Struct aster_frame::mm::VmWriter
source · pub struct VmWriter<'a> { /* private fields */ }
Expand description
VmWriter is a writer for writing data to a contiguous range of memory.
Implementations§
source§impl<'a> VmWriter<'a>
impl<'a> VmWriter<'a>
sourcepub const unsafe fn from_raw_parts_mut(ptr: *mut u8, len: usize) -> Self
pub const unsafe fn from_raw_parts_mut(ptr: *mut u8, len: usize) -> Self
Constructs a VmWriter from a pointer and a length.
Safety
User must ensure the memory from ptr
to ptr.add(len)
is contiguous.
User must ensure the memory is valid during the entire period of 'a
.
sourcepub const fn cursor(&self) -> *mut u8
pub const fn cursor(&self) -> *mut u8
Returns the cursor pointer, which refers to the address of the next byte to write.
sourcepub const fn limit(self, max_avail: usize) -> Self
pub const fn limit(self, max_avail: usize) -> Self
Limits the length of available space.
This method ensures the postcondition of self.avail() <= max_avail
.
sourcepub fn skip(self, nbytes: usize) -> Self
pub fn skip(self, nbytes: usize) -> Self
Skips the first nbytes
bytes of data.
The length of available space is decreased accordingly.
Panic
If nbytes
is greater than self.avail()
, then the method panics.
sourcepub fn write(&mut self, reader: &mut VmReader<'_>) -> usize
pub fn write(&mut self, reader: &mut VmReader<'_>) -> usize
Writes data from the reader until one of the two conditions is met:
- The writer has no available space.
- The reader has no remaining data.
Returns the number of bytes written.
It pulls the number of bytes data from the reader and fills in the writer with the number of bytes.
Trait Implementations§
Auto Trait Implementations§
impl<'a> RefUnwindSafe for VmWriter<'a>
impl<'a> !Send for VmWriter<'a>
impl<'a> !Sync for VmWriter<'a>
impl<'a> Unpin for VmWriter<'a>
impl<'a> !UnwindSafe for VmWriter<'a>
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