1 files changed, 86 insertions, 0 deletions
diff --git a/vendor/setasign/fpdi/src/PdfParser/Filter/Flate.php b/vendor/setasign/fpdi/src/PdfParser/Filter/Flate.php
new file mode 100644
index 0000000..b8f79d1
--- /dev/null
+++ b/vendor/setasign/fpdi/src/PdfParser/Filter/Flate.php
@@ -0,0 +1,86 @@
+<?php
+
+/**
+ * This file is part of FPDI
+ *
+ * @package   setasign\Fpdi
+ * @copyright Copyright (c) 2020 Setasign GmbH & Co. KG (https://www.setasign.com)
+ * @license   http://opensource.org/licenses/mit-license The MIT License
+ */
+
+namespace setasign\Fpdi\PdfParser\Filter;
+
+/**
+ * Class for handling zlib/deflate encoded data
+ */
+class Flate implements FilterInterface
+{
+    /**
+     * Checks whether the zlib extension is loaded.
+     *
+     * Used for testing purpose.
+     *
+     * @return boolean
+     * @internal
+     */
+    protected function extensionLoaded()
+    {
+        return \extension_loaded('zlib');
+    }
+
+    /**
+     * Decodes a flate compressed string.
+     *
+     * @param string|false $data The input string
+     * @return string
+     * @throws FlateException
+     */
+    public function decode($data)
+    {
+        if ($this->extensionLoaded()) {
+            $oData = $data;
+            $data = (($data !== '') ? @\gzuncompress($data) : '');
+            if ($data === false) {
+                // let's try if the checksum is CRC32
+                $fh = fopen('php://temp', 'w+b');
+                fwrite($fh, "\x1f\x8b\x08\x00\x00\x00\x00\x00" . $oData);
+                stream_filter_append($fh, 'zlib.inflate', STREAM_FILTER_READ, ['window' => 30]);
+                fseek($fh, 0);
+                $data = @stream_get_contents($fh);
+                fclose($fh);
+
+                if ($data) {
+                    return $data;
+                }
+
+                // Try this fallback
+                $tries = 0;
+
+                $oDataLen = strlen($oData);
+                while ($tries < 6 && ($data === false || (strlen($data) < ($oDataLen - $tries - 1)))) {
+                    $data = @(gzinflate(substr($oData, $tries)));
+                    $tries++;
+                }
+
+                // let's use this fallback only if the $data is longer than the original data
+                if (strlen($data) > ($oDataLen - $tries - 1)) {
+                    return $data;
+                }
+
+                if (!$data) {
+                    throw new FlateException(
+                        'Error while decompressing stream.',
+                        FlateException::DECOMPRESS_ERROR
+                    );
+                }
+            }
+        } else {
+            throw new FlateException(
+                'To handle FlateDecode filter, enable zlib support in PHP.',
+                FlateException::NO_ZLIB
+            );
+        }
+
+        return $data;
+    }
+}