From 2bd5e698ae6fd85d6671cd9cad94abaa0cd5d92d Mon Sep 17 00:00:00 2001
From: Leah Neukirchen <leah@vuxu.org>
Date: Thu, 3 Feb 2022 22:10:26 +0100
Subject: detect closed pipes in logger_loop where POLLIN was set

---
 rvnit.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/rvnit.c b/rvnit.c
index c7b9038..8c7b36b 100644
--- a/rvnit.c
+++ b/rvnit.c
@@ -452,6 +452,7 @@ logger_loop(void* ignored)
 
 			if ((fds[j].revents & (POLLHUP | POLLERR)) &&
 			    !(fds[j].revents & POLLIN)) {
+closed_pipe:
 				/* write end was closed, close whole pipe */
 				pthread_mutex_lock(&services_lock);
 				for (int i = 0; i < MAX_SV; i++) {
@@ -482,6 +483,12 @@ logger_loop(void* ignored)
 				continue;
 			}
 
+			if (rd == 0) {
+				// some OS set POLLIN|POLLHUP on closed pipes
+				// https://www.greenend.org.uk/rjk/tech/poll.html
+				goto closed_pipe;
+			}
+
 			if (rd < (int)sizeof buf && buf[rd - 1] != '\n') {
 				// sometimes processes use multiple write calls
 				// for one line, give them 25msec to do try to
-- 
cgit 1.4.1