main/streams/streams: use copy_file_range() on Linux

configure.ac

@@ -364,6 +364,7 @@ PHP_CHECK_FUNC(socketpair, socket, network)
 PHP_CHECK_FUNC(htonl, socket, network)
 PHP_CHECK_FUNC(gethostname, nsl, network)
 PHP_CHECK_FUNC(gethostbyaddr, nsl, network)
+PHP_CHECK_FUNC(copy_file_range)
 PHP_CHECK_FUNC(dlopen, dl, root)
 PHP_CHECK_FUNC(dlsym, dl, root)
 if test "$ac_cv_func_dlopen" = "yes"; then

ext/standard/tests/file/stream_copy_to_stream.phpt

@@ -12,6 +12,8 @@ stream_filter_append($src, "string.rot13", STREAM_FILTER_READ);
 
 $dest = fopen($new_file, 'w');
 var_dump(stream_copy_to_stream($src, $dest, 0));
+var_dump(ftell($src));
+var_dump(ftell($dest));
 fclose($src); fclose($dest);
 
 var_dump(file_get_contents($new_file));
@@ -24,6 +26,8 @@ stream_filter_append($src, "string.rot13", STREAM_FILTER_READ);
 
 $dest = fopen($new_file, 'w');
 var_dump(stream_copy_to_stream($src, $dest, -1));
+var_dump(ftell($src));
+var_dump(ftell($dest));
 fclose($src); fclose($dest);
 if (WIN) {
   var_dump(str_replace("\r\n","\n", file_get_contents($new_file)));
@@ -39,6 +43,8 @@ stream_filter_append($src, "string.rot13", STREAM_FILTER_READ);
 
 $dest = fopen($new_file, 'w');
 var_dump(stream_copy_to_stream($src, $dest));
+var_dump(ftell($src));
+var_dump(ftell($dest));
 fclose($src); fclose($dest);
 
 if (WIN) {
@@ -54,6 +60,8 @@ $src = fopen($initial_file, 'r');
 
 $dest = fopen($new_file, 'w');
 var_dump(stream_copy_to_stream($src, $dest));
+var_dump(ftell($src));
+var_dump(ftell($dest));
 fclose($src); fclose($dest);
 
 if (WIN) {
@@ -69,6 +77,8 @@ $src = fopen($initial_file, 'r');
 
 $dest = fopen($new_file, 'w');
 var_dump(stream_copy_to_stream($src, $dest, 1000000));
+var_dump(ftell($src));
+var_dump(ftell($dest));
 fclose($src); fclose($dest);
 
 if (WIN) {
@@ -85,6 +95,8 @@ $src = fopen($initial_file, 'r');
 
 $dest = fopen($new_file, 'w');
 var_dump(stream_copy_to_stream($src, $dest, 10));
+var_dump(ftell($src));
+var_dump(ftell($dest));
 fclose($src); fclose($dest);
 
 if (WIN) {
@@ -100,6 +112,8 @@ $src = fopen($initial_file, 'r');
 
 $dest = fopen($new_file, 'w');
 var_dump(stream_copy_to_stream($src, $dest, -1));
+var_dump(ftell($src));
+var_dump(ftell($dest));
 fclose($src); fclose($dest);
 
 if (WIN) {
@@ -113,38 +127,52 @@ echo "Done\n";
 ?>
 --EXPECTF--
 int(0)
+int(0)
+int(0)
 string(0) ""
 int(%d)
+int(134)
+int(134)
 string(134) "Nabgure qnl
 Jura gur cnvaf bs yvsr jba'g one zl jnl
 V'yy oernx gurfr punvaf
 Gung ubyq zr qbja
 V'yy grne lbh qbja vagb zl cevingr uryy
 "
 int(%d)
+int(134)
+int(134)
 string(134) "Nabgure qnl
 Jura gur cnvaf bs yvsr jba'g one zl jnl
 V'yy oernx gurfr punvaf
 Gung ubyq zr qbja
 V'yy grne lbh qbja vagb zl cevingr uryy
 "
 int(%d)
+int(134)
+int(134)
 string(134) "Another day
 When the pains of life won't bar my way
 I'll break these chains
 That hold me down
 I'll tear you down into my private hell
 "
 int(%d)
+int(134)
+int(134)
 string(134) "Another day
 When the pains of life won't bar my way
 I'll break these chains
 That hold me down
 I'll tear you down into my private hell
 "
 int(%d)
+int(10)
+int(10)
 string(10) "Another da"
 int(%d)
+int(134)
+int(134)
 string(134) "Another day
 When the pains of life won't bar my way
 I'll break these chains

ext/standard/tests/file/stream_copy_to_stream_interleaved.phpt

@@ -0,0 +1,48 @@
+--TEST--
+stream_copy_to_stream() tests with interleaved read/write calls
+--FILE--
+<?php
+define('WIN', substr(PHP_OS, 0, 3) == 'WIN');
+
+$initial_file = __DIR__.'/bug38086.txt';
+$new_file = __DIR__.'/stream_copy_to_stream_interleaved.txt';
+
+$src = fopen($initial_file, 'r');
+
+$dest = fopen($new_file, 'w');
+
+var_dump(fread($src, 10));
+var_dump(fwrite($dest, "foo"));
+var_dump(stream_copy_to_stream($src, $dest, 10));
+var_dump(ftell($src));
+var_dump(ftell($dest));
+var_dump(fread($src, 10));
+var_dump(fwrite($dest, "bar"));
+var_dump(stream_copy_to_stream($src, $dest, 10));
+var_dump(ftell($src));
+var_dump(ftell($dest));
+fclose($src); fclose($dest);
+
+if (WIN) {
+  var_dump(str_replace("\r\n","\n", file_get_contents($new_file)));
+} else {
+  var_dump(file_get_contents($new_file));
+}
+unlink($new_file);
+
+echo "Done\n";
+?>
+--EXPECTF--
+string(10) "Another da"
+int(3)
+int(10)
+int(20)
+int(13)
+string(10) " pains of "
+int(3)
+int(10)
+int(40)
+int(26)
+string(26) "fooy
+When thebarlife won't"
+Done

main/streams/streams.c

@@ -1555,6 +1555,90 @@ PHPAPI zend_result _php_stream_copy_to_stream_ex(php_stream *src, php_stream *de
 		return SUCCESS;
 	}
 
+#ifdef HAVE_COPY_FILE_RANGE
+
+	/* TODO: on FreeBSD, copy_file_range() works only with the
+	   undocumented flag 0x01000000; until the problem is fixed
+	   properly, copy_file_range() is not used on FreeBSD */
+#ifndef __FreeBSD__
+	if (php_stream_is(src, PHP_STREAM_IS_STDIO) &&
+	    php_stream_is(dest, PHP_STREAM_IS_STDIO) &&
+	    src->writepos == src->readpos &&
+	    php_stream_can_cast(src, PHP_STREAM_AS_FD) == SUCCESS &&
+	    php_stream_can_cast(dest, PHP_STREAM_AS_FD) == SUCCESS) {
+		/* both php_stream instances are backed by a file
+		   descriptor, are not filtered and the read buffer is
+		   empty: we can use copy_file_range() */
+
+		int src_fd, dest_fd;
+
+		php_stream_cast(src, PHP_STREAM_AS_FD, (void*)&src_fd, 0);
+		php_stream_cast(dest, PHP_STREAM_AS_FD, (void*)&dest_fd, 0);
+
+		/* clamp to INT_MAX to avoid EOVERFLOW */
+		const size_t cfr_max = MIN(maxlen, (size_t)SSIZE_MAX);
+
+		/* copy_file_range() is a Linux-specific system call
+		   which allows efficient copying between two file
+		   descriptors, eliminating the need to transfer data
+		   from the kernel to userspace and back.  For
+		   networking file systems like NFS and Ceph, it even
+		   eliminates copying data to the client, and local
+		   filesystems like Btrfs and XFS can create shared
+		   extents. */
+
+		ssize_t result = copy_file_range(src_fd, NULL,
+						 dest_fd, NULL,
+						 cfr_max, 0);
+		if (result > 0) {
+			size_t nbytes = (size_t)result;
+			haveread += nbytes;
+
+			src->position += nbytes;
+			dest->position += nbytes;
+
+			if ((maxlen != PHP_STREAM_COPY_ALL && nbytes == maxlen) ||
+			    php_stream_eof(src)) {
+				/* the whole request was satisfied or
+				   end-of-file reached - done */
+				*len = haveread;
+				return SUCCESS;
+			}
+
+			/* there may be more data; continue copying
+			   using the fallback code below */
+		} else if (result == 0) {
+			/* end of file */
+			*len = haveread;
+			return SUCCESS;
+		} else if (result < 0) {
+			switch (errno) {
+			case EINVAL:
+				/* some formal error, e.g. overlapping
+				   file ranges */
+				break;
+
+			case EXDEV:
+				/* pre Linux 5.3 error */
+				break;
+
+			case ENOSYS:
+				/* not implemented by this Linux kernel */
+				break;
+
+			default:
+				/* unexpected I/O error - give up, no
+				   fallback */
+				*len = haveread;
+				return FAILURE;
+			}
+
+			/* fall back to classic copying */
+		}
+	}
+#endif // __FreeBSD__
+#endif // HAVE_COPY_FILE_RANGE
+
 	if (maxlen == PHP_STREAM_COPY_ALL) {
 		maxlen = 0;
 	}