From 684a9793738321f354b55d138323eceab22dcd02 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Fri, 29 Jan 2021 19:24:10 +0000
Subject: [PATCH 01/18] fsync initial

---
 ext/standard/basic_functions_arginfo.h |  2 ++
 ext/standard/file.c                    | 20 ++++++++++++++++++++
 ext/standard/file.h                    |  1 +
 main/php_streams.h                     |  4 ++++
 main/streams/plain_wrapper.c           | 16 ++++++++++++++++
 main/streams/streams.c                 |  9 +++++++++
 6 files changed, 52 insertions(+)

diff --git a/ext/standard/basic_functions_arginfo.h b/ext/standard/basic_functions_arginfo.h
index 5eafa59b50bd..1c67d5545f0f 100644
--- a/ext/standard/basic_functions_arginfo.h
+++ b/ext/standard/basic_functions_arginfo.h
@@ -2560,6 +2560,7 @@ ZEND_FUNCTION(fstat);
 ZEND_FUNCTION(fseek);
 ZEND_FUNCTION(ftell);
 ZEND_FUNCTION(fflush);
+ZEND_FUNCTION(fsync);
 ZEND_FUNCTION(fwrite);
 ZEND_FUNCTION(mkdir);
 ZEND_FUNCTION(rename);
@@ -3197,6 +3198,7 @@ static const zend_function_entry ext_functions[] = {
 	ZEND_FE(fseek, arginfo_fseek)
 	ZEND_FE(ftell, arginfo_ftell)
 	ZEND_FE(fflush, arginfo_fflush)
+	ZEND_FE(fsync, arginfo_fflush)
 	ZEND_FE(fwrite, arginfo_fwrite)
 	ZEND_FALIAS(fputs, fwrite, arginfo_fputs)
 	ZEND_FE(mkdir, arginfo_mkdir)
diff --git a/ext/standard/file.c b/ext/standard/file.c
index 6eb85ed73948..1ae72c75147a 100644
--- a/ext/standard/file.c
+++ b/ext/standard/file.c
@@ -1170,6 +1170,26 @@ PHPAPI PHP_FUNCTION(fwrite)
 }
 /* }}} */
 
+PHPAPI PHP_FUNCTION(fsync)
+{
+	zval *res;
+	int ret;
+	php_stream *stream;
+
+	ZEND_PARSE_PARAMETERS_START(1, 1)
+		Z_PARAM_RESOURCE(res)
+	ZEND_PARSE_PARAMETERS_END();
+
+	PHP_STREAM_TO_ZVAL(stream, res);
+
+	ret = php_stream_sync(stream);
+	if (ret) {
+		RETURN_FALSE;
+	}
+	RETURN_TRUE;
+
+}
+
 /* {{{ Flushes output */
 PHPAPI PHP_FUNCTION(fflush)
 {
diff --git a/ext/standard/file.h b/ext/standard/file.h
index f9d153a52a5d..9cf007a0f062 100644
--- a/ext/standard/file.h
+++ b/ext/standard/file.h
@@ -29,6 +29,7 @@ PHPAPI PHP_FUNCTION(fgetc);
 PHPAPI PHP_FUNCTION(fgets);
 PHPAPI PHP_FUNCTION(fwrite);
 PHPAPI PHP_FUNCTION(fflush);
+PHPAPI PHP_FUNCTION(fsync);
 PHPAPI PHP_FUNCTION(rewind);
 PHPAPI PHP_FUNCTION(ftell);
 PHPAPI PHP_FUNCTION(fseek);
diff --git a/main/php_streams.h b/main/php_streams.h
index 60be0a79eb49..3a36a7bb3e72 100644
--- a/main/php_streams.h
+++ b/main/php_streams.h
@@ -117,6 +117,7 @@ typedef struct _php_stream_ops  {
 	ssize_t (*read)(php_stream *stream, char *buf, size_t count);
 	int    (*close)(php_stream *stream, int close_handle);
 	int    (*flush)(php_stream *stream);
+	int    (*sync)(php_stream *stream);
 
 	const char *label; /* label for this ops structure */
 
@@ -336,6 +337,9 @@ PHPAPI int _php_stream_putc(php_stream *stream, int c);
 PHPAPI int _php_stream_flush(php_stream *stream, int closing);
 #define php_stream_flush(stream)	_php_stream_flush((stream), 0)
 
+PHPAPI int _php_stream_sync(php_stream *stream);
+#define php_stream_sync(stream)	        _php_stream_sync((stream))
+
 PHPAPI char *_php_stream_get_line(php_stream *stream, char *buf, size_t maxlen, size_t *returned_len);
 #define php_stream_gets(stream, buf, maxlen)	_php_stream_get_line((stream), (buf), (maxlen), NULL)
 
diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index a63c225a0da5..f75f9ac00494 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -520,6 +520,21 @@ static int php_stdiop_close(php_stream *stream, int close_handle)
 	return ret;
 }
 
+//dwg
+static int php_stdiop_sync(php_stream *stream)
+{
+	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
+
+	assert(data != NULL);
+
+	if (data->file) {
+		fflush(data->file);
+		return fsync(fileno(data->file));
+	}
+	return 0;
+	
+}
+
 static int php_stdiop_flush(php_stream *stream)
 {
 	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
@@ -958,6 +973,7 @@ static int php_stdiop_set_option(php_stream *stream, int option, int value, void
 PHPAPI php_stream_ops	php_stream_stdio_ops = {
 	php_stdiop_write, php_stdiop_read,
 	php_stdiop_close, php_stdiop_flush,
+	php_stdiop_sync,
 	"STDIO",
 	php_stdiop_seek,
 	php_stdiop_cast,
diff --git a/main/streams/streams.c b/main/streams/streams.c
index 86522afa8475..2ae6d5989818 100644
--- a/main/streams/streams.c
+++ b/main/streams/streams.c
@@ -1224,6 +1224,15 @@ static ssize_t _php_stream_write_filtered(php_stream *stream, const char *buf, s
 	return consumed;
 }
 
+PHPAPI int _php_stream_sync(php_stream *stream)
+{
+	int ret = 0;
+	if (stream->ops->sync) {
+		ret = stream->ops->sync(stream);
+	}
+	return ret;
+}
+
 PHPAPI int _php_stream_flush(php_stream *stream, int closing)
 {
 	int ret = 0;

From 89e0c2f829bb5d2ce685932815ecaf30e5ccf2e6 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Fri, 29 Jan 2021 23:52:43 +0000
Subject: [PATCH 02/18] fix warnings regarding stream_ops order

---
 main/php_streams.h           |  2 +-
 main/streams/glob_wrapper.c  |  3 ++-
 main/streams/plain_wrapper.c | 14 ++++++++------
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/main/php_streams.h b/main/php_streams.h
index 3a36a7bb3e72..76429bfbe13c 100644
--- a/main/php_streams.h
+++ b/main/php_streams.h
@@ -117,7 +117,6 @@ typedef struct _php_stream_ops  {
 	ssize_t (*read)(php_stream *stream, char *buf, size_t count);
 	int    (*close)(php_stream *stream, int close_handle);
 	int    (*flush)(php_stream *stream);
-	int    (*sync)(php_stream *stream);
 
 	const char *label; /* label for this ops structure */
 
@@ -126,6 +125,7 @@ typedef struct _php_stream_ops  {
 	int (*cast)(php_stream *stream, int castas, void **ret);
 	int (*stat)(php_stream *stream, php_stream_statbuf *ssb);
 	int (*set_option)(php_stream *stream, int option, int value, void *ptrparam);
+        int (*sync)(php_stream *stream);
 } php_stream_ops;
 
 typedef struct _php_stream_wrapper_ops {
diff --git a/main/streams/glob_wrapper.c b/main/streams/glob_wrapper.c
index 212d905e1609..b1b5fd96d095 100644
--- a/main/streams/glob_wrapper.c
+++ b/main/streams/glob_wrapper.c
@@ -190,7 +190,8 @@ const php_stream_ops  php_glob_stream_ops = {
 	php_glob_stream_rewind,
 	NULL, /* cast */
 	NULL, /* stat */
-	NULL  /* set_option */
+	NULL,  /* set_option */
+	NULL
 };
 
  /* {{{ php_glob_stream_opener */
diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index f75f9ac00494..7cd9eccbf008 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -524,15 +524,17 @@ static int php_stdiop_close(php_stream *stream, int close_handle)
 static int php_stdiop_sync(php_stream *stream)
 {
 	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
+	int ret = 0;
 
 	assert(data != NULL);
 
 	if (data->file) {
-		fflush(data->file);
-		return fsync(fileno(data->file));
+		ret = fflush(data->file);
+		if (ret != 0) {
+		    return fsync(fileno(data->file));
+		}
 	}
-	return 0;
-	
+	return ret;	
 }
 
 static int php_stdiop_flush(php_stream *stream)
@@ -973,12 +975,12 @@ static int php_stdiop_set_option(php_stream *stream, int option, int value, void
 PHPAPI php_stream_ops	php_stream_stdio_ops = {
 	php_stdiop_write, php_stdiop_read,
 	php_stdiop_close, php_stdiop_flush,
-	php_stdiop_sync,
 	"STDIO",
 	php_stdiop_seek,
 	php_stdiop_cast,
 	php_stdiop_stat,
-	php_stdiop_set_option
+	php_stdiop_set_option,
+	php_stdiop_sync,
 };
 /* }}} */
 

From f42d8bcaf40135dae369412b4764188e69d7e6fa Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sat, 30 Jan 2021 15:57:25 +0000
Subject: [PATCH 03/18] Implement fsync via set_option

---
 ext/standard/basic_functions.stub.php |  3 ++
 ext/standard/file.c                   | 48 ++++++++++++++++-----------
 main/php_streams.h                    | 11 ++++--
 main/streams/glob_wrapper.c           |  3 +-
 main/streams/plain_wrapper.c          | 14 +++++---
 main/streams/streams.c                | 14 +++-----
 6 files changed, 56 insertions(+), 37 deletions(-)

diff --git a/ext/standard/basic_functions.stub.php b/ext/standard/basic_functions.stub.php
index 99d0d3c63db7..0e17f444bca3 100755
--- a/ext/standard/basic_functions.stub.php
+++ b/ext/standard/basic_functions.stub.php
@@ -823,6 +823,9 @@ function ftell($stream): int|false {}
 /** @param resource $stream */
 function fflush($stream): bool {}
 
+/** @param resource $stream */
+function fsync($stream): bool {}
+
 /** @param resource $stream */
 function fwrite($stream, string $data, ?int $length = null): int|false {}
 
diff --git a/ext/standard/file.c b/ext/standard/file.c
index 1ae72c75147a..aeddb1993054 100644
--- a/ext/standard/file.c
+++ b/ext/standard/file.c
@@ -1170,26 +1170,6 @@ PHPAPI PHP_FUNCTION(fwrite)
 }
 /* }}} */
 
-PHPAPI PHP_FUNCTION(fsync)
-{
-	zval *res;
-	int ret;
-	php_stream *stream;
-
-	ZEND_PARSE_PARAMETERS_START(1, 1)
-		Z_PARAM_RESOURCE(res)
-	ZEND_PARSE_PARAMETERS_END();
-
-	PHP_STREAM_TO_ZVAL(stream, res);
-
-	ret = php_stream_sync(stream);
-	if (ret) {
-		RETURN_FALSE;
-	}
-	RETURN_TRUE;
-
-}
-
 /* {{{ Flushes output */
 PHPAPI PHP_FUNCTION(fflush)
 {
@@ -1487,6 +1467,34 @@ PHP_FUNCTION(unlink)
 }
 /* }}} */
 
+/* {{{ Sync file to storage. Similar to fflush() but blocks until OS buffers have flushed. */
+PHP_FUNCTION(fsync)
+{
+	zval *res;
+	int ret;
+	php_stream *stream;
+
+	ZEND_PARSE_PARAMETERS_START(1, 1)
+		Z_PARAM_RESOURCE(res)
+	ZEND_PARSE_PARAMETERS_END();
+
+	PHP_STREAM_TO_ZVAL(stream, res);
+
+	if (!php_stream_sync_supported(stream)) {
+		php_error_docref(NULL, E_WARNING, "Can't fsync this stream!");
+		RETURN_FALSE;
+	}
+
+	ret = php_stream_sync(stream);
+	if (ret) {
+		RETURN_FALSE;
+	}
+	RETURN_TRUE;
+
+}
+/* }}} */
+
+
 /* {{{ Truncate file to 'size' length */
 PHP_FUNCTION(ftruncate)
 {
diff --git a/main/php_streams.h b/main/php_streams.h
index 76429bfbe13c..1437f01d2c62 100644
--- a/main/php_streams.h
+++ b/main/php_streams.h
@@ -125,7 +125,6 @@ typedef struct _php_stream_ops  {
 	int (*cast)(php_stream *stream, int castas, void **ret);
 	int (*stat)(php_stream *stream, php_stream_statbuf *ssb);
 	int (*set_option)(php_stream *stream, int option, int value, void *ptrparam);
-        int (*sync)(php_stream *stream);
 } php_stream_ops;
 
 typedef struct _php_stream_wrapper_ops {
@@ -338,7 +337,7 @@ PHPAPI int _php_stream_flush(php_stream *stream, int closing);
 #define php_stream_flush(stream)	_php_stream_flush((stream), 0)
 
 PHPAPI int _php_stream_sync(php_stream *stream);
-#define php_stream_sync(stream)	        _php_stream_sync((stream))
+#define php_stream_sync(stream)	    _php_stream_sync((stream))
 
 PHPAPI char *_php_stream_get_line(php_stream *stream, char *buf, size_t maxlen, size_t *returned_len);
 #define php_stream_gets(stream, buf, maxlen)	_php_stream_get_line((stream), (buf), (maxlen), NULL)
@@ -448,6 +447,14 @@ END_EXTERN_C()
 /* Enable/disable blocking reads on anonymous pipes on Windows. */
 #define PHP_STREAM_OPTION_PIPE_BLOCKING 13
 
+/* Stream can support fsync operation */
+#define PHP_STREAM_OPTION_SYNC_API		14
+#define PHP_STREAM_SYNC_SUPPORTED	0
+#define PHP_STREAM_SYNC_FSYNC 1
+
+#define php_stream_sync_supported(stream)	(_php_stream_set_option((stream), PHP_STREAM_OPTION_SYNC_API, PHP_STREAM_SYNC_SUPPORTED, NULL) == PHP_STREAM_OPTION_RETURN_OK ? 1 : 0)
+
+
 #define PHP_STREAM_OPTION_RETURN_OK			 0 /* option set OK */
 #define PHP_STREAM_OPTION_RETURN_ERR		-1 /* problem setting option */
 #define PHP_STREAM_OPTION_RETURN_NOTIMPL	-2 /* underlying stream does not implement; streams can handle it instead */
diff --git a/main/streams/glob_wrapper.c b/main/streams/glob_wrapper.c
index b1b5fd96d095..212d905e1609 100644
--- a/main/streams/glob_wrapper.c
+++ b/main/streams/glob_wrapper.c
@@ -190,8 +190,7 @@ const php_stream_ops  php_glob_stream_ops = {
 	php_glob_stream_rewind,
 	NULL, /* cast */
 	NULL, /* stat */
-	NULL,  /* set_option */
-	NULL
+	NULL  /* set_option */
 };
 
  /* {{{ php_glob_stream_opener */
diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index 7cd9eccbf008..234b77c52e46 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -520,7 +520,6 @@ static int php_stdiop_close(php_stream *stream, int close_handle)
 	return ret;
 }
 
-//dwg
 static int php_stdiop_sync(php_stream *stream)
 {
 	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
@@ -534,7 +533,7 @@ static int php_stdiop_sync(php_stream *stream)
 		    return fsync(fileno(data->file));
 		}
 	}
-	return ret;	
+	return ret;
 }
 
 static int php_stdiop_flush(php_stream *stream)
@@ -902,6 +901,14 @@ static int php_stdiop_set_option(php_stream *stream, int option, int value, void
 #endif
 			return PHP_STREAM_OPTION_RETURN_NOTIMPL;
 
+		case PHP_STREAM_OPTION_SYNC_API:
+			switch (value) {
+				case PHP_STREAM_SYNC_SUPPORTED:
+					return fd == -1 ? PHP_STREAM_OPTION_RETURN_ERR : PHP_STREAM_OPTION_RETURN_OK;
+				case PHP_STREAM_SYNC_FSYNC:
+				    return php_stdiop_sync(stream) == 0 ? PHP_STREAM_OPTION_RETURN_OK : PHP_STREAM_OPTION_RETURN_ERR;
+			}
+
 		case PHP_STREAM_OPTION_TRUNCATE_API:
 			switch (value) {
 				case PHP_STREAM_TRUNCATE_SUPPORTED:
@@ -979,8 +986,7 @@ PHPAPI php_stream_ops	php_stream_stdio_ops = {
 	php_stdiop_seek,
 	php_stdiop_cast,
 	php_stdiop_stat,
-	php_stdiop_set_option,
-	php_stdiop_sync,
+	php_stdiop_set_option
 };
 /* }}} */
 
diff --git a/main/streams/streams.c b/main/streams/streams.c
index 2ae6d5989818..efcebad002fa 100644
--- a/main/streams/streams.c
+++ b/main/streams/streams.c
@@ -1224,15 +1224,6 @@ static ssize_t _php_stream_write_filtered(php_stream *stream, const char *buf, s
 	return consumed;
 }
 
-PHPAPI int _php_stream_sync(php_stream *stream)
-{
-	int ret = 0;
-	if (stream->ops->sync) {
-		ret = stream->ops->sync(stream);
-	}
-	return ret;
-}
-
 PHPAPI int _php_stream_flush(php_stream *stream, int closing)
 {
 	int ret = 0;
@@ -1415,6 +1406,11 @@ PHPAPI int _php_stream_set_option(php_stream *stream, int option, int value, voi
 	return ret;
 }
 
+PHPAPI int _php_stream_sync(php_stream *stream)
+{
+	return php_stream_set_option(stream, PHP_STREAM_OPTION_SYNC_API, PHP_STREAM_SYNC_FSYNC, NULL);
+}
+
 PHPAPI int _php_stream_truncate_set_size(php_stream *stream, size_t newsize)
 {
 	return php_stream_set_option(stream, PHP_STREAM_OPTION_TRUNCATE_API, PHP_STREAM_TRUNCATE_SET_SIZE, &newsize);

From b8a54b1d23461ea6c863d2fdf4297b8c4d911181 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sat, 30 Jan 2021 16:06:06 +0000
Subject: [PATCH 04/18] fix typo on fflush condition

---
 main/streams/plain_wrapper.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index 234b77c52e46..1ed57f45a29d 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -529,7 +529,7 @@ static int php_stdiop_sync(php_stream *stream)
 
 	if (data->file) {
 		ret = fflush(data->file);
-		if (ret != 0) {
+		if (ret == 0) {
 		    return fsync(fileno(data->file));
 		}
 	}

From 400e4eeb10e1d07ef280c0ce31e8cfc3026c179e Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sat, 30 Jan 2021 17:34:11 +0000
Subject: [PATCH 05/18] added basic tests

---
 ext/standard/tests/file/fsync.phpt | 64 ++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 ext/standard/tests/file/fsync.phpt

diff --git a/ext/standard/tests/file/fsync.phpt b/ext/standard/tests/file/fsync.phpt
new file mode 100644
index 000000000000..f839999f0613
--- /dev/null
+++ b/ext/standard/tests/file/fsync.phpt
@@ -0,0 +1,64 @@
+--TEST--
+Test fsync() function: basic functionality
+--FILE--
+<?php
+
+echo "*** Testing fsync(): writing to a file and reading the contents ***\n";
+$data = <<<EOD
+first line of string
+second line of string
+third line of string
+EOD;
+
+$file_path = __DIR__;
+$filename = "$file_path/fsync_basic.tmp";
+
+// opening a file
+$file_handle = fopen($filename, "w");
+if($file_handle == false)
+  exit("Error:failed to open file $filename");
+
+if(substr(PHP_OS, 0, 3) == "WIN")  {
+    $data = str_replace("\r",'', $data);
+}
+
+// writing data to the file
+var_dump( fwrite($file_handle, $data) );
+var_dump( fsync($file_handle) );
+var_dump( readfile($filename) );
+
+echo "\n*** Testing fsync(): for return type ***\n";
+$return_value = fsync($file_handle);
+var_dump( is_bool($return_value) );
+fclose($file_handle);
+
+echo "\n*** Testing fsync(): for non-file stream ***\n";
+$file_handle = fopen("php://memory", "w");
+$return_value = fsync($file_handle);
+var_dump( ($return_value) );
+fclose($file_handle);
+
+echo "\n*** Done ***";
+?>
+--CLEAN--
+<?php
+$file_path = __DIR__;
+$filename = "$file_path/fsync_basic.tmp";
+unlink($filename);
+?>
+--EXPECT--
+*** Testing fsync(): writing to a file and reading the contents ***
+int(63)
+bool(true)
+first line of string
+second line of string
+third line of stringint(63)
+
+*** Testing fsync(): for return type ***
+bool(true)
+
+*** Testing fsync(): for non-file stream ***
+Warning: fsync(): Can't fsync this stream!
+bool(false)
+
+*** Done ***

From 55ecd46dca9ab31e77a6a51bd7e4dfc88692ca86 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sat, 30 Jan 2021 17:56:26 +0000
Subject: [PATCH 06/18] update test for warning format

---
 ext/standard/tests/file/fsync.phpt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ext/standard/tests/file/fsync.phpt b/ext/standard/tests/file/fsync.phpt
index f839999f0613..4718978dd31e 100644
--- a/ext/standard/tests/file/fsync.phpt
+++ b/ext/standard/tests/file/fsync.phpt
@@ -46,7 +46,7 @@ $file_path = __DIR__;
 $filename = "$file_path/fsync_basic.tmp";
 unlink($filename);
 ?>
---EXPECT--
+--EXPECTF--
 *** Testing fsync(): writing to a file and reading the contents ***
 int(63)
 bool(true)
@@ -58,7 +58,7 @@ third line of stringint(63)
 bool(true)
 
 *** Testing fsync(): for non-file stream ***
-Warning: fsync(): Can't fsync this stream!
+Warning: fsync(): Can't fsync this stream! in %s on line %d
 bool(false)
 
 *** Done ***

From b8a2a29dddd00bd6357526fb376955da5c8fb4da Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sat, 30 Jan 2021 18:17:41 +0000
Subject: [PATCH 07/18] fix test typo: missing new line causing test failure

---
 ext/standard/tests/file/fsync.phpt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/ext/standard/tests/file/fsync.phpt b/ext/standard/tests/file/fsync.phpt
index 4718978dd31e..3f7a19e59bb1 100644
--- a/ext/standard/tests/file/fsync.phpt
+++ b/ext/standard/tests/file/fsync.phpt
@@ -58,6 +58,7 @@ third line of stringint(63)
 bool(true)
 
 *** Testing fsync(): for non-file stream ***
+
 Warning: fsync(): Can't fsync this stream! in %s on line %d
 bool(false)
 

From c4b7d5d7ea38010426e2bd74d5674316e876956b Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sat, 30 Jan 2021 18:57:19 +0000
Subject: [PATCH 08/18] remove manual changes to generated arginfo

---
 ext/standard/basic_functions_arginfo.h | 2 --
 1 file changed, 2 deletions(-)

diff --git a/ext/standard/basic_functions_arginfo.h b/ext/standard/basic_functions_arginfo.h
index 1c67d5545f0f..5eafa59b50bd 100644
--- a/ext/standard/basic_functions_arginfo.h
+++ b/ext/standard/basic_functions_arginfo.h
@@ -2560,7 +2560,6 @@ ZEND_FUNCTION(fstat);
 ZEND_FUNCTION(fseek);
 ZEND_FUNCTION(ftell);
 ZEND_FUNCTION(fflush);
-ZEND_FUNCTION(fsync);
 ZEND_FUNCTION(fwrite);
 ZEND_FUNCTION(mkdir);
 ZEND_FUNCTION(rename);
@@ -3198,7 +3197,6 @@ static const zend_function_entry ext_functions[] = {
 	ZEND_FE(fseek, arginfo_fseek)
 	ZEND_FE(ftell, arginfo_ftell)
 	ZEND_FE(fflush, arginfo_fflush)
-	ZEND_FE(fsync, arginfo_fflush)
 	ZEND_FE(fwrite, arginfo_fwrite)
 	ZEND_FALIAS(fputs, fwrite, arginfo_fputs)
 	ZEND_FE(mkdir, arginfo_mkdir)

From 344f380e3f5e6023373602e6407bb95fba2e6ccd Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sat, 30 Jan 2021 19:16:03 +0000
Subject: [PATCH 09/18] regenerated args header

---
 ext/standard/basic_functions_arginfo.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ext/standard/basic_functions_arginfo.h b/ext/standard/basic_functions_arginfo.h
index 5eafa59b50bd..13dbf66ffa66 100644
--- a/ext/standard/basic_functions_arginfo.h
+++ b/ext/standard/basic_functions_arginfo.h
@@ -1,5 +1,5 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: 7540039937587f05584660bc1a1a8a80aa5ccbd1 */
+ * Stub hash: 10b34c3c2fc59b9b7d635c69604b4c3d5fd7b19b */
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_set_time_limit, 0, 1, _IS_BOOL, 0)
 	ZEND_ARG_TYPE_INFO(0, seconds, IS_LONG, 0)
@@ -1269,6 +1269,8 @@ ZEND_END_ARG_INFO()
 
 #define arginfo_fflush arginfo_rewind
 
+#define arginfo_fsync arginfo_rewind
+
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_MASK_EX(arginfo_fwrite, 0, 2, MAY_BE_LONG|MAY_BE_FALSE)
 	ZEND_ARG_INFO(0, stream)
 	ZEND_ARG_TYPE_INFO(0, data, IS_STRING, 0)
@@ -2560,6 +2562,7 @@ ZEND_FUNCTION(fstat);
 ZEND_FUNCTION(fseek);
 ZEND_FUNCTION(ftell);
 ZEND_FUNCTION(fflush);
+ZEND_FUNCTION(fsync);
 ZEND_FUNCTION(fwrite);
 ZEND_FUNCTION(mkdir);
 ZEND_FUNCTION(rename);
@@ -3197,6 +3200,7 @@ static const zend_function_entry ext_functions[] = {
 	ZEND_FE(fseek, arginfo_fseek)
 	ZEND_FE(ftell, arginfo_ftell)
 	ZEND_FE(fflush, arginfo_fflush)
+	ZEND_FE(fsync, arginfo_fsync)
 	ZEND_FE(fwrite, arginfo_fwrite)
 	ZEND_FALIAS(fputs, fwrite, arginfo_fputs)
 	ZEND_FE(mkdir, arginfo_mkdir)

From f63410cc8c94fd36f499a1d2fd666e9d4b80f8bc Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sun, 31 Jan 2021 19:15:53 +0000
Subject: [PATCH 10/18] improve implementation of fsync PHP function

---
 main/streams/plain_wrapper.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index 1ed57f45a29d..d27300003b0e 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -523,17 +523,20 @@ static int php_stdiop_close(php_stream *stream, int close_handle)
 static int php_stdiop_sync(php_stream *stream)
 {
 	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
-	int ret = 0;
+	FILE *fp;
 
-	assert(data != NULL);
+	if (php_stream_cast(stream, PHP_STREAM_AS_STDIO, (void**)&fp, REPORT_ERRORS) == FAILURE) {
+		return 1;
+	}
 
-	if (data->file) {
-		ret = fflush(data->file);
-		if (ret == 0) {
-		    return fsync(fileno(data->file));
-		}
+	if (php_stdiop_flush(stream) == 0) {
+		#ifdef PHP_WIN32
+		return _commit(fileno(fp));
+		#else
+		return fsync(fileno(fp));
+		#endif
 	}
-	return ret;
+	return 1;
 }
 
 static int php_stdiop_flush(php_stream *stream)

From e018a8e915a8e359cee340d2e4f6104323bd9434 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sun, 31 Jan 2021 21:20:48 +0000
Subject: [PATCH 11/18] cleanup of stdiop fsync

---
 main/streams/plain_wrapper.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index d27300003b0e..afc36d087df6 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -524,19 +524,21 @@ static int php_stdiop_sync(php_stream *stream)
 {
 	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
 	FILE *fp;
+	int fd;
 
 	if (php_stream_cast(stream, PHP_STREAM_AS_STDIO, (void**)&fp, REPORT_ERRORS) == FAILURE) {
-		return 1;
+		return -1;
 	}
 
 	if (php_stdiop_flush(stream) == 0) {
+		PHP_STDIOP_GET_FD(fd, data);
 		#ifdef PHP_WIN32
-		return _commit(fileno(fp));
+		return _commit(fd);
 		#else
-		return fsync(fileno(fp));
+		return fsync(fd);
 		#endif
 	}
-	return 1;
+	return -1;
 }
 
 static int php_stdiop_flush(php_stream *stream)

From 994aa8cf28bbee95042d63ad16f937f7a89a4e96 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Sun, 31 Jan 2021 22:10:30 +0000
Subject: [PATCH 12/18] fix ordering for gcc

---
 main/streams/plain_wrapper.c | 35 ++++++++++++++++++-----------------
 1 file changed, 18 insertions(+), 17 deletions(-)

diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index afc36d087df6..8d45ef3ed9ed 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -520,6 +520,24 @@ static int php_stdiop_close(php_stream *stream, int close_handle)
 	return ret;
 }
 
+static int php_stdiop_flush(php_stream *stream)
+{
+	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
+
+	assert(data != NULL);
+
+	/*
+	 * stdio buffers data in user land. By calling fflush(3), this
+	 * data is send to the kernel using write(2). fsync'ing is
+	 * something completely different.
+	 */
+	if (data->file) {
+		return fflush(data->file);
+	}
+	return 0;
+}
+
+
 static int php_stdiop_sync(php_stream *stream)
 {
 	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
@@ -541,23 +559,6 @@ static int php_stdiop_sync(php_stream *stream)
 	return -1;
 }
 
-static int php_stdiop_flush(php_stream *stream)
-{
-	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
-
-	assert(data != NULL);
-
-	/*
-	 * stdio buffers data in user land. By calling fflush(3), this
-	 * data is send to the kernel using write(2). fsync'ing is
-	 * something completely different.
-	 */
-	if (data->file) {
-		return fflush(data->file);
-	}
-	return 0;
-}
-
 static int php_stdiop_seek(php_stream *stream, zend_off_t offset, int whence, zend_off_t *newoffset)
 {
 	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;

From 8ada0d9865e6640887299e6662a65ead38b33937 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Mon, 1 Feb 2021 16:38:38 +0000
Subject: [PATCH 13/18] add fdatasync

---
 ext/standard/basic_functions.stub.php  |  3 +++
 ext/standard/basic_functions_arginfo.h |  6 +++++-
 ext/standard/file.c                    | 30 +++++++++++++++++++++++++-
 main/php_streams.h                     |  5 +++--
 main/streams/plain_wrapper.c           | 18 ++++++++++------
 main/streams/streams.c                 |  8 +++++--
 6 files changed, 57 insertions(+), 13 deletions(-)

diff --git a/ext/standard/basic_functions.stub.php b/ext/standard/basic_functions.stub.php
index 0e17f444bca3..9edc99525bd8 100755
--- a/ext/standard/basic_functions.stub.php
+++ b/ext/standard/basic_functions.stub.php
@@ -826,6 +826,9 @@ function fflush($stream): bool {}
 /** @param resource $stream */
 function fsync($stream): bool {}
 
+/** @param resource $stream */
+function fdatasync($stream): bool {}
+
 /** @param resource $stream */
 function fwrite($stream, string $data, ?int $length = null): int|false {}
 
diff --git a/ext/standard/basic_functions_arginfo.h b/ext/standard/basic_functions_arginfo.h
index 13dbf66ffa66..caa381581032 100644
--- a/ext/standard/basic_functions_arginfo.h
+++ b/ext/standard/basic_functions_arginfo.h
@@ -1,5 +1,5 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: 10b34c3c2fc59b9b7d635c69604b4c3d5fd7b19b */
+ * Stub hash: eb45395f5358feea888625ca491c75b677cfe51d */
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_set_time_limit, 0, 1, _IS_BOOL, 0)
 	ZEND_ARG_TYPE_INFO(0, seconds, IS_LONG, 0)
@@ -1271,6 +1271,8 @@ ZEND_END_ARG_INFO()
 
 #define arginfo_fsync arginfo_rewind
 
+#define arginfo_fdatasync arginfo_rewind
+
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_MASK_EX(arginfo_fwrite, 0, 2, MAY_BE_LONG|MAY_BE_FALSE)
 	ZEND_ARG_INFO(0, stream)
 	ZEND_ARG_TYPE_INFO(0, data, IS_STRING, 0)
@@ -2563,6 +2565,7 @@ ZEND_FUNCTION(fseek);
 ZEND_FUNCTION(ftell);
 ZEND_FUNCTION(fflush);
 ZEND_FUNCTION(fsync);
+ZEND_FUNCTION(fdatasync);
 ZEND_FUNCTION(fwrite);
 ZEND_FUNCTION(mkdir);
 ZEND_FUNCTION(rename);
@@ -3201,6 +3204,7 @@ static const zend_function_entry ext_functions[] = {
 	ZEND_FE(ftell, arginfo_ftell)
 	ZEND_FE(fflush, arginfo_fflush)
 	ZEND_FE(fsync, arginfo_fsync)
+	ZEND_FE(fdatasync, arginfo_fdatasync)
 	ZEND_FE(fwrite, arginfo_fwrite)
 	ZEND_FALIAS(fputs, fwrite, arginfo_fputs)
 	ZEND_FE(mkdir, arginfo_mkdir)
diff --git a/ext/standard/file.c b/ext/standard/file.c
index aeddb1993054..32c51f9051d7 100644
--- a/ext/standard/file.c
+++ b/ext/standard/file.c
@@ -1485,7 +1485,7 @@ PHP_FUNCTION(fsync)
 		RETURN_FALSE;
 	}
 
-	ret = php_stream_sync(stream);
+	ret = php_stream_sync(stream, 0);
 	if (ret) {
 		RETURN_FALSE;
 	}
@@ -1494,6 +1494,34 @@ PHP_FUNCTION(fsync)
 }
 /* }}} */
 
+/* {{{ Sync file data only to storage. Similar to fsync but does not flush modified metadata. POSIX only, aliased to fsync on Win32. */
+PHP_FUNCTION(fdatasync)
+{
+	zval *res;
+	int ret;
+	php_stream *stream;
+
+	ZEND_PARSE_PARAMETERS_START(1, 1)
+		Z_PARAM_RESOURCE(res)
+	ZEND_PARSE_PARAMETERS_END();
+
+	PHP_STREAM_TO_ZVAL(stream, res);
+
+	if (!php_stream_sync_supported(stream)) {
+		php_error_docref(NULL, E_WARNING, "Can't fsync this stream!");
+		RETURN_FALSE;
+	}
+
+	ret = php_stream_sync(stream, 1);
+	if (ret) {
+		RETURN_FALSE;
+	}
+	RETURN_TRUE;
+
+}
+/* }}} */
+
+
 
 /* {{{ Truncate file to 'size' length */
 PHP_FUNCTION(ftruncate)
diff --git a/main/php_streams.h b/main/php_streams.h
index 1437f01d2c62..0bae682cedb0 100644
--- a/main/php_streams.h
+++ b/main/php_streams.h
@@ -336,8 +336,8 @@ PHPAPI int _php_stream_putc(php_stream *stream, int c);
 PHPAPI int _php_stream_flush(php_stream *stream, int closing);
 #define php_stream_flush(stream)	_php_stream_flush((stream), 0)
 
-PHPAPI int _php_stream_sync(php_stream *stream);
-#define php_stream_sync(stream)	    _php_stream_sync((stream))
+PHPAPI int _php_stream_sync(php_stream *stream, int dataonly);
+#define php_stream_sync(stream, d)	    _php_stream_sync((stream), (d))
 
 PHPAPI char *_php_stream_get_line(php_stream *stream, char *buf, size_t maxlen, size_t *returned_len);
 #define php_stream_gets(stream, buf, maxlen)	_php_stream_get_line((stream), (buf), (maxlen), NULL)
@@ -451,6 +451,7 @@ END_EXTERN_C()
 #define PHP_STREAM_OPTION_SYNC_API		14
 #define PHP_STREAM_SYNC_SUPPORTED	0
 #define PHP_STREAM_SYNC_FSYNC 1
+#define PHP_STREAM_SYNC_FDSYNC 2
 
 #define php_stream_sync_supported(stream)	(_php_stream_set_option((stream), PHP_STREAM_OPTION_SYNC_API, PHP_STREAM_SYNC_SUPPORTED, NULL) == PHP_STREAM_OPTION_RETURN_OK ? 1 : 0)
 
diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index 8d45ef3ed9ed..8f93021ba0d1 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -54,6 +54,8 @@ extern int php_get_gid_by_name(const char *name, gid_t *gid);
 
 #if defined(PHP_WIN32)
 # define PLAIN_WRAP_BUF_SIZE(st) (((st) > UINT_MAX) ? UINT_MAX : (unsigned int)(st))
+#define fsync _commit
+#define fdatasync fsync
 #else
 # define PLAIN_WRAP_BUF_SIZE(st) (st)
 #endif
@@ -538,7 +540,7 @@ static int php_stdiop_flush(php_stream *stream)
 }
 
 
-static int php_stdiop_sync(php_stream *stream)
+static int php_stdiop_sync(php_stream *stream, int dataonly)
 {
 	php_stdio_stream_data *data = (php_stdio_stream_data*)stream->abstract;
 	FILE *fp;
@@ -550,11 +552,11 @@ static int php_stdiop_sync(php_stream *stream)
 
 	if (php_stdiop_flush(stream) == 0) {
 		PHP_STDIOP_GET_FD(fd, data);
-		#ifdef PHP_WIN32
-		return _commit(fd);
-		#else
-		return fsync(fd);
-		#endif
+		if (dataonly) {
+			return fdatasync(fd);
+		} else {
+			return fsync(fd);
+		}
 	}
 	return -1;
 }
@@ -912,7 +914,9 @@ static int php_stdiop_set_option(php_stream *stream, int option, int value, void
 				case PHP_STREAM_SYNC_SUPPORTED:
 					return fd == -1 ? PHP_STREAM_OPTION_RETURN_ERR : PHP_STREAM_OPTION_RETURN_OK;
 				case PHP_STREAM_SYNC_FSYNC:
-				    return php_stdiop_sync(stream) == 0 ? PHP_STREAM_OPTION_RETURN_OK : PHP_STREAM_OPTION_RETURN_ERR;
+				    return php_stdiop_sync(stream, 0) == 0 ? PHP_STREAM_OPTION_RETURN_OK : PHP_STREAM_OPTION_RETURN_ERR;
+				case PHP_STREAM_SYNC_FDSYNC:
+				    return php_stdiop_sync(stream, 1) == 0 ? PHP_STREAM_OPTION_RETURN_OK : PHP_STREAM_OPTION_RETURN_ERR;
 			}
 
 		case PHP_STREAM_OPTION_TRUNCATE_API:
diff --git a/main/streams/streams.c b/main/streams/streams.c
index efcebad002fa..1be0ad0bb4a4 100644
--- a/main/streams/streams.c
+++ b/main/streams/streams.c
@@ -1406,9 +1406,13 @@ PHPAPI int _php_stream_set_option(php_stream *stream, int option, int value, voi
 	return ret;
 }
 
-PHPAPI int _php_stream_sync(php_stream *stream)
+PHPAPI int _php_stream_sync(php_stream *stream, int dataonly)
 {
-	return php_stream_set_option(stream, PHP_STREAM_OPTION_SYNC_API, PHP_STREAM_SYNC_FSYNC, NULL);
+	int op = PHP_STREAM_SYNC_FSYNC;
+	if (dataonly) {
+		op = PHP_STREAM_SYNC_FDSYNC;
+	}
+	return php_stream_set_option(stream, PHP_STREAM_OPTION_SYNC_API, op, NULL);
 }
 
 PHPAPI int _php_stream_truncate_set_size(php_stream *stream, size_t newsize)

From e7f84289684d3b439bb23124c00980bb7ad8a026 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Mon, 1 Feb 2021 17:26:30 +0000
Subject: [PATCH 14/18] add ro tests and fdatasync tests

---
 ext/standard/tests/file/fdatasync.phpt | 73 ++++++++++++++++++++++++++
 ext/standard/tests/file/fsync.phpt     |  8 +++
 2 files changed, 81 insertions(+)
 create mode 100644 ext/standard/tests/file/fdatasync.phpt

diff --git a/ext/standard/tests/file/fdatasync.phpt b/ext/standard/tests/file/fdatasync.phpt
new file mode 100644
index 000000000000..29e33a56a316
--- /dev/null
+++ b/ext/standard/tests/file/fdatasync.phpt
@@ -0,0 +1,73 @@
+--TEST--
+Test fdatasync() function: basic functionality
+--FILE--
+<?php
+
+echo "*** Testing fdatasync(): writing to a file and reading the contents ***\n";
+$data = <<<EOD
+first line of string
+second line of string
+third line of string
+EOD;
+
+$file_path = __DIR__;
+$filename = "$file_path/fdatasync_basic.tmp";
+
+// opening a file
+$file_handle = fopen($filename, "w");
+if($file_handle == false)
+  exit("Error:failed to open file $filename");
+
+if(substr(PHP_OS, 0, 3) == "WIN")  {
+    $data = str_replace("\r",'', $data);
+}
+
+// writing data to the file
+var_dump( fwrite($file_handle, $data) );
+var_dump( fdatasync($file_handle) );
+var_dump( readfile($filename) );
+
+echo "\n*** Testing fdatasync(): for return type ***\n";
+$return_value = fdatasync($file_handle);
+var_dump( is_bool($return_value) );
+fclose($file_handle);
+
+echo "\n*** Testing fdatasync(): attempting to sync read-only file ***\n";
+$file_handle = fopen($filename, "r");
+var_dump(fdatasync($file_handle));
+fclose($file_handle);
+
+echo "\n*** Testing fdatasync(): for non-file stream ***\n";
+$file_handle = fopen("php://memory", "w");
+$return_value = fdatasync($file_handle);
+var_dump( ($return_value) );
+fclose($file_handle);
+
+echo "\n*** Done ***";
+?>
+--CLEAN--
+<?php
+$file_path = __DIR__;
+$filename = "$file_path/fdatasync_basic.tmp";
+unlink($filename);
+?>
+--EXPECTF--
+*** Testing fdatasync(): writing to a file and reading the contents ***
+int(63)
+bool(true)
+first line of string
+second line of string
+third line of stringint(63)
+
+*** Testing fdatasync(): for return type ***
+bool(true)
+
+*** Testing fdatasync(): attempting to sync read-only file ***
+bool(false)
+
+*** Testing fdatasync(): for non-file stream ***
+
+Warning: fdatasync(): Can't fsync this stream! in %s on line %d
+bool(false)
+
+*** Done ***
diff --git a/ext/standard/tests/file/fsync.phpt b/ext/standard/tests/file/fsync.phpt
index 3f7a19e59bb1..f38b84d1b6f8 100644
--- a/ext/standard/tests/file/fsync.phpt
+++ b/ext/standard/tests/file/fsync.phpt
@@ -32,6 +32,11 @@ $return_value = fsync($file_handle);
 var_dump( is_bool($return_value) );
 fclose($file_handle);
 
+echo "\n*** Testing fsync(): attempting to sync read-only file ***\n";
+$file_handle = fopen($filename, "r");
+var_dump(fsync($file_handle));
+fclose($file_handle);
+
 echo "\n*** Testing fsync(): for non-file stream ***\n";
 $file_handle = fopen("php://memory", "w");
 $return_value = fsync($file_handle);
@@ -57,6 +62,9 @@ third line of stringint(63)
 *** Testing fsync(): for return type ***
 bool(true)
 
+*** Testing fsync(): attempting to sync read-only file ***
+bool(false)
+
 *** Testing fsync(): for non-file stream ***
 
 Warning: fsync(): Can't fsync this stream! in %s on line %d

From 1f4cc8ed9397da68fa5cbae0f719e8cdf1cc3692 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Tue, 2 Feb 2021 11:45:33 +0000
Subject: [PATCH 15/18] update tests; replace test fsync ro failure on posix

---
 ext/standard/tests/file/fdatasync.phpt | 6 +++---
 ext/standard/tests/file/fsync.phpt     | 6 +++---
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/ext/standard/tests/file/fdatasync.phpt b/ext/standard/tests/file/fdatasync.phpt
index 29e33a56a316..7ce0049ae1a5 100644
--- a/ext/standard/tests/file/fdatasync.phpt
+++ b/ext/standard/tests/file/fdatasync.phpt
@@ -32,8 +32,8 @@ $return_value = fdatasync($file_handle);
 var_dump( is_bool($return_value) );
 fclose($file_handle);
 
-echo "\n*** Testing fdatasync(): attempting to sync read-only file ***\n";
-$file_handle = fopen($filename, "r");
+echo "\n*** Testing fdatasync(): attempting to sync stdin ***\n";
+$file_handle = fopen("php://stdin", "w");
 var_dump(fdatasync($file_handle));
 fclose($file_handle);
 
@@ -62,7 +62,7 @@ third line of stringint(63)
 *** Testing fdatasync(): for return type ***
 bool(true)
 
-*** Testing fdatasync(): attempting to sync read-only file ***
+*** Testing fdatasync(): attempting to sync stdin ***
 bool(false)
 
 *** Testing fdatasync(): for non-file stream ***
diff --git a/ext/standard/tests/file/fsync.phpt b/ext/standard/tests/file/fsync.phpt
index f38b84d1b6f8..a841ecd4cd26 100644
--- a/ext/standard/tests/file/fsync.phpt
+++ b/ext/standard/tests/file/fsync.phpt
@@ -32,8 +32,8 @@ $return_value = fsync($file_handle);
 var_dump( is_bool($return_value) );
 fclose($file_handle);
 
-echo "\n*** Testing fsync(): attempting to sync read-only file ***\n";
-$file_handle = fopen($filename, "r");
+echo "\n*** Testing fsync(): attempting to sync stdin ***\n";
+$file_handle = fopen("php://stdin", "w");
 var_dump(fsync($file_handle));
 fclose($file_handle);
 
@@ -62,7 +62,7 @@ third line of stringint(63)
 *** Testing fsync(): for return type ***
 bool(true)
 
-*** Testing fsync(): attempting to sync read-only file ***
+*** Testing fsync(): attempting to sync stdin ***
 bool(false)
 
 *** Testing fsync(): for non-file stream ***

From a9b2ee532368003602325710dc7f868abaeec157 Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Wed, 3 Feb 2021 10:56:52 +0000
Subject: [PATCH 16/18] replace spaced indent with tab

---
 main/streams/plain_wrapper.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index 8f93021ba0d1..f72a719f65c4 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -914,9 +914,9 @@ static int php_stdiop_set_option(php_stream *stream, int option, int value, void
 				case PHP_STREAM_SYNC_SUPPORTED:
 					return fd == -1 ? PHP_STREAM_OPTION_RETURN_ERR : PHP_STREAM_OPTION_RETURN_OK;
 				case PHP_STREAM_SYNC_FSYNC:
-				    return php_stdiop_sync(stream, 0) == 0 ? PHP_STREAM_OPTION_RETURN_OK : PHP_STREAM_OPTION_RETURN_ERR;
+					return php_stdiop_sync(stream, 0) == 0 ? PHP_STREAM_OPTION_RETURN_OK : PHP_STREAM_OPTION_RETURN_ERR;
 				case PHP_STREAM_SYNC_FDSYNC:
-				    return php_stdiop_sync(stream, 1) == 0 ? PHP_STREAM_OPTION_RETURN_OK : PHP_STREAM_OPTION_RETURN_ERR;
+					return php_stdiop_sync(stream, 1) == 0 ? PHP_STREAM_OPTION_RETURN_OK : PHP_STREAM_OPTION_RETURN_ERR;
 			}
 
 		case PHP_STREAM_OPTION_TRUNCATE_API:

From 02739dff5d2f02e1d5b3b8cbb26c2cfdadaae97a Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Wed, 24 Mar 2021 22:34:38 +0000
Subject: [PATCH 17/18] address review comments

---
 ext/standard/file.c                    | 14 ++------------
 ext/standard/file.h                    |  1 -
 ext/standard/tests/file/fdatasync.phpt |  2 +-
 ext/standard/tests/file/fsync.phpt     |  2 +-
 main/php_streams.h                     |  2 +-
 main/streams/streams.c                 |  4 ++--
 6 files changed, 7 insertions(+), 18 deletions(-)

diff --git a/ext/standard/file.c b/ext/standard/file.c
index 54ca15500c07..aa1fde7fd116 100644
--- a/ext/standard/file.c
+++ b/ext/standard/file.c
@@ -1481,12 +1481,7 @@ PHP_FUNCTION(fsync)
 		RETURN_FALSE;
 	}
 
-	ret = php_stream_sync(stream, 0);
-	if (ret) {
-		RETURN_FALSE;
-	}
-	RETURN_TRUE;
-
+    RETURN_BOOL(php_stream_sync(stream, /* data_only */ 0) == 0);
 }
 /* }}} */
 
@@ -1508,12 +1503,7 @@ PHP_FUNCTION(fdatasync)
 		RETURN_FALSE;
 	}
 
-	ret = php_stream_sync(stream, 1);
-	if (ret) {
-		RETURN_FALSE;
-	}
-	RETURN_TRUE;
-
+    RETURN_BOOL(php_stream_sync(stream, /* data_only */ 1) == 0);
 }
 /* }}} */
 
diff --git a/ext/standard/file.h b/ext/standard/file.h
index 9cf007a0f062..f9d153a52a5d 100644
--- a/ext/standard/file.h
+++ b/ext/standard/file.h
@@ -29,7 +29,6 @@ PHPAPI PHP_FUNCTION(fgetc);
 PHPAPI PHP_FUNCTION(fgets);
 PHPAPI PHP_FUNCTION(fwrite);
 PHPAPI PHP_FUNCTION(fflush);
-PHPAPI PHP_FUNCTION(fsync);
 PHPAPI PHP_FUNCTION(rewind);
 PHPAPI PHP_FUNCTION(ftell);
 PHPAPI PHP_FUNCTION(fseek);
diff --git a/ext/standard/tests/file/fdatasync.phpt b/ext/standard/tests/file/fdatasync.phpt
index 7ce0049ae1a5..235669a9943f 100644
--- a/ext/standard/tests/file/fdatasync.phpt
+++ b/ext/standard/tests/file/fdatasync.phpt
@@ -18,7 +18,7 @@ $file_handle = fopen($filename, "w");
 if($file_handle == false)
   exit("Error:failed to open file $filename");
 
-if(substr(PHP_OS, 0, 3) == "WIN")  {
+if(PHP_OS_FAMILY == 'Windows')  {
     $data = str_replace("\r",'', $data);
 }
 
diff --git a/ext/standard/tests/file/fsync.phpt b/ext/standard/tests/file/fsync.phpt
index a841ecd4cd26..7a036a55d4d0 100644
--- a/ext/standard/tests/file/fsync.phpt
+++ b/ext/standard/tests/file/fsync.phpt
@@ -18,7 +18,7 @@ $file_handle = fopen($filename, "w");
 if($file_handle == false)
   exit("Error:failed to open file $filename");
 
-if(substr(PHP_OS, 0, 3) == "WIN")  {
+if(PHP_OS_FAMILY == 'Windows')  {
     $data = str_replace("\r",'', $data);
 }
 
diff --git a/main/php_streams.h b/main/php_streams.h
index 794b8c6a3d49..ba1addd22160 100644
--- a/main/php_streams.h
+++ b/main/php_streams.h
@@ -336,7 +336,7 @@ PHPAPI int _php_stream_putc(php_stream *stream, int c);
 PHPAPI int _php_stream_flush(php_stream *stream, int closing);
 #define php_stream_flush(stream)	_php_stream_flush((stream), 0)
 
-PHPAPI int _php_stream_sync(php_stream *stream, int dataonly);
+PHPAPI int _php_stream_sync(php_stream *stream, bool data_only);
 #define php_stream_sync(stream, d)	    _php_stream_sync((stream), (d))
 
 PHPAPI char *_php_stream_get_line(php_stream *stream, char *buf, size_t maxlen, size_t *returned_len);
diff --git a/main/streams/streams.c b/main/streams/streams.c
index 4c292f2d6fd9..4965d671f474 100644
--- a/main/streams/streams.c
+++ b/main/streams/streams.c
@@ -1406,10 +1406,10 @@ PHPAPI int _php_stream_set_option(php_stream *stream, int option, int value, voi
 	return ret;
 }
 
-PHPAPI int _php_stream_sync(php_stream *stream, int dataonly)
+PHPAPI int _php_stream_sync(php_stream *stream, bool data_only)
 {
 	int op = PHP_STREAM_SYNC_FSYNC;
-	if (dataonly) {
+	if (data_only) {
 		op = PHP_STREAM_SYNC_FDSYNC;
 	}
 	return php_stream_set_option(stream, PHP_STREAM_OPTION_SYNC_API, op, NULL);

From 80cbc2930edbd24b8129174d507ad3dd6192a0db Mon Sep 17 00:00:00 2001
From: David Gebler <davidgebler@gmail.com>
Date: Wed, 24 Mar 2021 22:43:34 +0000
Subject: [PATCH 18/18] remove unused variable

---
 ext/standard/file.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/ext/standard/file.c b/ext/standard/file.c
index aa1fde7fd116..00dcd5c7b675 100644
--- a/ext/standard/file.c
+++ b/ext/standard/file.c
@@ -1467,7 +1467,6 @@ PHP_FUNCTION(unlink)
 PHP_FUNCTION(fsync)
 {
 	zval *res;
-	int ret;
 	php_stream *stream;
 
 	ZEND_PARSE_PARAMETERS_START(1, 1)
@@ -1489,7 +1488,6 @@ PHP_FUNCTION(fsync)
 PHP_FUNCTION(fdatasync)
 {
 	zval *res;
-	int ret;
 	php_stream *stream;
 
 	ZEND_PARSE_PARAMETERS_START(1, 1)