use crate::ic::{stable_bytes, stable_grow, stable_read, stable_size, stable_write, StableSize};
use candid::utils::{ArgumentDecoder, ArgumentEncoder};
use std::io;
pub use ic_kit_sys::types::StableMemoryError;
pub struct StableWriter {
offset: StableSize,
capacity: StableSize,
}
impl Default for StableWriter {
fn default() -> Self {
let capacity = stable_size();
Self {
offset: 0,
capacity,
}
}
}
impl StableWriter {
pub fn new(offset: StableSize) -> Self {
StableWriter {
offset,
capacity: stable_size(),
}
}
pub fn offset(&self) -> StableSize {
self.offset
}
pub fn grow(&mut self, added_pages: StableSize) -> Result<(), StableMemoryError> {
let old_page_count = stable_grow(added_pages)?;
self.capacity = old_page_count + added_pages;
Ok(())
}
pub fn write(&mut self, buf: &[u8]) -> Result<usize, StableMemoryError> {
if self.offset + (buf.len() as StableSize) > (self.capacity << 16) {
self.grow((buf.len() >> 16) as StableSize + 1)?;
}
stable_write(self.offset, buf);
self.offset += buf.len() as StableSize;
Ok(buf.len())
}
}
impl io::Write for StableWriter {
fn write(&mut self, buf: &[u8]) -> Result<usize, io::Error> {
self.write(buf)
.map_err(|_| io::Error::new(io::ErrorKind::Other, "Out Of Memory"))
}
fn flush(&mut self) -> Result<(), io::Error> {
Ok(())
}
}
pub struct StableReader {
offset: StableSize,
}
impl Default for StableReader {
fn default() -> Self {
Self { offset: 0 }
}
}
impl StableReader {
pub fn new(offset: StableSize) -> Self {
StableReader { offset }
}
pub fn read(&mut self, buf: &mut [u8]) -> Result<usize, StableMemoryError> {
stable_read(self.offset, buf);
self.offset += buf.len() as StableSize;
Ok(buf.len())
}
}
impl io::Read for StableReader {
fn read(&mut self, buf: &mut [u8]) -> Result<usize, io::Error> {
self.read(buf)
.map_err(|_| io::Error::new(io::ErrorKind::Other, "Unexpected error."))
}
}
#[deprecated(
since = "0.5.0",
note = "This is a non-performant legacy from IC-CDK for us to deal with."
)]
pub fn stable_store<T>(data: T) -> Result<(), candid::Error>
where
T: ArgumentEncoder,
{
candid::write_args(&mut StableWriter::default(), data)
}
#[deprecated(
since = "0.5.0",
note = "This is a non-performant legacy from IC-CDK for us to deal with."
)]
pub fn stable_restore<T>() -> Result<T, String>
where
T: for<'de> ArgumentDecoder<'de>,
{
let bytes = stable_bytes();
let mut de =
candid::de::IDLDeserialize::new(bytes.as_slice()).map_err(|e| format!("{:?}", e))?;
let res = ArgumentDecoder::decode(&mut de).map_err(|e| format!("{:?}", e))?;
Ok(res)
}