Add support for Docker image for building

Dockerfile

@@ -0,0 +1,24 @@
+# Set up build stage 
+FROM ubuntu:18.04 AS buildstage
+ENV DEBIAN_FRONTEND=noninteractive TZ=Europe/Amsterdam
+
+RUN dpkg --add-architecture i386
+
+RUN apt-get update && \
+    apt-get -y install zip wget git build-essential make \
+    libc6:i386 libncurses5:i386 libstdc++6:i386 
+
+ENV ROOTDIR=/pocketbook-jailbreak
+WORKDIR ${ROOTDIR}
+
+RUN wget https://toolchains.bootlin.com/downloads/releases/toolchains/armv7-eabihf/tarballs/armv7-eabihf--musl--stable-2018.11-1.tar.bz2
+RUN tar -xvf armv7-eabihf--musl--stable-2018.11-1.tar.bz2
+
+RUN wget https://github.com/ezdiy/pocketbook-sdk5/archive/master.tar.gz
+RUN tar -xvf master.tar.gz
+
+ENV PATH="${ROOTDIR}/pocketbook-sdk5-master/bin:${ROOTDIR}/armv7-eabihf--musl--stable-2018.11-1/bin:${PATH}"
+
+WORKDIR /pbjb
+
+CMD make

README.md

@@ -2,11 +2,37 @@ Use https://www.mobileread.com/forums/showthread.php?p=3921722 if you have an is
 
 по русски: http://4pda.ru/forum/index.php?s=&showtopic=886480&view=findpost&p=92768601
 
-This tree uses both Pocketbook SDK for dynamic linking, as well as static musl libc cross comppiler
+This tree uses both Pocketbook SDK for dynamic linking, as well as static musl libc cross compiler
 for critical services (ssh and smb). The SDK has poor portability between firmware versions, but allows
 for using ncurses or openssl (those are not suitable for static linking).
 
-For static musl cross compier: https://toolchains.bootlin.com/downloads/releases/toolchains/armv7-eabihf/tarballs/armv7-eabihf--musl--stable-2018.11-1.tar.bz2
+For static musl cross compiler: https://toolchains.bootlin.com/downloads/releases/toolchains/armv7-eabihf/tarballs/armv7-eabihf--musl--stable-2018.11-1.tar.bz2
 For SDK cross compiler: https://github.com/ezdiy/pocketbook-sdk5/archive/master.tar.gz
 
 Unpack, and point your $PATH to 'bin' folder in both SDKs (gcc are differentiated by cross prefix, cc and cc5 in makefile).
+
+Alternatively you can use a Docker image for compiling and linking, it contains the necessary (i386) packages and the above compilers/toolchains.
+
+Requirements: [installed Docker environment](https://docs.docker.com/get-docker) 
+
+To prepare the Docker image, clone this repository with its submodule(s), if you haven't yet:
+
+```console
+git clone https://github.com/ezdiy/pbjb.git --recurse-submodules
+```
+
+build the image:
+```console
+cd pbjb
+docker build -t pbjb .
+```
+
+To build pbjb, run the image (from within the same pbjb directory), this runs 'make':
+```console
+./rundocker.sh
+```
+
+You can also specify a command to run, e.g. to run a 'make clean':
+```console
+./rundocker.sh make clean
+```

rundocker.sh

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+#!/bin/bash
+docker run --rm -it --volume=$(pwd):/pbjb pbjb "$@"