This code is gated behind the CHAINLOADING define. To build a
release-style m1n1 with chainloading for use with the installer
or kmutil, use:
make CHAINLOADING=1 RELEASE=1
To tell m1n1 to chainload another binary, use this var payload:
chainload=<ESP partition UUID>;<file path>
e.g.
chainload=a17b7e46-e950-bb4f-bc82-8ab1047a058e;m1n1/m1n1.bin
Closes: #154
Co-authored-by: Finn Behrens <me@kloenk.dev>
Co-authored-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Hector Martin <marcan@marcan.st>
iBoot does this for us, but this is for the benefit of chainload.py and
other dump loaders that may not.
Signed-off-by: Hector Martin <marcan@marcan.st>
heapblock is a simple `sbrk` style implementation, also useful as an
"endless" decompression buffer. dlmalloc is used on top as a malloc
implementation.
This also changes how the Python side manages its heap. We still use a
python-side malloc implementation (since this is faster), and we put the
Python heap at the m1n1 heap + 128MB, without allocating it.
Hopefully this should never step on anything m1n1 neads, and avoids
having to manage freeing across Python script calls.
Signed-off-by: Hector Martin <marcan@marcan.st>
So it turns out iBoot is happy to load mach-o files with a section hanging
"off the end" of the file (it does not over-read, it just ignores the
excess). We can use this to our advantage to support appending payloads
to m1n1 with a simple `cat`.
Signed-off-by: Hector Martin <marcan@marcan.st>
