[src/trunk]: src/lib/libpthread Pass down errno when calling pthread__errorfu...

[joerg <joerg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e9899e2eb010
branches:  trunk
changeset: 933978:e9899e2eb010
user:      joerg <joerg%NetBSD.org@localhost>
date:      Tue Jun 02 00:29:53 2020 +0000

description:
Pass down errno when calling pthread__errorfunc after a system call.
Allow format arguments for that reason and use (v)snprintf_ss in
pthread_errorfunc to avoid race conditions and the like.

diffstat:

 lib/libpthread/pthread.c        |  22 ++++++++++++++--------
 lib/libpthread/pthread_int.h    |   6 +++---
 lib/libpthread/pthread_rwlock.c |   6 +++---
 3 files changed, 20 insertions(+), 14 deletions(-)

diffs (125 lines):

diff -r 7d0ade462c50 -r e9899e2eb010 lib/libpthread/pthread.c
--- a/lib/libpthread/pthread.c  Mon Jun 01 22:58:06 2020 +0000
+++ b/lib/libpthread/pthread.c  Tue Jun 02 00:29:53 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pthread.c,v 1.171 2020/06/01 11:44:59 ad Exp $ */
+/*     $NetBSD: pthread.c,v 1.172 2020/06/02 00:29:53 joerg Exp $      */
 
 /*-
  * Copyright (c) 2001, 2002, 2003, 2006, 2007, 2008, 2020
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: pthread.c,v 1.171 2020/06/01 11:44:59 ad Exp $");
+__RCSID("$NetBSD: pthread.c,v 1.172 2020/06/02 00:29:53 joerg Exp $");
 
 #define        __EXPOSE_STACK  1
 
@@ -622,7 +622,7 @@
                self->pt_nwaiters = 0;
                if (rv != 0) {
                        pthread__errorfunc(__FILE__, __LINE__, __func__,
-                           "_lwp_unpark failed");
+                           "_lwp_unpark failed: %d", errno);
                }
                break;
        default:
@@ -631,7 +631,7 @@
                self->pt_nwaiters = 0;
                if (rv != 0) {
                        pthread__errorfunc(__FILE__, __LINE__, __func__,
-                           "_lwp_unpark_all failed");
+                           "_lwp_unpark_all failed: %d", errno);
                }
                break;
        }
@@ -1102,23 +1102,29 @@
 
 void
 pthread__errorfunc(const char *file, int line, const char *function,
-                  const char *msg)
+                  const char *msg, ...)
 {
        char buf[1024];
+       char buf2[1024];
        size_t len;
+       va_list ap;
 
        if (pthread__diagassert == 0)
                return;
 
+       va_start(ap, msg);
+       vsnprintf_ss(buf2, sizeof(buf2), msg, ap);
+       va_end(ap);
+
        /*
         * snprintf should not acquire any locks, or we could
         * end up deadlocked if the assert caller held locks.
         */
-       len = snprintf(buf, 1024,
+       len = snprintf_ss(buf, sizeof(buf),
            "%s: Error detected by libpthread: %s.\n"
            "Detected by file \"%s\", line %d%s%s%s.\n"
            "See pthread(3) for information.\n",
-           getprogname(), msg, file, line,
+           getprogname(), buf2, file, line,
            function ? ", function \"" : "",
            function ? function : "",
            function ? "\"" : "");
@@ -1195,7 +1201,7 @@
                                break;
                        default:
                                pthread__errorfunc(__FILE__, __LINE__,
-                                   __func__, "_lwp_park failed");
+                                   __func__, "_lwp_park failed: %d", errno);
                                break;
                        }
                }
diff -r 7d0ade462c50 -r e9899e2eb010 lib/libpthread/pthread_int.h
--- a/lib/libpthread/pthread_int.h      Mon Jun 01 22:58:06 2020 +0000
+++ b/lib/libpthread/pthread_int.h      Tue Jun 02 00:29:53 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pthread_int.h,v 1.105 2020/06/01 11:44:59 ad Exp $     */
+/*     $NetBSD: pthread_int.h,v 1.106 2020/06/02 00:29:53 joerg Exp $  */
 
 /*-
  * Copyright (c) 2001, 2002, 2003, 2006, 2007, 2008, 2020
@@ -300,8 +300,8 @@
 
 __dead void    pthread__assertfunc(const char *, int, const char *, const char *)
                            PTHREAD_HIDE;
-void   pthread__errorfunc(const char *, int, const char *, const char *)
-                          PTHREAD_HIDE;
+void   pthread__errorfunc(const char *, int, const char *, const char *, ...)
+                           __printflike(4, 5) PTHREAD_HIDE;
 char   *pthread__getenv(const char *) PTHREAD_HIDE;
 __dead void    pthread__cancelled(void) PTHREAD_HIDE;
 void   pthread__mutex_deferwake(pthread_t, pthread_mutex_t *) PTHREAD_HIDE;
diff -r 7d0ade462c50 -r e9899e2eb010 lib/libpthread/pthread_rwlock.c
--- a/lib/libpthread/pthread_rwlock.c   Mon Jun 01 22:58:06 2020 +0000
+++ b/lib/libpthread/pthread_rwlock.c   Tue Jun 02 00:29:53 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pthread_rwlock.c,v 1.41 2020/06/01 11:44:59 ad Exp $ */
+/*     $NetBSD: pthread_rwlock.c,v 1.42 2020/06/02 00:29:53 joerg Exp $ */
 
 /*-
  * Copyright (c) 2002, 2006, 2007, 2008, 2020 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: pthread_rwlock.c,v 1.41 2020/06/01 11:44:59 ad Exp $");
+__RCSID("$NetBSD: pthread_rwlock.c,v 1.42 2020/06/02 00:29:53 joerg Exp $");
 
 #include <sys/types.h>
 #include <sys/lwpctl.h>
@@ -361,7 +361,7 @@
                        return error;
 
                pthread__errorfunc(__FILE__, __LINE__, __func__,
-                   "direct handoff failure");
+                   "direct handoff failure: %d", errno);
        }
 }