first usable version of kernel and commands

After an year of hard work, this is a first "usable" version of Jehanne.

sys/src/lib/draw/subfontcache.c

@@ -0,0 +1,49 @@
+/*
+ * This file is part of the UCB release of Plan 9. It is subject to the license
+ * terms in the LICENSE file found in the top-level directory of this
+ * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
+ * part of the UCB release of Plan 9, including this file, may be copied,
+ * modified, propagated, or distributed except according to the terms contained
+ * in the LICENSE file.
+ */
+
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+
+/*
+ * Easy versions of the cache routines; may be substituted by fancier ones for other purposes
+ */
+
+static char	*lastname;
+Subfont	*lastsubfont;
+
+Subfont*
+lookupsubfont(Display *d, char *name)
+{
+	if(d && strcmp(name, "*default*") == 0)
+		return d->defaultsubfont;
+	if(lastname && strcmp(name, lastname)==0)
+	if(d==lastsubfont->bits->display){
+		lastsubfont->ref++;
+		return lastsubfont;
+	}
+	return 0;
+}
+
+void
+installsubfont(char *name, Subfont *subfont)
+{
+	free(lastname);
+	lastname = strdup(name);
+	lastsubfont = subfont;	/* notice we don't free the old one; that's your business */
+}
+
+void
+uninstallsubfont(Subfont *subfont)
+{
+	if(subfont == lastsubfont){
+		lastname = 0;
+		lastsubfont = 0;
+	}
+}