X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=ncurses%2Ftty%2Flib_tstp.c;h=8624b7604e78c8f0c3e0699be0d2b80fb4324110;hp=6ccdfc74a27f631db6244d408dcb8de351fa68f1;hb=7d3e03f12f3e179f5780f733fa5b78d981080d48;hpb=48c8a4fe456e83238533fb42b36fd5253db22f59

diff --git a/ncurses/tty/lib_tstp.c b/ncurses/tty/lib_tstp.c
index 6ccdfc74..8624b760 100644
--- a/ncurses/tty/lib_tstp.c
+++ b/ncurses/tty/lib_tstp.c
@@ -1,5 +1,5 @@
 /****************************************************************************
- * Copyright (c) 1998-2010,2011 Free Software Foundation, Inc.              *
+ * Copyright (c) 1998-2013,2014 Free Software Foundation, Inc.              *
  *                                                                          *
  * Permission is hereby granted, free of charge, to any person obtaining a  *
  * copy of this software and associated documentation files (the            *
@@ -42,7 +42,7 @@
 
 #include <SigAction.h>
 
-MODULE_ID("$Id: lib_tstp.c,v 1.42 2011/04/16 16:42:10 tom Exp $")
+MODULE_ID("$Id: lib_tstp.c,v 1.48 2014/04/26 18:47:35 juergen Exp $")
 
 #if defined(SIGTSTP) && (HAVE_SIGACTION || HAVE_SIGVEC)
 #define USE_SIGTSTP 1
@@ -134,7 +134,7 @@ signal_name(int sig)
 
 #if USE_SIGTSTP
 static void
-tstp(int dummy GCC_UNUSED)
+handle_SIGTSTP(int dummy GCC_UNUSED)
 {
     SCREEN *sp = CURRENT_SCREEN;
     sigset_t mask, omask;
@@ -144,7 +144,8 @@ tstp(int dummy GCC_UNUSED)
     int sigttou_blocked;
 #endif
 
-    T(("tstp() called"));
+    _nc_globals.have_sigtstp = 1;
+    T(("handle_SIGTSTP() called"));
 
     /*
      * The user may have changed the prog_mode tty bits, so save them.
@@ -235,21 +236,24 @@ tstp(int dummy GCC_UNUSED)
 #endif /* USE_SIGTSTP */
 
 static void
-cleanup(int sig)
+handle_SIGINT(int sig)
 {
     SCREEN *sp = CURRENT_SCREEN;
 
     /*
-     * Actually, doing any sort of I/O from within an signal handler is
-     * "unsafe".  But we'll _try_ to clean up the screen and terminal
-     * settings on the way out.
+     * Much of this is unsafe from a signal handler.  But we'll _try_ to clean
+     * up the screen and terminal settings on the way out.
+     *
+     * There are at least the following problems:
+     * 1) Walking the SCREEN list is unsafe, since all list management
+     *    is done without any signal blocking.
+     * 2) On systems which have REENTRANT turned on, set_term() uses
+     *    _nc_lock_global() which could deadlock or misbehave in other ways.
+     * 3) endwin() calls all sorts of stuff, many of which use stdio or
+     *    other library functions which are clearly unsafe.
      */
     if (!_nc_globals.cleanup_nested++
-	&& (sig == SIGINT
-#ifdef SIGQUIT
-	    || sig == SIGQUIT
-#endif
-	)) {
+	&& (sig == SIGINT || sig == SIGTERM)) {
 #if HAVE_SIGACTION || HAVE_SIGVEC
 	sigaction_t act;
 	sigemptyset(&act.sa_mask);
@@ -263,23 +267,22 @@ cleanup(int sig)
 	    SCREEN *scan;
 	    for (each_screen(scan)) {
 		if (scan->_ofp != 0
-		    && isatty(fileno(scan->_ofp))) {
-		    scan->_cleanup = TRUE;
+		    && NC_ISATTY(fileno(scan->_ofp))) {
 		    scan->_outch = NCURSES_SP_NAME(_nc_outch);
 		}
 		set_term(scan);
 		NCURSES_SP_NAME(endwin) (NCURSES_SP_ARG);
 		if (sp)
-		    sp->_endwin = FALSE;	/* in case we have an atexit! */
+		    sp->_endwin = FALSE;	/* in case of reuse */
 	    }
 	}
     }
-    exit(EXIT_FAILURE);
+    _exit(EXIT_FAILURE);
 }
 
 #if USE_SIGWINCH
 static void
-sigwinch(int sig GCC_UNUSED)
+handle_SIGWINCH(int sig GCC_UNUSED)
 {
     _nc_globals.have_sigwinch = 1;
 # if USE_PTHREADS_EINTR
@@ -297,7 +300,7 @@ sigwinch(int sig GCC_UNUSED)
  * handler.
  */
 static int
-CatchIfDefault(int sig, RETSIGTYPE (*handler) (int))
+CatchIfDefault(int sig, void (*handler) (int))
 {
     int result;
 #if HAVE_SIGACTION || HAVE_SIGVEC
@@ -327,7 +330,7 @@ CatchIfDefault(int sig, RETSIGTYPE (*handler) (int))
 	result = FALSE;
     }
 #else /* !HAVE_SIGACTION */
-    RETSIGTYPE (*ohandler) (int);
+    void (*ohandler) (int);
 
     ohandler = signal(sig, SIG_IGN);
     if (ohandler == SIG_DFL
@@ -360,7 +363,7 @@ CatchIfDefault(int sig, RETSIGTYPE (*handler) (int))
  * the caller later changes its mind, but that doesn't seem correct.
  */
 NCURSES_EXPORT(void)
-_nc_signal_handler(bool enable)
+_nc_signal_handler(int enable)
 {
     T((T_CALLED("_nc_signal_handler(%d)"), enable));
 #if USE_SIGTSTP			/* Xenix 2.x doesn't have SIGTSTP, for example */
@@ -381,7 +384,7 @@ _nc_signal_handler(bool enable)
 #ifdef SA_RESTART
 		new_sigaction.sa_flags |= SA_RESTART;
 #endif /* SA_RESTART */
-		new_sigaction.sa_handler = tstp;
+		new_sigaction.sa_handler = handle_SIGTSTP;
 		(void) sigaction(SIGTSTP, &new_sigaction, NULL);
 	    } else {
 		ignore_tstp = TRUE;
@@ -392,10 +395,10 @@ _nc_signal_handler(bool enable)
 
     if (!_nc_globals.init_signals) {
 	if (enable) {
-	    CatchIfDefault(SIGINT, cleanup);
-	    CatchIfDefault(SIGTERM, cleanup);
+	    CatchIfDefault(SIGINT, handle_SIGINT);
+	    CatchIfDefault(SIGTERM, handle_SIGINT);
 #if USE_SIGWINCH
-	    CatchIfDefault(SIGWINCH, sigwinch);
+	    CatchIfDefault(SIGWINCH, handle_SIGWINCH);
 #endif
 	    _nc_globals.init_signals = TRUE;
 	}