start 04

1 files changed, 95 insertions, 0 deletions

diff --git a/04b/in04 b/04b/in04
new file mode 100644
index 0000000..1b362ad
--- /dev/null
+++ b/04b/in04
@@ -0,0 +1,95 @@
+// types: char, uchar, short, ushort, int, uint, long, ulong, *type
+// declaration:
+//     static <type> <name>;
+//     local  <type> <name>;
+//     :<label>
+// statement:
+//     <declaration>
+//     if <term> <==/</>/>=/<=/!=> <term> goto <label>
+//     goto <label>
+//     <lvalue> = <rvalue>
+//     <lvalue> += <rvalue>
+//     <lvalue> -= <rvalue>
+//     <function>(<term>, <term>, ...)
+//     syscall(<term>, <term>, ...)
+//     return <rvalue>;
+// term:
+//     <var>
+//     <number>
+// number:
+//     'c
+//     12345
+//     0xabc
+// lvalue:
+//     <var>
+//     *<var>
+//     <var>[<term>]
+// rvalue:
+//     `<string>`
+//     <var>
+//     &<var>
+//     *<var>
+//     <var>[<term>]
+//     ~<var>
+//     <function>(<term>, <term>, ...)
+//     syscall(<term>, <term>, ...)
+//     <term> + <term>
+//     <term> - <term>
+//     <term> * <term>
+//     <term> / <term>
+//     <term> % <term>
+//     <term> & <term>
+//     <term> | <term>
+//     <term> ^ <term>
+//     <term> < <term>  (left shift)
+//     <term> > <term>  (right shift)
+//    (<term> ] <term>)
+
+main();
+
+static char x;
+static uchar y;
+static long z;
+
+function strlen(*char s)
+	local ulong len;
+	local char c;
+	len = 0;
+	:strlen.loop
+	c = s[len];
+	if c == 0 goto strlen.loop_end;
+	len += 1;
+	goto strlen.loop
+	:strlen.loop_end
+	return len;
+
+function putc(char c)
+	local char *p;
+	p = &c;
+	syscall(1, 1, p, 1, 0, 0, 0, 0);
+	return;
+	
+function puts(*char s)
+	local ulong len;
+	len = strlen(s);
+	syscall(1, 1, s, len, 0, 0, 0, 0);
+	return;
+
+function main()
+	local *char hello;
+	hello = `Hello, world!
+`;
+	puts(hello);
+	syscall(0x3c, 0, 0, 0, 0, 0, 0, 0);
+
+function f(*long x, **long y)
+	local long v;
+	local *long p;
+	v = *x;
+	p = *y;
+	*p = v;
+	if v == 0 goto something;
+	p[1] = v + 1;
+	return p[2];
+	:something
+	return p[1];