post-scarcity/src/c/environment/environment.c
2026-04-16 00:22:24 +01:00

89 lines
2.6 KiB
C

/**
* environment/environment.c
*
* Initialise a MINIMAL environment.
*
* (c) 2026 Simon Brooke <simon@journeyman.cc>
* Licensed under GPL version 2.0, or, at your option, any later version.
*/
#include <stdbool.h>
#include "debug.h"
#include "memory/memory.h"
#include "memory/node.h"
#include "memory/pointer.h"
#include "memory/pso.h"
#include "memory/pso2.h"
#include "memory/tags.h"
#include "ops/bind.h"
#include "ops/string_ops.h"
#include "payloads/cons.h"
#include "payloads/exception.h"
#include "payloads/psse_string.h"
/**
* @brief Flag to prevent re-initialisation.
*/
bool environment_initialised = false;
/**
* @brief Initialise a minimal environment, so that Lisp can be bootstrapped.
*
* @param node theindex of the node we are initialising.
* @return struct pso_pointer t on success, else an exception.
*/
struct pso_pointer initialise_environment( uint32_t node ) {
struct pso_pointer result = initialise_memory( node );
if ( !exceptionp( result ) ) {
debug_print( L"Initialising `nil`... ", DEBUG_BOOTSTRAP, 0);
struct pso_pointer n = allocate( NILTAG, 2 );
if ( ( n.page == 0 ) && ( n.offset == 0 ) ) {
struct pso2 *object = pointer_to_object( n );
object->payload.cons.car = nil;
object->payload.cons.cdr = nil;
nil = n;
debug_print( L"success\n", DEBUG_BOOTSTRAP, 0);
} else {
result =
make_exception( c_string_to_lisp_string
( L"Unexpected cell while allocating `nil`." ),
nil, n );
debug_print( L"fail\n", DEBUG_BOOTSTRAP, 0);
}
}
if ( !exceptionp( result ) ) {
debug_print( L"Initialising `t`... ", DEBUG_BOOTSTRAP, 0);
struct pso_pointer n = allocate( TRUETAG, 2 );
if ( ( n.page == 0 ) && ( n.offset == 1 ) ) {
struct pso2 *object = pointer_to_object( n );
object->payload.string.character = L't';
object->payload.cons.cdr = t;
t = n;
debug_print( L"success\n", DEBUG_BOOTSTRAP, 0);
} else {
result =
make_exception( c_string_to_lisp_string
( L"Unexpected cell while allocating `t`." ),
nil, n );
debug_print( L"fail\n", DEBUG_BOOTSTRAP, 0);
}
}
if ( !exceptionp( result ) ) {
result = c_bind( c_string_to_lisp_symbol( L"nil" ), nil, nil );
result = c_bind( c_string_to_lisp_symbol( L"t" ), t, result );
environment_initialised = true;
}
return result;
}