Remove libc dependencies (#284)

Author: Tacha-S

rclrs/Cargo.toml

@@ -14,8 +14,6 @@ path = "src/lib.rs"
 # Please keep the list of dependencies alphabetically sorted,
 # and also state why each dependency is needed.
 [dependencies]
-# Needed for FFI
-libc = "0.2.43"
 # Needed for the Message trait, among others
 rosidl_runtime_rs = "0.3"
 # Needed for clients

rclrs/src/arguments.rs

@@ -1,9 +1,8 @@
 use std::ffi::CString;
 use std::os::raw::c_char;
+use std::os::raw::c_void;
 use std::ptr::null_mut;
 
-use libc::c_void;
-
 use crate::error::*;
 use crate::rcl_bindings::*;
 

rclrs/src/node.rs

@@ -3,10 +3,10 @@ mod graph;
 use std::cmp::PartialEq;
 use std::ffi::CStr;
 use std::fmt;
+use std::os::raw::c_char;
 use std::sync::{Arc, Mutex, Weak};
 use std::vec::Vec;
 
-use libc::c_char;
 use rosidl_runtime_rs::Message;
 
 pub use self::builder::*;

rclrs/src/parameter/override_map.rs

@@ -1,7 +1,6 @@
 use std::collections::BTreeMap;
 use std::ffi::CStr;
-
-use libc::c_char;
+use std::os::raw::c_char;
 
 use crate::rcl_bindings::*;
 use crate::{ParameterValue, RclrsError, ToResult};

rosidl_generator_rs/resource/Cargo.toml.em

@@ -4,7 +4,6 @@ version = "@(package_version)"
 edition = "2021"
 
 [dependencies]
-libc = "0.2"
 rosidl_runtime_rs = "0.3"
 serde = { version = "1", optional = true, features = ["derive"] }
 @[for dep in dependency_packages]@

rosidl_generator_rs/resource/msg_rmw.rs.em

@@ -19,14 +19,15 @@ type_name = msg_spec.structure.namespaced_type.name
 
 #[link(name = "@(package_name)__rosidl_typesupport_c")]
 extern "C" {
-    fn rosidl_typesupport_c__get_message_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() -> libc::uintptr_t;
+    fn rosidl_typesupport_c__get_message_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() -> *const std::os::raw::c_void;
 }
 
 #[link(name = "@(package_name)__rosidl_generator_c")]
 extern "C" {
     fn @(package_name)__@(subfolder)__@(type_name)__init(msg: *mut @(type_name)) -> bool;
-    fn @(package_name)__@(subfolder)__@(type_name)__Sequence__init(seq: *mut rosidl_runtime_rs::Sequence<@(type_name)>, size: libc::size_t) -> bool;
+    fn @(package_name)__@(subfolder)__@(type_name)__Sequence__init(seq: *mut rosidl_runtime_rs::Sequence<@(type_name)>, size: usize) -> bool;
     fn @(package_name)__@(subfolder)__@(type_name)__Sequence__fini(seq: *mut rosidl_runtime_rs::Sequence<@(type_name)>);
+    fn @(package_name)__@(subfolder)__@(type_name)__Sequence__copy(in_seq: &rosidl_runtime_rs::Sequence<@(type_name)>, out_seq: *mut rosidl_runtime_rs::Sequence<@(type_name)>) -> bool;
 }
 
 @# Drop is not needed, since the default drop glue does the same as fini here:
@@ -80,18 +81,17 @@ impl Default for @(type_name) {
 }
 
 impl rosidl_runtime_rs::SequenceAlloc for @(type_name) {
-  fn sequence_init(seq: &mut rosidl_runtime_rs::Sequence<Self>, size: libc::size_t) -> bool {
-    // SAFETY: This is safe since a the point is guaranteed to be valid/initialized.
+  fn sequence_init(seq: &mut rosidl_runtime_rs::Sequence<Self>, size: usize) -> bool {
+    // SAFETY: This is safe since the pointer is guaranteed to be valid/initialized.
     unsafe { @(package_name)__@(subfolder)__@(type_name)__Sequence__init(seq as *mut _, size) }
   }
   fn sequence_fini(seq: &mut rosidl_runtime_rs::Sequence<Self>) {
-    // SAFETY: This is safe since a the point is guaranteed to be valid/initialized.
+    // SAFETY: This is safe since the pointer is guaranteed to be valid/initialized.
     unsafe { @(package_name)__@(subfolder)__@(type_name)__Sequence__fini(seq as *mut _) }
   }
   fn sequence_copy(in_seq: &rosidl_runtime_rs::Sequence<Self>, out_seq: &mut rosidl_runtime_rs::Sequence<Self>) -> bool {
-      out_seq.resize_to_at_least(in_seq.len());
-      out_seq.clone_from_slice(in_seq.as_slice());
-      true
+    // SAFETY: This is safe since the pointer is guaranteed to be valid/initialized.
+    unsafe { @(package_name)__@(subfolder)__@(type_name)__Sequence__copy(in_seq, out_seq as *mut _) }
   }
 }
 
@@ -103,7 +103,7 @@ impl rosidl_runtime_rs::Message for @(type_name) {
 
 impl rosidl_runtime_rs::RmwMessage for @(type_name) where Self: Sized {
   const TYPE_NAME: &'static str = "@(package_name)/@(subfolder)/@(type_name)";
-  fn get_type_support() -> libc::uintptr_t {
+  fn get_type_support() -> *const std::os::raw::c_void {
     // SAFETY: No preconditions for this function.
     unsafe { rosidl_typesupport_c__get_message_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() }
   }

rosidl_generator_rs/resource/srv.rs.em

@@ -24,7 +24,7 @@ type_name = srv_spec.namespaced_type.name
 
 #[link(name = "@(package_name)__rosidl_typesupport_c")]
 extern "C" {
-    fn rosidl_typesupport_c__get_service_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() -> libc::uintptr_t;
+    fn rosidl_typesupport_c__get_service_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() -> *const std::os::raw::c_void;
 }
 
 // Corresponds to @(package_name)__@(subfolder)__@(type_name)
@@ -34,7 +34,7 @@ impl rosidl_runtime_rs::Service for @(type_name) {
   type Request = crate::@(subfolder)::@(type_name)_Request;
   type Response = crate::@(subfolder)::@(type_name)_Response;
 
-  fn get_type_support() -> libc::uintptr_t {
+  fn get_type_support() -> *const std::os::raw::c_void {
     // SAFETY: No preconditions for this function.
     unsafe { rosidl_typesupport_c__get_service_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() }
   }
@@ -61,7 +61,7 @@ type_name = srv_spec.namespaced_type.name
 
   #[link(name = "@(package_name)__rosidl_typesupport_c")]
   extern "C" {
-      fn rosidl_typesupport_c__get_service_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() -> libc::uintptr_t;
+      fn rosidl_typesupport_c__get_service_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() -> *const std::os::raw::c_void;
   }
 
   // Corresponds to @(package_name)__@(subfolder)__@(type_name)
@@ -71,7 +71,7 @@ type_name = srv_spec.namespaced_type.name
     type Request = crate::@(subfolder)::rmw::@(type_name)_Request;
     type Response = crate::@(subfolder)::rmw::@(type_name)_Response;
 
-    fn get_type_support() -> libc::uintptr_t {
+    fn get_type_support() -> *const std::os::raw::c_void {
       // SAFETY: No preconditions for this function.
       unsafe { rosidl_typesupport_c__get_service_type_support_handle__@(package_name)__@(subfolder)__@(type_name)() }
     }

rosidl_runtime_rs/Cargo.toml

@@ -13,8 +13,6 @@ path = "src/lib.rs"
 # Please keep the list of dependencies alphabetically sorted,
 # and also state why each dependency is needed.
 [dependencies]
-# Needed for FFI
-libc = "0.2"
 # Optional dependency for making it possible to convert messages to and from
 # formats such as JSON, YAML, Pickle, etc.
 serde = { version = "1", optional = true }
@@ -24,4 +22,3 @@ serde = { version = "1", optional = true }
 quickcheck = "1"
 # Needed for testing serde support
 serde_json = "1"
-

rosidl_runtime_rs/src/sequence.rs

@@ -37,8 +37,8 @@ use crate::traits::SequenceAlloc;
 #[repr(C)]
 pub struct Sequence<T: SequenceAlloc> {
     data: *mut T,
-    size: libc::size_t,
-    capacity: libc::size_t,
+    size: usize,
+    capacity: usize,
 }
 
 /// A bounded sequence.
@@ -274,30 +274,6 @@ where
     }
 }
 
-impl<T: Default + SequenceAlloc> Sequence<T> {
-    /// Internal function for the sequence_copy impl. To be removed when rosidl#650 is backported and released.
-    pub fn resize_to_at_least(&mut self, len: usize) {
-        let allocation_size = std::mem::size_of::<Self>() * len;
-        if self.capacity < len {
-            // SAFETY: The memory in self.data is owned by C.
-            let data = unsafe { libc::realloc(self.data as *mut _, allocation_size) } as *mut T;
-            if data.is_null() {
-                panic!("realloc failed");
-            }
-            // Initialize the new memory
-            for i in self.capacity..len {
-                // SAFETY: i is in bounds, and write() is appropriate for initializing uninitialized memory
-                unsafe {
-                    data.add(i).write(T::default());
-                }
-            }
-            self.data = data;
-            self.size = len;
-            self.capacity = len;
-        }
-    }
-}
-
 // ========================= impl for BoundedSequence =========================
 
 impl<T: Debug + SequenceAlloc, const N: usize> Debug for BoundedSequence<T, N> {
@@ -518,12 +494,16 @@ macro_rules! impl_sequence_alloc_for_primitive_type {
     ($rust_type:ty, $init_func:ident, $fini_func:ident, $copy_func:ident) => {
         #[link(name = "rosidl_runtime_c")]
         extern "C" {
-            fn $init_func(seq: *mut Sequence<$rust_type>, size: libc::size_t) -> bool;
+            fn $init_func(seq: *mut Sequence<$rust_type>, size: usize) -> bool;
             fn $fini_func(seq: *mut Sequence<$rust_type>);
+            fn $copy_func(
+                in_seq: *const Sequence<$rust_type>,
+                out_seq: *mut Sequence<$rust_type>,
+            ) -> bool;
         }
 
         impl SequenceAlloc for $rust_type {
-            fn sequence_init(seq: &mut Sequence<Self>, size: libc::size_t) -> bool {
+            fn sequence_init(seq: &mut Sequence<Self>, size: usize) -> bool {
                 // SAFETY: There are no special preconditions to the sequence_init function.
                 unsafe {
                     // This allocates space and sets seq.size and seq.capacity to size
@@ -538,26 +518,8 @@ macro_rules! impl_sequence_alloc_for_primitive_type {
                 unsafe { $fini_func(seq as *mut _) }
             }
             fn sequence_copy(in_seq: &Sequence<Self>, out_seq: &mut Sequence<Self>) -> bool {
-                let allocation_size = std::mem::size_of::<Self>() * in_seq.size;
-                if out_seq.capacity < in_seq.size {
-                    // SAFETY: The memory in out_seq.data is owned by C.
-                    let data = unsafe { libc::realloc(out_seq.data as *mut _, allocation_size) };
-                    if data.is_null() {
-                        return false;
-                    }
-                    out_seq.data = data as *mut _;
-                    out_seq.capacity = in_seq.size;
-                }
-                // SAFETY: The memory areas don't overlap.
-                unsafe {
-                    libc::memcpy(
-                        out_seq.data as *mut _,
-                        in_seq.data as *const _,
-                        allocation_size,
-                    );
-                }
-                out_seq.size = in_seq.size;
-                true
+                // SAFETY: There are no special preconditions to the sequence_copy function.
+                unsafe { $copy_func(in_seq as *const _, out_seq as *mut _) }
             }
         }
     };

rosidl_runtime_rs/src/string.rs

@@ -29,9 +29,9 @@ use crate::traits::SequenceAlloc;
 pub struct String {
     /// Dynamic memory in this type is allocated and deallocated by C, but this is a detail that is managed by
     /// the relevant functions and trait impls.
-    data: *mut libc::c_char,
-    size: libc::size_t,
-    capacity: libc::size_t,
+    data: *mut std::os::raw::c_char,
+    size: usize,
+    capacity: usize,
 }
 
 /// A zero-terminated string of 16-bit characters.
@@ -50,9 +50,9 @@ pub struct String {
 /// ```
 #[repr(C)]
 pub struct WString {
-    data: *mut libc::c_ushort,
-    size: libc::size_t,
-    capacity: libc::size_t,
+    data: *mut std::os::raw::c_ushort,
+    size: usize,
+    capacity: usize,
 }
 
 /// A zero-terminated string of 8-bit characters with a length limit.
@@ -117,9 +117,13 @@ macro_rules! string_impl {
         extern "C" {
             fn $init(s: *mut $string) -> bool;
             fn $fini(s: *mut $string);
-            fn $assignn(s: *mut $string, value: *const $char_type, n: libc::size_t) -> bool;
-            fn $sequence_init(seq: *mut Sequence<$string>, size: libc::size_t) -> bool;
+            fn $assignn(s: *mut $string, value: *const $char_type, n: usize) -> bool;
+            fn $sequence_init(seq: *mut Sequence<$string>, size: usize) -> bool;
             fn $sequence_fini(seq: *mut Sequence<$string>);
+            fn $sequence_copy(
+                in_seq: *const Sequence<$string>,
+                out_seq: *mut Sequence<$string>,
+            ) -> bool;
         }
 
         impl Default for $string {
@@ -226,7 +230,7 @@ macro_rules! string_impl {
         unsafe impl Sync for $string {}
 
         impl SequenceAlloc for $string {
-            fn sequence_init(seq: &mut Sequence<Self>, size: libc::size_t) -> bool {
+            fn sequence_init(seq: &mut Sequence<Self>, size: usize) -> bool {
                 // SAFETY: There are no special preconditions to the sequence_init function.
                 unsafe { $sequence_init(seq as *mut _, size) }
             }
@@ -235,17 +239,16 @@ macro_rules! string_impl {
                 unsafe { $sequence_fini(seq as *mut _) }
             }
             fn sequence_copy(in_seq: &Sequence<Self>, out_seq: &mut Sequence<Self>) -> bool {
-                out_seq.resize_to_at_least(in_seq.len());
-                out_seq.clone_from_slice(in_seq.as_slice());
-                true
+                // SAFETY: There are no special preconditions to the sequence_copy function.
+                unsafe { $sequence_copy(in_seq as *const _, out_seq as *mut _) }
             }
         }
     };
 }
 
 string_impl!(
     String,
-    libc::c_char,
+    std::os::raw::c_char,
     u8,
     from_utf8_lossy,
     rosidl_runtime_c__String__init,
@@ -257,7 +260,7 @@ string_impl!(
 );
 string_impl!(
     WString,
-    libc::c_ushort,
+    std::os::raw::c_ushort,
     u16,
     from_utf16_lossy,
     rosidl_runtime_c__U16String__init,
@@ -330,7 +333,7 @@ impl<const N: usize> Debug for BoundedString<N> {
 }
 
 impl<const N: usize> Deref for BoundedString<N> {
-    type Target = [libc::c_char];
+    type Target = [std::os::raw::c_char];
     fn deref(&self) -> &Self::Target {
         self.inner.deref()
     }
@@ -349,7 +352,7 @@ impl<const N: usize> Display for BoundedString<N> {
 }
 
 impl<const N: usize> SequenceAlloc for BoundedString<N> {
-    fn sequence_init(seq: &mut Sequence<Self>, size: libc::size_t) -> bool {
+    fn sequence_init(seq: &mut Sequence<Self>, size: usize) -> bool {
         // SAFETY: There are no special preconditions to the rosidl_runtime_c__String__Sequence__init function.
         unsafe {
             rosidl_runtime_c__String__Sequence__init(seq as *mut Sequence<Self> as *mut _, size)
@@ -415,7 +418,7 @@ impl<const N: usize> Display for BoundedWString<N> {
 }
 
 impl<const N: usize> SequenceAlloc for BoundedWString<N> {
-    fn sequence_init(seq: &mut Sequence<Self>, size: libc::size_t) -> bool {
+    fn sequence_init(seq: &mut Sequence<Self>, size: usize) -> bool {
         // SAFETY: There are no special preconditions to the rosidl_runtime_c__U16String__Sequence__init function.
         unsafe {
             rosidl_runtime_c__U16String__Sequence__init(seq as *mut Sequence<Self> as *mut _, size)

rosidl_runtime_rs/src/traits.rs

@@ -24,7 +24,7 @@ use std::fmt::Debug;
 /// User code never needs to call these trait methods, much less implement this trait.
 pub trait SequenceAlloc: Sized {
     /// Wraps the corresponding init function generated by `rosidl_generator_c`.
-    fn sequence_init(seq: &mut crate::Sequence<Self>, size: libc::size_t) -> bool;
+    fn sequence_init(seq: &mut crate::Sequence<Self>, size: usize) -> bool;
     /// Wraps the corresponding fini function generated by `rosidl_generator_c`.
     fn sequence_fini(seq: &mut crate::Sequence<Self>);
     /// Wraps the corresponding copy function generated by `rosidl_generator_c`.
@@ -42,7 +42,7 @@ pub trait RmwMessage: Clone + Debug + Default + Send + Sync + Message {
     const TYPE_NAME: &'static str;
 
     /// Get a pointer to the correct `rosidl_message_type_support_t` structure.
-    fn get_type_support() -> libc::uintptr_t;
+    fn get_type_support() -> *const std::os::raw::c_void;
 }
 
 /// Trait for types that can be used in a `rclrs::Subscription` and a `rclrs::Publisher`.
@@ -158,5 +158,5 @@ pub trait Service: 'static {
     type Response: Message;
 
     /// Get a pointer to the correct `rosidl_service_type_support_t` structure.
-    fn get_type_support() -> libc::uintptr_t;
+    fn get_type_support() -> *const std::os::raw::c_void;
 }