chore: apply some clippy lints

Author: nyurik

Cargo.toml

@@ -142,3 +142,19 @@ members = [
     "ctest-test",
     "libc-test",
 ]
+
+# FIXME(msrv): These should be renamed as `[workspace.lints.*]` once MSRV is above 1.64
+#       This way all crates can use it with `[lints] workspace=true` section
+
+[lints.rust]
+# FIXME(cleanup): should be cleaned up
+unused_qualifications = "allow"  # make ident usage consistent in each file
+unused_imports = "allow"
+
+[lints.clippy]
+identity_op = "allow"  # some expressions like `0 | x` are clearer for bit ops
+missing_safety_doc = "allow"  # safety? in libc? seriously?
+
+# FIXME(clippy): all these should probably be fixed
+non_minimal_cfg = "allow"  # for some reason cfg_if! sometimes trigger this
+unnecessary_cast = "allow"  # some casts like `as usize` are only needed for some targets

build.rs

@@ -4,7 +4,7 @@ use std::{env, str};
 // List of cfgs this build script is allowed to set. The list is needed to support check-cfg, as we
 // need to know all the possible cfgs that this script will set. If you need to set another cfg
 // make sure to add it to this list as well.
-const ALLOWED_CFGS: &'static [&'static str] = &[
+const ALLOWED_CFGS: &[&str] = &[
     "emscripten_old_stat_abi",
     "espidf_time32",
     "freebsd10",
@@ -24,7 +24,7 @@ const ALLOWED_CFGS: &'static [&'static str] = &[
 ];
 
 // Extra values to allow for check-cfg.
-const CHECK_CFG_EXTRA: &'static [(&'static str, &'static [&'static str])] = &[
+const CHECK_CFG_EXTRA: &[(&str, &[&str])] = &[
     (
         "target_os",
         &[
@@ -46,7 +46,6 @@ fn main() {
     println!("cargo:rerun-if-changed=build.rs");
 
     let (rustc_minor_ver, _is_nightly) = rustc_minor_nightly();
-    let rustc_dep_of_std = env::var("CARGO_FEATURE_RUSTC_DEP_OF_STD").is_ok();
     let libc_ci = env::var("LIBC_CI").is_ok();
     let target_env = env::var("CARGO_CFG_TARGET_ENV").unwrap_or_default();
     let target_os = env::var("CARGO_CFG_TARGET_OS").unwrap_or_default();
@@ -66,10 +65,8 @@ fn main() {
         vers
     } else if libc_ci {
         which_freebsd().unwrap_or(12)
-    } else if rustc_dep_of_std {
-        12
     } else {
-        12
+        12 // regardless of CARGO_FEATURE_RUSTC_DEP_OF_STD env var
     };
 
     match which_freebsd {

src/fuchsia/mod.rs

@@ -3429,9 +3429,9 @@ f! {
 
     pub fn CMSG_NXTHDR(mhdr: *const msghdr, cmsg: *const cmsghdr) -> *mut cmsghdr {
         if ((*cmsg).cmsg_len as size_t) < mem::size_of::<cmsghdr>() {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         } else if __CMSG_NEXT(cmsg).add(mem::size_of::<cmsghdr>()) >= __MHDR_END(mhdr) {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         } else {
             __CMSG_NEXT(cmsg).cast()
         }
@@ -3441,7 +3441,7 @@ f! {
         if (*mhdr).msg_controllen as size_t >= mem::size_of::<cmsghdr>() {
             (*mhdr).msg_control.cast()
         } else {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         }
     }
 

src/unix/aix/mod.rs

@@ -2441,7 +2441,7 @@ f! {
         if (*mhdr).msg_controllen as usize >= mem::size_of::<cmsghdr>() {
             (*mhdr).msg_control as *mut cmsghdr
         } else {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         }
     }
 
@@ -2452,7 +2452,7 @@ f! {
             if (cmsg as usize + (*cmsg).cmsg_len as usize + mem::size_of::<cmsghdr>())
                 > ((*mhdr).msg_control as usize + (*mhdr).msg_controllen as usize)
             {
-                0 as *mut cmsghdr
+                core::ptr::null_mut::<cmsghdr>()
             } else {
                 // AIX does not have any alignment/padding for ancillary data, so we don't need _CMSG_ALIGN here.
                 (cmsg as usize + (*cmsg).cmsg_len as usize) as *mut cmsghdr

src/unix/bsd/apple/mod.rs

@@ -5463,7 +5463,7 @@ pub const VMADDR_PORT_ANY: c_uint = 0xFFFFFFFF;
 
 const fn __DARWIN_ALIGN32(p: usize) -> usize {
     const __DARWIN_ALIGNBYTES32: usize = mem::size_of::<u32>() - 1;
-    p + __DARWIN_ALIGNBYTES32 & !__DARWIN_ALIGNBYTES32
+    (p + __DARWIN_ALIGNBYTES32) & !__DARWIN_ALIGNBYTES32
 }
 
 pub const THREAD_EXTENDED_POLICY_COUNT: mach_msg_type_number_t =

src/unix/bsd/freebsdlike/dragonfly/mod.rs

@@ -1560,7 +1560,7 @@ f! {
         if next <= max {
             (cmsg as usize + _CMSG_ALIGN((*cmsg).cmsg_len as usize)) as *mut cmsghdr
         } else {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         }
     }
 

src/unix/bsd/freebsdlike/freebsd/mod.rs

@@ -4906,7 +4906,7 @@ const_fn! {
 
 f! {
     pub fn CMSG_DATA(cmsg: *const cmsghdr) -> *mut c_uchar {
-        (cmsg as *mut c_uchar).offset(_ALIGN(mem::size_of::<cmsghdr>()) as isize)
+        (cmsg as *mut c_uchar).add(_ALIGN(mem::size_of::<cmsghdr>()))
     }
 
     pub {const} fn CMSG_LEN(length: c_uint) -> c_uint {
@@ -4921,7 +4921,7 @@ f! {
             cmsg as usize + _ALIGN((*cmsg).cmsg_len as usize) + _ALIGN(mem::size_of::<cmsghdr>());
         let max = (*mhdr).msg_control as usize + (*mhdr).msg_controllen as usize;
         if next > max {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         } else {
             (cmsg as usize + _ALIGN((*cmsg).cmsg_len as usize)) as *mut cmsghdr
         }
@@ -4968,14 +4968,12 @@ f! {
         let bitset_bits = 8 * mem::size_of::<c_long>();
         let (idx, offset) = (cpu / bitset_bits, cpu % bitset_bits);
         cpuset.__bits[idx] |= 1 << offset;
-        ()
     }
 
     pub fn CPU_CLR(cpu: usize, cpuset: &mut cpuset_t) -> () {
         let bitset_bits = 8 * mem::size_of::<c_long>();
         let (idx, offset) = (cpu / bitset_bits, cpu % bitset_bits);
         cpuset.__bits[idx] &= !(1 << offset);
-        ()
     }
 
     pub fn CPU_ISSET(cpu: usize, cpuset: &cpuset_t) -> bool {

src/unix/bsd/netbsdlike/netbsd/mod.rs

@@ -2423,7 +2423,7 @@ const_fn! {
 
 f! {
     pub fn CMSG_DATA(cmsg: *const cmsghdr) -> *mut c_uchar {
-        (cmsg as *mut c_uchar).offset(_ALIGN(mem::size_of::<cmsghdr>()) as isize)
+        (cmsg as *mut c_uchar).add(_ALIGN(mem::size_of::<cmsghdr>()))
     }
 
     pub {const} fn CMSG_LEN(length: c_uint) -> c_uint {
@@ -2438,7 +2438,7 @@ f! {
             cmsg as usize + _ALIGN((*cmsg).cmsg_len as usize) + _ALIGN(mem::size_of::<cmsghdr>());
         let max = (*mhdr).msg_control as usize + (*mhdr).msg_controllen as usize;
         if next > max {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         } else {
             (cmsg as usize + _ALIGN((*cmsg).cmsg_len as usize)) as *mut cmsghdr
         }

src/unix/bsd/netbsdlike/openbsd/mod.rs

@@ -1940,7 +1940,7 @@ f! {
             cmsg as usize + _ALIGN((*cmsg).cmsg_len as usize) + _ALIGN(mem::size_of::<cmsghdr>());
         let max = (*mhdr).msg_control as usize + (*mhdr).msg_controllen as usize;
         if next > max {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         } else {
             (cmsg as usize + _ALIGN((*cmsg).cmsg_len as usize)) as *mut cmsghdr
         }

src/unix/haiku/mod.rs

@@ -1570,7 +1570,7 @@ f! {
         if (*mhdr).msg_controllen as usize >= mem::size_of::<cmsghdr>() {
             (*mhdr).msg_control as *mut cmsghdr
         } else {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         }
     }
 
@@ -1595,7 +1595,7 @@ f! {
             + CMSG_ALIGN(mem::size_of::<cmsghdr>());
         let max = (*mhdr).msg_control as usize + (*mhdr).msg_controllen as usize;
         if next > max {
-            0 as *mut cmsghdr
+            core::ptr::null_mut::<cmsghdr>()
         } else {
             (cmsg as usize + CMSG_ALIGN((*cmsg).cmsg_len as usize)) as *mut cmsghdr
         }