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src/container/builder.rs

@@ -3,14 +3,16 @@ use std::path::PathBuf;
 
 use super::{init_builder::InitContainerBuilder, tenant_builder::TenantContainerBuilder};
 pub struct ContainerBuilder {
+    /// Id of the container
     pub(super) container_id: String,
-
+    /// Root directory for container state
     pub(super) root_path: PathBuf,
-
+    /// Interface to operating system primitives
     pub(super) syscall: LinuxSyscall,
-
+    /// File which will be used to communicate the pid of the 
+    /// container process to the higher level runtime
     pub(super) pid_file: Option<PathBuf>,
-
+    /// Socket to communicate the file descriptor of the ptty
     pub(super) console_socket: Option<PathBuf>,
 }
 

src/container/builder_impl.rs

@@ -21,18 +21,30 @@ use crate::{
 use super::{Container, ContainerStatus};
 
 pub(super) struct ContainerBuilderImpl {
+    /// Flag indicating if an init or a tenant container should be created
     pub init: bool,
+    /// Interface to operating system primitives
     pub syscall: LinuxSyscall,
+    /// Flag indicating if systemd should be used for cgroup management
     pub use_systemd: bool,
+    /// Id of the container
     pub container_id: String,
-    pub root_path: PathBuf,
+    /// Directory where the state of the container will be stored
     pub container_dir: PathBuf,
+    /// OCI complient runtime spec
     pub spec: Spec,
+    /// Root filesystem of the container
     pub rootfs: PathBuf,
+    /// File which will be used to communicate the pid of the 
+    /// container process to the higher level runtime
     pub pid_file: Option<PathBuf>,
+    /// Socket to communicate the file descriptor of the ptty
     pub console_socket: Option<FileDescriptor>,
+    /// Options for rootless containers
     pub rootless: Option<Rootless>,
+    /// Socket to communicate container start
     pub notify_socket: NotifyListener,
+    /// Container state
     pub container: Option<Container>,
 }
 

src/container/init_builder.rs

@@ -72,7 +72,6 @@ impl InitContainerBuilder {
             init: true,
             syscall: self.base.syscall,
             container_id: self.base.container_id,
-            root_path: self.base.root_path,
             pid_file: self.base.pid_file,
             console_socket: csocketfd,
             use_systemd: self.use_systemd,

src/container/mod.rs

@@ -1,4 +1,9 @@
 //! Container management
+/// This crate is responsible for the creation of containers. It provides a builder that can 
+/// be used to configure and create containers. We distinguish between an init container for which
+/// namespaces and cgroups will be created (usually) and a tenant container process that will move 
+/// into the existing namespaces and cgroups of the initial container process (e.g. used to implement
+/// the exec command). 
 
 pub mod builder;
 mod builder_impl;

src/container/tenant_builder.rs

@@ -113,7 +113,6 @@ impl TenantContainerBuilder {
             init: false,
             syscall: self.base.syscall,
             container_id: self.base.container_id,
-            root_path: self.base.root_path,
             pid_file: self.base.pid_file,
             console_socket: csocketfd,
             use_systemd,