Make detection of unsafe calls to exit() optional and not default.

Reviewed by:	mbr

3 files changed, 56 insertions, 7 deletions

diff --git a/devel/linuxthreads/Makefile b/devel/linuxthreads/Makefile
index c59906b0cacc..757132aa2403 100644
--- a/devel/linuxthreads/Makefile
+++ b/devel/linuxthreads/Makefile
@@ -7,7 +7,7 @@
 
 PORTNAME=	linuxthreads
 PORTVERSION=	2.2.3
-PORTREVISION=	9
+PORTREVISION=	10
 CATEGORIES=	devel
 MASTER_SITES=	${MASTER_SITE_GNU}
 MASTER_SITE_SUBDIR=	glibc
@@ -30,6 +30,9 @@ MAKE_ENV+= USING_GCC3=true
 .if defined(INSTALL_LIBLTHREAD_PIC_ARCHIVE)
 MAKE_ENV+=	INSTALL_LIBLTHREAD_PIC_ARCHIVE=yes
 .endif
+.if defined(LINUXTHREADS_DETECT_UNSAFE_EXIT)
+MAKE_ENV+=	LINUXTHREADS_DETECT_UNSAFE_EXIT=yes
+.endif
 
 threads_files := README.FreeBSD clone.S clone.h freebsd-compat.h getgr_r.c \
 	gethostby_r.c getnetby_r.c getprotoby_r.c getpw_r.c getservby_r.c \
@@ -48,6 +51,13 @@ pre-fetch:
 	@${ECHO} WITH_CONDWAIT_PATCH
 	@${ECHO}
 .endif
+.if !defined(LINUXTHREADS_DETECT_UNSAFE_EXIT)
+	@${ECHO}
+	@${ECHO} "Some unsafe calls to exit() can be detected by defining"
+	@${ECHO} "LINUXTHREADS_DETECT_UNSAFE_EXIT, see files/README.FreeBSD"
+	@${ECHO} "for more info."
+	@${ECHO}
+.endif
 	@if ${TEST} -f /usr/src/gnu/lib/libgcc/Makefile; then \
 	  : ; \
 	else \
diff --git a/devel/linuxthreads/files/README.FreeBSD b/devel/linuxthreads/files/README.FreeBSD
index 8cd203c2dca7..31b59b43b2b4 100644
--- a/devel/linuxthreads/files/README.FreeBSD
+++ b/devel/linuxthreads/files/README.FreeBSD
@@ -90,3 +90,25 @@ set at 20 + 16 * MAXUSERS.
    initializers.  Linking the shared linuxthreads library before any such
    library causes the liblgcc_r.a version of those functions to be used.
    Use liblstdc++ and liblsupc++.
+
+4) Exit handling is broken.
+
+   If the linuxthreads library has been compiled with
+   LINUXTHREADS_DETECT_UNSAFE_EXIT defined in the ports makefile then
+   the library tries to avoid further calls to functions registered
+   with atexit if not called from the main thread or if other threads
+   were active.  Since this implicitly indicates a failure to do
+   proper cleanup, the exit code is then changed to 1.
+
+   If the linuxthreads library has been compiled without
+   LINUXTHREADS_DETECT_UNSAFE_EXIT, then calls to exit() has a
+   slightly higher probability of crashing or hanging the program when
+   other threads are active.  If another thread than the main thread
+   performs the exit call, the exit code will appear to be 0.
+
+   If multiple threads calls exit then the application will likely
+   crash.
+
+   If other threads has been joined by the main thread before it calls
+   exit then exit handling should be fairly safe and the correct exit
+   code can be detected by the parent process.
diff --git a/devel/linuxthreads/files/patch-aa b/devel/linuxthreads/files/patch-aa
index ecb387fc7983..e0a30bfaa397 100644
--- a/devel/linuxthreads/files/patch-aa
+++ b/devel/linuxthreads/files/patch-aa
@@ -13,7 +13,7 @@ diff -ru ../../work/linuxthreads-2.2.3/Examples/Makefile ./Examples/Makefile
 diff -ru ../../work/linuxthreads-2.2.3/Makefile ./Makefile
 --- ../../work/linuxthreads-2.2.3/Makefile	Wed Apr 25 21:50:59 2001
 +++ ./Makefile	Thu Jun  7 23:13:52 2001
-@@ -1,128 +1,88 @@
+@@ -1,128 +1,91 @@
 -# Copyright (C) 1996,1997,1998,1999,2000,2001 Free Software Foundation, Inc.
 -# This file is part of the GNU C Library.
 +LIB=lthread
@@ -57,6 +57,9 @@ diff -ru ../../work/linuxthreads-2.2.3/Makefile ./Makefile
 +CFLAGS += -DLINUXTHREADS 
 +CFLAGS += -D__USE_UNIX98
 +CFLAGS += -D__USE_XOPEN2K -D_STACK_GROWS_DOWN -DNEWLIBC -D_THREAD_SAFE
++.if defined(LINUXTHREADS_DETECT_UNSAFE_EXIT)
++CFLAGS += -DLINUXTHREADS_DETECT_UNSAFE_EXIT
++.endif
 +
 +AINC = -I${LIBSRC_BASE}/libc/${MACHINE_ARCH} -I${.CURDIR}/sysdeps/${MACHINE_ARCH}
 +
@@ -513,32 +516,38 @@ diff -ru ../../work/linuxthreads-2.2.3/manager.c ./manager.c
        detached = th->p_detached;
        __pthread_unlock(th->p_lock);
        if (detached)
-@@ -834,10 +857,16 @@
+@@ -834,10 +857,20 @@
  
  /* Process-wide exit() */
  
++#ifdef LINUXTHREADS_DETECT_UNSAFE_EXIT
 +extern int __pthread_exit_requested_bymainthread;
 +extern int __pthread_exit_alone;
++#endif
 +
  static void pthread_handle_exit(pthread_descr issuing_thread, int exitcode)
  {
    pthread_descr th;
    __pthread_exit_requested = 1;
++#ifdef LINUXTHREADS_DETECT_UNSAFE_EXIT
 +  __pthread_exit_alone = 1;
 +  if (issuing_thread == __pthread_main_thread)
 +    __pthread_exit_requested_bymainthread = 1;
++#endif
    __pthread_exit_code = exitcode;
    /* Send the CANCEL signal to all running threads, including the main
       thread, but excluding the thread from which the exit request originated
-@@ -846,6 +875,11 @@
+@@ -846,6 +875,13 @@
    for (th = issuing_thread->p_nextlive;
         th != issuing_thread;
         th = th->p_nextlive) {
++#ifdef LINUXTHREADS_DETECT_UNSAFE_EXIT
 +    /* Cancelled thread might have been in critical region unless terminated */
 +    if (th->p_terminated == 0) {
 +      __pthread_exit_alone = 0;
 +      __pthread_exit_code = 1;
 +    }
++#endif
      kill(th->p_pid, __pthread_sig_cancel);
    }
    /* Now, wait for all these threads, so that they don't become zombies
@@ -650,12 +659,14 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
    __ATOMIC_INITIALIZER,       /* struct pthread_atomic p_resume_count */
    0,                          /* char p_woken_by_cancel */
    0,                          /* char p_condvar_avail */
-@@ -185,6 +195,8 @@
+@@ -185,6 +195,10 @@
  /* For process-wide exit() */
  
  int __pthread_exit_requested;
++#ifdef LINUXTHREADS_DETECT_UNSAFE_EXIT
 +int __pthread_exit_requested_bymainthread = 0;
 +int __pthread_exit_alone = 1;
++#endif
  int __pthread_exit_code;
  
  /* Maximum stack size.  */
@@ -816,10 +827,11 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
      __libc_write(__pthread_manager_request,
  		 (char *) &request, sizeof(request));
      suspend(self);
-@@ -768,25 +759,30 @@
+@@ -768,25 +759,34 @@
      if (self == __pthread_main_thread)
        {
  	waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE);
++#ifdef LINUXTHREADS_DETECT_UNSAFE_EXIT
 +	/*
 +	 * If other threads have been canceled then proper cleanup
 +	 * cannot be performed since a canceled thread might have
@@ -828,9 +840,11 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
 +	 */
 +	if (__pthread_exit_alone == 0)
 +	  _exit(1);
++#endif
  	free (__pthread_manager_thread_bos);
  	__pthread_manager_thread_bos = __pthread_manager_thread_tos = NULL;
        }
++#ifdef LINUXTHREADS_DETECT_UNSAFE_EXIT
 +    /*
 +     * If other threads have been canceled then proper cleanup
 +     * cannot be performed since a canceled thread might have
@@ -841,6 +855,7 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
 +      __pthread_exit_code = 1;
 +      _exit(1);
 +    }
++#endif
    }
  }
  
@@ -860,13 +875,15 @@ diff -ru ../../work/linuxthreads-2.2.3/pthread.c ./pthread.c
  
  /* The handler for the RESTART signal just records the signal received
     in the thread descriptor, and optionally performs a siglongjmp
-@@ -818,6 +812,9 @@
+@@ -818,6 +812,11 @@
    if (__builtin_expect (__pthread_exit_requested, 0)) {
      /* Main thread should accumulate times for thread manager and its
         children, so that timings for main thread account for all threads. */
++#ifdef LINUXTHREADS_DETECT_UNSAFE_EXIT
 +    if (self == __pthread_main_thread &&
 +	__pthread_exit_requested_bymainthread != 0)
 +	    return;
++#endif
      if (self == __pthread_main_thread)
        waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE);
      _exit(__pthread_exit_code);