👷 gucc: add function to merge subvolumes into partition scheme

.github/workflows/build.yml

@@ -46,6 +46,7 @@ jobs:
           ./gucc/tests/test-fetch_file
           ./gucc/tests/test-locale
           ./gucc/tests/test-package_profiles
+          ./gucc/tests/test-btrfs
         shell: bash
   build-cmake_withoutdev:
     name: Build with CMake (DEVENV OFF)
@@ -98,6 +99,7 @@ jobs:
           ./gucc/tests/test-fetch_file
           ./gucc/tests/test-locale
           ./gucc/tests/test-package_profiles
+          ./gucc/tests/test-btrfs
         shell: bash
   build-meson_withoutdev:
     name: Build with Meson (DEVENV OFF)

gucc/include/gucc/btrfs.hpp

@@ -1,6 +1,8 @@
 #ifndef BTRFS_HPP
 #define BTRFS_HPP
 
+#include "gucc/partition.hpp"
+
 #include <string>       // for string
 #include <string_view>  // for string_view
 #include <vector>       // for vector
@@ -21,6 +23,10 @@ auto btrfs_create_subvols(const std::vector<BtrfsSubvolume>& subvols, std::strin
 // Mounts btrfs subvolumes
 auto btrfs_mount_subvols(const std::vector<BtrfsSubvolume>& subvols, std::string_view device, std::string_view root_mountpoint, std::string_view mount_opts) noexcept -> bool;
 
+// Appends btrfs subvolumes into Partition scheme
+// with sorting scheme by device field
+auto btrfs_append_subvolumes(std::vector<Partition>& partitions, const std::vector<BtrfsSubvolume>& subvols) noexcept -> bool;
+
 }  // namespace gucc::fs
 
 #endif  // BTRFS_HPP

gucc/src/btrfs.cpp

@@ -1,20 +1,26 @@
 #include "gucc/btrfs.hpp"
 #include "gucc/io_utils.hpp"
+#include "gucc/partition.hpp"
 
-#include <filesystem>
+#include <algorithm>   // for find_if
+#include <filesystem>  // for create_directories
+#include <optional>    // for optional
+#include <ranges>      // for ranges::*
+#include <utility>     // for make_optional
 
 #include <fmt/compile.h>
 #include <fmt/format.h>
 
 #include <spdlog/spdlog.h>
 
 namespace fs = std::filesystem;
+using namespace std::string_view_literals;
 
 namespace {
 
 // same behaviour as os.path.dirname from python
 constexpr auto get_dirname(std::string_view full_path) noexcept -> std::string_view {
-    if (full_path == "/") {
+    if (full_path == "/"sv) {
         return full_path;
     }
     auto pos = full_path.find_last_of('/');
@@ -24,6 +30,19 @@ constexpr auto get_dirname(std::string_view full_path) noexcept -> std::string_v
     return full_path.substr(0, pos);
 }
 
+constexpr auto find_partition(const gucc::fs::Partition& part, const gucc::fs::BtrfsSubvolume& subvol) noexcept -> bool {
+    return (part.mountpoint == subvol.mountpoint) || (part.subvolume && *part.subvolume == subvol.subvolume);
+}
+
+constexpr auto is_root_btrfs_part(const gucc::fs::Partition& part) noexcept -> bool {
+    return (part.mountpoint == "/"sv) && (part.fstype == "btrfs"sv);
+}
+
+constexpr auto find_root_btrfs_part(auto&& parts) noexcept {
+    return std::ranges::find_if(parts,
+        [](auto&& part) { return is_root_btrfs_part(part); });
+}
+
 }  // namespace
 
 namespace gucc::fs {
@@ -92,4 +111,51 @@ auto btrfs_mount_subvols(const std::vector<BtrfsSubvolume>& subvols, std::string
     return true;
 }
 
+auto btrfs_append_subvolumes(std::vector<Partition>& partitions, const std::vector<BtrfsSubvolume>& subvols) noexcept -> bool {
+    // if the list of subvolumes is empty, just return success at the beginning of the function
+    if (subvols.empty()) {
+        return true;
+    }
+
+    auto root_part_it = find_root_btrfs_part(partitions);
+    if (root_part_it == std::ranges::end(partitions)) {
+        spdlog::error("Unable to find root btrfs partition!");
+        return false;
+    }
+
+    for (auto&& subvol : subvols) {
+        // check if we already have a partition with such subvolume
+        auto part_it = std::ranges::find_if(partitions,
+            [&subvol](auto&& part) { return find_partition(part, subvol); });
+
+        // we have found it. proceed to overwrite the values
+        if (part_it != std::ranges::end(partitions)) {
+            part_it->mountpoint = subvol.mountpoint;
+            part_it->subvolume  = std::make_optional<std::string>(subvol.subvolume);
+            continue;
+        }
+        // overwise, let's insert the partition based on the root partition
+
+        // NOTE: we don't need to check for root part here,
+        // because it was already checked in the beginning
+        root_part_it = find_root_btrfs_part(partitions);
+
+        Partition part{};
+        part.fstype           = root_part_it->fstype;
+        part.mountpoint       = subvol.mountpoint;
+        part.uuid_str         = root_part_it->uuid_str;
+        part.device           = root_part_it->device;
+        part.mount_opts       = root_part_it->mount_opts;
+        part.subvolume        = std::make_optional<std::string>(subvol.subvolume);
+        part.luks_mapper_name = root_part_it->luks_mapper_name;
+        part.luks_uuid        = root_part_it->luks_uuid;
+        part.luks_passphrase  = root_part_it->luks_passphrase;
+        partitions.emplace_back(std::move(part));
+    }
+
+    // sort by device
+    std::ranges::sort(partitions, {}, &Partition::device);
+    return true;
+}
+
 }  // namespace gucc::fs

gucc/tests/meson.build

@@ -77,3 +77,11 @@ executable(
   link_with: [gucc_lib],
   include_directories: [include_directories('../include')],
   install: false)
+
+executable(
+  'test-btrfs',
+  files('unit-btrfs.cpp'),
+  dependencies: deps,
+  link_with: [gucc_lib],
+  include_directories: [include_directories('../include')],
+  install: false)

gucc/tests/unit-btrfs.cpp

@@ -0,0 +1,141 @@
+#include "gucc/btrfs.hpp"
+#include "gucc/logger.hpp"
+
+#include <cassert>
+
+#include <string>
+#include <string_view>
+#include <vector>
+
+#include <spdlog/sinks/callback_sink.h>
+#include <spdlog/spdlog.h>
+
+using namespace std::string_literals;
+using namespace std::string_view_literals;
+
+int main() {
+    auto callback_sink = std::make_shared<spdlog::sinks::callback_sink_mt>([](const spdlog::details::log_msg&) {
+        // noop
+    });
+    auto logger        = std::make_shared<spdlog::logger>("default", callback_sink);
+    spdlog::set_default_logger(logger);
+    gucc::logger::set_logger(logger);
+
+    const std::vector<gucc::fs::BtrfsSubvolume> subvolumes{
+        gucc::fs::BtrfsSubvolume{.subvolume = "/@"s, .mountpoint = "/"s},
+        gucc::fs::BtrfsSubvolume{.subvolume = "/@home"s, .mountpoint = "/home"s},
+        gucc::fs::BtrfsSubvolume{.subvolume = "/@cache"s, .mountpoint = "/var/cache"s},
+        // gucc::fs::BtrfsSubvolume{.subvolume = "/@snapshots"sv, .mountpoint = "/.snapshots"sv},
+    };
+
+    // btrfs with subvolumes
+    {
+        const std::vector<gucc::fs::Partition> expected_partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@"s},
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/home"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@home"s},
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/var/cache"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@cache"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        std::vector<gucc::fs::Partition> partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        assert(gucc::fs::btrfs_append_subvolumes(partitions, subvolumes));
+        assert(partitions.size() == 4);
+        assert(partitions == expected_partitions);
+    }
+    // invalid btrfs with subvolumes
+    {
+        const std::vector<gucc::fs::Partition> expected_partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/home"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@home"s},
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/var/cache"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@cache"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        std::vector<gucc::fs::Partition> partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/home"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@home"s},
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/var/cache"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@cache"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        assert(!gucc::fs::btrfs_append_subvolumes(partitions, subvolumes));
+        assert(partitions.size() == 3);
+        assert(partitions == expected_partitions);
+    }
+    // invalid (without root part) btrfs with subvolumes
+    {
+        const std::vector<gucc::fs::Partition> expected_partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/home"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@home"s},
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/var/cache"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@cache"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        std::vector<gucc::fs::Partition> partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/home"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@home"s},
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/var/cache"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@cache"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        assert(!gucc::fs::btrfs_append_subvolumes(partitions, subvolumes));
+        assert(partitions.size() == 3);
+        assert(partitions == expected_partitions);
+    }
+    // btrfs without subvolumes
+    {
+        const std::vector<gucc::fs::Partition> expected_partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        std::vector<gucc::fs::Partition> partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        assert(gucc::fs::btrfs_append_subvolumes(partitions, {}));
+        assert(partitions.size() == 2);
+        assert(partitions == expected_partitions);
+    }
+    // luks xfs
+    {
+        const std::vector<gucc::fs::Partition> expected_partitions{
+            gucc::fs::Partition{.fstype = "xfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,lazytime,noatime,attr2,inode64,logbsize=256k,noquota"s, .luks_mapper_name = "luks_device"s, .luks_uuid = "00e1b836-81b6-433f-83ca-0fd373e3cd50"s},
+            gucc::fs::Partition{.fstype = "linuxswap"s, .mountpoint = ""s, .uuid_str = ""s, .device = "/dev/nvme0n1p3"s, .mount_opts = "defaults,noatime"s},
+            gucc::fs::Partition{.fstype = "vfat"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        std::vector<gucc::fs::Partition> partitions{
+            gucc::fs::Partition{.fstype = "xfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,lazytime,noatime,attr2,inode64,logbsize=256k,noquota"s, .luks_mapper_name = "luks_device"s, .luks_uuid = "00e1b836-81b6-433f-83ca-0fd373e3cd50"s},
+            gucc::fs::Partition{.fstype = "linuxswap"s, .mountpoint = ""s, .uuid_str = ""s, .device = "/dev/nvme0n1p3"s, .mount_opts = "defaults,noatime"s},
+            gucc::fs::Partition{.fstype = "vfat"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        assert(!gucc::fs::btrfs_append_subvolumes(partitions, subvolumes));
+        assert(partitions == expected_partitions);
+    }
+    // valid zfs
+    {
+        const std::vector<gucc::fs::Partition> expected_partitions{
+            gucc::fs::Partition{.fstype = "zfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "zfs"s, .mountpoint = "/home"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "zfs"s, .mountpoint = "/var/cache"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "vfat"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        std::vector<gucc::fs::Partition> partitions{
+            gucc::fs::Partition{.fstype = "zfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "zfs"s, .mountpoint = "/home"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "zfs"s, .mountpoint = "/var/cache"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s},
+            gucc::fs::Partition{.fstype = "vfat"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        assert(!gucc::fs::btrfs_append_subvolumes(partitions, subvolumes));
+        assert(partitions == expected_partitions);
+    }
+    // luks btrfs with subvolumes
+    {
+        const std::vector<gucc::fs::Partition> expected_partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@"s, .luks_mapper_name = "luks-6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .luks_uuid = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s},
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/home"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@home"s, .luks_mapper_name = "luks-6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .luks_uuid = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s},
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/var/cache"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@cache"s, .luks_mapper_name = "luks-6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .luks_uuid = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        std::vector<gucc::fs::Partition> partitions{
+            gucc::fs::Partition{.fstype = "btrfs"s, .mountpoint = "/"s, .uuid_str = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .device = "/dev/nvme0n1p1"s, .mount_opts = "defaults,noatime,compress=zstd,space_cache=v2,commit=120"s, .subvolume = "/@"s, .luks_mapper_name = "luks-6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s, .luks_uuid = "6bdb3301-8efb-4b84-b0b7-4caeef26fd6f"s},
+            gucc::fs::Partition{.fstype = "fat32"s, .mountpoint = "/boot"s, .uuid_str = "8EFB-4B84"s, .device = "/dev/nvme0n1p2"s, .mount_opts = "defaults,noatime"s},
+        };
+        assert(gucc::fs::btrfs_append_subvolumes(partitions, subvolumes));
+        assert(partitions.size() == 4);
+        assert(partitions == expected_partitions);
+    }
+}