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/*
** File: init.c
**
** (C)opyright 1987-1992 InfoTaskforce.
*/
#include "infocom.h"
Void
init ()
{
extern word resident_blocks ;
extern word save_blocks ;
extern header data_head ;
extern boolean pre_load ;
extern boolean stop ;
extern std_object_ptr std_obj_list ;
extern plus_object_ptr plus_obj_list ;
extern byte_ptr base_ptr ;
extern byte_ptr global_ptr ;
extern byte_ptr common_word_ptr ;
word max_blocks ;
word blocks_allocated ;
byte_ptr ptr ;
/*
** Initialise the Game Global Variables.
*/
read_header ( &data_head ) ;
if ( stop == TRUE )
return ;
resident_blocks = data_head.resident_bytes / BLOCK_SIZE ;
if ( data_head.resident_bytes % BLOCK_SIZE )
++resident_blocks ;
switch ( data_head.z_code_version )
{
case VERSION_1:
case VERSION_2:
max_blocks = STD_PAGE ( MAX_BYTES ) ;
break ;
case VERSION_3:
max_blocks = STD_PAGE ( data_head.verify_length ) ;
if ( STD_OFFSET ( data_head.verify_length ) != 0 )
++max_blocks ;
break ;
case VERSION_4:
case VERSION_5:
default:
max_blocks = PLUS_PAGE ( data_head.verify_length ) ;
if ( PLUS_OFFSET ( data_head.verify_length ) != 0 )
++max_blocks ;
break ;
}
if ((word)( blocks_allocated = allocate (max_blocks + 2)) < (word)(resident_blocks + 2))
{
/*
** There must be enough room for the resident blocks and at
** least two pages ( a program page being referenced by the
** program counter and a data page ).
*/
error ( ERR_MEMORY ) ;
display ( "Not enough memory." ) ;
}
else
{
/*
** Define Globals
*/
if (( pre_load == TRUE ) && ( blocks_allocated == ( max_blocks + 2 )))
resident_blocks = max_blocks ;
load_page ( 0,resident_blocks,base_ptr ) ;
save_blocks = data_head.save_bytes / BLOCK_SIZE ;
if ( data_head.save_bytes % BLOCK_SIZE )
++ save_blocks ;
std_obj_list = (std_object_ptr)( base_ptr + data_head.object_list ) ;
plus_obj_list = (plus_object_ptr)( base_ptr + data_head.object_list ) ;
global_ptr = base_ptr + data_head.globals ;
common_word_ptr = base_ptr + data_head.common_word ;
/*
** Initialise Page Table.
*/
ptr = base_ptr + ( (long_word)resident_blocks * BLOCK_SIZE ) ;
init_page ( ptr,( blocks_allocated - resident_blocks ) ) ;
init_input ( data_head.vocab ) ;
init_message ( data_head.z_code_version ) ;
init_opcodes ( data_head.z_code_version ) ;
seed_random () ;
}
}
/*
** Opcode Initilaisation Routines
*/
#define gosub3 plus_gosub
#define null2 null
#define null3 null
#define not2 not
#define new_opcode0 null
Void
new_opcode1 ()
{
store ( (word)0 ) ;
}
Void
init_opcodes ( version )
byte version ;
{
extern boolean enhanced ;
extern proc_ptr jmp_op0[] ;
extern proc_ptr jmp_op1[] ;
extern proc_ptr jmp_op2[] ;
extern int operands[] ;
if ( version == VERSION_3 )
{
jmp_op0[0x0C] = prt_status ;
jmp_op0[0x0D] = verify ;
if ( enhanced )
{
/*
** In the Standard Series Executor, two extra opcodes can
** be enabled for screen formatting. Some machines may not
** be able to support these extra commands ( opcodes $EA &
** $EB - corresponding to entries "split_screen" ($2A) &
** "set_current_screen" ($2B) in the array "(*jmp_op2[])()" ).
*/
jmp_op2[0x2A] = split_screen ;
jmp_op2[0x2B] = set_current_window ;
/* Level 1 patch installed -mlk */
operands[0x2A] = 1 ; /* split_screen */
operands[0x2B] = 1 ; /* set_current_window */
}
}
if (( version == VERSION_4 ) || ( version == VERSION_5 ))
{
enhanced = TRUE ;
/*
** Enhancements for existing Opcodes.
*/
jmp_op1[0x01] = plus_get_link ;
jmp_op1[0x02] = plus_get_holds ;
jmp_op1[0x03] = plus_get_loc ;
jmp_op1[0x04] = plus_get_p_len ;
jmp_op1[0x09] = plus_remove_obj ;
jmp_op1[0x0A] = plus_p_obj ;
jmp_op1[0x0D] = plus_print2 ;
jmp_op2[0x06] = plus_check_loc ;
jmp_op2[0x0A] = plus_test_attr ;
jmp_op2[0x0B] = plus_set_attr ;
jmp_op2[0x0C] = plus_clr_attr ;
jmp_op2[0x0E] = plus_transfer ;
jmp_op2[0x11] = plus_getprop ;
jmp_op2[0x12] = plus_get_prop_addr ;
jmp_op2[0x13] = plus_get_next_prop ;
jmp_op2[0x20] = plus_gosub ;
jmp_op2[0x23] = plus_put_prop ;
jmp_op2[0x27] = plus_random ;
/*
** New Opcodes.
*/
jmp_op0[0x0D] = verify ;
jmp_op1[0x08] = gosub2 ;
jmp_op2[0x19] = gosub3 ;
jmp_op2[0x2A] = split_screen ;
jmp_op2[0x2B] = set_current_window ;
jmp_op2[0x2C] = gosub3 ;
jmp_op2[0x2D] = do_clear_screen ;
jmp_op2[0x2E] = erase_line ;
jmp_op2[0x2F] = set_cursor_posn ;
jmp_op2[0x30] = null2 ;
jmp_op2[0x31] = set_text_mode ;
jmp_op2[0x32] = io_buffer_mode ;
jmp_op2[0x33] = io_mode ;
jmp_op2[0x34] = null3 ;
jmp_op2[0x35] = do_beep ;
jmp_op2[0x36] = get_key ;
jmp_op2[0x37] = plus_compare2 ;
operands[0x19] = 0 ; /* gosub3 */
operands[0x2A] = 1 ; /* split_screen */
operands[0x2B] = 1 ; /* set_current_window */
operands[0x2C] = 0 ; /* gosub3 */
operands[0x2D] = 1 ; /* do_clear_screen */
operands[0x2E] = 1 ; /* erase_line */
operands[0x2F] = 0 ; /* set_cursor_posn */
operands[0x30] = 0 ; /* null2 */
operands[0x31] = 1 ; /* set_text_mode */
operands[0x32] = 1 ; /* io_buffer_mode */
operands[0x33] = 0 ; /* io_mode */
operands[0x34] = 0 ; /* null3 */
operands[0x35] = 1 ; /* do_beep */
operands[0x36] = 0 ; /* get_key */
operands[0x37] = 0 ; /* plus_compare2 */
if ( version == VERSION_5 )
{
/*
** Enhancements for existing Opcodes.
*/
jmp_op0[0x05] = illegal_opcode ;
jmp_op0[0x06] = illegal_opcode ;
jmp_op0[0x09] = adv_pop_stack ;
jmp_op0[0x0F] = branch_true ;
jmp_op1[0x0B] = adv_rtn ;
jmp_op1[0x0F] = gosub5 ;
jmp_op2[0x19] = adv_gosub ;
jmp_op2[0x20] = adv_gosub ;
jmp_op2[0x2C] = adv_gosub ;
jmp_op2[0x37] = adv_compare2 ;
/*
** New Opcodes.
*/
jmp_op2[0x1A] = gosub4 ;
jmp_op2[0x1B] = new_opcode0 ;
jmp_op2[0x1C] = throw_away_stack_frame ;
jmp_op2[0x38] = not2 ;
jmp_op2[0x39] = gosub4 ;
jmp_op2[0x3A] = gosub4 ;
jmp_op2[0x3B] = parse ;
jmp_op2[0x3C] = encrypt ;
jmp_op2[0x3D] = block_copy ;
jmp_op2[0x3E] = print_text ;
jmp_op2[0x3F] = num_local_params ;
jmp_op2[0x40] = save_game ;
jmp_op2[0x41] = restore_game ;
jmp_op2[0x42] = logical_shift ;
jmp_op2[0x43] = arithmetic_shift ;
jmp_op2[0x44] = new_opcode1 ;
jmp_op2[0x45] = clear_flag ;
jmp_op2[0x46] = test_byte_array ;
jmp_op2[0x47] = set_flag ;
jmp_op2[0x48] = new_opcode0 ;
jmp_op2[0x49] = new_opcode1 ;
jmp_op2[0x4A] = new_opcode1 ;
operands[0x1A] = 0 ; /* gosub4 */
operands[0x1B] = 2 ; /* new_opcode0 */
operands[0x1C] = 2 ; /* throw_away_stack_frame */
operands[0x38] = 1 ; /* not2 */
operands[0x39] = 0 ; /* gosub4 */
operands[0x3A] = 0 ; /* gosub4 */
operands[0x3B] = 0 ; /* parse */
operands[0x3C] = 4 ; /* encrypt */
operands[0x3D] = 0 ; /* block_copy */
operands[0x3E] = 0 ; /* print_text */
operands[0x3F] = 1 ; /* num_local_params */
operands[0x40] = 0 ; /* save_game */
operands[0x41] = 0 ; /* restore_game */
operands[0x42] = 2 ; /* logical_shift */
operands[0x43] = 2 ; /* arithmetic_shift */
operands[0x44] = 1 ; /* new_opcode1 */
operands[0x45] = 0 ; /* clear_flag */
operands[0x46] = 2 ; /* test_byte_array */
operands[0x47] = 0 ; /* set_flag */
operands[0x48] = 2 ; /* new_opcode0 */
operands[0x49] = 2 ; /* new_opcode1 */
operands[0x4A] = 0 ; /* new_opcode1 */
}
}
}
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