Test for correct setting of errno.

This patch adds tests for POSIX and Linux specific syscalls
that implemented with syscall templates machinery. The reason
of tests is to receive the expected error code and test if
it's handled properly by glibc.

2017-03-08  Yury Norov <ynorov@caviumnetworks.com>
	    Zack Weinberg  <zackw@panix.com>

	* posix/test-errno.c: New file.
	* posix/Makefile (tests): Add test-errno.
	* sysdeps/unix/sysv/linux/test-errno.c: New file.
	* sysdeps/unix/sysv/linux/Makefile (tests): Add test-errno.

2 files changed, 143 insertions, 1 deletions

diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index fc29c54c86..6b7aa3fdf8 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -43,7 +43,7 @@ sysdep_headers += sys/mount.h sys/acct.h sys/sysctl.h \
 		  bits/mman-linux.h
 
 tests += tst-clone tst-clone2 tst-fanotify tst-personality tst-quota \
-	 tst-sync_file_range
+	 tst-sync_file_range test-errno
 
 # Generate the list of SYS_* macros for the system calls (__NR_* macros).
 
diff --git a/sysdeps/unix/sysv/linux/test-errno.c b/sysdeps/unix/sysv/linux/test-errno.c
new file mode 100644
index 0000000000..ab3735fe87
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/test-errno.c
@@ -0,0 +1,142 @@
+/* Test that failing system calls do set errno to the correct value.
+
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <mqueue.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/epoll.h>
+#include <sys/eventfd.h>
+#include <sys/file.h>
+#include <sys/fsuid.h>
+#include <sys/inotify.h>
+#include <sys/mman.h>
+#include <sys/poll.h>
+#include <sys/quota.h>
+#include <sys/resource.h>
+#include <sys/select.h>
+#include <sys/sendfile.h>
+#include <sys/swap.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+/* This is not an exhaustive test: only system calls that can be
+   persuaded to fail with a consistent error code and no side effects
+   are included.  Usually these are failures due to invalid arguments,
+   with errno code EBADF or EINVAL.  The order of argument checks is
+   unspecified, so we must take care to provide arguments that only
+   allow _one_ failure mode.
+
+   Note that all system calls that can fail with EFAULT are permitted
+   to deliver a SIGSEGV signal instead, so we avoid supplying invalid
+   pointers in general, and we do not attempt to test system calls
+   that can only fail with EFAULT (e.g. gettimeofday, gethostname).
+
+   Also note that root-only system calls (e.g. acct, reboot) may, when
+   the test is run as an unprivileged user, fail due to insufficient
+   privileges before bothering to do argument checks, so those are not
+   tested either.
+
+   Also, system calls that take enum or a set of flags as argument is
+   not tested if POSIX doesn't specify exact binary values for all
+   flags, and so any value passed to flags may become valid.
+
+   Some tests assume "/bin/sh" names a file that exists and is not a
+   directory.  */
+
+#define test_wrp_rv(rtype, prtype, experr, syscall, ...)	\
+  (__extension__ ({						\
+    errno = 0xdead;						\
+    rtype ret = syscall (__VA_ARGS__);				\
+    int err = errno;						\
+    int fail;							\
+    if (ret == (rtype) -1 && err == experr)			\
+      fail = 0;							\
+    else							\
+      {								\
+        fail = 1;						\
+        if (ret != (rtype) -1)					\
+          printf ("FAIL: " #syscall ": didn't fail as expected"	\
+               " (return "prtype")\n", ret);			\
+        else if (err == 0xdead)					\
+          puts("FAIL: " #syscall ": didn't update errno\n");	\
+        else if (err != experr)					\
+          printf ("FAIL: " #syscall				\
+               ": errno is: %d (%s) expected: %d (%s)\n",	\
+               err, strerror (err), experr, strerror (experr));	\
+      }								\
+    fail;							\
+  }))
+
+#define test_wrp(experr, syscall, ...)				\
+  test_wrp_rv(int, "%d", experr, syscall, __VA_ARGS__)
+
+static int
+do_test (void)
+{
+  fd_set rs, ws, es;
+  int status;
+  off_t off;
+  stack_t ss;
+  struct dqblk dqblk;
+  struct epoll_event epoll_event;
+  struct pollfd pollfd;
+  struct sched_param sch_param;
+  struct timespec ts;
+  struct timeval tv;
+  unsigned char vec[16];
+  ss.ss_flags = ~SS_DISABLE;
+  ts.tv_sec = -1;
+
+  int fails = 0;
+  fails |= test_wrp (EINVAL, epoll_create, -1);
+  fails |= test_wrp (EINVAL, epoll_create1, EPOLL_CLOEXEC + 1);
+  fails |= test_wrp (EBADF, epoll_ctl, -1, EPOLL_CTL_ADD, 0, &epoll_event);
+  fails |= test_wrp (EBADF, epoll_wait, -1, &epoll_event, 1, 1);
+  fails |= test_wrp (EBADF, fdatasync, -1);
+  fails |= test_wrp (EBADF, flock, -1, LOCK_SH);
+  fails |= test_wrp (ESRCH, getpgid, -1);
+  fails |= test_wrp (EINVAL, inotify_add_watch, -1, "/", 0);
+  fails |= test_wrp (EINVAL, mincore, (void *) -1, 0, vec);
+  fails |= test_wrp (EINVAL, mlock, (void *) -1, 1); // different errors
+  fails |= test_wrp (EINVAL, nanosleep, &ts, &ts);
+  fails |= test_wrp (EINVAL, poll, &pollfd, -1, 0);
+  fails |= test_wrp (ENODEV, quotactl, Q_GETINFO, NULL, -1, (caddr_t) &dqblk);
+  fails |= test_wrp (EINVAL, sched_getparam, -1, &sch_param);
+  fails |= test_wrp (EINVAL, sched_getscheduler, -1);
+  fails |= test_wrp (EINVAL, sched_get_priority_max, -1);
+  fails |= test_wrp (EINVAL, sched_get_priority_min, -1);
+  fails |= test_wrp (EINVAL, sched_rr_get_interval, -1, &ts);
+  fails |= test_wrp (EINVAL, sched_setparam, -1, &sch_param);
+  fails |= test_wrp (EINVAL, sched_setscheduler, -1, 0, &sch_param);
+  fails |= test_wrp (EINVAL, select, -1, &rs, &ws, &es, &tv);
+  fails |= test_wrp (EBADF, sendfile, -1, -1, &off, 0);
+  fails |= test_wrp (EINVAL, sigaltstack, &ss, NULL);
+  fails |= test_wrp (ECHILD, wait4, -1, &status, 0, NULL);
+
+  return fails;
+}
+
+#include "support/test-driver.c"