Caleb Gardner
77 lines
2.5 KiB
Zig
77 lines
2.5 KiB
Zig
const std = @import("std");
|
|
const io = std.io;
|
|
|
|
pub const BlockSize = packed struct {
|
|
size: u23,
|
|
not_compressed: bool,
|
|
_: u8,
|
|
};
|
|
|
|
pub const FileInode = struct {
|
|
data_start: u32,
|
|
frag_idx: u32,
|
|
frag_offset: u32,
|
|
size: u32,
|
|
blocks: []const BlockSize,
|
|
|
|
pub fn init(alloc: std.mem.Allocator, rdr: io.AnyReader, block_size: u32) !FileInode {
|
|
var fixed_buf = [1]u8{0} ** 16;
|
|
_ = try rdr.readAll(&fixed_buf);
|
|
const frag_idx = std.mem.bytesToValue(u32, fixed_buf[4..8]);
|
|
const size = std.mem.bytesToValue(u32, fixed_buf[12..16]);
|
|
var block_num = size / block_size;
|
|
if (frag_idx == 0xFFFFFFFF and size % block_size > 0) {
|
|
block_num += 1;
|
|
}
|
|
const blocks = try alloc.alloc(BlockSize, block_num);
|
|
_ = try rdr.readAll(@ptrCast(blocks));
|
|
return .{
|
|
.data_start = std.mem.bytesToValue(u32, fixed_buf[0..4]),
|
|
.frag_idx = frag_idx,
|
|
.frag_offset = std.mem.bytesToValue(u32, fixed_buf[8..12]),
|
|
.size = size,
|
|
.blocks = blocks,
|
|
};
|
|
}
|
|
pub fn deinit(self: FileInode, alloc: std.mem.Allocator) void {
|
|
alloc.free(self.blocks);
|
|
}
|
|
};
|
|
|
|
pub const ExtFileInode = struct {
|
|
data_start: u64,
|
|
size: u64,
|
|
sparse: u64,
|
|
hard_links: u32,
|
|
frag_idx: u32,
|
|
frag_offset: u32,
|
|
xattr_idx: u32,
|
|
blocks: []const BlockSize,
|
|
|
|
pub fn init(alloc: std.mem.Allocator, rdr: io.AnyReader, block_size: u32) !ExtFileInode {
|
|
var fixed_buf = [1]u8{0} ** 40;
|
|
_ = try rdr.readAll(&fixed_buf);
|
|
const size = std.mem.bytesToValue(u64, fixed_buf[8..16]);
|
|
const frag_idx = std.mem.bytesToValue(u32, fixed_buf[28..32]);
|
|
var block_num = size / block_size;
|
|
if (frag_idx == 0xFFFFFFFF and size % block_size > 0) {
|
|
block_num += 1;
|
|
}
|
|
const blocks = try alloc.alloc(BlockSize, block_num);
|
|
_ = try rdr.readAll(@ptrCast(blocks));
|
|
return .{
|
|
.data_start = std.mem.bytesToValue(u64, fixed_buf[0..8]),
|
|
.size = size,
|
|
.sparse = std.mem.bytesToValue(u64, fixed_buf[16..24]),
|
|
.hard_links = std.mem.bytesToValue(u32, fixed_buf[24..28]),
|
|
.frag_idx = frag_idx,
|
|
.frag_offset = std.mem.bytesToValue(u32, fixed_buf[32..36]),
|
|
.xattr_idx = std.mem.bytesToValue(u32, fixed_buf[36..40]),
|
|
.blocks = blocks,
|
|
};
|
|
}
|
|
pub fn deinit(self: ExtFileInode, alloc: std.mem.Allocator) void {
|
|
alloc.free(self.blocks);
|
|
}
|
|
};
|