Add FD_* macros (#45)

Author: notgull

src/lib.rs

@@ -131,6 +131,41 @@ pub mod cmsg_macros {
     }
 }
 
+#[cfg(feature = "general")]
+pub mod select_macros {
+    use crate::ctypes::c_int;
+    use crate::general::__kernel_fd_set;
+    use core::mem::size_of;
+
+    pub unsafe fn FD_CLR(fd: c_int, set: *mut __kernel_fd_set) {
+        let bytes = set as *mut u8;
+        if fd >= 0 {
+            *bytes.offset((fd / 8) as isize) &= !(1 << (fd % 8));
+        }
+    }
+
+    pub unsafe fn FD_SET(fd: c_int, set: *mut __kernel_fd_set) {
+        let bytes = set as *mut u8;
+        if fd >= 0 {
+            *bytes.offset((fd / 8) as isize) |= 1 << (fd % 8);
+        }
+    }
+
+    pub unsafe fn FD_ISSET(fd: c_int, set: *const __kernel_fd_set) -> bool {
+        let bytes = set as *const u8;
+        if fd >= 0 {
+            *bytes.offset((fd / 8) as isize) & (1 << (fd % 8)) != 0
+        } else {
+            false
+        }
+    }
+
+    pub unsafe fn FD_ZERO(set: *mut __kernel_fd_set) {
+        let bytes = set as *mut u8;
+        core::ptr::write_bytes(bytes, 0, size_of::<__kernel_fd_set>());
+    }
+}
+
 // The rest of this file is auto-generated!
 #[cfg(feature = "errno")]
 #[cfg(target_arch = "arm")]