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/writesubfont.c

@@ -0,0 +1,54 @@
+/*
+ * 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>
+
+static
+void
+packinfo(Fontchar *fc, uint8_t *p, int n)
+{
+	int j;
+
+	for(j=0;  j<=n;  j++){
+		p[0] = fc->x;
+		p[1] = fc->x>>8;
+		p[2] = fc->top;
+		p[3] = fc->bottom;
+		p[4] = fc->left;
+		p[5] = fc->width;
+		fc++;
+		p += 6;
+	}
+}
+
+int
+writesubfont(int fd, Subfont *f)
+{
+	char hdr[3*12+1];
+	uint8_t *data;
+	int nb;
+
+	sprint(hdr, "%11d %11d %11d ", f->n, f->height, f->ascent);
+	if(write(fd, hdr, 3*12) != 3*12){
+   Err:
+		werrstr("writesubfont: bad write: %r");
+		return -1;
+	}
+	nb = 6*(f->n+1);
+	data = malloc(nb);
+	if(data == nil)
+		return -1;
+	packinfo(f->info, data, f->n);
+	if(write(fd, data, nb) != nb)
+		goto Err;
+	free(data);
+	return 0;
+}