Fix assertion failure when failing to detect encoding

Looks like prior to 7.3 this just passed the original string
through. Since 7.3 it returns false. Let's stick with that
behavior.

diff --git a/ext/mbstring/mbstring.c b/ext/mbstring/mbstring.c
index f636d51b025353808a1c3993b99d925ccc90b5fb..a529f848091186c0271e88c036cea4aa44f70a3b 100644 (file)
--- a/ext/mbstring/mbstring.c
+++ b/ext/mbstring/mbstring.c
@@ -2489,9 +2489,6 @@ MBSTRING_API char *php_mb_convert_encoding(const char *input, size_t length, con
        if (output_len) {
                *output_len = 0;
        }
-       if (!input) {
-               return NULL;
-       }
 
        /* pre-conversion encoding */
        ZEND_ASSERT(num_from_encodings >= 1);
@@ -2507,7 +2504,7 @@ MBSTRING_API char *php_mb_convert_encoding(const char *input, size_t length, con
                        &string, from_encodings, num_from_encodings, MBSTRG(strict_detection));
                if (!from_encoding) {
                        php_error_docref(NULL, E_WARNING, "Unable to detect character encoding");
-                       from_encoding = &mbfl_encoding_pass;
+                       return NULL;
                }
        }
 

diff --git a/ext/mbstring/tests/mb_convert_encoding_failed_detection.phpt b/ext/mbstring/tests/mb_convert_encoding_failed_detection.phpt
new file mode 100644 (file)
index 0000000..961af50
--- /dev/null
+++ b/ext/mbstring/tests/mb_convert_encoding_failed_detection.phpt
@@ -0,0 +1,11 @@
+--TEST--
+mb_convert_encoding() when encoding detection fails
+--FILE--
+<?php
+
+var_dump(mb_convert_encoding("\xff", "ASCII", ["UTF-8", "UTF-16"]));
+
+?>
+--EXPECTF--
+Warning: mb_convert_encoding(): Unable to detect character encoding in %s on line %d
+bool(false)