Unify two separate clock_getres and clock_gettime implementations. NFC

Author: sbc100

system/lib/libc/emscripten_time.c

@@ -34,48 +34,6 @@ weak time_t __time(time_t *t) {
 static thread_local bool checked_monotonic = false;
 static thread_local bool is_monotonic = 0;
 
-weak int __clock_gettime(clockid_t clk, struct timespec *ts) {
-  if (!checked_monotonic) {
-    is_monotonic = _emscripten_get_now_is_monotonic();
-    checked_monotonic = true;
-  }
-
-  double now_ms;
-  if (clk == CLOCK_REALTIME) {
-    now_ms = emscripten_date_now();
-  } else if ((clk == CLOCK_MONOTONIC || clk == CLOCK_MONOTONIC_RAW) && is_monotonic) {
-    now_ms = emscripten_get_now();
-  } else {
-    errno = EINVAL;
-    return -1;
-  }
-
-  long long now_s = now_ms / 1000;
-  ts->tv_sec = now_s; // seconds
-  ts->tv_nsec = (now_ms - (now_s * 1000)) * 1000 * 1000; // nanoseconds
-  return 0;
-}
-
-weak int __clock_getres(clockid_t clk, struct timespec *ts) {
-  if (!checked_monotonic) {
-    is_monotonic = _emscripten_get_now_is_monotonic();
-    checked_monotonic = true;
-  }
-
-  double nsec;
-  if (clk == CLOCK_REALTIME) {
-    nsec = 1000 * 1000; // educated guess that it's milliseconds
-  } else if (clk == CLOCK_MONOTONIC && is_monotonic) {
-    nsec = emscripten_get_now_res();
-  } else {
-    errno = EINVAL;
-    return -1;
-  }
-  ts->tv_sec = (nsec / (1000 * 1000 * 1000));
-  ts->tv_nsec = nsec;
-  return 0;
-}
-
 weak int __gettimeofday(struct timeval *restrict tv, void *restrict tz) {
   double now_ms = emscripten_date_now();
   long long now_s = now_ms / 1000;
@@ -91,6 +49,4 @@ weak int dysize(int year) {
 
 weak_alias(__time, time);
 weak_alias(__clock, clock);
-weak_alias(__clock_gettime, clock_gettime);
-weak_alias(__clock_getres, clock_getres);
 weak_alias(__gettimeofday, gettimeofday);

system/lib/libc/musl/src/time/clock_getres.c

@@ -3,6 +3,20 @@
 
 int clock_getres(clockid_t clk, struct timespec *ts)
 {
+#ifdef __EMSCRIPTEN__
+	// See https://github.com/bytecodealliance/wasmtime/issues/374
+	if (clk > __WASI_CLOCKID_THREAD_CPUTIME_ID || clk < 0) {
+		errno = EINVAL;
+		return -1;
+	}
+	__wasi_timestamp_t res;
+	__wasi_errno_t error = __wasi_clock_res_get(clk, &res);
+	if (error != __WASI_ERRNO_SUCCESS) {
+		return __wasi_syscall_ret(error);
+	}
+	*ts = __wasi_timestamp_to_timespec(res);
+	return 0;
+#else
 #ifdef SYS_clock_getres_time64
 	/* On a 32-bit arch, use the old syscall if it exists. */
 	if (SYS_clock_getres != SYS_clock_getres_time64) {
@@ -18,4 +32,5 @@ int clock_getres(clockid_t clk, struct timespec *ts)
 	/* If reaching this point, it's a 64-bit arch or time64-only
 	 * 32-bit arch and we can get result directly into timespec. */
 	return syscall(SYS_clock_getres, clk, ts);
+#endif
 }

system/lib/libc/wasi-helpers.c

@@ -7,6 +7,7 @@
 
 #include <errno.h>
 #include <stdlib.h>
+#include <time.h>
 #include <wasi/api.h>
 #include <wasi/wasi-helpers.h>
 
@@ -26,3 +27,10 @@ int  __wasi_fd_is_valid(__wasi_fd_t fd) {
   }
   return 1;
 }
+
+#define NSEC_PER_SEC (1000 * 1000 * 1000)
+
+struct timespec __wasi_timestamp_to_timespec(__wasi_timestamp_t timestamp) {
+  return (struct timespec){.tv_sec = timestamp / NSEC_PER_SEC,
+                           .tv_nsec = timestamp % NSEC_PER_SEC};
+}

system/lib/standalone/standalone.c

@@ -45,28 +45,6 @@ _Static_assert(CLOCK_MONOTONIC == __WASI_CLOCKID_MONOTONIC, "must match");
 _Static_assert(CLOCK_PROCESS_CPUTIME_ID == __WASI_CLOCKID_PROCESS_CPUTIME_ID, "must match");
 _Static_assert(CLOCK_THREAD_CPUTIME_ID == __WASI_CLOCKID_THREAD_CPUTIME_ID, "must match");
 
-#define NSEC_PER_SEC (1000 * 1000 * 1000)
-
-struct timespec __wasi_timestamp_to_timespec(__wasi_timestamp_t timestamp) {
-  return (struct timespec){.tv_sec = timestamp / NSEC_PER_SEC,
-                           .tv_nsec = timestamp % NSEC_PER_SEC};
-}
-
-int clock_getres(clockid_t clk_id, struct timespec *tp) {
-  // See https://github.com/bytecodealliance/wasmtime/issues/3714
-  if (clk_id > __WASI_CLOCKID_THREAD_CPUTIME_ID || clk_id < 0) {
-    errno = EINVAL;
-    return -1;
-  }
-  __wasi_timestamp_t res;
-  __wasi_errno_t error = __wasi_clock_res_get(clk_id, &res);
-  if (error != __WASI_ERRNO_SUCCESS) {
-    return __wasi_syscall_ret(error);
-  }
-  *tp = __wasi_timestamp_to_timespec(res);
-  return 0;
-}
-
 // mmap support is nonexistent. TODO: emulate simple mmaps using
 // stdio + malloc, which is slow but may help some things?
 

test/other/codesize/test_codesize_minimal_pthreads.gzsize

@@ -1 +1 @@
-4218
+4306

test/other/codesize/test_codesize_minimal_pthreads.jssize

@@ -1 +1 @@
-8696
+8921

test/other/codesize/test_codesize_minimal_pthreads.size

@@ -1 +1 @@
-19501
+19497

tools/system_libs.py

@@ -1224,6 +1224,8 @@ def get_files(self):
           'localtime.c',
           'nanosleep.c',
           'clock_nanosleep.c',
+          'clock_getres.c',
+          'clock_gettime.c',
           'ctime_r.c',
           'timespec_get.c',
           'utime.c',
@@ -2215,7 +2217,6 @@ def get_files(self):
         filenames=['__secs_to_tm.c',
                    '__tz.c',
                    'clock.c',
-                   'clock_gettime.c',
                    'gettimeofday.c',
                    'localtime_r.c',
                    'gmtime_r.c',