From 419aea54cb30b394191778fcc70effaf5181bf33 Mon Sep 17 00:00:00 2001
From: Loris Cro <kappaloris@gmail.com>
Date: Sat, 20 Jun 2020 00:35:08 +0200
Subject: [PATCH] sendto

Signed-off-by: Loris Cro <kappaloris@gmail.com>
---
 lib/std/event/loop.zig | 21 +++++++++++++++++++++
 lib/std/net.zig        | 12 ++++++++++--
 lib/std/os.zig         |  8 +-------
 3 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/lib/std/event/loop.zig b/lib/std/event/loop.zig
index ae2d2f149..3a79d36a1 100644
--- a/lib/std/event/loop.zig
+++ b/lib/std/event/loop.zig
@@ -1088,6 +1088,27 @@ pub const Loop = struct {
         }
     }
 
+    pub fn sendto(
+        self: *Loop,
+        /// The file descriptor of the sending socket.
+        sockfd: os.fd_t,
+        /// Message to send.
+        buf: []const u8,
+        flags: u32,
+        dest_addr: ?*const os.sockaddr,
+        addrlen: os.socklen_t,
+    ) os.SendError!usize {
+        while (true) {
+            return os.sendto(sockfd, buf, flags, dest_addr, addrlen) catch |err| switch (err) {
+                error.WouldBlock => {
+                    self.waitUntilFdWritable(sockfd);
+                    continue;
+                },
+                else => return err,
+            };
+        }
+    }
+
     /// Performs an async `os.faccessatZ` using a separate thread.
     /// `fd` must block and not return EAGAIN.
     pub fn faccessatZ(
diff --git a/lib/std/net.zig b/lib/std/net.zig
index 928ebbbce..8fe19f955 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1435,7 +1435,11 @@ fn resMSendRc(
                 if (answers[i].len == 0) {
                     var j: usize = 0;
                     while (j < ns.len) : (j += 1) {
-                        _ = os.sendto(fd, queries[i], os.MSG_NOSIGNAL, &ns[j].any, sl) catch undefined;
+                        if (std.io.is_async) {
+                            _ = std.event.Loop.instance.?.sendto(fd, queries[i], os.MSG_NOSIGNAL, &ns[j].any, sl) catch undefined;
+                        } else {
+                            _ = os.sendto(fd, queries[i], os.MSG_NOSIGNAL, &ns[j].any, sl) catch undefined;
+                        }
                     }
                 }
             }
@@ -1476,7 +1480,11 @@ fn resMSendRc(
                 0, 3 => {},
                 2 => if (servfail_retry != 0) {
                     servfail_retry -= 1;
-                    _ = os.sendto(fd, queries[i], os.MSG_NOSIGNAL, &ns[j].any, sl) catch undefined;
+                    if (std.io.is_async) {
+                        _ = std.event.Loop.instance.?.sendto(fd, queries[i], os.MSG_NOSIGNAL, &ns[j].any, sl) catch undefined;
+                    } else {
+                        _ = os.sendto(fd, queries[i], os.MSG_NOSIGNAL, &ns[j].any, sl) catch undefined;
+                    }
                 },
                 else => continue,
             }
diff --git a/lib/std/os.zig b/lib/std/os.zig
index 1138013e8..2f354e33d 100644
--- a/lib/std/os.zig
+++ b/lib/std/os.zig
@@ -4571,14 +4571,8 @@ pub fn sendto(
         const rc = system.sendto(sockfd, buf.ptr, buf.len, flags, dest_addr, addrlen);
         switch (errno(rc)) {
             0 => return @intCast(usize, rc),
-
             EACCES => return error.AccessDenied,
-            EAGAIN => if (std.event.Loop.instance) |loop| {
-                loop.waitUntilFdWritable(sockfd);
-                continue;
-            } else {
-                return error.WouldBlock;
-            },
+            EAGAIN => return error.WouldBlock,
             EALREADY => return error.FastOpenAlreadyInProgress,
             EBADF => unreachable, // always a race condition
             ECONNRESET => return error.ConnectionResetByPeer,