From 673ddd9739d2a295b83641ad6d3357b35a194981 Mon Sep 17 00:00:00 2001
From: Kim Woelders <kw@thrane.eu>
Date: Wed, 17 Oct 2018 13:50:47 +0200
Subject: [PATCH] Fix RFC2217 server death

We now properly kick the connected clients hanging in reads (cu) instead
of locking up.
---
 ttynvt.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/ttynvt.c b/ttynvt.c
index eddd15d..b36242b 100644
--- a/ttynvt.c
+++ b/ttynvt.c
@@ -56,7 +56,8 @@ static struct ttynvt_param {
 typedef struct {
     pthread_mutex_t tty_lock;
     pthread_mutex_t poll_lock;
-    pthread_t       thread_id;
+    pthread_t       ptid_poll;
+    pthread_t       ptid_read;
 
     struct fuse_pollhandle *ph;
 
@@ -186,8 +187,8 @@ static void ttynvt_release(fuse_req_t req, struct fuse_file_info *info)
     close(tty->fds[FD_MASTER].fd);
     close(tty->fds[FD_SLAVE].fd);
 
-    pthread_cancel(tty->thread_id);
-    pthread_join(tty->thread_id, NULL);
+    pthread_cancel(tty->ptid_poll);
+    pthread_join(tty->ptid_poll, NULL);
     pthread_mutex_destroy(&tty->tty_lock);
     pthread_mutex_destroy(&tty->poll_lock);
 
@@ -302,6 +303,8 @@ static void    *_read_net(void *arg)
     }
 
     DBG2("%s: done\n", __func__);
+    if (tty->ptid_read)
+        pthread_kill(tty->ptid_read, SIGUSR2);
 
     tty->error = 1;
     _notify(tty);
@@ -508,7 +511,7 @@ static void ttynvt_open(fuse_req_t req, struct fuse_file_info *info)
     }
     if ((res = pthread_mutex_init(&tty->tty_lock, NULL) < 0) ||
         (res = pthread_mutex_init(&tty->poll_lock, NULL) < 0) ||
-        (res = pthread_create(&tty->thread_id, NULL, &_read_net, tty)))
+        (res = pthread_create(&tty->ptid_poll, NULL, &_read_net, tty)))
     {
         errno = res;
         goto open_err;
@@ -569,9 +572,11 @@ ttynvt_read(fuse_req_t req, size_t size, off_t off,
     if (size > TMP_BUF_SIZE)
         size = TMP_BUF_SIZE;
 
-    fuse_req_interrupt_func(req, ttynvt_interrupted, (void *)pthread_self());
+    tty->ptid_read = pthread_self();
+    fuse_req_interrupt_func(req, ttynvt_interrupted, (void *)tty->ptid_read);
     res = _is_interrupted ? -2 : read(tty->fds[FD_SLAVE].fd, buf, size);
     _is_interrupted = 0;
+    tty->ptid_read = 0;
     tty->n_fds = 3;             /* Enable polling of Slave */
     fuse_req_interrupt_func(req, NULL, NULL);
     if (res < 0)