Commit 55f437b92bb394f7df558bb3209f057f9f46274f | zig

author	SuperAuguste <19855629+SuperAuguste@users.noreply.github.com> 2024-02-24 15:44:57-05:00
committer	Andrew Kelley <andrew@ziglang.org> 2024-02-25 01:41:56-08:00
log	55f437b92bb394f7df558bb3209f057f9f46274f
tree	48df981452556786884c3b4d53ef767b81da8aff
parent	6c2eb0f131588be111652a755a4492ff72d16440

Add pollTimeout for non-blocking/timeout-having polls

1 files changed, 22 insertions(+), 6 deletions(-)

lib
- std
  - io.zig

lib/std/io.zig+22-6

 @@ -512,9 +512,17 @@ pub fn Poller(comptime StreamEnum: type) type {
         pub fn poll(self: *Self) !bool {
             if (builtin.os.tag == .windows) {
-                return pollWindows(self);
+                return pollWindows(self, null);
             } else {
-                return pollPosix(self);
+                return pollPosix(self, null);
+            }
+        }
+        pub fn pollTimeout(self: *Self, nanoseconds: u64) !bool {
+            if (builtin.os.tag == .windows) {
+                return pollWindows(self, nanoseconds);
+            } else {
+                return pollPosix(self, nanoseconds);
             }
         }
 @@ -522,7 +530,7 @@ pub fn Poller(comptime StreamEnum: type) type {
             return &self.fifos[@intFromEnum(which)];
         }
-        fn pollWindows(self: *Self) !bool {
+        fn pollWindows(self: *Self, nanoseconds: ?u64) !bool {
             const bump_amt = 512;
             if (!self.windows.first_read_done) {
 @@ -553,10 +561,15 @@ pub fn Poller(comptime StreamEnum: type) type {
                     self.windows.active.count,
                     &self.windows.active.handles_buf,
                     0,
-                    os.windows.INFINITE,
+                    if (nanoseconds) |ns|
+                        @min(std.math.cast(u32, ns / std.time.ns_per_ms) orelse (os.windows.INFINITE - 1), os.windows.INFINITE - 1)
+                    else
+                        os.windows.INFINITE,
                 );
                 if (status == os.windows.WAIT_FAILED)
                     return os.windows.unexpectedError(os.windows.kernel32.GetLastError());
+                if (status == os.windows.WAIT_TIMEOUT)
+                    return true;
                 if (status < os.windows.WAIT_OBJECT_0 or status > os.windows.WAIT_OBJECT_0 + enum_fields.len - 1)
                     unreachable;
 @@ -594,7 +607,7 @@ pub fn Poller(comptime StreamEnum: type) type {
             }
         }
-        fn pollPosix(self: *Self) !bool {
+        fn pollPosix(self: *Self, nanoseconds: ?u64) !bool {
             // We ask for ensureUnusedCapacity with this much extra space. This
             // has more of an effect on small reads because once the reads
             // start to get larger the amount of space an ArrayList will
 @@ -603,7 +616,10 @@ pub fn Poller(comptime StreamEnum: type) type {
             const err_mask = os.POLL.ERR | os.POLL.NVAL | os.POLL.HUP;
-            const events_len = try os.poll(&self.poll_fds, std.math.maxInt(i32));
+            const events_len = try os.poll(&self.poll_fds, if (nanoseconds) |ns|
+                std.math.cast(i32, ns / std.time.ns_per_ms) orelse std.math.maxInt(i32)
+            else
+                -1);
             if (events_len == 0) {
                 for (self.poll_fds) |poll_fd| {
                     if (poll_fd.fd != -1) return true;