Fixed bug #47997 (stream_copy_to_stream returns 1 on empty streams)

NEWS

@@ -12,6 +12,7 @@ PHP                                                                        NEWS
   disable this behaviour using "http"=>array("auto_decode"=>0) in stream
   context. (Dmitry)
 
+- Fixed bug #47997 (stream_copy_to_stream returns 1 on empty streams). (Arnaud)
 - Fixed bug #47880 (crashes in call_user_func_array()). (Dmitry)
 - Fixed bug #47856 (stristr() converts needle to lower-case). (Ilia)
 - Fixed bug #47851 (is_callable throws fatal error). (Dmitry)

ext/standard/file.c

@@ -627,7 +627,10 @@ PHP_FUNCTION(file_put_contents)
 
 	switch (Z_TYPE_P(data)) {
 		case IS_RESOURCE:
-			numbytes = php_stream_copy_to_stream(srcstream, stream, PHP_STREAM_COPY_ALL);
+			numbytes = (int) php_stream_copy_to_stream_ex(srcstream, stream, PHP_STREAM_COPY_ALL);
+			if ((size_t)numbytes == PHP_STREAM_FAILURE) {
+				numbytes = -1;
+			}
 			break;
 		case IS_NULL:
 		case IS_LONG:
@@ -1783,7 +1786,7 @@ safe_to_copy:
 	deststream = php_stream_open_wrapper(dest, "wb", ENFORCE_SAFE_MODE | REPORT_ERRORS, NULL);
 
 	if (srcstream && deststream) {
-		ret = php_stream_copy_to_stream(srcstream, deststream, PHP_STREAM_COPY_ALL) == 0 ? FAILURE : SUCCESS;
+		ret = php_stream_copy_to_stream_ex(srcstream, deststream, PHP_STREAM_COPY_ALL) == PHP_STREAM_FAILURE ? FAILURE : SUCCESS;
 	}
 	if (srcstream) {
 		php_stream_close(srcstream);

ext/standard/streamsfuncs.c

@@ -443,6 +443,7 @@ PHP_FUNCTION(stream_copy_to_stream)
 	php_stream *src, *dest;
 	zval *zsrc, *zdest;
 	long maxlen = PHP_STREAM_COPY_ALL, pos = 0;
+	size_t ret;
 
 	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "rr|ll", &zsrc, &zdest, &maxlen, &pos) == FAILURE) {
 		RETURN_FALSE;
@@ -456,7 +457,12 @@ PHP_FUNCTION(stream_copy_to_stream)
 		RETURN_FALSE;
 	}
 
-	RETURN_LONG(php_stream_copy_to_stream(src, dest, maxlen));
+	ret = php_stream_copy_to_stream_ex(src, dest, maxlen);
+
+	if (ret == PHP_STREAM_FAILURE) {
+		RETURN_FALSE;
+	}
+	RETURN_LONG(ret);
 }
 /* }}} */
 

main/php_streams.h

@@ -420,9 +420,14 @@ END_EXTERN_C()
  * Uses mmap if the src is a plain file and at offset 0 */
 #define PHP_STREAM_COPY_ALL		((size_t)-1)
 
+#define PHP_STREAM_FAILURE		((size_t)-1)
+
 BEGIN_EXTERN_C()
+ZEND_ATTRIBUTE_DEPRECATED
 PHPAPI size_t _php_stream_copy_to_stream(php_stream *src, php_stream *dest, size_t maxlen STREAMS_DC TSRMLS_DC);
 #define php_stream_copy_to_stream(src, dest, maxlen)	_php_stream_copy_to_stream((src), (dest), (maxlen) STREAMS_CC TSRMLS_CC)
+PHPAPI size_t _php_stream_copy_to_stream_ex(php_stream *src, php_stream *dest, size_t maxlen STREAMS_DC TSRMLS_DC);
+#define php_stream_copy_to_stream_ex(src, dest, maxlen)	_php_stream_copy_to_stream_ex((src), (dest), (maxlen) STREAMS_CC TSRMLS_CC)
 
 
 /* read all data from stream and put into a buffer. Caller must free buffer when done.

main/streams/cast.c

@@ -214,9 +214,9 @@ PHPAPI int _php_stream_cast(php_stream *stream, int castas, void **ret, int show
 
 			newstream = php_stream_fopen_tmpfile();
 			if (newstream) {
-				size_t copied = php_stream_copy_to_stream(stream, newstream, PHP_STREAM_COPY_ALL);
+				size_t copied = php_stream_copy_to_stream_ex(stream, newstream, PHP_STREAM_COPY_ALL);
 
-				if (copied == 0) {
+				if (copied == PHP_STREAM_FAILURE) {
 					php_stream_close(newstream);
 				} else {
 					int retcode = php_stream_cast(newstream, castas | flags, ret, show_err);
@@ -332,7 +332,7 @@ PHPAPI int _php_stream_make_seekable(php_stream *origstream, php_stream **newstr
 	(*newstream)->open_lineno = origstream->open_lineno;
 #endif
 
-	if (php_stream_copy_to_stream(origstream, *newstream, PHP_STREAM_COPY_ALL) == 0) {
+	if (php_stream_copy_to_stream_ex(origstream, *newstream, PHP_STREAM_COPY_ALL) == PHP_STREAM_FAILURE) {
 		php_stream_close(*newstream);
 		*newstream = NULL;
 		return PHP_STREAM_CRITICAL;

main/streams/streams.c

@@ -1297,7 +1297,8 @@ PHPAPI size_t _php_stream_copy_to_mem(php_stream *src, char **buf, size_t maxlen
 	return len;
 }
 
-PHPAPI size_t _php_stream_copy_to_stream(php_stream *src, php_stream *dest, size_t maxlen STREAMS_DC TSRMLS_DC)
+/* Returns the number of bytes moved, or PHP_STREAM_FAILURE on failure. */
+PHPAPI size_t _php_stream_copy_to_stream_ex(php_stream *src, php_stream *dest, size_t maxlen STREAMS_DC TSRMLS_DC)
 {
 	char buf[CHUNK_SIZE];
 	size_t readchunk;
@@ -1314,8 +1315,6 @@ PHPAPI size_t _php_stream_copy_to_stream(php_stream *src, php_stream *dest, size
 	}
 
 	if (php_stream_stat(src, &ssbuf) == 0) {
-		/* in the event that the source file is 0 bytes, return 1 to indicate success
-		 * because opening the file to write had already created a copy */
 		if (ssbuf.sb.st_size == 0
 #ifdef S_ISFIFO
 		 && !S_ISFIFO(ssbuf.sb.st_mode)
@@ -1324,7 +1323,7 @@ PHPAPI size_t _php_stream_copy_to_stream(php_stream *src, php_stream *dest, size
 		 && !S_ISCHR(ssbuf.sb.st_mode)
 #endif
 		) {
-			return 1;
+			return 0;
 		}
 	}
 
@@ -1339,7 +1338,13 @@ PHPAPI size_t _php_stream_copy_to_stream(php_stream *src, php_stream *dest, size
 
 			php_stream_mmap_unmap(src);
 			
-			return mapped;
+			/* we've got at least 1 byte to read. 
+			 * less than 1 is an error */
+
+			if (mapped > 0) {
+				return mapped;
+			}
+			return PHP_STREAM_FAILURE;
 		}
 	}
 
@@ -1364,14 +1369,14 @@ PHPAPI size_t _php_stream_copy_to_stream(php_stream *src, php_stream *dest, size
 			while(towrite) {
 				didwrite = php_stream_write(dest, writeptr, towrite);
 				if (didwrite == 0) {
-					return 0;	/* error */
+					return PHP_STREAM_FAILURE;
 				}
 
 				towrite -= didwrite;
 				writeptr += didwrite;
 			}
 		} else {
-			return haveread;
+			break;
 		}
 
 		if (maxlen - haveread == 0) {
@@ -1379,7 +1384,26 @@ PHPAPI size_t _php_stream_copy_to_stream(php_stream *src, php_stream *dest, size
 		}
 	}
 
-	return haveread;
+	/* we've got at least 1 byte to read. 
+	 * less than 1 is an error */
+
+	if (haveread > 0) {
+		return haveread;
+	}
+	return PHP_STREAM_FAILURE;
+}
+
+/* Returns the number of bytes moved.
+ * Returns 1 when source len is 0. 
+ * Deprecated in favor of php_stream_copy_to_stream_ex() */
+ZEND_ATTRIBUTE_DEPRECATED
+PHPAPI size_t _php_stream_copy_to_stream(php_stream *src, php_stream *dest, size_t maxlen STREAMS_DC TSRMLS_DC)
+{
+	size_t ret = _php_stream_copy_to_stream_ex(src, dest, maxlen STREAMS_REL_CC TSRMLS_CC);
+	if (ret == 0 && maxlen != 0) {
+		return 1;
+	}
+	return ret;
 }
 /* }}} */