%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2016. 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%
%%
-module(snmpc_tok).
%% c(snmpc_tok).
%%----------------------------------------------------------------------
%% Generic (?) Tokenizer.
%%----------------------------------------------------------------------
%% Token: {Category, Line, Value}|{Category, Line}
%% (Category == <KeyWord> ==> 2-tuple (otherwise 3-tuple)
%% Category: integer | quote | string
%% | variable | atom | <keyword> | <single_char>
%%----------------------------------------------------------------------
%% API
-export([start_link/2, stop/1, get_token/1, get_all_tokens/1, tokenize/2]).
%% Internal exports
-export([null_get_line/0, format_error/1, terminate/2, handle_call/3, init/1,
test/0]).
-include("snmpc_lib.hrl").
%%----------------------------------------------------------------------
%% Reserved_words: list of KeyWords. Example: ['IF', 'BEGIN', ..., 'GOTO']
%% Options: list of Option
%% Option: {file, <filename>},
%% or: {get_line_function, {Mod, Func, Arg} (default io, get_line, [Fid])},
%% get_line_function shall behave as io:get_line.
%% {print_lineno, L}
%% Returns: {ok, Pid} | {error, Reason}
%%----------------------------------------------------------------------
start_link(Reserved_words, Options) ->
case lists:keysearch(file, 1, Options) of
{value, {file, Filename}} ->
case file:open(Filename, [read]) of
{ok, Fid} ->
gen_server:start_link(?MODULE,
{Reserved_words, Options,
{io, get_line, [Fid, prompt]}}, []);
Error ->
Str = format_error({"Cannot open file '~s' (~800p).~n",
[Filename, Error]}),
{error,Str}
end;
false ->
MFA = case lists:keysearch(get_line_function, 1, Options) of
{value, {get_line_function, {M, F, A}}} ->
{M,F,A};
false -> {?MODULE, null_get_line, []}
end,
gen_server:start_link(?MODULE,{Reserved_words,Options,MFA}, [])
end.
%%--------------------------------------------------
%% Returns:
%% {ok, [Token], LineNo} | {eof, LineNo} | {error, Error_description, Endline}
%% For more information, see manual page for yecc (and its requirements on a
%% tokenizer).
%%--------------------------------------------------
get_token(TokPid) ->
V = gen_server:call(TokPid, get_token, infinity),
%% io:format("tok:~w~n", [V]),
V.
get_all_tokens(TokPid) ->
V = gen_server:call(TokPid, get_all_tokens, infinity),
%% io:format("tok:~w~n", [V]),
V.
%%--------------------------------------------------
%% Returns: {ok, Tokens, EndLine} | {error, Error_description, Endline}
%% Comment: Tokeniser must be started since all options reside in
%% the process dictionary of the tokeniser process.
%%--------------------------------------------------
tokenize(TokPid, String) ->
gen_server:call(TokPid, {tokenize, String}, infinity).
stop(TokPid) ->
gen_server:call(TokPid,stop, infinity).
%%----------------------------------------------------------------------
%% Implementation
%%----------------------------------------------------------------------
insert_keywords_into_ets(_DB, []) -> done;
insert_keywords_into_ets(DB, [Word | T]) ->
ets:insert(DB, {Word, reserved_word}),
insert_keywords_into_ets(DB, T).
reserved_word(X) ->
case ets:lookup(get(db), X) of
[{X, reserved_word}] ->
true;
_ ->
false
end.
%% If you only need to tokenize strings
null_get_line() -> eof.
format_error({Format, Data}) ->
io_lib:format(lists:append("Tokeniser error: ", Format), Data).
test() ->
start_link(['AUGMENTS','BEGIN','CONTACT-INFO','DEFINITIONS','DEFVAL',
'DESCRIPTION','DISPLAY-HINT','END','IDENTIFIER','IMPLIED',
'INDEX','INTEGER','LAST-UPDATED','MAX-ACCESS','MODULE-IDENTITY',
'NOTIFICATION-TYPE','OBJECT','OBJECT-IDENTITY','OBJECT-TYPE',
'OBJECTS','ORGANIZATION','REFERENCE','REVISION',
'SIZE','STATUS','SYNTAX','TEXTUAL-CONVENTION','UNITS',
'current','deprecated','not-accessible','obsolete',
'read-create','read-only','read-write', 'IMPORTS', 'FROM',
'MODULE-COMPLIANCE',
'AGENT-CAPABILITIES',
'PRODUCT-RELEASE',
'SUPPORTS',
'INCLUDES',
'DisplayString',
'PhysAddress',
'MacAddress',
'TruthValue',
'TestAndIncr',
'AutonomousType',
'InstancePointer',
'VariablePointer',
'RowPointer',
'RowStatus',
'TimeStamp',
'TimeInterval',
'DateAndTime',
'StorageType',
'TDomain',
'TAddress'],
[{file, "modemmib.mib"}]).
init({Reserved_words, Options, GetLineMFA}) ->
put(get_line_function,GetLineMFA),
put(print_lineno,
case lists:keysearch(print_lineno, 1, Options) of
{value, {print_lineno, L}} -> L;
false -> undefined
end),
DB = ets:new(reserved_words, [set, private]),
insert_keywords_into_ets(DB, Reserved_words),
put(db, DB),
put(line, 0),
{ok, ""}.
getLine() ->
OldLine = put(line, 1 + get(line)),
{M,F,A} = get(get_line_function),
case get(print_lineno) of
undefined -> true;
X -> case OldLine rem X of
0 -> io:format('~w..',[OldLine]);
_ -> true
end
end,
apply(M,F,A).
%% You can only do this when no file is open.
handle_call({tokenizeString, String}, _From, "") ->
{reply, safe_tokenize_whole_string(String), ""};
handle_call(get_token, _From, String) ->
{ReplyToken, RestChars} = safe_tokenise(String),
{reply, ReplyToken, RestChars};
handle_call(get_all_tokens, _From, String) ->
Toks = get_all_tokens(String,[]),
{reply, Toks, []};
handle_call(stop, _From, String) ->
{stop, normal, ok, String}.
terminate(_Reason, _State) ->
ok.
%% ErrorInfo = {ErrorLine, Module, ErrorDescriptor}
%% will be used as
%% apply(Module, format_error, [ErrorDescriptor]). shall return a string.
%% Returns a reply
tokenize_whole_string(eof) -> [];
tokenize_whole_string(String) ->
{Token, RestChars} = tokenise(String),
[Token | tokenize_whole_string(RestChars)].
safe_tokenize_whole_string(String) ->
case catch tokenize_whole_string(String) of
{error, ErrorInfo} -> {error, ErrorInfo, get(line)};
Tokens -> {ok, Tokens, get(line)}
end.
%% throw({error, {get(line), ?MODULE, "Unexpected eof~n"}}).
%% Returns: {ReplyToken, NewState}
safe_tokenise(eof) -> {{eof, get(line)}, eof};
safe_tokenise(Chars) when is_list(Chars) ->
case catch tokenise(Chars) of
{error, ErrorInfo} -> {{error, ErrorInfo, get(line)}, {[], eof}};
{Token, RestChars} when is_tuple(Token) ->
{{ok, [Token], get(line)}, RestChars}
end.
get_all_tokens(eof,Toks) ->
lists:reverse(Toks);
get_all_tokens(Str,Toks) ->
case catch tokenise(Str) of
{error, ErrorInfo} -> {error, ErrorInfo};
{Token, RestChars} when is_tuple(Token) ->
%% ?vtrace("get_all_tokens -> Token: ~p", [Token]),
get_all_tokens(RestChars, [Token|Toks])
end.
%%--------------------------------------------------
%% Returns: {Token, Rest}
%%--------------------------------------------------
tokenise([H|T]) when ($a =< H) andalso (H =< $z) ->
get_name(atom, [H], T);
tokenise([H|T]) when ($A =< H) andalso (H =< $Z) ->
get_name(variable, [H], T);
tokenise([$:,$:,$=|T]) ->
{{'::=', get(line)}, T};
tokenise([$-,$-|T]) ->
tokenise(skip_comment(T));
tokenise([$-,H|T]) when ($0 =< H ) andalso (H =< $9) ->
{Val, Rest} = get_integer(T, [H]),
{{integer, get(line), -1 * Val}, Rest};
tokenise([H|T]) when ($0 =< H) andalso (H =< $9) ->
{Val, Rest} = get_integer(T, [H]),
{{integer, get(line), Val}, Rest};
tokenise([$"|T]) ->
collect_string($", T, []);
tokenise([$'|T]) ->
collect_string($', T, []);
%% Read away white spaces
tokenise([9| T]) -> tokenise(T);
tokenise([10| T]) -> tokenise(T);
tokenise([13| T]) -> tokenise(T);
tokenise([32| T]) -> tokenise(T);
%% Handle singe characters like { } [ ] + = ...
tokenise([Ch | T]) ->
Atm = list_to_atom([Ch]),
{{Atm, get(line)}, T};
tokenise([]) ->
tokenise(getLine());
tokenise(eof) ->
{{'$end', get(line)}, eof}.
collect_string($", [$"|T],BackwardsStr) ->
{{string, get(line), BackwardsStr}, T};
collect_string($', [$'|T],BackwardsStr) ->
{{quote, get(line), BackwardsStr}, T};
collect_string(StopChar, [Ch|T], Str) ->
collect_string(StopChar,T,[Ch|Str]);
collect_string(StopChar, [],Str) ->
collect_string(StopChar, getLine(), Str);
collect_string(StopChar, eof, Str) ->
throw({error, {get(line), ?MODULE,
{"Missing ~s in string:~n \"~s\"~n",
[[StopChar], lists:reverse(Str)]}}}).
get_name(Category, Name, [Char|T]) ->
case isInName(Char) of
true ->
get_name(Category, [Char|Name], T);
false ->
makeNameRespons(Category, Name, [Char | T])
end;
get_name(Category, Name, []) ->
makeNameRespons(Category, Name, []).
makeNameRespons(Category, Name, RestChars) ->
Atm = list_to_atom(lists:reverse(Name)),
case reserved_word(Atm) of
true -> {{Atm, get(line)}, RestChars};
false -> {{Category, get(line), Atm}, RestChars}
end.
isInName($-) -> true;
isInName(Ch) -> isalnum(Ch).
isalnum(H) when ($A =< H) andalso (H =< $Z) ->
true;
isalnum(H) when ($a =< H) andalso (H =< $z) ->
true;
isalnum(H) when ($0 =< H) andalso (H =< $9) ->
true;
isalnum(_) ->
false.
isdigit(H) when ($0 =< H) andalso (H =< $9) ->
true;
isdigit(_) ->
false.
get_integer([H|T], "0") ->
case isdigit(H) of
true ->
throw({error, {get(line), ?MODULE,
{"Unexpected ~w~n",
[list_to_atom([H])]}}});
false ->
{0, [H|T]}
end;
get_integer([H|T], L) ->
case isdigit(H) of
true ->
get_integer(T, [H|L]);
false ->
{list_to_integer(lists:reverse(L)), [H|T]}
end;
get_integer([], L) ->
{list_to_integer(lists:reverse(L)), []}.
%%--------------------------------------------------
%% ASN.1 type of comments. "--" is comment to eoln or next "--"
%%--------------------------------------------------
skip_comment([]) ->
[];
skip_comment([$-,$-|T]) ->
T;
skip_comment([_|T]) ->
skip_comment(T).
