%%%------------------------------------------------------------------- %%% File : tft_file.erl %%% Author : Hakan Mattsson %%% Description : %%% %%% Created : 24 May 2004 by Hakan Mattsson %%%------------------------------------------------------------------- -module(tftp_file). %%%------------------------------------------------------------------- %%% Interface %%%------------------------------------------------------------------- -behaviour(tftp). -export([prepare/6, open/6, read/1, write/2, abort/3]). -export([prepare/5, open/5]). %%%------------------------------------------------------------------- %%% Defines %%%------------------------------------------------------------------- -include_lib("kernel/include/file.hrl"). -record(state, {access, filename, root_dir, options, blksize, fd, count, buffer}). %%------------------------------------------------------------------- %% prepare(Peer, Access, Filename, Mode, SuggestedOptions, InitialState) -> %% {ok, AcceptedOptions, NewState} | {error, Code, Text} %% %% Peer = {PeerType, PeerHost, PeerPort} %% PeerType = inet | inet6 %% PeerHost = ip_address() %% PeerPort = integer() %% Acess = read | write %% Filename = string() %% Mode = string() %% SuggestedOptions = [{Key, Value}] %% AcceptedOptions = [{Key, Value}] %% Key = string() %% Value = string() %% InitialState = [] | [{root_dir, string()}] %% NewState = term() %% Code = undef | enoent | eacces | enospc | %% badop | eexist | baduser | badopt | %% integer() %% Text = string() %% %% Prepares open of a file on the client side. %% %% Will be followed by a call to open/4 before any read/write access %% is performed. The AcceptedOptions will be sent to the server which %% will reply with those options that it accepts. The options that are %% accepted by the server will be forwarded to open/4 as SuggestedOptions. %% %% No new options may be added, but the ones that are present as %% SuggestedOptions may be omitted or replaced with new values %% in the AcceptedOptions. %%------------------------------------------------------------------- prepare(_Peer, Access, Filename, Mode, SuggestedOptions, Initial) -> %% Kept for backwards compatibility prepare(Access, Filename, Mode, SuggestedOptions, Initial). prepare(Access, Filename, Mode, SuggestedOptions, Initial) when is_list(Initial) -> %% Client side case catch handle_options(Access, Filename, Mode, SuggestedOptions, Initial) of {ok, Filename2, AcceptedOptions} -> State = #state{access = Access, filename = Filename2, options = AcceptedOptions, blksize = lookup_blksize(AcceptedOptions), count = 0, buffer = []}, {ok, AcceptedOptions, State}; {error, {Code, Text}} -> {error, {Code, Text}} end. %% --------------------------------------------------------- %% open(Peer, Access, Filename, Mode, SuggestedOptions, State) -> %% {ok, AcceptedOptions, NewState} | {error, Code, Text} %% %% Peer = {PeerType, PeerHost, PeerPort} %% PeerType = inet | inet6 %% PeerHost = ip_address() %% PeerPort = integer() %% Acess = read | write %% Filename = string() %% Mode = string() %% SuggestedOptions = [{Key, Value}] %% AcceptedOptions = [{Key, Value}] %% Key = string() %% Value = string() %% State = InitialState | #state{} %% InitialState = [] | [{root_dir, string()}] %% NewState = term() %% Code = undef | enoent | eacces | enospc | %% badop | eexist | baduser | badopt | %% integer() %% Text = string() %% %% Opens a file for read or write access. %% %% On the client side where the open/4 call has been preceeded by a %% call to prepare/4, all options must be accepted or rejected. %% On the server side, where there are no preceeding prepare/4 call, %% noo new options may be added, but the ones that are present as %% SuggestedOptions may be omitted or replaced with new values %% in the AcceptedOptions. %%------------------------------------------------------------------- open(_Peer, Access, Filename, Mode, SuggestedOptions, Initial) -> %% Kept for backwards compatibility open(Access, Filename, Mode, SuggestedOptions, Initial). open(Access, Filename, Mode, SuggestedOptions, Initial) when is_list(Initial) -> %% Server side case prepare(Access, Filename, Mode, SuggestedOptions, Initial) of {ok, AcceptedOptions, State} -> open(Access, Filename, Mode, AcceptedOptions, State); {error, {Code, Text}} -> {error, {Code, Text}} end; open(Access, Filename, Mode, NegotiatedOptions, State) when is_record(State, state) -> %% Both sides case catch handle_options(Access, Filename, Mode, NegotiatedOptions, State) of {ok, _Filename2, Options} when Options =:= NegotiatedOptions -> do_open(State); {error, {Code, Text}} -> {error, {Code, Text}} end. do_open(State) when is_record(State, state) -> case file:open(State#state.filename, file_options(State)) of {ok, Fd} -> {ok, State#state.options, State#state{fd = Fd}}; {error, Reason} when is_atom(Reason) -> {error, file_error(Reason)} end. file_options(State) -> case State#state.access of read -> [read, read_ahead, raw, binary]; write -> [write, delayed_write, raw, binary] end. file_error(Reason) when is_atom(Reason) -> Details = file:format_error(Reason), case Reason of eexist -> {Reason, Details}; enoent -> {Reason, Details}; eacces -> {Reason, Details}; eperm -> {eacces, Details}; enospc -> {Reason, Details}; _ -> {undef, Details ++ " (" ++ atom_to_list(Reason) ++ ")"} end. %%------------------------------------------------------------------- %% read(State) -> %% {more, Bin, NewState} | {last, Bin, FileSize} | {error, {Code, Text}} %% %% State = term() %% NewState = term() %% Bin = binary() %% FileSize = integer() %% Code = undef | enoent | eacces | enospc | %% badop | eexist | baduser | badopt | %% integer() %% Text = string() %% %% Reads a chunk from the file %% %% The file is automatically closed when the last chunk is read. %%------------------------------------------------------------------- read(#state{access = read} = State) -> BlkSize = State#state.blksize, case file:read(State#state.fd, BlkSize) of {ok, Bin} when is_binary(Bin), size(Bin) =:= BlkSize -> Count = State#state.count + size(Bin), {more, Bin, State#state{count = Count}}; {ok, Bin} when is_binary(Bin), size(Bin) < BlkSize -> file:close(State#state.fd), Count = State#state.count + size(Bin), {last, Bin, Count}; eof -> {last, <<>>, State#state.count}; {error, Reason} -> file:close(State#state.fd), {error, file_error(Reason)} end. %%------------------------------------------------------------------- %% write(Bin, State) -> %% {more, NewState} | {last, FileSize} | {error, {Code, Text}} %% %% State = term() %% NewState = term() %% Bin = binary() %% FileSize = integer() %% Code = undef | enoent | eacces | enospc | %% badop | eexist | baduser | badopt | %% integer() %% Text = string() %% %% Writes a chunk to the file %% %% The file is automatically closed when the last chunk is written %%------------------------------------------------------------------- write(Bin, #state{access = write} = State) when is_binary(Bin) -> Size = size(Bin), BlkSize = State#state.blksize, case file:write(State#state.fd, Bin) of ok when Size =:= BlkSize-> Count = State#state.count + Size, {more, State#state{count = Count}}; ok when Size < BlkSize-> file:close(State#state.fd), Count = State#state.count + Size, {last, Count}; {error, Reason} -> file:close(State#state.fd), file:delete(State#state.filename), {error, file_error(Reason)} end. %%------------------------------------------------------------------- %% abort(Code, Text, State) -> ok %% %% State = term() %% Code = undef | enoent | eacces | enospc | %% badop | eexist | baduser | badopt | %% badblk | integer() %% Text = string() %% %% Aborts the file transfer %%------------------------------------------------------------------- abort(_Code, _Text, #state{fd = Fd, access = Access} = State) -> file:close(Fd), case Access of write -> ok = file:delete(State#state.filename); read -> ok end. %%------------------------------------------------------------------- %% Process options %%------------------------------------------------------------------- handle_options(Access, Filename, Mode, Options, InitialState) when Mode =:= "octet" -> Filename2 = handle_filename(Filename, InitialState), Options2 = do_handle_options(Access, Filename2, Options), {ok, Filename2, Options2}; handle_options(_Access, _Filename, Mode, _Options, _InitialState) -> {error, {badop, "Illegal mode " ++ Mode}}. handle_filename(Filename, InitialState) when is_list(InitialState) -> case lists:keysearch(root_dir, 1, InitialState) of {value, {_, Dir}} -> case catch filename_join(Dir, Filename) of {'EXIT', _} -> throw({error, {badop, "Internal error. root_dir is not a string"}}); Filename2 -> Filename2 end; false -> Filename end; handle_filename(_Filename, State) when is_record(State, state) -> State#state.filename. filename_join(Dir, Filename) -> case filename:pathtype(Filename) of absolute -> [_ | RelFilename] = filename:split(Filename), filename:join([Dir, RelFilename]); _ -> filename:join([Dir, Filename]) end. do_handle_options(Access, Filename, [{Key, Val} | T]) -> case Key of "tsize" -> case Access of read when Val =:= "0" -> case file:read_file_info(Filename) of {ok, FI} -> Tsize = integer_to_list(FI#file_info.size), [{Key, Tsize} | do_handle_options(Access, Filename, T)]; {error, _} -> do_handle_options(Access, Filename, T) end; _ -> handle_integer(Access, Filename, Key, Val, T, 0, infinity) end; "blksize" -> handle_integer(Access, Filename, Key, Val, T, 8, 65464); "timeout" -> handle_integer(Access, Filename, Key, Val, T, 1, 255); _ -> do_handle_options(Access, Filename, T) end; do_handle_options(_Access, _Filename, []) -> []. handle_integer(Access, Filename, Key, Val, Options, Min, Max) -> case catch list_to_integer(Val) of {'EXIT', _} -> do_handle_options(Access, Filename, Options); Int when Int >= Min, Int =< Max -> [{Key, Val} | do_handle_options(Access, Filename, Options)]; Int when Int >= Min, Max =:= infinity -> [{Key, Val} | do_handle_options(Access, Filename, Options)]; _Int -> throw({error, {badopt, "Illegal " ++ Key ++ " value " ++ Val}}) end. lookup_blksize(Options) -> case lists:keysearch("blksize", 1, Options) of {value, {_, Val}} -> list_to_integer(Val); false -> 512 end.