Use CopyFileEx for fs::copy on Windows

Signed-off-by: Peter Atashian <retep998@gmail.com>

src/libstd/fs.rs

@@ -21,7 +21,7 @@ use core::prelude::*;
 
 use fmt;
 use ffi::OsString;
-use io::{self, Error, ErrorKind, SeekFrom, Seek, Read, Write};
+use io::{self, SeekFrom, Seek, Read, Write};
 use path::{Path, PathBuf};
 use sys::fs as fs_imp;
 use sys_common::{AsInnerMut, FromInner, AsInner};
@@ -858,20 +858,7 @@ pub fn rename<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()>
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub fn copy<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<u64> {
-    let from = from.as_ref();
-    let to = to.as_ref();
-    if !from.is_file() {
-        return Err(Error::new(ErrorKind::InvalidInput,
-                              "the source path is not an existing file"))
-    }
-
-    let mut reader = try!(File::open(from));
-    let mut writer = try!(File::create(to));
-    let perm = try!(reader.metadata()).permissions();
-
-    let ret = try!(io::copy(&mut reader, &mut writer));
-    try!(set_permissions(to, perm));
-    Ok(ret)
+    fs_imp::copy(from.as_ref(), to.as_ref())
 }
 
 /// Creates a new hard link on the filesystem.

src/libstd/sys/unix/fs.rs

@@ -516,3 +516,20 @@ pub fn canonicalize(p: &Path) -> io::Result<PathBuf> {
     buf.truncate(p);
     Ok(PathBuf::from(OsString::from_vec(buf)))
 }
+
+pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
+    let from = from.as_ref();
+    let to = to.as_ref();
+    if !from.is_file() {
+        return Err(Error::new(ErrorKind::InvalidInput,
+                              "the source path is not an existing file"))
+    }
+
+    let mut reader = try!(File::open(from));
+    let mut writer = try!(File::create(to));
+    let perm = try!(reader.metadata()).permissions();
+
+    let ret = try!(io::copy(&mut reader, &mut writer));
+    try!(set_permissions(to, perm));
+    Ok(ret)
+}

src/libstd/sys/windows/c.rs

@@ -66,6 +66,13 @@ pub const STD_ERROR_HANDLE: libc::DWORD = -12i32 as libc::DWORD;
 
 pub const HANDLE_FLAG_INHERIT: libc::DWORD = 0x00000001;
 
+pub const PROGRESS_CONTINUE: libc::DWORD = 0;
+pub const PROGRESS_CANCEL: libc::DWORD = 1;
+pub const PROGRESS_STOP: libc::DWORD = 2;
+pub const PROGRESS_QUIET: libc::DWORD = 3;
+
+pub const COPY_FILE_ALLOW_DECRYPTED_DESTINATION: libc::DWORD = 0x00000008;
+
 #[repr(C)]
 #[cfg(target_arch = "x86")]
 pub struct WSADATA {
@@ -249,6 +256,19 @@ pub type PCONDITION_VARIABLE = *mut CONDITION_VARIABLE;
 pub type PSRWLOCK = *mut SRWLOCK;
 pub type ULONG = c_ulong;
 pub type ULONG_PTR = c_ulong;
+pub type LPBOOL = *mut BOOL;
+
+pub type LPPROGRESS_ROUTINE = ::option::Option<unsafe extern "system" fn(
+    TotalFileSize: libc::LARGE_INTEGER,
+    TotalBytesTransferred: libc::LARGE_INTEGER,
+    StreamSize: libc::LARGE_INTEGER,
+    StreamBytesTransferred: libc::LARGE_INTEGER,
+    dwStreamNumber: DWORD,
+    dwCallbackReason: DWORD,
+    hSourceFile: HANDLE,
+    hDestinationFile: HANDLE,
+    lpData: LPVOID,
+) -> DWORD>;
 
 #[repr(C)]
 pub struct CONDITION_VARIABLE { pub ptr: LPVOID }
@@ -413,6 +433,14 @@ extern "system" {
     pub fn SetHandleInformation(hObject: libc::HANDLE,
                                 dwMask: libc::DWORD,
                                 dwFlags: libc::DWORD) -> libc::BOOL;
+    pub fn CopyFileExW(
+        lpExistingFileName: libc::LPCWSTR,
+        lpNewFileName: libc::LPCWSTR,
+        lpProgressRoutine: LPPROGRESS_ROUTINE,
+        lpData: libc::LPVOID,
+        pbCancel: LPBOOL,
+        dwCopyFlags: libc::DWORD,
+    ) -> libc::BOOL;
 }
 
 // Functions that aren't available on Windows XP, but we still use them and just

src/libstd/sys/windows/fs.rs

@@ -575,3 +575,31 @@ pub fn canonicalize(p: &Path) -> io::Result<PathBuf> {
         PathBuf::from(OsString::from_wide(buf))
     })
 }
+
+pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
+    unsafe extern "system" fn callback(
+        _TotalFileSize: libc::LARGE_INTEGER,
+        TotalBytesTransferred: libc::LARGE_INTEGER,
+        _StreamSize: libc::LARGE_INTEGER,
+        _StreamBytesTransferred: libc::LARGE_INTEGER,
+        _dwStreamNumber: libc::DWORD,
+        _dwCallbackReason: libc::DWORD,
+        _hSourceFile: HANDLE,
+        _hDestinationFile: HANDLE,
+        lpData: libc::LPVOID,
+    ) -> libc::DWORD {
+        // Alternative is to just grab TotalFileSize and return PROGRESS_QUIET
+        *(lpData as *mut i64) = TotalBytesTransferred;
+        c::PROGRESS_CONTINUE
+    }
+    let pfrom = to_utf16(from);
+    let pto = to_utf16(to);
+    let mut size = 0i64;
+    // Do we want to allow encrypted files to be copied to a decrypted destination?
+    try!(cvt(unsafe {
+        c::CopyFileExW(pfrom.as_ptr(), pto.as_ptr(), Some(callback),
+                       &mut size as *mut _ as *mut _, ptr::null_mut(),
+                       c::COPY_FILE_ALLOW_DECRYPTED_DESTINATION)
+    }));
+    Ok(size as u64)
+}