Update Encryption.php

Signed-off-by: martink-p <47943787+martink-p@users.noreply.github.com>

1 files changed, 19 insertions, 2 deletions

diff --git a/lib/private/Files/Stream/Encryption.php b/lib/private/Files/Stream/Encryption.php
index 3c884a99ae7..bdbbc8a06ff 100644
--- a/lib/private/Files/Stream/Encryption.php
+++ b/lib/private/Files/Stream/Encryption.php
@@ -315,6 +315,23 @@ class Encryption extends Wrapper {
 		return $result;
 
 	}
+	
+	/**
+	* stream_read wrapper to read complete requested block
+	*/
+	private function stream_read_block($blockSize) {
+		$remaining = $blockSize;
+		$data = "";
+
+		do {
+			$chunk = parent::stream_read($remaining);
+			$chunk_len = strlen($chunk);
+			$data .= $chunk;
+			$remaining -= $chunk_len;
+		} while ( ($remaining > 0) && ($chunk_len > 0) );
+
+		return $data;
+	}
 
 	public function stream_write($data) {
 		$length = 0;
@@ -470,7 +487,7 @@ class Encryption extends Wrapper {
 		// don't try to fill the cache when trying to write at the end of the unencrypted file when it coincides with new block
 		if ($this->cache === '' && !($this->position === $this->unencryptedSize && ($this->position % $this->unencryptedBlockSize) === 0)) {
 			// Get the data from the file handle
-			$data = parent::stream_read($this->util->getBlockSize());
+			$data = $this->stream_read_block($this->util->getBlockSize());
 			$position = (int)floor($this->position/$this->unencryptedBlockSize);
 			$numberOfChunks = (int)($this->unencryptedSize / $this->unencryptedBlockSize);
 			if($numberOfChunks === $position) {
@@ -495,7 +512,7 @@ class Encryption extends Wrapper {
 	 * read first block to skip the header
 	 */
 	protected function skipHeader() {
-		parent::stream_read($this->headerSize);
+		$this->stream_read_block($this->headerSize);
 	}
 
 	/**