Fix all warnings from the compiler

This change simply fixes all the warnings from the latest version of the
compiler. It also removes the (non-test code) unsafe blocks. One of the
warnings I think was actually a bug - a cgroup builder could fail to
apply resource constraints but still return a Cgroup silently. Now a
builder will return an Error correctly in this case - this is an API
change though so requires a mv bump.

Author: campbellC

Cargo.toml

@@ -5,7 +5,7 @@ repository = "https://github.com/levex/cgroups-rs"
 keywords = ["linux", "cgroup", "containers", "isolation"]
 categories = ["os", "api-bindings", "os::unix-apis"]
 license = "MIT OR Apache-2.0"
-version = "0.1.1-alpha.0"
+version = "0.2.1-alpha.0"
 authors = ["Levente Kurusa <[email protected]>", "Sam Wilson <[email protected]>"]
 edition = "2018"
 

src/blkio.rs

@@ -6,8 +6,8 @@ use std::fs::File;
 use std::io::{Read, Write};
 use std::path::PathBuf;
 
-use crate::error::*;
 use crate::error::ErrorKind::*;
+use crate::error::*;
 
 use crate::{
     BlkIoResources, ControllIdentifier, ControllerInternal, Controllers, Resources, Subsystem,
@@ -279,7 +279,8 @@ impl ControllerInternal for BlkIoController {
 
             for dev in &res.weight_device {
                 let _ = self.set_weight_for_device(dev.major, dev.minor, dev.weight as u64);
-                let _ = self.set_leaf_weight_for_device(dev.major, dev.minor, dev.leaf_weight as u64);
+                let _ =
+                    self.set_leaf_weight_for_device(dev.major, dev.minor, dev.leaf_weight as u64);
             }
 
             for dev in &res.throttle_read_bps_device {
@@ -309,19 +310,7 @@ impl ControllIdentifier for BlkIoController {
     }
 }
 
-impl<'a> From<&'a Subsystem> for &'a BlkIoController {
-    fn from(sub: &'a Subsystem) -> &'a BlkIoController {
-        unsafe {
-            match sub {
-                Subsystem::BlkIo(c) => c,
-                _ => {
-                    assert_eq!(1, 0);
-                    ::std::mem::uninitialized()
-                }
-            }
-        }
-    }
-}
+impl_from_subsystem_for_controller!(Subsystem::BlkIo, BlkIoController);
 
 fn read_string_from(mut file: File) -> Result<String> {
     let mut string = String::new();
@@ -334,7 +323,10 @@ fn read_string_from(mut file: File) -> Result<String> {
 fn read_u64_from(mut file: File) -> Result<u64> {
     let mut string = String::new();
     match file.read_to_string(&mut string) {
-        Ok(_) => string.trim().parse().map_err(|e| Error::with_cause(ParseError, e)),
+        Ok(_) => string
+            .trim()
+            .parse()
+            .map_err(|e| Error::with_cause(ParseError, e)),
         Err(e) => Err(Error::with_cause(ReadFailed, e)),
     }
 }
@@ -588,12 +580,7 @@ impl BlkIoController {
     }
 
     /// Same as `set_leaf_weight()`, but settable per each block device.
-    pub fn set_leaf_weight_for_device(
-        &self,
-        major: u64,
-        minor: u64,
-        weight: u64,
-    ) -> Result<()> {
+    pub fn set_leaf_weight_for_device(&self, major: u64, minor: u64, weight: u64) -> Result<()> {
         self.open_path("blkio.leaf_weight_device", true)
             .and_then(|mut file| {
                 file.write_all(format!("{}:{} {}", major, minor, weight).as_ref())
@@ -612,12 +599,7 @@ impl BlkIoController {
 
     /// Throttle the bytes per second rate of read operation affecting the block device
     /// `major:minor` to `bps`.
-    pub fn throttle_read_bps_for_device(
-        &self,
-        major: u64,
-        minor: u64,
-        bps: u64,
-    ) -> Result<()> {
+    pub fn throttle_read_bps_for_device(&self, major: u64, minor: u64, bps: u64) -> Result<()> {
         self.open_path("blkio.throttle.read_bps_device", true)
             .and_then(|mut file| {
                 file.write_all(format!("{}:{} {}", major, minor, bps).to_string().as_ref())
@@ -627,12 +609,7 @@ impl BlkIoController {
 
     /// Throttle the I/O operations per second rate of read operation affecting the block device
     /// `major:minor` to `bps`.
-    pub fn throttle_read_iops_for_device(
-        &self,
-        major: u64,
-        minor: u64,
-        iops: u64,
-    ) -> Result<()> {
+    pub fn throttle_read_iops_for_device(&self, major: u64, minor: u64, iops: u64) -> Result<()> {
         self.open_path("blkio.throttle.read_iops_device", true)
             .and_then(|mut file| {
                 file.write_all(format!("{}:{} {}", major, minor, iops).to_string().as_ref())
@@ -641,12 +618,7 @@ impl BlkIoController {
     }
     /// Throttle the bytes per second rate of write operation affecting the block device
     /// `major:minor` to `bps`.
-    pub fn throttle_write_bps_for_device(
-        &self,
-        major: u64,
-        minor: u64,
-        bps: u64,
-    ) -> Result<()> {
+    pub fn throttle_write_bps_for_device(&self, major: u64, minor: u64, bps: u64) -> Result<()> {
         self.open_path("blkio.throttle.write_bps_device", true)
             .and_then(|mut file| {
                 file.write_all(format!("{}:{} {}", major, minor, bps).to_string().as_ref())
@@ -656,12 +628,7 @@ impl BlkIoController {
 
     /// Throttle the I/O operations per second rate of write operation affecting the block device
     /// `major:minor` to `bps`.
-    pub fn throttle_write_iops_for_device(
-        &self,
-        major: u64,
-        minor: u64,
-        iops: u64,
-    ) -> Result<()> {
+    pub fn throttle_write_iops_for_device(&self, major: u64, minor: u64, iops: u64) -> Result<()> {
         self.open_path("blkio.throttle.write_iops_device", true)
             .and_then(|mut file| {
                 file.write_all(format!("{}:{} {}", major, minor, iops).to_string().as_ref())
@@ -671,20 +638,14 @@ impl BlkIoController {
 
     /// Set the weight of the control group's tasks.
     pub fn set_weight(&self, w: u64) -> Result<()> {
-        self.open_path("blkio.weight", true)
-            .and_then(|mut file| {
-                file.write_all(w.to_string().as_ref())
-                    .map_err(|e| Error::with_cause(WriteFailed, e))
-            })
+        self.open_path("blkio.weight", true).and_then(|mut file| {
+            file.write_all(w.to_string().as_ref())
+                .map_err(|e| Error::with_cause(WriteFailed, e))
+        })
     }
 
     /// Same as `set_weight()`, but settable per each block device.
-    pub fn set_weight_for_device(
-        &self,
-        major: u64,
-        minor: u64,
-        weight: u64,
-    ) -> Result<()> {
+    pub fn set_weight_for_device(&self, major: u64, minor: u64, weight: u64) -> Result<()> {
         self.open_path("blkio.weight_device", true)
             .and_then(|mut file| {
                 file.write_all(format!("{}:{} {}", major, minor, weight).as_ref())
@@ -755,10 +716,7 @@ Total 61823067136
     #[test]
     fn test_parse_io_service_total() {
         let ok = parse_io_service_total(TEST_VALUE.to_string()).unwrap();
-        assert_eq!(
-            ok,
-            61823067136
-        );
+        assert_eq!(ok, 61823067136);
     }
 
     #[test]
@@ -806,10 +764,7 @@ Total 61823067136
             ]
         );
         let err = parse_io_service(TEST_WRONG_VALUE.to_string()).unwrap_err();
-        assert_eq!(
-            err.kind(),
-            &ErrorKind::ParseError,
-        );
+        assert_eq!(err.kind(), &ErrorKind::ParseError,);
     }
 
     #[test]

src/cgroup.rs

@@ -24,7 +24,7 @@ pub struct Cgroup<'b> {
     subsystems: Vec<Subsystem>,
 
     /// The hierarchy.
-    hier: &'b Hierarchy,
+    hier: &'b dyn Hierarchy,
 }
 
 impl<'b> Cgroup<'b> {
@@ -41,7 +41,7 @@ impl<'b> Cgroup<'b> {
     ///
     /// Note that if the handle goes out of scope and is dropped, the control group is _not_
     /// destroyed.
-    pub fn new<P: AsRef<Path>>(hier: &Hierarchy, path: P) -> Cgroup {
+    pub fn new<P: AsRef<Path>>(hier: &dyn Hierarchy, path: P) -> Cgroup {
         let cg = Cgroup::load(hier, path);
         cg.create();
         cg
@@ -54,7 +54,7 @@ impl<'b> Cgroup<'b> {
     ///
     /// Note that if the handle goes out of scope and is dropped, the control group is _not_
     /// destroyed.
-    pub fn load<P: AsRef<Path>>(hier: &Hierarchy, path: P) -> Cgroup {
+    pub fn load<P: AsRef<Path>>(hier: &dyn Hierarchy, path: P) -> Cgroup {
         let path = path.as_ref();
         let mut subsystems = hier.subsystems();
         if path.as_os_str() != "" {