WIP squashfs-mount rootless, mutable root, bind mount

.editorconfig

@@ -0,0 +1,9 @@
+root = true
+
+[*.build]
+indent_style = space
+indent_size = 4
+
+[*{,cpp,h}]
+indent_style = space
+indent_size = 4

.github/workflows/build_and_test.yml

@@ -17,46 +17,62 @@ jobs:
           - buildtype: release
             sanitizer: address
     runs-on: ubuntu-24.04
+    container:
+        image: ubuntu:noble
+        options: --privileged
     steps:
       - uses: actions/checkout@v4
       - name: Update apt repositories for ccache
-        run: sudo apt update
+        run: apt update
       - name: Install dependencies
-        run: sudo apt-get install util-linux libmount-dev libslurm-dev
+        run: apt-get install --no-install-recommends --yes util-linux libmount-dev libslurm-dev
       #  run: sudo apt-get install util-linux libmount-dev slurm-wlm libslurm-dev slurmd slurmctld slurm-client
       - name: Set up ccache
         uses: hendrikmuhs/ccache-action@v1.2
         with:
           key: ccache-linux-${{ matrix.buildtype }}-${{ matrix.sanitizer }}
       - name: Install compiler and build tools
-        run: sudo apt install --no-install-recommends --yes g++-12 ninja-build
+        run: |
+            apt install --no-install-recommends --yes \
+               g++-12 \
+               ninja-build \
+               libsquashfuse-dev \
+               libfuse3-dev \
+               wget \
+               ca-certificates \
+               python3 \
+               pkg-config \
+               sqlite3 \
+               git \
+               squashfs-tools \
+               curl \
+               ninja-build \
+               locales
+
+            locale-gen en_US.UTF-8
+            update-locale LANG=en_US.UTF-8
       - name: install meson
         run: |
           wget https://github.com/mesonbuild/meson/releases/download/1.6.1/meson-1.6.1.tar.gz && \
           tar -xzf meson-1.6.1.tar.gz && \
           mv meson-1.6.1 meson && \
           mv meson/meson.py meson/meson
-      - name: install squashfs-mount
-        run: |
-          wget https://github.com/eth-cscs/squashfs-mount/archive/refs/tags/v1.1.0.tar.gz
-          tar -xzf v1.1.0.tar.gz
-          ./meson/meson setup build-sqfs squashfs-mount-1.1.0
-          ./meson/meson compile -C build-sqfs
-          sudo ./meson/meson install -C build-sqfs
       - name: Configure
         run: |
             CC="ccache gcc-12" CXX="ccache g++-12" ./meson/meson setup \
               --buildtype ${{ matrix.buildtype }} \
               -Db_sanitize=${{ matrix.sanitizer }} \
               -Dtests=enabled \
+              -Dfuse=true \
+              -Dsquashfs_mount=true \
               --warnlevel 3 \
               --werror \
               build .
       - name: Build
         run: ./meson/meson compile -Cbuild
       - name: test unit
-        run: ./meson/meson test -Cbuild --verbose unit
+        run: ./meson/meson test -v -Cbuild --verbose unit
       - name: test cli
         run: |
-          sudo mkdir /user-tools /user-environment
+          mkdir /user-tools /user-environment
           UENV_BATS_SKIP_START=on ./meson/meson test -Cbuild --verbose cli

install-alps-local.sh

@@ -1,11 +1,58 @@
 #!/bin/bash
 
-set -e
+set -eu
+
+# build static dependencies
+(
+    cd extern/
+    if [ ! -d "zstd-1.5.7/install/lib/pkgconfig" ]; then
+        (
+            curl -L https://github.com/facebook/zstd/releases/download/v1.5.7/zstd-1.5.7.tar.gz | tar xzf -
+            cd zstd-1.5.7/build/meson
+            CXX=g++-12 CC=gcc-12 uvx --with=meson,ninja \
+                       meson setup \
+                       --buildtype=release \
+                       -Dbin_programs=true \
+                       -Dbin_contrib=true \
+                       --prefix=$PWD/../../install \
+                       --wipe builddir
+            uvx --with=meson,ninja ninja -C builddir install
+            cd ../../install
+            # squashfuse expects a lib dir
+            ln -sf lib64 lib
+        )
+    fi
+
+    export ZSTD=$(realpath zstd-1.5.7/install)
+
+    if [ ! -d "squashfuse-0.6.1/install/lib/pkgconfig" ]; then
+        (
+            curl -L https://github.com/vasi/squashfuse/releases/download/0.6.1/squashfuse-0.6.1.tar.gz | tar xzf -
+            cd squashfuse-0.6.1
+
+            # patch includedir in pkg-config
+            sed -i 's/^includedir=.*/includedir=@includedir@/' squashfuse.pc.in
+            sed -i 's/^includedir=.*/includedir=@includedir@/' squashfuse_ll.pc.in
+
+            ./configure --disable-high-level \
+                --enable-static=yes \
+                --enable-shared=no \
+                --without-lzo \
+                --without-lz4 \
+                --with-zstd=$ZSTD \
+                --prefix=$PWD/install
+            make install
+        )
+    fi
+)
+
+PKG_CONFIG_PATH=$(realpath extern/zstd-1.5.7/install/lib/pkgconfig):$(realpath extern/squashfuse-0.6.1/install/lib/pkgconfig):${PKG_CONFIG_PATH:-}
+export PKG_CONFIG_PATH
 
 arch=$(uname -m)
 echo "== architecture: $arch"
 
-root=$(cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd)
+root=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" &>/dev/null && pwd)
 build=$root/build-alps-$arch
 pyenv=$root/pyenv-alps-$arch
 install=$HOME/.local/$arch
@@ -17,7 +64,7 @@ echo "== configure in $build"
 
 export CC=gcc-12
 export CXX=g++-12
-uvx --with meson,ninja meson setup --prefix=$install $build $root
+uvx --with meson,ninja meson setup -Dsquashfs_mount=true -Dfuse=true --prefix=$install $build $root
 uvx --with meson,ninja meson compile -C$build
 uvx --with meson,ninja meson install -C$build --skip-subprojects
 

meson-scripts/make-setuid.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+
+source="$1"
+target="$2"
+
+sudo cp $source $target
+sudo chown root:root "${target}"
+sudo chmod u+s "${target}"
+

meson.build

@@ -13,7 +13,7 @@ oras_version = get_option('oras_version')
 
 uenv_slurm_plugin = get_option('slurm_plugin')
 uenv_cli = get_option('cli')
-
+uenv_squashfs_mount = get_option('squashfs_mount')
 conf_data = configuration_data()
 
 add_global_arguments('-Wno-missing-field-initializers', language : 'cpp')
@@ -36,13 +36,16 @@ barkeep_dep = declare_dependency(
         compile_args: ['-DBARKEEP_ENABLE_FMT_FORMAT'],
 )
 
+libmount_dep = dependency('mount')
+
 # the lib dependency is all of the common funtionality shared between the CLI
 # and the slurm plugin.
 lib_src = [
         'src/site/site.cpp',
         'src/uenv/env.cpp',
         'src/uenv/log.cpp',
         'src/uenv/meta.cpp',
+        'src/uenv/mount.cpp',
         'src/uenv/oras.cpp',
         'src/uenv/parse.cpp',
         'src/uenv/print.cpp',
@@ -62,15 +65,15 @@ lib_src = [
 lib_inc = include_directories('src')
 
 lib_uenv = static_library(
-        'libuenv',
+        'uenv',
         lib_src,
         include_directories: lib_inc,
         dependencies: [curl_dep, sqlite3_dep, fmt_dep, spdlog_dep, json_dep, barkeep_dep],
 )
 
 uenv_dep = declare_dependency(
         link_with: lib_uenv,
-        dependencies: [curl_dep, sqlite3_dep, fmt_dep, spdlog_dep, json_dep, barkeep_dep],
+        dependencies: [curl_dep, sqlite3_dep, fmt_dep, spdlog_dep, json_dep, barkeep_dep, libmount_dep],
         include_directories: lib_inc
 )
 
@@ -133,9 +136,46 @@ if uenv_cli
 endif
 
 if uenv_slurm_plugin
-    subdir('src/slurm')
+  subdir('src/slurm')
 endif
 
+if uenv_squashfs_mount
+    if get_option('fuse')
+        fuse_dep = dependency('fuse@0@'.format(get_option('fuse_version')))
+        squashfuse_dep = dependency('squashfuse_ll', static: false)
+        squashfs_mount_build = executable('squashfs-mount',
+                                          sources: ['src/squashfs-mount/squashfs-mount-rootless.cpp',
+                                                    'src/squashfs-mount/rootless.cpp',
+                                                    'src/squashfs-mount/mutable-root.cpp'
+                                                   ],
+                                          dependencies: [uenv_dep, fmt_dep, cli11_dep, squashfuse_dep, fuse_dep],
+                                          c_args: [
+                                              '-DVERSION="@0@"'.format(version),
+                                          ],
+                                          install: true
+                                         )
+    else
+        message('NOT iusing fuse')
+        squashfs_mount_build = executable('squashfs-mount-build',
+                                          sources: ['src/squashfs-mount/squashfs-mount.cpp'],
+                                          dependencies: [uenv_dep, fmt_dep, cli11_dep],
+                                          c_args: [
+                                              '-DVERSION="@0@"'.format(version),
+                                          ],
+                                          install: false)
+
+        squashfs_mount = custom_target(
+            'squashfs-mount',
+            input: squashfs_mount_build,
+            output: 'squashfs-mount',
+            command: ['./meson-scripts/make-setuid.sh', '@INPUT@', '@OUTPUT@'],
+            install: true,
+            install_dir: get_option('bindir'),
+        )
+    endif
+endif
+
+
 if get_option('tests').enabled()
     subdir('test')
 endif

meson_options.txt

@@ -2,5 +2,7 @@ option('tests', type: 'feature', value: 'disabled')
 
 option('slurm_plugin', type: 'boolean', value: true)
 option('cli', type: 'boolean', value: true)
-
+option('squashfs_mount', type: 'boolean', value: false)
+option('fuse', type: 'boolean', value: true)
+option('fuse_version', type: 'string', value: '3')
 option('oras_version', type: 'string', value: '1.2.0')

src/cli/run.cpp

@@ -1,5 +1,6 @@
 // vim: ts=4 sts=4 sw=4 et
 
+#include <ranges>
 #include <string>
 
 #include <fmt/core.h>
@@ -64,16 +65,26 @@ You need to finish the current session by typing 'exit' or hitting '<ctrl-d>'.)"
 
     // generate the mount list
     std::vector<std::string> commands = {"squashfs-mount"};
-    for (auto e : env->uenvs) {
-        commands.push_back(fmt::format("{}:{}", e.second.sqfs_path.string(),
-                                       e.second.mount_path));
-    }
+    commands.push_back(fmt::format(
+        "--sqfs={}",
+        fmt::join(env->uenvs | std::views::transform([](const auto& in) {
+                      return fmt::format("{}:{}", in.second.sqfs_path.string(),
+                                         in.second.mount_path);
+                  }),
+                  ",")));
 
     commands.push_back("--");
     commands.insert(commands.end(), args.commands.begin(), args.commands.end());
 
-    // return util::exec(commands);
-    return util::exec(commands, runtime_environment.c_env());
+    auto c_env = runtime_environment.c_env();
+    auto rcode = util::exec(commands, c_env);
+
+    // clean up memory if there was an error
+    if (rcode) {
+        envvars::c_env_free(c_env);
+    }
+
+    return rcode;
 }
 
 std::string run_footer() {

src/cli/start.cpp

@@ -1,6 +1,7 @@
 // vim: ts=4 sts=4 sw=4 et
 #include <unistd.h>
 
+#include <ranges>
 #include <string>
 
 #include <fmt/core.h>
@@ -107,10 +108,13 @@ will not work, because it starts a new interactive shell.)",
 
     // generate the mount list
     std::vector<std::string> commands = {"squashfs-mount"};
-    for (auto e : env->uenvs) {
-        commands.push_back(fmt::format("{}:{}", e.second.sqfs_path.string(),
-                                       e.second.mount_path));
-    }
+    commands.push_back(fmt::format(
+        "--sqfs={}",
+        fmt::join(env->uenvs | std::views::transform([](const auto& in) {
+                      return fmt::format("{}:{}", in.second.sqfs_path.string(),
+                                         in.second.mount_path);
+                  }),
+                  ",")));
 
     // find the current shell (zsh, bash, etc)
     auto shell = util::current_shell(globals.calling_environment);
@@ -124,7 +128,15 @@ will not work, because it starts a new interactive shell.)",
     commands.push_back("--");
     commands.push_back(shell->string());
 
-    return util::exec(commands, runtime_environment.c_env());
+    auto c_env = runtime_environment.c_env();
+    auto rcode = util::exec(commands, c_env);
+
+    // clean up memory if there was an error
+    if (rcode) {
+        envvars::c_env_free(c_env);
+    }
+
+    return rcode;
 }
 
 std::string start_footer() {

src/cli/uenv.cpp

@@ -6,9 +6,8 @@
 #include <fmt/std.h>
 #include <spdlog/spdlog.h>
 
-#include <uenv/log.h>
-
 #include <uenv/config.h>
+#include <uenv/log.h>
 #include <uenv/parse.h>
 #include <uenv/repository.h>
 #include <uenv/settings.h>

src/slurm/meson.build

@@ -5,15 +5,11 @@ configure_file(input : 'config.hpp.in',
                output : 'config.hpp',
                configuration : conf_data)
 
-libmount_dep = dependency('mount')
-
-module_src = ['plugin.cpp', 'mount.cpp']
-
-module_dep = [libmount_dep, sqlite3_dep, uenv_dep]
+module_src = ['plugin.cpp', 'mount_slurm.cpp']
 
 shared_module('slurm-uenv-mount',
               sources: module_src,
-              dependencies: module_dep,
+              dependencies: uenv_dep,
               cpp_args: ['-Wall', '-Wpedantic', '-Wextra'],
               install: true)