1 files changed, 0 insertions, 573 deletions
diff --git a/src/scheme/ao_scheme_eval.c b/src/scheme/ao_scheme_eval.c
deleted file mode 100644
index 9536cb91..00000000
--- a/src/scheme/ao_scheme_eval.c
+++ /dev/null
@@ -1,573 +0,0 @@
-/*
- * Copyright © 2016 Keith Packard <keithp@keithp.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- */
-
-#include "ao_scheme.h"
-#include <assert.h>
-
-struct ao_scheme_stack		*ao_scheme_stack;
-ao_poly				ao_scheme_v;
-
-ao_poly
-ao_scheme_set_cond(struct ao_scheme_cons *c)
-{
-	ao_scheme_stack->state = eval_cond;
-	ao_scheme_stack->sexprs = ao_scheme_cons_poly(c);
-	return AO_SCHEME_NIL;
-}
-
-static int
-func_type(ao_poly func)
-{
-	if (func == AO_SCHEME_NIL)
-		return ao_scheme_error(AO_SCHEME_INVALID, "func is nil");
-	switch (ao_scheme_poly_type(func)) {
-	case AO_SCHEME_BUILTIN:
-		return ao_scheme_poly_builtin(func)->args & AO_SCHEME_FUNC_MASK;
-	case AO_SCHEME_LAMBDA:
-		return ao_scheme_poly_lambda(func)->args;
-	case AO_SCHEME_STACK:
-		return AO_SCHEME_FUNC_LAMBDA;
-	default:
-		ao_scheme_error(AO_SCHEME_INVALID, "not a func");
-		return -1;
-	}
-}
-
-/*
- * Flattened eval to avoid stack issues
- */
-
-/*
- * Evaluate an s-expression
- *
- * For a list, evaluate all of the elements and
- * then execute the resulting function call.
- *
- * Each element of the list is evaluated in
- * a clean stack context.
- *
- * The current stack state is set to 'formal' so that
- * when the evaluation is complete, the value
- * will get appended to the values list.
- *
- * For other types, compute the value directly.
- */
-
-static int
-ao_scheme_eval_sexpr(void)
-{
-	DBGI("sexpr: %v\n", ao_scheme_v);
-	switch (ao_scheme_poly_type(ao_scheme_v)) {
-	case AO_SCHEME_CONS:
-		if (ao_scheme_v == AO_SCHEME_NIL) {
-			if (!ao_scheme_stack->values) {
-				/*
-				 * empty list evaluates to empty list
-				 */
-				ao_scheme_v = AO_SCHEME_NIL;
-				ao_scheme_stack->state = eval_val;
-			} else {
-				/*
-				 * done with arguments, go execute it
-				 */
-				ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->values)->car;
-				ao_scheme_stack->state = eval_exec;
-			}
-		} else {
-			if (!ao_scheme_stack->values)
-				ao_scheme_stack->list = ao_scheme_v;
-			/*
-			 * Evaluate another argument and then switch
-			 * to 'formal' to add the value to the values
-			 * list
-			 */
-			ao_scheme_stack->sexprs = ao_scheme_v;
-			ao_scheme_stack->state = eval_formal;
-			if (!ao_scheme_stack_push())
-				return 0;
-			/*
-			 * push will reset the state to 'sexpr', which
-			 * will evaluate the expression
-			 */
-			ao_scheme_v = ao_scheme_poly_cons(ao_scheme_v)->car;
-		}
-		break;
-	case AO_SCHEME_ATOM:
-		DBGI("..frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-		ao_scheme_v = ao_scheme_atom_get(ao_scheme_v);
-		/* fall through */
-	default:
-		ao_scheme_stack->state = eval_val;
-		break;
-	}
-	DBGI(".. result "); DBG_POLY(ao_scheme_v); DBG("\n");
-	return 1;
-}
-
-/*
- * A value has been computed.
- *
- * If the value was computed from a macro,
- * then we want to reset the current context
- * to evaluate the macro result again.
- *
- * If not a macro, then pop the stack.
- * If the stack is empty, we're done.
- * Otherwise, the stack will contain
- * the next state.
- */
-
-static int
-ao_scheme_eval_val(void)
-{
-	DBGI("val: "); DBG_POLY(ao_scheme_v); DBG("\n");
-	/*
-	 * Value computed, pop the stack
-	 * to figure out what to do with the value
-	 */
-	ao_scheme_stack_pop();
-	DBGI("..state %d\n", ao_scheme_stack ? ao_scheme_stack->state : -1);
-	return 1;
-}
-
-/*
- * A formal has been computed.
- *
- * If this is the first formal, then check to see if we've got a
- * lamda, macro or nlambda.
- *
- * For lambda, go compute another formal.  This will terminate
- * when the sexpr state sees nil.
- *
- * For macro/nlambda, we're done, so move the sexprs into the values
- * and go execute it.
- *
- * Macros have an additional step of saving a stack frame holding the
- * macro value execution context, which then gets the result of the
- * macro to run
- */
-
-static int
-ao_scheme_eval_formal(void)
-{
-	ao_poly			formal;
-	struct ao_scheme_stack	*prev;
-
-	DBGI("formal: "); DBG_POLY(ao_scheme_v); DBG("\n");
-
-	/* Check what kind of function we've got */
-	if (!ao_scheme_stack->values) {
-		switch (func_type(ao_scheme_v)) {
-		case AO_SCHEME_FUNC_LAMBDA:
-			DBGI(".. lambda\n");
-			break;
-		case AO_SCHEME_FUNC_MACRO:
-			/* Evaluate the result once more */
-			ao_scheme_stack->state = eval_macro;
-			if (!ao_scheme_stack_push())
-				return 0;
-
-			/* After the function returns, take that
-			 * value and re-evaluate it
-			 */
-			prev = ao_scheme_poly_stack(ao_scheme_stack->prev);
-			ao_scheme_stack->sexprs = prev->sexprs;
-
-			DBGI(".. start macro\n");
-			DBGI("\t.. sexprs       "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-			DBGI("\t.. values       "); DBG_POLY(ao_scheme_stack->values); DBG("\n");
-			DBG_FRAMES();
-
-			/* fall through ... */
-		case AO_SCHEME_FUNC_NLAMBDA:
-			DBGI(".. nlambda or macro\n");
-
-			/* use the raw sexprs as values */
-			ao_scheme_stack->values = ao_scheme_stack->sexprs;
-			ao_scheme_stack->values_tail = AO_SCHEME_NIL;
-			ao_scheme_stack->state = eval_exec;
-
-			/* ready to execute now */
-			return 1;
-		case -1:
-			return 0;
-		}
-	}
-
-	/* Append formal to list of values */
-	formal = ao_scheme_cons(ao_scheme_v, AO_SCHEME_NIL);
-	if (!formal)
-		return 0;
-
-	if (ao_scheme_stack->values_tail)
-		ao_scheme_poly_cons(ao_scheme_stack->values_tail)->cdr = formal;
-	else
-		ao_scheme_stack->values = formal;
-	ao_scheme_stack->values_tail = formal;
-
-	DBGI(".. values "); DBG_POLY(ao_scheme_stack->values); DBG("\n");
-
-	/*
-	 * Step to the next argument, if this is last, then
-	 * 'sexpr' will end up switching to 'exec'
-	 */
-	ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->sexprs)->cdr;
-
-	ao_scheme_stack->state = eval_sexpr;
-
-	DBGI(".. "); DBG_POLY(ao_scheme_v); DBG("\n");
-	return 1;
-}
-
-/*
- * Start executing a function call
- *
- * Most builtins are easy, just call the function.
- * 'cond' is magic; it sticks the list of clauses
- * in 'sexprs' and switches to 'cond' state. That
- * bit of magic is done in ao_scheme_set_cond.
- *
- * Lambdas build a new frame to hold the locals and
- * then re-use the current stack context to evaluate
- * the s-expression from the lambda.
- */
-
-static int
-ao_scheme_eval_exec(void)
-{
-	ao_poly v;
-	struct ao_scheme_builtin	*builtin;
-
-	DBGI("exec: "); DBG_POLY(ao_scheme_v); DBG(" values "); DBG_POLY(ao_scheme_stack->values); DBG ("\n");
-	ao_scheme_stack->sexprs = AO_SCHEME_NIL;
-	switch (ao_scheme_poly_type(ao_scheme_v)) {
-	case AO_SCHEME_BUILTIN:
-		ao_scheme_stack->state = eval_val;
-		builtin = ao_scheme_poly_builtin(ao_scheme_v);
-		v = ao_scheme_func(builtin) (
-			ao_scheme_poly_cons(ao_scheme_poly_cons(ao_scheme_stack->values)->cdr));
-		DBG_DO(if (!ao_scheme_exception && ao_scheme_poly_builtin(ao_scheme_v)->func == builtin_set) {
-				struct ao_scheme_cons *cons = ao_scheme_poly_cons(ao_scheme_stack->values);
-				ao_poly atom = ao_scheme_arg(cons, 1);
-				ao_poly val = ao_scheme_arg(cons, 2);
-				DBGI("set "); DBG_POLY(atom); DBG(" = "); DBG_POLY(val); DBG("\n");
-			});
-		builtin = ao_scheme_poly_builtin(ao_scheme_v);
-		if (builtin && (builtin->args & AO_SCHEME_FUNC_FREE_ARGS) && !ao_scheme_stack_marked(ao_scheme_stack)) {
-			struct ao_scheme_cons *cons = ao_scheme_poly_cons(ao_scheme_stack->values);
-			ao_scheme_stack->values = AO_SCHEME_NIL;
-			ao_scheme_cons_free(cons);
-		}
-
-		ao_scheme_v = v;
-		if (ao_scheme_stack->state != eval_exec) {
-			ao_scheme_stack->values = AO_SCHEME_NIL;
-			ao_scheme_stack->values_tail = AO_SCHEME_NIL;
-		}
-		DBGI(".. result "); DBG_POLY(ao_scheme_v); DBG ("\n");
-		DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-		break;
-	case AO_SCHEME_LAMBDA:
-		DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-		ao_scheme_stack->state = eval_begin;
-		v = ao_scheme_lambda_eval();
-		ao_scheme_stack->sexprs = v;
-		ao_scheme_stack->values = AO_SCHEME_NIL;
-		ao_scheme_stack->values_tail = AO_SCHEME_NIL;
-		DBGI(".. sexprs "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-		DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-		break;
-	case AO_SCHEME_STACK:
-		DBGI(".. stack "); DBG_POLY(ao_scheme_v); DBG("\n");
-		ao_scheme_v = ao_scheme_stack_eval();
-		DBGI(".. value "); DBG_POLY(ao_scheme_v); DBG("\n");
-		DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-		break;
-	}
-	return 1;
-}
-
-/*
- * Finish setting up the apply evaluation
- *
- * The value is the list to execute
- */
-static int
-ao_scheme_eval_apply(void)
-{
-	struct ao_scheme_cons	*cons = ao_scheme_poly_cons(ao_scheme_v);
-	struct ao_scheme_cons	*cdr, *prev;
-
-	/* Glue the arguments into the right shape. That's all but the last
-	 * concatenated onto the last
-	 */
-	cdr = cons;
-	for (;;) {
-		prev = cdr;
-		cdr = ao_scheme_poly_cons(prev->cdr);
-		if (cdr->cdr == AO_SCHEME_NIL)
-			break;
-	}
-	DBGI("before mangling: "); DBG_POLY(ao_scheme_v); DBG("\n");
-	prev->cdr = cdr->car;
-	ao_scheme_stack->values = ao_scheme_v;
-	ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->values)->car;
-	DBGI("apply: "); DBG_POLY(ao_scheme_stack->values); DBG ("\n");
-	ao_scheme_stack->state = eval_exec;
-	ao_scheme_stack_mark(ao_scheme_stack);
-	return 1;
-}
-
-/*
- * Start evaluating the next cond clause
- *
- * If the list of clauses is empty, then
- * the result of the cond is nil.
- *
- * Otherwise, set the current stack state to 'cond_test' and create a
- * new stack context to evaluate the test s-expression. Once that's
- * complete, we'll land in 'cond_test' to finish the clause.
- */
-static int
-ao_scheme_eval_cond(void)
-{
-	DBGI("cond: "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-	DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-	DBGI(".. saved frame "); DBG_POLY(ao_scheme_stack->frame); DBG("\n");
-	if (!ao_scheme_stack->sexprs) {
-		ao_scheme_v = _ao_scheme_bool_false;
-		ao_scheme_stack->state = eval_val;
-	} else {
-		ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->sexprs)->car;
-		if (!ao_scheme_is_pair(ao_scheme_v)) {
-			ao_scheme_error(AO_SCHEME_INVALID, "invalid cond clause");
-			return 0;
-		}
-		ao_scheme_v = ao_scheme_poly_cons(ao_scheme_v)->car;
-		if (ao_scheme_v == _ao_scheme_atom_else)
-			ao_scheme_v = _ao_scheme_bool_true;
-		ao_scheme_stack->state = eval_cond_test;
-		if (!ao_scheme_stack_push())
-			return 0;
-	}
-	return 1;
-}
-
-/*
- * Finish a cond clause.
- *
- * Check the value from the test expression, if
- * non-nil, then set up to evaluate the value expression.
- *
- * Otherwise, step to the next clause and go back to the 'cond'
- * state
- */
-static int
-ao_scheme_eval_cond_test(void)
-{
-	DBGI("cond_test: "); DBG_POLY(ao_scheme_v); DBG(" sexprs "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-	DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-	DBGI(".. saved frame "); DBG_POLY(ao_scheme_stack->frame); DBG("\n");
-	if (ao_scheme_v != _ao_scheme_bool_false) {
-		struct ao_scheme_cons *car = ao_scheme_poly_cons(ao_scheme_poly_cons(ao_scheme_stack->sexprs)->car);
-		ao_poly c = car->cdr;
-
-		if (c) {
-			ao_scheme_stack->state = eval_begin;
-			ao_scheme_stack->sexprs = c;
-		} else
-			ao_scheme_stack->state = eval_val;
-	} else {
-		ao_scheme_stack->sexprs = ao_scheme_poly_cons(ao_scheme_stack->sexprs)->cdr;
-		DBGI("next cond: "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-		ao_scheme_stack->state = eval_cond;
-	}
-	return 1;
-}
-
-/*
- * Evaluate a list of sexprs, returning the value from the last one.
- *
- * ao_scheme_begin records the list in stack->sexprs, so we just need to
- * walk that list. Set ao_scheme_v to the car of the list and jump to
- * eval_sexpr. When that's done, it will land in eval_val. For all but
- * the last, leave a stack frame with eval_begin set so that we come
- * back here. For the last, don't add a stack frame so that we can
- * just continue on.
- */
-static int
-ao_scheme_eval_begin(void)
-{
-	DBGI("begin: "); DBG_POLY(ao_scheme_v); DBG(" sexprs "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-	DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-	DBGI(".. saved frame "); DBG_POLY(ao_scheme_stack->frame); DBG("\n");
-
-	if (!ao_scheme_stack->sexprs) {
-		ao_scheme_v = AO_SCHEME_NIL;
-		ao_scheme_stack->state = eval_val;
-	} else {
-		ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->sexprs)->car;
-		ao_scheme_stack->sexprs = ao_scheme_poly_cons(ao_scheme_stack->sexprs)->cdr;
-
-		/* If there are more sexprs to do, then come back here, otherwise
-		 * return the value of the last one by just landing in eval_sexpr
-		 */
-		if (ao_scheme_stack->sexprs) {
-			ao_scheme_stack->state = eval_begin;
-			if (!ao_scheme_stack_push())
-				return 0;
-		}
-		ao_scheme_stack->state = eval_sexpr;
-	}
-	return 1;
-}
-
-/*
- * Conditionally execute a list of sexprs while the first is true
- */
-static int
-ao_scheme_eval_while(void)
-{
-	DBGI("while: "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-	DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-	DBGI(".. saved frame "); DBG_POLY(ao_scheme_stack->frame); DBG("\n");
-
-	ao_scheme_stack->values = ao_scheme_v;
-	if (!ao_scheme_stack->sexprs) {
-		ao_scheme_v = AO_SCHEME_NIL;
-		ao_scheme_stack->state = eval_val;
-	} else {
-		ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->sexprs)->car;
-		ao_scheme_stack->state = eval_while_test;
-		if (!ao_scheme_stack_push())
-			return 0;
-	}
-	return 1;
-}
-
-/*
- * Check the while condition, terminate the loop if nil. Otherwise keep going
- */
-static int
-ao_scheme_eval_while_test(void)
-{
-	DBGI("while_test: "); DBG_POLY(ao_scheme_v); DBG(" sexprs "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-	DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
-	DBGI(".. saved frame "); DBG_POLY(ao_scheme_stack->frame); DBG("\n");
-
-	if (ao_scheme_v != _ao_scheme_bool_false) {
-		ao_scheme_stack->values = ao_scheme_v;
-		ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->sexprs)->cdr;
-		ao_scheme_stack->state = eval_while;
-		if (!ao_scheme_stack_push())
-			return 0;
-		ao_scheme_stack->state = eval_begin;
-		ao_scheme_stack->sexprs = ao_scheme_v;
-	}
-	else
-	{
-		ao_scheme_stack->state = eval_val;
-		ao_scheme_v = ao_scheme_stack->values;
-	}
-	return 1;
-}
-
-/*
- * Replace the original sexpr with the macro expansion, then
- * execute that
- */
-static int
-ao_scheme_eval_macro(void)
-{
-	DBGI("macro: "); DBG_POLY(ao_scheme_v); DBG(" sexprs "); DBG_POLY(ao_scheme_stack->sexprs); DBG("\n");
-
-	if (ao_scheme_v == AO_SCHEME_NIL)
-		ao_scheme_abort();
-	if (ao_scheme_is_cons(ao_scheme_v)) {
-		*ao_scheme_poly_cons(ao_scheme_stack->sexprs) = *ao_scheme_poly_cons(ao_scheme_v);
-		ao_scheme_v = ao_scheme_stack->sexprs;
-		DBGI("sexprs rewritten to: "); DBG_POLY(ao_scheme_v); DBG("\n");
-	}
-	ao_scheme_stack->sexprs = AO_SCHEME_NIL;
-	ao_scheme_stack->state = eval_sexpr;
-	return 1;
-}
-
-static int (*const evals[])(void) = {
-	[eval_sexpr] = ao_scheme_eval_sexpr,
-	[eval_val] = ao_scheme_eval_val,
-	[eval_formal] = ao_scheme_eval_formal,
-	[eval_exec] = ao_scheme_eval_exec,
-	[eval_apply] = ao_scheme_eval_apply,
-	[eval_cond] = ao_scheme_eval_cond,
-	[eval_cond_test] = ao_scheme_eval_cond_test,
-	[eval_begin] = ao_scheme_eval_begin,
-	[eval_while] = ao_scheme_eval_while,
-	[eval_while_test] = ao_scheme_eval_while_test,
-	[eval_macro] = ao_scheme_eval_macro,
-};
-
-const char * const ao_scheme_state_names[] = {
-	[eval_sexpr] = "sexpr",
-	[eval_val] = "val",
-	[eval_formal] = "formal",
-	[eval_exec] = "exec",
-	[eval_apply] = "apply",
-	[eval_cond] = "cond",
-	[eval_cond_test] = "cond_test",
-	[eval_begin] = "begin",
-	[eval_while] = "while",
-	[eval_while_test] = "while_test",
-	[eval_macro] = "macro",
-};
-
-#ifdef AO_SCHEME_FEATURE_SAVE
-/*
- * Called at restore time to reset all execution state
- */
-
-void
-ao_scheme_eval_clear_globals(void)
-{
-	ao_scheme_stack = NULL;
-	ao_scheme_frame_current = NULL;
-	ao_scheme_v = AO_SCHEME_NIL;
-}
-
-int
-ao_scheme_eval_restart(void)
-{
-	return ao_scheme_stack_push();
-}
-#endif /* AO_SCHEME_FEATURE_SAVE */
-
-ao_poly
-ao_scheme_eval(ao_poly _v)
-{
-	ao_scheme_v = _v;
-
-	ao_scheme_frame_init();
-
-	if (!ao_scheme_stack_push())
-		return AO_SCHEME_NIL;
-
-	while (ao_scheme_stack) {
-		if (!(*evals[ao_scheme_stack->state])() || ao_scheme_exception)
-			break;
-	}
-	DBG_DO(if (ao_scheme_frame_current) {DBGI("frame left as "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");});
-	ao_scheme_stack = NULL;
-	ao_scheme_frame_current = NULL;
-	return ao_scheme_v;
-}