clock_gettime(clockid: ClockID) -> Result<timespec_t> {
     Ok(timespec_t { sec, nsec })
 }
 
+pub fn do_nanosleep(req: &timespec_t) -> Result<()> {
     extern "C" {
-    fn ocall_clock_gettime(clockid: clockid_t, sec: *mut time_t, ns: *mut i64) -> sgx_status_t;
+        fn ocall_nanosleep(sec: time_t, nsec: i64) -> sgx_status_t;
+    }
+    unsafe {
+        ocall_nanosleep(req.sec, req.nsec);
+    }
+    Ok(())
 }
 
 // For SEFS
-
 pub struct OcclumTimeProvider;
 
 impl TimeProvider for OcclumTimeProvider {

src/libos/src/util/mem_util.rs

@@ -9,21 +9,29 @@ pub mod from_user {
 
     /// Check the user pointer is within the readable memory range of the user process
     pub fn check_ptr<T>(user_ptr: *const T) -> Result<()> {
+        if user_ptr.is_null() {
+            return_errno!(EINVAL, "Address 0 is invalid");
+        }
         Ok(())
     }
 
     /// Check the mutable user pointer is within the writable memory of the user process
     pub fn check_mut_ptr<T>(user_ptr: *mut T) -> Result<()> {
+        if user_ptr.is_null() {
+            return_errno!(EINVAL, "Address 0 is invalid");
+        }
         Ok(())
     }
 
     /// Check the readonly array is within the readable memory of the user process
     pub fn check_array<T>(user_buf: *const T, count: usize) -> Result<()> {
+        check_ptr(user_buf);
         Ok(())
     }
 
     /// Check the mutable array is within the writable memory of the user process
     pub fn check_mut_array<T>(user_buf: *mut T, count: usize) -> Result<()> {
+        check_mut_ptr(user_buf);
         Ok(())
     }
 

src/pal/pal.c

@@ -265,6 +265,11 @@ void ocall_clock_gettime(int clockid, time_t* sec, long* ns) {
     *ns = ts.tv_nsec;
 }
 
+void ocall_nanosleep(time_t sec, long nsec) {
+    struct timespec tv = { .tv_sec = sec, .tv_nsec = nsec };
+    nanosleep(&tv, NULL);
+}
+
 int ocall_sched_getaffinity(int* error, int pid, size_t cpusize, unsigned char* buf) {
     int ret = syscall(__NR_sched_getaffinity, pid, cpusize, buf);
     if (error) {

test/Makefile

@@ -7,7 +7,7 @@ TEST_DEPS := dev_null client
 # Tests: need to be compiled and run by test-% target
 TESTS := empty env hello_world malloc mmap file fs_perms getpid spawn sched pipe time \
 	truncate readdir mkdir link tls pthread uname rlimit server \
-	server_epoll unix_socket cout hostfs cpuid rdtsc device
+	server_epoll unix_socket cout hostfs cpuid rdtsc device sleep
 # Benchmarks: need to be compiled and run by bench-% target
 BENCHES := spawn_and_exit_latency pipe_throughput unix_socket_throughput
 

test/sleep/Makefile

@@ -0,0 +1,5 @@
+include ../test_common.mk
+
+EXTRA_C_FLAGS := -Wno-return-stack-address
+EXTRA_LINK_FLAGS :=
+BIN_ARGS :=

test/sleep/main.c

@@ -0,0 +1,174 @@
+#include <time.h>
+#include <unistd.h>
+#include <errno.h>
+#include <assert.h>
+#include "test.h"
+
+// ============================================================================
+// Helper macros
+// ============================================================================
+
+#define S           (1000 * 1000 * 1000)
+#define MS          (1000 * 1000)
+#define US          (1000)
+#define NS          (1)
+
+// ============================================================================
+// Helper functions
+// ============================================================================
+
+static inline void validate_timespec(const struct timespec* tv) {
+    assert(tv->tv_sec >= 0 && tv->tv_nsec >= 0 && tv->tv_nsec < S);
+}
+
+
+// retval = (a < b) ? -1 : ((a > b) ? 1 : 0)
+static int timespec_cmp(const struct timespec *a, const struct timespec *b)
+{
+    validate_timespec(a);
+    validate_timespec(b);
+
+    if (a->tv_sec < b->tv_sec) {
+        return -1;
+    } else if (a->tv_sec > b->tv_sec) {
+        return 1;
+    } else {
+        return a->tv_nsec < b->tv_nsec ? -1 :
+                (a->tv_nsec > b->tv_nsec ? 1 : 0);
+    }
+}
+
+// diff = | a - b |
+static void timespec_diff(const struct timespec *a, const struct timespec *b,
+    struct timespec *diff)
+{
+    validate_timespec(a);
+    validate_timespec(b);
+
+    const struct timespec *begin, *end;
+    if (timespec_cmp(a, b) <= 0) {
+        begin = a; end = b;
+    } else {
+        begin = b; end = a;
+    }
+
+    diff->tv_nsec = end->tv_nsec - begin->tv_nsec;
+    diff->tv_sec = end->tv_sec - begin->tv_sec;
+    if (diff->tv_nsec < 0) {
+        diff->tv_nsec += S;
+        diff->tv_sec -= 1;
+    }
+
+    validate_timespec(diff);
+}
+
+// retval = | a - b | <= precision
+static int timespec_equal(const struct timespec *a, const struct timespec *b,
+    const struct timespec *precision)
+{
+    struct timespec diff;
+    timespec_diff(a, b, &diff);
+    return timespec_cmp(&diff, precision) <= 0;
+}
+
+
+static int check_nanosleep(struct timespec* expected_sleep_period) {
+    // The time obtained from Occlum is not very precise.
+    // Here we take 1 millisecond as the time precision of Occlum.
+    static struct timespec OS_TIME_PRECISION = {
+        .tv_sec = 0,
+        .tv_nsec = 1 * MS,
+    };
+
+    struct timespec begin_timestamp, end_timestamp;
+    clock_gettime(CLOCK_MONOTONIC, &begin_timestamp);
+
+    if (nanosleep(expected_sleep_period, NULL) != 0) {
+        throw_error("nanosleep failed");
+    }
+
+    clock_gettime(CLOCK_MONOTONIC, &end_timestamp);
+    struct timespec actual_sleep_period;
+    timespec_diff(&begin_timestamp, &end_timestamp, &actual_sleep_period);
+
+    return timespec_equal(expected_sleep_period, &actual_sleep_period,
+                          &OS_TIME_PRECISION);
+}
+
+// ============================================================================
+// Test cases
+// ============================================================================
+
+int test_nanosleep_0_second() {
+    struct timespec period_of_0s = { .tv_sec = 0, .tv_nsec = 0 };
+    return check_nanosleep(&period_of_0s);
+}
+
+int test_nanosleep_1_second() {
+    struct timespec period_of_1s = { .tv_sec = 1, .tv_nsec = 0 };
+    return check_nanosleep(&period_of_1s);
+}
+
+int test_nanosleep_10ms() {
+    struct timespec period_of_10ms = { .tv_sec = 0, .tv_nsec = 10 * MS };
+    return check_nanosleep(&period_of_10ms);
+}
+
+// ============================================================================
+// Test cases with invalid arguments
+// ============================================================================
+
+int test_nanosleep_with_null_req() {
+    if (nanosleep(NULL, NULL) != -1 && errno != EINVAL) {
+        throw_error("nanosleep should report error");
+    }
+    return 0;
+}
+
+int test_nanosleep_with_negative_tv_sec() {
+    // nanosleep returns EINVAL if the value in the tv_sec field is negative
+    struct timespec invalid_period = { .tv_sec = -1, .tv_nsec = 0};
+    if (nanosleep(&invalid_period, NULL) != -1 && errno != EINVAL) {
+        throw_error("nanosleep should report EINVAL error");
+    }
+    return 0;
+}
+
+int test_nanosleep_with_negative_tv_nsec() {
+    // nanosleep returns EINVAL if the value in the tv_nsec field
+    // was not in the range 0 to 999999999.
+    struct timespec invalid_period = { .tv_sec = 0, .tv_nsec = -1};
+    if (nanosleep(&invalid_period, NULL) != -1 && errno != EINVAL) {
+        throw_error("nanosleep should report EINVAL error");
+    }
+    return 0;
+}
+
+int test_nanosleep_with_too_large_tv_nsec() {
+    // nanosleep returns EINVAL if the value in the tv_nsec field
+    // was not in the range 0 to 999999999 (10^6 - 1).
+    struct timespec invalid_period = { .tv_sec = 0, .tv_nsec = S};
+    if (nanosleep(&invalid_period, NULL) != -1 && errno != EINVAL) {
+        throw_error("nanosleep should report EINVAL error");
+    }
+    return 0;
+}
+
+// ============================================================================
+// Test suite main
+// ============================================================================
+
+// TODO: test interruption
+static test_case_t test_cases[] = {
+    TEST_CASE(test_nanosleep_0_second),
+    TEST_CASE(test_nanosleep_1_second),
+    TEST_CASE(test_nanosleep_10ms),
+    TEST_CASE(test_nanosleep_with_null_req),
+    TEST_CASE(test_nanosleep_with_negative_tv_sec),
+    TEST_CASE(test_nanosleep_with_negative_tv_nsec),
+    TEST_CASE(test_nanosleep_with_too_large_tv_nsec)
+};
+
+int main() {
+    return test_suite_run(test_cases, ARRAY_SIZE(test_cases));
+}