1 files changed, 481 insertions, 0 deletions
diff --git a/awk/uxn/ref/uxnasm.c b/awk/uxn/ref/uxnasm.c
new file mode 100644
index 0000000..f25d6ce
--- /dev/null
+++ b/awk/uxn/ref/uxnasm.c
@@ -0,0 +1,481 @@
+#include <stdio.h>
+
+/*
+Copyright (c) 2021-2024 Devine Lu Linvega, Andrew Alderwick
+
+Permission to use, copy, modify, and distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE.
+*/
+
+/* clang-format off */
+
+#define PAGE 0x0100
+#define ishex(x) (shex(x) >= 0)
+#define isopc(x) (findopcode(x) || scmp(x, "BRK", 4))
+#define isinvalid(x) (!x[0] || ishex(x) || isopc(x) || find(runes, x[0]) >= 0)
+#define writeshort(x) (writebyte(x >> 8, ctx) && writebyte(x & 0xff, ctx))
+#define findlabel(x) finditem(x, labels, labels_len)
+#define findmacro(x) finditem(x, macros, macro_len)
+#define error_top(id, msg) !printf("%s: %s\n", id, msg)
+#define error_asm(id) !printf("%s: %s in @%s, %s:%d.\n", id, token, scope, ctx->path, ctx->line)
+#define error_ref(id) !printf("%s: %s, %s:%d\n", id, r->name, r->data, r->line)
+
+typedef unsigned char Uint8;
+typedef signed char Sint8;
+typedef unsigned short Uint16;
+typedef struct { int line; char *path; } Context;
+typedef struct { char *name, rune, *data; Uint16 addr, refs, line; } Item;
+
+static int ptr, length;
+static char token[0x30], scope[0x40], lambda[0x05];
+static char dict[0x8000], *dictnext = dict;
+static Uint8 data[0x10000], lambda_stack[0x100], lambda_ptr, lambda_len;
+static Uint16 labels_len, refs_len, macro_len;
+static Item labels[0x400], refs[0x1000], macros[0x100];
+
+static char *runes = "|$@&,_.-;=!?#\"%~";
+static char *hexad = "0123456789abcdef";
+static char ops[][4] = {
+	"LIT", "INC", "POP", "NIP", "SWP", "ROT", "DUP", "OVR",
+	"EQU", "NEQ", "GTH", "LTH", "JMP", "JCN", "JSR", "STH",
+	"LDZ", "STZ", "LDR", "STR", "LDA", "STA", "DEI", "DEO",
+	"ADD", "SUB", "MUL", "DIV", "AND", "ORA", "EOR", "SFT"
+};
+
+/* clang-format on */
+
+static int
+find(char *s, char t)
+{
+	int i = 0;
+	char c;
+	while((c = *s++)) {
+		if(c == t) return i;
+		i++;
+	}
+	return -1;
+}
+
+static int
+shex(char *s)
+{
+	int d, n = 0;
+	char c;
+	while((c = *s++)) {
+		d = find(hexad, c);
+		if(d < 0) return d;
+		n = n << 4, n |= d;
+	}
+	return n;
+}
+
+static int
+scmp(char *a, char *b, int len)
+{
+	int i = 0;
+	while(a[i] == b[i])
+		if(!a[i] || ++i >= len) return 1;
+	return 0;
+}
+
+static char *
+copy(char *src, char *dst, char c)
+{
+	while(*src && *src != c) *dst++ = *src++;
+	*dst++ = 0;
+	return dst;
+}
+
+static char *
+save(char *s, char c)
+{
+	char *o = dictnext;
+	while((*dictnext++ = *s++) && *s);
+	*dictnext++ = c;
+	return o;
+}
+
+static char *
+join(char *a, char j, char *b)
+{
+	char *res = dictnext;
+	save(a, j), save(b, 0);
+	return res;
+}
+
+static char *
+push(char *s, char c)
+{
+	char *d;
+	for(d = dict; d < dictnext; d++) {
+		char *ss = s, *dd = d, a, b;
+		while((a = *dd++) == (b = *ss++))
+			if(!a && !b) return d;
+	}
+	return save(s, c);
+}
+
+static Item *
+finditem(char *name, Item *list, int len)
+{
+	int i;
+	if(name[0] == '&')
+		name = join(scope, '/', name + 1);
+	for(i = 0; i < len; i++)
+		if(scmp(list[i].name, name, 0x40))
+			return &list[i];
+	return NULL;
+}
+
+static Uint8
+findopcode(char *s)
+{
+	int i;
+	for(i = 0; i < 0x20; i++) {
+		int m = 3;
+		if(!scmp(ops[i], s, 3)) continue;
+		if(!i) i |= (1 << 7);
+		while(s[m]) {
+			if(s[m] == '2')
+				i |= (1 << 5);
+			else if(s[m] == 'r')
+				i |= (1 << 6);
+			else if(s[m] == 'k')
+				i |= (1 << 7);
+			else
+				return 0;
+			m++;
+		}
+		return i;
+	}
+	return 0;
+}
+
+static int
+walkcomment(FILE *f, Context *ctx)
+{
+	char c, last = 0;
+	int depth = 1;
+	while(f && fread(&c, 1, 1, f)) {
+		if(c <= 0x20) {
+			if(c == 0xa) ctx->line++;
+			if(last == '(')
+				depth++;
+			else if(last == ')' && --depth < 1)
+				return 1;
+			last = 0;
+		} else if(last <= 0x20)
+			last = c;
+		else
+			last = '~';
+	}
+	return error_asm("Comment incomplete");
+}
+
+static int parse(char *w, FILE *f, Context *ctx);
+
+static int
+walkmacro(Item *m, Context *ctx)
+{
+	unsigned char c;
+	char *dataptr = m->data, *_token = token;
+	while((c = *dataptr++)) {
+		if(c < 0x21) {
+			*_token = 0x00;
+			if(token[0] && !parse(token, NULL, ctx)) return 0;
+			_token = token;
+		} else if(_token - token < 0x2f)
+			*_token++ = c;
+		else
+			return error_asm("Token size exceeded");
+	}
+	return 1;
+}
+
+static int
+walkfile(FILE *f, Context *ctx)
+{
+	unsigned char c;
+	char *_token = token;
+	while(f && fread(&c, 1, 1, f)) {
+		if(c < 0x21) {
+			*_token = 0x00;
+			if(token[0] && !parse(token, f, ctx)) return 0;
+			if(c == 0xa) ctx->line++;
+			_token = token;
+		} else if(_token - token < 0x2f)
+			*_token++ = c;
+		else
+			return error_asm("Token size exceeded");
+	}
+	*_token = 0;
+	return parse(token, f, ctx);
+}
+
+static char *
+makelambda(int id)
+{
+	lambda[0] = (char)0xce;
+	lambda[1] = (char)0xbb;
+	lambda[2] = hexad[id >> 0x4];
+	lambda[3] = hexad[id & 0xf];
+	return lambda;
+}
+
+static int
+makemacro(char *name, FILE *f, Context *ctx)
+{
+	int depth = 0;
+	char c;
+	Item *m;
+	if(macro_len >= 0x100) return error_asm("Macros limit exceeded");
+	if(isinvalid(name)) return error_asm("Macro invalid");
+	if(findmacro(name)) return error_asm("Macro duplicate");
+	if(findlabel(name)) return error_asm("Label duplicate");
+	m = &macros[macro_len++];
+	m->name = push(name, 0);
+	m->data = dictnext;
+	while(f && fread(&c, 1, 1, f) && c != '{')
+		if(c == 0xa) ctx->line++;
+	while(f && fread(&c, 1, 1, f)) {
+		if(c == 0xa) ctx->line++;
+		if(c == '%') return error_asm("Macro nested");
+		if(c == '{') depth++;
+		if(c == '}' && --depth) break;
+		*dictnext++ = c;
+	}
+	*dictnext++ = 0;
+	return 1;
+}
+
+static int
+makelabel(char *name, int setscope, Context *ctx)
+{
+	Item *l;
+	if(name[0] == '&')
+		name = join(scope, '/', name + 1);
+	if(labels_len >= 0x400) return error_asm("Labels limit exceeded");
+	if(isinvalid(name)) return error_asm("Label invalid");
+	if(findmacro(name)) return error_asm("Label duplicate");
+	if(findlabel(name)) return error_asm("Label duplicate");
+	l = &labels[labels_len++];
+	l->name = push(name, 0);
+	l->addr = ptr;
+	l->refs = 0;
+	if(setscope) copy(name, scope, '/');
+	return 1;
+}
+
+static int
+makeref(char *label, char rune, Uint16 addr, Context *ctx)
+{
+	Item *r;
+	if(refs_len >= 0x1000) return error_asm("References limit exceeded");
+	r = &refs[refs_len++];
+	if(label[0] == '{') {
+		lambda_stack[lambda_ptr++] = lambda_len;
+		r->name = push(makelambda(lambda_len++), 0);
+		if(label[1]) return error_asm("Label invalid");
+	} else if(label[0] == '&' || label[0] == '/') {
+		r->name = join(scope, '/', label + 1);
+	} else
+		r->name = push(label, 0);
+	r->rune = rune;
+	r->addr = addr;
+	r->line = ctx->line;
+	r->data = ctx->path;
+	return 1;
+}
+
+static int
+writepad(char *w, Context *ctx)
+{
+	Item *l;
+	int rel = w[0] == '$' ? ptr : 0;
+	if(ishex(w + 1)) {
+		ptr = shex(w + 1) + rel;
+		return 1;
+	}
+	if((l = findlabel(w + 1))) {
+		ptr = l->addr + rel;
+		return 1;
+	}
+	return error_asm("Padding invalid");
+}
+
+static int
+writebyte(Uint8 b, Context *ctx)
+{
+	if(ptr < PAGE)
+		return error_asm("Writing zero-page");
+	else if(ptr >= 0x10000)
+		return error_asm("Writing outside memory");
+	else if(ptr < length)
+		return error_asm("Writing rewind");
+	data[ptr++] = b;
+	if(b)
+		length = ptr;
+	return 1;
+}
+
+static int
+writehex(char *w, Context *ctx)
+{
+	if(*w == '#')
+		writebyte(findopcode("LIT") | !!(++w)[2] << 5, ctx);
+	if(ishex(w)) {
+		if(w[1] && !w[2])
+			return writebyte(shex(w), ctx);
+		else if(w[3] && !w[4])
+			return writeshort(shex(w));
+	}
+	return error_asm("Hexadecimal invalid");
+}
+
+static int
+writestring(char *w, Context *ctx)
+{
+	char c;
+	while((c = *(w++)))
+		if(!writebyte(c, ctx)) return error_asm("String invalid");
+	return 1;
+}
+
+static int
+assemble(char *filename)
+{
+	FILE *f;
+	int res;
+	Context ctx;
+	ctx.line = 1;
+	ctx.path = push(filename, 0);
+	if(!(f = fopen(filename, "r")))
+		return error_top("File missing", filename);
+	res = walkfile(f, &ctx);
+	fclose(f);
+	return res;
+}
+
+static int
+parse(char *w, FILE *f, Context *ctx)
+{
+	Item *m;
+	switch(w[0]) {
+	case 0x0: return 1;
+	case '(':
+		if(w[1] <= 0x20)
+			return walkcomment(f, ctx);
+		else
+			return error_asm("Invalid word");
+	case '%': return makemacro(w + 1, f, ctx);
+	case '@': return makelabel(w + 1, 1, ctx);
+	case '&': return makelabel(w, 0, ctx);
+	case '}': return makelabel(makelambda(lambda_stack[--lambda_ptr]), 0, ctx);
+	case '#': return writehex(w, ctx);
+	case '_': return makeref(w + 1, w[0], ptr, ctx) && writebyte(0xff, ctx);
+	case ',': return makeref(w + 1, w[0], ptr + 1, ctx) && writebyte(findopcode("LIT"), ctx) && writebyte(0xff, ctx);
+	case '-': return makeref(w + 1, w[0], ptr, ctx) && writebyte(0xff, ctx);
+	case '.': return makeref(w + 1, w[0], ptr + 1, ctx) && writebyte(findopcode("LIT"), ctx) && writebyte(0xff, ctx);
+	case ':': printf("Deprecated rune %s, use =%s\n", w, w + 1); /* fall-through */
+	case '=': return makeref(w + 1, w[0], ptr, ctx) && writeshort(0xffff);
+	case ';': return makeref(w + 1, w[0], ptr + 1, ctx) && writebyte(findopcode("LIT2"), ctx) && writeshort(0xffff);
+	case '?': return makeref(w + 1, w[0], ptr + 1, ctx) && writebyte(0x20, ctx) && writeshort(0xffff);
+	case '!': return makeref(w + 1, w[0], ptr + 1, ctx) && writebyte(0x40, ctx) && writeshort(0xffff);
+	case '"': return writestring(w + 1, ctx);
+	case '~': return !assemble(w + 1) ? error_asm("Include missing") : 1;
+	case '$':
+	case '|': return writepad(w, ctx);
+	case '[':
+	case ']': return 1;
+	}
+	if(ishex(w)) return writehex(w, ctx);
+	if(isopc(w)) return writebyte(findopcode(w), ctx);
+	if((m = findmacro(w))) return walkmacro(m, ctx);
+	return makeref(w, ' ', ptr + 1, ctx) && writebyte(0x60, ctx) && writeshort(0xffff);
+}
+
+static int
+resolve(char *filename)
+{
+	int i, rel;
+	if(!length) return error_top("Output empty", filename);
+	for(i = 0; i < refs_len; i++) {
+		Item *r = &refs[i], *l = findlabel(r->name);
+		Uint8 *rom = data + r->addr;
+		if(!l) return error_ref("Label unknown");
+		switch(r->rune) {
+		case '_':
+		case ',':
+			*rom = rel = l->addr - r->addr - 2;
+			if((Sint8)data[r->addr] != rel)
+				return error_ref("Reference too far");
+			break;
+		case '-':
+		case '.':
+			*rom = l->addr;
+			break;
+		case ':':
+		case '=':
+		case ';':
+			*rom++ = l->addr >> 8, *rom = l->addr;
+			break;
+		case '?':
+		case '!':
+		default:
+			rel = l->addr - r->addr - 2;
+			*rom++ = rel >> 8, *rom = rel;
+			break;
+		}
+		l->refs++;
+	}
+	return 1;
+}
+
+static int
+build(char *rompath)
+{
+	int i;
+	FILE *dst, *dstsym;
+	char *sympath = join(rompath, '.', "sym");
+	/* rom */
+	if(!(dst = fopen(rompath, "wb")))
+		return !error_top("Output file invalid", rompath);
+	for(i = 0; i < labels_len; i++)
+		if(!labels[i].refs && (unsigned char)(labels[i].name[0] - 'A') > 25)
+			printf("-- Unused label: %s\n", labels[i].name);
+	fwrite(data + PAGE, length - PAGE, 1, dst);
+	printf(
+		"Assembled %s in %d bytes(%.2f%% used), %d labels, %d macros.\n",
+		rompath,
+		length - PAGE,
+		(length - PAGE) / 652.80,
+		labels_len,
+		macro_len);
+	/* sym */
+	if(!(dstsym = fopen(sympath, "wb")))
+		return !error_top("Symbols file invalid", sympath);
+	for(i = 0; i < labels_len; i++) {
+		Uint8 hb = labels[i].addr >> 8, lb = labels[i].addr;
+		char c, d = 0, *name = labels[i].name;
+		fwrite(&hb, 1, 1, dstsym);
+		fwrite(&lb, 1, 1, dstsym);
+		while((c = *name++)) fwrite(&c, 1, 1, dstsym);
+		fwrite(&d, 1, 1, dstsym);
+	}
+	fclose(dst), fclose(dstsym);
+	return 1;
+}
+
+int
+main(int argc, char *argv[])
+{
+	ptr = PAGE;
+	copy("on-reset", scope, 0);
+	if(argc == 2 && scmp(argv[1], "-v", 2)) return !printf("Uxnasm - Uxntal Assembler, 15 Jan 2025.\n");
+	if(argc != 3) return error_top("usage", "uxnasm [-v] input.tal output.rom");
+	return !assemble(argv[1]) || !resolve(argv[2]) || !build(argv[2]);
+}