Started work on xattr table reading

src/table.zig

@@ -5,15 +5,14 @@ const util = @import("utils/util.zig");
 
 const MetadataReader = @import("utils/meta.zig");
 const Decomp = @import("decomp.zig");
+const Reference = @import("inode.zig").Reference;
 
-pub fn Table(comptime T: type) type {
+pub fn Lookup(comptime T: type) type {
     return struct {
         const Self = @This();
 
         const ITEMS_PER_BLOCK = 8192 / @sizeOf(T);
 
-        alloc: std.mem.Allocator,
-
         data: []u8,
         decomp: Decomp.Fn,
 
@@ -33,18 +32,18 @@ pub fn Table(comptime T: type) type {
 
                 .start = start,
                 .count = count,
-                .block_count = std.math.divCeil(u32, count, ITEMS_PER_BLOCK),
+                .block_count = try std.math.divCeil(u32, count, ITEMS_PER_BLOCK),
             };
         }
-        pub fn deinit(self: *Self) void {
+        pub fn deinit(self: *Self, alloc: std.mem.Allocator) void {
             var iter = self.table.valueIterator();
             while (iter.next()) |block|
-                self.alloc.free(block);
+                alloc.free(block);
 
-            self.table.deinit(self.alloc);
+            self.table.deinit(alloc);
         }
 
-        fn getBlock(self: *Self, io: Io, idx: u32) ![]T {
+        fn getBlock(self: *Self, alloc: std.mem.Allocator, io: Io, idx: u32) ![]T {
             const init_get = self.table.get(idx);
             if (init_get != null) return init_get.?;
 
@@ -55,26 +54,104 @@ pub fn Table(comptime T: type) type {
 
             const len = if (idx == self.block_count - 1) self.count % ITEMS_PER_BLOCK else ITEMS_PER_BLOCK;
 
-            const new_block = try self.alloc.alloc(T, len);
-            errdefer self.alloc.free(new_block);
+            const new_block = try alloc.alloc(T, len);
+            errdefer alloc.free(new_block);
 
-            var meta: MetadataReader = .init(self.alloc, self.data[start..], self.decomp);
+            var meta: MetadataReader = .init(alloc, self.data[start..], self.decomp);
 
             try meta.interface.readSliceEndian(T, new_block, .little);
 
-            try self.table.put(self.alloc, idx, new_block);
+            try self.table.put(alloc, idx, new_block);
 
             return new_block;
         }
 
-        pub fn get(self: *Self, io: Io, idx: u32) !T {
+        pub fn get(self: *Self, alloc: std.mem.Allocator, io: Io, idx: u32) !T {
             if (idx >= self.count) return error.InvalidIndex;
 
             const block_idx = idx / ITEMS_PER_BLOCK;
 
-            const block = self.getBlock(io, block_idx);
+            const block = self.getBlock(io, alloc, block_idx);
 
             return block[idx % ITEMS_PER_BLOCK];
         }
     };
 }
+
+pub const Xattr = struct {
+    kv_start: u64,
+    lookup: Lookup(XattrLookup),
+
+    pub fn init(alloc: std.mem.Allocator, data: []u8, decomp: Decomp.Fn, start: u64) !Xattr {
+        const kv_start = util.readValue(u64, data[start..][0..8]);
+        const count = util.readValue(u32, data[start..][8..12]);
+
+        return .{
+            .kv_start = kv_start,
+            .lookup = try .init(alloc, data, decomp, start + 16, count),
+        };
+    }
+    pub fn deinit(self: *Xattr, alloc: std.mem.Allocator) void {
+        self.lookup.deinit(alloc);
+    }
+
+    pub fn get(self: *Xattr, alloc: std.mem.Allocator, io: Io, idx: u32) !KV {
+        const lookup = try self.lookup.get(alloc, io, idx);
+
+        var meta: MetadataReader = .init(alloc, self.lookup.data[self.kv_start + lookup.ref.start ..], self.lookup.decomp);
+        try meta.interface.discardAll(lookup.ref.offset);
+
+        const kvs = try alloc.alloc(KV, lookup.count);
+        errdefer alloc.free(kvs);
+
+        for (kvs) |*kv| {
+            const entry = try util.readValueRdr(KeyEntry, &meta.interface);
+
+            const prefix = switch (entry.type.type) {
+                .user => "user.",
+                .trusted => "trusted.",
+                .security => "security.",
+            };
+
+            kv.name = try alloc.allocSentinel(u8, entry.name_size + prefix.len, 0);
+            errdefer alloc.free(kv.name);
+
+            try meta.interface.readSliceEndian(u8, kv.name[prefix.len..], .little);
+
+            @memcpy(kv.name[0..prefix.len], prefix);
+
+            if (entry.type.out_of_line) {}
+        }
+    }
+
+    //types
+
+    pub const KV = struct {
+        name: [:0]u8,
+        value: []u8,
+
+        pub fn deinit(self: KV, alloc: std.mem.Allocator) void {
+            alloc.free(self.name);
+            alloc.free(self.value);
+        }
+    };
+
+    const XattrLookup = extern struct {
+        ref: Reference,
+        count: u32,
+        size: u32,
+    };
+
+    const KeyEntry = extern struct {
+        type: packed struct(u16) {
+            type: enum(u8) {
+                user,
+                trusted,
+                security,
+            },
+            out_of_line: bool,
+            _: u7,
+        },
+        name_size: u16,
+    };
+};

src/utils/decompress.zig

@@ -7,12 +7,17 @@ const Decomp = @import("../decomp.zig");
 const Directory = @import("../dir.zig");
 const MetadataReader = @import("meta.zig");
 const DataReader = @import("data_reader.zig");
+const Table = @import("../table.zig");
 const Super = @import("../archive.zig").Super;
 
 pub fn single(alloc: std.mem.Allocator, io: Io, data: []const u8, decomp: Decomp.Fn, super: Super, inode: Inode, filepath: []const u8, options: Options) !void {
     const path = std.mem.trim(u8, filepath, "/");
 
-    var pool: std.ArrayList(InodeAndPath) = .initBuffer(&.{.{ .inode = inode, .path = path }});
+    var pool: std.ArrayList(InodeAndPath) = .initBuffer(&.{.{
+        .inode = inode,
+        .path = path,
+        .root = true,
+    }});
     defer {
         while (pool.pop()) |in|
             in.deinit(in);
@@ -55,7 +60,11 @@ pub fn single(alloc: std.mem.Allocator, io: Io, data: []const u8, decomp: Decomp
                         return err;
                     };
 
-                    try pool.append(alloc, .{ .inode = new_inode, .path = new_path });
+                    try pool.append(alloc, .{
+                        .inode = new_inode,
+                        .path = new_path,
+                        .root = false,
+                    });
                 }
 
                 try dirs.append(alloc, in);
@@ -136,13 +145,20 @@ pub fn single(alloc: std.mem.Allocator, io: Io, data: []const u8, decomp: Decomp
         // TODO: apply permissions & xattrs
     }
 }
+pub fn multi() !void {}
+
+// Utils
+
 const InodeAndPath = struct {
     inode: Inode,
     path: []const u8,
+    root: bool,
 
     fn deinit(self: InodeAndPath, alloc: std.mem.Allocator) void {
+        if (self.root) return;
         self.inode.deinit(alloc);
         alloc.free(self.path);
     }
 };
-pub fn multi() !void {}
+
+inline fn applyPermissions(alloc: std.mem.Allocator, io: Io, id_table: Table.Lookup(u16), xattr_table: Table.Xattr, inode: Inode, path: []const u8, options: Options) !void {}