Bug->Doc #71849 [Opn->Nab]: file_get_contents returns undocumented type

Edit report at https://bugs.php.net/bug.php?id=71849&edit=1 ID: 71849 Updated by: cmb@php.net Reported by: hanskrentel at yahoo dot de Summary: file_get_contents returns undocumented type -Status: Open +Status: Not a bug -Type: Bug +Type: Documentation Problem Package: *General Issues Operating System: Linux PHP Version: 7.0.4 -Assigned To: +Assigned To: cmb Block user comment: N Private report: N New Comment: Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php See the note on <http://php.net/manual/en/functions.internal.php>: > Note: If the parameters given to a function are not what it > expects, such as passing an array where a string is expected, > the return value of the function is undefined. In this case it > will likely return NULL but this is just a convention, and > cannot be relied upon. Previous Comments: ------------------------------------------------------------------------ [2016-03-18 11:08:24] yohgaki@php.net File path cannot contain NUL char. /* Parse arguments */ if (zend_parse_parameters(ZEND_NUM_ARGS(), "p|br!ll", &filename, &filename_len, &use_include_path, &zcontext, &offset, &maxlen) == FAILURE) { return; } "p" is used and "\0" results in invalid path and zend_parse_parameters() fails. That's the reason why it returns NULL. All other functions that expects file path returns NULL for "\0" due to zend_parse_parameters() failure. ------------------------------------------------------------------------ [2016-03-18 00:18:05] hanskrentel at yahoo dot de Example is <https://3v4l.org/33O0B>: <?php var_dump(file_get_contents("\0")); ------------------------------------------------------------------------ [2016-03-18 00:13:56] hanskrentel at yahoo dot de Description: ------------ I managed to make file_get_contents() return NULL which is undocumented (string and FALSE is documented). Technically the case ("\0" as filename) triggers a warning so might not construe an error, but actually smells a lot like an error finally and should be FALSE. This would also reduce handling return value logic. So far it's merely unnoticed as undocumented, no idea if it's a technical difficulty to fix or just an oversight. As this is NUL byte related this might make underlying problems visible. As I'm undecided, I filed it as bug. It could be a documentation problem or security issue. Also a change request. As it could be all three, I filed it as bug which is undefined as well. HTH ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=71849&edit=1