From aa0c4b0df7cdc750450906aff4e8c81627d80605 Mon Sep 17 00:00:00 2001 From: Paul Schoenfelder Date: Tue, 31 Jan 2017 17:40:34 -0600 Subject: Update erl_tar to support PAX format, etc. This commit introduces the following key changes: - Support for reading tar archives in formats currently in common use, such as v7, STAR, USTAR, PAX, and GNU tar's extensions to the STAR/USTAR format. - Support for writing PAX archives, only when necessary, using USTAR when possible for greater portability. These changes result in lifting of some prior restrictions: - Support for reading archives produced by modern tar implementations when other restrictions described below are present. - Support for filenames which exceed 100 bytes in length, or paths which exceed 255 bytes (see USTAR format specification for more details on this restriction). - Support for filenames of arbitrary length - Support for unicode metadata (the previous behaviour of erl_tar was actually violating the spec, by writing unicode-encoded data to fields which are defined to be 7-bit ASCII, even though this technically worked when using erl_tar at source and destination, it may not have worked with other tar utilities, and this implementation now conforms to the spec). - Support for uid/gid values which cannot be converted to octal integers. --- lib/stdlib/src/erl_tar.hrl | 394 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 394 insertions(+) create mode 100644 lib/stdlib/src/erl_tar.hrl (limited to 'lib/stdlib/src/erl_tar.hrl') diff --git a/lib/stdlib/src/erl_tar.hrl b/lib/stdlib/src/erl_tar.hrl new file mode 100644 index 0000000000..d646d02989 --- /dev/null +++ b/lib/stdlib/src/erl_tar.hrl @@ -0,0 +1,394 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 2017. 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. +%% You may obtain a copy of the License at +%% +%% http://www.apache.org/licenses/LICENSE-2.0 +%% +%% Unless required by applicable law or agreed to in writing, software +%% distributed under the License is distributed on an "AS IS" BASIS, +%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +%% See the License for the specific language governing permissions and +%% limitations under the License. +%% +%% %CopyrightEnd% + +%% Options used when adding files to a tar archive. +-record(add_opts, { + read_info, %% Fun to use for read file/link info. + chunk_size = 0, %% For file reading when sending to sftp. 0=do not chunk + verbose = false}). %% Verbose on/off. +-type add_opts() :: #add_opts{}. + +%% Options used when reading a tar archive. +-record(read_opts, { + cwd :: string(), %% Current working directory. + keep_old_files = false :: boolean(), %% Owerwrite or not. + files = all, %% Set of files to extract (or all) + output = file :: 'file' | 'memory', + open_mode = [], %% Open mode options. + verbose = false :: boolean()}). %% Verbose on/off. +-type read_opts() :: #read_opts{}. + +-type add_opt() :: dereference | + verbose | + {chunks, pos_integer()}. + +-type extract_opt() :: {cwd, string()} | + {files, [string()]} | + compressed | + cooked | + memory | + keep_old_files | + verbose. + +-type create_opt() :: compressed | + cooked | + dereference | + verbose. + +-type filelist() :: [file:filename() | + {string(), binary()} | + {string(), file:filename()}]. + +%% The tar header, once fully parsed. +-record(tar_header, { + name = "" :: string(), %% name of header file entry + mode = 8#100644 :: non_neg_integer(), %% permission and mode bits + uid = 0 :: non_neg_integer(), %% user id of owner + gid = 0 :: non_neg_integer(), %% group id of owner + size = 0 :: non_neg_integer(), %% length in bytes + mtime :: calendar:datetime(), %% modified time + typeflag :: char(), %% type of header entry + linkname = "" :: string(), %% target name of link + uname = "" :: string(), %% user name of owner + gname = "" :: string(), %% group name of owner + devmajor = 0 :: non_neg_integer(), %% major number of character or block device + devminor = 0 :: non_neg_integer(), %% minor number of character or block device + atime :: calendar:datetime(), %% access time + ctime :: calendar:datetime() %% status change time + }). +-type tar_header() :: #tar_header{}. + +%% Metadata for a sparse file fragment +-record(sparse_entry, { + offset = 0 :: non_neg_integer(), + num_bytes = 0 :: non_neg_integer()}). +-type sparse_entry() :: #sparse_entry{}. +%% Contains metadata about fragments of a sparse file +-record(sparse_array, { + entries = [] :: [sparse_entry()], + is_extended = false :: boolean(), + max_entries = 0 :: non_neg_integer()}). +-type sparse_array() :: #sparse_array{}. +%% A subset of tar header fields common to all tar implementations +-record(header_v7, { + name :: binary(), + mode :: binary(), %% octal + uid :: binary(), %% integer + gid :: binary(), %% integer + size :: binary(), %% integer + mtime :: binary(), %% integer + checksum :: binary(), %% integer + typeflag :: byte(), %% char + linkname :: binary()}). +-type header_v7() :: #header_v7{}. +%% The set of fields specific to GNU tar formatted archives +-record(header_gnu, { + header_v7 :: header_v7(), + magic :: binary(), + version :: binary(), + uname :: binary(), + gname :: binary(), + devmajor :: binary(), %% integer + devminor :: binary(), %% integer + atime :: binary(), %% integer + ctime :: binary(), %% integer + sparse :: sparse_array(), + real_size :: binary()}). %% integer +-type header_gnu() :: #header_gnu{}. +%% The set of fields specific to STAR-formatted archives +-record(header_star, { + header_v7 :: header_v7(), + magic :: binary(), + version :: binary(), + uname :: binary(), + gname :: binary(), + devmajor :: binary(), %% integer + devminor :: binary(), %% integer + prefix :: binary(), + atime :: binary(), %% integer + ctime :: binary(), %% integer + trailer :: binary()}). +-type header_star() :: #header_star{}. +%% The set of fields specific to USTAR-formatted archives +-record(header_ustar, { + header_v7 :: header_v7(), + magic :: binary(), + version :: binary(), + uname :: binary(), + gname :: binary(), + devmajor :: binary(), %% integer + devminor :: binary(), %% integer + prefix :: binary()}). +-type header_ustar() :: #header_ustar{}. + +-type header_fields() :: header_v7() | + header_gnu() | + header_star() | + header_ustar(). + +%% The overall tar reader, it holds the low-level file handle, +%% its access, position, and the I/O primitives wrapper. +-record(reader, { + handle :: file:io_device() | term(), + access :: read | write | ram, + pos = 0 :: non_neg_integer(), + func :: file_op() + }). +-type reader() :: #reader{}. +%% A reader for a regular file within the tar archive, +%% It tracks its current state relative to that file. +-record(reg_file_reader, { + handle :: reader(), + num_bytes = 0, + pos = 0, + size = 0 + }). +-type reg_file_reader() :: #reg_file_reader{}. +%% A reader for a sparse file within the tar archive, +%% It tracks its current state relative to that file. +-record(sparse_file_reader, { + handle :: reader(), + num_bytes = 0, %% bytes remaining + pos = 0, %% pos + size = 0, %% total size of file + sparse_map = #sparse_array{} + }). +-type sparse_file_reader() :: #sparse_file_reader{}. + +%% Types for the readers +-type reader_type() :: reader() | reg_file_reader() | sparse_file_reader(). +-type handle() :: file:io_device() | term(). + +%% Type for the I/O primitive wrapper function +-type file_op() :: fun((write | close | read2 | position, + {handle(), iodata()} | handle() | {handle(), non_neg_integer()} + | {handle(), non_neg_integer()}) -> + ok | eof | {ok, string() | binary()} | {ok, non_neg_integer()} + | {error, term()}). + +%% These constants (except S_IFMT) are +%% used to determine what type of device +%% a file is. Namely, `S_IFMT band file_info.mode` +%% will equal one of these contants, and tells us +%% which type it is. The stdlib file_info record +%% does not differentiate between device types, and +%% will not allow us to differentiate between sockets +%% and named pipes. These constants are pulled from libc. +-define(S_IFMT, 61440). +-define(S_IFSOCK, 49152). %% socket +-define(S_FIFO, 4096). %% fifo/named pipe +-define(S_IFBLK, 24576). %% block device +-define(S_IFCHR, 8192). %% character device + +%% Typeflag constants for the tar header +-define(TYPE_REGULAR, $0). %% regular file +-define(TYPE_REGULAR_A, 0). %% regular file +-define(TYPE_LINK, $1). %% hard link +-define(TYPE_SYMLINK, $2). %% symbolic link +-define(TYPE_CHAR, $3). %% character device node +-define(TYPE_BLOCK, $4). %% block device node +-define(TYPE_DIR, $5). %% directory +-define(TYPE_FIFO, $6). %% fifo node +-define(TYPE_CONT, $7). %% reserved +-define(TYPE_X_HEADER, $x). %% extended header +-define(TYPE_X_GLOBAL_HEADER, $g). %% global extended header +-define(TYPE_GNU_LONGNAME, $L). %% next file has a long name +-define(TYPE_GNU_LONGLINK, $K). %% next file symlinks to a file with a long name +-define(TYPE_GNU_SPARSE, $S). %% sparse file + +%% Mode constants from tar spec +-define(MODE_ISUID, 4000). %% set uid +-define(MODE_ISGID, 2000). %% set gid +-define(MODE_ISVTX, 1000). %% save text (sticky bit) +-define(MODE_ISDIR, 40000). %% directory +-define(MODE_ISFIFO, 10000). %% fifo +-define(MODE_ISREG, 100000). %% regular file +-define(MODE_ISLNK, 120000). %% symbolic link +-define(MODE_ISBLK, 60000). %% block special file +-define(MODE_ISCHR, 20000). %% character special file +-define(MODE_ISSOCK, 140000). %% socket + +%% Keywords for PAX extended header +-define(PAX_ATIME, <<"atime">>). +-define(PAX_CHARSET, <<"charset">>). +-define(PAX_COMMENT, <<"comment">>). +-define(PAX_CTIME, <<"ctime">>). %% ctime is not a valid pax header +-define(PAX_GID, <<"gid">>). +-define(PAX_GNAME, <<"gname">>). +-define(PAX_LINKPATH, <<"linkpath">>). +-define(PAX_MTIME, <<"mtime">>). +-define(PAX_PATH, <<"path">>). +-define(PAX_SIZE, <<"size">>). +-define(PAX_UID, <<"uid">>). +-define(PAX_UNAME, <<"uname">>). +-define(PAX_XATTR, <<"SCHILY.xattr.">>). +-define(PAX_XATTR_STR, "SCHILY.xattr."). +-define(PAX_NONE, <<"">>). + +%% Tar format constants +%% Unknown format +-define(FORMAT_UNKNOWN, 0). +%% The format of the original Unix V7 tar tool prior to standardization +-define(FORMAT_V7, 1). +%% The old and new GNU formats, incompatible with USTAR. +%% This covers the old GNU sparse extension, but it does +%% not cover the GNU sparse extensions using PAX headers, +%% versions 0.0, 0.1, and 1.0; these fall under the PAX format. +-define(FORMAT_GNU, 2). +%% Schily's tar format, which is incompatible with USTAR. +%% This does not cover STAR extensions to the PAX format; these +%% fall under the PAX format. +-define(FORMAT_STAR, 3). +%% USTAR is the former standardization of tar defined in POSIX.1-1988, +%% it is incompatible with the GNU and STAR formats. +-define(FORMAT_USTAR, 4). +%% PAX is the latest standardization of tar defined in POSIX.1-2001. +%% This is an extension of USTAR and is "backwards compatible" with it. +%% +%% Some newer formats add their own extensions to PAX, such as GNU sparse +%% files and SCHILY extended attributes. Since they are backwards compatible +%% with PAX, they will be labelled as "PAX". +-define(FORMAT_PAX, 5). + +%% Magic constants +-define(MAGIC_GNU, <<"ustar ">>). +-define(VERSION_GNU, <<" \x00">>). +-define(MAGIC_USTAR, <<"ustar\x00">>). +-define(VERSION_USTAR, <<"00">>). +-define(TRAILER_STAR, <<"tar\x00">>). + +%% Size constants +-define(BLOCK_SIZE, 512). %% size of each block in a tar stream +-define(NAME_SIZE, 100). %% max length of the name field in USTAR format +-define(PREFIX_SIZE, 155). %% max length of the prefix field in USTAR format + +%% Maximum size of a nanosecond value as an integer +-define(MAX_NANO_INT_SIZE, 9). +%% Maximum size of a 64-bit signed integer +-define(MAX_INT64, (1 bsl 63 - 1)). + +-define(PAX_GNU_SPARSE_NUMBLOCKS, <<"GNU.sparse.numblocks">>). +-define(PAX_GNU_SPARSE_OFFSET, <<"GNU.sparse.offset">>). +-define(PAX_GNU_SPARSE_NUMBYTES, <<"GNU.sparse.numbytes">>). +-define(PAX_GNU_SPARSE_MAP, <<"GNU.sparse.map">>). +-define(PAX_GNU_SPARSE_NAME, <<"GNU.sparse.name">>). +-define(PAX_GNU_SPARSE_MAJOR, <<"GNU.sparse.major">>). +-define(PAX_GNU_SPARSE_MINOR, <<"GNU.sparse.minor">>). +-define(PAX_GNU_SPARSE_SIZE, <<"GNU.sparse.size">>). +-define(PAX_GNU_SPARSE_REALSIZE, <<"GNU.sparse.realsize">>). + +-define(V7_NAME, 0). +-define(V7_NAME_LEN, 100). +-define(V7_MODE, 100). +-define(V7_MODE_LEN, 8). +-define(V7_UID, 108). +-define(V7_UID_LEN, 8). +-define(V7_GID, 116). +-define(V7_GID_LEN, 8). +-define(V7_SIZE, 124). +-define(V7_SIZE_LEN, 12). +-define(V7_MTIME, 136). +-define(V7_MTIME_LEN, 12). +-define(V7_CHKSUM, 148). +-define(V7_CHKSUM_LEN, 8). +-define(V7_TYPE, 156). +-define(V7_TYPE_LEN, 1). +-define(V7_LINKNAME, 157). +-define(V7_LINKNAME_LEN, 100). + +-define(STAR_TRAILER, 508). +-define(STAR_TRAILER_LEN, 4). + +-define(USTAR_MAGIC, 257). +-define(USTAR_MAGIC_LEN, 6). +-define(USTAR_VERSION, 263). +-define(USTAR_VERSION_LEN, 2). +-define(USTAR_UNAME, 265). +-define(USTAR_UNAME_LEN, 32). +-define(USTAR_GNAME, 297). +-define(USTAR_GNAME_LEN, 32). +-define(USTAR_DEVMAJ, 329). +-define(USTAR_DEVMAJ_LEN, 8). +-define(USTAR_DEVMIN, 337). +-define(USTAR_DEVMIN_LEN, 8). +-define(USTAR_PREFIX, 345). +-define(USTAR_PREFIX_LEN, 155). + +-define(GNU_MAGIC, 257). +-define(GNU_MAGIC_LEN, 6). +-define(GNU_VERSION, 263). +-define(GNU_VERSION_LEN, 2). + +%% ?BLOCK_SIZE of zero-bytes. +%% Two of these in a row mark the end of an archive. +-define(ZERO_BLOCK, <<0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0,0,0>>). + +-define(BILLION, 1000000000). + +-define(EPOCH, {{1970,1,1}, {0,0,0}}). -- cgit v1.2.3