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nix/oe-nix-shell

@@ -0,0 +1,134 @@
+#!/bin/bash
+
+# Copyright (c) Open Enclave SDK contributors.
+# Licensed under the MIT License.
+
+USAGE="
+Usage:  oe-nix-shell [command]
+        oe-nix-shell -help
+
+To enter into OE SDK build shell, type oe-nix-shell
+without any arguments. It will bring up a prompt:
+   [nix-shell:pwd]$
+
+This is a nix-shell that has all the tools necessary
+for building the OE SDK. To quit the shell, type exit.
+
+To execute a command and immediately exit the shell,
+provide the command in quotes.
+   oe-nix-shell \"cd build && make -j 16\"
+
+This will enter the shell, change to the build folder, 
+build the SDK and exit the shell.
+"
+
+# Print usage if wrong arguments supplied.
+if [ "$#" -gt 1 ]; then
+  echo "${USAGE}"
+  exit 1
+fi
+
+# Print usage if requested.
+if [ "$1" == "-help" ]; then
+  echo "${USAGE}"
+  exit 0
+fi
+
+# If no command is specified, use return;
+# as the command to prevent nix-shell from 
+# exiting.
+CMD="$1"
+if [ "$#" -eq 0 ]; then
+  CMD="return;"
+fi
+
+# Fetch the directory of oe-nix-shell script.
+OE_NIX_SHELL_SCRIPT_DIR=$(dirname "$(readlink -f "${BASH_SOURCE[0]}")")
+
+# Command to enter into OE SDK nix shell
+OE_NIX_SHELL_CMD="nix-shell \"${OE_NIX_SHELL_SCRIPT_DIR}/shell.nix\" --pure \
+  --command \"neofetch; \
+  echo Welcome to OE SDK build shell; \
+  ${CMD}\""
+
+# If nix is available in path, use it.
+if command -v nix-shell &> /dev/null
+then
+  bash -c "${OE_NIX_SHELL_CMD}" 
+  exit 0
+fi
+
+
+# Path to profile in single user mode install of nix.
+NIX_PROFILE=~/.nix-profile/etc/profile.d/nix.sh
+
+# If root user, then install nix as per instructions here:
+#  https://github.com/NixOS/nix/issues/936
+if [ "$EUID" -eq 0 ]; then
+
+  # Set user so that nix profile gets loaded correctly.
+  export USER=root
+
+  # If a profile exists, the load it.
+  if test -f "${NIX_PROFILE}"; then
+    source "${NIX_PROFILE}"
+  fi
+
+  #If nix-shell exists, use it.
+  if command -v nix-shell > /dev/null; then
+    bash -c "${OE_NIX_SHELL_CMD}"
+    exit 0
+  fi
+
+  # Install nix for root user.
+  # First create /nix folder
+  mkdir -p -m 0755 /nix
+
+  # Create empty build-users-group
+  mkdir -p /etc/nix
+  echo "build-users-group =" > /etc/nix/nix.conf
+
+  # Install nix.
+  # Assume debian based distro for now.
+  apt-get install -y curl
+  wget https://nixos.org/nix/install -O install.sh
+  curl -L https://nixos.org/nix/install | sh
+
+  bash -c "source ${NIX_PROFILE} && ${OE_NIX_SHELL_CMD}"
+  exit 0
+fi
+
+
+# Path to nix-user-chroot binary.
+NIX_USER_CHROOT=~/.oe-nix/nix-user-chroot
+
+# Path to nix directory
+NIX_DIR=~/.oe-nix/.nix
+
+# Ensure that OE nix directory exists.
+mkdir -m 0755 -p ${NIX_DIR}
+# Download nix-user-chroot
+if ! test -f "${NIX_USER_CHROOT}"
+then
+  echo "Downloading nix-user-chroot"
+  mkdir -p ~/.oe-nix
+  wget https://github.com/nix-community/nix-user-chroot/releases/download/1.1.1/nix-user-chroot-bin-1.1.1-x86_64-unknown-linux-musl \
+         -O "${NIX_USER_CHROOT}"
+  chmod +x "${NIX_USER_CHROOT}"
+fi
+
+
+# Check if nix has been installed in the user chroot.
+if ! "${NIX_USER_CHROOT}"  "${NIX_DIR}" \
+        bash -c "source ${NIX_PROFILE} && \
+              which nix-shell > /dev/null"
+then
+  # Install nix in the user chroot.
+  "${NIX_USER_CHROOT}" "${NIX_DIR}" \
+         bash -c  "sh <(curl -L https://nixos.org/nix/install) --no-daemon"
+fi
+
+# Enter the shell.
+"${NIX_USER_CHROOT}" "${NIX_DIR}" \
+  bash -c "source ${NIX_PROFILE} && ${OE_NIX_SHELL_CMD}"
+

nix/shell.nix

@@ -0,0 +1,123 @@
+let
+  # Let's choose the most recent nixpkgs release for installing
+  # most packages. The URL for nixpkgs tarball can be found from
+  # will be installed. The URL for the channel can be found from
+  #          https://github.com/NixOS/nixpkgs/releases
+  # Nix has a 6 month release cycle and the releases are typically
+  # numbered year.03 and year.09.
+  # Using tarballs is *much* faster than using git to clone the
+  # nixpkgs repo. Additionally, tarballs pin the packages to
+  # specific versions.
+  # To obtain the sha256 for a tarball do:
+  #     nix-prefetch-url --unpack <tar-ball-url>
+  # That will fetch the tarball, unpack it and print the sha256.
+  pkgs = import (builtins.fetchTarball {
+    url = "https://github.com/NixOS/nixpkgs/archive/20.09.tar.gz";
+    sha256 = "1wg61h4gndm3vcprdcg7rc4s1v3jkm5xd7lw8r2f67w502y94gcy";
+  }) {};
+
+  # Some build tools like clang exist as different packages e.g
+  # clang_8, clang_9 etc in the same nixpkgs release. So it is
+  # trivial to choose the appropriate one: pkgs.clang_8 or pkgs.clang_9.
+  # Other packages like clang-format-7 may not be available in the latest
+  # nixpkg release. To find out how to install an older version of
+  # package, choose the channel and the specify the package name here:
+  #    https://lazamar.co.uk/nix-versions/
+  # That will bring up a list of older versions of the package.
+  # Clicking on the version we want will provide the nix code for
+  # installing that specific package.
+  # For example, the following lists older revisions of clang-tools:
+  #    https://lazamar.co.uk/nix-versions/?channel=nixos-20.03&package=clang-tools
+  # The instructions for version 7.0.1 provide us the path to the tarball.
+  olderPkgs = import (builtins.fetchTarball {
+    url = "https://github.com/NixOS/nixpkgs/archive/7ff8a16f0726342f0a25697867d8c1306d4da7b0.tar.gz";
+    sha256 = "0gwwwzriq4vv0v468mrx17lrmzr34lcdccmsxdfmw7z85fm8afdl";
+  }) {};
+in
+  # Create development environment for building OE SDK.
+  # stdenvNoCC means that GCC (default) ought not be made available.
+  pkgs.stdenvNoCC.mkDerivation ({
+    name = "oe-build-env";
+    buildInputs = [
+       # It is good to have git within the shell
+       # to work with other repos.
+       # version=2.29.2
+       pkgs.git
+
+       # version=3.18.2
+       pkgs.cmake
+
+       # Order of package declaration matters.
+       # Specify clang-tools first so that the
+       # older clang-format (7.0.1) appears before the
+       # newer clang-format (8.0.1) that is part of clang_8.
+       # version=7.0.1
+       olderPkgs.clang-tools
+
+       # OE SDK is built using clang.
+       # version=8.0.1
+       pkgs.clang_8
+
+       # Use ccache to speed up recompilation.
+       # See shellHooks for configuration.
+       pkgs.ccache
+
+       # Allow using ninja instead of make.
+       # version=1�10.1
+       pkgs.ninja
+
+       # OpenSSL tests require. Perl.
+       # The specific version may not matter.
+       # version=5.32.0
+       pkgs.perl
+
+       # Python is used in many places in the SDK.
+       # See shellHooks for how cmake-format is setup.
+       # version=3.8.5
+       pkgs.python3
+
+       # Recent version of openssl is used.
+       # This may need to be selectively updated as newer
+       # versions are released.
+       # version=1.1.1g
+       pkgs.openssl
+
+       # Doxygen for SDK document generation.
+       # version=1.8.19
+       pkgs.doxygen
+
+       # Graphviz is needed for the dot commant used by the
+       # document generation.
+       # dot version=2.43.0
+       pkgs.graphviz
+
+       # Needed for debugging the SDK. 
+       # version=9.2
+       pkgs.gdb
+
+       # Fun
+       pkgs.neofetch
+    ];
+    shellHooks = ''
+      # Set up C and C++ compilers explicitly via
+      # environment variables. This ensures that
+      # these compilers are picked up even if the
+      # shell has some other compilers lying around.
+      export CC=clang
+      export CXX=clang++
+
+      # Set up the base dir so that ccache uses relative
+      # paths from the base dir. This will result in
+      # cache hits across many local repos.
+      export CCACHE_BASEDIR=`pwd`
+
+      # Setup python virtual env and install cmake-format.
+      # There might be better ways to install cmake-format in
+      # nix, but this is good enough for now.
+      rm -rf .venv
+      python -m venv .venv
+      source .venv/bin/activate
+      # Send "upgrade pip" warning to /dev/null.
+      pip install cmake-format==0.6.9 2>/dev/null
+    '';
+  })

test/CMakeLists.txt

@@ -8,6 +8,11 @@ add_subdirectory(call_conflict)
 add_subdirectory(cmdline)
 add_subdirectory(comprehensive)
 add_subdirectory(import)
+
+if (UNIX)
+  add_subdirectory(nix)
+endif ()
+
 add_subdirectory(prefix)
 add_subdirectory(preprocessor)
 add_subdirectory(safe_math)

test/nix/CMakeLists.txt

@@ -0,0 +1,17 @@
+# Copyright (c) Open Enclave SDK contributors.
+# Licensed under the MIT License.
+
+set(PASS_STRING "oe-nix-shell build completed")
+
+add_test(
+  NAME oe-nix-shell-test
+  COMMAND
+    ${PROJECT_SOURCE_DIR}/nix/oe-nix-shell "rm -rf build && \
+	   mkdir build && \
+	   cd build && \
+	   cmake ${PROJECT_SOURCE_DIR} && \
+	   make -j 8 && \
+	   echo ${PASS_STRING}")
+
+set_tests_properties(oe-nix-shell-test PROPERTIES PASS_REGULAR_EXPRESSION
+                                                  "Intentionally fail the test to look at the test logs")

test/nix/Testing/Temporary/CTestCostData.txt

@@ -0,0 +1 @@
+---

test/nix/Testing/Temporary/LastTest.log

@@ -0,0 +1,3 @@
+Start testing: Feb 05 14:32 PST
+----------------------------------------------------------
+End testing: Feb 05 14:32 PST