Move the VminitdCore library to the top-level package (#742)

External Swift Package Manager consumers can only see products declared
in the top-level `Package.swift`. The `VminitdCore` library was declared
inside the `vminitd` subpackage, so it was impossible to build a custom
`vminitd` against it via a URL dependency on `containerization`. This
change moves the `VminitdCore` to the top-level `Package.swift`.

Author: dkovba

.gitignore

@@ -7,7 +7,6 @@ xcuserdata/
 DerivedData/
 .swiftpm/
 .netrc
-.swiftpm
 workdir/
 installer/
 .venv/

Package.swift

@@ -21,6 +21,10 @@ import CompilerPluginSupport
 import Foundation
 import PackageDescription
 
+let gitCommit = ProcessInfo.processInfo.environment["GIT_COMMIT"] ?? "unspecified"
+let gitTag = ProcessInfo.processInfo.environment["GIT_TAG"] ?? ""
+let buildTime = ProcessInfo.processInfo.environment["BUILD_TIME"] ?? "unspecified"
+
 let package = Package(
     name: "containerization",
     platforms: [.macOS("15.0")],
@@ -33,6 +37,7 @@ let package = Package(
         .library(name: "ContainerizationOS", targets: ["ContainerizationOS"]),
         .library(name: "ContainerizationExtras", targets: ["ContainerizationExtras"]),
         .library(name: "ContainerizationArchive", targets: ["ContainerizationArchive"]),
+        .library(name: "VminitdCore", targets: ["VminitdCore", "Cgroup", "LCShim"]),
         .executable(name: "cctl", targets: ["cctl"]),
     ],
     dependencies: [
@@ -259,6 +264,50 @@ let package = Package(
         .target(
             name: "CShim"
         ),
+        .target(
+            name: "CVersion",
+            path: "vminitd/Sources/CVersion",
+            cSettings: [
+                .define("GIT_COMMIT", to: "\"\(gitCommit)\""),
+                .define("GIT_TAG", to: "\"\(gitTag)\""),
+                .define("BUILD_TIME", to: "\"\(buildTime)\""),
+            ]
+        ),
+        .target(
+            name: "LCShim",
+            path: "vminitd/Sources/LCShim"
+        ),
+        .target(
+            name: "Cgroup",
+            dependencies: [
+                .product(name: "Logging", package: "swift-log"),
+                "ContainerizationOCI",
+                "ContainerizationOS",
+                .product(name: "SystemPackage", package: "swift-system"),
+                "LCShim",
+            ],
+            path: "vminitd/Sources/Cgroup"
+        ),
+        .target(
+            name: "VminitdCore",
+            dependencies: [
+                .product(name: "ArgumentParser", package: "swift-argument-parser"),
+                .product(name: "Logging", package: "swift-log"),
+                "Containerization",
+                "ContainerizationArchive",
+                "ContainerizationNetlink",
+                "ContainerizationIO",
+                "ContainerizationOS",
+                .product(name: "SystemPackage", package: "swift-system"),
+                .product(name: "GRPCCore", package: "grpc-swift-2"),
+                .product(name: "GRPCNIOTransportHTTP2", package: "grpc-swift-nio-transport"),
+                .product(name: "GRPCProtobuf", package: "grpc-swift-protobuf"),
+                "LCShim",
+                "CVersion",
+                "Cgroup",
+            ],
+            path: "vminitd/Sources/VminitdCore"
+        ),
     ]
 )
 

vminitd/Package.swift

@@ -17,79 +17,29 @@
 
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
-import Foundation
 import PackageDescription
 
-let gitCommit = ProcessInfo.processInfo.environment["GIT_COMMIT"] ?? "unspecified"
-let gitTag = ProcessInfo.processInfo.environment["GIT_TAG"] ?? ""
-let buildTime = ProcessInfo.processInfo.environment["BUILD_TIME"] ?? "unspecified"
-
 let package = Package(
     name: "swift-vminitd",
     platforms: [.macOS("15")],
     products: [
-        .library(name: "VminitdCore", targets: ["VminitdCore"]),
         .executable(name: "vminitd", targets: ["vminitd"]),
         .executable(name: "vmexec", targets: ["vmexec"]),
     ],
     dependencies: [
         .package(url: "https://github.com/apple/swift-argument-parser", from: "1.7.0"),
         .package(url: "https://github.com/apple/swift-log.git", from: "1.10.1"),
-        .package(url: "https://github.com/apple/swift-protobuf.git", from: "1.36.0"),
         .package(url: "https://github.com/apple/swift-system.git", from: "1.6.4"),
-        .package(url: "https://github.com/grpc/grpc-swift-2.git", from: "2.3.0"),
-        .package(url: "https://github.com/grpc/grpc-swift-nio-transport.git", from: "2.4.4"),
-        .package(url: "https://github.com/grpc/grpc-swift-protobuf.git", from: "2.2.0"),
         .package(name: "containerization", path: "../"),
     ],
     targets: [
-        .target(
-            name: "CVersion",
-            cSettings: [
-                .define("GIT_COMMIT", to: "\"\(gitCommit)\""),
-                .define("GIT_TAG", to: "\"\(gitTag)\""),
-                .define("BUILD_TIME", to: "\"\(buildTime)\""),
-            ]
-        ),
-        .target(
-            name: "LCShim"
-        ),
-        .target(
-            name: "Cgroup",
-            dependencies: [
-                .product(name: "Logging", package: "swift-log"),
-                .product(name: "ContainerizationOCI", package: "containerization"),
-                .product(name: "ContainerizationOS", package: "containerization"),
-                .product(name: "SystemPackage", package: "swift-system"),
-                "LCShim",
-            ]
-        ),
-        .target(
-            name: "VminitdCore",
-            dependencies: [
-                .product(name: "ArgumentParser", package: "swift-argument-parser"),
-                .product(name: "Logging", package: "swift-log"),
-                .product(name: "Containerization", package: "containerization"),
-                .product(name: "ContainerizationArchive", package: "containerization"),
-                .product(name: "ContainerizationNetlink", package: "containerization"),
-                .product(name: "ContainerizationIO", package: "containerization"),
-                .product(name: "ContainerizationOS", package: "containerization"),
-                .product(name: "SystemPackage", package: "swift-system"),
-                .product(name: "GRPCCore", package: "grpc-swift-2"),
-                .product(name: "GRPCNIOTransportHTTP2", package: "grpc-swift-nio-transport"),
-                .product(name: "GRPCProtobuf", package: "grpc-swift-protobuf"),
-                "LCShim",
-                "CVersion",
-                "Cgroup",
-            ]
-        ),
         .executableTarget(
             name: "vminitd",
             dependencies: [
                 .product(name: "ArgumentParser", package: "swift-argument-parser"),
                 .product(name: "ContainerizationOS", package: "containerization"),
                 .product(name: "Logging", package: "swift-log"),
-                "VminitdCore",
+                .product(name: "VminitdCore", package: "containerization"),
             ]
         ),
         .executableTarget(
@@ -100,8 +50,7 @@ let package = Package(
                 .product(name: "SystemPackage", package: "swift-system"),
                 .product(name: "Containerization", package: "containerization"),
                 .product(name: "ContainerizationOS", package: "containerization"),
-                "LCShim",
-                "Cgroup",
+                .product(name: "VminitdCore", package: "containerization"),
             ]
         ),
     ]

vminitd/Sources/Cgroup/Cgroup2Manager.swift

@@ -14,12 +14,12 @@
 // limitations under the License.
 //===----------------------------------------------------------------------===//
 
+#if os(Linux)
+
 // NOTE: Ideally this should live in ContainerizationOS/Linux, or just ContainerizationCgroups
 // or something similar, but it's not there yet. It does what we need, but it'd need a lot more
 // features and testing before it's ready to be public.
 
-#if os(Linux)
-
 #if canImport(Musl)
 import Musl
 #elseif canImport(Glibc)
@@ -43,8 +43,8 @@ package enum Cgroup2Controller: String {
 
 // Extremely simple cgroup manager. Our needs are simple for now, and this is
 // reflected in the type.
-package struct Cgroup2Manager: Sendable {
-    package static let defaultMountPoint = URL(filePath: "/sys/fs/cgroup")
+public struct Cgroup2Manager: Sendable {
+    public static let defaultMountPoint = URL(filePath: "/sys/fs/cgroup")
 
     private static let killFile = "cgroup.kill"
     private static let procsFile = "cgroup.procs"
@@ -66,7 +66,7 @@ package struct Cgroup2Manager: Sendable {
         self.logger = logger
     }
 
-    package static func load(
+    public static func load(
         mountPoint: URL = Self.defaultMountPoint,
         group: URL,
         logger: Logger? = nil
@@ -183,7 +183,7 @@ package struct Cgroup2Manager: Sendable {
         }
     }
 
-    package func addProcess(pid: Int32) throws {
+    public func addProcess(pid: Int32) throws {
         self.logger?.debug(
             "adding new proc to cgroup",
             metadata: [
@@ -199,7 +199,7 @@ package struct Cgroup2Manager: Sendable {
         )
     }
 
-    package func applyResources(resources: ContainerizationOCI.LinuxResources) throws {
+    public func applyResources(resources: ContainerizationOCI.LinuxResources) throws {
         self.logger?.debug(
             "applying cgroup resources",
             metadata: [

vminitd/Sources/LCShim/include/syscall.h

@@ -22,7 +22,9 @@
 #define __SYSCALL_H
 
 #include <sys/types.h>
+#ifdef __linux__
 #include <sys/vfs.h>
+#endif
 
 // CLONE_* flags
 #ifndef CLONE_NEWNS

vminitd/Sources/LCShim/syscall.c

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#ifdef __linux__
 #include <sys/prctl.h>
 #include <sys/resource.h>
 #include <sys/syscall.h>
@@ -48,3 +49,4 @@ int CZ_setrlimit(int resource, unsigned long long soft,
   limit.rlim_max = (rlim_t)hard;
   return setrlimit(resource, &limit);
 }
+#endif

vminitd/Sources/VminitdCore/AgentCommand.swift

@@ -14,6 +14,8 @@
 // limitations under the License.
 //===----------------------------------------------------------------------===//
 
+#if os(Linux)
+
 import ArgumentParser
 import CVersion
 import Cgroup
@@ -44,7 +46,7 @@ public struct AgentCommand: AsyncParsableCommand {
     private static let foregroundEnvVar = "FOREGROUND"
     public static let vsockPort = 1024
 
-    @OptionGroup public var options: LogLevelOption
+    @OptionGroup var options: LogLevelOption
 
     public init() {}
 
@@ -214,3 +216,5 @@ public struct AgentCommand: AsyncParsableCommand {
         }
     }
 }
+
+#endif

vminitd/Sources/VminitdCore/CommandRunner.swift

@@ -14,6 +14,8 @@
 // limitations under the License.
 //===----------------------------------------------------------------------===//
 
+#if os(Linux)
+
 import ContainerizationOS
 import Foundation
 import Synchronization
@@ -102,3 +104,5 @@ final class ReaperCommandRunner: CommandRunner, Sendable {
         }
     }
 }
+
+#endif

vminitd/Sources/VminitdCore/ContainerProcess.swift

@@ -14,6 +14,8 @@
 // limitations under the License.
 //===----------------------------------------------------------------------===//
 
+#if os(Linux)
+
 import ContainerizationOS
 import Foundation
 
@@ -64,3 +66,5 @@ protocol ContainerProcess: Sendable {
     /// Set the exit status of the process.
     func setExit(_ status: Int32)
 }
+
+#endif

vminitd/Sources/VminitdCore/HostStdio.swift

@@ -14,9 +14,13 @@
 // limitations under the License.
 //===----------------------------------------------------------------------===//
 
+#if os(Linux)
+
 struct HostStdio: Sendable {
     let stdin: UInt32?
     let stdout: UInt32?
     let stderr: UInt32?
     let terminal: Bool
 }
+
+#endif