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Further work on getting everything working again

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Mainly working on decompression interface
This commit is contained in:
Caleb Gardner
2026-04-30 07:00:46 -05:00
parent b67d02074d
commit 274d088490
4 changed files with 106 additions and 17 deletions
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src/lookup_table.zig
+28 -13
View File
@@ -1,9 +1,29 @@
const std = @import("std");
const Io = std.Io;
const Decompressor = @import("util/decompressor.zig");
const OffsetFile = @import("util/offset_file.zig");
const MetadataReader = @import("util/metadata.zig");
pub fn lookupValue(comptime T: anytype, alloc: std.mem.Allocator, io: Io, decomp: *Decompressor, file: OffsetFile, table_start: u64, idx: u16) !T {
const T_PER_BLOCK: u16 = 8192 / @sizeOf(T);
const block = idx / T_PER_BLOCK;
const block_offset = idx % T_PER_BLOCK;
var rdr = try file.readerAt(io, table_start + (8 * block), &[0]u8{});
var offset: u64 = undefined;
try rdr.interface.readSliceEndian(u64, @ptrCast(&offset), .little);
rdr = try file.readerAt(io, offset, &[0]u8{});
var meta: MetadataReader = .init(alloc, &rdr, decomp);
try meta.interface.discardAll(@sizeOf(T) * block_offset);
var out: T = undefined;
try meta.interface.readSliceEndian(T, @ptrCast(&out), .little);
return out;
}
pub fn CachedTable(comptime T: anytype) type {
return struct {
const T_PER_BLOCK: u16 = 8192 / @sizeOf(T);
@@ -11,7 +31,6 @@ pub fn CachedTable(comptime T: anytype) type {
const Table = @This();
alloc: std.mem.Allocator,
io: Io,
fil: OffsetFile,
table_start: u64,
total_num: u32,
@@ -20,10 +39,9 @@ pub fn CachedTable(comptime T: anytype) type {
mut: Io.Mutex = .init,
pub fn init(alloc: std.mem.Allocator, io: Io, fil: OffsetFile, offset: u64, total_num: u32) Table {
pub fn init(alloc: std.mem.Allocator, fil: OffsetFile, offset: u64, total_num: u32) Table {
return .{
.alloc = alloc,
.io = io,
.fil = fil,
.table_start = offset,
.total_num = total_num,
@@ -32,34 +50,31 @@ pub fn CachedTable(comptime T: anytype) type {
};
}
pub fn get(self: *Table, idx: u32) !T {
pub fn get(self: *Table, io: Io, idx: u32) !T {
const block = idx / T_PER_BLOCK;
const block_offset = idx % T_PER_BLOCK;
if (self.table.contains(block))
return self.table.get(block).?[block_offset];
try self.mut.lock(self.io);
defer self.mut.unlock(self.io);
try self.mut.lock(io);
defer self.mut.unlock(io);
if (self.table.contains(block))
return self.table.get(block).?[block_offset];
var rdr = try self.fil.readerAt(self.io, self.table_start + (8 * block), &[0]u8{});
var rdr = try self.fil.readerAt(io, self.table_start + (8 * block), &[0]u8{});
var offset: u64 = undefined;
try rdr.interface.readSliceEndian(u64, @ptrCast(&offset), .little);
const arr_num: u16 = if (self.total_num % T_PER_BLOCK != 0 and block == (self.total_num - 1) / T_PER_BLOCK)
const len: u16 = if (self.total_num % T_PER_BLOCK != 0 and block == (self.total_num - 1) / T_PER_BLOCK)
self.total_num % T_PER_BLOCK
else
T_PER_BLOCK;
rdr = try self.fil.readerAt(self.io, offset, &[0]u8{});
rdr = try self.fil.readerAt(io, offset, &[0]u8{});
var meta: MetadataReader = .init(self.alloc, &rdr, self.decomp);
try self.table.put(
block,
try meta.interface.readSliceEndianAlloc(self.alloc, T, arr_num, .little),
);
try self.table.put(block, try meta.interface.readSliceEndianAlloc(self.alloc, T, len, .little));
}
};
}