1 files changed, 330 insertions, 0 deletions
diff --git a/src/scheme/ao_scheme_frame.c b/src/scheme/ao_scheme_frame.c
new file mode 100644
index 00000000..e5d481e7
--- /dev/null
+++ b/src/scheme/ao_scheme_frame.c
@@ -0,0 +1,330 @@
+/*
+ * 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"
+
+static inline int
+frame_vals_num_size(int num)
+{
+	return sizeof (struct ao_scheme_frame_vals) + num * sizeof (struct ao_scheme_val);
+}
+
+static int
+frame_vals_size(void *addr)
+{
+	struct ao_scheme_frame_vals	*vals = addr;
+	return frame_vals_num_size(vals->size);
+}
+
+static void
+frame_vals_mark(void *addr)
+{
+	struct ao_scheme_frame_vals	*vals = addr;
+	int				f;
+
+	for (f = 0; f < vals->size; f++) {
+		struct ao_scheme_val	*v = &vals->vals[f];
+
+		ao_scheme_poly_mark(v->val, 0);
+		MDBG_MOVE("frame mark atom %s %d val %d at %d    ",
+			  ao_scheme_poly_atom(v->atom)->name,
+			  MDBG_OFFSET(ao_scheme_ref(v->atom)),
+			  MDBG_OFFSET(ao_scheme_ref(v->val)), f);
+		MDBG_DO(ao_scheme_poly_write(v->val));
+		MDBG_DO(printf("\n"));
+	}
+}
+
+static void
+frame_vals_move(void *addr)
+{
+	struct ao_scheme_frame_vals	*vals = addr;
+	int				f;
+
+	for (f = 0; f < vals->size; f++) {
+		struct ao_scheme_val	*v = &vals->vals[f];
+
+		ao_scheme_poly_move(&v->atom, 0);
+		ao_scheme_poly_move(&v->val, 0);
+		MDBG_MOVE("frame move atom %s %d val %d at %d\n",
+			  ao_scheme_poly_atom(v->atom)->name,
+			  MDBG_OFFSET(ao_scheme_ref(v->atom)),
+			  MDBG_OFFSET(ao_scheme_ref(v->val)), f);
+	}
+}
+
+const struct ao_scheme_type ao_scheme_frame_vals_type = {
+	.mark = frame_vals_mark,
+	.size = frame_vals_size,
+	.move = frame_vals_move,
+	.name = "frame_vals"
+};
+
+static int
+frame_size(void *addr)
+{
+	(void) addr;
+	return sizeof (struct ao_scheme_frame);
+}
+
+static void
+frame_mark(void *addr)
+{
+	struct ao_scheme_frame	*frame = addr;
+
+	for (;;) {
+		MDBG_MOVE("frame mark %d\n", MDBG_OFFSET(frame));
+		if (!AO_SCHEME_IS_POOL(frame))
+			break;
+		ao_scheme_poly_mark(frame->vals, 0);
+		frame = ao_scheme_poly_frame(frame->prev);
+		MDBG_MOVE("frame next %d\n", MDBG_OFFSET(frame));
+		if (!frame)
+			break;
+		if (ao_scheme_mark_memory(&ao_scheme_frame_type, frame))
+			break;
+	}
+}
+
+static void
+frame_move(void *addr)
+{
+	struct ao_scheme_frame	*frame = addr;
+
+	for (;;) {
+		struct ao_scheme_frame	*prev;
+		int			ret;
+
+		MDBG_MOVE("frame move %d\n", MDBG_OFFSET(frame));
+		if (!AO_SCHEME_IS_POOL(frame))
+			break;
+		ao_scheme_poly_move(&frame->vals, 0);
+		prev = ao_scheme_poly_frame(frame->prev);
+		if (!prev)
+			break;
+		ret = ao_scheme_move_memory(&ao_scheme_frame_type, (void **) &prev);
+		if (prev != ao_scheme_poly_frame(frame->prev)) {
+			MDBG_MOVE("frame prev moved from %d to %d\n",
+				  MDBG_OFFSET(ao_scheme_poly_frame(frame->prev)),
+				  MDBG_OFFSET(prev));
+			frame->prev = ao_scheme_frame_poly(prev);
+		}
+		if (ret)
+			break;
+		frame = prev;
+	}
+}
+
+const struct ao_scheme_type ao_scheme_frame_type = {
+	.mark = frame_mark,
+	.size = frame_size,
+	.move = frame_move,
+	.name = "frame",
+};
+
+void
+ao_scheme_frame_write(ao_poly p)
+{
+	struct ao_scheme_frame		*frame = ao_scheme_poly_frame(p);
+	struct ao_scheme_frame_vals	*vals = ao_scheme_poly_frame_vals(frame->vals);
+	int				f;
+
+	printf ("{");
+	if (frame) {
+		if (frame->type & AO_SCHEME_FRAME_PRINT)
+			printf("recurse...");
+		else {
+			frame->type |= AO_SCHEME_FRAME_PRINT;
+			for (f = 0; f < frame->num; f++) {
+				if (f != 0)
+					printf(", ");
+				ao_scheme_poly_write(vals->vals[f].atom);
+				printf(" = ");
+				ao_scheme_poly_write(vals->vals[f].val);
+			}
+			if (frame->prev)
+				ao_scheme_poly_write(frame->prev);
+			frame->type &= ~AO_SCHEME_FRAME_PRINT;
+		}
+	}
+	printf("}");
+}
+
+static int
+ao_scheme_frame_find(struct ao_scheme_frame *frame, int top, ao_poly atom)
+{
+	struct ao_scheme_frame_vals	*vals = ao_scheme_poly_frame_vals(frame->vals);
+	int 				l = 0;
+	int 				r = top - 1;
+
+	while (l <= r) {
+		int m = (l + r) >> 1;
+		if (vals->vals[m].atom < atom)
+			l = m + 1;
+		else
+			r = m - 1;
+	}
+	return l;
+}
+
+ao_poly *
+ao_scheme_frame_ref(struct ao_scheme_frame *frame, ao_poly atom)
+{
+	struct ao_scheme_frame_vals	*vals = ao_scheme_poly_frame_vals(frame->vals);
+	int				l = ao_scheme_frame_find(frame, frame->num, atom);
+
+	if (l >= frame->num)
+		return NULL;
+
+	if (vals->vals[l].atom != atom)
+		return NULL;
+	return &vals->vals[l].val;
+}
+
+struct ao_scheme_frame	*ao_scheme_frame_free_list[AO_SCHEME_FRAME_FREE];
+
+static struct ao_scheme_frame_vals *
+ao_scheme_frame_vals_new(int num)
+{
+	struct ao_scheme_frame_vals	*vals;
+
+	vals = ao_scheme_alloc(frame_vals_num_size(num));
+	if (!vals)
+		return NULL;
+	vals->type = AO_SCHEME_FRAME_VALS;
+	vals->size = num;
+	memset(vals->vals, '\0', num * sizeof (struct ao_scheme_val));
+	return vals;
+}
+
+struct ao_scheme_frame *
+ao_scheme_frame_new(int num)
+{
+	struct ao_scheme_frame		*frame;
+	struct ao_scheme_frame_vals	*vals;
+
+	if (num < AO_SCHEME_FRAME_FREE && (frame = ao_scheme_frame_free_list[num])) {
+		ao_scheme_frame_free_list[num] = ao_scheme_poly_frame(frame->prev);
+		vals = ao_scheme_poly_frame_vals(frame->vals);
+	} else {
+		frame = ao_scheme_alloc(sizeof (struct ao_scheme_frame));
+		if (!frame)
+			return NULL;
+		frame->type = AO_SCHEME_FRAME;
+		frame->num = 0;
+		frame->prev = AO_SCHEME_NIL;
+		frame->vals = AO_SCHEME_NIL;
+		ao_scheme_frame_stash(0, frame);
+		vals = ao_scheme_frame_vals_new(num);
+		frame = ao_scheme_frame_fetch(0);
+		if (!vals)
+			return NULL;
+		frame->vals = ao_scheme_frame_vals_poly(vals);
+		frame->num = num;
+	}
+	frame->prev = AO_SCHEME_NIL;
+	return frame;
+}
+
+ao_poly
+ao_scheme_frame_mark(struct ao_scheme_frame *frame)
+{
+	if (!frame)
+		return AO_SCHEME_NIL;
+	frame->type |= AO_SCHEME_FRAME_MARK;
+	return ao_scheme_frame_poly(frame);
+}
+
+void
+ao_scheme_frame_free(struct ao_scheme_frame *frame)
+{
+	if (frame && !ao_scheme_frame_marked(frame)) {
+		int	num = frame->num;
+		if (num < AO_SCHEME_FRAME_FREE) {
+			struct ao_scheme_frame_vals	*vals;
+
+			vals = ao_scheme_poly_frame_vals(frame->vals);
+			memset(vals->vals, '\0', vals->size * sizeof (struct ao_scheme_val));
+			frame->prev = ao_scheme_frame_poly(ao_scheme_frame_free_list[num]);
+			ao_scheme_frame_free_list[num] = frame;
+		}
+	}
+}
+
+static struct ao_scheme_frame *
+ao_scheme_frame_realloc(struct ao_scheme_frame *frame, int new_num)
+{
+	struct ao_scheme_frame_vals	*vals;
+	struct ao_scheme_frame_vals	*new_vals;
+	int				copy;
+
+	if (new_num == frame->num)
+		return frame;
+	ao_scheme_frame_stash(0, frame);
+	new_vals = ao_scheme_frame_vals_new(new_num);
+	frame = ao_scheme_frame_fetch(0);
+	if (!new_vals)
+		return NULL;
+	vals = ao_scheme_poly_frame_vals(frame->vals);
+	copy = new_num;
+	if (copy > frame->num)
+		copy = frame->num;
+	memcpy(new_vals->vals, vals->vals, copy * sizeof (struct ao_scheme_val));
+	frame->vals = ao_scheme_frame_vals_poly(new_vals);
+	frame->num = new_num;
+	return frame;
+}
+
+void
+ao_scheme_frame_bind(struct ao_scheme_frame *frame, int num, ao_poly atom, ao_poly val)
+{
+	struct ao_scheme_frame_vals	*vals = ao_scheme_poly_frame_vals(frame->vals);
+	int 				l = ao_scheme_frame_find(frame, num, atom);
+
+	memmove(&vals->vals[l+1],
+		&vals->vals[l],
+		(num - l) * sizeof (struct ao_scheme_val));
+	vals->vals[l].atom = atom;
+	vals->vals[l].val = val;
+}
+
+ao_poly
+ao_scheme_frame_add(struct ao_scheme_frame *frame, ao_poly atom, ao_poly val)
+{
+	ao_poly *ref = frame ? ao_scheme_frame_ref(frame, atom) : NULL;
+
+	if (!ref) {
+		int f = frame->num;
+		ao_scheme_poly_stash(0, atom);
+		ao_scheme_poly_stash(1, val);
+		frame = ao_scheme_frame_realloc(frame, f + 1);
+		val = ao_scheme_poly_fetch(1);
+		atom = ao_scheme_poly_fetch(0);
+		if (!frame)
+			return AO_SCHEME_NIL;
+		ao_scheme_frame_bind(frame, frame->num - 1, atom, val);
+	} else
+		*ref = val;
+	return val;
+}
+
+struct ao_scheme_frame	*ao_scheme_frame_global;
+struct ao_scheme_frame	*ao_scheme_frame_current;
+
+void
+ao_scheme_frame_init(void)
+{
+	if (!ao_scheme_frame_global)
+		ao_scheme_frame_global = ao_scheme_frame_new(0);
+}