libstd: win: Replace GetUserProfileDirectoryW by SHGetFolderPathW

The later is allowed on UWP

Author: chouquette

src/libstd/sys/windows/c.rs

@@ -108,6 +108,15 @@ pub const SECURITY_SQOS_PRESENT: DWORD = 0x00100000;
 
 pub const FIONBIO: c_ulong = 0x8004667e;
 
+pub const CSIDL_PROFILE: c_int = 0x0028;
+
+#[repr(C)]
+#[allow(dead_code)] // we only use some variants
+pub enum SHGFP_TYPE {
+    SHGFP_TYPE_CURRENT = 0,
+    SHGFP_TYPE_DEFAULT = 1
+}
+
 #[cfg(target_arch = "arm")]
 const ARM_MAX_BREAKPOINTS: usize = 8;
 #[cfg(target_arch = "arm")]
@@ -154,7 +163,6 @@ pub const WSAECONNREFUSED: c_int = 10061;
 
 pub const MAX_PROTOCOL_CHAIN: DWORD = 7;
 
-pub const TOKEN_READ: DWORD = 0x20008;
 pub const MAXIMUM_REPARSE_DATA_BUFFER_SIZE: usize = 16 * 1024;
 pub const FSCTL_GET_REPARSE_POINT: DWORD = 0x900a8;
 pub const IO_REPARSE_TAG_SYMLINK: DWORD = 0xa000000c;
@@ -1056,9 +1064,6 @@ extern "system" {
     pub fn GetCommandLineW() -> *mut LPCWSTR;
     pub fn GetTempPathW(nBufferLength: DWORD,
                         lpBuffer: LPCWSTR) -> DWORD;
-    pub fn OpenProcessToken(ProcessHandle: HANDLE,
-                            DesiredAccess: DWORD,
-                            TokenHandle: *mut HANDLE) -> BOOL;
     pub fn GetCurrentProcess() -> HANDLE;
     pub fn GetCurrentThread() -> HANDLE;
     pub fn GetStdHandle(which: DWORD) -> HANDLE;
@@ -1083,9 +1088,9 @@ extern "system" {
     pub fn SwitchToThread() -> BOOL;
     pub fn Sleep(dwMilliseconds: DWORD);
     pub fn GetProcessId(handle: HANDLE) -> DWORD;
-    pub fn GetUserProfileDirectoryW(hToken: HANDLE,
-                                    lpProfileDir: LPWSTR,
-                                    lpcchSize: *mut DWORD) -> BOOL;
+    pub fn SHGetFolderPathW(handle: HANDLE, csidl: c_int,
+                            hToken: HANDLE, dwFlags: DWORD,
+                            pszPath: LPWSTR) -> DWORD;
     #[cfg(not(target_os = "uwp"))]
     pub fn SetHandleInformation(hObject: HANDLE,
                                 dwMask: DWORD,

src/libstd/sys/windows/os.rs

@@ -13,7 +13,6 @@ use crate::path::{self, PathBuf};
 use crate::ptr;
 use crate::slice;
 use crate::sys::{c, cvt};
-use crate::sys::handle::Handle;
 
 use super::to_u16s;
 
@@ -288,19 +287,14 @@ pub fn home_dir() -> Option<PathBuf> {
     crate::env::var_os("HOME").or_else(|| {
         crate::env::var_os("USERPROFILE")
     }).map(PathBuf::from).or_else(|| unsafe {
-        let me = c::GetCurrentProcess();
-        let mut token = ptr::null_mut();
-        if c::OpenProcessToken(me, c::TOKEN_READ, &mut token) == 0 {
-            return None
+        let mut bufArray = [0u16; 260]; // MAX_PATH
+        let buf = bufArray[..].as_mut_ptr();
+        match c::SHGetFolderPathW(ptr::null_mut(), c::CSIDL_PROFILE,
+                                  ptr::null_mut(), c::SHGFP_TYPE::SHGFP_TYPE_CURRENT as u32,
+                                  buf) {
+            0 => Some(super::os2path(&bufArray[..])),
+            _ => None
         }
-        let _handle = Handle::new(token);
-        super::fill_utf16_buf(|buf, mut sz| {
-            match c::GetUserProfileDirectoryW(token, buf, &mut sz) {
-                0 if c::GetLastError() != c::ERROR_INSUFFICIENT_BUFFER => 0,
-                0 => sz,
-                _ => sz - 1, // sz includes the null terminator
-            }
-        }, super::os2path).ok()
     })
 }