88 lines
3.9 KiB
Rust
88 lines
3.9 KiB
Rust
use std::io;
|
|
use std::io::prelude::*;
|
|
use result::{ZipResult, ZipError};
|
|
use podio::{ReadPodExt, WritePodExt, LittleEndian};
|
|
|
|
pub static LOCAL_FILE_HEADER_SIGNATURE : u32 = 0x04034b50;
|
|
pub static CENTRAL_DIRECTORY_HEADER_SIGNATURE : u32 = 0x02014b50;
|
|
static CENTRAL_DIRECTORY_END_SIGNATURE : u32 = 0x06054b50;
|
|
|
|
pub struct CentralDirectoryEnd
|
|
{
|
|
pub disk_number: u16,
|
|
pub disk_with_central_directory: u16,
|
|
pub number_of_files_on_this_disk: u16,
|
|
pub number_of_files: u16,
|
|
pub central_directory_size: u32,
|
|
pub central_directory_offset: u32,
|
|
pub zip_file_comment: Vec<u8>,
|
|
}
|
|
|
|
impl CentralDirectoryEnd
|
|
{
|
|
pub fn parse<T: Read>(reader: &mut T) -> ZipResult<CentralDirectoryEnd>
|
|
{
|
|
let magic = try!(reader.read_u32::<LittleEndian>());
|
|
if magic != CENTRAL_DIRECTORY_END_SIGNATURE
|
|
{
|
|
return Err(ZipError::InvalidArchive("Invalid digital signature header"))
|
|
}
|
|
let disk_number = try!(reader.read_u16::<LittleEndian>());
|
|
let disk_with_central_directory = try!(reader.read_u16::<LittleEndian>());
|
|
let number_of_files_on_this_disk = try!(reader.read_u16::<LittleEndian>());
|
|
let number_of_files = try!(reader.read_u16::<LittleEndian>());
|
|
let central_directory_size = try!(reader.read_u32::<LittleEndian>());
|
|
let central_directory_offset = try!(reader.read_u32::<LittleEndian>());
|
|
let zip_file_comment_length = try!(reader.read_u16::<LittleEndian>()) as usize;
|
|
let zip_file_comment = try!(reader.read_exact(zip_file_comment_length));
|
|
|
|
Ok(CentralDirectoryEnd
|
|
{
|
|
disk_number: disk_number,
|
|
disk_with_central_directory: disk_with_central_directory,
|
|
number_of_files_on_this_disk: number_of_files_on_this_disk,
|
|
number_of_files: number_of_files,
|
|
central_directory_size: central_directory_size,
|
|
central_directory_offset: central_directory_offset,
|
|
zip_file_comment: zip_file_comment,
|
|
})
|
|
}
|
|
|
|
pub fn find_and_parse<T: Read+io::Seek>(reader: &mut T) -> ZipResult<CentralDirectoryEnd>
|
|
{
|
|
let header_size = 22;
|
|
let bytes_between_magic_and_comment_size = header_size - 6;
|
|
let file_length = try!(reader.seek(io::SeekFrom::End(0))) as i64;
|
|
|
|
let search_upper_bound = ::std::cmp::max(0, file_length - header_size - ::std::u16::MAX as i64);
|
|
for pos in (file_length - header_size .. search_upper_bound - 1).step_by(-1)
|
|
{
|
|
try!(reader.seek(io::SeekFrom::Start(pos as u64)));
|
|
if try!(reader.read_u32::<LittleEndian>()) == CENTRAL_DIRECTORY_END_SIGNATURE
|
|
{
|
|
try!(reader.seek(io::SeekFrom::Current(bytes_between_magic_and_comment_size)));
|
|
let comment_length = try!(reader.read_u16::<LittleEndian>()) as i64;
|
|
if file_length - pos - header_size == comment_length
|
|
{
|
|
try!(reader.seek(io::SeekFrom::Start(pos as u64)));
|
|
return CentralDirectoryEnd::parse(reader);
|
|
}
|
|
}
|
|
}
|
|
Err(ZipError::InvalidArchive("Could not find central directory end"))
|
|
}
|
|
|
|
pub fn write<T: Write>(&self, writer: &mut T) -> ZipResult<()>
|
|
{
|
|
try!(writer.write_u32::<LittleEndian>(CENTRAL_DIRECTORY_END_SIGNATURE));
|
|
try!(writer.write_u16::<LittleEndian>(self.disk_number));
|
|
try!(writer.write_u16::<LittleEndian>(self.disk_with_central_directory));
|
|
try!(writer.write_u16::<LittleEndian>(self.number_of_files_on_this_disk));
|
|
try!(writer.write_u16::<LittleEndian>(self.number_of_files));
|
|
try!(writer.write_u32::<LittleEndian>(self.central_directory_size));
|
|
try!(writer.write_u32::<LittleEndian>(self.central_directory_offset));
|
|
try!(writer.write_u16::<LittleEndian>(self.zip_file_comment.len() as u16));
|
|
try!(writer.write_all(&self.zip_file_comment));
|
|
Ok(())
|
|
}
|
|
}
|