From 13f92f2e83c7156ff8f42a16559428fdb6f52354 Mon Sep 17 00:00:00 2001
From: Caleb Gardner <calebq23@gmail.com>
Date: Wed, 30 Jul 2025 20:54:11 -0500
Subject: [PATCH] Re-writing data reader. Again.

---
 src/reader/data.zig | 91 ++++++++++++++++++++++++++++++++++++---------
 1 file changed, 74 insertions(+), 17 deletions(-)

diff --git a/src/reader/data.zig b/src/reader/data.zig
index 84b7565..62eee6f 100644
--- a/src/reader/data.zig
+++ b/src/reader/data.zig
@@ -71,23 +71,60 @@ pub fn DataReader(comptime T: type) type {
 
         pub fn writeTo(self: Self, wrt: anytype) !void {
             comptime std.debug.assert(std.meta.hasFn(@TypeOf(wrt), "write") or std.meta.hasFn(@TypeOf(wrt), "pwrite"));
-            var wg: std.Thread.WaitGroup = .{};
-            wg.startMany(self.numBlocks());
             var map: CompletionMap = .init(self.alloc);
             defer map.deinit();
             var mut: std.Thread.Mutex = .{};
             var cond: std.Thread.Condition = .{};
-            std.Thread.spawn(.{ .allocator = self.alloc }, writeThread, .{ self, wrt, &map, &mut, &cond, null, null });
-            for (0..self.numBlocks()) |i| {}
-            wg.wait();
+            var errs: std.ArrayList(anyerror) = .init(self.alloc);
+            defer errs.deinit();
+            var write_thr = try std.Thread.spawn(
+                .{ .allocator = self.alloc },
+                writeThread,
+                .{ self, wrt, &errs, &map, &mut, &cond, null, null },
+            );
+            for (0..self.numBlocks()) |i| {
+                var thr = std.Thread.spawn(
+                    .{ .allocator = self.alloc },
+                    decompThread,
+                    .{ self, i, &errs, &map, &mut, &cond },
+                ) catch |err| {
+                    errs.append(err) catch {};
+                };
+                thr.detach();
+            }
+            write_thr.join();
+            if (errs.items.len > 0) return errs.items[0];
         }
         pub fn writeToNoBlock(self: Self, wrt: anytype, comptime finish: anytype, finish_args: anytype) !void {
             comptime std.debug.assert(std.meta.hasFn(@TypeOf(wrt), "write") or std.meta.hasFn(@TypeOf(wrt), "pwrite"));
-            _ = self;
-            _ = finish;
-            _ = finish_args;
-            return error{TODO}.TODO;
+            var map: CompletionMap = .init(self.alloc);
+            errdefer map.deinit();
+            var mut = try self.alloc.create(std.Thread.Mutex);
+            errdefer self.alloc.destroy(mut);
+            mut.* = .{};
+            var cond = try self.alloc.create(std.Thread.Condition);
+            errdefer self.alloc.destroy(cond);
+            cond.* = .{};
+            var errs: std.ArrayList(anyerror) = .init(self.alloc);
+            errdefer errs.deinit();
+            var write_thr = try std.Thread.spawn(
+                .{ .allocator = self.alloc },
+                writeThread,
+                .{ self, wrt, &errs, &map, &mut, &cond, finish, finish_args },
+            );
+            write_thr.detach();
+            for (0..self.numBlocks()) |i| {
+                var thr = std.Thread.spawn(
+                    .{ .allocator = self.alloc },
+                    decompThread,
+                    .{ self, i, &errs, &map, &mut, &cond },
+                ) catch |err| {
+                    errs.append(err) catch {};
+                };
+                thr.detach();
+            }
         }
+        fn writeToNoBlockFinish(comptime finish: anytype, finish_args: anytype) void {}
 
         fn numBlocks(self: Self) usize {
             var out = self.sizes.len;
@@ -124,6 +161,7 @@ pub fn DataReader(comptime T: type) type {
         fn writeThread(
             self: Self,
             wrt: anytype,
+            errs: *std.ArrayList(anyerror),
             map: *CompletionMap,
             mut: *std.Thread.Mutex,
             cond: *std.Thread.Condition,
@@ -133,7 +171,7 @@ pub fn DataReader(comptime T: type) type {
             var cur_idx: usize = 0;
             mut.lock();
             defer mut.unlock();
-            while (cur_idx < self.numBlocks()) {
+            while (cur_idx < self.numBlocks() and errs.items.len == 0) {
                 cond.wait(mut);
                 if (comptime std.meta.hasFn(@TypeOf(wrt), "pwrite")) {
                     for (map.keys()) |k| {
@@ -141,13 +179,13 @@ pub fn DataReader(comptime T: type) type {
                         defer self.alloc.free(blk);
                         if (blk.len > 0) {
                             _ = wrt.pwrite(map.fetchSwapRemove(k).?.value, self.block_size * k) catch |err| {
-                                std.debug.print("ERROR: {}\n", .{err});
-                                //TODO: handle properly.
+                                errs.append(err) catch {};
+                                break;
                             };
                         } else {
                             _ = wrt.pwrite(&[1]u8{0}, (self.block_size * (k + 1)) - 1) catch |err| {
-                                std.debug.print("ERROR: {}\n", .{err});
-                                //TODO: handle properly.
+                                errs.append(err) catch {};
+                                break;
                             };
                         }
                         cur_idx += 1;
@@ -159,8 +197,14 @@ pub fn DataReader(comptime T: type) type {
                     defer self.alloc.free(blk);
                     if (blk.len > 0) {
                         _ = wrt.write(blk) catch |err| {
-                            std.debug.print("ERROR: {}\n", .{err});
-                            //TODO: handle properly.
+                            errs.append(err) catch {};
+                            break;
+                        };
+                    } else {
+                        const blank: [1024 * 1024]u8 = [1]u8{0} ** (1024 * 1024);
+                        _ = wrt.write(blank[0..self.block_size]) catch |err| {
+                            errs.append(err) catch {};
+                            break;
                         };
                     }
                     cur_idx += 1;
@@ -171,9 +215,22 @@ pub fn DataReader(comptime T: type) type {
         fn decompThread(
             self: Self,
             idx: usize,
+            errs: *std.ArrayList(anyerror),
             map: *CompletionMap,
             mut: *std.Thread.Mutex,
             cond: *std.Thread.Condition,
-        ) void {}
+        ) void {
+            if (errs.items.len > 0) return;
+            const block = self.blockAt(idx) catch |err| {
+                errs.append(err) catch {};
+                return;
+            };
+            mut.lock();
+            defer mut.unlock();
+            map.put(idx, block) catch |err| {
+                errs.append(err) catch {};
+            };
+            cond.signal();
+        }
     };
 }