From 8d4767db5045e9bb1f482579e6de95b01aad89b9 Mon Sep 17 00:00:00 2001
From: chrysn <chrysn@fsfe.org>
Date: Fri, 2 Apr 2021 20:15:21 +0200
Subject: [PATCH] riotbuild: Install Rust

The c2rust program (required in addition to Rust itself) is installed
for what is for most intents and purposes a third party container, but
happens to have its sources shipped along the other containers.
---
 .github/workflows/build.yml |  1 +
 c2rust-built/Dockerfile     | 11 +++++++++++
 c2rust-built/README.md      | 15 +++++++++++++++
 riotbuild/Dockerfile        | 34 +++++++++++++++++++++++++++++++++-
 4 files changed, 60 insertions(+), 1 deletion(-)
 create mode 100644 c2rust-built/Dockerfile
 create mode 100644 c2rust-built/README.md

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index a5c7ecc2..d56592c9 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -29,6 +29,7 @@ on:
   pull_request:
     branches:
       - '*'
+
 jobs:
   build-test:
     name: Build and Test
diff --git a/c2rust-built/Dockerfile b/c2rust-built/Dockerfile
new file mode 100644
index 00000000..14425746
--- /dev/null
+++ b/c2rust-built/Dockerfile
@@ -0,0 +1,11 @@
+FROM immunant/c2rust:ubuntu-bionic-latest as c2rust
+
+# --locked --git --branch ignores --locked; new (2021-03-something) cargo
+# versions behave properly, but C2Rust is on a 2019-12-05 toolchain.
+#
+# Cleaning up cargo home again as set by C2Rust image (that's what contributes
+# most to the delta between the immunant container and this one).
+RUN git clone --recursive https://github.com/chrysn-pull-requests/c2rust -b for-riot && \
+    cargo install --locked --root /usr --path c2rust/c2rust && \
+    rm -rf c2rust && \
+    rm -rf ${CARGO_HOME}
diff --git a/c2rust-built/README.md b/c2rust-built/README.md
new file mode 100644
index 00000000..27d48ded
--- /dev/null
+++ b/c2rust-built/README.md
@@ -0,0 +1,15 @@
+This image contains built and usable versions of [c2rust].
+It is provided because upstream [does not release binaries] for c2rust and its companion tools,
+and because the [branch this is built from (for-riot)] contains some fixes to c2rust required to work on RIOT.
+
+As this changes rarely,
+and because on the github-workers infrastructure this is [difficult to get right],
+this is not built and used through CI yet,
+but manually built an published as:
+
+    docker build . -t chrysn/c2rust-built
+
+[c2rust]: https://github.com/immunant/c2rust
+[does not release binaries]: https://github.com/immunant/c2rust/issues/326
+[branch this is built from (for-riot)]: https://github.com/chrysn-pull-requests/c2rust/tree/for-riot
+[difficult to get right]: https://github.com/RIOT-OS/riotdocker/pull/141
diff --git a/riotbuild/Dockerfile b/riotbuild/Dockerfile
index 01541add..4995b5e2 100644
--- a/riotbuild/Dockerfile
+++ b/riotbuild/Dockerfile
@@ -91,7 +91,11 @@ RUN \
         clang-tools-${LLVM_VERSION}/bionic-updates \
         llvm \
         clang \
-        clang-tools && \
+        clang-tools \
+    && echo 'Installing LLVM version needed by the C2Rust binaries' >&2 && \
+    apt-get -y --no-install-recommends install \
+        llvm-7-dev \
+        && \
     SYMS=$(find /usr/bin -type l) && \
     for file in ${SYMS}; do \
         SYMTARGET=$(readlink -f ${file}) && \
@@ -258,6 +262,31 @@ RUN echo 'Installing python3 packages' >&2 \
     && pip3 install --no-cache-dir -r /tmp/requirements.txt \
     && rm /tmp/requirements.txt
 
+# While sourcing ~/.cargo/env later would have the right short-term effect,
+# we'd still need to set the right path even later when HOME is
+# /data/riotbuild -- so setting it right away.
+ENV PATH ${PATH}:/opt/rustup/.cargo/bin
+# Install nightly Rust via rustup; this is needed for Rust-on-RIOT builds and
+# contains all CARGO_TARGETs currently recognized for RIOT targets.
+#
+# *_HOMEs moved to /opt to make them world readable. RUSTUP_HOME is set
+# persistently in case someone in their image wants to do a quick `sudo rustup
+# toolchain add` or similar; CARGO_HOME is not because the user will need to
+# write there, and all rustup does here is to place some binaries that later
+# fan out to RUSTUP_HOME anyway.
+ENV RUSTUP_HOME /opt/rustup/.rustup
+RUN \
+    RUSTUP_HOME=/opt/rustup/.rustup \
+    CARGO_HOME=/opt/rustup/.cargo sh -c "\
+    curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile minimal --default-toolchain nightly-2021-08-28 && \
+    rustup target add i686-unknown-linux-gnu && \
+    rustup target add riscv32imac-unknown-none-elf && \
+    rustup target add thumbv7em-none-eabihf && \
+    rustup target add thumbv7em-none-eabi && \
+    rustup target add thumbv7m-none-eabi && \
+    rustup target add thumbv6m-none-eabi && \
+    true"
+
 # get Dockerfile version from build args
 ARG RIOTBUILD_VERSION=unknown
 ENV RIOTBUILD_VERSION $RIOTBUILD_VERSION
@@ -272,3 +301,6 @@ ENV RIOTBUILD_BRANCH $RIOTBUILD_BRANCH
 RUN echo "RIOTBUILD_VERSION=$RIOTBUILD_VERSION" > /etc/riotbuild
 RUN echo "RIOTBUILD_COMMIT=$RIOTBUILD_COMMIT" >> /etc/riotbuild
 RUN echo "RIOTBUILD_BRANCH=$RIOTBUILD_BRANCH" >> /etc/riotbuild
+
+# These depend on llvm-7-dev to be installed
+COPY --from=chrysn/c2rust-built /usr/bin/c2rust /usr/bin/c2rust-refactor /usr/bin/c2rust-transpile /usr/bin/