| use super::*; |
| use imp::*; |
| |
| /// A BSTR string ([BSTR](https://learn.microsoft.com/en-us/previous-versions/windows/desktop/automat/string-manipulation-functions)) |
| /// is a length-prefixed wide string. |
| #[repr(transparent)] |
| pub struct BSTR(*const u16); |
| |
| impl BSTR { |
| /// Create an empty `BSTR`. |
| /// |
| /// This function does not allocate memory. |
| pub const fn new() -> Self { |
| Self(std::ptr::null_mut()) |
| } |
| |
| /// Returns `true` if the string is empty. |
| pub fn is_empty(&self) -> bool { |
| self.len() == 0 |
| } |
| |
| /// Returns the length of the string. |
| pub fn len(&self) -> usize { |
| if self.0.is_null() { |
| 0 |
| } else { |
| unsafe { SysStringLen(self.0) as usize } |
| } |
| } |
| |
| /// Get the string as 16-bit wide characters (wchars). |
| pub fn as_wide(&self) -> &[u16] { |
| if self.0.is_null() { |
| return &[]; |
| } |
| |
| unsafe { std::slice::from_raw_parts(self.0, self.len()) } |
| } |
| |
| /// Create a `BSTR` from a slice of 16 bit characters (wchars). |
| pub fn from_wide(value: &[u16]) -> Result<Self> { |
| if value.is_empty() { |
| return Ok(Self::new()); |
| } |
| |
| let result = unsafe { Self(SysAllocStringLen(value.as_ptr(), value.len() as _)) }; |
| |
| if result.is_empty() { |
| Err(E_OUTOFMEMORY.into()) |
| } else { |
| Ok(result) |
| } |
| } |
| |
| #[doc(hidden)] |
| pub unsafe fn from_raw(raw: *const u16) -> Self { |
| Self(raw) |
| } |
| |
| #[doc(hidden)] |
| pub fn into_raw(self) -> *const u16 { |
| unsafe { std::mem::transmute(self) } |
| } |
| } |
| |
| impl std::clone::Clone for BSTR { |
| fn clone(&self) -> Self { |
| Self::from_wide(self.as_wide()).unwrap() |
| } |
| } |
| |
| impl std::convert::From<&str> for BSTR { |
| fn from(value: &str) -> Self { |
| let value: std::vec::Vec<u16> = value.encode_utf16().collect(); |
| Self::from_wide(&value).unwrap() |
| } |
| } |
| |
| impl std::convert::From<std::string::String> for BSTR { |
| fn from(value: std::string::String) -> Self { |
| value.as_str().into() |
| } |
| } |
| |
| impl std::convert::From<&std::string::String> for BSTR { |
| fn from(value: &std::string::String) -> Self { |
| value.as_str().into() |
| } |
| } |
| |
| impl<'a> std::convert::TryFrom<&'a BSTR> for std::string::String { |
| type Error = std::string::FromUtf16Error; |
| |
| fn try_from(value: &BSTR) -> std::result::Result<Self, Self::Error> { |
| std::string::String::from_utf16(value.as_wide()) |
| } |
| } |
| |
| impl std::convert::TryFrom<BSTR> for std::string::String { |
| type Error = std::string::FromUtf16Error; |
| |
| fn try_from(value: BSTR) -> std::result::Result<Self, Self::Error> { |
| std::string::String::try_from(&value) |
| } |
| } |
| |
| impl std::default::Default for BSTR { |
| fn default() -> Self { |
| Self(std::ptr::null_mut()) |
| } |
| } |
| |
| impl std::fmt::Display for BSTR { |
| fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { |
| std::write!(f, "{}", windows::core::Decode(|| std::char::decode_utf16(self.as_wide().iter().cloned()))) |
| } |
| } |
| |
| impl std::fmt::Debug for BSTR { |
| fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { |
| std::write!(f, "{}", self) |
| } |
| } |
| |
| impl std::cmp::PartialEq for BSTR { |
| fn eq(&self, other: &Self) -> bool { |
| self.as_wide() == other.as_wide() |
| } |
| } |
| |
| impl std::cmp::Eq for BSTR {} |
| |
| impl std::cmp::PartialEq<BSTR> for &str { |
| fn eq(&self, other: &BSTR) -> bool { |
| other == self |
| } |
| } |
| |
| impl std::cmp::PartialEq<BSTR> for String { |
| fn eq(&self, other: &BSTR) -> bool { |
| other == self |
| } |
| } |
| |
| impl<T: AsRef<str> + ?Sized> std::cmp::PartialEq<T> for BSTR { |
| fn eq(&self, other: &T) -> bool { |
| self.as_wide().iter().copied().eq(other.as_ref().encode_utf16()) |
| } |
| } |
| |
| impl std::ops::Drop for BSTR { |
| fn drop(&mut self) { |
| if !self.0.is_null() { |
| unsafe { SysFreeString(self.0) } |
| } |
| } |
| } |
| |
| impl TypeKind for BSTR { |
| type TypeKind = ValueType; |
| } |