%% %% %CopyrightBegin% %% %% Copyright Ericsson AB 2000-2010. All Rights Reserved. %% %% The contents of this file are subject to the Erlang Public License, %% Version 1.1, (the "License"); you may not use this file except in %% compliance with the License. You should have received a copy of the %% Erlang Public License along with this software. If not, it can be %% retrieved online at http://www.erlang.org/. %% %% Software distributed under the License is distributed on an "AS IS" %% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See %% the License for the specific language governing rights and limitations %% under the License. %% %% %CopyrightEnd% %% -module(prim_file). %% Interface module to the file driver. %%% Interface towards a single file's contents. Uses ?FD_DRV. %% Generic file contents operations -export([open/2, close/1, datasync/1, sync/1, advise/4, position/2, truncate/1, write/2, pwrite/2, pwrite/3, read/2, read_line/1, pread/2, pread/3, copy/3]). %% Specialized file operations -export([open/1, open/3]). -export([read_file/1, read_file/2, write_file/2]). -export([ipread_s32bu_p32bu/3]). %%% Interface towards file system and metadata. Uses ?DRV. %% Takes an optional port (opens a ?DRV port per default) as first argument. -export([get_cwd/0, get_cwd/1, get_cwd/2, set_cwd/1, set_cwd/2, delete/1, delete/2, rename/2, rename/3, make_dir/1, make_dir/2, del_dir/1, del_dir/2, read_file_info/1, read_file_info/2, altname/1, altname/2, write_file_info/2, write_file_info/3, make_link/2, make_link/3, make_symlink/2, make_symlink/3, read_link/1, read_link/2, read_link_info/1, read_link_info/2, list_dir/1, list_dir/2]). %% How to start and stop the ?DRV port. -export([start/0, stop/1]). %% Debug exports -export([open_int/4, open_mode/1, open_mode/4]). %%%----------------------------------------------------------------- %%% Includes and defines -include("file.hrl"). -define(DRV, efile). -define(FD_DRV, efile). -define(LARGEFILESIZE, (1 bsl 63)). %% Driver commands -define(FILE_OPEN, 1). -define(FILE_READ, 2). -define(FILE_LSEEK, 3). -define(FILE_WRITE, 4). -define(FILE_FSTAT, 5). -define(FILE_PWD, 6). -define(FILE_READDIR, 7). -define(FILE_CHDIR, 8). -define(FILE_FSYNC, 9). -define(FILE_MKDIR, 10). -define(FILE_DELETE, 11). -define(FILE_RENAME, 12). -define(FILE_RMDIR, 13). -define(FILE_TRUNCATE, 14). -define(FILE_READ_FILE, 15). -define(FILE_WRITE_INFO, 16). -define(FILE_LSTAT, 19). -define(FILE_READLINK, 20). -define(FILE_LINK, 21). -define(FILE_SYMLINK, 22). -define(FILE_CLOSE, 23). -define(FILE_PWRITEV, 24). -define(FILE_PREADV, 25). -define(FILE_SETOPT, 26). -define(FILE_IPREAD, 27). -define(FILE_ALTNAME, 28). -define(FILE_READ_LINE, 29). -define(FILE_FDATASYNC, 30). -define(FILE_ADVISE, 31). %% Driver responses -define(FILE_RESP_OK, 0). -define(FILE_RESP_ERROR, 1). -define(FILE_RESP_DATA, 2). -define(FILE_RESP_NUMBER, 3). -define(FILE_RESP_INFO, 4). -define(FILE_RESP_NUMERR, 5). -define(FILE_RESP_LDATA, 6). -define(FILE_RESP_N2DATA, 7). -define(FILE_RESP_EOF, 8). %% Open modes for the driver's open function. -define(EFILE_MODE_READ, 1). -define(EFILE_MODE_WRITE, 2). -define(EFILE_MODE_READ_WRITE, 3). -define(EFILE_MODE_APPEND, 4). -define(EFILE_COMPRESSED, 8). %% Use this mask to get just the mode bits to be passed to the driver. -define(EFILE_MODE_MASK, 15). %% Seek modes for the driver's seek function. -define(EFILE_SEEK_SET, 0). -define(EFILE_SEEK_CUR, 1). -define(EFILE_SEEK_END, 2). %% Options -define(FILE_OPT_DELAYED_WRITE, 0). -define(FILE_OPT_READ_AHEAD, 1). %% IPREAD variants -define(IPREAD_S32BU_P32BU, 0). %% POSIX file advises -define(POSIX_FADV_NORMAL, 0). -define(POSIX_FADV_RANDOM, 1). -define(POSIX_FADV_SEQUENTIAL, 2). -define(POSIX_FADV_WILLNEED, 3). -define(POSIX_FADV_DONTNEED, 4). -define(POSIX_FADV_NOREUSE, 5). %%%----------------------------------------------------------------- %%% Functions operating on a file through a handle. ?FD_DRV. %%% %%% Generic file contents operations. %%% %%% Supposed to be called by applications through module file. %% Opens a file using the driver port Port. Returns {error, Reason} %% | {ok, FileDescriptor} open(Port, File, ModeList) when is_port(Port), is_list(File), is_list(ModeList) -> case open_mode(ModeList) of {Mode, _Portopts, _Setopts} -> open_int(Port, File, Mode, []); Reason -> {error, Reason} end; open(_,_,_) -> {error, badarg}. %% Opens a file. Returns {error, Reason} | {ok, FileDescriptor}. open(File, ModeList) when is_list(File), is_list(ModeList) -> case open_mode(ModeList) of {Mode, Portopts, Setopts} -> open_int({?FD_DRV, Portopts}, File, Mode, Setopts); Reason -> {error, Reason} end; open(_, _) -> {error, badarg}. %% Opens a port that can be used for open/3 or read_file/2. %% Returns {ok, Port} | {error, Reason}. open(Portopts) when is_list(Portopts) -> case drv_open(?FD_DRV, Portopts) of {error, _} = Error -> Error; Other -> Other end; open(_) -> {error, badarg}. open_int({Driver, Portopts}, File, Mode, Setopts) -> case drv_open(Driver, Portopts) of {ok, Port} -> open_int(Port, File, Mode, Setopts); {error, _} = Error -> Error end; open_int(Port, File, Mode, Setopts) -> M = Mode band ?EFILE_MODE_MASK, case drv_command(Port, [<<?FILE_OPEN, M:32>>, File, 0]) of {ok, Number} -> open_int_setopts(Port, Number, Setopts); Error -> drv_close(Port), Error end. open_int_setopts(Port, Number, []) -> {ok, #file_descriptor{module = ?MODULE, data = {Port, Number}}}; open_int_setopts(Port, Number, [Cmd | Tail]) -> case drv_command(Port, Cmd) of ok -> open_int_setopts(Port, Number, Tail); Error -> drv_close(Port), Error end. %% Returns ok. close(#file_descriptor{module = ?MODULE, data = {Port, _}}) -> case drv_command(Port, <<?FILE_CLOSE>>) of ok -> drv_close(Port); Error -> Error end; %% Closes a port opened with open/1. close(Port) when is_port(Port) -> drv_close(Port). -define(ADVISE(Offs, Len, Adv), <<?FILE_ADVISE, Offs:64/signed, Len:64/signed, Adv:32/signed>>). %% Returns {error, Reason} | ok. advise(#file_descriptor{module = ?MODULE, data = {Port, _}}, Offset, Length, Advise) -> case Advise of normal -> Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_NORMAL), drv_command(Port, Cmd); random -> Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_RANDOM), drv_command(Port, Cmd); sequential -> Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_SEQUENTIAL), drv_command(Port, Cmd); will_need -> Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_WILLNEED), drv_command(Port, Cmd); dont_need -> Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_DONTNEED), drv_command(Port, Cmd); no_reuse -> Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_NOREUSE), drv_command(Port, Cmd); _ -> {error, einval} end. %% Returns {error, Reason} | ok. write(#file_descriptor{module = ?MODULE, data = {Port, _}}, Bytes) -> case drv_command(Port, [?FILE_WRITE,Bytes]) of {ok, _Size} -> ok; Error -> Error end. %% Returns ok | {error, {WrittenCount, Reason}} pwrite(#file_descriptor{module = ?MODULE, data = {Port, _}}, L) when is_list(L) -> pwrite_int(Port, L, 0, [], []). pwrite_int(_, [], 0, [], []) -> ok; pwrite_int(Port, [], N, Spec, Data) -> Header = list_to_binary([<<?FILE_PWRITEV, N:32>> | reverse(Spec)]), case drv_command_raw(Port, [Header | reverse(Data)]) of {ok, _Size} -> ok; Error -> Error end; pwrite_int(Port, [{Offs, Bytes} | T], N, Spec, Data) when is_integer(Offs) -> if -(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE -> pwrite_int(Port, T, N, Spec, Data, Offs, Bytes); true -> {error, einval} end; pwrite_int(_, [_|_], _N, _Spec, _Data) -> {error, badarg}. pwrite_int(Port, T, N, Spec, Data, Offs, Bin) when is_binary(Bin) -> Size = byte_size(Bin), pwrite_int(Port, T, N+1, [<<Offs:64/signed, Size:64>> | Spec], [Bin | Data]); pwrite_int(Port, T, N, Spec, Data, Offs, Bytes) -> try list_to_binary(Bytes) of Bin -> pwrite_int(Port, T, N, Spec, Data, Offs, Bin) catch error:Reason -> {error, Reason} end. %% Returns {error, Reason} | ok. pwrite(#file_descriptor{module = ?MODULE, data = {Port, _}}, Offs, Bytes) when is_integer(Offs) -> if -(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE -> case pwrite_int(Port, [], 0, [], [], Offs, Bytes) of {error, {_, Reason}} -> {error, Reason}; Result -> Result end; true -> {error, einval} end; pwrite(#file_descriptor{module = ?MODULE}, _, _) -> {error, badarg}. %% Returns {error, Reason} | ok. datasync(#file_descriptor{module = ?MODULE, data = {Port, _}}) -> drv_command(Port, [?FILE_FDATASYNC]). %% Returns {error, Reason} | ok. sync(#file_descriptor{module = ?MODULE, data = {Port, _}}) -> drv_command(Port, [?FILE_FSYNC]). %% Returns {ok, Data} | eof | {error, Reason}. read_line(#file_descriptor{module = ?MODULE, data = {Port, _}}) -> case drv_command(Port, <<?FILE_READ_LINE>>) of {ok, {0, _Data}} -> eof; {ok, {_Size, Data}} -> {ok, Data}; {error, enomem} -> erlang:garbage_collect(), case drv_command(Port, <<?FILE_READ_LINE>>) of {ok, {0, _Data}} -> eof; {ok, {_Size, Data}} -> {ok, Data}; Other -> Other end; Error -> Error end. %% Returns {ok, Data} | eof | {error, Reason}. read(#file_descriptor{module = ?MODULE, data = {Port, _}}, Size) when is_integer(Size), 0 =< Size -> if Size < ?LARGEFILESIZE -> case drv_command(Port, <<?FILE_READ, Size:64>>) of {ok, {0, _Data}} when Size =/= 0 -> eof; {ok, {_Size, Data}} -> {ok, Data}; {error, enomem} -> %% Garbage collecting here might help if %% the current processes has some old binaries left. erlang:garbage_collect(), case drv_command(Port, <<?FILE_READ, Size:64>>) of {ok, {0, _Data}} when Size =/= 0 -> eof; {ok, {_Size, Data}} -> {ok, Data}; Other -> Other end; Error -> Error end; true -> {error, einval} end. %% Returns {ok, [Data|eof, ...]} | {error, Reason} pread(#file_descriptor{module = ?MODULE, data = {Port, _}}, L) when is_list(L) -> pread_int(Port, L, 0, []). pread_int(_, [], 0, []) -> {ok, []}; pread_int(Port, [], N, Spec) -> drv_command(Port, [<<?FILE_PREADV, 0:32, N:32>> | reverse(Spec)]); pread_int(Port, [{Offs, Size} | T], N, Spec) when is_integer(Offs), is_integer(Size), 0 =< Size -> if -(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE, Size < ?LARGEFILESIZE -> pread_int(Port, T, N+1, [<<Offs:64/signed, Size:64>> | Spec]); true -> {error, einval} end; pread_int(_, [_|_], _N, _Spec) -> {error, badarg}. %% Returns {ok, Data} | eof | {error, Reason}. pread(#file_descriptor{module = ?MODULE, data = {Port, _}}, Offs, Size) when is_integer(Offs), is_integer(Size), 0 =< Size -> if -(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE, Size < ?LARGEFILESIZE -> case drv_command(Port, <<?FILE_PREADV, 0:32, 1:32, Offs:64/signed, Size:64>>) of {ok, [eof]} -> eof; {ok, [Data]} -> {ok, Data}; Error -> Error end; true -> {error, einval} end; pread(#file_descriptor{module = ?MODULE, data = {_, _}}, _, _) -> {error, badarg}. %% Returns {ok, Position} | {error, Reason}. position(#file_descriptor{module = ?MODULE, data = {Port, _}}, At) -> case lseek_position(At) of {Offs, Whence} when -(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE -> drv_command(Port, <<?FILE_LSEEK, Offs:64/signed, Whence:32>>); {_, _} -> {error, einval}; Reason -> {error, Reason} end. %% Returns {error, Reaseon} | ok. truncate(#file_descriptor{module = ?MODULE, data = {Port, _}}) -> drv_command(Port, <<?FILE_TRUNCATE>>). %% Returns {error, Reason} | {ok, BytesCopied} copy(#file_descriptor{module = ?MODULE} = Source, #file_descriptor{module = ?MODULE} = Dest, Length) when is_integer(Length), Length >= 0; is_atom(Length) -> %% XXX Should be moved down to the driver for optimization. file:copy_opened(Source, Dest, Length). ipread_s32bu_p32bu(#file_descriptor{module = ?MODULE, data = {_, _}} = Handle, Offs, Infinity) when is_atom(Infinity) -> ipread_s32bu_p32bu(Handle, Offs, (1 bsl 31)-1); ipread_s32bu_p32bu(#file_descriptor{module = ?MODULE, data = {Port, _}}, Offs, MaxSize) when is_integer(Offs), is_integer(MaxSize) -> if -(?LARGEFILESIZE) =< Offs, Offs < ?LARGEFILESIZE, 0 =< MaxSize, MaxSize < (1 bsl 31) -> drv_command(Port, <<?FILE_IPREAD, ?IPREAD_S32BU_P32BU, Offs:64, MaxSize:32>>); true -> {error, einval} end; ipread_s32bu_p32bu(#file_descriptor{module = ?MODULE, data = {_, _}}, _Offs, _MaxSize) -> {error, badarg}. %% Returns {ok, Contents} | {error, Reason} read_file(File) -> case drv_open(?FD_DRV, [binary]) of {ok, Port} -> Result = read_file(Port, File), close(Port), Result; {error, _} = Error -> Error end. %% Takes a Port opened with open/1. read_file(Port, File) when is_port(Port) -> Cmd = [?FILE_READ_FILE | File], case drv_command(Port, Cmd) of {error, enomem} -> %% It could possibly help to do a %% garbage collection here, %% if the file server has some references %% to binaries read earlier. erlang:garbage_collect(), drv_command(Port, Cmd); Result -> Result end. %% Returns {error, Reason} | ok. write_file(File, Bin) -> case open(File, [binary, write]) of {ok, Handle} -> Result = write(Handle, Bin), close(Handle), Result; Error -> Error end. %%%----------------------------------------------------------------- %%% Functions operating on files without handle to the file. ?DRV. %%% %%% Supposed to be called by applications through module file. %% Returns {ok, Port}, the Port should be used as first argument in all %% the following functions. Returns {error, Reason} upon failure. start() -> try erlang:open_port({spawn, atom_to_list(?DRV)}, []) of Port -> {ok, Port} catch error:Reason -> {error, Reason} end. stop(Port) when is_port(Port) -> try erlang:port_close(Port) of _ -> ok catch _:_ -> ok end. %%% The following functions take an optional Port as first argument. %%% If the port is not supplied, a temporary one is opened and then %%% closed after the request has been performed. %% get_cwd/{0,1,2} get_cwd() -> get_cwd_int(0). get_cwd(Port) when is_port(Port) -> get_cwd_int(Port, 0); get_cwd([]) -> get_cwd_int(0); get_cwd([Letter, $: | _]) when $a =< Letter, Letter =< $z -> get_cwd_int(Letter - $a + 1); get_cwd([Letter, $: | _]) when $A =< Letter, Letter =< $Z -> get_cwd_int(Letter - $A + 1); get_cwd([_|_]) -> {error, einval}; get_cwd(_) -> {error, badarg}. get_cwd(Port, []) when is_port(Port) -> get_cwd_int(Port, 0); get_cwd(Port, [Letter, $: | _]) when is_port(Port), $a =< Letter, Letter =< $z -> get_cwd_int(Port, Letter - $a + 1); get_cwd(Port, [Letter, $: | _]) when is_port(Port), $A =< Letter, Letter =< $Z -> get_cwd_int(Port, Letter - $A + 1); get_cwd(Port, [_|_]) when is_port(Port) -> {error, einval}; get_cwd(_, _) -> {error, badarg}. get_cwd_int(Drive) -> get_cwd_int({?DRV, []}, Drive). get_cwd_int(Port, Drive) -> drv_command(Port, <<?FILE_PWD, Drive>>). %% set_cwd/{1,2} set_cwd(Dir) -> set_cwd_int({?DRV, []}, Dir). set_cwd(Port, Dir) when is_port(Port) -> set_cwd_int(Port, Dir). set_cwd_int(Port, Dir0) -> Dir = (catch case os:type() of vxworks -> %% chdir on vxworks doesn't support %% relative paths %% must call get_cwd from here and use %% absname/2, since %% absname/1 uses file:get_cwd ... case get_cwd_int(Port, 0) of {ok, AbsPath} -> filename:absname(Dir0, AbsPath); _Badcwd -> Dir0 end; _Else -> Dir0 end), %% Dir is now either a string or an EXIT tuple. %% An EXIT tuple will fail in the following catch. drv_command(Port, [?FILE_CHDIR, Dir, 0]). %% delete/{1,2} delete(File) -> delete_int({?DRV, []}, File). delete(Port, File) when is_port(Port) -> delete_int(Port, File). delete_int(Port, File) -> drv_command(Port, [?FILE_DELETE, File, 0]). %% rename/{2,3} rename(From, To) -> rename_int({?DRV, []}, From, To). rename(Port, From, To) when is_port(Port) -> rename_int(Port, From, To). rename_int(Port, From, To) -> drv_command(Port, [?FILE_RENAME, From, 0, To, 0]). %% make_dir/{1,2} make_dir(Dir) -> make_dir_int({?DRV, []}, Dir). make_dir(Port, Dir) when is_port(Port) -> make_dir_int(Port, Dir). make_dir_int(Port, Dir) -> drv_command(Port, [?FILE_MKDIR, Dir, 0]). %% del_dir/{1,2} del_dir(Dir) -> del_dir_int({?DRV, []}, Dir). del_dir(Port, Dir) when is_port(Port) -> del_dir_int(Port, Dir). del_dir_int(Port, Dir) -> drv_command(Port, [?FILE_RMDIR, Dir, 0]). %% read_file_info/{1,2} read_file_info(File) -> read_file_info_int({?DRV, []}, File). read_file_info(Port, File) when is_port(Port) -> read_file_info_int(Port, File). read_file_info_int(Port, File) -> drv_command(Port, [?FILE_FSTAT, File, 0]). %% altname/{1,2} altname(File) -> altname_int({?DRV, []}, File). altname(Port, File) when is_port(Port) -> altname_int(Port, File). altname_int(Port, File) -> drv_command(Port, [?FILE_ALTNAME, File, 0]). %% write_file_info/{2,3} write_file_info(File, Info) -> write_file_info_int({?DRV, []}, File, Info). write_file_info(Port, File, Info) when is_port(Port) -> write_file_info_int(Port, File, Info). write_file_info_int(Port, File, #file_info{mode=Mode, uid=Uid, gid=Gid, atime=Atime0, mtime=Mtime0, ctime=Ctime}) -> {Atime, Mtime} = case {Atime0, Mtime0} of {undefined, Mtime0} -> {erlang:localtime(), Mtime0}; {Atime0, undefined} -> {Atime0, Atime0}; Complete -> Complete end, drv_command(Port, [?FILE_WRITE_INFO, int_to_bytes(Mode), int_to_bytes(Uid), int_to_bytes(Gid), date_to_bytes(Atime), date_to_bytes(Mtime), date_to_bytes(Ctime), File, 0]). %% make_link/{2,3} make_link(Old, New) -> make_link_int({?DRV, []}, Old, New). make_link(Port, Old, New) when is_port(Port) -> make_link_int(Port, Old, New). make_link_int(Port, Old, New) -> drv_command(Port, [?FILE_LINK, Old, 0, New, 0]). %% make_symlink/{2,3} make_symlink(Old, New) -> make_symlink_int({?DRV, []}, Old, New). make_symlink(Port, Old, New) when is_port(Port) -> make_symlink_int(Port, Old, New). make_symlink_int(Port, Old, New) -> drv_command(Port, [?FILE_SYMLINK, Old, 0, New, 0]). %% read_link/{2,3} read_link(Link) -> read_link_int({?DRV, []}, Link). read_link(Port, Link) when is_port(Port) -> read_link_int(Port, Link). read_link_int(Port, Link) -> drv_command(Port, [?FILE_READLINK, Link, 0]). %% read_link_info/{2,3} read_link_info(Link) -> read_link_info_int({?DRV, []}, Link). read_link_info(Port, Link) when is_port(Port) -> read_link_info_int(Port, Link). read_link_info_int(Port, Link) -> drv_command(Port, [?FILE_LSTAT, Link, 0]). %% list_dir/{1,2} list_dir(Dir) -> list_dir_int({?DRV, []}, Dir). list_dir(Port, Dir) when is_port(Port) -> list_dir_int(Port, Dir). list_dir_int(Port, Dir) -> drv_command(Port, [?FILE_READDIR, Dir, 0], []). %%%----------------------------------------------------------------- %%% Functions to communicate with the driver %% Opens a driver port and converts any problems into {error, emfile}. %% Returns {ok, Port} when succesful. drv_open(Driver, Portopts) -> try erlang:open_port({spawn, Driver}, Portopts) of Port -> {ok, Port} catch error:Reason -> {error,Reason} end. %% Closes a port in a safe way. Returns ok. drv_close(Port) -> try erlang:port_close(Port) catch error:_ -> ok end, receive %% Ugly workaround in case the caller==owner traps exits {'EXIT', Port, _Reason} -> ok after 0 -> ok end. %% Issues a command to a port and gets the response. %% If Port is {Driver, Portopts} a port is first opened and %% then closed after the result has been received. %% Returns {ok, Result} or {error, Reason}. drv_command_raw(Port, Command) -> drv_command(Port, Command, false, undefined). drv_command(Port, Command) -> drv_command(Port, Command, undefined). drv_command(Port, Command, R) when is_binary(Command) -> drv_command(Port, Command, true, R); drv_command(Port, Command, R) -> try erlang:iolist_to_binary(Command) of Bin -> drv_command(Port, Bin, true, R) catch error:Reason -> {error, Reason} end. drv_command(Port, Command, Validated, R) when is_port(Port) -> try erlang:port_command(Port, Command) of true -> drv_get_response(Port, R) catch %% If the Command is valid, knowing that the port is a port, %% a badarg error must mean it is a dead port, that is: %% a currently invalid filehandle, -> einval, not badarg. error:badarg when Validated -> {error, einval}; error:badarg -> try erlang:iolist_size(Command) of _ -> % Valid {error, einval} catch error:_ -> {error, badarg} end; error:Reason -> {error, Reason} end; drv_command({Driver, Portopts}, Command, Validated, R) -> case drv_open(Driver, Portopts) of {ok, Port} -> Result = drv_command(Port, Command, Validated, R), drv_close(Port), Result; Error -> Error end. %% Receives the response from a driver port. %% Returns: {ok, ListOrBinary}|{error, Reason} drv_get_response(Port, R) when is_list(R) -> case drv_get_response(Port) of ok -> {ok, R}; {ok, Name} -> drv_get_response(Port, [Name|R]); Error -> Error end; drv_get_response(Port, _) -> drv_get_response(Port). drv_get_response(Port) -> erlang:bump_reductions(100), receive {Port, {data, [Response|Rest] = Data}} -> try translate_response(Response, Rest) catch error:Reason -> {error, {bad_response_from_port, Data, {Reason, erlang:get_stacktrace()}}} end; {'EXIT', Port, Reason} -> {error, {port_died, Reason}} end. %%%----------------------------------------------------------------- %%% Utility functions. %% Converts a list of mode atoms into an mode word for the driver. %% Returns {Mode, Portopts, Setopts} where Portopts is a list of %% options for erlang:open_port/2 and Setopts is a list of %% setopt commands to send to the port, or error Reason upon failure. open_mode(List) when is_list(List) -> case open_mode(List, 0, [], []) of {Mode, Portopts, Setopts} when Mode band (?EFILE_MODE_READ bor ?EFILE_MODE_WRITE) =:= 0 -> {Mode bor ?EFILE_MODE_READ, Portopts, Setopts}; Other -> Other end. open_mode([raw|Rest], Mode, Portopts, Setopts) -> open_mode(Rest, Mode, Portopts, Setopts); open_mode([read|Rest], Mode, Portopts, Setopts) -> open_mode(Rest, Mode bor ?EFILE_MODE_READ, Portopts, Setopts); open_mode([write|Rest], Mode, Portopts, Setopts) -> open_mode(Rest, Mode bor ?EFILE_MODE_WRITE, Portopts, Setopts); open_mode([binary|Rest], Mode, Portopts, Setopts) -> open_mode(Rest, Mode, [binary | Portopts], Setopts); open_mode([compressed|Rest], Mode, Portopts, Setopts) -> open_mode(Rest, Mode bor ?EFILE_COMPRESSED, Portopts, Setopts); open_mode([append|Rest], Mode, Portopts, Setopts) -> open_mode(Rest, Mode bor ?EFILE_MODE_APPEND bor ?EFILE_MODE_WRITE, Portopts, Setopts); open_mode([delayed_write|Rest], Mode, Portopts, Setopts) -> open_mode([{delayed_write, 64*1024, 2000}|Rest], Mode, Portopts, Setopts); open_mode([{delayed_write, Size, Delay}|Rest], Mode, Portopts, Setopts) when is_integer(Size), 0 =< Size, is_integer(Delay), 0 =< Delay -> if Size < ?LARGEFILESIZE, Delay < 1 bsl 64 -> open_mode(Rest, Mode, Portopts, [<<?FILE_SETOPT, ?FILE_OPT_DELAYED_WRITE, Size:64, Delay:64>> | Setopts]); true -> einval end; open_mode([read_ahead|Rest], Mode, Portopts, Setopts) -> open_mode([{read_ahead, 64*1024}|Rest], Mode, Portopts, Setopts); open_mode([{read_ahead, Size}|Rest], Mode, Portopts, Setopts) when is_integer(Size), 0 =< Size -> if Size < ?LARGEFILESIZE -> open_mode(Rest, Mode, Portopts, [<<?FILE_SETOPT, ?FILE_OPT_READ_AHEAD, Size:64>> | Setopts]); true -> einval end; open_mode([], Mode, Portopts, Setopts) -> {Mode, reverse(Portopts), reverse(Setopts)}; open_mode(_, _Mode, _Portopts, _Setopts) -> badarg. %% Converts a position tuple {bof, X} | {cur, X} | {eof, X} into %% {Offset, OriginCode} for the driver. %% Returns badarg upon failure. lseek_position(Pos) when is_integer(Pos) -> lseek_position({bof, Pos}); lseek_position(bof) -> lseek_position({bof, 0}); lseek_position(cur) -> lseek_position({cur, 0}); lseek_position(eof) -> lseek_position({eof, 0}); lseek_position({bof, Offset}) when is_integer(Offset) -> {Offset, ?EFILE_SEEK_SET}; lseek_position({cur, Offset}) when is_integer(Offset) -> {Offset, ?EFILE_SEEK_CUR}; lseek_position({eof, Offset}) when is_integer(Offset) -> {Offset, ?EFILE_SEEK_END}; lseek_position(_) -> badarg. %% Translates the response from the driver into %% {ok, Result} or {error, Reason}. translate_response(?FILE_RESP_OK, []) -> ok; translate_response(?FILE_RESP_OK, Data) -> {ok, Data}; translate_response(?FILE_RESP_ERROR, List) when is_list(List) -> {error, list_to_atom(List)}; translate_response(?FILE_RESP_NUMBER, List) -> {N, []} = get_uint64(List), {ok, N}; translate_response(?FILE_RESP_DATA, List) -> {N, Data} = get_uint64(List), {ok, {N, Data}}; translate_response(?FILE_RESP_INFO, List) when is_list(List) -> {ok, transform_info_ints(get_uint32s(List))}; translate_response(?FILE_RESP_NUMERR, L0) -> {N, L1} = get_uint64(L0), {error, {N, list_to_atom(L1)}}; translate_response(?FILE_RESP_LDATA, List) -> {ok, transform_ldata(List)}; translate_response(?FILE_RESP_N2DATA, <<Offset:64, 0:64, Size:64>>) -> {ok, {Size, Offset, eof}}; translate_response(?FILE_RESP_N2DATA, [<<Offset:64, 0:64, Size:64>> | <<>>]) -> {ok, {Size, Offset, eof}}; translate_response(?FILE_RESP_N2DATA = X, [<<_:64, 0:64, _:64>> | _] = Data) -> {error, {bad_response_from_port, [X | Data]}}; translate_response(?FILE_RESP_N2DATA = X, [<<_:64, _:64, _:64>> | <<>>] = Data) -> {error, {bad_response_from_port, [X | Data]}}; translate_response(?FILE_RESP_N2DATA, [<<Offset:64, _ReadSize:64, Size:64>> | D]) -> {ok, {Size, Offset, D}}; translate_response(?FILE_RESP_N2DATA = X, L0) when is_list(L0) -> {Offset, L1} = get_uint64(L0), {ReadSize, L2} = get_uint64(L1), {Size, L3} = get_uint64(L2), case {ReadSize, L3} of {0, []} -> {ok, {Size, Offset, eof}}; {0, _} -> {error, {bad_response_from_port, [X | L0]}}; {_, []} -> {error, {bad_response_from_port, [X | L0]}}; _ -> {ok, {Size, Offset, L3}} end; translate_response(?FILE_RESP_EOF, []) -> eof; translate_response(X, Data) -> {error, {bad_response_from_port, [X | Data]}}. transform_info_ints(Ints) -> [HighSize, LowSize, Type|Tail0] = Ints, Size = HighSize * 16#100000000 + LowSize, [Ay, Am, Ad, Ah, Ami, As|Tail1] = Tail0, [My, Mm, Md, Mh, Mmi, Ms|Tail2] = Tail1, [Cy, Cm, Cd, Ch, Cmi, Cs|Tail3] = Tail2, [Mode, Links, Major, Minor, Inode, Uid, Gid, Access] = Tail3, #file_info { size = Size, type = file_type(Type), access = file_access(Access), atime = {{Ay, Am, Ad}, {Ah, Ami, As}}, mtime = {{My, Mm, Md}, {Mh, Mmi, Ms}}, ctime = {{Cy, Cm, Cd}, {Ch, Cmi, Cs}}, mode = Mode, links = Links, major_device = Major, minor_device = Minor, inode = Inode, uid = Uid, gid = Gid}. file_type(1) -> device; file_type(2) -> directory; file_type(3) -> regular; file_type(4) -> symlink; file_type(_) -> other. file_access(0) -> none; file_access(1) -> write; file_access(2) -> read; file_access(3) -> read_write. int_to_bytes(Int) when is_integer(Int) -> <<Int:32>>; int_to_bytes(undefined) -> <<-1:32>>. date_to_bytes(undefined) -> <<-1:32, -1:32, -1:32, -1:32, -1:32, -1:32>>; date_to_bytes({{Y, Mon, D}, {H, Min, S}}) -> <<Y:32, Mon:32, D:32, H:32, Min:32, S:32>>. % uint64([[X1, X2, X3, X4] = Y1 | [X5, X6, X7, X8] = Y2]) -> % (uint32(Y1) bsl 32) bor uint32(Y2). % uint64(X1, X2, X3, X4, X5, X6, X7, X8) -> % (uint32(X1, X2, X3, X4) bsl 32) bor uint32(X5, X6, X7, X8). % uint32([X1,X2,X3,X4]) -> % (X1 bsl 24) bor (X2 bsl 16) bor (X3 bsl 8) bor X4. uint32(X1,X2,X3,X4) -> (X1 bsl 24) bor (X2 bsl 16) bor (X3 bsl 8) bor X4. get_uint64(L0) -> {X1, L1} = get_uint32(L0), {X2, L2} = get_uint32(L1), {(X1 bsl 32) bor X2, L2}. get_uint32([X1,X2,X3,X4|List]) -> {(((((X1 bsl 8) bor X2) bsl 8) bor X3) bsl 8) bor X4, List}. get_uint32s([X1,X2,X3,X4|Tail]) -> [uint32(X1,X2,X3,X4) | get_uint32s(Tail)]; get_uint32s([]) -> []. %% Binary mode transform_ldata(<<0:32, 0:32>>) -> []; transform_ldata([<<0:32, N:32, Sizes/binary>> | Datas]) -> transform_ldata(N, Sizes, Datas, []); %% List mode transform_ldata([_,_,_,_,_,_,_,_|_] = L0) -> {0, L1} = get_uint32(L0), {N, L2} = get_uint32(L1), transform_ldata(N, L2, []). %% List mode transform_ldata(0, List, Sizes) -> transform_ldata(0, List, reverse(Sizes), []); transform_ldata(N, L0, Sizes) -> {Size, L1} = get_uint64(L0), transform_ldata(N-1, L1, [Size | Sizes]). %% Binary mode transform_ldata(1, <<0:64>>, <<>>, R) -> reverse(R, [eof]); transform_ldata(1, <<Size:64>>, Data, R) when byte_size(Data) =:= Size -> reverse(R, [Data]); transform_ldata(N, <<0:64, Sizes/binary>>, [<<>> | Datas], R) -> transform_ldata(N-1, Sizes, Datas, [eof | R]); transform_ldata(N, <<Size:64, Sizes/binary>>, [Data | Datas], R) when byte_size(Data) =:= Size -> transform_ldata(N-1, Sizes, Datas, [Data | R]); %% List mode transform_ldata(0, [], [], R) -> reverse(R); transform_ldata(0, List, [0 | Sizes], R) -> transform_ldata(0, List, Sizes, [eof | R]); transform_ldata(0, List, [Size | Sizes], R) -> {Front, Rear} = lists_split(List, Size), transform_ldata(0, Rear, Sizes, [Front | R]). lists_split(List, 0) when is_list(List) -> {[], List}; lists_split(List, N) when is_list(List), is_integer(N), N < 0 -> erlang:error(badarg, [List, N]); lists_split(List, N) when is_list(List), is_integer(N) -> case lists_split(List, N, []) of premature_end_of_list -> erlang:error(badarg, [List, N]); Result -> Result end. lists_split(List, 0, Rev) -> {reverse(Rev), List}; lists_split([], _, _) -> premature_end_of_list; lists_split([Hd | Tl], N, Rev) -> lists_split(Tl, N-1, [Hd | Rev]). %% We KNOW that lists:reverse/2 is a BIF. reverse(X) -> lists:reverse(X, []). reverse(L, T) -> lists:reverse(L, T).