Add optional zerocopy trait derives

Author: joshlf

Cargo.toml

@@ -130,6 +130,7 @@ cargo-args = ["-Zbuild-std=core"]
 
 [dependencies]
 rustc-std-workspace-core = { version = "1.0.0", optional = true }
+zerocopy = { version = "0.7.16", optional = true, features = ["derive"] }
 
 [features]
 default = ["std"]

README.md

@@ -56,6 +56,7 @@ newer Rust features are only available on newer Rust toolchains:
 | `core::ffi::c_void`  |  1.30.0 |
 | `repr(packed(N))`    |  1.33.0 |
 | `cfg(target_vendor)` |  1.33.0 |
+| `zerocopy`           |  1.61.0 |
 | `const-extern-fn`    |  1.62.0 |
 
 ## Platform support

ci/build.sh

@@ -18,6 +18,11 @@ if [ "${TOOLCHAIN}" = "nightly" ] ; then
     rustup component add rust-src
 fi
 
+version_gte() {
+    # Adapted from https://stackoverflow.com/a/4024263/836390
+    [  "$2" = "$(echo -e "$1\n$2" | sort -V | head -n1)" ]
+}
+
 test_target() {
     BUILD_CMD="${1}"
     TARGET="${2}"
@@ -66,15 +71,22 @@ test_target() {
             --target "${TARGET}" --features extra_traits
     fi
 
-    # Test the 'const-extern-fn' feature on nightly
-    if [ "${RUST}" = "nightly" ]; then
+    # Test the 'const-extern-fn' feature on nightly and the 'zerocopy' feature
+    # any version starting with zerocopy's MSRV (1.61.0).
+    if [ "${RUST}" = "nightly" ] || version_gte "${RUST}" "1.61.0"; then
+        if [ "${RUST}" = "nightly" ]; then
+            FEATURES="const-extern-fn,zerocopy"
+        else
+            FEATURES="zerocopy"
+        fi
+
         if [ "${NO_STD}" != "1" ]; then
             cargo "+${RUST}" "${BUILD_CMD}" -vv --no-default-features --target "${TARGET}" \
-                --features const-extern-fn
+                --features "$FEATURES"
         else
             RUSTFLAGS="-A improper_ctypes_definitions" cargo "+${RUST}" "${BUILD_CMD}" \
                 -Z build-std=core,alloc -vv --no-default-features \
-                --target "${TARGET}" --features const-extern-fn
+                --target "${TARGET}" --features "$FEATURES"
         fi
     fi
 

ci/run.sh

@@ -101,7 +101,7 @@ if [ "$TARGET" = "s390x-unknown-linux-gnu" ]; then
         continue
       fi
     elif [ "$passed" = "2" ]; then
-      if cargo test --features extra_traits --manifest-path libc-test/Cargo.toml --target "${TARGET}" ${LIBC_CI_ZBUILD_STD+"-Zbuild-std"}; then
+      if cargo test --features extra_traits,zerocopy --manifest-path libc-test/Cargo.toml --target "${TARGET}" ${LIBC_CI_ZBUILD_STD+"-Zbuild-std"}; then
         break
       fi
     fi
@@ -114,6 +114,6 @@ else
 
   cargo test --manifest-path libc-test/Cargo.toml --target "${TARGET}" ${LIBC_CI_ZBUILD_STD+"-Zbuild-std"}
 
-  RUST_BACKTRACE=1 cargo test --features extra_traits --manifest-path libc-test/Cargo.toml \
+  RUST_BACKTRACE=1 cargo test --features extra_traits,zerocopy --manifest-path libc-test/Cargo.toml \
     --target "${TARGET}" ${LIBC_CI_ZBUILD_STD+"-Zbuild-std"}
 fi

libc-test/Cargo.toml

@@ -25,6 +25,7 @@ default = ["std"]
 std = ["libc/std"]
 align = ["libc/align"]
 extra_traits = ["libc/extra_traits"]
+zerocopy = ["libc/zerocopy"]
 
 [[test]]
 name = "main"

src/lib.rs

@@ -24,6 +24,10 @@
 #![cfg_attr(feature = "rustc-dep-of-std", no_core)]
 #![cfg_attr(libc_const_extern_fn_unstable, feature(const_extern_fn))]
 
+#[cfg(feature = "zerocopy")]
+#[macro_use]
+extern crate zerocopy;
+
 #[macro_use]
 mod macros;
 

src/unix/aix/mod.rs

@@ -71,24 +71,29 @@ e! {
 }
 
 s! {
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct fsid_t {
         pub val: [::c_uint; 2],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct fsid64_t {
         pub val: [::uint64_t; 2],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct timezone {
         pub tz_minuteswest: ::c_int,
         pub tz_dsttime: ::c_int,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct ip_mreq {
         pub imr_multiaddr: in_addr,
         pub imr_interface: in_addr,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct dirent {
         pub d_offset: ::c_ulong,
         pub d_ino: ::ino_t,
@@ -97,6 +102,7 @@ s! {
         pub d_name: [::c_char; 256]
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct termios {
         pub c_iflag: ::tcflag_t,
         pub c_oflag: ::tcflag_t,
@@ -105,6 +111,7 @@ s! {
         pub c_cc: [::cc_t; ::NCCS]
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct flock64 {
         pub l_type: ::c_short,
         pub l_whence: ::c_short,
@@ -125,6 +132,7 @@ s! {
         pub msg_flags: ::c_int,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct statvfs64 {
         pub f_bsize: ::blksize64_t,
         pub f_frsize: ::blksize64_t,
@@ -171,6 +179,7 @@ s! {
         pub int_n_sign_posn: ::c_char,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct tm {
         pub tm_sec: ::c_int,
         pub tm_min: ::c_int,
@@ -195,22 +204,26 @@ s! {
         pub ai_eflags: ::c_int,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct in_addr {
         pub s_addr: in_addr_t
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct ip_mreq_source {
         pub imr_multiaddr: in_addr,
         pub imr_sourceaddr: in_addr,
         pub imr_interface: in_addr,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sockaddr {
         pub sa_len: ::c_uchar,
         pub sa_family: sa_family_t,
         pub sa_data: [::c_char; 14],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sockaddr_dl {
         pub sdl_len: ::c_uchar,
         pub sdl_family: ::c_uchar,
@@ -222,6 +235,7 @@ s! {
         pub sdl_data: [::c_char; 120],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sockaddr_in {
         pub sin_len: ::c_uchar,
         pub sin_family: sa_family_t,
@@ -230,6 +244,7 @@ s! {
         pub sin_zero: [::c_char; 8]
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sockaddr_in6 {
         pub sin6_len: ::c_uchar,
         pub sin6_family: ::c_uchar,
@@ -239,6 +254,7 @@ s! {
         pub sin6_scope_id: ::uint32_t
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sockaddr_storage {
         pub __ss_len: ::c_uchar,
         pub ss_family: sa_family_t,
@@ -247,17 +263,20 @@ s! {
         __ss_pad2: [::c_char; 1265],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sockaddr_un {
         pub sun_len: ::c_uchar,
         pub sun_family: sa_family_t,
         pub sun_path: [::c_char; 1023]
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct st_timespec {
         pub tv_sec: ::time_t,
         pub tv_nsec: ::c_int,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct statfs64 {
         pub f_version: ::c_int,
         pub f_type: ::c_int,
@@ -289,6 +308,7 @@ s! {
         pub pw_shell: *mut ::c_char
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct utsname {
         pub sysname: [::c_char; 32],
         pub nodename: [::c_char; 32],
@@ -297,12 +317,14 @@ s! {
         pub machine: [::c_char; 32],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct xutsname {
         pub nid: ::c_uint,
         pub reserved: ::c_int,
         pub longnid: ::c_ulonglong,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct cmsghdr {
         pub cmsg_len: ::socklen_t,
         pub cmsg_level: ::c_int,
@@ -318,10 +340,12 @@ s! {
     }
 
     // Should be union with another 'sival_int'
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sigval64 {
         pub sival_ptr: ::c_ulonglong,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sigevent64 {
         pub sigev_value: sigval64,
         pub sigev_signo: ::c_int,
@@ -335,6 +359,7 @@ s! {
         pub sevt_signo: signal_t,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct poll_ctl {
         pub cmd: ::c_short,
         pub events: ::c_short,
@@ -353,11 +378,13 @@ s! {
         pub bytes_sent: ::uint64_t,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct mmsghdr {
         pub msg_hdr: ::msghdr,
         pub msg_len: ::c_uint,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sched_param {
         pub sched_priority: ::c_int,
         pub sched_policy: ::c_int,
@@ -371,6 +398,7 @@ s! {
         pub __pad: [::c_int; 4],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct posix_spawnattr_t {
         pub posix_attr_flags: ::c_short,
         pub posix_attr_pgroup: ::pid_t,
@@ -388,6 +416,7 @@ s! {
         pub gl_ptx: *mut ::c_void,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct mallinfo {
         pub arena: ::c_ulong,
         pub ordblks: ::c_int,
@@ -401,11 +430,13 @@ s! {
         pub keepcost: ::c_int,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct utmp_exit_status {
         pub e_termination: ::c_short,
         pub e_exit: ::c_short,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct utmp {
         pub ut_user: [::c_char; 256],
         pub ut_id: [::c_char; 14],
@@ -420,6 +451,7 @@ s! {
         pub __reservedV: [::c_int; 6],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct regmatch_t {
         pub rm_so: regoff_t,
         pub rm_eo: regoff_t,
@@ -439,11 +471,13 @@ s! {
         pub __unused: [*mut ::c_void; 34],
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct rlimit64 {
         pub rlim_cur: rlim64_t,
         pub rlim_max: rlim64_t,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct shmid_ds {
         pub shm_perm: ipc_perm,
         pub shm_segsz: ::size_t,
@@ -462,6 +496,7 @@ s! {
         pub shm_reserved1: ::int64_t,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct stat64 {
         pub st_dev: dev_t,
         pub st_ino: ino_t,
@@ -494,6 +529,7 @@ s! {
         pub mnt_passno: ::c_int,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct ipc_perm {
         pub uid: ::uid_t,
         pub gid: ::gid_t,
@@ -510,13 +546,15 @@ s! {
         pub data: *mut ::c_void,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct mq_attr {
         pub mq_flags: ::c_long,
         pub mq_maxmsg: ::c_long,
         pub mq_msgsize: ::c_long,
         pub mq_curmsgs: ::c_long,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct sembuf {
         pub sem_num: ::c_ushort,
         pub sem_op: ::c_short,
@@ -528,6 +566,7 @@ s! {
         pub if_name: *mut ::c_char,
     }
 
+    #[cfg_attr(feature = "zerocopy", derive(FromZeroes, FromBytes, AsBytes))]
     pub struct itimerspec {
         pub it_interval: ::timespec,
         pub it_value: ::timespec,