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    Length: 6364 (0x18dc)
    Types: TextFile
    Names: »B«

└─⟦afbc8121e⟧ Bits:30000532 8mm tape, Rational 1000, MC68020_OS2000 7_2_2
    └─⟦77aa8350c⟧ »DATA« 
        └─⟦f794ecd1d⟧ 
            └─⟦4c85d69e2⟧ 
                └─⟦this⟧ 

TextFile

--    The use of this system is subject to the software license terms and
--    conditions agreed upon between Rational and the Customer.
--
--                Copyright 1988 by Rational.
--
--                          RESTRICTED RIGHTS LEGEND
--
--    Use, duplication, or disclosure by the Government is subject to
--    restrictions as set forth in subdivision (b)(3)(ii) of the Rights in
--    Technical Data and Computer Software clause at 52.227-7013.
--
--
--                Rational
--                3320 Scott Boulevard
--                Santa Clara, California 95054-3197
--
--   PROPRIETARY AND CONFIDENTIAL INFORMATION OF RATIONAL;
--   USE OR COPYING WITHOUT EXPRESS WRITTEN AUTHORIZATION
--   IS STRICTLY PROHIBITED.  THIS MATERIAL IS PROTECTED AS
--   AN UNPUBLISHED WORK UNDER THE U.S. COPYRIGHT ACT OF
--   1976.  CREATED 1988.  ALL RIGHTS RESERVED.
--
--

with Primitive_Io;  -- For debugging only

with Io_Parameters;
pragma Elaborate (Io_Parameters);

separate (Common_Text_Io)

procedure Fill_Buffer (File     :        File_Type;
                       S        : in out Input_State;
                       B        : in out Buffering.Data_Buffer;
                       Undo_Eof :        Boolean := False) is

    Slide_Amount             : Integer;
    Count                    : Natural;
    Line_Terminator_Detected : Boolean;
    Line_Last_Data_Index     : Natural;
    Line_Terminator_Present  : Boolean;
    Empty_Buffer             : constant Boolean := Buffering.Is_Empty (B);

    Use_Block_Moves : Boolean renames Io_Parameters.Use_Block_Moves;

    -- procedure Pput (S : in String;
    --                 Absorb_Output : Boolean :=
    --                    Primitive_Io.Global_Absorb_Output)
    --     renames Primitive_Io.Put_Line;

begin
    -- Pput ("Cti.Fill_Buffer, Empty_Buffer = " & Boolean'Image (Empty_Buffer));

    case S.Eof_Encountered is

        when False =>
            if Buffering.Is_Full (B) then
                return;
            end if;

        when True =>
            -- Pput ("Cti.Fill_Buffer has Eof_Encountered on entry");
            return;  -- there are no characters to get

        when Simulated_False =>
            -- EOF has already happened, but we are pretending that is
            -- hasn't
            -- Pput ("Cti.Fill_Buffer has Simulated_False Eof on entry");
            if Undo_Eof then
                null;  -- Imagine that we get the EOF and then put it back.
            else
                -- Do Normal EOF processing
                S.Eof_Encountered := True;
                New_Page (S);
            end if;
            return;
    end case;

    -- Make all possible room in the buffer.
    Slide_Amount := B.Tail - 1;
    if Empty_Buffer then
        Buffering.Clear (B);
    else
        Buffering.Slide (B);
    end if;

    -- Adjust line start for amount of slide
    S.Line_Start := S.Line_Start - Slide_Amount;

    -- Pput ("Cti.Fill_Buffer buffer after sliding");
    -- Buffering.Display_Buffer (B);

    begin
        -- Pput ("Cti.Fill_Buffer calling Dio.Read");
        Dio.Read (File => File,
                  Item => B.Buffer (B.Head + 1 .. B.Max_Length),
                  Count => Count,
                  Line_Terminator_Detected => Line_Terminator_Detected,
                  Line_Last_Data_Index => Line_Last_Data_Index,
                  Line_Terminator_Present => Line_Terminator_Present,
                  Already_Locked => True);
    exception
        when End_Error =>
            -- Pput ("Cti.Fill_Buffer has End_Error after Dio.Read; Undo_Eof = " &
            --       Boolean'Image (Undo_Eof));
            if Undo_Eof or else not Empty_Buffer then
                S.Eof_Encountered := Simulated_False;
            else
                -- Do Normal EOF processing
                S.Eof_Encountered := True;
                New_Page (S);
            end if;
            return;
        when others =>
            -- Pput ("Cti.Fill_Buffer has some exception after Dio.Read");
            raise;
    end;

    -- Pput ("Cti.Fill_Buffer has" & Integer'Image (Count) &
    --       " bytes, Line_Terminator_Detected = " &
    --       Boolean'Image (Line_Terminator_Detected));
    -- Pput ("                    Line_Terminator_Present = " &
    --       Boolean'Image (Line_Terminator_Present) &
    --       ", line_last_data_index =" & Integer'Image (Line_Last_Data_Index));

    -- This version of Fill_Buffer will put a Line_Terminator at the
    -- end of every line.

    if Line_Terminator_Detected then
        Buffering.Bump (B, Count);

        -- We will insert Line_Terminators into the buffer where
        -- needed, but will take care to preserve the notion that
        -- a Page_Terminator is also a Line_Terminator.
        if not Line_Terminator_Present then
            if Buffering.Is_Empty (B) or else
               Buffering.Peek_At_Last (B) /= Page_Terminator then
                -- Pput ("Cti.Fill_Buffer adding Line_Terminator");
                Buffering.Stuff (B, Line_Terminator);
            end if;
        end if;
        S.Eob_Is_Eol := Empty_Buffer and Use_Block_Moves;

        -- Buffering.Display_Buffer (B);
    else
        -- If we didn't find a line terminator, then we assert that
        -- we have at least one character.
        if Count = 0 then
            raise Use_Error;
        end if;
        Buffering.Bump (B, Count);

        -- Buffering.Display_Buffer (B);

        -- for I in B.Tail .. B.Head loop
        --     Pput ("Have character " & Buffering.To_Character (B.Buffer (I)));
        -- end loop;

        S.Eob_Is_Eol := False;
    end if;

    -- Pput ("Cti.Fill_Buffer Eob_Is_Eol = " & Boolean'Image (S.Eob_Is_Eol));
    -- Pput ("                Line_Start =" & Integer'Image (S.Line_Start));

exception

    when Constraint_Error =>
        -- Pput ("Cti.Fill_Buffer has Constraint_Error");
        raise Iof.Input_Value_Error;

    when Numeric_Error =>
        -- Pput ("Cti.Fill_Buffer has Numeric_Error");
        raise Iof.Input_Value_Error;

    when Use_Error | Data_Error | Layout_Error | Status_Error =>
        -- Pput ("Cti.Fill_Buffer has Use_, Data_, Layout_, or Status_Error");
        raise;

    when others =>
        -- Pput
        --    ("Cti.Fill_Buffer:  Some exception raised, reflecting Device_Error");
        raise Device_Error;
end Fill_Buffer;