Finished work (theoretically) on single threaded extraction

Started work on Multi-threaded extraction
Added decompression cache.
Added XattrTable

build.zig

@@ -15,6 +15,7 @@ pub fn build(b: *std.Build) !void {
     const build_options = b.addOptions();
     build_options.addOption(bool, "use_zig_decomp", use_zig_decomp);
     build_options.addOption(bool, "allow_lzo", allow_lzo);
+    build_options.addOption(std.SemanticVersion, "version", version);
 
     const c = b.addTranslateC(.{
         .optimize = optimize,
@@ -79,6 +80,7 @@ pub fn build(b: *std.Build) !void {
             .valgrind = debug,
             .imports = &.{
                 .{ .name = "squashfs", .module = lib.root_module },
+                .{ .name = "build_options", .module = build_options.createModule() },
             },
         }),
     });

src/bin/unsquashfs.zig

@@ -1,9 +1,10 @@
 const std = @import("std");
-const Writer = std.Io.Writer;
+const Io = std.Io;
+const Writer = Io.Writer;
 const builtin = @import("builtin");
+const build = @import("build_options");
 
-const config = @import("config");
-const squashfs = @import("zig_squashfs");
+const squashfs = @import("squashfs");
 
 //TODO: Add more options
 const help_mgs =
@@ -30,7 +31,7 @@ const help_mgs =
 const errors = error{InvalidArguments};
 
 var archive: []const u8 = "";
-var extLoc: []const u8 = "squashfs-root";
+var ext_loc: []const u8 = "squashfs-root";
 var offset: u64 = 0;
 var threads: u32 = 0;
 var verbose: bool = false;
@@ -38,35 +39,48 @@ var ignore_xattrs: bool = false;
 var ignore_permissions: bool = false;
 var force: bool = false;
 
-pub fn main() !void {
-    const alloc = std.heap.smp_allocator;
-    var stdout = std.fs.File.stdout();
-    var out = stdout.writer(&[0]u8{});
+pub fn main(init: std.process.Init) !void {
+    const io = init.io;
+    const alloc = init.alloc;
+
+    var stdout = Io.File.stdout();
+    var out = stdout.writer(io, &[0]u8{});
     defer out.interface.flush() catch {};
-    try handleArgs(alloc, &out.interface);
+
+    try handleArgs(init.minimal.args, &out.interface);
     if (archive.len == 0) {
         try out.interface.print("You must provide a squashfs archive\n", .{});
         try out.interface.print(help_mgs, .{});
         return;
     }
-    var fil: std.fs.File = try std.fs.cwd().openFile(archive, .{}); //TODO: Handle error gracefully.
+    var fil = try Io.Dir.cwd().openFile(io, archive, .{}); //TODO: Handle error gracefully.
     defer fil.close();
-    var arc: squashfs.Archive = try .init(alloc, fil, offset); //TODO: Update when memory size matters. //TODO: Handle error gracefully.
+    var arc: squashfs.Archive = try .init(io, fil, offset); //TODO: Update when memory size matters. //TODO: Handle error gracefully.
     defer arc.deinit();
     const options: squashfs.ExtractionOptions = .{
-        .threads = if (threads == 0) try std.Thread.getCpuCount() else threads,
+        .single_threaded = threads == 1,
         .verbose = verbose,
         .verbose_writer = if (verbose) &out.interface else null,
         .ignore_xattr = ignore_xattrs,
         .ignore_permissions = ignore_permissions,
     };
     if (force)
-        try std.fs.cwd().deleteTree(extLoc);
-    try arc.extract(alloc, extLoc, options); //TODO: Handle error gracefully.
+        try std.fs.cwd().deleteTree(ext_loc);
+    if (threads > 1) {
+        var limited_io = Io.Threaded.init(alloc, .{
+            .argv0 = .init(init.minimal.args),
+            .async_limit = threads,
+            .concurrent_limit = threads,
+            .environ = init.minimal.environ,
+        });
+        try arc.extract(alloc, limited_io.io(), ext_loc, options); //TODO: Handle error gracefully.
+    } else {
+        try arc.extract(alloc, io, ext_loc, options); //TODO: Handle error gracefully.
+    }
 }
 
-fn handleArgs(alloc: std.mem.Allocator, out: *Writer) !void {
-    var args = try std.process.argsWithAllocator(alloc);
+fn handleArgs(main_args: std.process.Args, out: *Writer) !void {
+    var args = main_args.iterate();
     defer args.deinit();
     _ = args.next(); // args[0] is the application launch command.
     while (args.next()) |arg| {
@@ -87,7 +101,7 @@ fn handleArgs(alloc: std.mem.Allocator, out: *Writer) !void {
                 try out.print("-d must be followed by a location\n", .{});
                 return errors.InvalidArguments;
             }
-            extLoc = nxt.?;
+            ext_loc = nxt.?;
             continue;
         } else if (std.mem.eql(u8, arg, "-p")) {
             const nxt = args.next();
@@ -114,7 +128,7 @@ fn handleArgs(alloc: std.mem.Allocator, out: *Writer) !void {
             continue;
         } else if (std.mem.eql(u8, arg, "--version")) {
             try out.print("zig-unsquashfs v", .{});
-            try config.version.format(out);
+            try build.version.format(out);
             try out.print("\nBuilt using Zig {s} in {} mode\n", .{ builtin.zig_version_string, builtin.mode });
             std.process.exit(0);
             return;

src/data/extractor.zig

@@ -3,6 +3,7 @@ const Io = std.Io;
 
 const Decomp = @import("../decomp.zig");
 const DataBlock = @import("../inode.zig").DataBlock;
+const Cache = @import("../util/cache.zig");
 
 const Extractor = @This();
 
@@ -18,6 +19,8 @@ size: u64,
 frag_data: ?[]u8 = null,
 frag_offset: u32 = 0,
 
+cache: ?Cache = null,
+
 pub fn init(data: []u8, decomp: Decomp.Fn, block_size: u32, blocks: []DataBlock, start: u64, size: u64) Extractor {
     return .{
         .data = data,
@@ -34,6 +37,9 @@ pub fn addFrag(self: *Extractor, frag_data: []u8, frag_offset: u32) void {
     self.frag_data = frag_data;
     self.frag_offset = frag_offset;
 }
+pub fn addCache(self: *Extractor, cache: Cache) void {
+    self.cache = cache;
+}
 
 pub fn extractAsync(self: Extractor, alloc: std.mem.Allocator, io: Io, file: Io.File) Error!void {
     if (self.size == 0) return;
@@ -86,10 +92,20 @@ fn blockThread(self: Extractor, alloc: std.mem.Allocator, map_data: []u8, read_o
         return;
     }
 
-    _ = self.decomp(alloc, data, map_data[offset..][0..size]) catch |inner_err| {
-        err.* = inner_err;
-        return;
-    };
+    if (self.cache != null) {
+        const decomp_block = self.cache.?.get(read_offset, block.size) catch |inner_err| {
+            switch (inner_err) {
+                error.Canceled => return error.Canceled,
+                else => |e| err.* = e,
+            }
+            return;
+        };
+        @memcpy(map_data[offset..][0..size], decomp_block[0..size]);
+    } else {
+        _ = self.decomp(alloc, data, map_data[offset..][0..size]) catch |inner_err| {
+            err.* = inner_err;
+        };
+    }
 }
 fn fragThread(self: Extractor, map_data: []u8) error{Canceled}!void {
     const size = self.size % self.block_size;
@@ -100,4 +116,4 @@ fn fragThread(self: Extractor, map_data: []u8) error{Canceled}!void {
 
 // Types
 
-const Error = Io.File.WritePositionalError || Io.File.MemoryMap.CreateError || Decomp.Error;
+pub const Error = Io.File.WritePositionalError || Io.File.MemoryMap.CreateError || Decomp.Error || Cache.Error;

src/data/reader.zig

@@ -3,6 +3,7 @@ const Io = std.Io;
 
 const Decomp = @import("../decomp.zig");
 const DataBlock = @import("../inode.zig").DataBlock;
+const Cache = @import("../util/cache.zig");
 
 const Reader = @This();
 
@@ -23,6 +24,8 @@ sparse_block: bool = false,
 frag_data: ?[]u8 = null,
 frag_offset: u32 = 0,
 
+cache: ?Cache = null,
+
 block: [1024 * 1024]u8 = undefined,
 
 interface: Io.Reader = .{
@@ -55,6 +58,9 @@ pub fn addFrag(self: *Reader, frag_data: []u8, frag_offset: u32) void {
     self.frag_data = frag_data;
     self.frag_offset = frag_offset;
 }
+pub fn addCache(self: *Reader, cache: Cache) void {
+    self.cache = cache;
+}
 
 fn advance(self: *Reader) Io.Reader.Error!void {
     if (self.block_idx > self.blocks.len) return error.EndOfStream;
@@ -98,9 +104,14 @@ fn advance(self: *Reader) Io.Reader.Error!void {
         return;
     }
 
-    _ = self.decomp(self.alloc, self.data[self.offset..][0..block.size], self.block[0..size]) catch return error.ReadFailed;
-    self.interface.buffer = self.block[0..size];
-    self.interface.end = size;
+    if (self.cache == null) {
+        _ = self.decomp(self.alloc, self.data[self.offset..][0..block.size], self.block[0..size]) catch return error.ReadFailed;
+        self.interface.buffer = self.block[0..size];
+        self.interface.end = size;
+    } else {
+        self.interface.buffer = self.cache.?.get(self.io, self.offset, block.size) catch return error.ReadFailed;
+        self.interface.end = self.interface.buffer.len;
+    }
 }
 
 fn stream(r: *Io.Reader, w: *Io.Writer, limit: Io.Limit) Io.Reader.StreamError!usize {

src/directory.zig

@@ -58,6 +58,8 @@ pub fn deinit(self: Directory, alloc: std.mem.Allocator) void {
 
 // Types
 
+pub const Error = error{OutOfMemory} || Reader.Error;
+
 pub const Entry = struct {
     name: []const u8,
     block_start: u32,

src/extract-multi.zig

@@ -1,11 +1,15 @@
 const std = @import("std");
 const Io = std.Io;
 
+const DataExtractor = @import("data/extractor.zig");
 const Decomp = @import("decomp.zig");
+const Directory = @import("directory.zig");
 const ExtractionOptions = @import("options.zig");
 const Inode = @import("inode.zig");
 const Lookup = @import("lookup.zig");
+const MetadataReader = @import("meta_rdr.zig");
 const Superblock = @import("archive.zig").Superblock;
+const Cache = @import("util/cache.zig");
 const XattrTable = @import("xattr.zig");
 
 pub fn extract(
@@ -17,16 +21,204 @@ pub fn extract(
     inode: Inode,
     ext_loc: []const u8,
     options: ExtractionOptions,
-) !void {}
+) !void {
+    const path = std.mem.trim(ext_loc, "/");
 
-pub fn extractReal(
+    var id_table: Lookup.Table(u16) = .init(alloc, data, decomp, super.id_start, super.id_count);
+    defer id_table.deinit();
+
+    var xattr_table: XattrTable = .init(alloc, data, decomp, super.xattr_start);
+    defer xattr_table.deinit();
+
+    var buf: [150]ReturnUnion = undefined;
+    var sel: Io.Select(ReturnUnion) = .init(io, &buf);
+    defer while (sel.cancel()) |res|
+        switch (res) {
+            .path => |p| {
+                const path_return = p catch continue;
+                if (path_return.path.len != path.len)
+                    alloc.free(path_return.path);
+            },
+            else => {},
+        };
+
+    var loop = io.async(io, finishLoop, .{ alloc, io, &sel, &id_table, &xattr_table, options });
+
+    var cache: Cache = .init(alloc, data, decomp);
+    defer cache.deinit();
+
+    var frag_table: Lookup.Table(Lookup.FragEntry) = .init(alloc, data, decomp, super.frag_start, super.frag_count);
+    defer frag_table.deinit();
+
+    switch (inode.hdr.type) {
+        .file, .ext_file => try sel.async(
+            .path,
+            extractFile,
+            .{ alloc, io, data, decomp, &cache, &frag_table, inode, path, true },
+        ),
+        .dir, .ext_dir => try sel.async(
+            .path,
+            extractDir,
+            .{ alloc, io, super, data, decomp, &sel, &cache, &frag_table, inode, path, true },
+        ),
+        .symlink, .ext_symlink => try sel.async(
+            .void,
+            extractSymlink,
+            .{ alloc, io, inode, path, true },
+        ),
+        else => try sel.async(
+            .path,
+            extractNod,
+            .{ alloc, io, inode, path, true },
+        ),
+    }
+
+    try loop.await(io);
+}
+
+fn finishLoop(alloc: std.mem.Allocator, io: Io, id_table: *Lookup.Table(u16), xattr_table: *XattrTable, options: ExtractionOptions) !void {}
+
+fn extractFile(
+    alloc: std.mem.Allocator,
+    io: Io,
+    data: []u8,
+    decomp: Decomp.Fn,
+    cache: *Cache,
+    frag_table: *Lookup.Table(Lookup.FragEntry),
+    inode: Inode,
+    path: []const u8,
+    origin: bool,
+) Error!PathReturn {
+    defer if (!origin) inode.deinit(alloc);
+    errdefer alloc.free(path);
+
+    try io.checkCancel();
+
+    var ret: PathReturn = .{
+        .hdr = inode.hdr,
+        .path = path,
+    };
+
+    var ext: DataExtractor = switch (inode.data) {
+        .file => |f| blk: {
+            var rdr: DataExtractor = .init(data, decomp, super.block_size, f.blocks, f.size, f.block_start);
+            rdr.addCache(cache);
+
+            if (f.frag_idx == 0xFFFFFFFF) break :blk rdr;
+
+            const entry: Lookup.FragEntry = try frag_table.get(io, f.frag_idx);
+            if (entry.size.uncompressed) {
+                rdr.addFrag(data[entry.block_start..][0..entry.size.size]);
+            } else {
+                rdr.addFrag(try cache.get(io, entry.block_start, entry.size));
+            }
+        },
+        .ext_file => |f| blk: {
+            if (f.xattr_idx != 0xFFFFFFFF) ret.xattr_idx = f.xattr_idx;
+
+            var rdr: DataExtractor = .init(data, decomp, super.block_size, f.blocks, f.size, f.block_start);
+            rdr.addCache(cache);
+
+            if (f.frag_idx == 0xFFFFFFFF) break :blk rdr;
+
+            const entry: Lookup.FragEntry = try frag_table.get(io, f.frag_idx);
+            if (entry.size.uncompressed) {
+                rdr.addFrag(data[entry.block_start..][0..entry.size.size]);
+            } else {
+                rdr.addFrag(try cache.get(io, entry.block_start, entry.size));
+            }
+        },
+        else => unreachable,
+    };
+
+    var atomic = try Io.Dir.cwd().createFileAtomic(io, path, .{});
+    defer atomic.deinit(io);
+
+    try ext.extractAsync(alloc, io, atomic.file);
+
+    try atomic.link(io);
+
+    return ret;
+}
+fn extractDir(
     alloc: std.mem.Allocator,
     io: Io,
     super: Superblock,
     data: []u8,
     decomp: Decomp.Fn,
-    frag_table: Lookup.Table(u64),
+    sel: *Io.Select(ReturnUnion),
+    cache: *Cache,
+    frag_table: *Lookup.Table(Lookup.FragEntry),
     inode: Inode,
-    ext_loc: []const u8,
-    options: ExtractionOptions,
-) !void {}
+    path: []const u8,
+    origin: bool,
+) Error!PathReturn {
+    defer if (!origin) inode.deinit(alloc);
+    errdefer alloc.free(path);
+
+    var ret: PathReturn = .{
+        .hdr = inode.hdr,
+        .path = path,
+    };
+
+    try Io.Dir.cwd().createDirPath(io, path);
+
+    var dir: Directory = switch (inode.data) {
+        .dir => |d| blk: {
+            var meta: MetadataReader = .init(alloc, data, decomp, d.block_start);
+            try meta.interface.discardAll(d.block_offset);
+
+            break :blk Directory.init(alloc, &meta.interface, d.size);
+        },
+        .ext_dir => |d| blk: {
+            if (d.xattr_idx != 0xFFFFFFFF) ret.xattr_idx = d.xattr_idx;
+
+            var meta: MetadataReader = .init(alloc, data, decomp, d.block_start);
+            try meta.interface.discardAll(d.block_offset);
+
+            break :blk Directory.init(alloc, &meta.interface, d.size);
+        },
+        else => unreachable,
+    };
+    defer dir.deinit(alloc);
+
+    for (dir.entries) |entry| {
+        var new_inode: Inode = try .initEntry(alloc, data, decomp, super.inode_start, super.block_size, entry);
+
+        const new_path = std.mem.concat(alloc, &.{ path, "/", entry.name }) catch |err| {
+            new_inode.deinit(alloc);
+            return err;
+        };
+
+        sel.async();
+    }
+}
+fn extractSymlink(alloc: std.mem.Allocator, io: Io, inode: Inode, path: []const u8, origin: bool) Error!void {
+    defer if (!origin) {
+        inode.deinit(alloc);
+        alloc.free(path);
+    };
+
+    const target = switch (inode.data) {
+        .symlink => |s| s.target,
+        .ext_symlink => |s| s.target,
+        else => unreachable,
+    };
+    try Io.Dir.cwd().symLink(io, target, path, .{});
+}
+
+// Types
+
+const ReturnUnion = union(enum) {
+    path: Error!PathReturn,
+    dir: Error!PathReturn,
+    void: Error!void,
+};
+
+const Error = error{} || Decomp.Error || Directory.Error || DataExtractor.Error;
+
+const PathReturn = struct {
+    hdr: Inode.Header,
+    path: []const u8,
+    xattr_idx: ?u32 = null,
+};

src/extract-single.zig

@@ -1,11 +1,15 @@
 const std = @import("std");
 const Io = std.Io;
 
+const DataReader = @import("data/reader.zig");
 const Decomp = @import("decomp.zig");
+const Directory = @import("directory.zig");
 const ExtractionOptions = @import("options.zig");
 const Inode = @import("inode.zig");
 const Lookup = @import("lookup.zig");
+const MetadaReader = @import("meta_rdr.zig");
 const Superblock = @import("archive.zig").Superblock;
+const Cache = @import("util/cache.zig");
 const XattrTable = @import("xattr.zig");
 
 pub fn extract(
@@ -17,7 +21,37 @@ pub fn extract(
     inode: Inode,
     ext_loc: []const u8,
     options: ExtractionOptions,
-) !void {}
+) !void {
+    const path = std.mem.trim(ext_loc, "/");
+
+    var cache: Cache = .init(alloc, data, decomp);
+    defer cache.deinit();
+
+    var frag_table: Lookup.Table(Lookup.FragEntry) = .init(alloc, data, decomp, super.frag_start, super.frag_count);
+    defer frag_table.deinit();
+
+    var id_table: Lookup.Table(u16) = .init(alloc, data, decomp, super.id_start, super.id_count);
+    defer id_table.deinit();
+
+    var xattr_table: XattrTable = .init(alloc, data, decomp, super.xattr_start);
+    defer xattr_table.deinit();
+
+    return extractReal(
+        alloc,
+        io,
+        super,
+        data,
+        decomp,
+        &cache,
+        &frag_table,
+        &id_table,
+        &xattr_table,
+        inode,
+        path,
+        options,
+        true,
+    );
+}
 
 pub fn extractReal(
     alloc: std.mem.Allocator,
@@ -25,10 +59,171 @@ pub fn extractReal(
     super: Superblock,
     data: []u8,
     decomp: Decomp.Fn,
-    frag_table: Lookup.Table(u64),
-    id_table: Lookup.Table(u16),
-    xattr_table: XattrTable,
+    cache: *Cache,
+    frag_table: *Lookup.Table(Lookup.FragEntry),
+    id_table: *Lookup.Table(u16),
+    xattr_table: *XattrTable,
     inode: Inode,
-    ext_loc: []const u8,
+    path: []const u8,
     options: ExtractionOptions,
-) !void {}
+    origin: bool,
+) !void {
+    defer if (!origin) {
+        alloc.free(path);
+        inode.deinit(alloc);
+    };
+
+    var xattr_idx: ?u32 = null;
+
+    switch (inode.data) {
+        .dir, .ext_dir => {
+            try Io.Dir.cwd().createDirPath(io, path);
+
+            var dir: Directory = switch (inode.data) {
+                .dir => |d| blk: {
+                    var meta: MetadaReader = .init(alloc, data, decomp, d.block_start);
+                    try meta.interface.discardAll(d.block_offset);
+
+                    break :blk Directory.init(alloc, &meta.interface, d.size);
+                },
+                .ext_dir => |d| blk: {
+                    if (d.xattr_idx != 0xFFFFFFFF) xattr_idx = d.xattr_idx;
+
+                    var meta: MetadaReader = .init(alloc, data, decomp, d.block_start);
+                    try meta.interface.discardAll(d.block_offset);
+
+                    break :blk Directory.init(alloc, &meta.interface, d.size);
+                },
+                else => unreachable,
+            };
+            defer dir.deinit(alloc);
+
+            for (dir.entries) |entry| {
+                var new_inode: Inode = try .initEntry(alloc, data, decomp, super.inode_start, super.block_size, entry);
+
+                const new_path = std.mem.concat(alloc, &.{ path, "/", entry.name }) catch |err| {
+                    new_inode.deinit(alloc);
+                    return err;
+                };
+
+                try extractReal(alloc, io, super, data, decomp, cache, frag_table, id_table, xattr_table, new_inode, new_path, options, false);
+            }
+        },
+        .file, .ext_file => {
+            var rdr: DataReader = switch (inode.data) {
+                .file => |f| blk: {
+                    var rdr: DataReader = .init(alloc, data, decomp, super.block_size, f.blocks, f.size, f.block_start);
+                    rdr.addCache(cache);
+
+                    if (f.frag_idx == 0xFFFFFFFF) break :blk rdr;
+
+                    const entry: Lookup.FragEntry = try frag_table.get(io, f.frag_idx);
+                    if (entry.size.uncompressed) {
+                        rdr.addFrag(data[entry.block_start..][0..entry.size.size]);
+                    } else {
+                        rdr.addFrag(try cache.get(io, entry.block_start, entry.size));
+                    }
+                },
+                .ext_file => |f| blk: {
+                    if (f.xattr_idx != 0xFFFFFFFF) xattr_idx = f.xattr_idx;
+
+                    var rdr: DataReader = .init(alloc, data, decomp, super.block_size, f.blocks, f.size, f.block_start);
+                    rdr.addCache(cache);
+
+                    if (f.frag_idx == 0xFFFFFFFF) break :blk rdr;
+
+                    const entry: Lookup.FragEntry = try frag_table.get(io, f.frag_idx);
+                    if (entry.size.uncompressed) {
+                        rdr.addFrag(data[entry.block_start..][0..entry.size.size]);
+                    } else {
+                        rdr.addFrag(try cache.get(io, entry.block_start, entry.size));
+                    }
+                },
+                else => unreachable,
+            };
+
+            var atomic = try Io.Dir.cwd().createFileAtomic(io, path, .{});
+            defer atomic.deinit(io);
+
+            var writer = atomic.file.writer(io, &[0]u8{});
+            _ = try rdr.interface.streamRemaining(&writer.interface);
+            try writer.flush();
+
+            try atomic.link(io);
+        },
+        .symlink => |s| return Io.Dir.cwd().symLink(io, s.target, path, .{}),
+        .ext_symlink => |s| return Io.Dir.cwd().symLink(io, s.target, path, .{}),
+        else => {
+            var dev: u32 = 0;
+            var mode: u32 = undefined;
+
+            const DT = std.posix.DT;
+
+            switch (inode.data) {
+                .char_dev => |d| {
+                    dev = d.device;
+                    mode = DT.CHR;
+                },
+                .block_dev => |d| {
+                    dev = d.device;
+                    mode = DT.BLK;
+                },
+                .ext_char_dev => |d| {
+                    if (d.xattr_idx != 0xFFFFFFFF) xattr_idx = d.xattr_idx;
+
+                    dev = d.device;
+                    mode = DT.CHR;
+                },
+                .ext_block_dev => |d| {
+                    if (d.xattr_idx != 0xFFFFFFFF) xattr_idx = d.xattr_idx;
+
+                    dev = d.device;
+                    mode = DT.BLK;
+                },
+                .fifo => mode = DT.FIFO,
+                .socket => mode = DT.SOCK,
+                .ext_fifo => |i| {
+                    if (i.xattr_idx != 0xFFFFFFFF) xattr_idx = i.xattr_idx;
+
+                    mode = DT.FIFO;
+                },
+                .ext_socket => |i| {
+                    if (i.xattr_idx != 0xFFFFFFFF) xattr_idx = i.xattr_idx;
+
+                    mode = DT.SOCK;
+                },
+                else => unreachable,
+            }
+
+            const sentinel_path = try alloc.dupeSentinel(u8, path, 0);
+            defer alloc.free(sentinel_path);
+
+            const res = std.os.linux.mknod(sentinel_path, mode, dev);
+            if (res != 0)
+                return error.MknodError;
+        },
+    }
+
+    if (options.ignore_permissions and (options.ignore_xattr or xattr_idx == null)) return;
+
+    var fil: Io.File = try Io.Dir.cwd().openFile(io, path, .{});
+    defer fil.close(io);
+
+    if (!options.ignore_permissions) {
+        try fil.setTimestamps(io, .{
+            .modify_timestamp = .init(Io.Timestamp.fromNanoseconds(@as(i96, @intCast(inode.hdr.mod_time)) * std.time.ns_per_s)),
+        });
+        try fil.setPermissions(io, @enumFromInt(inode.hdr.permissions));
+        try fil.setOwner(io, try id_table.get(io, inode.hdr.uid_idx), try id_table.get(io, inode.hdr.gid_idx));
+    }
+    if (!options.ignore_xattr and xattr_idx != null) {
+        const xattr = try xattr_table.get(alloc, io, xattr_idx.?);
+        defer xattr.deinit(alloc);
+
+        for (xattr.kvs) |kv| {
+            const res = std.os.linux.fsetxattr(fil.handle, kv.key, kv.value, kv.value.len, 0);
+            if (res != 0)
+                return error.SetXattrError;
+        }
+    }
+}

src/lookup.zig

@@ -1,6 +1,7 @@
 const std = @import("std");
 const Io = std.Io;
 
+const DataBlock = @import("inode.zig").DataBlock;
 const Decomp = @import("decomp.zig");
 const MetadataReader = @import("meta_rdr.zig");
 const ProtectedMap = @import("util/protected_map.zig");
@@ -57,3 +58,11 @@ pub fn Table(comptime T: anytype) type {
         }
     };
 }
+
+// Types
+
+pub const FragEntry = extern struct {
+    block_start: u64,
+    size: DataBlock,
+    _: u32,
+};

src/util/cache.zig

@@ -0,0 +1,52 @@
+const std = @import("std");
+const Io = std.Io;
+
+const Decomp = @import("../decomp.zig");
+
+const CacheMap = @import("protected_map.zig").ProtectedMap(u64, CachedBlock, decompressBlock);
+
+const Cache = @This();
+
+alloc: std.mem.Allocator,
+
+data: []u8,
+decomp: Decomp.Fn,
+
+cache: CacheMap,
+
+pub fn init(alloc: std.mem.Allocator, data: []u8, decomp: Decomp.Fn) Cache {
+    return .{
+        .alloc = alloc,
+
+        .data = data,
+        .decomp = decomp,
+
+        .cache = .init(alloc),
+    };
+}
+pub fn deinit(self: *Cache) void {
+    self.cache.deinit();
+}
+
+pub fn get(self: *Cache, io: Io, offset: u64, compressed_size: u32) Error![]u8 {
+    const res: CachedBlock = try self.cache.getOrPut(io, offset, .{ self.alloc, self.data, self.decomp, offset, compressed_size });
+    return res.block[0..res.size];
+}
+
+fn decompressBlock(alloc: std.mem.Allocator, data: []u8, decomp: Decomp.Fn, offset: u64, compressed_size: u32) !CachedBlock {
+    const block = data[offset..][0..compressed_size];
+    var new_cache: CachedBlock = undefined;
+
+    new_cache.size = @truncate(try decomp(alloc, block, &new_cache.block));
+
+    return new_cache;
+}
+
+// Types
+
+pub const Error = CacheMap.Error;
+
+const CachedBlock = struct {
+    block: [1024 * 1024]u8,
+    size: u32,
+};

src/util/protected_map.zig

@@ -28,7 +28,7 @@ pub fn ProtectedMap(comptime K: anytype, comptime T: anytype, comptime create_fn
             self.map.deinit();
         }
 
-        pub fn getOrPut(self: *Map, io: Io, key: K, create_fn_args: std.meta.ArgsTuple(create_fn)) !*T {
+        pub fn getOrPut(self: *Map, io: Io, key: K, create_fn_args: std.meta.ArgsTuple(create_fn)) Error!*T {
             {
                 try self.mut.lockShared(io);
                 defer self.mut.unlockShared(io);
@@ -70,6 +70,9 @@ pub fn ProtectedMap(comptime K: anytype, comptime T: anytype, comptime create_fn
 
         // Map Types
 
+        pub const Error = error{ Canceled, OutOfMemory } ||
+            if (@TypeOf(CreateError) == void) error{} else CreateError;
+
         const CreateError: type = switch (@typeInfo(@typeInfo(create_fn).@"fn".return_type)) {
             .error_union => |e| e.error_set,
             else => void,

src/xattr.zig

@@ -1,3 +1,132 @@
 const std = @import("std");
+const Io = std.Io;
+
+const Decomp = @import("decomp.zig");
+const Lookup = @import("lookup.zig");
+const MetadataReader = @import("meta_rdr.zig");
+const Ref = @import("inode.zig").Ref;
 
 const XattrTable = @This();
+
+table_start: u64,
+
+table: Lookup.Table(Entry),
+
+pub fn init(alloc: std.mem.Allocator, data: []u8, decomp: Decomp.Fn, table_start: u64) XattrTable {
+    const start = std.mem.readInt(u64, data[table_start..][0..8], .little);
+    const table_num = std.mem.readInt(u32, data[table_start + 8 ..][0..4], .little);
+
+    return .{
+        .table_start = start,
+        .table = .init(alloc, data, decomp, table_start + 16, table_num),
+    };
+}
+pub fn deinit(self: *XattrTable) void {
+    self.table.deinit();
+}
+
+pub fn get(self: *XattrTable, alloc: std.mem.Allocator, io: Io, idx: u32) !Xattr {
+    const entry: Entry = try self.table.get(io, idx);
+
+    const out: std.ArrayList(KeyValue) = try .initCapacity(alloc, entry.count);
+    errdefer {
+        for (out.items) |kv|
+            kv.deinit(alloc);
+        out.deinit(alloc);
+    }
+
+    var meta: MetadataReader = .init(alloc, self.table.data, self.table.decomp, self.table_start + entry.ref.block_start);
+    try meta.interface.discardAll(entry.ref.block_offset);
+
+    for (0..entry.count) |_| {
+        var key_entry: KeyEntry = undefined;
+
+        try meta.interface.readSliceEndian(KeyEntry, @ptrCast(&key_entry), .little);
+
+        const prefix = switch (key_entry.type.type) {
+            .user => "user.",
+            .trusted => "trusted.",
+            .security => "security.",
+        };
+
+        const key = try alloc.allocSentinel(u8, key_entry.name_size + prefix.len, 0);
+        errdefer alloc.free(key);
+
+        @memcpy(key[0..prefix.len], prefix);
+
+        try meta.interface.readSliceEndian(u8, key[prefix.len..][0..key_entry.name_size], .little);
+
+        const value = if (key_entry.type.out_of_line) blk: {
+            try meta.interface.discardAll(4);
+
+            var ref: Ref = undefined;
+            try meta.interface.readSliceEndian(Ref, @ptrCast(&ref), .little);
+
+            var value_meta: MetadataReader = .init(alloc, self.table.data, self.table.decomp, self.table_start + ref.block_start);
+            try value_meta.interface.discardAll(ref.block_offset);
+
+            break :blk try readValue(alloc, &value_meta.interface);
+        } else try readValue(alloc, &meta.interface);
+
+        const ptr = out.addOneAssumeCapacity();
+
+        ptr.* = .{
+            .key = key,
+            .value = value,
+        };
+    }
+}
+
+fn readValue(alloc: std.mem.Allocator, rdr: *Io.Reader) ![]u8 {
+    var size: u32 = undefined;
+    try rdr.readSliceEndian(u32, @ptrCast(&size), .little);
+
+    const value = try alloc.alloc(u8, size);
+    errdefer alloc.free(value);
+
+    try rdr.readSliceEndian(u8, value, .little);
+
+    return value;
+}
+
+// Types
+
+const Xattr = struct {
+    kvs: []KeyValue,
+
+    pub fn deinit(self: Xattr, alloc: std.mem.Allocator) void {
+        for (self.kvs) |kv|
+            kv.deinit(alloc);
+
+        alloc.free(self.kvs);
+    }
+};
+
+const KeyValue = struct {
+    key: [:0]const u8,
+    value: []const u8,
+
+    pub fn deinit(self: KeyValue, alloc: std.mem.Allocator) void {
+        alloc.free(self.key);
+        alloc.free(self.value);
+    }
+};
+
+const KeyEntry = extern struct {
+    type: packed struct(u16) {
+        type: enum(u8) {
+            user,
+            trusted,
+            security,
+        },
+        out_of_line: bool,
+        _: u7,
+    },
+    name_size: u16,
+};
+
+const Entry = extern struct {
+    ref: Ref,
+    count: u32,
+    size: u32,
+};