| 1 |
---------------------------------------------------------------- |
| 2 |
-- ZLib for Ada thick binding. -- |
| 3 |
-- -- |
| 4 |
-- Copyright (C) 2002-2004 Dmitriy Anisimkov -- |
| 5 |
-- -- |
| 6 |
-- Open source license information is in the zlib.ads file. -- |
| 7 |
---------------------------------------------------------------- |
| 8 |
|
| 9 |
-- $Id: zlib.adb,v 1.31 2004/09/06 06:53:19 vagul Exp $ |
| 10 |
|
| 11 |
with Ada.Exceptions; |
| 12 |
with Ada.Unchecked_Conversion; |
| 13 |
with Ada.Unchecked_Deallocation; |
| 14 |
|
| 15 |
with Interfaces.C.Strings; |
| 16 |
|
| 17 |
with ZLib.Thin; |
| 18 |
|
| 19 |
package body ZLib is |
| 20 |
|
| 21 |
use type Thin.Int; |
| 22 |
|
| 23 |
type Z_Stream is new Thin.Z_Stream; |
| 24 |
|
| 25 |
type Return_Code_Enum is |
| 26 |
(OK, |
| 27 |
STREAM_END, |
| 28 |
NEED_DICT, |
| 29 |
ERRNO, |
| 30 |
STREAM_ERROR, |
| 31 |
DATA_ERROR, |
| 32 |
MEM_ERROR, |
| 33 |
BUF_ERROR, |
| 34 |
VERSION_ERROR); |
| 35 |
|
| 36 |
type Flate_Step_Function is access |
| 37 |
function (Strm : in Thin.Z_Streamp; Flush : in Thin.Int) return Thin.Int; |
| 38 |
pragma Convention (C, Flate_Step_Function); |
| 39 |
|
| 40 |
type Flate_End_Function is access |
| 41 |
function (Ctrm : in Thin.Z_Streamp) return Thin.Int; |
| 42 |
pragma Convention (C, Flate_End_Function); |
| 43 |
|
| 44 |
type Flate_Type is record |
| 45 |
Step : Flate_Step_Function; |
| 46 |
Done : Flate_End_Function; |
| 47 |
end record; |
| 48 |
|
| 49 |
subtype Footer_Array is Stream_Element_Array (1 .. 8); |
| 50 |
|
| 51 |
Simple_GZip_Header : constant Stream_Element_Array (1 .. 10) |
| 52 |
:= (16#1f#, 16#8b#, -- Magic header |
| 53 |
16#08#, -- Z_DEFLATED |
| 54 |
16#00#, -- Flags |
| 55 |
16#00#, 16#00#, 16#00#, 16#00#, -- Time |
| 56 |
16#00#, -- XFlags |
| 57 |
16#03# -- OS code |
| 58 |
); |
| 59 |
-- The simplest gzip header is not for informational, but just for |
| 60 |
-- gzip format compatibility. |
| 61 |
-- Note that some code below is using assumption |
| 62 |
-- Simple_GZip_Header'Last > Footer_Array'Last, so do not make |
| 63 |
-- Simple_GZip_Header'Last <= Footer_Array'Last. |
| 64 |
|
| 65 |
Return_Code : constant array (Thin.Int range <>) of Return_Code_Enum |
| 66 |
:= (0 => OK, |
| 67 |
1 => STREAM_END, |
| 68 |
2 => NEED_DICT, |
| 69 |
-1 => ERRNO, |
| 70 |
-2 => STREAM_ERROR, |
| 71 |
-3 => DATA_ERROR, |
| 72 |
-4 => MEM_ERROR, |
| 73 |
-5 => BUF_ERROR, |
| 74 |
-6 => VERSION_ERROR); |
| 75 |
|
| 76 |
Flate : constant array (Boolean) of Flate_Type |
| 77 |
:= (True => (Step => Thin.Deflate'Access, |
| 78 |
Done => Thin.DeflateEnd'Access), |
| 79 |
False => (Step => Thin.Inflate'Access, |
| 80 |
Done => Thin.InflateEnd'Access)); |
| 81 |
|
| 82 |
Flush_Finish : constant array (Boolean) of Flush_Mode |
| 83 |
:= (True => Finish, False => No_Flush); |
| 84 |
|
| 85 |
procedure Raise_Error (Stream : in Z_Stream); |
| 86 |
pragma Inline (Raise_Error); |
| 87 |
|
| 88 |
procedure Raise_Error (Message : in String); |
| 89 |
pragma Inline (Raise_Error); |
| 90 |
|
| 91 |
procedure Check_Error (Stream : in Z_Stream; Code : in Thin.Int); |
| 92 |
|
| 93 |
procedure Free is new Ada.Unchecked_Deallocation |
| 94 |
(Z_Stream, Z_Stream_Access); |
| 95 |
|
| 96 |
function To_Thin_Access is new Ada.Unchecked_Conversion |
| 97 |
(Z_Stream_Access, Thin.Z_Streamp); |
| 98 |
|
| 99 |
procedure Translate_GZip |
| 100 |
(Filter : in out Filter_Type; |
| 101 |
In_Data : in Ada.Streams.Stream_Element_Array; |
| 102 |
In_Last : out Ada.Streams.Stream_Element_Offset; |
| 103 |
Out_Data : out Ada.Streams.Stream_Element_Array; |
| 104 |
Out_Last : out Ada.Streams.Stream_Element_Offset; |
| 105 |
Flush : in Flush_Mode); |
| 106 |
-- Separate translate routine for make gzip header. |
| 107 |
|
| 108 |
procedure Translate_Auto |
| 109 |
(Filter : in out Filter_Type; |
| 110 |
In_Data : in Ada.Streams.Stream_Element_Array; |
| 111 |
In_Last : out Ada.Streams.Stream_Element_Offset; |
| 112 |
Out_Data : out Ada.Streams.Stream_Element_Array; |
| 113 |
Out_Last : out Ada.Streams.Stream_Element_Offset; |
| 114 |
Flush : in Flush_Mode); |
| 115 |
-- translate routine without additional headers. |
| 116 |
|
| 117 |
----------------- |
| 118 |
-- Check_Error -- |
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----------------- |
| 120 |
|
| 121 |
procedure Check_Error (Stream : in Z_Stream; Code : in Thin.Int) is |
| 122 |
use type Thin.Int; |
| 123 |
begin |
| 124 |
if Code /= Thin.Z_OK then |
| 125 |
Raise_Error |
| 126 |
(Return_Code_Enum'Image (Return_Code (Code)) |
| 127 |
& ": " & Last_Error_Message (Stream)); |
| 128 |
end if; |
| 129 |
end Check_Error; |
| 130 |
|
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----------- |
| 132 |
-- Close -- |
| 133 |
----------- |
| 134 |
|
| 135 |
procedure Close |
| 136 |
(Filter : in out Filter_Type; |
| 137 |
Ignore_Error : in Boolean := False) |
| 138 |
is |
| 139 |
Code : Thin.Int; |
| 140 |
begin |
| 141 |
if not Ignore_Error and then not Is_Open (Filter) then |
| 142 |
raise Status_Error; |
| 143 |
end if; |
| 144 |
|
| 145 |
Code := Flate (Filter.Compression).Done (To_Thin_Access (Filter.Strm)); |
| 146 |
|
| 147 |
if Ignore_Error or else Code = Thin.Z_OK then |
| 148 |
Free (Filter.Strm); |
| 149 |
else |
| 150 |
declare |
| 151 |
Error_Message : constant String |
| 152 |
:= Last_Error_Message (Filter.Strm.all); |
| 153 |
begin |
| 154 |
Free (Filter.Strm); |
| 155 |
Ada.Exceptions.Raise_Exception |
| 156 |
(ZLib_Error'Identity, |
| 157 |
Return_Code_Enum'Image (Return_Code (Code)) |
| 158 |
& ": " & Error_Message); |
| 159 |
end; |
| 160 |
end if; |
| 161 |
end Close; |
| 162 |
|
| 163 |
----------- |
| 164 |
-- CRC32 -- |
| 165 |
----------- |
| 166 |
|
| 167 |
function CRC32 |
| 168 |
(CRC : in Unsigned_32; |
| 169 |
Data : in Ada.Streams.Stream_Element_Array) |
| 170 |
return Unsigned_32 |
| 171 |
is |
| 172 |
use Thin; |
| 173 |
begin |
| 174 |
return Unsigned_32 (crc32 (ULong (CRC), |
| 175 |
Data'Address, |
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Data'Length)); |
| 177 |
end CRC32; |
| 178 |
|
| 179 |
procedure CRC32 |
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(CRC : in out Unsigned_32; |
| 181 |
Data : in Ada.Streams.Stream_Element_Array) is |
| 182 |
begin |
| 183 |
CRC := CRC32 (CRC, Data); |
| 184 |
end CRC32; |
| 185 |
|
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------------------ |
| 187 |
-- Deflate_Init -- |
| 188 |
------------------ |
| 189 |
|
| 190 |
procedure Deflate_Init |
| 191 |
(Filter : in out Filter_Type; |
| 192 |
Level : in Compression_Level := Default_Compression; |
| 193 |
Strategy : in Strategy_Type := Default_Strategy; |
| 194 |
Method : in Compression_Method := Deflated; |
| 195 |
Window_Bits : in Window_Bits_Type := Default_Window_Bits; |
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Memory_Level : in Memory_Level_Type := Default_Memory_Level; |
| 197 |
Header : in Header_Type := Default) |
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is |
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use type Thin.Int; |
| 200 |
Win_Bits : Thin.Int := Thin.Int (Window_Bits); |
| 201 |
begin |
| 202 |
if Is_Open (Filter) then |
| 203 |
raise Status_Error; |
| 204 |
end if; |
| 205 |
|
| 206 |
-- We allow ZLib to make header only in case of default header type. |
| 207 |
-- Otherwise we would either do header by ourselfs, or do not do |
| 208 |
-- header at all. |
| 209 |
|
| 210 |
if Header = None or else Header = GZip then |
| 211 |
Win_Bits := -Win_Bits; |
| 212 |
end if; |
| 213 |
|
| 214 |
-- For the GZip CRC calculation and make headers. |
| 215 |
|
| 216 |
if Header = GZip then |
| 217 |
Filter.CRC := 0; |
| 218 |
Filter.Offset := Simple_GZip_Header'First; |
| 219 |
else |
| 220 |
Filter.Offset := Simple_GZip_Header'Last + 1; |
| 221 |
end if; |
| 222 |
|
| 223 |
Filter.Strm := new Z_Stream; |
| 224 |
Filter.Compression := True; |
| 225 |
Filter.Stream_End := False; |
| 226 |
Filter.Header := Header; |
| 227 |
|
| 228 |
if Thin.Deflate_Init |
| 229 |
(To_Thin_Access (Filter.Strm), |
| 230 |
Level => Thin.Int (Level), |
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method => Thin.Int (Method), |
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windowBits => Win_Bits, |
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memLevel => Thin.Int (Memory_Level), |
| 234 |
strategy => Thin.Int (Strategy)) /= Thin.Z_OK |
| 235 |
then |
| 236 |
Raise_Error (Filter.Strm.all); |
| 237 |
end if; |
| 238 |
end Deflate_Init; |
| 239 |
|
| 240 |
----------- |
| 241 |
-- Flush -- |
| 242 |
----------- |
| 243 |
|
| 244 |
procedure Flush |
| 245 |
(Filter : in out Filter_Type; |
| 246 |
Out_Data : out Ada.Streams.Stream_Element_Array; |
| 247 |
Out_Last : out Ada.Streams.Stream_Element_Offset; |
| 248 |
Flush : in Flush_Mode) |
| 249 |
is |
| 250 |
No_Data : Stream_Element_Array := (1 .. 0 => 0); |
| 251 |
Last : Stream_Element_Offset; |
| 252 |
begin |
| 253 |
Translate (Filter, No_Data, Last, Out_Data, Out_Last, Flush); |
| 254 |
end Flush; |
| 255 |
|
| 256 |
----------------------- |
| 257 |
-- Generic_Translate -- |
| 258 |
----------------------- |
| 259 |
|
| 260 |
procedure Generic_Translate |
| 261 |
(Filter : in out ZLib.Filter_Type; |
| 262 |
In_Buffer_Size : in Integer := Default_Buffer_Size; |
| 263 |
Out_Buffer_Size : in Integer := Default_Buffer_Size) |
| 264 |
is |
| 265 |
In_Buffer : Stream_Element_Array |
| 266 |
(1 .. Stream_Element_Offset (In_Buffer_Size)); |
| 267 |
Out_Buffer : Stream_Element_Array |
| 268 |
(1 .. Stream_Element_Offset (Out_Buffer_Size)); |
| 269 |
Last : Stream_Element_Offset; |
| 270 |
In_Last : Stream_Element_Offset; |
| 271 |
In_First : Stream_Element_Offset; |
| 272 |
Out_Last : Stream_Element_Offset; |
| 273 |
begin |
| 274 |
Main : loop |
| 275 |
Data_In (In_Buffer, Last); |
| 276 |
|
| 277 |
In_First := In_Buffer'First; |
| 278 |
|
| 279 |
loop |
| 280 |
Translate |
| 281 |
(Filter => Filter, |
| 282 |
In_Data => In_Buffer (In_First .. Last), |
| 283 |
In_Last => In_Last, |
| 284 |
Out_Data => Out_Buffer, |
| 285 |
Out_Last => Out_Last, |
| 286 |
Flush => Flush_Finish (Last < In_Buffer'First)); |
| 287 |
|
| 288 |
if Out_Buffer'First <= Out_Last then |
| 289 |
Data_Out (Out_Buffer (Out_Buffer'First .. Out_Last)); |
| 290 |
end if; |
| 291 |
|
| 292 |
exit Main when Stream_End (Filter); |
| 293 |
|
| 294 |
-- The end of in buffer. |
| 295 |
|
| 296 |
exit when In_Last = Last; |
| 297 |
|
| 298 |
In_First := In_Last + 1; |
| 299 |
end loop; |
| 300 |
end loop Main; |
| 301 |
|
| 302 |
end Generic_Translate; |
| 303 |
|
| 304 |
------------------ |
| 305 |
-- Inflate_Init -- |
| 306 |
------------------ |
| 307 |
|
| 308 |
procedure Inflate_Init |
| 309 |
(Filter : in out Filter_Type; |
| 310 |
Window_Bits : in Window_Bits_Type := Default_Window_Bits; |
| 311 |
Header : in Header_Type := Default) |
| 312 |
is |
| 313 |
use type Thin.Int; |
| 314 |
Win_Bits : Thin.Int := Thin.Int (Window_Bits); |
| 315 |
|
| 316 |
procedure Check_Version; |
| 317 |
-- Check the latest header types compatibility. |
| 318 |
|
| 319 |
procedure Check_Version is |
| 320 |
begin |
| 321 |
if Version <= "1.1.4" then |
| 322 |
Raise_Error |
| 323 |
("Inflate header type " & Header_Type'Image (Header) |
| 324 |
& " incompatible with ZLib version " & Version); |
| 325 |
end if; |
| 326 |
end Check_Version; |
| 327 |
|
| 328 |
begin |
| 329 |
if Is_Open (Filter) then |
| 330 |
raise Status_Error; |
| 331 |
end if; |
| 332 |
|
| 333 |
case Header is |
| 334 |
when None => |
| 335 |
Check_Version; |
| 336 |
|
| 337 |
-- Inflate data without headers determined |
| 338 |
-- by negative Win_Bits. |
| 339 |
|
| 340 |
Win_Bits := -Win_Bits; |
| 341 |
when GZip => |
| 342 |
Check_Version; |
| 343 |
|
| 344 |
-- Inflate gzip data defined by flag 16. |
| 345 |
|
| 346 |
Win_Bits := Win_Bits + 16; |
| 347 |
when Auto => |
| 348 |
Check_Version; |
| 349 |
|
| 350 |
-- Inflate with automatic detection |
| 351 |
-- of gzip or native header defined by flag 32. |
| 352 |
|
| 353 |
Win_Bits := Win_Bits + 32; |
| 354 |
when Default => null; |
| 355 |
end case; |
| 356 |
|
| 357 |
Filter.Strm := new Z_Stream; |
| 358 |
Filter.Compression := False; |
| 359 |
Filter.Stream_End := False; |
| 360 |
Filter.Header := Header; |
| 361 |
|
| 362 |
if Thin.Inflate_Init |
| 363 |
(To_Thin_Access (Filter.Strm), Win_Bits) /= Thin.Z_OK |
| 364 |
then |
| 365 |
Raise_Error (Filter.Strm.all); |
| 366 |
end if; |
| 367 |
end Inflate_Init; |
| 368 |
|
| 369 |
------------- |
| 370 |
-- Is_Open -- |
| 371 |
------------- |
| 372 |
|
| 373 |
function Is_Open (Filter : in Filter_Type) return Boolean is |
| 374 |
begin |
| 375 |
return Filter.Strm /= null; |
| 376 |
end Is_Open; |
| 377 |
|
| 378 |
----------------- |
| 379 |
-- Raise_Error -- |
| 380 |
----------------- |
| 381 |
|
| 382 |
procedure Raise_Error (Message : in String) is |
| 383 |
begin |
| 384 |
Ada.Exceptions.Raise_Exception (ZLib_Error'Identity, Message); |
| 385 |
end Raise_Error; |
| 386 |
|
| 387 |
procedure Raise_Error (Stream : in Z_Stream) is |
| 388 |
begin |
| 389 |
Raise_Error (Last_Error_Message (Stream)); |
| 390 |
end Raise_Error; |
| 391 |
|
| 392 |
---------- |
| 393 |
-- Read -- |
| 394 |
---------- |
| 395 |
|
| 396 |
procedure Read |
| 397 |
(Filter : in out Filter_Type; |
| 398 |
Item : out Ada.Streams.Stream_Element_Array; |
| 399 |
Last : out Ada.Streams.Stream_Element_Offset; |
| 400 |
Flush : in Flush_Mode := No_Flush) |
| 401 |
is |
| 402 |
In_Last : Stream_Element_Offset; |
| 403 |
Item_First : Ada.Streams.Stream_Element_Offset := Item'First; |
| 404 |
V_Flush : Flush_Mode := Flush; |
| 405 |
|
| 406 |
begin |
| 407 |
pragma Assert (Rest_First in Buffer'First .. Buffer'Last + 1); |
| 408 |
pragma Assert (Rest_Last in Buffer'First - 1 .. Buffer'Last); |
| 409 |
|
| 410 |
loop |
| 411 |
if Rest_Last = Buffer'First - 1 then |
| 412 |
V_Flush := Finish; |
| 413 |
|
| 414 |
elsif Rest_First > Rest_Last then |
| 415 |
Read (Buffer, Rest_Last); |
| 416 |
Rest_First := Buffer'First; |
| 417 |
|
| 418 |
if Rest_Last < Buffer'First then |
| 419 |
V_Flush := Finish; |
| 420 |
end if; |
| 421 |
end if; |
| 422 |
|
| 423 |
Translate |
| 424 |
(Filter => Filter, |
| 425 |
In_Data => Buffer (Rest_First .. Rest_Last), |
| 426 |
In_Last => In_Last, |
| 427 |
Out_Data => Item (Item_First .. Item'Last), |
| 428 |
Out_Last => Last, |
| 429 |
Flush => V_Flush); |
| 430 |
|
| 431 |
Rest_First := In_Last + 1; |
| 432 |
|
| 433 |
exit when Stream_End (Filter) |
| 434 |
or else Last = Item'Last |
| 435 |
or else (Last >= Item'First and then Allow_Read_Some); |
| 436 |
|
| 437 |
Item_First := Last + 1; |
| 438 |
end loop; |
| 439 |
end Read; |
| 440 |
|
| 441 |
---------------- |
| 442 |
-- Stream_End -- |
| 443 |
---------------- |
| 444 |
|
| 445 |
function Stream_End (Filter : in Filter_Type) return Boolean is |
| 446 |
begin |
| 447 |
if Filter.Header = GZip and Filter.Compression then |
| 448 |
return Filter.Stream_End |
| 449 |
and then Filter.Offset = Footer_Array'Last + 1; |
| 450 |
else |
| 451 |
return Filter.Stream_End; |
| 452 |
end if; |
| 453 |
end Stream_End; |
| 454 |
|
| 455 |
-------------- |
| 456 |
-- Total_In -- |
| 457 |
-------------- |
| 458 |
|
| 459 |
function Total_In (Filter : in Filter_Type) return Count is |
| 460 |
begin |
| 461 |
return Count (Thin.Total_In (To_Thin_Access (Filter.Strm).all)); |
| 462 |
end Total_In; |
| 463 |
|
| 464 |
--------------- |
| 465 |
-- Total_Out -- |
| 466 |
--------------- |
| 467 |
|
| 468 |
function Total_Out (Filter : in Filter_Type) return Count is |
| 469 |
begin |
| 470 |
return Count (Thin.Total_Out (To_Thin_Access (Filter.Strm).all)); |
| 471 |
end Total_Out; |
| 472 |
|
| 473 |
--------------- |
| 474 |
-- Translate -- |
| 475 |
--------------- |
| 476 |
|
| 477 |
procedure Translate |
| 478 |
(Filter : in out Filter_Type; |
| 479 |
In_Data : in Ada.Streams.Stream_Element_Array; |
| 480 |
In_Last : out Ada.Streams.Stream_Element_Offset; |
| 481 |
Out_Data : out Ada.Streams.Stream_Element_Array; |
| 482 |
Out_Last : out Ada.Streams.Stream_Element_Offset; |
| 483 |
Flush : in Flush_Mode) is |
| 484 |
begin |
| 485 |
if Filter.Header = GZip and then Filter.Compression then |
| 486 |
Translate_GZip |
| 487 |
(Filter => Filter, |
| 488 |
In_Data => In_Data, |
| 489 |
In_Last => In_Last, |
| 490 |
Out_Data => Out_Data, |
| 491 |
Out_Last => Out_Last, |
| 492 |
Flush => Flush); |
| 493 |
else |
| 494 |
Translate_Auto |
| 495 |
(Filter => Filter, |
| 496 |
In_Data => In_Data, |
| 497 |
In_Last => In_Last, |
| 498 |
Out_Data => Out_Data, |
| 499 |
Out_Last => Out_Last, |
| 500 |
Flush => Flush); |
| 501 |
end if; |
| 502 |
end Translate; |
| 503 |
|
| 504 |
-------------------- |
| 505 |
-- Translate_Auto -- |
| 506 |
-------------------- |
| 507 |
|
| 508 |
procedure Translate_Auto |
| 509 |
(Filter : in out Filter_Type; |
| 510 |
In_Data : in Ada.Streams.Stream_Element_Array; |
| 511 |
In_Last : out Ada.Streams.Stream_Element_Offset; |
| 512 |
Out_Data : out Ada.Streams.Stream_Element_Array; |
| 513 |
Out_Last : out Ada.Streams.Stream_Element_Offset; |
| 514 |
Flush : in Flush_Mode) |
| 515 |
is |
| 516 |
use type Thin.Int; |
| 517 |
Code : Thin.Int; |
| 518 |
|
| 519 |
begin |
| 520 |
if not Is_Open (Filter) then |
| 521 |
raise Status_Error; |
| 522 |
end if; |
| 523 |
|
| 524 |
if Out_Data'Length = 0 and then In_Data'Length = 0 then |
| 525 |
raise Constraint_Error; |
| 526 |
end if; |
| 527 |
|
| 528 |
Set_Out (Filter.Strm.all, Out_Data'Address, Out_Data'Length); |
| 529 |
Set_In (Filter.Strm.all, In_Data'Address, In_Data'Length); |
| 530 |
|
| 531 |
Code := Flate (Filter.Compression).Step |
| 532 |
(To_Thin_Access (Filter.Strm), |
| 533 |
Thin.Int (Flush)); |
| 534 |
|
| 535 |
if Code = Thin.Z_STREAM_END then |
| 536 |
Filter.Stream_End := True; |
| 537 |
else |
| 538 |
Check_Error (Filter.Strm.all, Code); |
| 539 |
end if; |
| 540 |
|
| 541 |
In_Last := In_Data'Last |
| 542 |
- Stream_Element_Offset (Avail_In (Filter.Strm.all)); |
| 543 |
Out_Last := Out_Data'Last |
| 544 |
- Stream_Element_Offset (Avail_Out (Filter.Strm.all)); |
| 545 |
end Translate_Auto; |
| 546 |
|
| 547 |
-------------------- |
| 548 |
-- Translate_GZip -- |
| 549 |
-------------------- |
| 550 |
|
| 551 |
procedure Translate_GZip |
| 552 |
(Filter : in out Filter_Type; |
| 553 |
In_Data : in Ada.Streams.Stream_Element_Array; |
| 554 |
In_Last : out Ada.Streams.Stream_Element_Offset; |
| 555 |
Out_Data : out Ada.Streams.Stream_Element_Array; |
| 556 |
Out_Last : out Ada.Streams.Stream_Element_Offset; |
| 557 |
Flush : in Flush_Mode) |
| 558 |
is |
| 559 |
Out_First : Stream_Element_Offset; |
| 560 |
|
| 561 |
procedure Add_Data (Data : in Stream_Element_Array); |
| 562 |
-- Add data to stream from the Filter.Offset till necessary, |
| 563 |
-- used for add gzip headr/footer. |
| 564 |
|
| 565 |
procedure Put_32 |
| 566 |
(Item : in out Stream_Element_Array; |
| 567 |
Data : in Unsigned_32); |
| 568 |
pragma Inline (Put_32); |
| 569 |
|
| 570 |
-------------- |
| 571 |
-- Add_Data -- |
| 572 |
-------------- |
| 573 |
|
| 574 |
procedure Add_Data (Data : in Stream_Element_Array) is |
| 575 |
Data_First : Stream_Element_Offset renames Filter.Offset; |
| 576 |
Data_Last : Stream_Element_Offset; |
| 577 |
Data_Len : Stream_Element_Offset; -- -1 |
| 578 |
Out_Len : Stream_Element_Offset; -- -1 |
| 579 |
begin |
| 580 |
Out_First := Out_Last + 1; |
| 581 |
|
| 582 |
if Data_First > Data'Last then |
| 583 |
return; |
| 584 |
end if; |
| 585 |
|
| 586 |
Data_Len := Data'Last - Data_First; |
| 587 |
Out_Len := Out_Data'Last - Out_First; |
| 588 |
|
| 589 |
if Data_Len <= Out_Len then |
| 590 |
Out_Last := Out_First + Data_Len; |
| 591 |
Data_Last := Data'Last; |
| 592 |
else |
| 593 |
Out_Last := Out_Data'Last; |
| 594 |
Data_Last := Data_First + Out_Len; |
| 595 |
end if; |
| 596 |
|
| 597 |
Out_Data (Out_First .. Out_Last) := Data (Data_First .. Data_Last); |
| 598 |
|
| 599 |
Data_First := Data_Last + 1; |
| 600 |
Out_First := Out_Last + 1; |
| 601 |
end Add_Data; |
| 602 |
|
| 603 |
------------ |
| 604 |
-- Put_32 -- |
| 605 |
------------ |
| 606 |
|
| 607 |
procedure Put_32 |
| 608 |
(Item : in out Stream_Element_Array; |
| 609 |
Data : in Unsigned_32) |
| 610 |
is |
| 611 |
D : Unsigned_32 := Data; |
| 612 |
begin |
| 613 |
for J in Item'First .. Item'First + 3 loop |
| 614 |
Item (J) := Stream_Element (D and 16#FF#); |
| 615 |
D := Shift_Right (D, 8); |
| 616 |
end loop; |
| 617 |
end Put_32; |
| 618 |
|
| 619 |
begin |
| 620 |
Out_Last := Out_Data'First - 1; |
| 621 |
|
| 622 |
if not Filter.Stream_End then |
| 623 |
Add_Data (Simple_GZip_Header); |
| 624 |
|
| 625 |
Translate_Auto |
| 626 |
(Filter => Filter, |
| 627 |
In_Data => In_Data, |
| 628 |
In_Last => In_Last, |
| 629 |
Out_Data => Out_Data (Out_First .. Out_Data'Last), |
| 630 |
Out_Last => Out_Last, |
| 631 |
Flush => Flush); |
| 632 |
|
| 633 |
CRC32 (Filter.CRC, In_Data (In_Data'First .. In_Last)); |
| 634 |
end if; |
| 635 |
|
| 636 |
if Filter.Stream_End and then Out_Last <= Out_Data'Last then |
| 637 |
-- This detection method would work only when |
| 638 |
-- Simple_GZip_Header'Last > Footer_Array'Last |
| 639 |
|
| 640 |
if Filter.Offset = Simple_GZip_Header'Last + 1 then |
| 641 |
Filter.Offset := Footer_Array'First; |
| 642 |
end if; |
| 643 |
|
| 644 |
declare |
| 645 |
Footer : Footer_Array; |
| 646 |
begin |
| 647 |
Put_32 (Footer, Filter.CRC); |
| 648 |
Put_32 (Footer (Footer'First + 4 .. Footer'Last), |
| 649 |
Unsigned_32 (Total_In (Filter))); |
| 650 |
Add_Data (Footer); |
| 651 |
end; |
| 652 |
end if; |
| 653 |
end Translate_GZip; |
| 654 |
|
| 655 |
------------- |
| 656 |
-- Version -- |
| 657 |
------------- |
| 658 |
|
| 659 |
function Version return String is |
| 660 |
begin |
| 661 |
return Interfaces.C.Strings.Value (Thin.zlibVersion); |
| 662 |
end Version; |
| 663 |
|
| 664 |
----------- |
| 665 |
-- Write -- |
| 666 |
----------- |
| 667 |
|
| 668 |
procedure Write |
| 669 |
(Filter : in out Filter_Type; |
| 670 |
Item : in Ada.Streams.Stream_Element_Array; |
| 671 |
Flush : in Flush_Mode := No_Flush) |
| 672 |
is |
| 673 |
Buffer : Stream_Element_Array (1 .. Buffer_Size); |
| 674 |
In_Last : Stream_Element_Offset; |
| 675 |
Out_Last : Stream_Element_Offset; |
| 676 |
In_First : Stream_Element_Offset := Item'First; |
| 677 |
begin |
| 678 |
if Item'Length = 0 and Flush = No_Flush then |
| 679 |
return; |
| 680 |
end if; |
| 681 |
|
| 682 |
loop |
| 683 |
Translate |
| 684 |
(Filter => Filter, |
| 685 |
In_Data => Item (In_First .. Item'Last), |
| 686 |
In_Last => In_Last, |
| 687 |
Out_Data => Buffer, |
| 688 |
Out_Last => Out_Last, |
| 689 |
Flush => Flush); |
| 690 |
|
| 691 |
if Out_Last >= Buffer'First then |
| 692 |
Write (Buffer (1 .. Out_Last)); |
| 693 |
end if; |
| 694 |
|
| 695 |
exit when In_Last = Item'Last or Stream_End (Filter); |
| 696 |
|
| 697 |
In_First := In_Last + 1; |
| 698 |
end loop; |
| 699 |
end Write; |
| 700 |
|
| 701 |
end ZLib; |
