+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNAT RUNTIME COMPONENTS --
--- --
--- S Y S T E M . I M G _ D E C --
--- --
--- B o d y --
--- --
--- $Revision: 1.1.16.1 $
--- --
--- Copyright (C) 1992-2001 Free Software Foundation, Inc. --
--- --
--- GNAT is free software; you can redistribute it and/or modify it under --
--- terms of the GNU General Public License as published by the Free Soft- --
--- ware Foundation; either version 2, or (at your option) any later ver- --
--- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
--- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
--- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
--- for more details. You should have received a copy of the GNU General --
--- Public License distributed with GNAT; see file COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
--- --
--- As a special exception, if other files instantiate generics from this --
--- unit, or you link this unit with other files to produce an executable, --
--- this unit does not by itself cause the resulting executable to be --
--- covered by the GNU General Public License. This exception does not --
--- however invalidate any other reasons why the executable file might be --
--- covered by the GNU Public License. --
--- --
--- GNAT was originally developed by the GNAT team at New York University. --
--- Extensive contributions were provided by Ada Core Technologies Inc. --
--- --
-------------------------------------------------------------------------------
-
-with System.Img_Int; use System.Img_Int;
-
-package body System.Img_Dec is
-
- -------------------
- -- Image_Decimal --
- -------------------
-
- function Image_Decimal
- (V : Integer;
- Scale : Integer)
- return String
- is
- P : Natural := 0;
- S : String (1 .. 64);
-
- begin
- Set_Image_Decimal (V, S, P, Scale, 1, Integer'Max (1, Scale), 0);
-
- -- Mess around to make sure we have the objectionable space at the
- -- start for positive numbers in accordance with the annoying rules!
-
- if S (1) /= ' ' and then S (1) /= '-' then
- S (2 .. P + 1) := S (1 .. P);
- S (1) := ' ';
- return S (1 .. P + 1);
- else
- return S (1 .. P);
- end if;
- end Image_Decimal;
-
- ------------------------
- -- Set_Decimal_Digits --
- ------------------------
-
- procedure Set_Decimal_Digits
- (Digs : in out String;
- NDigs : Natural;
- S : out String;
- P : in out Natural;
- Scale : Integer;
- Fore : Natural;
- Aft : Natural;
- Exp : Natural)
- is
- Minus : constant Boolean := (Digs (1) = '-');
- -- Set True if input is negative
-
- Zero : Boolean := (Digs (2) = '0');
- -- Set True if input is exactly zero (only case when a leading zero
- -- is permitted in the input string given to this procedure). This
- -- flag can get set later if rounding causes the value to become zero.
-
- FD : Natural := 2;
- -- First digit position of digits remaining to be processed
-
- LD : Natural := NDigs;
- -- Last digit position of digits remaining to be processed
-
- ND : Natural := NDigs - 1;
- -- Number of digits remaining to be processed (LD - FD + 1)
-
- Digits_Before_Point : Integer := ND - Scale;
- -- Number of digits before decimal point in the input value. This
- -- value can be negative if the input value is less than 0.1, so
- -- it is an indication of the current exponent. Digits_Before_Point
- -- is adjusted if the rounding step generates an extra digit.
-
- Digits_After_Point : constant Natural := Integer'Max (1, Aft);
- -- Digit positions after decimal point in result string
-
- Expon : Integer;
- -- Integer value of exponent
-
- procedure Round (N : Natural);
- -- Round the number in Digs. N is the position of the last digit to be
- -- retained in the rounded position (rounding is based on Digs (N + 1)
- -- FD, LD, ND are reset as necessary if required. Note that if the
- -- result value rounds up (e.g. 9.99 => 10.0), an extra digit can be
- -- placed in the sign position as a result of the rounding, this is
- -- the case in which FD is adjusted.
-
- procedure Set (C : Character);
- pragma Inline (Set);
- -- Sets character C in output buffer
-
- procedure Set_Blanks_And_Sign (N : Integer);
- -- Sets leading blanks and minus sign if needed. N is the number of
- -- positions to be filled (a minus sign is output even if N is zero
- -- or negative, For a positive value, if N is non-positive, then
- -- a leading blank is filled.
-
- procedure Set_Digits (S, E : Natural);
- pragma Inline (Set_Digits);
- -- Set digits S through E from Digs, no effect if S > E
-
- procedure Set_Zeroes (N : Integer);
- pragma Inline (Set_Zeroes);
- -- Set N zeroes, no effect if N is negative
-
- procedure Round (N : Natural) is
- D : Character;
-
- begin
- -- Nothing to do if rounding at or past last digit
-
- if N >= LD then
- return;
-
- -- Cases of rounding before the initial digit
-
- elsif N < FD then
-
- -- The result is zero, unless we are rounding just before
- -- the first digit, and the first digit is five or more.
-
- if N = 1 and then Digs (2) >= '5' then
- Digs (1) := '1';
- else
- Digs (1) := '0';
- Zero := True;
- end if;
-
- Digits_Before_Point := Digits_Before_Point + 1;
- FD := 1;
- LD := 1;
- ND := 1;
-
- -- Normal case of rounding an existing digit
-
- else
- LD := N;
- ND := LD - 1;
-
- if Digs (N + 1) >= '5' then
- for J in reverse 2 .. N loop
- D := Character'Succ (Digs (J));
-
- if D <= '9' then
- Digs (J) := D;
- return;
- else
- Digs (J) := '0';
- end if;
- end loop;
-
- -- Here the rounding overflows into the sign position. That's
- -- OK, because we already captured the value of the sign and
- -- we are in any case destroying the value in the Digs buffer
-
- Digs (1) := '1';
- FD := 1;
- ND := ND + 1;
- Digits_Before_Point := Digits_Before_Point + 1;
- end if;
- end if;
- end Round;
-
- procedure Set (C : Character) is
- begin
- P := P + 1;
- S (P) := C;
- end Set;
-
- procedure Set_Blanks_And_Sign (N : Integer) is
- W : Integer := N;
-
- begin
- if Minus then
- W := W - 1;
-
- for J in 1 .. W loop
- Set (' ');
- end loop;
-
- Set ('-');
-
- else
- for J in 1 .. W loop
- Set (' ');
- end loop;
- end if;
- end Set_Blanks_And_Sign;
-
- procedure Set_Digits (S, E : Natural) is
- begin
- for J in S .. E loop
- Set (Digs (J));
- end loop;
- end Set_Digits;
-
- procedure Set_Zeroes (N : Integer) is
- begin
- for J in 1 .. N loop
- Set ('0');
- end loop;
- end Set_Zeroes;
-
- -- Start of processing for Set_Decimal_Digits
-
- begin
- -- Case of exponent given
-
- if Exp > 0 then
- Set_Blanks_And_Sign (Fore - 1);
- Round (Aft + 2);
- Set (Digs (FD));
- FD := FD + 1;
- ND := ND - 1;
- Set ('.');
-
- if ND >= Digits_After_Point then
- Set_Digits (FD, FD + Digits_After_Point - 1);
-
- else
- Set_Digits (FD, LD);
- Set_Zeroes (Digits_After_Point - ND);
- end if;
-
- -- Calculate exponent. The number of digits before the decimal point
- -- in the input is Digits_Before_Point, and the number of digits
- -- before the decimal point in the output is 1, so we can get the
- -- exponent as the difference between these two values. The one
- -- exception is for the value zero, which by convention has an
- -- exponent of +0.
-
- if Zero then
- Expon := 0;
- else
- Expon := Digits_Before_Point - 1;
- end if;
-
- Set ('E');
- ND := 0;
-
- if Expon >= 0 then
- Set ('+');
- Set_Image_Integer (Expon, Digs, ND);
- else
- Set ('-');
- Set_Image_Integer (-Expon, Digs, ND);
- end if;
-
- Set_Zeroes (Exp - ND - 1);
- Set_Digits (1, ND);
- return;
-
- -- Case of no exponent given. To make these cases clear, we use
- -- examples. For all the examples, we assume Fore = 2, Aft = 3.
- -- A P in the example input string is an implied zero position,
- -- not included in the input string.
-
- else
- -- Round at correct position
- -- Input: 4PP => unchanged
- -- Input: 400.03 => unchanged
- -- Input 3.4567 => 3.457
- -- Input: 9.9999 => 10.000
- -- Input: 0.PPP5 => 0.001
- -- Input: 0.PPP4 => 0
- -- Input: 0.00003 => 0
-
- Round (LD - (Scale - Digits_After_Point));
-
- -- No digits before point in input
- -- Input: .123 Output: 0.123
- -- Input: .PP3 Output: 0.003
-
- if Digits_Before_Point <= 0 then
- Set_Blanks_And_Sign (Fore - 1);
- Set ('0');
- Set ('.');
-
- Set_Zeroes (Digits_After_Point - ND);
- Set_Digits (FD, LD);
-
- -- At least one digit before point in input
-
- else
- Set_Blanks_And_Sign (Fore - Digits_Before_Point);
-
- -- Less digits in input than are needed before point
- -- Input: 1PP Output: 100.000
-
- if ND < Digits_Before_Point then
- Set_Digits (FD, LD);
- Set_Zeroes (Digits_Before_Point - ND);
- Set ('.');
- Set_Zeroes (Digits_After_Point);
-
- -- Input has full amount of digits before decimal point
-
- else
- Set_Digits (FD, FD + Digits_Before_Point - 1);
- Set ('.');
- Set_Digits (FD + Digits_Before_Point, LD);
- Set_Zeroes (Digits_After_Point - (ND - Digits_Before_Point));
- end if;
- end if;
- end if;
-
- end Set_Decimal_Digits;
-
- -----------------------
- -- Set_Image_Decimal --
- -----------------------
-
- procedure Set_Image_Decimal
- (V : Integer;
- S : out String;
- P : in out Natural;
- Scale : Integer;
- Fore : Natural;
- Aft : Natural;
- Exp : Natural)
- is
- Digs : String := Image_Integer (V);
- -- Sign and digits of decimal value
-
- begin
- Set_Decimal_Digits (Digs, Digs'Length, S, P, Scale, Fore, Aft, Exp);
- end Set_Image_Decimal;
-
-end System.Img_Dec;
projects / msp430-gcc.git / blobdiff