diff --git a/src/offset/local/tz_info/parser.rs b/src/offset/local/tz_info/parser.rs index 47cc0377e..509c4fef9 100644 --- a/src/offset/local/tz_info/parser.rs +++ b/src/offset/local/tz_info/parser.rs @@ -247,6 +247,21 @@ impl<'a> Cursor<'a> { Ok(u32::from_be_bytes(buf)) } + #[cfg(target_env = "ohos")] + pub(crate) fn seek_after(&mut self, offset: usize) -> Result { + if offset < self.read_count { + return Err(io::Error::from(ErrorKind::UnexpectedEof)); + } + match self.remaining.get((offset - self.read_count)..) { + Some(remaining) => { + self.remaining = remaining; + self.read_count = offset; + Ok(offset) + } + _ => Err(io::Error::from(ErrorKind::UnexpectedEof)), + } + } + /// Read exactly `count` bytes, reducing remaining data and incrementing read count pub(crate) fn read_exact(&mut self, count: usize) -> Result<&'a [u8], io::Error> { match (self.remaining.get(..count), self.remaining.get(count..)) { diff --git a/src/offset/local/tz_info/timezone.rs b/src/offset/local/tz_info/timezone.rs index 1b089902e..b0845c811 100644 --- a/src/offset/local/tz_info/timezone.rs +++ b/src/offset/local/tz_info/timezone.rs @@ -8,6 +8,9 @@ use std::{cmp::Ordering, fmt, str}; use super::rule::{AlternateTime, TransitionRule}; use super::{parser, Error, DAYS_PER_WEEK, SECONDS_PER_DAY}; +#[cfg(target_env = "ohos")] +use crate::offset::local::tz_info::parser::Cursor; + /// Time zone #[derive(Debug, Clone, Eq, PartialEq)] pub(crate) struct TimeZone { @@ -50,6 +53,12 @@ impl TimeZone { } } + // ohos merge all file into tzdata since ver35 + #[cfg(target_env = "ohos")] + { + return Self::from_tz_data(&find_ohos_tz_data(tz_string)?); + } + let mut chars = tz_string.chars(); if chars.next() == Some(':') { return Self::from_file(&mut find_tz_file(chars.as_str())?); @@ -629,6 +638,58 @@ fn find_tz_file(path: impl AsRef) -> Result { } } +#[cfg(target_env = "ohos")] +fn from_tzdata_bytes(bytes: &mut Vec, tz_string: &str) -> Result, Error> { + const VERSION_SIZE: usize = 12; + const OFFSET_SIZE: usize = 4; + const INDEX_CHUNK_SIZE: usize = 48; + const ZONENAME_SIZE: usize = 40; + + let mut cursor = Cursor::new(&bytes); + // version head + let _ = cursor.read_exact(VERSION_SIZE)?; + let index_offset_offset = cursor.read_be_u32()?; + let data_offset_offset = cursor.read_be_u32()?; + // final offset + let _ = cursor.read_be_u32()?; + + cursor.seek_after(index_offset_offset as usize)?; + let mut idx = index_offset_offset; + while idx < data_offset_offset { + let index_buf = cursor.read_exact(ZONENAME_SIZE)?; + let offset = cursor.read_be_u32()?; + let length = cursor.read_be_u32()?; + let zone_name = str::from_utf8(index_buf)?.trim_end_matches('\0'); + if zone_name != tz_string { + idx += INDEX_CHUNK_SIZE as u32; + continue; + } + cursor.seek_after((data_offset_offset + offset) as usize)?; + return match cursor.read_exact(length as usize) { + Ok(result) => Ok(result.to_vec()), + Err(_err) => Err(Error::InvalidTzFile("invalid ohos tzdata chunk")) + }; + } + + Err(Error::Io(io::ErrorKind::NotFound.into())) +} + +#[cfg(target_env = "ohos")] +fn from_tzdata_file(file: &mut File, tz_string: &str) -> Result, Error> { + let mut bytes = Vec::new(); + file.read_to_end(&mut bytes)?; + from_tzdata_bytes(&mut bytes, tz_string) +} + +#[cfg(target_env = "ohos")] +fn find_ohos_tz_data(tz_string: &str) -> Result, Error> { + const TZDATA_PATH: &str = "/system/etc/zoneinfo/tzdata"; + match File::open(TZDATA_PATH) { + Ok(mut file) => from_tzdata_file(&mut file, tz_string), + Err(_err) => Err(Error::InvalidTzFile("invalid ohos tz file")), + } +} + // Possible system timezone directories #[cfg(unix)] const ZONE_INFO_DIRECTORIES: [&str; 4] =