aboutsummaryrefslogblamecommitdiffstats
path: root/lib/inets/src/http_server/mod_range.erl
blob: a0408cba79954bd9419e1f688748711b677cd9e7 (plain) (tree)
1
2
3
4
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419

                   
                                                        
















                                                                         
                               










































































































































































































































































































































































































                                                                               
%%
%% %CopyrightBegin%
%% 
%% Copyright Ericsson AB 2001-2010. 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(mod_range).
-export([do/1]).
-include("httpd.hrl").
-include("httpd_internal.hrl").
%% do

do(Info) ->
    ?DEBUG("do -> entry",[]),
    case Info#mod.method of
	"GET" ->
	    case proplists:get_value(status, Info#mod.data) of
		%% A status code has been generated!
		{_StatusCode,  _PhraseArgs, _Reason} ->
		    {proceed,Info#mod.data};
		%% No status code has been generated!
		undefined ->
		    case proplists:get_value(response, Info#mod.data) of
			%% No response has been generated!
			undefined ->
			    case proplists:get_value("range",
						     Info#mod.parsed_header) of
				undefined ->
				    %Not a range response
				    {proceed,Info#mod.data};
				Range ->
				    %%Control that there weren't a
				    %%if-range field that stopped The
				    %%range request in favor for the
				    %%whole file
				    case proplists:get_value(if_range,
							     Info#mod.data) of
					send_file ->
					    {proceed,Info#mod.data};
					_undefined ->
					    do_get_range(Info,Range)
				    end
			    end; 			
			%% A response has been generated or sent!
			_Response ->
			    {proceed, Info#mod.data}
		    end
	    end;
	%% Not a GET method!
	_ ->
	    {proceed,Info#mod.data}
    end.

do_get_range(Info,Ranges) ->
    ?DEBUG("do_get_range -> Request URI: ~p",[Info#mod.request_uri]), 
     Path = mod_alias:path(Info#mod.data, Info#mod.config_db, 
			  Info#mod.request_uri),
    {FileInfo, LastModified} = get_modification_date(Path),
    send_range_response(Path, Info, Ranges, FileInfo, LastModified).


send_range_response(Path, Info, Ranges, FileInfo, LastModified)->
    case parse_ranges(Ranges) of
	error->
	    ?ERROR("send_range_response-> Unparsable range request",[]),
	    {proceed,Info#mod.data};
	{multipart,RangeList}->
	    send_multi_range_response(Path, Info, RangeList);
	{Start,Stop}->
	    send_range_response(Path, Info, Start, Stop, FileInfo, 
				LastModified)
    end.
%%More than one range specified
%%Send a multipart reponse to the user
%
%%An example of an multipart range response

% HTTP/1.1 206 Partial Content
% Date:Wed 15 Nov 1995 04:08:23 GMT
% Last-modified:Wed 14 Nov 1995 04:08:23 GMT 
% Content-type: multipart/byteranges; boundary="SeparatorString" 
%
% --"SeparatorString"
% Content-Type: application/pdf
% Content-Range: bytes 500-600/1010
% .... The data..... 101 bytes
%
% --"SeparatorString"
% Content-Type: application/pdf
% Content-Range: bytes 700-1009/1010
% .... The data.....



send_multi_range_response(Path,Info,RangeList)->
    case file:open(Path, [raw,binary]) of
	{ok, FileDescriptor} ->
	    file:close(FileDescriptor),
	    ?DEBUG("send_multi_range_response -> FileDescriptor: ~p",
		   [FileDescriptor]),
	    Suffix = httpd_util:suffix(Path),
	    PartMimeType = httpd_util:lookup_mime_default(Info#mod.config_db,
							  Suffix,"text/plain"),
	    {FileInfo,  LastModified} = get_modification_date(Path),
	    case valid_ranges(RangeList,Path,FileInfo) of
		{ValidRanges,true}->
		    ?DEBUG("send_multi_range_response ->Ranges are valid:",[]),
		    %Apache breaks the standard by sending the size
		    %field in the Header.
		    Header = 
			[{code,206},
			 {content_type, "multipart/byteranges;boundary" 
			  "=RangeBoundarySeparator"}, 
			 {etag, httpd_util:create_etag(FileInfo)} | 
			 LastModified],
		    ?DEBUG("send_multi_range_response -> Valid Ranges: ~p",
			   [RagneList]),
		    Body = {fun send_multiranges/4,
			    [ValidRanges, Info, PartMimeType, Path]},
		    {proceed,[{response,
			       {response, Header, Body}} | Info#mod.data]};
		_ ->
		    {proceed, [{status, {416, "Range not valid",
					 bad_range_boundaries }}]}
	    end;
	{error, _Reason} ->
	    ?ERROR("do_get -> failed open file: ~p",[_Reason]),
	    {proceed,Info#mod.data}
    end.

send_multiranges(ValidRanges,Info,PartMimeType,Path)->    
    ?DEBUG("send_multiranges -> Start sending the ranges",[]),
    case file:open(Path, [raw,binary]) of
	{ok,FileDescriptor} ->
	    lists:foreach(fun(Range)->
				  send_multipart_start(Range,
						       Info,
						       PartMimeType,
						       FileDescriptor)
			  end,ValidRanges),
	    file:close(FileDescriptor),
	    %%Sends an end of the multipart
	    httpd_socket:deliver(Info#mod.socket_type,Info#mod.socket,
				 "\r\n--RangeBoundarySeparator--"),
	    sent;
	_ ->
	    close
    end.
   
send_multipart_start({{Start,End},{StartByte,EndByte,Size}},Info,
		     PartMimeType,FileDescriptor)
  when StartByte < Size ->
    PartHeader=["\r\n--RangeBoundarySeparator\r\n","Content-type: ",
		PartMimeType,"\r\n",
                "Content-Range:bytes=",integer_to_list(StartByte),"-",
		integer_to_list(EndByte),"/",
		integer_to_list(Size),"\r\n\r\n"],
    send_part_start(Info#mod.socket_type, Info#mod.socket, PartHeader,
		    FileDescriptor, Start, End);


send_multipart_start({{Start,End},{StartByte,EndByte,Size}}, Info,
		     PartMimeType, FileDescriptor)->
    PartHeader=["\r\n--RangeBoundarySeparator\r\n","Content-type: ",
		PartMimeType,"\r\n",
                "Content-Range:bytes=",integer_to_list(Size-(StartByte-Size)),
		"-",integer_to_list(EndByte),"/",
		integer_to_list(Size),"\r\n\r\n"],
    send_part_start(Info#mod.socket_type, Info#mod.socket, PartHeader,
		    FileDescriptor, Start, End).

send_part_start(SocketType, Socket, PartHeader, FileDescriptor, Start, End)->
    case httpd_socket:deliver(SocketType, Socket, PartHeader) of
	ok ->
	    send_part_start(SocketType,Socket,FileDescriptor,Start,End);
	_ ->
	    close
    end.    

send_range_response(Path, Info, Start, Stop, FileInfo, LastModified)->
    case file:open(Path, [raw,binary]) of
	{ok, FileDescriptor} ->
	    file:close(FileDescriptor),
	    ?DEBUG("send_range_response -> FileDescriptor: ~p",
		   [FileDescriptor]),
	    Suffix = httpd_util:suffix(Path),
	    MimeType = httpd_util:lookup_mime_default(Info#mod.config_db,
						      Suffix,"text/plain"),
	    Size = get_range_size(Start,Stop,FileInfo),
	    case valid_range(Start,Stop,FileInfo) of
		{true,StartByte,EndByte,TotByte}->
		    Head =[{code,206},{content_type, MimeType}, 
			   {etag, httpd_util:create_etag(FileInfo)},
			   {content_range,["bytes=",
					   integer_to_list(StartByte),"-",
					   integer_to_list(EndByte),"/",
					   integer_to_list(TotByte)]},
			   {content_length, Size} | LastModified],
		    BodyFunc = fun send_range_body/5,
		    Arg = [Info#mod.socket_type, 
			  Info#mod.socket, Path, Start, Stop], 
		    {proceed,[{response,{response ,Head,  {BodyFunc,Arg}}}|
			      Info#mod.data]};
		{false,Reason} ->
		    {proceed, [{status, {416, Reason, bad_range_boundaries }}]}
	    end;
	{error, _Reason} ->
	    ?ERROR("send_range_response -> failed open file: ~p",[_Reason]),
	    {proceed,Info#mod.data}
    end.


send_range_body(SocketType,Socket,Path,Start,End) ->
    ?DEBUG("mod_range -> send_range_body",[]),
    case file:open(Path, [raw,binary]) of
	{ok,FileDescriptor} ->
	    send_part_start(SocketType,Socket,FileDescriptor,Start,End),
	    file:close(FileDescriptor);
	_ ->
	    close
    end.

send_part_start(SocketType,Socket,FileDescriptor,Start,End) ->
    case Start of
	from_end ->
	    file:position(FileDescriptor,{eof,End}),
	    send_body(SocketType,Socket,FileDescriptor);
	from_start ->
	    file:position(FileDescriptor,{bof,End}),
	    send_body(SocketType,Socket,FileDescriptor);
	Byte when is_integer(Byte) ->
	    file:position(FileDescriptor,{bof,Start}),
	    send_part(SocketType,Socket,FileDescriptor,End)
    end,
    sent.


%%This function could replace send_body by calling it with Start=0 end
%%=FileSize But i gues it would be stupid when we look at performance
send_part(SocketType,Socket,FileDescriptor,End)->
    case file:position(FileDescriptor,{cur,0}) of
	{ok,NewPos} ->
	   if 
	       NewPos > End ->
		   ok;
	       true ->
		   Size = get_file_chunk_size(NewPos,End,?FILE_CHUNK_SIZE),
		   case file:read(FileDescriptor,Size) of
		       eof ->
			   ok;
		       {error, _Reason} ->
			   ok;
		       {ok,Binary} ->
			   case httpd_socket:deliver(SocketType,Socket,
						     Binary) of
			       socket_closed ->
				   ?LOG("send_range of body -> socket "   
					"closed while sending",[]),
				   socket_close;
			       _ ->
				   send_part(SocketType,Socket,
					     FileDescriptor,End)
			   end
		   end
	   end;
	_->
	    ok
    end.

%% validate that the range is in the limits of the file
valid_ranges(RangeList, _Path, FileInfo)->
    lists:mapfoldl(fun({Start,End},Acc)->
			case Acc of 
			    true ->
				case valid_range(Start,End,FileInfo) of
				    {true,StartB,EndB,Size}->
					{{{Start,End},
					  {StartB,EndB,Size}},true};
				    _ ->
					false
				end;
			    _ ->
				{false,false}
			end
		   end,true,RangeList).
				 
			      

valid_range(from_end,End,FileInfo)->
    Size=FileInfo#file_info.size,
    if
	End < Size ->
	    {true,(Size+End),Size-1,Size};
	true ->
	    false
    end;
valid_range(from_start,End,FileInfo)->
  Size=FileInfo#file_info.size,
    if
	End < Size ->
	    {true,End,Size-1,Size};
	true ->
	    false
    end;

valid_range(Start,End,FileInfo) when Start =< End ->
    case FileInfo#file_info.size of
	FileSize when Start< FileSize ->
	    case FileInfo#file_info.size of
		Size when End<Size ->
		    {true,Start,End,FileInfo#file_info.size};
		Size ->
		    {true,Start,Size-1,Size}
	    end;
	_->
	    {false,"The size of the range is negative"}
    end;
		      
valid_range(_Start,_End,_FileInfo)->
    {false,"Range starts out of file boundaries"}.
%% Find the modification date of the file
get_modification_date(Path)->
    case file:read_file_info(Path) of
	{ok, FileInfo0} ->
	    case (catch httpd_util:rfc1123_date(FileInfo0#file_info.mtime)) of
		Date when is_list(Date) ->
		    {FileInfo0, [{last_modified, Date}]};
		_ ->
		    {FileInfo0, []}
	    end;
	_ ->
	    {#file_info{}, []}
    end.

%Calculate the size of the chunk to read
	
get_file_chunk_size(Position, End, DefaultChunkSize) 
  when (Position+DefaultChunkSize) =< End ->
    DefaultChunkSize;
get_file_chunk_size(Position, End, _DefaultChunkSize) ->
    (End-Position) +1.



%Get the size of the range to send. Remember that
%A range is from startbyte up to endbyte which means that
%the nuber of byte in a range is (StartByte-EndByte)+1

get_range_size(from_end, Stop, _FileInfo)->
    integer_to_list(-1*Stop);

get_range_size(from_start, StartByte, FileInfo) ->
    integer_to_list((((FileInfo#file_info.size)-StartByte)));

get_range_size(StartByte, EndByte, _FileInfo) ->
    integer_to_list((EndByte-StartByte)+1).

parse_ranges("\bytes\=" ++ Ranges)->
    parse_ranges("bytes\=" ++ Ranges);
parse_ranges("bytes\=" ++ Ranges)->
    case string:tokens(Ranges,", ") of
       [Range] ->
	   parse_range(Range);
       [Range1|SplittedRanges]->
	   {multipart,lists:map(fun parse_range/1,[Range1|SplittedRanges])}
    end;
%Bad unit
parse_ranges(Ranges)->
    io:format("Bad Ranges : ~p",[Ranges]),
    error.
%Parse the range  specification from the request to {Start,End}
%Start=End : Numreric string | []

parse_range(Range)->
    format_range(split_range(Range,[],[])).
format_range({[],BytesFromEnd})->
    {from_end,-1*(list_to_integer(BytesFromEnd))};
format_range({StartByte,[]})->    
    {from_start,list_to_integer(StartByte)};
format_range({StartByte,EndByte})->        
    {list_to_integer(StartByte),list_to_integer(EndByte)}.
%Last case return the splitted range
split_range([],Current,Other)->
    {lists:reverse(Other),lists:reverse(Current)};

split_range([$-|Rest],Current,Other)->
    split_range(Rest,Other,Current);

split_range([N|Rest],Current,End) ->
    split_range(Rest,[N|Current],End).

send_body(SocketType,Socket,FileDescriptor) ->
    case file:read(FileDescriptor,?FILE_CHUNK_SIZE) of
	{ok,Binary} ->
	    ?DEBUG("send_body -> send another chunk: ~p",[size(Binary)]),
	    case httpd_socket:deliver(SocketType,Socket,Binary) of
		socket_closed ->
		    ?LOG("send_body -> socket closed while sending",[]),
		    socket_close;
		_ ->
		    send_body(SocketType,Socket,FileDescriptor)
	    end;
	eof ->
	    ?DEBUG("send_body -> done with this file",[]),
	    eof
    end.