aboutsummaryrefslogtreecommitdiffstats
path: root/lib/stdlib/src/erl_tar.erl
diff options
context:
space:
mode:
authorHans Nilsson <[email protected]>2014-11-10 17:09:25 +0100
committerHans Nilsson <[email protected]>2014-11-18 14:48:16 +0100
commitb2171f6bf65c5897d37103afec102fa565bc134e (patch)
tree8968f14919aec0e2c3e4008079ca27a17924bb9f /lib/stdlib/src/erl_tar.erl
parent9366932892711cc4cce7a54b1e098e6d5c3db468 (diff)
downloadotp-b2171f6bf65c5897d37103afec102fa565bc134e.tar.gz
otp-b2171f6bf65c5897d37103afec102fa565bc134e.tar.bz2
otp-b2171f6bf65c5897d37103afec102fa565bc134e.zip
erl_tar: Extend api to define own storage media access functions.
The reason for this is a requirement on enabling ssh_sftp to write a tar file on the server. This new api function is used by ssh_sftp:open_tar/3,4.
Diffstat (limited to 'lib/stdlib/src/erl_tar.erl')
-rw-r--r--lib/stdlib/src/erl_tar.erl93
1 files changed, 76 insertions, 17 deletions
diff --git a/lib/stdlib/src/erl_tar.erl b/lib/stdlib/src/erl_tar.erl
index acf7a5cd40..ab6223c0fe 100644
--- a/lib/stdlib/src/erl_tar.erl
+++ b/lib/stdlib/src/erl_tar.erl
@@ -22,7 +22,7 @@
%% Purpose: Unix tar (tape archive) utility.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
--export([create/2, create/3, extract/1, extract/2, table/1, table/2,
+-export([init/3, create/2, create/3, extract/1, extract/2, table/1, table/2,
open/2, close/1, add/3, add/4,
t/1, tt/1, format_error/1]).
@@ -30,10 +30,16 @@
-record(add_opts,
{read_info, % Fun to use for read file/link info.
+ chunk_size = 0, % For file reading when sending to sftp. 0=do not chunk
verbose = false :: boolean()}). % Verbose on/off.
%% Opens a tar archive.
+init(UsrHandle, AccessMode, Fun) when is_function(Fun,2) ->
+ {ok, {AccessMode,{UsrHandle,Fun}}}.
+
+%%%================================================================
+%%% The open function with friends is to keep the file and binary api of this module
open(Name, Mode) ->
case open_mode(Mode) of
{ok, Access, Raw, Opts} ->
@@ -46,27 +52,37 @@ open1({binary,Bin}, read, _Raw, Opts) ->
case file:open(Bin, [ram,binary,read]) of
{ok,File} ->
_ = [ram_file:uncompress(File) || Opts =:= [compressed]],
- {ok,{read,File}};
+ init(File,read,file_fun());
Error ->
Error
end;
open1({file, Fd}, read, _Raw, _Opts) ->
- {ok, {read, Fd}};
+ init(Fd, read, file_fun());
open1(Name, Access, Raw, Opts) ->
case file:open(Name, Raw ++ [binary, Access|Opts]) of
{ok, File} ->
- {ok, {Access, File}};
+ init(File, Access, file_fun());
{error, Reason} ->
{error, {Name, Reason}}
end.
+file_fun() ->
+ fun(write, {Fd,Data}) -> file:write(Fd, Data);
+ (position, {Fd,Pos}) -> file:position(Fd, Pos);
+ (read2, {Fd,Size}) -> file:read(Fd,Size);
+ (close, Fd) -> file:close(Fd)
+ end.
+
+%%% End of file and binary api (except for open_mode/1 downwards
+%%%================================================================
+
%% Closes a tar archive.
close({read, File}) ->
- ok = file:close(File);
+ ok = do_close(File);
close({write, File}) ->
PadResult = pad_file(File),
- ok = file:close(File),
+ ok = do_close(File),
PadResult;
close(_) ->
{error, einval}.
@@ -75,7 +91,6 @@ close(_) ->
add(File, Name, Options) ->
add(File, Name, Name, Options).
-
add({write, File}, Name, NameInArchive, Options) ->
Opts = #add_opts{read_info=fun(F) -> file:read_link_info(F) end},
add1(File, Name, NameInArchive, add_opts(Options, Opts));
@@ -88,6 +103,8 @@ add_opts([dereference|T], Opts) ->
add_opts(T, Opts#add_opts{read_info=fun(F) -> file:read_file_info(F) end});
add_opts([verbose|T], Opts) ->
add_opts(T, Opts#add_opts{verbose=true});
+add_opts([{chunks,N}|T], Opts) ->
+ add_opts(T, Opts#add_opts{chunk_size=N});
add_opts([_|T], Opts) ->
add_opts(T, Opts);
add_opts([], Opts) ->
@@ -321,16 +338,46 @@ add1(TarFile, Name, NameInArchive, Opts) ->
{error, {Name, Reason}}
end.
+add1(Tar, Name, Header, chunked, Options) ->
+ add_verbose(Options, "a ~ts [chunked ", [Name]),
+ try
+ ok = do_write(Tar, Header),
+ {ok,D} = file:open(Name, [read,binary]),
+ {ok,NumBytes} = add_read_write_chunks(D, Tar, Options#add_opts.chunk_size, 0, Options),
+ _ = file:close(D),
+ ok = do_write(Tar, padding(NumBytes,?record_size))
+ of
+ ok ->
+ add_verbose(Options, "~n", []),
+ ok
+ catch
+ error:{badmatch,{error,Error}} ->
+ add_verbose(Options, "~n", []),
+ {error,{Name,Error}}
+ end;
add1(Tar, Name, Header, Bin, Options) ->
add_verbose(Options, "a ~ts~n", [Name]),
- file:write(Tar, [Header, Bin, padding(byte_size(Bin), ?record_size)]).
+ do_write(Tar, [Header, Bin, padding(byte_size(Bin), ?record_size)]).
+
+add_read_write_chunks(D, Tar, ChunkSize, SumNumBytes, Options) ->
+ case file:read(D, ChunkSize) of
+ {ok,Bin} ->
+ ok = do_write(Tar, Bin),
+ add_verbose(Options, ".", []),
+ add_read_write_chunks(D, Tar, ChunkSize, SumNumBytes+byte_size(Bin), Options);
+ eof ->
+ add_verbose(Options, "]", []),
+ {ok,SumNumBytes};
+ Other ->
+ Other
+ end.
add_directory(TarFile, DirName, NameInArchive, Info, Options) ->
case file:list_dir(DirName) of
{ok, []} ->
add_verbose(Options, "a ~ts~n", [DirName]),
Header = create_header(NameInArchive, Info),
- file:write(TarFile, Header);
+ do_write(TarFile, Header);
{ok, Files} ->
Add = fun (File) ->
add1(TarFile,
@@ -396,7 +443,7 @@ to_string(Str0, Count) ->
%% Pads out end of file.
pad_file(File) ->
- {ok,Position} = file:position(File, {cur,0}),
+ {ok,Position} = do_position(File, {cur,0}),
%% There must be at least two zero records at the end.
Fill = case ?block_size - (Position rem ?block_size) of
Fill0 when Fill0 < 2*?record_size ->
@@ -407,7 +454,7 @@ pad_file(File) ->
%% Large enough.
Fill0
end,
- file:write(File, zeroes(Fill)).
+ do_write(File, zeroes(Fill)).
split_filename(Name) when length(Name) =< ?th_name_len ->
{"", Name};
@@ -500,7 +547,7 @@ foldl_read(TarName, Fun, Accu, Opts) ->
Ok ->
Ok
end,
- ok = file:close(File),
+ ok = do_close(File),
Result;
Error ->
Error
@@ -559,7 +606,7 @@ check_extract(Name, #read_opts{files=Files}) ->
ordsets:is_element(Name, Files).
get_header(File) ->
- case file:read(File, ?record_size) of
+ case do_read(File, ?record_size) of
eof ->
throw({error,eof});
{ok, Bin} when is_binary(Bin) ->
@@ -690,7 +737,7 @@ get_element(File, #tar_header{size = 0}) ->
skip_to_next(File),
{ok,<<>>};
get_element(File, #tar_header{size = Size}) ->
- case file:read(File, Size) of
+ case do_read(File, Size) of
{ok,Bin}=Res when byte_size(Bin) =:= Size ->
skip_to_next(File),
Res;
@@ -880,7 +927,7 @@ skip(File, Size) ->
%% Note: There is no point in handling failure to get the current position
%% in the file. If it doesn't work, something serious is wrong.
Amount = ((Size + ?record_size - 1) div ?record_size) * ?record_size,
- {ok,_} = file:position(File, {cur, Amount}),
+ {ok,_} = do_position(File, {cur, Amount}),
ok.
%% Skips to the next record in the file.
@@ -888,9 +935,9 @@ skip(File, Size) ->
skip_to_next(File) ->
%% Note: There is no point in handling failure to get the current position
%% in the file. If it doesn't work, something serious is wrong.
- {ok, Position} = file:position(File, {cur, 0}),
+ {ok, Position} = do_position(File, {cur, 0}),
NewPosition = ((Position + ?record_size - 1) div ?record_size) * ?record_size,
- {ok,NewPosition} = file:position(File, NewPosition),
+ {ok,NewPosition} = do_position(File, NewPosition),
ok.
%% Prints the message on if the verbose option is given.
@@ -916,6 +963,9 @@ posix_to_erlang_time(Sec) ->
read_file_and_info(Name, Opts) ->
ReadInfo = Opts#add_opts.read_info,
case ReadInfo(Name) of
+ {ok,Info} when Info#file_info.type =:= regular,
+ Opts#add_opts.chunk_size>0 ->
+ {ok,chunked,Info};
{ok,Info} when Info#file_info.type =:= regular ->
case file:read_file(Name) of
{ok,Bin} ->
@@ -962,3 +1012,12 @@ open_mode([], Access, Raw, Opts) ->
{ok, Access, Raw, Opts};
open_mode(_, _, _, _) ->
{error, einval}.
+
+%%%================================================================
+do_write({UsrHandle,Fun}, Data) -> Fun(write,{UsrHandle,Data}).
+
+do_position({UsrHandle,Fun}, Pos) -> Fun(position,{UsrHandle,Pos}).
+
+do_read({UsrHandle,Fun}, Len) -> Fun(read2,{UsrHandle,Len}).
+
+do_close({UsrHandle,Fun}) -> Fun(close,UsrHandle).