--- /dev/null
+//! Wrapper functions for the libc xattr calls
+
+extern crate libc;
+
+use std::os::unix::io::RawFd;
+use nix::errno::Errno;
+use crate::pxar::{CaFormatXAttr, CaFormatFCaps};
+
+pub fn flistxattr(fd: RawFd) -> Result<Vec<u8>, nix::errno::Errno> {
+ // Initial buffer size for the attribute list, if content does not fit
+ // it gets dynamically increased until big enough.
+ let mut size = 256;
+ let mut buffer = vec![0u8; size];
+ let mut bytes = unsafe {
+ libc::flistxattr(fd, buffer.as_mut_ptr() as *mut i8, buffer.len())
+ };
+ while bytes < 0 {
+ let err = Errno::last();
+ match err {
+ Errno::ERANGE => {
+ // Buffer was not big enough to fit the list, retry with double the size
+ if size * 2 < size { return Err(Errno::ENOMEM); }
+ size *= 2;
+ },
+ _ => return Err(err),
+ }
+ // Retry to read the list with new buffer
+ buffer.resize(size, 0);
+ bytes = unsafe {
+ libc::flistxattr(fd, buffer.as_mut_ptr() as *mut i8, buffer.len())
+ };
+ }
+ buffer.resize(bytes as usize, 0);
+
+ Ok(buffer)
+}
+
+pub fn fgetxattr(fd: RawFd, name: &[u8]) -> Result<Vec<u8>, nix::errno::Errno> {
+ let mut size = 256;
+ let mut buffer = vec![0u8; size];
+ let mut bytes = unsafe {
+ libc::fgetxattr(fd, name.as_ptr() as *const i8, buffer.as_mut_ptr() as *mut core::ffi::c_void, buffer.len())
+ };
+ while bytes < 0 {
+ let err = Errno::last();
+ match err {
+ Errno::ERANGE => {
+ // Buffer was not big enough to fit the value, retry with double the size
+ if size * 2 < size { return Err(Errno::ENOMEM); }
+ size *= 2;
+ },
+ _ => return Err(err),
+ }
+ buffer.resize(size, 0);
+ bytes = unsafe {
+ libc::fgetxattr(fd, name.as_ptr() as *const i8, buffer.as_mut_ptr() as *mut core::ffi::c_void, buffer.len())
+ };
+ }
+ buffer.resize(bytes as usize, 0);
+
+ Ok(buffer)
+}
+
+pub fn fsetxattr(fd: RawFd, xattr: CaFormatXAttr) -> Result<(), nix::errno::Errno> {
+ let mut name = xattr.name.clone();
+ name.push('\0' as u8);
+ let flags = 0 as libc::c_int;
+ let result = unsafe {
+ libc::fsetxattr(fd, name.as_ptr() as *const libc::c_char, xattr.value.as_ptr() as *const libc::c_void, xattr.value.len(), flags)
+ };
+ if result < 0 {
+ let err = Errno::last();
+ return Err(err);
+ }
+
+ Ok(())
+}
+
+pub fn fsetxattr_fcaps(fd: RawFd, fcaps: CaFormatFCaps) -> Result<(), nix::errno::Errno> {
+ // TODO casync checks and removes capabilities if they are set
+ let name = b"security.capability\0";
+ let flags = 0 as libc::c_int;
+ let result = unsafe {
+ libc::fsetxattr(fd, name.as_ptr() as *const libc::c_char, fcaps.data.as_ptr() as *const libc::c_void, fcaps.data.len(), flags)
+ };
+ if result < 0 {
+ let err = Errno::last();
+ return Err(err);
+ }
+
+ Ok(())
+}
+