Merge branch 'devcontainer' into development

.devcontainer/Dockerfile

@@ -0,0 +1,50 @@
+#-------------------------------------------------------------------------------------------------------------
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License. See https://go.microsoft.com/fwlink/?linkid=2090316 for license information.
+#-------------------------------------------------------------------------------------------------------------
+
+FROM debian:9
+
+# Avoid warnings by switching to noninteractive
+ENV DEBIAN_FRONTEND=noninteractive
+
+# This Dockerfile adds a non-root 'vscode' user with sudo access. However, for Linux,
+# this user's GID/UID must match your local user UID/GID to avoid permission issues
+# with bind mounts. Update USER_UID / USER_GID if yours is not 1000. See
+# https://aka.ms/vscode-remote/containers/non-root-user for details.
+ARG USERNAME=vscode
+ARG USER_UID=1000
+ARG USER_GID=$USER_UID
+
+# Configure apt and install packages
+RUN apt-get update \
+    && apt-get -y install --no-install-recommends apt-utils dialog 2>&1 \
+    # 
+    # Verify git, process tools, lsb-release (useful for CLI installs) installed
+    && apt-get -y install git iproute2 procps lsb-release \
+    #
+    # Install C++ tools
+    && apt-get -y install build-essential cppcheck valgrind \
+    #
+    ## Install newer version of CMake (OpenJPH requires 3.10+, debian has older version)
+    && apt-get install wget \
+    && wget https://github.com/Kitware/CMake/releases/download/v3.15.2/cmake-3.15.2.tar.gz \
+    && tar -zxvf cmake-3.15.2.tar.gz \
+    && (cd /cmake-3.15.2; ./bootstrap; make -j2 install)\
+    && rm -rf /cmake-3.15.2\
+    #
+    # Create a non-root user to use if preferred - see https://aka.ms/vscode-remote/containers/non-root-user.
+    && groupadd --gid $USER_GID $USERNAME \
+    && useradd -s /bin/bash --uid $USER_UID --gid $USER_GID -m $USERNAME \
+    # [Optional] Add sudo support for the non-root user
+    && apt-get install -y sudo \
+    && echo $USERNAME ALL=\(root\) NOPASSWD:ALL > /etc/sudoers.d/$USERNAME\
+    && chmod 0440 /etc/sudoers.d/$USERNAME \
+    #
+    # Clean up
+    && apt-get autoremove -y \
+    && apt-get clean -y \
+    && rm -rf /var/lib/apt/lists/*
+
+# Switch back to dialog for any ad-hoc use of apt-get
+ENV DEBIAN_FRONTEND=

.devcontainer/devcontainer.json

@@ -0,0 +1,31 @@
+// For format details, see https://aka.ms/vscode-remote/devcontainer.json or the definition README at
+// https://github.com/microsoft/vscode-dev-containers/tree/master/containers/cpp
+{
+	"name": "C++",
+	"dockerFile": "Dockerfile",
+	"runArgs": [
+		// Uncomment the next line to use a non-root user. On Linux, this will prevent
+		// new files getting created as root, but you may need to update the USER_UID
+		// and USER_GID in .devcontainer/Dockerfile to match your user if not 1000.
+		// "-u", "vscode",
+
+		"--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined"
+	],
+
+	// Use 'settings' to set *default* container specific settings.json values on container create. 
+	// You can edit these settings after create using File > Preferences > Settings > Remote.
+	"settings": { 
+		"terminal.integrated.shell.linux": "/bin/bash"
+	},
+
+	// Uncomment the next line if you want to publish any ports.
+	// "appPort": [],
+
+	// Uncomment the next line to run commands after the container is created.
+	// "postCreateCommand": "gcc -v",
+
+	// Add the IDs of extensions you want installed when the container is created in the array below.
+	"extensions": [
+		"ms-vscode.cpptools"
+	]
+}

README.md

@@ -16,7 +16,8 @@ The provided command line tools ojph\_compress and ojph\_expand accepts and gene
 
 # Compiling #
 
-The code employs the *cmake* tool to generate a variety of build enviroments.
+The code employs the *cmake* tool to generate a variety of build enviroments.  A visual studio code container is included for building using
+the visual studio code remote conatiners add in (highly recommended)
 
 **For Linux**
 
@@ -47,16 +48,14 @@ The generated library and executables will be in the bin folder.
 
 The library can now be compiled to javascript/wasm.  For this purpose, a small wrapper file (ojph_wrapper.cpp) has been written to interface between javascript and C++; the wrapper currently supports decoding only.  A small demo page demonstrating the script can be accessed [here](https://openjph.org/javascript/demo.html).
 
-Compilation needs the [emscripten](https://emscripten.org/) tools.  The tools are activated using
-```bash 
-emsdk_env.sh
-```
-Then, the javascript decoder can be compiled using
+Compilation needs the [emscripten](https://emscripten.org/) tools. The script subprojects/js/emscripten-docker.sh will create a shell in a docker image
+with emscripten already installed if you don't want to install it locally.  The javascript decoder can be compiled using
 ```bash
 cd subprojects/js/build
 emmake cmake ..
 make
 ```
+
 This creates libopenjph.js and libopenjph.wasm in subprojects/js/html folder.  That html folder also has the demo webpage index.html and a compressed image test.j2c which the script in index.html decodes.  To run the demo webpage on your machine, you need a webserver running on the machine -- Due to security reasons, javascript engines running in a browser cannot access local files on the machine.  A simple python webserver can be run 
 ```python
 python -m SimpleHTTPServer 8000

subprojects/js/emscripten-docker.sh

@@ -0,0 +1,2 @@
+#!/bin/bash
+docker run -it --user $(id -u):$(id -g) -v "$(cd ../.. && pwd)":/src trzeci/emscripten /bin/bash