Refactors internal time retrieval and measurement

Introducing a more consistent and portable approach. The primary goals are to
encapsulate platform-specific differences, improve time resolution, and prepare
for long-term compatibility (e.g., Y2038 on WIN64).

Author: marc-mabe

NEWS

@@ -11,6 +11,7 @@ PHP                                                                        NEWS
   . Fix OSS-Fuzz #429429090 (Failed assertion on unset() with uninitialized
     container). (ilutov)
   . Fixed GH-20564 (Don't call autoloaders with pending exception). (ilutov)
+  . Improved accuracy of microtime() and gettimeofday(), up-to 10ns. (marc-mabe)
 
 - Date:
   . Update timelib to 2022.16. (Derick)

UPGRADING.INTERNALS

@@ -56,6 +56,8 @@ PHP 8.6 INTERNALS UPGRADE NOTES
     node.
   . The zend_exception_save() and zend_exception_restore() functions were
     removed.
+  . Introduced a new time-retrieval API zend_time_*. Use this API instead of
+    time(), gettimeofday(), clock_gettime() and timespec_get().
 
 ========================
 2. Build system changes
@@ -71,6 +73,9 @@ PHP 8.6 INTERNALS UPGRADE NOTES
   . Removed the XML_GetCurrentByteCount() libxml compatibility wrapper,
     as it was unused and could return the wrong result.
 
+- ext/date
+  . Deprecated php_time(), Use zend_time_real_get() instead.
+
 - ext/mbstring:
   . Added GB18030-2022 to default encoding list for zh-CN.
 

Zend/Optimizer/zend_func_infos.h

@@ -559,10 +559,8 @@ static const func_info_t func_infos[] = {
 	F1("dechex", MAY_BE_STRING),
 	F1("base_convert", MAY_BE_STRING),
 	F1("number_format", MAY_BE_STRING),
-#if defined(HAVE_GETTIMEOFDAY)
 	F1("microtime", MAY_BE_STRING|MAY_BE_DOUBLE),
 	F1("gettimeofday", MAY_BE_ARRAY|MAY_BE_ARRAY_KEY_STRING|MAY_BE_ARRAY_OF_LONG|MAY_BE_DOUBLE),
-#endif
 #if defined(HAVE_GETRUSAGE)
 	F1("getrusage", MAY_BE_ARRAY|MAY_BE_ARRAY_KEY_STRING|MAY_BE_ARRAY_OF_LONG|MAY_BE_FALSE),
 #endif
@@ -597,9 +595,7 @@ static const func_info_t func_infos[] = {
 	F1("stream_resolve_include_path", MAY_BE_STRING|MAY_BE_FALSE),
 	F1("stream_get_wrappers", MAY_BE_ARRAY|MAY_BE_ARRAY_KEY_LONG|MAY_BE_ARRAY_OF_STRING),
 	F1("stream_get_transports", MAY_BE_ARRAY|MAY_BE_ARRAY_KEY_LONG|MAY_BE_ARRAY_OF_STRING),
-#if defined(HAVE_GETTIMEOFDAY)
 	F1("uniqid", MAY_BE_STRING),
-#endif
 	F1("parse_url", MAY_BE_LONG|MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_ARRAY_KEY_STRING|MAY_BE_ARRAY_OF_LONG|MAY_BE_ARRAY_OF_STRING|MAY_BE_NULL|MAY_BE_FALSE),
 	F1("urlencode", MAY_BE_STRING),
 	F1("urldecode", MAY_BE_STRING),

Zend/zend_time.c

@@ -0,0 +1,55 @@
+/*
+   +----------------------------------------------------------------------+
+   | Copyright (c) The PHP Group                                          |
+   +----------------------------------------------------------------------+
+   | This source file is subject to version 3.01 of the PHP license,      |
+   | that is bundled with this package in the file LICENSE, and is        |
+   | available through the world-wide-web at the following url:           |
+   | https://www.php.net/license/3_01.txt                                 |
+   | If you did not receive a copy of the PHP license and are unable to   |
+   | obtain it through the world-wide-web, please send a note to          |
+   | license@php.net so we can mail you a copy immediately.               |
+   +----------------------------------------------------------------------+
+   | Author: Marc Bennewitz <marc@mabe.berlin>                            |
+   +----------------------------------------------------------------------+
+*/
+
+#include "zend_time.h"
+
+/* Current real/wall-time in seconds */
+ZEND_API time_t zend_time_real_get(void) {
+	return time(NULL);
+}
+
+ZEND_API void zend_time_real_spec(struct timespec *ts) {
+#if defined(HAVE_CLOCK_GETTIME)
+
+	(void) clock_gettime(CLOCK_REALTIME, ts);
+
+#elif defined(HAVE_TIMESPEC_GET)
+
+	(void) timespec_get(ts, TIME_UTC);
+
+#elif defined(HAVE_GETTIMEOFDAY)
+
+	struct timeval tv;
+	(void) gettimeofday(&tv, NULL);
+	zend_time_val2spec(tv, ts);
+
+#else
+
+	ts->tv_sec  = zend_time_real_get();
+	ts->tv_nsec = 0;
+
+#endif
+}
+
+ZEND_API uint64_t zend_time_mono_fallback(void) {
+#if ZEND_HRTIME_AVAILABLE
+	return (uint64_t)zend_hrtime();
+#else
+	struct timespec ts;
+	zend_time_real_spec(&ts);
+	return ((uint64_t) ts.tv_sec * ZEND_NANO_IN_SEC) + ts.tv_nsec;
+#endif
+}

Zend/zend_time.h

@@ -0,0 +1,95 @@
+/*
+   +----------------------------------------------------------------------+
+   | Copyright (c) The PHP Group                                          |
+   +----------------------------------------------------------------------+
+   | This source file is subject to version 3.01 of the PHP license,      |
+   | that is bundled with this package in the file LICENSE, and is        |
+   | available through the world-wide-web at the following url:           |
+   | https://www.php.net/license/3_01.txt                                 |
+   | If you did not receive a copy of the PHP license and are unable to   |
+   | obtain it through the world-wide-web, please send a note to          |
+   | license@php.net so we can mail you a copy immediately.               |
+   +----------------------------------------------------------------------+
+   | Author: Marc Bennewitz <marc@mabe.berlin>                            |
+   +----------------------------------------------------------------------+
+*/
+
+#ifndef ZEND_TIME_H
+#define ZEND_TIME_H
+
+#include "zend_portability.h"
+
+#ifdef PHP_WIN32
+# include "win32/time.h"
+#endif
+#ifdef HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+#include <time.h>
+
+#include "zend_hrtime.h"
+
+#ifndef PHP_WIN32
+# define tv_sec_t time_t
+# define tv_usec_t suseconds_t
+#else
+# define tv_sec_t long
+# define tv_usec_t long
+#endif
+
+#define ZEND_MILLI_IN_SEC 1000U
+#define ZEND_MICRO_IN_SEC 1000000U
+
+BEGIN_EXTERN_C()
+
+/* Assign seconds to timeval */
+static zend_always_inline void zend_time_sec2val(time_t s, struct timeval *tv) {
+	tv->tv_sec  = (tv_sec_t) s;
+	tv->tv_usec = 0;
+}
+
+/* Assign microseconds to timeval */
+static zend_always_inline void zend_time_usec2val(int64_t usec, struct timeval *tv) {
+	tv->tv_sec  = (tv_sec_t) (usec / ZEND_MICRO_IN_SEC);
+	tv->tv_usec = (tv_usec_t) (usec % ZEND_MICRO_IN_SEC);
+
+	if (UNEXPECTED(tv->tv_usec < 0)) {
+		tv->tv_usec += ZEND_MICRO_IN_SEC;
+		tv->tv_sec  -= 1;
+	}
+}
+
+/* Assign double (seconds) to timeval */
+static zend_always_inline void zend_time_dbl2val(double s, struct timeval *tv) {
+	tv->tv_sec  = (tv_sec_t) s;
+	tv->tv_usec = (tv_usec_t) ((s - tv->tv_sec) * ZEND_MICRO_IN_SEC);
+
+	if (UNEXPECTED(tv->tv_usec < 0)) {
+		tv->tv_usec += ZEND_MICRO_IN_SEC;
+		tv->tv_sec  -= 1;
+	} else if (UNEXPECTED(tv->tv_usec >= ZEND_MICRO_IN_SEC)) {
+		// rare, but protects against rounding up to exactly 1 second
+		tv->tv_usec -= ZEND_MICRO_IN_SEC;
+		tv->tv_sec  += 1;
+	}
+}
+
+/* Assign timeval to timespec */
+static zend_always_inline void zend_time_val2spec(struct timeval tv, struct timespec *ts) {
+	ts->tv_sec  = (time_t) tv.tv_sec;
+	ts->tv_nsec = (long) (tv.tv_usec * 1000);
+}
+
+/* Current real/wall-time in seconds */
+ZEND_API time_t zend_time_real_get(void);
+
+/* Current real/wall-time in up-to nano seconds */
+ZEND_API void zend_time_real_spec(struct timespec *ts);
+
+/* Monotonic time in nanoseconds with a fallback to real/wall-time 
+   if no monotonic timer is available */
+ZEND_API uint64_t zend_time_mono_fallback(void);
+
+END_EXTERN_C()
+
+#endif // ZEND_TIME_H

Zend/zend_virtual_cwd.c

@@ -24,10 +24,10 @@
 #include <errno.h>
 #include <stdlib.h>
 #include <fcntl.h>
-#include <time.h>
 
 #include "zend.h"
 #include "zend_virtual_cwd.h"
+#include "zend_time.h"
 
 #ifdef ZEND_WIN32
 #include <io.h>
@@ -577,7 +577,7 @@ static size_t tsrm_realpath_r(char *path, size_t start, size_t len, int *ll, tim
 		if (start && save && CWDG(realpath_cache_size_limit)) {
 			/* cache lookup for absolute path */
 			if (!*t) {
-				*t = time(0);
+				*t = zend_time_real_get();
 			}
 			if ((bucket = realpath_cache_find(path, len, *t)) != NULL) {
 				if (is_dir && !bucket->is_dir) {

configure.ac

@@ -540,6 +540,7 @@ AC_CHECK_FUNCS(m4_normalize([
   asctime_r
   asprintf
   chroot
+  clock_gettime
   ctime_r
   explicit_memset
   fdatasync
@@ -591,6 +592,7 @@ AC_CHECK_FUNCS(m4_normalize([
   strptime
   strtok_r
   symlink
+  timespec_get
   tzset
   unsetenv
   usleep
@@ -1759,6 +1761,7 @@ PHP_ADD_SOURCES([Zend], m4_normalize([
     zend_generators.c
     zend_hash.c
     zend_highlight.c
+    zend_time.c
     zend_hrtime.c
     zend_inheritance.c
     zend_ini_parser.c

docs-old/streams.md

@@ -90,7 +90,7 @@ PHPAPI php_stream *php_stream_sock_open_from_socket(int socket, int persistent);
     /* Convert a socket into a stream. */
 
 PHPAPI php_stream *php_stream_sock_open_host(const char *host, unsigned short port,
-        int socktype, int timeout, int persistent);
+        int socktype, struct timeval *timeout, const char *persistent_id);
     /* Open a connection to a host and return a stream. */
 
 PHPAPI php_stream *php_stream_sock_open_unix(const char *path, int persistent,

ext/calendar/cal_unix.c

@@ -19,7 +19,7 @@
 #include "php.h"
 #include "php_calendar.h"
 #include "sdncal.h"
-#include <time.h>
+#include "zend_time.h"
 
 #define SECS_PER_DAY (24 * 3600)
 
@@ -36,7 +36,7 @@ PHP_FUNCTION(unixtojd)
 	}
 
 	if (tl_is_null) {
-		ts = time(NULL);
+		ts = zend_time_real_get();
 	} else if (tl >= 0) {
 		ts = (time_t) tl;
 	} else {

ext/calendar/easter.c

@@ -20,7 +20,7 @@
 #include "php.h"
 #include "php_calendar.h"
 #include "sdncal.h"
-#include <time.h>
+#include "zend_time.h"
 
 /**
  * If `gm` is true this will return the timestamp at midnight on Easter of the given year. If it is false this
@@ -43,9 +43,8 @@ static void _cal_easter(INTERNAL_FUNCTION_PARAMETERS, bool gm)
 
 	/* Default to the current year if year parameter is not given */
 	if (year_is_null) {
-		time_t a;
+		time_t a = zend_time_real_get();
 		struct tm b, *res;
-		time(&a);
 		res = php_localtime_r(&a, &b);
 		if (!res) {
 			year = 1900;