Reorganized

platform_linux.c

@@ -0,0 +1,114 @@
+#include "forth.h"
+#include <stdarg.h>
+
+static inline long syscall3(long n, long a1, long a2, long a3) {
+    long ret;
+    __asm__ volatile ("syscall"
+        : "=a"(ret)
+        : "a"(n), "D"(a1), "S"(a2), "d"(a3)
+        : "rcx", "r11", "memory");
+    return ret;
+}
+
+static inline long syscall1(long n, long a1) {
+    long ret;
+    __asm__ volatile ("syscall"
+        : "=a"(ret)
+        : "a"(n), "D"(a1)
+        : "rcx", "r11", "memory");
+    return ret;
+}
+
+void forth_putchar(char c) {
+    char ch = c;
+    syscall3(1, 1, (long)&ch, 1);
+}
+
+void forth_fflush(void) {
+}
+
+int forth_getchar(void) {
+    unsigned char c;
+    long n = syscall3(0, 0, (long)&c, 1);
+    if (n <= 0) return FORTH_EOF;
+    return (int)c;
+}
+
+void forth_panic(void) {
+    syscall1(60, 1);
+    __builtin_unreachable();
+}
+
+int64_t forth_strtoll(const char* str, char** endptr, int base) {
+    const char* s = str;
+    int neg = 0;
+    int64_t val = 0;
+    while (forth_isspace(*s)) s++;
+    if (*s == '-') { neg = 1; s++; }
+    else if (*s == '+') { s++; }
+    while (*s >= '0' && *s <= '9') {
+        val = val * base + (*s - '0');
+        s++;
+    }
+    if (endptr) *endptr = (char*)s;
+    return neg ? -val : val;
+}
+
+static void print_str(const char* s) {
+    while (*s) forth_putchar(*s++);
+}
+
+static void print_int(long long v) {
+    char buf[32];
+    int i = 30;
+    int neg = 0;
+    if (v < 0) { neg = 1; v = -v; }
+    buf[31] = '\0';
+    if (v == 0) {
+        buf[i--] = '0';
+    } else {
+        while (v > 0 && i >= 0) {
+            buf[i--] = '0' + (v % 10);
+            v /= 10;
+        }
+    }
+    if (neg) buf[i--] = '-';
+    print_str(&buf[i + 1]);
+}
+
+void forth_printf(const char* fmt, ...) {
+    va_list ap;
+    va_start(ap, fmt);
+    while (*fmt) {
+        if (*fmt == '%' && *(fmt + 1)) {
+            fmt++;
+            if (*fmt == 's') {
+                print_str(va_arg(ap, const char*));
+            } else if (*fmt == 'c') {
+                forth_putchar((char)va_arg(ap, int));
+            } else if (*fmt == '%') {
+                forth_putchar('%');
+            } else if (*fmt == 'l') {
+                if (*(fmt + 1) == 'l' && (*(fmt + 2) == 'd' || *(fmt + 2) == 'i' || *(fmt + 2) == 'u')) {
+                    fmt += 2;
+                    print_int(va_arg(ap, long long));
+                }
+            } else if (*fmt == 'd' || *fmt == 'i' || *fmt == 'u') {
+                print_int(va_arg(ap, int));
+            } else {
+                forth_putchar('%');
+                forth_putchar(*fmt);
+            }
+        } else {
+            forth_putchar(*fmt);
+        }
+        fmt++;
+    }
+    va_end(ap);
+}
+
+void _start(void) {
+    forth_run();
+    syscall1(60, 0);
+    __builtin_unreachable();
+}