FreeChainXenon/newlib-cygwin
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Cygwin: console: Fixes an issue that tmux can not run on the console.

Browse source 
After the commit c77a5689f7, tmux can not run on the console.
This patch replaces the countermeasure for the race issue between
console setup and close with another mechanism using a mutex.

Fixes: c77a5689f7 ("Cygwin: console: Do not unmap shared console memory belonging to ctty.")
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
This commit is contained in:
Takashi Yano 2024-07-06 13:50:51 +09:00
parent f7a77d0146
commit baf2764dca
1 changed files with 14 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

15
winsup/cygwin/fhandler/console.cc
View file

@ -48,6 +48,9 @@ details. */
con.b.srWindow.Top + con.scroll_region.Bottom) con.b.srWindow.Top + con.scroll_region.Bottom)
#define con_is_legacy (shared_console_info[unit] && con.is_legacy) #define con_is_legacy (shared_console_info[unit] && con.is_legacy)
static HANDLE NO_COPY shared_info_mutex;
static int NO_COPY shared_info_state;
#define CONS_THREAD_SYNC "cygcons.thread_sync" #define CONS_THREAD_SYNC "cygcons.thread_sync"
static bool NO_COPY master_thread_started = false; static bool NO_COPY master_thread_started = false;
@ -665,6 +668,12 @@ fhandler_console::set_unit ()
else if (myself->ctty != CTTY_UNINITIALIZED) else if (myself->ctty != CTTY_UNINITIALIZED)
unit = device::minor (myself->ctty); unit = device::minor (myself->ctty);
if (!shared_info_mutex)
shared_info_mutex = CreateMutex (&sec_none_nih, FALSE, NULL);
WaitForSingleObject (shared_info_mutex, INFINITE);
shared_info_state++;
if (shared_console_info[unit]) if (shared_console_info[unit])
; /* Do nothing */ ; /* Do nothing */
else if (generic_console else if (generic_console
@ -698,6 +707,8 @@ fhandler_console::set_unit ()
} }
} }
} }
ReleaseMutex (shared_info_mutex);
if (shared_console_info[unit]) if (shared_console_info[unit])
{ {
devset = (fh_devices) shared_console_info[unit]->tty_min_state.getntty (); devset = (fh_devices) shared_console_info[unit]->tty_min_state.getntty ();
@ -1963,11 +1974,13 @@ fhandler_console::close ()
CloseHandle (output_mutex); CloseHandle (output_mutex);
output_mutex = NULL; output_mutex = NULL;
if (shared_console_info[unit] && myself->ctty != tc ()->ntty) WaitForSingleObject (shared_info_mutex, INFINITE);
if (--shared_info_state == 0 && shared_console_info[unit])
{ {
UnmapViewOfFile ((void *) shared_console_info[unit]); UnmapViewOfFile ((void *) shared_console_info[unit]);
shared_console_info[unit] = NULL; shared_console_info[unit] = NULL;
} }
ReleaseMutex (shared_info_mutex);
return 0; return 0;
} }