From eae496a72e270fd7af411714738e99a7fadfd19b Mon Sep 17 00:00:00 2001 From: Rickard Green Date: Wed, 6 Sep 2017 17:00:14 +0200 Subject: Don't allow null in filenames --- lib/stdlib/doc/src/filelib.xml | 24 +++++++++++ lib/stdlib/doc/src/filename.xml | 78 +++++++++++++++++++++++++++++++++++- lib/stdlib/doc/src/unicode_usage.xml | 4 +- 3 files changed, 103 insertions(+), 3 deletions(-) (limited to 'lib/stdlib/doc/src') diff --git a/lib/stdlib/doc/src/filelib.xml b/lib/stdlib/doc/src/filelib.xml index 80c4acffdb..57c4348745 100644 --- a/lib/stdlib/doc/src/filelib.xml +++ b/lib/stdlib/doc/src/filelib.xml @@ -45,6 +45,30 @@

For more information about raw filenames, see the file module.

+ + +

+ Functionality in this module generally assumes valid input and + does not necessarily fail on input that does not use a valid + encoding. You can validate the encoding of a filename using + filename:validate/1. +

+

+ File operations used to accept filenames containing + null characters (integer value zero). This caused + the name to be truncated at the first null character. + Filenames containing null characters inside the filename + are now rejected and will cause primitive + file operations fail. +

+ +

+ Currently null characters at the end of the filename + will be accepted by primitive file operations. Such + filenames are however still documented as invalid. The + implementation will also change in the future and + reject such filenames. +

diff --git a/lib/stdlib/doc/src/filename.xml b/lib/stdlib/doc/src/filename.xml index 14fd5ef787..b6028fc066 100644 --- a/lib/stdlib/doc/src/filename.xml +++ b/lib/stdlib/doc/src/filename.xml @@ -46,7 +46,10 @@ filename by removing redundant directory separators, use join/1.

-

The module supports raw filenames in the way that if a binary is +

+ The module supports + raw + filenames in the way that if a binary is present, or the filename cannot be interpreted according to the return value of file:native_name_encoding/0, a raw filename is also @@ -56,6 +59,30 @@ (the join operation is performed of course). For more information about raw filenames, see the file module.

+ + +

+ Functionality in this module generally assumes valid input and + does not necessarily fail on input that does not use a valid + encoding. You can validate the encoding of a filename using + filename:validate/1. +

+

+ File operations used to accept filenames containing + null characters (integer value zero). This caused + the name to be truncated at the first null character. + Filenames containing null characters inside the filename + are now rejected and will cause primitive + file operations fail. +

+ +

+ Currently null characters at the end of the filename + will be accepted by primitive file operations. Such + filenames are however still documented as invalid. The + implementation will also change in the future and + reject such filenames. +

@@ -555,6 +582,55 @@ unsafe ["a:/","msdev","include"] + + + + Validate encoding of filename + +

+ Validates filename encoding. Returns true if + FileName has a valid encoding; + otherwise, returns false. +

+ + Ordinary Filename + +

+ Type: FileName = file:name() +

+

+ Validates encoding against the + native file + name encoding, and the + capabilities of the operating system used. + Regardless of configuration and OS, null + characters (integer value zero) will be + rejected by the validation (even when only + present at the end of the filename). +

+ + Raw + Filename + +

+ Type: FileName = binary() +

+

+ The encoding will not be interpreted, but + null bytes (integer value zero) will be + rejected by the validation (even when only + present at the end of the filename). +

+ + +

+ For information on filename encoding see the documentation + of unicode filenames in + STDLIB + Users Guide ➜ Using Unicode in Erlang ➜ Unicode Filenames. +

+ + diff --git a/lib/stdlib/doc/src/unicode_usage.xml b/lib/stdlib/doc/src/unicode_usage.xml index 26dc46719e..ff1f864e22 100644 --- a/lib/stdlib/doc/src/unicode_usage.xml +++ b/lib/stdlib/doc/src/unicode_usage.xml @@ -719,8 +719,8 @@ Eshell V5.10.1 (abort with ^G)
- Unicode Filenames + Unicode Filenames

Most modern operating systems support Unicode filenames in some way. There are many different ways to do this and Erlang by default treats the different approaches differently:

@@ -855,8 +855,8 @@ Eshell V5.10.1 (abort with ^G)
- Notes About Raw Filenames + Notes About Raw Filenames

Raw filenames were introduced together with Unicode filename support in ERTS 5.8.2 (Erlang/OTP R14B01). The reason "raw filenames" were introduced in the system was -- cgit v1.2.3