-- 
-- I/O System Dependencies Package for MV 10000, ROLM Ada Development
--   Environment, AOS Operating System
-- 
-- This visible section is derived from SYSDEP_SPEC.ADA by Stewart French, TI
-- Derivation by Richard Conn, TI
-- 
package SYSDEP is

-- 
-- Open the console for binary I/O, no echo
-- 
    procedure OPEN_CONSOLE;
    pragma INLINE (OPEN_CONSOLE);

-- 
-- Close the console, resetting parameters to their original condition
-- 
    procedure CLOSE_CONSOLE;
    pragma INLINE (CLOSE_CONSOLE);

-- 
-- Put a character to the terminal.  There should be no translation of the
--   characters.  There may be exceptions to this rule (like CTRL-S and
--   CTRL-Q for flow control), and these exceptions must be identified in
--   IS_VALID_CHARACTER below.
-- 
    procedure PUT (CHAR : CHARACTER);
    pragma INLINE (PUT);

-- 
-- Get a character from the terminal keyboard with no echo and no
--   translations.
-- 
    procedure GET (CHAR : out CHARACTER);
    pragma INLINE (GET);

-- 
-- Returns a boolean indicating whether the character is safe to use in the
--   environment.  Suspicious characters may be CTRL-S, CTRL-Q, CTRL-C, CTRL-Y.
-- 
    function IS_VALID_CHARACTER (CHAR : CHARACTER) return BOOLEAN;
    pragma INLINE (IS_VALID_CHARACTER);

end SYSDEP;




with TTY_IO,
     SYS_CALLS,
     FILE_DEFINITIONS,
     FILE_IO,
     BIT_OPS;
package body SYSDEP is

    BUFFER_BYTE_PTR     : INTEGER;
    BUFFER              : INTEGER;

    INVALID_CHARS_ARRAY : array (1 .. 8) of CHARACTER;

    TERMINAL            : FILE_DEFINITIONS.CHANNEL_NUMBER;
    TTY                 : TTY_IO.FILE_TYPE;

-- 
    procedure OPEN_CONSOLE is

        CONSOLE_CHARACTERISTICS : FILE_IO.DEVICE_CHARACTERISTICS;
        ERROR_CODE              : INTEGER;
        AC0, AC1, AC2           : INTEGER;
        NAME                    : SYS_CALLS.CALL_NAME;
        ERROR_ID                : SYS_CALLS.ERROR_CODE;

    begin

        TTY_IO.OPEN (TTY, TTY_IO.INOUT_FILE, "@console");

        -- turn off the keyboard interrupt capabilities

        AC0 := 0;
        AC1 := 0;
        AC2 := 0;
        NAME := SYS_CALLS.KIOFF;
        SYS_CALLS.LONG_SYS (NAME, AC0, AC1, AC2, ERROR_ID);

        FILE_IO.OPEN
           ("@console", TERMINAL, ERROR_CODE,
            FILE_DEFINITIONS.OPEN_FOR_INPUT_OUTPUT +
            FILE_DEFINITIONS.BINARY_IO + FILE_DEFINITIONS.VARIABLE_LENGTH);

        FILE_IO.GET_CHARACTERISTICS
           (TERMINAL, CONSOLE_CHARACTERISTICS, ERROR_CODE);
        CONSOLE_CHARACTERISTICS.ECHO := FILE_IO.NO_ECHO;
        CONSOLE_CHARACTERISTICS.CHARACTERISTICS
           (FILE_IO.NON_ANSI_STANDARD_DEVICE) := FALSE;
        FILE_IO.SET_CHARACTERISTICS
           (TERMINAL, CONSOLE_CHARACTERISTICS, ERROR_CODE);

        BUFFER_BYTE_PTR := INTEGER'VAL (BUFFER'ADDRESS);
        BUFFER_BYTE_PTR := BIT_OPS.LEFT_SHIFT_BY_1 (BUFFER_BYTE_PTR);

    end OPEN_CONSOLE;
--  pragma inline (OPEN_CONSOLE);

-- 
    procedure CLOSE_CONSOLE is

        ERROR_CODE : INTEGER;

    begin
        FILE_IO.CLOSE (TERMINAL, ERROR_CODE);
    end CLOSE_CONSOLE;
--  pragma inline (CLOSE_CONSOLE);


-- 
    procedure PUT (CHAR : CHARACTER) is

        DATA : STRING (1 .. 1);

    begin
        DATA (1) := CHAR;
        TTY_IO.PUT (TTY, DATA);
    end PUT;
--  pragma inline (PUT);

-- 
    procedure GET (CHAR : out CHARACTER) is

        BYTES_READ : INTEGER;
        ERROR_CODE : INTEGER;

    begin
        FILE_IO.READ
           (TERMINAL, ERROR_CODE, BYTES_READ, BUFFER_BYTE_PTR,
            FILE_DEFINITIONS.BINARY_IO, 1);
        BUFFER := BIT_OPS.LOGICAL_RIGHT_SHIFT (BUFFER, 24);
        CHAR := CHARACTER'VAL (BUFFER);

    end GET;
--  pragma inline (GET);


-- 
    function IS_VALID_CHARACTER (CHAR : CHARACTER) return BOOLEAN is

        VALID_FLAG : BOOLEAN;

    begin
        VALID_FLAG := TRUE;
        for I in 1 .. 8 loop
            if INVALID_CHARS_ARRAY (I) = CHAR then
                VALID_FLAG := FALSE;
            end if;
        end loop;
        return VALID_FLAG;
    end IS_VALID_CHARACTER;
--  pragma inline (IS_VALID_CHARACTER);

begin

    -- please refer to AOS/VS Programmer's Manual, Volume 1, System Concepts
    -- page 5-20 for a description of these character codes.

    INVALID_CHARS_ARRAY (4) := ASCII.DC3; -- CTRL-S
    INVALID_CHARS_ARRAY (5) := ASCII.DC1; -- CTRL-Q

end SYSDEP;