1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 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 | with Zlib.Streams.Extra; with Ada.Unchecked_Deallocation; with Text_Io; package body Agpl.Streams.Deflate is -- Helper always ready function, will return Natural'Last: function Always_available ( This : access Ada.Streams.Root_stream_type'Class) return Natural is pragma Unreferenced (This); begin return Natural'Last; end Always_available; -- Helper never available, will return zero: function Never_Available ( This : access Ada.Streams.Root_stream_type'Class) return Natural is pragma Unreferenced (This); begin return 0; end Never_Available; ------------------------------------------------------------------------ -- Create -- ------------------------------------------------------------------------ -- The percent free says when Ready_for_writing will return true, according -- to the internal buffer filling. procedure Create ( Stream : out Stream_type; From : access Ada.Streams.Root_stream_type'Class; Avail_read : in Available_function; Avail_write : in Available_function; Buffer : in Positive := 4096; Percent_free : in Natural := 20) is begin Stream.Back := Agpl.Streams.Stream_access (From); Stream.Avail_read := Avail_read; Stream.Avail_write := Avail_write; Stream.Buffer_size := Buffer; Stream.Percent_free := Percent_free; Stream.Min_Free := Stream.Buffer_size * Stream.Percent_free / 100; Stream.Buf_in := new Circular.Stream_type (Stream_Element_Offset (Buffer)); Stream.Buf_out := new Circular.Stream_type (Stream_Element_Offset (Buffer)); Zlib.Streams.Create ( Stream.Zin, Zlib.Streams.Out_Stream, Zlib.Streams.Stream_Access (Stream.Buf_in), Back_compressed => false); Zlib.Streams.Create ( Stream.Zout, Zlib.Streams.Out_Stream, Zlib.Streams.Stream_Access (Stream.Buf_out), Back_compressed => true); end Create; ------------------------------------------------------------------------ -- Read -- ------------------------------------------------------------------------ procedure Read ( Stream : in out Stream_type; Item : out Ada.Streams.Stream_Element_Array; Last : out Ada.Streams.Stream_Element_Offset) is begin if Circular.Available_Read (Stream.Buf_In.all) = Natural'(0) or else Circular.Available_Read (Stream.Buf_In.all) < Natural'(Item'Length) then Attempt_read (Stream); end if; Circular.Read (Stream.Buf_in.all, Item, Last); Stream.Uncompressed_Read := Stream.Uncompressed_Read + Integer (Last - Item'First + 1); Stream.Gained_Read := Stream.Gained_Read + Integer (Last - Item'First + 1); end Read; ------------------------------------------------------------------------ -- Write -- ------------------------------------------------------------------------ procedure Write( Stream : in out Stream_type; Item : in Ada.Streams.Stream_Element_Array) is Avail : Ada.Streams.Stream_element_offset; begin if Stream.Unflushed_Zout >= Stream.Buffer_Size - Stream.Min_Free then --text_io.put_line ("Flushing because unflusehd is" & Stream.Unflushed_Zout'Img); Hard_Flush (Stream); --text_io.put_line ("Unflusehd is" & Stream.Unflushed_Zout'Img); --text_io.put_line ("Circular out avail read is" & -- Integer'Image (Circular.Available_Read (Stream.Buf_Out.all))); end if; if not Ready_For_Writing (Stream) then raise Write_Buffer_Is_Full; end if; -- Text_Io.Put_Line ("Deflate.Write:" & Integer'Image (Item'Length)); -- Write as much as possible, keep remaining in buffer: if Circular.Available_write (Stream.Buf_out.all) > Stream.Min_Free then Avail := Ada.Streams.Stream_Element_Offset'Min ( Circular.Available_Write (Stream.Buf_Out.all) - Stream_Element_Offset (Stream.Min_Free), Item'Length); Zlib.Streams.Write (Stream.Zout, Item (Item'First .. Item'First + Avail - 1)); Stream.Gained_Written := Stream.Gained_Written + Natural (Avail); Stream.Uncompressed_Written := Stream.Uncompressed_Written + Natural (Avail); Stream.UnFlushed_ZOut := Stream.Unflushed_Zout + Natural (Avail); else Avail := 0; end if; if Avail /= Item'Length then Stream.Pending_Write := new Ada.Streams.Stream_element_array'( Item (Item'First + Avail .. Item'Last)); Stream.Pending_Write_Pos := Stream.Pending_Write'First; end if; Attempt_Write (Stream); end Write; ------------------------------------------------------------------------ -- Available_read -- ------------------------------------------------------------------------ -- Says how many data is ready to be read function Available_Read (This : in Stream_Type) return Natural is begin return Circular.Available_Read (This.Buf_In.all); end Available_Read; ------------------------------------------------------------------------ -- Ready_for_writing -- ------------------------------------------------------------------------ function Ready_for_Writing (This : in Stream_type) return Boolean is begin return This.Pending_Write = null and then This.Unflushed_Zout < This.Buffer_Size - This.Min_Free and then Circular.Available_Write (This.Buf_Out.all) > This.Min_Free; end Ready_For_Writing; ------------------------------------------------------------------------ -- Finalize -- ------------------------------------------------------------------------ procedure Finalize (This : in out Stream_Type) is procedure Free is new Unchecked_Deallocation (Circular.Stream_Type, Circular.Stream_Access); begin -- Free pendings: Free (This.Pending_Write); -- Close Sockets: begin Zlib.Streams.Extra.Close_Abort (This.Zout); exception when others => raise; end; begin Zlib.Streams.Extra.Close_Abort (This.Zin); exception when others => raise; end; Free (This.Buf_In); Free (This.Buf_Out); end Finalize; ------------------------------------------------------------------------ -- Finalize -- ------------------------------------------------------------------------ procedure Finalize (This : in out Stream_finalizer) is begin Finalize (This.Parent.all); end Finalize; ------------------------------------------------------------------------ -- Close -- ------------------------------------------------------------------------ -- Will fail if there is data pending to be flushed procedure Close (Stream : in out Stream_Type) is begin if Stream.UnFlushed_ZOut > 0 or else Stream.Pending_Write /= null or else Circular.Available_Read (Stream.Buf_Out.all) /= Natural'(0) then raise Buffer_Not_Empty; end if; Finalize (Stream); end Close; ------------------------------------------------------------------------ -- Close_With_Abort -- ------------------------------------------------------------------------ -- Will always succeed, data pending will not be sent. procedure Close_With_Abort (Stream : in out Stream_Type) is begin Finalize (Stream); end Close_With_Abort; ------------------------------------------------------------------------ -- Soft_flush -- ------------------------------------------------------------------------ -- Do not flushes the Z streams, but the internal buffers to the -- back stream. procedure Soft_flush (Stream : in out Stream_type) is Avail : Ada.Streams.Stream_Element_Offset; begin -- Reading Attempt_Read (Stream); -- Writting Attempt_Write (Stream); if Stream.Pending_Write /= null and then Circular.Available_Write (Stream.Buf_Out.all) > Stream.Min_Free then Avail := Ada.Streams.Stream_Element_Offset'Min ( Stream.Pending_Write'Last - Stream.Pending_Write_Pos + 1, Circular.Available_Write (Stream.Buf_Out.all) - Stream_Element_Offset (Stream.Min_Free)); Zlib.Streams.Write (Stream.Zout, Stream.Pending_Write (Stream.Pending_Write_Pos .. Stream.Pending_Write_Pos + Avail - 1)); Stream.UnFlushed_ZOut := Stream.Unflushed_Zout + Natural (Avail); Stream.Pending_Write_Pos := Stream.Pending_Write_Pos + Avail; if Stream.Pending_Write_Pos > Stream.Pending_Write'Last then Free (Stream.Pending_Write); end if; -- Again Attempt_Write (Stream); end if; end Soft_Flush; ------------------------------------------------------------------------ -- Hard_flush -- ------------------------------------------------------------------------ -- Flushes all buffers, including the Z streams (reduces compression ratio) procedure Hard_Flush (Stream : in out Stream_type) is begin Soft_Flush (Stream); Zlib.Streams.Flush (Stream.Zout); Stream.UnFlushed_ZOut := 0; Attempt_Write (Stream); -- Previous can cause new data to be buffered. end Hard_Flush; ------------------------------------------------------------------------ -- Everything_Written -- ------------------------------------------------------------------------ -- True if no data is pending to be flushed/written in any internal buffer. -- Force this with Hard_Flush function Everything_Written (This : in Stream_Type) return Boolean is begin return This.UnFlushed_ZOut = 0 and then This.Pending_Write = null and then Circular.Available_Read (This.Buf_Out.all) = Natural'(0); end Everything_Written; ------------------------------------------------------------------------ -- Get_Write_Ratio -- ------------------------------------------------------------------------ -- Gives the compression ratio -- Gained / Written function Get_Write_Ratio (This : in Stream_Type) return Float is begin if This.Uncompressed_Written = 0 then return 0.0; else return Float (This.Gained_Written) / Float (This.Uncompressed_Written); end if; end Get_Write_Ratio; ------------------------------------------------------------------------ -- Get_Read_Ratio -- ------------------------------------------------------------------------ -- Gives the compression ratio -- Gained / Read function Get_Read_Ratio (This : in Stream_Type) return Float is begin if This.Uncompressed_Read = 0 then return 0.0; else return Float (This.Gained_Read) / Float (This.Uncompressed_Read); end if; end Get_Read_Ratio; ------------------------------------------------------------------------ -- Attempt_read -- ------------------------------------------------------------------------ -- Read as many data as possible restricted by availabilities. procedure Attempt_Read (Stream : in out Stream_type) is begin if Circular.Available_Write (Stream.Buf_In.all) > Stream.Min_Free then declare Avail : constant Stream_Element_Offset := Stream_Element_Offset'Min ( Circular.Available_Write (Stream.Buf_In.all) - Stream_Element_Offset (Stream.Min_free), Stream_Element_Offset (Stream.Avail_Read (Stream.Back))); Buf : Ada.Streams.Stream_Element_Array (1 .. Avail); Last : Ada.Streams.Stream_Element_Offset; begin if Buf'Length > 0 then --Text_Io.Put_Line ("Pushing data into zreader:" & Integer'Image (Buf'Length)); Ada.Streams.Read (Stream.Back.all, Buf, Last); if Last >= Buf'First then begin Zlib.Streams.Write (Stream.Zin, Buf (Buf'First .. Last)); exception when Constraint_Error => raise Read_Buffer_Is_Full; end; Stream.Gained_Read := Stream.Gained_Read - Natural (Last - Buf'First + 1); -- We decrease since when uncompressed the size will be greater end if; end if; end; end if; end Attempt_Read; ------------------------------------------------------------------------ -- Attempt_write -- ------------------------------------------------------------------------ -- Write as many data as possible restricted by availabilities. procedure Attempt_Write (Stream : in out Stream_type) is Avail : constant Stream_Element_Offset := Stream_Element_Offset'Min ( Circular.Available_Read (Stream.Buf_Out.all), Stream_Element_Offset (Stream.Avail_Write (Stream.Back))); Buf : Stream_Element_Array (1 .. Avail); Last : Stream_Element_Offset; begin if Avail > 0 then Circular.Read (Stream.Buf_Out.all, Buf, Last); if Last >= Buf'First then Ada.Streams.Write (Stream.Back.all, Buf (Buf'First .. Last)); Stream.Gained_Written := Stream.Gained_Written - Natural (Last - Buf'First + 1); end if; end if; end Attempt_Write; end Agpl.Streams.Deflate; |