--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rvinterf/g23sh/usercmd.c	Tue Apr 22 07:21:04 2014 +0000
@@ -0,0 +1,90 @@
+/*
+ * This module implements g23sh user command dispatch.
+ */
+
+#include <sys/types.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+#include <strings.h>
+#include <stdlib.h>
+
+extern char usercmd[];
+
+extern void cmd_sendsp();
+
+void
+cmd_exit()
+{
+	tty_cleanup();
+	exit(0);
+}
+
+static struct cmdtab {
+	char *cmd;
+	int minargs;
+	int maxargs;
+	void (*func)();
+} cmdtab[] = {
+	{"exit", 0, 0, cmd_exit},
+	{"quit", 0, 0, cmd_exit},
+	{"sp", 2, 2, cmd_sendsp},
+	{0, 0, 0, 0}
+};
+
+void
+dispatch_user_cmd()
+{
+	char *argv[10];
+	char *cp, **ap;
+	struct cmdtab *tp;
+
+	for (cp = usercmd; isspace(*cp); cp++)
+		;
+	if (!*cp || *cp == '#')
+		return;
+	argv[0] = cp;
+	while (*cp && !isspace(*cp))
+		cp++;
+	if (*cp)
+		*cp++ = '\0';
+	for (tp = cmdtab; tp->cmd; tp++)
+		if (!strcmp(tp->cmd, argv[0]))
+			break;
+	if (!tp->func) {
+		printf("error: no such command\n");
+		return;
+	}
+	for (ap = argv + 1; ; ) {
+		while (isspace(*cp))
+			cp++;
+		if (!*cp || *cp == '#')
+			break;
+		if (ap - argv - 1 >= tp->maxargs) {
+			printf("error: too many arguments\n");
+			return;
+		}
+		if (*cp == '"') {
+			*ap++ = ++cp;
+			while (*cp && *cp != '"')
+				cp++;
+			if (*cp != '"') {
+				printf("error: unterminated quoted string\n");
+				return;
+			}
+			*cp++ = '\0';
+		} else {
+			*ap++ = cp;
+			while (*cp && !isspace(*cp))
+				cp++;
+			if (*cp)
+				*cp++ = '\0';
+		}
+	}
+	if (ap - argv - 1 < tp->minargs) {
+		printf("error: too few arguments\n");
+		return;
+	}
+	*ap = 0;
+	tp->func(ap - argv, argv);
+}