Update libxev to version 20252401.0‑31eed4e and apply patches and.

MODULE.bazel

@@ -101,7 +101,7 @@ use_repo(zls, "zls_aarch64-macos", "zls_x86_64-linux")
 
 register_toolchains("//third_party/zls:all")
 
-bazel_dep(name = "libxev", version = "20241208.2-db6a52b")
+bazel_dep(name = "libxev", version = "20252401.0-31eed4e")
 bazel_dep(name = "llvm-raw", version = "20250117.0-bf17016")
 
 llvm = use_extension("@llvm-raw//utils/bazel:extension.bzl", "llvm")

MODULE.bazel.lock

@@ -155,6 +155,7 @@
     "https://bazel-registry.zml.ai/modules/stardoc/0.6.2/MODULE.bazel": "not found",
     "https://bazel-registry.zml.ai/modules/stardoc/0.7.0/MODULE.bazel": "not found",
     "https://bazel-registry.zml.ai/modules/stardoc/0.7.1/MODULE.bazel": "not found",
+    "https://bazel-registry.zml.ai/modules/toolchains_protoc/0.3.7/MODULE.bazel": "not found",
     "https://bazel-registry.zml.ai/modules/upb/0.0.0-20220923-a547704/MODULE.bazel": "not found",
     "https://bazel-registry.zml.ai/modules/upb/0.0.0-20230516-61a97ef/MODULE.bazel": "not found",
     "https://bazel-registry.zml.ai/modules/with_cfg.bzl/0.8.0/MODULE.bazel": "not found",
@@ -354,6 +355,8 @@
     "https://bcr.bazel.build/modules/stardoc/0.7.0/MODULE.bazel": "05e3d6d30c099b6770e97da986c53bd31844d7f13d41412480ea265ac9e8079c",
     "https://bcr.bazel.build/modules/stardoc/0.7.1/MODULE.bazel": "3548faea4ee5dda5580f9af150e79d0f6aea934fc60c1cc50f4efdd9420759e7",
     "https://bcr.bazel.build/modules/stardoc/0.7.1/source.json": "b6500ffcd7b48cd72c29bb67bcac781e12701cc0d6d55d266a652583cfcdab01",
+    "https://bcr.bazel.build/modules/toolchains_protoc/0.3.7/MODULE.bazel": "d2758e5af5838970175274c4fcb67edc8d2f4f8f348885da90c42fafc221236d",
+    "https://bcr.bazel.build/modules/toolchains_protoc/0.3.7/source.json": "07e0eab9be4aded2a8074504a80c55c5a48e811a9824061642af639baaabf985",
     "https://bcr.bazel.build/modules/upb/0.0.0-20220923-a547704/MODULE.bazel": "7298990c00040a0e2f121f6c32544bab27d4452f80d9ce51349b1a28f3005c43",
     "https://bcr.bazel.build/modules/upb/0.0.0-20230516-61a97ef/MODULE.bazel": "c0df5e35ad55e264160417fd0875932ee3c9dda63d9fccace35ac62f45e1b6f9",
     "https://bcr.bazel.build/modules/with_cfg.bzl/0.8.0/MODULE.bazel": "d836870543677303f1cb6f9649e955c772e9f15311c2926a2468c9a10eb214d9",

third_party/modules/libxev/20252401.0-31eed4e/MODULE.bazel

@@ -0,0 +1,7 @@
+module(
+    name = "libxev",
+    version = "20252401.0-31eed4e",
+    compatibility_level = 1,
+)
+
+bazel_dep(name = "rules_zig", version = "20240904.0-010da15")

third_party/modules/libxev/20252401.0-31eed4e/overlay/BUILD.bazel

@@ -0,0 +1,13 @@
+load("@rules_zig//zig:defs.bzl", "zig_library")
+
+zig_library(
+    name = "xev",
+    srcs = glob([
+        "src/*.zig",
+        "src/backend/*.zig",
+        "src/linux/*.zig",
+        "src/watcher/*.zig",
+    ]),
+    main = "main2.zig",
+    visibility = ["//visibility:public"],
+)

third_party/modules/libxev/20252401.0-31eed4e/overlay/MODULE.bazel

@@ -0,0 +1,7 @@
+module(
+    name = "libxev",
+    version = "20252401.0-31eed4e",
+    compatibility_level = 1,
+)
+
+bazel_dep(name = "rules_zig", version = "20240904.0-010da15")

third_party/modules/libxev/20252401.0-31eed4e/overlay/main2.zig

@@ -0,0 +1,22 @@
+const builtin = @import("builtin");
+const root = @import("root");
+
+const main = @import("src/main.zig");
+
+pub const ThreadPool = main.ThreadPool;
+pub const stream = main.stream;
+
+pub const Options = struct {
+    linux_backend: main.Backend = .epoll,
+};
+
+pub const options: Options = if (@hasDecl(root, "xev_options")) root.xev_options else .{};
+
+const default: main.Backend = switch (builtin.os.tag) {
+    .ios, .macos => .kqueue,
+    .linux => options.linux_backend,
+    .wasi => .wasi_poll,
+    .windows => .iocp,
+    else => @compileError("Unsupported OS"),
+};
+pub usingnamespace default.Api();

third_party/modules/libxev/20252401.0-31eed4e/patches/128.patch

@@ -0,0 +1,359 @@
+From 7b345e8d423f6cb1907f0dcba1d3c2f82e4c6b4d Mon Sep 17 00:00:00 2001
+From: Steeve Morin <steeve@zml.ai>
+Date: Tue, 19 Nov 2024 16:14:14 +0100
+Subject: [PATCH 1/5] backend/epoll: implement eventfd wakeup notification
+
+Tries to mimic what happens in backend/kqueue.
+
+Closes #4
+---
+ src/backend/epoll.zig | 42 ++++++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 42 insertions(+)
+
+diff --git a/src/backend/epoll.zig b/src/backend/epoll.zig
+index ae4ec7d..f44d326 100644
+--- a/src/backend/epoll.zig
++++ b/src/backend/epoll.zig
+@@ -21,6 +21,12 @@ pub const Loop = struct {
+ 
+     fd: posix.fd_t,
+ 
++    /// The eventfd that this epoll queue always has a filter for. Writing
++    /// an empty message to this eventfd can be used to wake up the loop
++    /// at any time. Waking up the loop via this eventfd won't trigger any
++    /// particular completion, it just forces tick to cycle.
++    eventfd: xev.Async,
++
+     /// The number of active completions. This DOES NOT include completions that
+     /// are queued in the submissions queue.
+     active: usize = 0,
+@@ -56,8 +62,12 @@ pub const Loop = struct {
+     } = .{},
+ 
+     pub fn init(options: xev.Options) !Loop {
++        var eventfd = try xev.Async.init();
++        errdefer eventfd.deinit();
++
+         var res: Loop = .{
+             .fd = try posix.epoll_create1(std.os.linux.EPOLL.CLOEXEC),
++            .eventfd = eventfd,
+             .thread_pool = options.thread_pool,
+             .thread_pool_completions = undefined,
+             .cached_now = undefined,
+@@ -68,6 +78,7 @@ pub const Loop = struct {
+ 
+     pub fn deinit(self: *Loop) void {
+         posix.close(self.fd);
++        self.eventfd.deinit();
+     }
+ 
+     /// Run the event loop. See RunMode documentation for details on modes.
+@@ -262,9 +273,26 @@ pub const Loop = struct {
+         // Initialize
+         if (!self.flags.init) {
+             self.flags.init = true;
++
+             if (self.thread_pool != null) {
+                 self.thread_pool_completions.init();
+             }
++
++            var ev: linux.epoll_event = .{
++                .events = linux.EPOLL.IN | linux.EPOLL.RDHUP,
++                .data = .{ .ptr = 0 },
++            };
++            posix.epoll_ctl(
++                self.fd,
++                linux.EPOLL.CTL_ADD,
++                self.eventfd.fd,
++                &ev,
++            ) catch |err| {
++                // We reset initialization because we can't do anything
++                // safely unless we get this mach port registered!
++                self.flags.init = false;
++                return err;
++            };
+         }
+ 
+         // Submit all the submissions. We copy the submission queue so that
+@@ -369,6 +397,10 @@ pub const Loop = struct {
+ 
+             // Process all our events and invoke their completion handlers
+             for (events[0..n]) |ev| {
++                // Zero data values are internal events that we do nothing
++                // on such as the eventfd wakeup.
++                if (ev.data.ptr == 0) continue;
++
+                 const c: *Completion = @ptrFromInt(@as(usize, @intCast(ev.data.ptr)));
+ 
+                 // We get the fd and mark this as in progress we can properly
+@@ -415,6 +447,7 @@ pub const Loop = struct {
+         const pool = self.thread_pool orelse return error.ThreadPoolRequired;
+ 
+         // Setup our completion state so that thread_perform can do stuff
++        c.task_loop = self;
+         c.task_completions = &self.thread_pool_completions;
+         c.task = .{ .callback = Loop.thread_perform };
+ 
+@@ -436,6 +469,14 @@ pub const Loop = struct {
+ 
+         // Add to our completion queue
+         c.task_completions.push(c);
++
++        // Wake up our main loop
++        c.task_loop.wakeup() catch {};
++    }
++
++    /// Sends an empty message to this loop's eventfd so that it wakes up.
++    fn wakeup(self: *Loop) !void {
++        try self.eventfd.notify();
+     }
+ 
+     fn start(self: *Loop, completion: *Completion) void {
+@@ -800,6 +841,7 @@ pub const Completion = struct {
+     /// reliable way to get access to the loop and shouldn't be used
+     /// except internally.
+     task: ThreadPool.Task = undefined,
++    task_loop: *Loop = undefined,
+     task_completions: *Loop.TaskCompletionQueue = undefined,
+     task_result: Result = undefined,
+ 
+-- 
+2.39.5 (Apple Git-154)
+
+From 40dc25fa922fe436418f9c01acd9b76a74593ddb Mon Sep 17 00:00:00 2001
+From: Corentin Godeau <corentin@zml.ai>
+Date: Tue, 14 Jan 2025 14:43:54 +0000
+Subject: [PATCH 2/5] backend/epoll: read the wakeup eventfd to avoid being
+ awaken again
+
+---
+ src/backend/epoll.zig | 11 +++++++----
+ 1 file changed, 7 insertions(+), 4 deletions(-)
+
+diff --git a/src/backend/epoll.zig b/src/backend/epoll.zig
+index f44d326..f84c687 100644
+--- a/src/backend/epoll.zig
++++ b/src/backend/epoll.zig
+@@ -280,7 +280,7 @@ pub const Loop = struct {
+ 
+             var ev: linux.epoll_event = .{
+                 .events = linux.EPOLL.IN | linux.EPOLL.RDHUP,
+-                .data = .{ .ptr = 0 },
++                .data = .{ .fd = self.eventfd.fd },
+             };
+             posix.epoll_ctl(
+                 self.fd,
+@@ -397,9 +397,12 @@ pub const Loop = struct {
+ 
+             // Process all our events and invoke their completion handlers
+             for (events[0..n]) |ev| {
+-                // Zero data values are internal events that we do nothing
+-                // on such as the eventfd wakeup.
+-                if (ev.data.ptr == 0) continue;
++                // Handle wakeup eventfd
++                if (ev.data.fd == self.eventfd.fd) {
++                    var buffer: u64 = undefined;
++                    _ = posix.read(self.eventfd.fd, std.mem.asBytes(&buffer)) catch {};
++                    continue;
++                }
+ 
+                 const c: *Completion = @ptrFromInt(@as(usize, @intCast(ev.data.ptr)));
+ 
+-- 
+2.39.5 (Apple Git-154)
+
+From c082ed1270a59d4276d7ac6752833b6730fa73d5 Mon Sep 17 00:00:00 2001
+From: Steeve Morin <steeve@zml.ai>
+Date: Fri, 17 Jan 2025 20:47:42 +0000
+Subject: [PATCH 3/5] epoll: use infinite timeout for epoll_wait
+
+Since eventfd is now implemented.
+---
+ src/backend/epoll.zig | 4 +---
+ 1 file changed, 1 insertion(+), 3 deletions(-)
+
+diff --git a/src/backend/epoll.zig b/src/backend/epoll.zig
+index f84c687..e3eee20 100644
+--- a/src/backend/epoll.zig
++++ b/src/backend/epoll.zig
+@@ -375,9 +375,7 @@ pub const Loop = struct {
+             const timeout: i32 = if (wait_rem == 0) 0 else timeout: {
+                 // If we have a timer, we want to set the timeout to our next
+                 // timer value. If we have no timer, we wait forever.
+-                // TODO: do not wait 100ms here, use an eventfd for our
+-                // thread pool to wake us up.
+-                const t = self.timers.peek() orelse break :timeout 100;
++                const t = self.timers.peek() orelse break :timeout -1;
+ 
+                 // Determine the time in milliseconds.
+                 const ms_now = @as(u64, @intCast(self.cached_now.tv_sec)) * std.time.ms_per_s +
+-- 
+2.39.5 (Apple Git-154)
+
+From e8f23275bf736bcc39cb0c9e4617f6e1338c5880 Mon Sep 17 00:00:00 2001
+From: Steeve Morin <steeve@zml.ai>
+Date: Fri, 17 Jan 2025 20:48:27 +0000
+Subject: [PATCH 4/5] epoll,kqueue: dispatch close in threadpool
+
+Close might block, so dispatch it inside a threadpool.
+---
+ src/backend/epoll.zig  | 15 +++++++++++++--
+ src/backend/kqueue.zig |  6 +++++-
+ src/watcher/stream.zig | 16 ++++++++++++++++
+ 3 files changed, 34 insertions(+), 3 deletions(-)
+
+diff --git a/src/backend/epoll.zig b/src/backend/epoll.zig
+index e3eee20..0f4a2ac 100644
+--- a/src/backend/epoll.zig
++++ b/src/backend/epoll.zig
+@@ -700,6 +700,13 @@ pub const Loop = struct {
+             },
+ 
+             .close => |v| res: {
++                if (completion.flags.threadpool) {
++                    if (self.thread_schedule(completion)) |_|
++                        return
++                    else |err|
++                        break :res .{ .close = err };
++                }
++
+                 posix.close(v.fd);
+                 break :res .{ .close = {} };
+             },
+@@ -909,7 +916,6 @@ pub const Completion = struct {
+             // This should never happen because we always do these synchronously
+             // or in another location.
+             .cancel,
+-            .close,
+             .noop,
+             .shutdown,
+             .timer,
+@@ -1015,6 +1021,11 @@ pub const Completion = struct {
+                         err,
+                 };
+             },
++
++            .close => |*op| res: {
++                posix.close(op.fd);
++                break :res .{ .close = {} };
++            },
+         };
+     }
+ 
+@@ -1277,7 +1288,7 @@ pub const AcceptError = posix.EpollCtlError || error{
+     Unknown,
+ };
+ 
+-pub const CloseError = posix.EpollCtlError || error{
++pub const CloseError = posix.EpollCtlError || ThreadPoolError || error{
+     Unknown,
+ };
+ 
+diff --git a/src/backend/kqueue.zig b/src/backend/kqueue.zig
+index 456f64f..9914309 100644
+--- a/src/backend/kqueue.zig
++++ b/src/backend/kqueue.zig
+@@ -1102,7 +1102,6 @@ pub const Completion = struct {
+     fn perform(self: *Completion, ev_: ?*const Kevent) Result {
+         return switch (self.op) {
+             .cancel,
+-            .close,
+             .noop,
+             .timer,
+             .shutdown,
+@@ -1232,6 +1231,11 @@ pub const Completion = struct {
+ 
+                 break :res .{ .proc = 0 };
+             },
++
++            .close => |*op| res: {
++                posix.close(op.fd);
++                break :res .{ .close = {} };
++            },
+         };
+     }
+ 
+diff --git a/src/watcher/stream.zig b/src/watcher/stream.zig
+index 7f5df6f..bc95282 100644
+--- a/src/watcher/stream.zig
++++ b/src/watcher/stream.zig
+@@ -80,6 +80,22 @@ pub fn Closeable(comptime xev: type, comptime T: type, comptime options: Options
+                 }).callback,
+             };
+ 
++            // If we're dup-ing, then we ask the backend to manage the fd.
++            switch (xev.backend) {
++                .io_uring,
++                .wasi_poll,
++                .iocp,
++                => {},
++
++                .epoll => {
++                    c.flags.threadpool = true;
++                },
++
++                .kqueue => {
++                    c.flags.threadpool = true;
++                },
++            }
++
+             loop.add(c);
+         }
+     };
+-- 
+2.39.5 (Apple Git-154)
+
+From 378a3968b8820aef5a6ab64d1893d022b1b6d70c Mon Sep 17 00:00:00 2001
+From: Steeve Morin <steeve@zml.ai>
+Date: Fri, 17 Jan 2025 20:59:18 +0000
+Subject: [PATCH 5/5] epoll: don't count immediate actions
+
+If an immediate action is dispatched, the loop might block
+on epoll_wait even though only one action was requested.
+---
+ src/backend/epoll.zig | 15 ++++++++++++++-
+ 1 file changed, 14 insertions(+), 1 deletion(-)
+
+diff --git a/src/backend/epoll.zig b/src/backend/epoll.zig
+index 0f4a2ac..fb7e59e 100644
+--- a/src/backend/epoll.zig
++++ b/src/backend/epoll.zig
+@@ -297,6 +297,7 @@ pub const Loop = struct {
+ 
+         // Submit all the submissions. We copy the submission queue so that
+         // any resubmits don't cause an infinite loop.
++        var wait_rem: usize = @intCast(wait);
+         var queued = self.submissions;
+         self.submissions = .{};
+         while (queued.pop()) |c| {
+@@ -304,6 +305,19 @@ pub const Loop = struct {
+             // This usually means that we switched them to be deleted or
+             // something.
+             if (c.flags.state != .adding) continue;
++
++            // These operations happen synchronously. Ensure they are
++            // decremented from wait_rem.
++            switch (c.op) {
++                .cancel,
++                // should noop be counted?
++                // .noop,
++                .shutdown,
++                .timer,
++                => wait_rem -|= 1,
++                else => {},
++            }
++
+             self.start(c);
+         }
+ 
+@@ -322,7 +336,6 @@ pub const Loop = struct {
+ 
+         // Wait and process events. We only do this if we have any active.
+         var events: [1024]linux.epoll_event = undefined;
+-        var wait_rem: usize = @intCast(wait);
+         while (self.active > 0 and (wait == 0 or wait_rem > 0)) {
+             self.update_now();
+             const now_timer: Operation.Timer = .{ .next = self.cached_now };
+-- 
+2.39.5 (Apple Git-154)
+

third_party/modules/libxev/20252401.0-31eed4e/patches/141.patch

@@ -0,0 +1,35 @@
+From 283a911561385e0cc9278dfd350bdc5c5132c9c4 Mon Sep 17 00:00:00 2001
+From: Steeve Morin <steeve@zml.ai>
+Date: Wed, 5 Feb 2025 11:17:01 +0100
+Subject: [PATCH] backend/kqueue: fix empty udata crash
+
+On certain occasions, internal kqueue events are dispatched with an empty udata field.
+This causes a crash when trying to access the udata field in the event handler.
+
+This patch adds a check to ensure that the udata field is not empty before accessing it
+just like in the other events consumer.
+---
+ src/backend/kqueue.zig | 6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+diff --git a/src/backend/kqueue.zig b/src/backend/kqueue.zig
+index 456f64f..7d919ce 100644
+--- a/src/backend/kqueue.zig
++++ b/src/backend/kqueue.zig
+@@ -206,11 +206,15 @@ pub const Loop = struct {
+             // event list to zero length) because it was leading to
+             // memory corruption we need to investigate.
+             for (events[0..completed]) |ev| {
+-                const c: *Completion = @ptrFromInt(@as(usize, @intCast(ev.udata)));
++                // Zero udata values are internal events that we do nothing
++                // on such as the mach port wakeup.
++                if (ev.udata == 0) continue;
+ 
+                 // We handle deletions separately.
+                 if (ev.flags & posix.system.EV_DELETE != 0) continue;
+ 
++                const c: *Completion = @ptrFromInt(@as(usize, @intCast(ev.udata)));
++
+                 // If EV_ERROR is set, then submission failed for this
+                 // completion. We get the syscall errorcode from data and
+                 // store it.

third_party/modules/libxev/20252401.0-31eed4e/source.json

@@ -0,0 +1,15 @@
+{
+    "strip_prefix": "libxev-31eed4e337fed7b0149319e5cdbb62b848c24fbd",
+    "url": "https://github.com/zml/libxev/archive/31eed4e337fed7b0149319e5cdbb62b848c24fbd.tar.gz",
+    "integrity": "sha256-VHP90NTytIZ8UZsYRKOOxN490/I6yv6ec40sP8y5MJ8=",
+    "overlay": {
+        "MODULE.bazel": "",
+        "BUILD.bazel": "",
+        "main2.zig": ""
+    },
+    "patches": {
+        "128.patch": "",
+        "141.patch": ""
+    },
+    "patch_strip": 1
+}