From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2155) id 54E913860C32; Tue, 6 Apr 2021 10:21:02 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 54E913860C32 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Corinna Vinschen To: cygwin-cvs@sourceware.org Subject: [newlib-cygwin] Cygwin: pty: Use atexit() instead of hooking exit() for GDB. X-Act-Checkin: newlib-cygwin X-Git-Author: Takashi Yano X-Git-Refname: refs/heads/master X-Git-Oldrev: ba2fbfec95b03ccd01c4d3f5a5179e7cc5f95e19 X-Git-Newrev: 8bb5161fe3bdccbe94482715b71dd26d6d3e79e3 Message-Id: <20210406102102.54E913860C32@sourceware.org> Date: Tue, 6 Apr 2021 10:21:02 +0000 (GMT) X-BeenThere: cygwin-cvs@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin core component git logs List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 06 Apr 2021 10:21:02 -0000 https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=8bb5161fe3bdccbe94482715b71dd26d6d3e79e3 commit 8bb5161fe3bdccbe94482715b71dd26d6d3e79e3 Author: Takashi Yano Date: Tue Apr 6 09:40:13 2021 +0900 Cygwin: pty: Use atexit() instead of hooking exit() for GDB. - This patch utilizes atexit() instead of hooking exit() to clean up pseudo console stuff when debugging non-cygwin app using GDB. Diff: --- winsup/cygwin/fhandler.h | 2 +- winsup/cygwin/fhandler_tty.cc | 100 ++++++++++++++++++++++++++++-------------- winsup/cygwin/tty.cc | 2 + 3 files changed, 70 insertions(+), 34 deletions(-) diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h index 15fbd09b0..9df617b99 100644 --- a/winsup/cygwin/fhandler.h +++ b/winsup/cygwin/fhandler.h @@ -2374,7 +2374,7 @@ class fhandler_pty_slave: public fhandler_pty_common return fh; } bool setup_pseudoconsole (bool nopcon); - static void close_pseudoconsole (tty *ttyp); + static void close_pseudoconsole (tty *ttyp, DWORD force_switch_to = 0); bool term_has_pcon_cap (const WCHAR *env); void set_switch_to_pcon (void); void reset_switch_to_pcon (void); diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc index d78afb3ad..73aec2ade 100644 --- a/winsup/cygwin/fhandler_tty.cc +++ b/winsup/cygwin/fhandler_tty.cc @@ -147,11 +147,47 @@ set_switch_to_pcon (HANDLE *in, HANDLE *out, HANDLE *err, bool iscygwin) *err = replace_err->get_output_handle_nat (); } +static bool atexit_func_registered = false; +static bool debug_process = false; + +static void +atexit_func (void) +{ + if (isHybrid) + { + cygheap_fdenum cfd (false); + while (cfd.next () >= 0) + if (cfd->get_device () == (dev_t) myself->ctty) + { + DWORD force_switch_to = 0; + if (WaitForSingleObject (h_gdb_process, 0) == WAIT_TIMEOUT + && !debug_process) + force_switch_to = GetProcessId (h_gdb_process); + fhandler_base *fh = cfd; + fhandler_pty_slave *ptys = (fhandler_pty_slave *) fh; + tty *ttyp = ptys->get_ttyp (); + HANDLE from = ptys->get_handle_nat (); + HANDLE input_available_event = ptys->get_input_available_event (); + if (ttyp->getpgid () == myself->pgid + && GetStdHandle (STD_INPUT_HANDLE) == ptys->get_handle () + && ttyp->pcon_input_state_eq (tty::to_nat) && !force_switch_to) + { + WaitForSingleObject (ptys->input_mutex, INFINITE); + fhandler_pty_slave::transfer_input (tty::to_cyg, from, ttyp, + input_available_event); + ReleaseMutex (ptys->input_mutex); + } + ptys->close_pseudoconsole (ttyp, force_switch_to); + break; + } + CloseHandle (h_gdb_process); + } +} + #define DEF_HOOK(name) static __typeof__ (name) *name##_Orig /* CreateProcess() is hooked for GDB etc. */ DEF_HOOK (CreateProcessA); DEF_HOOK (CreateProcessW); -DEF_HOOK (exit); static BOOL WINAPI CreateProcessA_Hooked @@ -208,8 +244,15 @@ CreateProcessA_Hooked DuplicateHandle (GetCurrentProcess (), h_gdb_process, GetCurrentProcess (), &h_gdb_process, 0, 0, DUPLICATE_SAME_ACCESS); + debug_process = !!(f & (DEBUG_PROCESS | DEBUG_ONLY_THIS_PROCESS)); + if (!atexit_func_registered && !path.iscygexec ()) + { + atexit (atexit_func); + atexit_func_registered = true; + } return ret; } + static BOOL WINAPI CreateProcessW_Hooked (LPCWSTR n, LPWSTR c, LPSECURITY_ATTRIBUTES pa, LPSECURITY_ATTRIBUTES ta, @@ -265,36 +308,13 @@ CreateProcessW_Hooked DuplicateHandle (GetCurrentProcess (), h_gdb_process, GetCurrentProcess (), &h_gdb_process, 0, 0, DUPLICATE_SAME_ACCESS); - return ret; -} - -void -exit_Hooked (int e) -{ - if (isHybrid) + debug_process = !!(f & (DEBUG_PROCESS | DEBUG_ONLY_THIS_PROCESS)); + if (!atexit_func_registered && !path.iscygexec ()) { - cygheap_fdenum cfd (false); - while (cfd.next () >= 0) - if (cfd->get_device () == (dev_t) myself->ctty) - { - fhandler_base *fh = cfd; - fhandler_pty_slave *ptys = (fhandler_pty_slave *) fh; - tty *ttyp = ptys->get_ttyp (); - HANDLE from = ptys->get_handle_nat (); - HANDLE input_available_event = ptys->get_input_available_event (); - if (ttyp->getpgid () == myself->pgid - && GetStdHandle (STD_INPUT_HANDLE) == ptys->get_handle () - && ttyp->pcon_input_state_eq (tty::to_nat)) - { - WaitForSingleObject (ptys->input_mutex, INFINITE); - fhandler_pty_slave::transfer_input (tty::to_cyg, from, ttyp, - input_available_event); - ReleaseMutex (ptys->input_mutex); - } - break; - } + atexit (atexit_func); + atexit_func_registered = true; } - exit_Orig (e); + return ret; } static void @@ -1133,6 +1153,15 @@ fhandler_pty_slave::reset_switch_to_pcon (void) if (isHybrid) return; WaitForSingleObject (pcon_mutex, INFINITE); + HANDLE h; + if (get_ttyp ()->pcon_pid > MAX_PID && + (h = OpenProcess (SYNCHRONIZE, FALSE, get_ttyp ()->pcon_pid - MAX_PID))) + { + /* There is a process which is grabbing pseudo console. */ + CloseHandle (h); + ReleaseMutex (pcon_mutex); + return; + } if (get_ttyp ()->pcon_pid && get_ttyp ()->pcon_pid != myself->pid && !!pinfo (get_ttyp ()->pcon_pid)) { @@ -1140,6 +1169,7 @@ fhandler_pty_slave::reset_switch_to_pcon (void) ReleaseMutex (pcon_mutex); return; } + get_ttyp ()->pcon_input_state = tty::to_cyg; get_ttyp ()->pcon_pid = 0; get_ttyp ()->switch_to_pcon_in = false; get_ttyp ()->pcon_activated = false; @@ -2339,8 +2369,6 @@ fhandler_pty_slave::fixup_after_exec () /* CreateProcess() is hooked for GDB etc. */ DO_HOOK (NULL, CreateProcessA); DO_HOOK (NULL, CreateProcessW); - if (CreateProcessA_Orig || CreateProcessW_Orig) - DO_HOOK (NULL, exit); } /* This thread function handles the master control pipe. It waits for a @@ -3346,11 +3374,17 @@ fallback: /* The function close_pseudoconsole() should be static so that it can be called even after the fhandler_pty_slave instance is deleted. */ void -fhandler_pty_slave::close_pseudoconsole (tty *ttyp) +fhandler_pty_slave::close_pseudoconsole (tty *ttyp, DWORD force_switch_to) { DWORD switch_to_stub = 0, switch_to = 0; DWORD new_pcon_pid = 0; - if (ttyp->pcon_pid == myself->pid) + if (force_switch_to) + { + switch_to_stub = force_switch_to; + new_pcon_pid = force_switch_to + MAX_PID; + ttyp->setpgid (new_pcon_pid); + } + else if (ttyp->pcon_pid == myself->pid) { /* Search another process which attaches to the pseudo console */ DWORD current_pid = myself->exec_dwProcessId ?: myself->dwProcessId; diff --git a/winsup/cygwin/tty.cc b/winsup/cygwin/tty.cc index 5ed88d0e4..96acde387 100644 --- a/winsup/cygwin/tty.cc +++ b/winsup/cygwin/tty.cc @@ -402,5 +402,7 @@ tty::pcon_fg (pid_t pgid) if (p->ctty == ntty && p->pgid == pgid && p->exec_dwProcessId) return true; } + if (pgid > MAX_PID) + return true; return false; }