1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- I N T E R F A C E S . P A C K E D _ D E C I M A L -- 6-- -- 7-- B o d y -- 8-- (Version for IBM Mainframe Packed Decimal Format) -- 9-- -- 10-- Copyright (C) 1992-2009, Free Software Foundation, Inc. -- 11-- -- 12-- GNAT is free software; you can redistribute it and/or modify it under -- 13-- terms of the GNU General Public License as published by the Free Soft- -- 14-- ware Foundation; either version 3, or (at your option) any later ver- -- 15-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 16-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 17-- or FITNESS FOR A PARTICULAR PURPOSE. -- 18-- -- 19-- As a special exception under Section 7 of GPL version 3, you are granted -- 20-- additional permissions described in the GCC Runtime Library Exception, -- 21-- version 3.1, as published by the Free Software Foundation. -- 22-- -- 23-- You should have received a copy of the GNU General Public License and -- 24-- a copy of the GCC Runtime Library Exception along with this program; -- 25-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 26-- <http://www.gnu.org/licenses/>. -- 27-- -- 28-- GNAT was originally developed by the GNAT team at New York University. -- 29-- Extensive contributions were provided by Ada Core Technologies Inc. -- 30-- -- 31------------------------------------------------------------------------------ 32 33with System; use System; 34 35with Ada.Unchecked_Conversion; 36 37package body Interfaces.Packed_Decimal is 38 39 type Packed is array (Byte_Length) of Unsigned_8; 40 -- The type used internally to represent packed decimal 41 42 type Packed_Ptr is access Packed; 43 function To_Packed_Ptr is 44 new Ada.Unchecked_Conversion (Address, Packed_Ptr); 45 46 -- The following array is used to convert a value in the range 0-99 to 47 -- a packed decimal format with two hexadecimal nibbles. It is worth 48 -- using table look up in this direction because divides are expensive. 49 50 Packed_Byte : constant array (00 .. 99) of Unsigned_8 := 51 (16#00#, 16#01#, 16#02#, 16#03#, 16#04#, 52 16#05#, 16#06#, 16#07#, 16#08#, 16#09#, 53 16#10#, 16#11#, 16#12#, 16#13#, 16#14#, 54 16#15#, 16#16#, 16#17#, 16#18#, 16#19#, 55 16#20#, 16#21#, 16#22#, 16#23#, 16#24#, 56 16#25#, 16#26#, 16#27#, 16#28#, 16#29#, 57 16#30#, 16#31#, 16#32#, 16#33#, 16#34#, 58 16#35#, 16#36#, 16#37#, 16#38#, 16#39#, 59 16#40#, 16#41#, 16#42#, 16#43#, 16#44#, 60 16#45#, 16#46#, 16#47#, 16#48#, 16#49#, 61 16#50#, 16#51#, 16#52#, 16#53#, 16#54#, 62 16#55#, 16#56#, 16#57#, 16#58#, 16#59#, 63 16#60#, 16#61#, 16#62#, 16#63#, 16#64#, 64 16#65#, 16#66#, 16#67#, 16#68#, 16#69#, 65 16#70#, 16#71#, 16#72#, 16#73#, 16#74#, 66 16#75#, 16#76#, 16#77#, 16#78#, 16#79#, 67 16#80#, 16#81#, 16#82#, 16#83#, 16#84#, 68 16#85#, 16#86#, 16#87#, 16#88#, 16#89#, 69 16#90#, 16#91#, 16#92#, 16#93#, 16#94#, 70 16#95#, 16#96#, 16#97#, 16#98#, 16#99#); 71 72 --------------------- 73 -- Int32_To_Packed -- 74 --------------------- 75 76 procedure Int32_To_Packed (V : Integer_32; P : System.Address; D : D32) is 77 PP : constant Packed_Ptr := To_Packed_Ptr (P); 78 Empty_Nibble : constant Boolean := ((D rem 2) = 0); 79 B : constant Byte_Length := (D / 2) + 1; 80 VV : Integer_32 := V; 81 82 begin 83 -- Deal with sign byte first 84 85 if VV >= 0 then 86 PP (B) := Unsigned_8 (VV rem 10) * 16 + 16#C#; 87 VV := VV / 10; 88 89 else 90 VV := -VV; 91 PP (B) := Unsigned_8 (VV rem 10) * 16 + 16#D#; 92 end if; 93 94 for J in reverse B - 1 .. 2 loop 95 if VV = 0 then 96 for K in 1 .. J loop 97 PP (K) := 16#00#; 98 end loop; 99 100 return; 101 102 else 103 PP (J) := Packed_Byte (Integer (VV rem 100)); 104 VV := VV / 100; 105 end if; 106 end loop; 107 108 -- Deal with leading byte 109 110 if Empty_Nibble then 111 if VV > 9 then 112 raise Constraint_Error; 113 else 114 PP (1) := Unsigned_8 (VV); 115 end if; 116 117 else 118 if VV > 99 then 119 raise Constraint_Error; 120 else 121 PP (1) := Packed_Byte (Integer (VV)); 122 end if; 123 end if; 124 125 end Int32_To_Packed; 126 127 --------------------- 128 -- Int64_To_Packed -- 129 --------------------- 130 131 procedure Int64_To_Packed (V : Integer_64; P : System.Address; D : D64) is 132 PP : constant Packed_Ptr := To_Packed_Ptr (P); 133 Empty_Nibble : constant Boolean := ((D rem 2) = 0); 134 B : constant Byte_Length := (D / 2) + 1; 135 VV : Integer_64 := V; 136 137 begin 138 -- Deal with sign byte first 139 140 if VV >= 0 then 141 PP (B) := Unsigned_8 (VV rem 10) * 16 + 16#C#; 142 VV := VV / 10; 143 144 else 145 VV := -VV; 146 PP (B) := Unsigned_8 (VV rem 10) * 16 + 16#D#; 147 end if; 148 149 for J in reverse B - 1 .. 2 loop 150 if VV = 0 then 151 for K in 1 .. J loop 152 PP (K) := 16#00#; 153 end loop; 154 155 return; 156 157 else 158 PP (J) := Packed_Byte (Integer (VV rem 100)); 159 VV := VV / 100; 160 end if; 161 end loop; 162 163 -- Deal with leading byte 164 165 if Empty_Nibble then 166 if VV > 9 then 167 raise Constraint_Error; 168 else 169 PP (1) := Unsigned_8 (VV); 170 end if; 171 172 else 173 if VV > 99 then 174 raise Constraint_Error; 175 else 176 PP (1) := Packed_Byte (Integer (VV)); 177 end if; 178 end if; 179 180 end Int64_To_Packed; 181 182 --------------------- 183 -- Packed_To_Int32 -- 184 --------------------- 185 186 function Packed_To_Int32 (P : System.Address; D : D32) return Integer_32 is 187 PP : constant Packed_Ptr := To_Packed_Ptr (P); 188 Empty_Nibble : constant Boolean := ((D mod 2) = 0); 189 B : constant Byte_Length := (D / 2) + 1; 190 V : Integer_32; 191 Dig : Unsigned_8; 192 Sign : Unsigned_8; 193 J : Positive; 194 195 begin 196 -- Cases where there is an unused (zero) nibble in the first byte. 197 -- Deal with the single digit nibble at the right of this byte 198 199 if Empty_Nibble then 200 V := Integer_32 (PP (1)); 201 J := 2; 202 203 if V > 9 then 204 raise Constraint_Error; 205 end if; 206 207 -- Cases where all nibbles are used 208 209 else 210 V := 0; 211 J := 1; 212 end if; 213 214 -- Loop to process bytes containing two digit nibbles 215 216 while J < B loop 217 Dig := Shift_Right (PP (J), 4); 218 219 if Dig > 9 then 220 raise Constraint_Error; 221 else 222 V := V * 10 + Integer_32 (Dig); 223 end if; 224 225 Dig := PP (J) and 16#0F#; 226 227 if Dig > 9 then 228 raise Constraint_Error; 229 else 230 V := V * 10 + Integer_32 (Dig); 231 end if; 232 233 J := J + 1; 234 end loop; 235 236 -- Deal with digit nibble in sign byte 237 238 Dig := Shift_Right (PP (J), 4); 239 240 if Dig > 9 then 241 raise Constraint_Error; 242 else 243 V := V * 10 + Integer_32 (Dig); 244 end if; 245 246 Sign := PP (J) and 16#0F#; 247 248 -- Process sign nibble (deal with most common cases first) 249 250 if Sign = 16#C# then 251 return V; 252 253 elsif Sign = 16#D# then 254 return -V; 255 256 elsif Sign = 16#B# then 257 return -V; 258 259 elsif Sign >= 16#A# then 260 return V; 261 262 else 263 raise Constraint_Error; 264 end if; 265 end Packed_To_Int32; 266 267 --------------------- 268 -- Packed_To_Int64 -- 269 --------------------- 270 271 function Packed_To_Int64 (P : System.Address; D : D64) return Integer_64 is 272 PP : constant Packed_Ptr := To_Packed_Ptr (P); 273 Empty_Nibble : constant Boolean := ((D mod 2) = 0); 274 B : constant Byte_Length := (D / 2) + 1; 275 V : Integer_64; 276 Dig : Unsigned_8; 277 Sign : Unsigned_8; 278 J : Positive; 279 280 begin 281 -- Cases where there is an unused (zero) nibble in the first byte. 282 -- Deal with the single digit nibble at the right of this byte 283 284 if Empty_Nibble then 285 V := Integer_64 (PP (1)); 286 J := 2; 287 288 if V > 9 then 289 raise Constraint_Error; 290 end if; 291 292 -- Cases where all nibbles are used 293 294 else 295 J := 1; 296 V := 0; 297 end if; 298 299 -- Loop to process bytes containing two digit nibbles 300 301 while J < B loop 302 Dig := Shift_Right (PP (J), 4); 303 304 if Dig > 9 then 305 raise Constraint_Error; 306 else 307 V := V * 10 + Integer_64 (Dig); 308 end if; 309 310 Dig := PP (J) and 16#0F#; 311 312 if Dig > 9 then 313 raise Constraint_Error; 314 else 315 V := V * 10 + Integer_64 (Dig); 316 end if; 317 318 J := J + 1; 319 end loop; 320 321 -- Deal with digit nibble in sign byte 322 323 Dig := Shift_Right (PP (J), 4); 324 325 if Dig > 9 then 326 raise Constraint_Error; 327 else 328 V := V * 10 + Integer_64 (Dig); 329 end if; 330 331 Sign := PP (J) and 16#0F#; 332 333 -- Process sign nibble (deal with most common cases first) 334 335 if Sign = 16#C# then 336 return V; 337 338 elsif Sign = 16#D# then 339 return -V; 340 341 elsif Sign = 16#B# then 342 return -V; 343 344 elsif Sign >= 16#A# then 345 return V; 346 347 else 348 raise Constraint_Error; 349 end if; 350 end Packed_To_Int64; 351 352end Interfaces.Packed_Decimal; 353