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Diffstat (limited to 'src/couch_inets/tftp_file.erl')
| -rw-r--r-- | src/couch_inets/tftp_file.erl | 338 |
1 files changed, 338 insertions, 0 deletions
diff --git a/src/couch_inets/tftp_file.erl b/src/couch_inets/tftp_file.erl new file mode 100644 index 00000000..03e54047 --- /dev/null +++ b/src/couch_inets/tftp_file.erl @@ -0,0 +1,338 @@ +%%%------------------------------------------------------------------- +%%% File : tft_file.erl +%%% Author : Hakan Mattsson <hakan@erix.ericsson.se> +%%% Description : +%%% +%%% Created : 24 May 2004 by Hakan Mattsson <hakan@erix.ericsson.se> +%%%------------------------------------------------------------------- + +-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. |