From: Takashi Yano <takashi.yano@nifty.ne.jp>
To: cygwin-patches@cygwin.com
Subject: [PATCH v3 1/2] Cygwin: console: Make read() thread-safe.
Date: Thu, 28 Jan 2021 23:11:32 +0900 [thread overview]
Message-ID: <20210128141133.734-2-takashi.yano@nifty.ne.jp> (raw)
In-Reply-To: <20210128141133.734-1-takashi.yano@nifty.ne.jp>
- Currently read() is somehow not thread-safe. This patch fixes
the issue.
---
winsup/cygwin/fhandler.h | 10 ++++++++++
winsup/cygwin/fhandler_console.cc | 11 ++++++-----
winsup/cygwin/fhandler_termios.cc | 2 ++
3 files changed, 18 insertions(+), 5 deletions(-)
diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index a4c1a3816..2fad7d33c 100644
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -1905,6 +1905,8 @@ class fhandler_termios: public fhandler_base
tty_min *_tc;
tty *get_ttyp () {return (tty *) tc ();}
int eat_readahead (int n);
+ virtual void acquire_input_mutex_if_necessary (DWORD ms) {};
+ virtual void release_input_mutex_if_necessary (void) {};
public:
tty_min*& tc () {return _tc;}
@@ -2212,6 +2214,14 @@ private:
void __release_input_mutex (const char *fn, int ln);
DWORD __acquire_output_mutex (const char *fn, int ln, DWORD ms);
void __release_output_mutex (const char *fn, int ln);
+ void acquire_input_mutex_if_necessary (DWORD ms)
+ {
+ acquire_input_mutex (ms);
+ }
+ void release_input_mutex_if_necessary (void)
+ {
+ release_input_mutex ();
+ }
char *&rabuf ();
size_t &ralen ();
diff --git a/winsup/cygwin/fhandler_console.cc b/winsup/cygwin/fhandler_console.cc
index 02d0ac052..0b404411e 100644
--- a/winsup/cygwin/fhandler_console.cc
+++ b/winsup/cygwin/fhandler_console.cc
@@ -571,31 +571,34 @@ wait_retry:
#define buf ((char *) pv)
int ret;
- acquire_attach_mutex (INFINITE);
acquire_input_mutex (INFINITE);
+ acquire_attach_mutex (INFINITE);
ret = process_input_message ();
- release_input_mutex ();
release_attach_mutex ();
switch (ret)
{
case input_error:
+ release_input_mutex ();
goto err;
case input_processing:
+ release_input_mutex ();
continue;
case input_ok: /* input ready */
break;
case input_signalled: /* signalled */
+ release_input_mutex ();
goto sig_exit;
case input_winch:
+ release_input_mutex ();
continue;
default:
/* Should not come here */
+ release_input_mutex ();
goto err;
}
}
/* Check console read-ahead buffer filled from terminal requests */
- acquire_input_mutex (INFINITE);
while (con.cons_rapoi && *con.cons_rapoi && buflen)
{
buf[copied_chars++] = *con.cons_rapoi++;
@@ -984,9 +987,7 @@ fhandler_console::process_input_message (void)
if (toadd)
{
ssize_t ret;
- release_input_mutex ();
line_edit_status res = line_edit (toadd, nread, *ti, &ret);
- acquire_input_mutex (INFINITE);
if (res == line_edit_signalled)
{
stat = input_signalled;
diff --git a/winsup/cygwin/fhandler_termios.cc b/winsup/cygwin/fhandler_termios.cc
index 36bc6255f..9fbace95c 100644
--- a/winsup/cygwin/fhandler_termios.cc
+++ b/winsup/cygwin/fhandler_termios.cc
@@ -332,7 +332,9 @@ fhandler_termios::line_edit (const char *rptr, size_t nread, termios& ti,
termios_printf ("got interrupt %d, sending signal %d", c, sig);
eat_readahead (-1);
+ release_input_mutex_if_necessary ();
tc ()->kill_pgrp (sig);
+ acquire_input_mutex_if_necessary (INFINITE);
ti.c_lflag &= ~FLUSHO;
sawsig = true;
goto restart_output;
--
2.30.0
next prev parent reply other threads:[~2021-01-28 14:12 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-28 14:11 [PATCH v3 0/2] Make terminal " Takashi Yano
2021-01-28 14:11 ` Takashi Yano [this message]
2021-01-28 14:11 ` [PATCH v3 2/2] Cygwin: pty: Make slave " Takashi Yano
2021-02-01 10:01 ` [PATCH v3 0/2] Make terminal " Corinna Vinschen
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