From e95614755b583b77d26300d32475d2e385c09b94 Mon Sep 17 00:00:00 2001
From: Virgil Dupras <hsoft@hardcoded.net>
Date: Mon, 9 Mar 2020 22:26:02 -0400
Subject: [PATCH] emul: add forth target

---
 emul/.gitignore     |  4 +--
 emul/Makefile       | 13 +++++++--
 emul/forth/forth.c  | 68 +++++++++++++++++++++++++++++++++++++++++++++
 emul/forth/glue.asm | 40 ++++++++++++++++++++++++++
 4 files changed, 120 insertions(+), 5 deletions(-)
 create mode 100644 emul/forth/forth.c
 create mode 100644 emul/forth/glue.asm

diff --git a/emul/.gitignore b/emul/.gitignore
index 9ee7d93..c099a28 100644
--- a/emul/.gitignore
+++ b/emul/.gitignore
@@ -1,5 +1,5 @@
 /shell/shell
-/bshell/shell
+/forth/forth
 /zasm/zasm
 /zasm/avra
 /runbin/runbin
@@ -7,6 +7,4 @@
 /*/*.bin
 /cfsin/zasm
 /cfsin/ed
-/cfsin/basic
-/cfsin/forth
 /cfsin/user.h
diff --git a/emul/Makefile b/emul/Makefile
index 5cd6d13..3bd7dde 100644
--- a/emul/Makefile
+++ b/emul/Makefile
@@ -1,10 +1,10 @@
 CFSPACK_OBJ = ../tools/cfspack/libcfs.o
-TARGETS = shell/shell zasm/zasm runbin/runbin
+TARGETS = shell/shell zasm/zasm runbin/runbin forth/forth
 KERNEL = ../kernel
 APPS = ../apps
 ZASMBIN = zasm/zasm
 AVRABIN = zasm/avra
-SHELLAPPS = zasm ed forth
+SHELLAPPS = zasm ed
 SHELLTGTS = ${SHELLAPPS:%=cfsin/%}
 CFSIN_CONTENTS = $(SHELLTGTS) cfsin/user.h
 OBJS = emul.o libz80/libz80.o
@@ -24,6 +24,15 @@ shell/shell-bin.h: shell/shell.bin
 shell/shell: shell/shell.c $(SHELLOBJS) shell/shell-bin.h 
 	$(CC) shell/shell.c $(SHELLOBJS) -o $@
 
+forth/forth.bin: forth/glue.asm $(ZASMBIN)
+	$(ZASMBIN) $(KERNEL) $(APPS) < forth/glue.asm | tee $@ > /dev/null
+
+forth/forth-bin.h: forth/forth.bin
+	./bin2c.sh KERNEL < forth/forth.bin | tee $@ > /dev/null
+
+forth/forth: forth/forth.c $(OBJS) forth/forth-bin.h 
+	$(CC) forth/forth.c $(OBJS) -o $@
+
 zasm/kernel-bin.h: zasm/kernel.bin
 	./bin2c.sh KERNEL < zasm/kernel.bin | tee $@ > /dev/null
 
diff --git a/emul/forth/forth.c b/emul/forth/forth.c
new file mode 100644
index 0000000..1848772
--- /dev/null
+++ b/emul/forth/forth.c
@@ -0,0 +1,68 @@
+#include <stdint.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <termios.h>
+#include "../emul.h"
+#include "forth-bin.h"
+
+// in sync with glue.asm
+#define RAMSTART 0x2000
+#define STDIO_PORT 0x00
+
+static int running;
+
+static uint8_t iord_stdio()
+{
+    int c = getchar();
+    if (c == EOF) {
+        running = 0;
+    }
+    return (uint8_t)c;
+}
+
+static void iowr_stdio(uint8_t val)
+{
+    if (val == 0x04) { // CTRL+D
+        running = 0;
+    } else {
+        putchar(val);
+    }
+}
+
+int main(int argc, char *argv[])
+{
+    bool tty = isatty(fileno(stdin));
+    struct termios termInfo;
+    if (tty) {
+        // Turn echo off: the shell takes care of its own echoing.
+        if (tcgetattr(0, &termInfo) == -1) {
+            printf("Can't setup terminal.\n");
+            return 1;
+        }
+        termInfo.c_lflag &= ~ECHO;
+        termInfo.c_lflag &= ~ICANON;
+        tcsetattr(0, TCSAFLUSH, &termInfo);
+    }
+
+    Machine *m = emul_init();
+    m->ramstart = RAMSTART;
+    m->iord[STDIO_PORT] = iord_stdio;
+    m->iowr[STDIO_PORT] = iowr_stdio;
+    // initialize memory
+    for (int i=0; i<sizeof(KERNEL); i++) {
+        m->mem[i] = KERNEL[i];
+    }
+    // Run!
+    running = 1;
+
+    while (running && emul_step());
+
+    if (tty) {
+        printf("Done!\n");
+        termInfo.c_lflag |= ECHO;
+        termInfo.c_lflag |= ICANON;
+        tcsetattr(0, TCSAFLUSH, &termInfo);
+        emul_printdebug();
+    }
+    return 0;
+}
diff --git a/emul/forth/glue.asm b/emul/forth/glue.asm
new file mode 100644
index 0000000..d46846d
--- /dev/null
+++ b/emul/forth/glue.asm
@@ -0,0 +1,40 @@
+.inc "ascii.h"
+.equ	RAMSTART	0x2000
+.equ	STDIO_PORT	0x00
+
+	jp	init
+
+.inc "core.asm"
+.inc "str.asm"
+
+.equ	STDIO_RAMSTART	RAMSTART
+.equ	STDIO_GETC	emulGetC
+.equ	STDIO_PUTC	emulPutC
+.inc "stdio.asm"
+
+.inc "lib/util.asm"
+.inc "lib/parse.asm"
+.inc "lib/ari.asm"
+.inc "lib/fmt.asm"
+.equ FORTH_RAMSTART STDIO_RAMEND
+.inc "forth/main.asm"
+.inc "forth/util.asm"
+.inc "forth/stack.asm"
+.inc "forth/dict.asm"
+
+init:
+	di
+	; setup stack
+	ld	sp, 0xffff
+	call	forthMain
+	halt
+
+emulGetC:
+	; Blocks until a char is returned
+	in	a, (STDIO_PORT)
+	cp	a		; ensure Z
+	ret
+
+emulPutC:
+	out	(STDIO_PORT), a
+	ret