%% %% %CopyrightBegin% %% %% Copyright Ericsson AB 2001-2011. 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(ram_file_SUITE). -export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1, init_per_group/2,end_per_group/2, %% init/1, fini/1, init_per_testcase/2, end_per_testcase/2]). -export([open_modes/1, open_old_modes/1, pread_pwrite/1, position/1, truncate/1, sync/1, get_set_file/1, compress/1, uuencode/1, large_file_errors/1, large_file_light/1, large_file_heavy/1]). -include_lib("test_server/include/test_server.hrl"). -include_lib("kernel/include/file.hrl"). -define(FILE_MODULE, file). % Name of module to test -define(RAM_FILE_MODULE, ram_file). % Name of module to test %%-------------------------------------------------------------------------- suite() -> [{ct_hooks,[ts_install_cth]}]. all() -> [open_modes, open_old_modes, pread_pwrite, position, truncate, sync, get_set_file, compress, uuencode, large_file_errors, large_file_light, large_file_heavy]. groups() -> []. init_per_suite(Config) -> Config. end_per_suite(_Config) -> ok. init_per_group(_GroupName, Config) -> Config. end_per_group(_GroupName, Config) -> Config. init_per_testcase(Func, Config) when is_atom(Func), is_list(Config) -> Time = case Func of large_file_heavy -> ?t:minutes(5); _ -> ?t:seconds(10) end, Dog = ?t:timetrap(Time), %% error_logger:info_msg("~p:~p *****~n", [?MODULE, Func]), [{watchdog, Dog} | Config]. end_per_testcase(_Func, Config) -> %% error_logger:info_msg("~p:~p END *****~n", [?MODULE, Func]), Dog = ?config(watchdog, Config), ?t:timetrap_cancel(Dog). %%-------------------------------------------------------------------------- %% Test suites open_modes(suite) -> []; open_modes(doc) -> ["Test that the basic read, write and binary options works for open/2."]; open_modes(Config) when is_list(Config) -> ?line Str1 = "The quick brown fox ", ?line Str2 = "jumps over a lazy dog ", ?line Str = Str1 ++ Str2, ?line Bin1 = list_to_binary(Str1), ?line Bin2 = list_to_binary(Str2), ?line Bin = list_to_binary(Str), %% open_read_write(?FILE_MODULE, Str1, [ram, read, write], Str2), open_read(?FILE_MODULE, Str, [ram]), open_read_write(?FILE_MODULE, Bin1, [ram, binary, read, write], Bin2), open_read(?FILE_MODULE, Bin, [ram, binary, read]), %% ok. open_old_modes(suite) -> []; open_old_modes(doc) -> ["Test that the old style read, write and binary options ", "works for open/2."]; open_old_modes(Config) when is_list(Config) -> ?line Str1 = "The quick brown fox ", ?line Str2 = "jumps over a lazy dog ", ?line Str = Str1 ++ Str2, ?line Bin1 = list_to_binary(Str1), ?line Bin2 = list_to_binary(Str2), ?line Bin = list_to_binary(Str), %% open_read_write(?RAM_FILE_MODULE, Str1, read_write, Str2), open_read(?RAM_FILE_MODULE, Str, read), open_read_write(?RAM_FILE_MODULE, Bin1, {binary, read_write}, Bin2), open_read(?RAM_FILE_MODULE, Bin, {binary, read}), %% ok. open_read_write(Module, Data1, Options, Data2) -> ?line io:format("~p:open_read_write(~p, ~p, ~p, ~p)~n", [?MODULE, Module, Data1, Options, Data2]), %% ?line Size1 = sizeof(Data1), ?line Size2 = sizeof(Data2), ?line Data = append(Data1, Data2), ?line Size = Size1 + Size2, %% ?line {ok, Fd} = Module:open(Data1, Options), ?line {ok, Data1} = Module:read(Fd, Size1), ?line eof = Module:read(Fd, 1), ?line {ok, Zero} = Module:read(Fd, 0), ?line 0 = sizeof(Zero), ?line ok = Module:write(Fd, Data2), ?line {ok, 0} = Module:position(Fd, bof), ?line {ok, Data} = Module:read(Fd, Size), ?line eof = Module:read(Fd, 1), ?line {ok, Zero} = Module:read(Fd, 0), ?line ok = Module:close(Fd), %% ?line ok. open_read(Module, Data, Options) -> ?line io:format("~p:open_read(~p, ~p, ~p)~n", [?MODULE, Module, Data, Options]), %% ?line Size = sizeof(Data), %% ?line {ok, Fd} = Module:open(Data, Options), ?line {ok, Data} = Module:read(Fd, Size), ?line eof = Module:read(Fd, 1), ?line {ok, Zero} = Module:read(Fd, 0), ?line 0 = sizeof(Zero), ?line {error, ebadf} = Module:write(Fd, Data), ?line {ok, 0} = Module:position(Fd, bof), ?line {ok, Data} = Module:read(Fd, Size), ?line eof = Module:read(Fd, 1), ?line {ok, Zero} = Module:read(Fd, 0), ?line ok = Module:close(Fd), %% ?line ok. pread_pwrite(suite) -> []; pread_pwrite(doc) -> ["Test that pread/2,3 and pwrite/2,3 works."]; pread_pwrite(Config) when is_list(Config) -> ?line Str = "Flygande b�ckaziner s�ka hwila p� mjuqa tuvor x", ?line Bin = list_to_binary(Str), %% pread_pwrite_test(?FILE_MODULE, Str, [ram, read, write]), pread_pwrite_test(?FILE_MODULE, Bin, [ram, binary, read, write]), pread_pwrite_test(?RAM_FILE_MODULE, Str, [read, write]), pread_pwrite_test(?RAM_FILE_MODULE, Bin, {binary, read_write}), %% ok. pread_pwrite_test(Module, Data, Options) -> ?line io:format("~p:pread_pwrite_test(~p, ~p, ~p)~n", [?MODULE, Module, Data, Options]), %% ?line Size = sizeof(Data), %% ?line {ok, Fd} = Module:open([], Options), ?line ok = Module:pwrite(Fd, 0, Data), ?line {ok, Data} = Module:pread(Fd, 0, Size+1), ?line eof = Module:pread(Fd, Size+1, 1), ?line {ok, Zero} = Module:pread(Fd, Size+1, 0), ?line 0 = sizeof(Zero), ?line ok = Module:pwrite(Fd, [{0, Data}, {Size+17, Data}]), ?line {ok, [Data, eof, Data, Zero]} = Module:pread(Fd, [{Size+17, Size+1}, {2*Size+17+1, 1}, {0, Size}, {2*Size+17+1, 0}]), ?line ok = Module:close(Fd), %% ?line ok. position(suite) -> []; position(doc) -> ["Test that position/2 works."]; position(Config) when is_list(Config) -> ?line Str = "Att vara eller icke vara, det �r fr�gan. ", ?line Bin = list_to_binary(Str), %% position_test(?FILE_MODULE, Str, [ram, read]), position_test(?FILE_MODULE, Bin, [ram, binary]), position_test(?RAM_FILE_MODULE, Str, [read]), position_test(?RAM_FILE_MODULE, Bin, {binary, read}), %% ok. position_test(Module, Data, Options) -> ?line io:format("~p:position_test(~p, ~p, ~p)~n", [?MODULE, Module, Data, Options]), %% ?line Size = sizeof(Data), ?line Size_7 = Size+7, %% ?line Slice_0_2 = slice(Data, 0, 2), ?line Slice_0_3 = slice(Data, 0, 3), ?line Slice_2_5 = slice(Data, 2, 5), ?line Slice_3_4 = slice(Data, 3, 4), ?line Slice_5 = slice(Data, 5, Size), %% ?line {ok, Fd} = Module:open(Data, Options), %% ?line io:format("CUR positions"), ?line {ok, Slice_0_2} = Module:read(Fd, 2), ?line {ok, 2} = Module:position(Fd, cur), ?line {ok, Slice_2_5} = Module:read(Fd, 5), ?line {ok, 3} = Module:position(Fd, {cur, -4}), ?line {ok, Slice_3_4} = Module:read(Fd, 4), ?line {ok, 0} = Module:position(Fd, {cur, -7}), ?line {ok, Slice_0_3} = Module:read(Fd, 3), ?line {ok, 0} = Module:position(Fd, {cur, -3}), ?line {error, einval} = Module:position(Fd, {cur, -1}), ?line {ok, 0} = Module:position(Fd, 0), ?line {ok, 2} = Module:position(Fd, {cur, 2}), ?line {ok, Slice_2_5} = Module:read(Fd, 5), ?line {ok, Size_7} = Module:position(Fd, {cur, Size}), ?line {ok, Zero} = Module:read(Fd, 0), ?line 0 = sizeof(Zero), ?line eof = Module:read(Fd, 1), %% ?line io:format("Absolute and BOF positions"), ?line {ok, Size} = Module:position(Fd, Size), ?line eof = Module:read(Fd, 1), ?line {ok, 5} = Module:position(Fd, 5), ?line {ok, Slice_5} = Module:read(Fd, Size), ?line {ok, 2} = Module:position(Fd, {bof, 2}), ?line {ok, Slice_2_5} = Module:read(Fd, 5), ?line {ok, 3} = Module:position(Fd, 3), ?line {ok, Slice_3_4} = Module:read(Fd, 4), ?line {ok, 0} = Module:position(Fd, bof), ?line {ok, Slice_0_2} = Module:read(Fd, 2), ?line {ok, Size_7} = Module:position(Fd, {bof, Size_7}), ?line {ok, Zero} = Module:read(Fd, 0), %% ?line io:format("EOF positions"), ?line {ok, Size} = Module:position(Fd, eof), ?line eof = Module:read(Fd, 1), ?line {ok, 5} = Module:position(Fd, {eof, -Size+5}), ?line {ok, Slice_5} = Module:read(Fd, Size), ?line {ok, 2} = Module:position(Fd, {eof, -Size+2}), ?line {ok, Slice_2_5} = Module:read(Fd, 5), ?line {ok, 3} = Module:position(Fd, {eof, -Size+3}), ?line {ok, Slice_3_4} = Module:read(Fd, 4), ?line {ok, 0} = Module:position(Fd, {eof, -Size}), ?line {ok, Slice_0_2} = Module:read(Fd, 2), ?line {ok, Size_7} = Module:position(Fd, {eof, 7}), ?line {ok, Zero} = Module:read(Fd, 0), ?line eof = Module:read(Fd, 1), %% ?line ok. truncate(suite) -> []; truncate(doc) -> ["Test that truncate/1 works."]; truncate(Config) when is_list(Config) -> ?line Str = "M�n �dlare att lida och f�rdraga " ++ "ett bittert �des stygn av pilar, ", ?line Bin = list_to_binary(Str), %% ok = truncate_test(?FILE_MODULE, Str, [ram, read, write]), ok = truncate_test(?FILE_MODULE, Bin, [ram, binary, read, write]), ok = truncate_test(?RAM_FILE_MODULE, Str, read_write), ok = truncate_test(?RAM_FILE_MODULE, Bin, [binary, read, write]), %% {error, eacces} = truncate_test(?FILE_MODULE, Str, [ram]), {error, eacces} = truncate_test(?FILE_MODULE, Bin, [ram, binary, read]), {error, eacces} = truncate_test(?RAM_FILE_MODULE, Str, read), {error, eacces} = truncate_test(?RAM_FILE_MODULE, Bin, {binary, read}), %% ok. truncate_test(Module, Data, Options) -> ?line io:format("~p:truncate_test(~p, ~p, ~p)~n", [?MODULE, Module, Data, Options]), %% ?line Size = sizeof(Data), ?line Size1 = Size-2, ?line Data1 = slice(Data, 0, Size1), %% ?line {ok, Fd} = Module:open(Data, Options), ?line {ok, Size1} = Module:position(Fd, Size1), ?line case Module:truncate(Fd) of ok -> ?line {ok, 0} = Module:position(Fd, 0), ?line {ok, Data1} = Module:read(Fd, Size), ?line ok = Module:close(Fd), ?line ok; Error -> ?line ok = Module:close(Fd), ?line Error end. sync(suite) -> []; sync(doc) -> ["Test that sync/1 at least does not crash."]; sync(Config) when is_list(Config) -> ?line Str = "�n att ta till vapen mot ett hav av kval. ", ?line Bin = list_to_binary(Str), %% sync_test(?FILE_MODULE, Str, [ram, read, write]), sync_test(?FILE_MODULE, Bin, [ram, binary, read, write]), sync_test(?RAM_FILE_MODULE, Str, read_write), sync_test(?RAM_FILE_MODULE, Bin, [binary, read, write]), %% sync_test(?FILE_MODULE, Str, [ram]), sync_test(?FILE_MODULE, Bin, [ram, binary, read]), sync_test(?RAM_FILE_MODULE, Str, read), sync_test(?RAM_FILE_MODULE, Bin, {binary, read}), %% ok. sync_test(Module, Data, Options) -> ?line io:format("~p:sync_test(~p, ~p, ~p)~n", [?MODULE, Module, Data, Options]), %% ?line Size = sizeof(Data), %% ?line {ok, Fd} = Module:open(Data, Options), ?line ok = Module:sync(Fd), ?line {ok, Data} = Module:read(Fd, Size+1), ?line ok. get_set_file(suite) -> []; get_set_file(doc) -> ["Tests get_file/1, set_file/2, get_file_close/1 and get_size/1."]; get_set_file(Config) when is_list(Config) -> %% These two strings should not be of equal length. ?line Str = "N�r h�gan nord blir sn�bet�ckt, ", ?line Str2 = "f�r alla harar byta dr�kt. ", ?line Bin = list_to_binary(Str), ?line Bin2 = list_to_binary(Str2), %% ok = get_set_file_test(Str, read_write, Str2), ok = get_set_file_test(Bin, [binary, read, write], Bin2), ok = get_set_file_test(Str, read, Str2), ok = get_set_file_test(Bin, [binary, read], Bin2), %% ok. get_set_file_test(Data, Options, Data2) -> ?line io:format("~p:get_set_file_test(~p, ~p, ~p)~n", [?MODULE, Data, Options, Data2]), %% ?line Size = sizeof(Data), ?line Size2 = sizeof(Data2), %% ?line {ok, Fd} = ?RAM_FILE_MODULE:open(Data, Options), ?line {ok, Size} = ?RAM_FILE_MODULE:get_size(Fd), ?line {ok, Data} = ?RAM_FILE_MODULE:get_file(Fd), ?line {ok, Data} = ?RAM_FILE_MODULE:get_file_close(Fd), ?line {error, einval} = ?RAM_FILE_MODULE:get_size(Fd), ?line {ok, Fd2} = ?RAM_FILE_MODULE:open(Data, Options), ?line case ?RAM_FILE_MODULE:set_file(Fd2, Data2) of {ok, Size2} -> ?line {ok, Size2} = ?RAM_FILE_MODULE:get_size(Fd2), ?line {ok, Data2} = ?RAM_FILE_MODULE:get_file(Fd2), ?line {ok, Data2} = ?RAM_FILE_MODULE:get_file_close(Fd2), ?line ok; {error, _} = Error -> ?line {ok, Data} = ?RAM_FILE_MODULE:get_file_close(Fd2), ?line Error end. compress(suite) -> []; compress(doc) -> ["Test that compress/1 and uncompress/1 works."]; compress(Config) when is_list(Config) -> ?line Data = ?config(data_dir, Config), ?line Real = filename:join(Data, "realmen.html"), ?line RealGz = filename:join(Data, "realmen.html.gz"), %% %% Uncompress test %% ?line {ok, FdReal} = ?FILE_MODULE:open(Real, []), ?line {ok, Fd} = ?FILE_MODULE:open([], [ram, read, write]), ?line {ok, FdRealGz} = ?FILE_MODULE:open(RealGz, []), %% ?line {ok, SzGz} = ?FILE_MODULE:copy(FdRealGz, Fd), ?line {ok, Sz} = ?RAM_FILE_MODULE:uncompress(Fd), ?line {ok, 0} = ?FILE_MODULE:position(Fd, bof), ?line true = compare(FdReal, Fd), %% ?line true = (SzGz =< Sz), %% %% Compress and uncompress test %% ?line {ok, 0} = ?FILE_MODULE:position(FdReal, bof), ?line {ok, 0} = ?FILE_MODULE:position(Fd, bof), ?line ok = ?FILE_MODULE:truncate(Fd), ?line {ok, Sz} = ?FILE_MODULE:copy(FdReal, Fd), ?line {ok, SzGz} = ?RAM_FILE_MODULE:compress(Fd), ?line {ok, Sz} = ?RAM_FILE_MODULE:uncompress(Fd), ?line {ok, 0} = ?FILE_MODULE:position(Fd, bof), ?line {ok, 0} = ?FILE_MODULE:position(FdReal, bof), ?line true = compare(FdReal, Fd), %% ?line ok = ?FILE_MODULE:close(FdReal), ?line ok = ?FILE_MODULE:close(Fd), ?line ok = ?FILE_MODULE:close(FdRealGz), %% Test uncompressing data that will be expanded many times. ?line Huge = iolist_to_binary(mk_42(18)), ?line HugeSize = byte_size(Huge), ?line HugeGz = zlib:gzip(Huge), ?line {ok,HugeFd} = ?FILE_MODULE:open([], [ram,read,write,binary]), ?line ok = ?FILE_MODULE:write(HugeFd, HugeGz), ?line {ok,HugeSize} = ?RAM_FILE_MODULE:uncompress(HugeFd), ?line {ok,0} = ?FILE_MODULE:position(HugeFd, bof), ?line {ok,Huge} = ?FILE_MODULE:read(HugeFd, HugeSize), %% Uncompressing again should do nothing. ?line {ok,HugeSize} = ?RAM_FILE_MODULE:uncompress(HugeFd), ?line {ok,0} = ?FILE_MODULE:position(HugeFd, bof), ?line {ok,Huge} = ?FILE_MODULE:read(HugeFd, HugeSize), ?line ok = ?FILE_MODULE:close(HugeFd), ok. mk_42(0) -> [42]; mk_42(N) -> B = mk_42(N-1), [B|B]. uuencode(suite) -> []; uuencode(doc) -> ["Test that uuencode/1 and uudecode/1 works."]; uuencode(Config) when is_list(Config) -> ?line Data = ?config(data_dir, Config), ?line Real = filename:join(Data, "realmen.html"), ?line RealUu = filename:join(Data, "realmen.html.uu"), %% %% Uudecode test %% ?line {ok, FdReal} = ?FILE_MODULE:open(Real, []), ?line {ok, Fd} = ?FILE_MODULE:open([], [ram, read, write]), ?line {ok, FdRealUu} = ?FILE_MODULE:open(RealUu, []), %% ?line {ok, SzUu} = ?FILE_MODULE:copy(FdRealUu, Fd), ?line {ok, Sz} = ?RAM_FILE_MODULE:uudecode(Fd), ?line true = (Sz =< SzUu), ?line {ok, 0} = ?FILE_MODULE:position(Fd, bof), ?line true = compare(FdReal, Fd), %% %% Uuencode and decode test %% F = fun(Offs) -> Size = Sz - Offs, ?line {ok, Offs} = ?FILE_MODULE:position(FdReal, {bof,Offs}), ?line {ok, 0} = ?FILE_MODULE:position(Fd, bof), ?line ok = ?FILE_MODULE:truncate(Fd), ?line {ok, Size} = ?FILE_MODULE:copy(FdReal, Fd), ?line {ok, SizeUu} = ?RAM_FILE_MODULE:uuencode(Fd), ?line true = (Size =< SizeUu), ?line {ok, Size} = ?RAM_FILE_MODULE:uudecode(Fd), ?line {ok, Offs} = ?FILE_MODULE:position(FdReal, {bof,Offs}), ?line {ok, 0} = ?FILE_MODULE:position(Fd, bof), ?line true = compare(FdReal, Fd) end, lists:foreach(F, lists:seq(0,Sz-1, 43)), ?line ok = ?FILE_MODULE:close(FdReal), ?line ok = ?FILE_MODULE:close(Fd), ?line ok = ?FILE_MODULE:close(FdRealUu), %% ok. large_file_errors(suite) -> []; large_file_errors(doc) -> ["Test error checking of large file offsets."]; large_file_errors(Config) when is_list(Config) -> ?line TwoGig = 1 bsl 31, ?line {ok,Fd} = ?RAM_FILE_MODULE:open("1234567890", [read,write]), ?line {error, einval} = ?FILE_MODULE:read(Fd, TwoGig), ?line {error, badarg} = ?FILE_MODULE:read(Fd, -1), ?line {error, einval} = ?FILE_MODULE:position(Fd, {bof,TwoGig}), ?line {error, einval} = ?FILE_MODULE:position(Fd, {bof,-TwoGig-1}), ?line {error, einval} = ?FILE_MODULE:position(Fd, {bof,-1}), ?line {error, einval} = ?FILE_MODULE:position(Fd, {cur,TwoGig}), ?line {error, einval} = ?FILE_MODULE:position(Fd, {cur,-TwoGig-1}), ?line {error, einval} = ?FILE_MODULE:position(Fd, {eof,TwoGig}), ?line {error, einval} = ?FILE_MODULE:position(Fd, {eof,-TwoGig-1}), ?line {error, einval} = ?FILE_MODULE:pread(Fd, TwoGig, 1), ?line {error, einval} = ?FILE_MODULE:pread(Fd, -TwoGig-1, 1), ?line {error, einval} = ?FILE_MODULE:pread(Fd, -1, 1), ?line {error, einval} = ?FILE_MODULE:pwrite(Fd, TwoGig, "@"), ?line {error, einval} = ?FILE_MODULE:pwrite(Fd, -TwoGig-1, "@"), ?line {error, einval} = ?FILE_MODULE:pwrite(Fd, -1, "@"), ?line {error, einval} = ?FILE_MODULE:pread(Fd, TwoGig, 0), ?line {error, einval} = ?FILE_MODULE:pread(Fd, -TwoGig-1, 0), ?line {error, einval} = ?FILE_MODULE:pread(Fd, -1, 0), ?line ok = ?FILE_MODULE:close(Fd), ok. large_file_light(suite) -> []; large_file_light(doc) -> ["Test light operations on a \"large\" ram_file."]; large_file_light(Config) when is_list(Config) -> ?line PrivDir = ?config(priv_dir, Config), %% Marker for next test case that is to heavy to run in a suite. ?line ok = ?FILE_MODULE:write_file( filename:join(PrivDir, large_file_light), <<"TAG">>), %% ?line Data = "abcdefghijklmnopqrstuvwzyz", ?line Size = sizeof(Data), ?line Max = (1 bsl 31) - 1, ?line Max__1 = Max - 1, ?line {ok, Fd} = ?RAM_FILE_MODULE:open(Data, [read]), ?line {ok, Data} = ?FILE_MODULE:read(Fd, Size+1), ?line {ok, Max__1} = ?FILE_MODULE:position(Fd, {eof, Max-Size-1}), ?line eof = ?FILE_MODULE:read(Fd, 1), ?line {ok, Max} = ?FILE_MODULE:position(Fd, {bof, Max}), ?line {ok, Zero} = ?FILE_MODULE:read(Fd, 0), ?line 0 = sizeof(Zero), ?line eof = ?FILE_MODULE:read(Fd, 1), ?line eof = ?FILE_MODULE:pread(Fd, Max__1, 1), ?line {ok, Zero} = ?FILE_MODULE:pread(Fd, Max, 0), ?line eof = ?FILE_MODULE:pread(Fd, Max, 1), ok. large_file_heavy(suite) -> []; large_file_heavy(doc) -> ["Test operations on a maximum size (2 GByte - 1) ram_file."]; large_file_heavy(Config) when is_list(Config) -> ?line PrivDir = ?config(priv_dir, Config), %% Check previous test case marker. case ?FILE_MODULE:read_file_info( filename:join(PrivDir, large_file_light)) of {ok,_} -> {skipped,"Too heavy for casual testing!"}; _ -> do_large_file_heavy(Config) end. do_large_file_heavy(_Config) -> ?line Data = "qwertyuiopasdfghjklzxcvbnm", ?line Size = sizeof(Data), ?line Max = (1 bsl 31) - 1, ?line Max__1 = Max - 1, ?line Max__3 = Max - 3, ?line {ok, Fd} = ?RAM_FILE_MODULE:open(Data, [read,write]), ?line {ok, Data} = ?FILE_MODULE:read(Fd, Size+1), ?line {ok, Max} = ?FILE_MODULE:position(Fd, {eof, Max-Size}), ?line eof = ?FILE_MODULE:read(Fd, 1), ?line erlang:display({allocating,2,'GByte',please,be,patient,'...'}), ?line ok = ?FILE_MODULE:write(Fd, ""), ?line erlang:display({allocating,2,'GByte',succeeded}), ?line {ok, Max__1} = ?FILE_MODULE:position(Fd, {eof, -1}), ?line {ok, [0]} = ?FILE_MODULE:read(Fd, 1), ?line {ok, []} = ?FILE_MODULE:read(Fd, 0), ?line eof = ?FILE_MODULE:read(Fd, 1), ?line ok = ?FILE_MODULE:pwrite(Fd, Max-3, "TAG"), ?line {ok, Max} = ?FILE_MODULE:position(Fd, cur), ?line {ok, Max__3} = ?FILE_MODULE:position(Fd, {eof, -3}), ?line {ok, "TAG"} = ?FILE_MODULE:read(Fd, 3+1), ?line {ok, Max__3} = ?FILE_MODULE:position(Fd, {cur, -3}), ?line ok = ?FILE_MODULE:write(Fd, "tag"), ?line {ok, Max} = ?FILE_MODULE:position(Fd, cur), ?line {ok, 0} = ?FILE_MODULE:position(Fd, bof), ?line {ok, "tag"} = ?FILE_MODULE:pread(Fd, Max__3, 3+1), ?line {ok, 0} = ?FILE_MODULE:position(Fd, cur), ?line ok = ?FILE_MODULE:close(Fd), ok. %%-------------------------------------------------------------------------- %% Utility functions compare(FdA, FdB) -> Size = 65536, case {?FILE_MODULE:read(FdA, Size), ?FILE_MODULE:read(FdB, Size)} of {{error, _} = Error, _} -> Error; {_, {error, _} = Error} -> Error; {{ok, A}, {ok, B}} -> case compare_data(A, B) of true -> compare(FdA, FdB); false -> false end; {eof, eof} -> true; _ -> false end. compare_data(A, B) when is_list(A), is_list(B) -> list_to_binary(A) == list_to_binary(B); compare_data(A, B) when is_list(A), is_binary(B) -> list_to_binary(A) == B; compare_data(A, B) when is_binary(A), is_list(B) -> A == list_to_binary(B); compare_data(A, B) when is_binary(A), is_binary(B) -> A == B. sizeof(Data) when is_list(Data) -> length(Data); sizeof(Data) when is_binary(Data) -> byte_size(Data). append(Data1, Data2) when is_list(Data1), is_list(Data2) -> Data1 ++ Data2; append(Data1, Data2) when is_binary(Data1), is_binary(Data2) -> list_to_binary([Data1 | Data2]). slice(Data, Start, Length) when is_list(Data) -> lists:sublist(Data, Start+1, Length); slice(Data, Start, Length) when is_binary(Data) -> {_, Bin} = split_binary(Data, Start), if Length >= byte_size(Bin) -> Bin; true -> {B, _} = split_binary(Bin, Length), B end.