From 491b27ebc36a48e39005748c30a0dcda61e3f904 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Wed, 15 Apr 2026 02:38:12 +0300
Subject: [PATCH] veb: fix long process started from app hogging CPU (fixes
 #26742)

---
 vlib/picoev/picoev.v                        |  7 +++++++
 vlib/picoev/picoev_interrupt_test_linux.c.v | 22 +++++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 vlib/picoev/picoev_interrupt_test_linux.c.v

diff --git a/vlib/picoev/picoev.v b/vlib/picoev/picoev.v
index 6ace906d8..eb15913a4 100644
--- a/vlib/picoev/picoev.v
+++ b/vlib/picoev/picoev.v
@@ -131,6 +131,13 @@ pub fn (mut pv Picoev) delete(fd int) int {
 fn (mut pv Picoev) loop_once(max_wait_in_sec int) int {
 	pv.loop.now = get_time()
 	if pv.poll_once(max_wait_in_sec) != 0 {
+		$if !windows {
+			if C.errno == net.error_eintr {
+				// Signal-driven wakeups are transient. The caller should keep serving,
+				// instead of spinning on a logged "error" until the signal source stops.
+				return 0
+			}
+		}
 		elog('Error during poll_once')
 		return -1
 	}
diff --git a/vlib/picoev/picoev_interrupt_test_linux.c.v b/vlib/picoev/picoev_interrupt_test_linux.c.v
new file mode 100644
index 000000000..d5388e754
--- /dev/null
+++ b/vlib/picoev/picoev_interrupt_test_linux.c.v
@@ -0,0 +1,22 @@
+module picoev
+
+import os
+
+#include <unistd.h>
+
+fn C.alarm(seconds u32) u32
+
+fn ignore_test_signal(_ os.Signal) {}
+
+fn test_loop_once_ignores_eintr() {
+	mut pv := &Picoev{}
+	pv.loop = create_epoll_loop(0) or { panic(err) }
+	pv.init()
+	prev_handler := os.signal_opt(.alrm, ignore_test_signal) or { panic(err) }
+	defer {
+		C.alarm(0)
+		os.signal_opt(.alrm, prev_handler) or { panic(err) }
+	}
+	C.alarm(1)
+	assert pv.loop_once(2) == 0
+}
-- 
2.39.5