diff options
Diffstat (limited to 'lib/stdlib/src/filename.erl')
| -rw-r--r-- | lib/stdlib/src/filename.erl | 137 |
1 files changed, 124 insertions, 13 deletions
diff --git a/lib/stdlib/src/filename.erl b/lib/stdlib/src/filename.erl index ee807dfd09..b7b7b562ab 100644 --- a/lib/stdlib/src/filename.erl +++ b/lib/stdlib/src/filename.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1997-2017. All Rights Reserved. +%% Copyright Ericsson AB 1997-2018. All Rights Reserved. %% %% Licensed under the Apache License, Version 2.0 (the "License"); %% you may not use this file except in compliance with the License. @@ -34,6 +34,38 @@ %% we flatten the arguments immediately on function entry as that makes %% it easier to ensure that the code works. +%% +%% *** Requirements on Raw Filename Format *** +%% +%% These requirements are due to the 'filename' module +%% in stdlib. This since it is documented that it +%% should be able to operate on raw filenames as well +%% as ordinary filenames. +%% +%% A raw filename *must* be a byte sequence where: +%% 1. Codepoints 0-127 (7-bit ascii) *must* be encoded +%% as a byte with the corresponding value. That is, +%% the most significant bit in the byte encoding the +%% codepoint is never set. +%% 2. Codepoints greater than 127 *must* be encoded +%% with the most significant bit set in *every* byte +%% encoding it. +%% +%% Latin1 and UTF-8 meet these requirements while +%% UTF-16 and UTF-32 don't. +%% +%% On Windows filenames are natively stored as malformed +%% UTF-16LE (lonely surrogates may appear). A more correct +%% description than UTF-16 would be an array of 16-bit +%% words... In order to meet the requirements of the +%% raw file format we convert the malformed UTF-16LE to +%% malformed UTF-8 which meet the requirements. +%% +%% Note that these requirements are today only OTP +%% internal (erts-stdlib internal) requirements that +%% could be changed. +%% + -export([absname/1, absname/2, absname_join/2, basename/1, basename/2, dirname/1, extension/1, join/1, join/2, pathtype/1, @@ -41,6 +73,7 @@ safe_relative_path/1]). -export([find_src/1, find_src/2]). % deprecated -export([basedir/2, basedir/3]). +-export([validate/1]). %% Undocumented and unsupported exports. -export([append/2]). @@ -979,24 +1012,33 @@ filename_string_to_binary(List) -> %% basedir %% http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html --type basedir_type() :: 'user_cache' | 'user_config' | 'user_data' - | 'user_log' - | 'site_config' | 'site_data'. +-type basedir_path_type() :: 'user_cache' | 'user_config' | 'user_data' + | 'user_log'. +-type basedir_paths_type() :: 'site_config' | 'site_data'. + +-type basedir_opts() :: #{author => string() | binary(), + os => 'windows' | 'darwin' | 'linux', + version => string() | binary()}. --spec basedir(Type,Application) -> file:filename_all() when - Type :: basedir_type(), +-spec basedir(PathType,Application) -> file:filename_all() when + PathType :: basedir_path_type(), + Application :: string() | binary(); + (PathsType,Application) -> [file:filename_all()] when + PathsType :: basedir_paths_type(), Application :: string() | binary(). basedir(Type,Application) when is_atom(Type), is_list(Application) orelse is_binary(Application) -> basedir(Type, Application, #{}). --spec basedir(Type,Application,Opts) -> file:filename_all() when - Type :: basedir_type(), +-spec basedir(PathType,Application,Opts) -> file:filename_all() when + PathType :: basedir_path_type(), Application :: string() | binary(), - Opts :: #{author => string() | binary(), - os => 'windows' | 'darwin' | 'linux', - version => string() | binary()}. + Opts :: basedir_opts(); + (PathsType,Application,Opts) -> [file:filename_all()] when + PathsType :: basedir_paths_type(), + Application :: string() | binary(), + Opts :: basedir_opts(). basedir(Type,Application,Opts) when is_atom(Type), is_map(Opts), is_list(Application) orelse @@ -1053,10 +1095,10 @@ basedir_linux(Type) -> user_log -> getenv("XDG_CACHE_HOME", ?basedir_linux_user_log, true); site_data -> Base = getenv("XDG_DATA_DIRS",?basedir_linux_site_data,false), - string:tokens(Base,":"); + string:lexemes(Base, ":"); site_config -> Base = getenv("XDG_CONFIG_DIRS",?basedir_linux_site_config,false), - string:tokens(Base,":") + string:lexemes(Base, ":") end. -define(basedir_darwin_user_data, "Library/Application Support"). @@ -1152,3 +1194,72 @@ basedir_os_type() -> {win32,_} -> windows; _ -> linux end. + +%% +%% validate/1 +%% + +-spec validate(FileName) -> boolean() when + FileName :: file:name_all(). + +validate(FileName) when is_binary(FileName) -> + %% Raw filename... + validate_bin(FileName); +validate(FileName) when is_list(FileName); + is_atom(FileName) -> + validate_list(FileName, + file:native_name_encoding(), + os:type()). + +validate_list(FileName, Enc, Os) -> + try + true = validate_list(FileName, Enc, Os, 0) > 0 + catch + _ : _ -> false + end. + +validate_list([], _Enc, _Os, Chars) -> + Chars; +validate_list(C, Enc, Os, Chars) when is_integer(C) -> + validate_char(C, Enc, Os), + Chars+1; +validate_list(A, Enc, Os, Chars) when is_atom(A) -> + validate_list(atom_to_list(A), Enc, Os, Chars); +validate_list([H|T], Enc, Os, Chars) -> + NewChars = validate_list(H, Enc, Os, Chars), + validate_list(T, Enc, Os, NewChars). + +%% C is always an integer... +% validate_char(C, _, _) when not is_integer(C) -> +% throw(invalid); +validate_char(C, _, _) when C < 1 -> + throw(invalid); %% No negative or null characters... +validate_char(C, latin1, _) when C > 255 -> + throw(invalid); +validate_char(C, utf8, _) when C >= 16#110000 -> + throw(invalid); +validate_char(C, utf8, {win32, _}) when C > 16#ffff -> + throw(invalid); %% invalid win wchar... +validate_char(_C, utf8, {win32, _}) -> + ok; %% Range below is accepted on windows... +validate_char(C, utf8, _) when 16#D800 =< C, C =< 16#DFFF -> + throw(invalid); %% invalid unicode range... +validate_char(_, _, _) -> + ok. + +validate_bin(Bin) -> + %% Raw filename. That is, we do not interpret + %% the encoding, but we still do not accept + %% null characters... + try + true = validate_bin(Bin, 0) > 0 + catch + _ : _ -> false + end. + +validate_bin(<<>>, Bs) -> + Bs; +validate_bin(<<0, _Rest/binary>>, _Bs) -> + throw(invalid); %% No null characters allowed... +validate_bin(<<_B, Rest/binary>>, Bs) -> + validate_bin(Rest, Bs+1). |