From 0916287b79914bceacecb7d05b5ed2bd065a4869 Mon Sep 17 00:00:00 2001
From: satmandu <satadru@umich.edu>
Date: Fri, 13 Dec 2019 10:19:41 -0500
Subject: [PATCH] Allow user to skip updating VideoCore libraries (#292)

* Allow user to skip updating VideoCore libraries

Users who are running non-raspbian distributions, especially on other architectures
like arm64, may already have videocore libraries and applications compiled for arm64.
These will get overwritten unless updating the VideoCore libraries is skipped.

This implements a SKIP_VCLIBS option to allow that step to be skipped, which may be
used alongside the SKIP_SDK option. This is also referred to in a suggestion for a
SKIP_USERLAND option here: https://github.com/Hexxeh/rpi-update/pull/221#issuecomment-243559009

Signed-off-by: Satadru Pramanik <satadru@umich.edu>
---
 README.md  | 8 ++++++++
 rpi-update | 8 +++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 7a1ddc0..b41dd9f 100644
--- a/README.md
+++ b/README.md
@@ -96,6 +96,14 @@ Avoids making backup of /boot and /lib/modules on first run.
 By default the downloaded files (/root/.rpi-firmware) are deleted at end of update.
 Use this option to keep the files.
 
+#### `SKIP_VCLIBS`
+
+    sudo SKIP_VCLIBS=1 rpi-update
+
+Will update everything **except** the VideoCore libraries.
+Use this option to keep the existing VideoCore libraries if you do not want your
+local versions overwritten.
+
 #### `ROOT_PATH` and `BOOT_PATH`
 
     sudo ROOT_PATH=/media/root BOOT_PATH=/media/boot rpi-update
diff --git a/rpi-update b/rpi-update
index 08f7268..83812e6 100755
--- a/rpi-update
+++ b/rpi-update
@@ -30,6 +30,7 @@ BOOT_PATH=${BOOT_PATH:-"/boot"}
 WORK_PATH=${WORK_PATH:-"${ROOT_PATH}/root"}
 SKIP_KERNEL=${SKIP_KERNEL:-0}
 SKIP_SDK=${SKIP_SDK:-0}
+SKIP_VCLIBS=${SKIP_VCLIBS:-0}
 SKIP_REPODELETE=${SKIP_REPODELETE:-0}
 SKIP_BACKUP=${SKIP_BACKUP:-0}
 SKIP_DOWNLOAD=${SKIP_DOWNLOAD:-0}
@@ -151,7 +152,12 @@ function update_modules {
 }
 
 function update_vc_libs {
-	echo " *** Updating VideoCore libraries"
+	if [[ ${SKIP_VCLIBS} -eq 0 ]]; then
+		echo " *** Updating VideoCore libraries"
+	else
+		echo " *** As requested, not updating VideoCore libraries"
+		return
+	fi
 
 	if [[ -e ${ROOT_PATH}/bin/sh ]]; then
 		local ELFOUTPUT=$(readelf -a "${ROOT_PATH}/bin/sh"; readelf -h "${ROOT_PATH}/bin/sh")