Merge pull request #4208 from igankevich/const-fn-major-minor

Make `makedev`, `major`, `minor` const
rust-lang · Feb 24, 2025 · 989b64a · 989b64a
2 parents 3695157 + 37c3333
commit 989b64a
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Showing 18 changed files with 210 additions and 159 deletions.
diff --git a/libc-test/src/makedev.c b/libc-test/src/makedev.c
@@ -3,11 +3,19 @@
 #include <sys/sysmacros.h>
 #endif
 
-// Since makedev is a macro instead of a function, it isn't available to FFI.
-// libc must reimplement it, which is error-prone.  This file provides FFI
-// access to the actual macro so it can be tested against the Rust
-// reimplementation.
+// Since makedev, major, minor are macros instead of functions, they aren't
+// available to FFI. libc must reimplement them, which is error-prone. This
+// file provides FFI access to the actual macros so they can be tested against
+// the Rust reimplementation.
 
 dev_t makedev_ffi(unsigned major, unsigned minor) {
 	return makedev(major, minor);
 }
+
+unsigned int major_ffi(dev_t dev) {
+    return major(dev);
+}
+
+unsigned int minor_ffi(dev_t dev) {
+    return minor(dev);
+}
diff --git a/libc-test/test/makedev.rs b/libc-test/test/makedev.rs
@@ -1,6 +1,50 @@
-//! Compare libc's makdev function against the actual C macros, for various
+//! Compare libc's makedev, major, minor functions against the actual C macros, for various
 //! inputs.
 
+#[cfg(any(target_os = "solaris", target_os = "illumos"))]
+mod ret {
+    pub type MajorRetType = libc::major_t;
+    pub type MinorRetType = libc::minor_t;
+}
+
+#[cfg(any(
+    target_os = "linux",
+    target_os = "l4re",
+    target_os = "emscripten",
+    target_os = "fuchsia",
+    target_os = "aix",
+    target_os = "nto",
+    target_os = "hurd",
+    target_os = "openbsd",
+))]
+mod ret {
+    pub type MajorRetType = libc::c_uint;
+    pub type MinorRetType = libc::c_uint;
+}
+
+#[cfg(any(
+    target_os = "android",
+    target_os = "dragonfly",
+    target_os = "netbsd",
+    target_os = "freebsd",
+))]
+mod ret {
+    pub type MajorRetType = libc::c_int;
+    pub type MinorRetType = libc::c_int;
+}
+
+#[cfg(any(
+    target_os = "macos",
+    target_os = "ios",
+    target_os = "tvos",
+    target_os = "watchos",
+    target_os = "visionos"
+))]
+mod ret {
+    pub type MajorRetType = i32;
+    pub type MinorRetType = i32;
+}
+
 #[cfg(any(
     target_os = "android",
     target_os = "dragonfly",
@@ -14,13 +58,21 @@
 mod t {
     use libc::{self, c_uint, dev_t};
 
+    use super::ret::*;
+
     extern "C" {
         pub fn makedev_ffi(major: c_uint, minor: c_uint) -> dev_t;
+        pub fn major_ffi(dev: dev_t) -> c_uint;
+        pub fn minor_ffi(dev: dev_t) -> c_uint;
     }
 
     fn compare(major: c_uint, minor: c_uint) {
-        let expected = unsafe { makedev_ffi(major, minor) };
-        assert_eq!(libc::makedev(major, minor), expected);
+        let dev = unsafe { makedev_ffi(major, minor) };
+        assert_eq!(libc::makedev(major, minor), dev);
+        let major = unsafe { major_ffi(dev) };
+        assert_eq!(libc::major(dev), major as MajorRetType);
+        let minor = unsafe { minor_ffi(dev) };
+        assert_eq!(libc::minor(dev), minor as MinorRetType);
     }
 
     // Every OS should be able to handle 8 bit major and minor numbers

diff --git a/src/fuchsia/mod.rs b/src/fuchsia/mod.rs
@@ -3423,20 +3423,6 @@ f! {
         set1.bits == set2.bits
     }
 
-    pub fn major(dev: crate::dev_t) -> c_uint {
-        let mut major = 0;
-        major |= (dev & 0x00000000000fff00) >> 8;
-        major |= (dev & 0xfffff00000000000) >> 32;
-        major as c_uint
-    }
-
-    pub fn minor(dev: crate::dev_t) -> c_uint {
-        let mut minor = 0;
-        minor |= (dev & 0x00000000000000ff) >> 0;
-        minor |= (dev & 0x00000ffffff00000) >> 12;
-        minor as c_uint
-    }
-
     pub fn CMSG_DATA(cmsg: *const cmsghdr) -> *mut c_uchar {
         cmsg.offset(1) as *mut c_uchar
     }
@@ -3519,6 +3505,20 @@ safe_f! {
         dev |= (minor & 0xffffff00) << 12;
         dev
     }
+
+    pub {const} fn major(dev: crate::dev_t) -> c_uint {
+        let mut major = 0;
+        major |= (dev & 0x00000000000fff00) >> 8;
+        major |= (dev & 0xfffff00000000000) >> 32;
+        major as c_uint
+    }
+
+    pub {const} fn minor(dev: crate::dev_t) -> c_uint {
+        let mut minor = 0;
+        minor |= (dev & 0x00000000000000ff) >> 0;
+        minor |= (dev & 0x00000ffffff00000) >> 12;
+        minor as c_uint
+    }
 }
 
 fn __CMSG_LEN(cmsg: *const cmsghdr) -> ssize_t {

diff --git a/src/unix/aix/mod.rs b/src/unix/aix/mod.rs
@@ -2545,25 +2545,6 @@ f! {
         let fd = fd as usize;
         return ((*set).fds_bits[fd / bits] & (1 << (fd % bits))) != 0;
     }
-
-    pub fn major(dev: crate::dev_t) -> c_uint {
-        let x = dev >> 16;
-        x as c_uint
-    }
-
-    pub fn minor(dev: crate::dev_t) -> c_uint {
-        let y = dev & 0xFFFF;
-        y as c_uint
-    }
-
-    pub fn makedev(major: c_uint, minor: c_uint) -> crate::dev_t {
-        let major = major as crate::dev_t;
-        let minor = minor as crate::dev_t;
-        let mut dev = 0;
-        dev |= major << 16;
-        dev |= minor;
-        dev
-    }
 }
 
 safe_f! {
@@ -2611,6 +2592,25 @@ safe_f! {
     pub {const} fn WCOREDUMP(_status: c_int) -> bool {
         false
     }
+
+    pub {const} fn major(dev: crate::dev_t) -> c_uint {
+        let x = dev >> 16;
+        x as c_uint
+    }
+
+    pub {const} fn minor(dev: crate::dev_t) -> c_uint {
+        let y = dev & 0xFFFF;
+        y as c_uint
+    }
+
+    pub {const} fn makedev(major: c_uint, minor: c_uint) -> crate::dev_t {
+        let major = major as crate::dev_t;
+        let minor = minor as crate::dev_t;
+        let mut dev = 0;
+        dev |= major << 16;
+        dev |= minor;
+        dev
+    }
 }
 
 #[link(name = "thread")]

diff --git a/src/unix/bsd/apple/mod.rs b/src/unix/bsd/apple/mod.rs
@@ -5543,18 +5543,6 @@ f! {
     pub {const} fn VM_MAKE_TAG(id: u8) -> u32 {
         (id as u32) << 24u32
     }
-
-    pub fn major(dev: dev_t) -> i32 {
-        (dev >> 24) & 0xff
-    }
-
-    pub fn minor(dev: dev_t) -> i32 {
-        dev & 0xffffff
-    }
-
-    pub fn makedev(major: i32, minor: i32) -> dev_t {
-        (major << 24) | minor
-    }
 }
 
 safe_f! {
@@ -5577,6 +5565,18 @@ safe_f! {
     pub {const} fn WIFSTOPPED(status: c_int) -> bool {
         _WSTATUS(status) == _WSTOPPED && WSTOPSIG(status) != 0x13
     }
+
+    pub {const} fn makedev(major: i32, minor: i32) -> dev_t {
+        (major << 24) | minor
+    }
+
+    pub {const} fn major(dev: dev_t) -> i32 {
+        (dev >> 24) & 0xff
+    }
+
+    pub {const} fn minor(dev: dev_t) -> i32 {
+        dev & 0xffffff
+    }
 }
 
 extern "C" {

diff --git a/src/unix/bsd/freebsdlike/dragonfly/mod.rs b/src/unix/bsd/freebsdlike/dragonfly/mod.rs
@@ -1590,14 +1590,6 @@ f! {
         let (idx, offset) = ((cpu >> 6) & 3, cpu & 63);
         0 != cpuset.ary[idx] & (1 << offset)
     }
-
-    pub fn major(dev: crate::dev_t) -> c_int {
-        ((dev >> 8) & 0xff) as c_int
-    }
-
-    pub fn minor(dev: crate::dev_t) -> c_int {
-        (dev & 0xffff00ff) as c_int
-    }
 }
 
 safe_f! {
@@ -1613,6 +1605,14 @@ safe_f! {
         dev |= minor;
         dev
     }
+
+    pub {const} fn major(dev: crate::dev_t) -> c_int {
+        ((dev >> 8) & 0xff) as c_int
+    }
+
+    pub {const} fn minor(dev: crate::dev_t) -> c_int {
+        (dev & 0xffff00ff) as c_int
+    }
 }
 
 extern "C" {

diff --git a/src/unix/bsd/freebsdlike/freebsd/freebsd11/mod.rs b/src/unix/bsd/freebsdlike/freebsd/freebsd11/mod.rs
@@ -441,14 +441,12 @@ safe_f! {
         let minor = minor as crate::dev_t;
         (major << 8) | minor
     }
-}
 
-f! {
-    pub fn major(dev: crate::dev_t) -> c_int {
+    pub {const} fn major(dev: crate::dev_t) -> c_int {
         ((dev >> 8) & 0xff) as c_int
     }
 
-    pub fn minor(dev: crate::dev_t) -> c_int {
+    pub {const} fn minor(dev: crate::dev_t) -> c_int {
         (dev & 0xffff00ff) as c_int
     }
 }

diff --git a/src/unix/bsd/freebsdlike/freebsd/freebsd12/mod.rs b/src/unix/bsd/freebsdlike/freebsd/freebsd12/mod.rs
@@ -496,14 +496,12 @@ safe_f! {
         dev |= ((minor & 0xffff00ff) as dev_t) << 0;
         dev
     }
-}
 
-f! {
-    pub fn major(dev: crate::dev_t) -> c_int {
+    pub {const} fn major(dev: crate::dev_t) -> c_int {
         (((dev >> 32) & 0xffffff00) | ((dev >> 8) & 0xff)) as c_int
     }
 
-    pub fn minor(dev: crate::dev_t) -> c_int {
+    pub {const} fn minor(dev: crate::dev_t) -> c_int {
         (((dev >> 24) & 0xff00) | (dev & 0xffff00ff)) as c_int
     }
 }

diff --git a/src/unix/bsd/freebsdlike/freebsd/freebsd13/mod.rs b/src/unix/bsd/freebsdlike/freebsd/freebsd13/mod.rs
@@ -518,14 +518,12 @@ safe_f! {
         dev |= ((minor & 0xffff00ff) as dev_t) << 0;
         dev
     }
-}
 
-f! {
-    pub fn major(dev: crate::dev_t) -> c_int {
+    pub {const} fn major(dev: crate::dev_t) -> c_int {
         (((dev >> 32) & 0xffffff00) | ((dev >> 8) & 0xff)) as c_int
     }
 
-    pub fn minor(dev: crate::dev_t) -> c_int {
+    pub {const} fn minor(dev: crate::dev_t) -> c_int {
         (((dev >> 24) & 0xff00) | (dev & 0xffff00ff)) as c_int
     }
 }

diff --git a/src/unix/bsd/freebsdlike/freebsd/freebsd14/mod.rs b/src/unix/bsd/freebsdlike/freebsd/freebsd14/mod.rs
@@ -518,14 +518,12 @@ safe_f! {
         dev |= ((minor & 0xffff00ff) as dev_t) << 0;
         dev
     }
-}
 
-f! {
-    pub fn major(dev: crate::dev_t) -> c_int {
+    pub {const} fn major(dev: crate::dev_t) -> c_int {
         (((dev >> 32) & 0xffffff00) | ((dev >> 8) & 0xff)) as c_int
     }
 
-    pub fn minor(dev: crate::dev_t) -> c_int {
+    pub {const} fn minor(dev: crate::dev_t) -> c_int {
         (((dev >> 24) & 0xff00) | (dev & 0xffff00ff)) as c_int
     }
 }

diff --git a/src/unix/bsd/freebsdlike/freebsd/freebsd15/mod.rs b/src/unix/bsd/freebsdlike/freebsd/freebsd15/mod.rs
@@ -519,14 +519,12 @@ safe_f! {
         dev |= ((minor & 0xffff00ff) as dev_t) << 0;
         dev
     }
-}
 
-f! {
-    pub fn major(dev: crate::dev_t) -> c_int {
+    pub {const} fn major(dev: crate::dev_t) -> c_int {
         (((dev >> 32) & 0xffffff00) | ((dev >> 8) & 0xff)) as c_int
     }
 
-    pub fn minor(dev: crate::dev_t) -> c_int {
+    pub {const} fn minor(dev: crate::dev_t) -> c_int {
         (((dev >> 24) & 0xff00) | (dev & 0xffff00ff)) as c_int
     }
 }

diff --git a/src/unix/bsd/netbsdlike/netbsd/mod.rs b/src/unix/bsd/netbsdlike/netbsd/mod.rs
@@ -2461,17 +2461,6 @@ f! {
     pub fn PROT_MPROTECT_EXTRACT(x: c_int) -> c_int {
         (x >> 3) & 0x7
     }
-
-    pub fn major(dev: crate::dev_t) -> c_int {
-        (((dev as u32) & 0x000fff00) >> 8) as c_int
-    }
-
-    pub fn minor(dev: crate::dev_t) -> c_int {
-        let mut res = 0;
-        res |= ((dev as u32) & 0xfff00000) >> 12;
-        res |= (dev as u32) & 0x000000ff;
-        res as c_int
-    }
 }
 
 safe_f! {
@@ -2500,6 +2489,17 @@ safe_f! {
         dev |= minor & 0xff;
         dev
     }
+
+    pub {const} fn major(dev: crate::dev_t) -> c_int {
+        (((dev as u32) & 0x000fff00) >> 8) as c_int
+    }
+
+    pub {const} fn minor(dev: crate::dev_t) -> c_int {
+        let mut res = 0;
+        res |= ((dev as u32) & 0xfff00000) >> 12;
+        res |= (dev as u32) & 0x000000ff;
+        res as c_int
+    }
 }
 
 extern "C" {