big-img, chainload self

grub/Makefile

@@ -0,0 +1,13 @@
+.POSIX:
+
+.PHONY: clean run
+
+main.img:
+	make -C '../mbrs' && cp '../bios_hello_world.img.sym' 'iso/boot/main.img'
+	grub-mkrescue -o '$@' iso
+
+clean:
+	rm -f iso/boot/*.img *.img
+
+run: main.img
+	qemu-system-i386 -hda '$<'

grub/chainloader/README.md

@@ -11,3 +11,5 @@ This example uses a file, but the most common way to use it is with:
     chainloader +1
 
 which uses the first sector of some partition instead of a file.
+
+TODO: why does it fail for hybrid ISO images? <http://superuser.com/questions/154134/grub-how-to-boot-into-iso-partition#comment1337357_154271>

grub/chainloader/iso/boot/grub/grub.cfg

@@ -1,5 +1,7 @@
-set timeout=0
-set default="0"
-menuentry "main" {
+menuentry "hello-world" {
     chainloader /boot/main.img
 }
+# Reload ourselves again.
+menuentry "self +1" {
+    chainloader +1
+}