nptl: Move futex-internal.c into main nptl directory

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

2 files changed, 129 insertions, 0 deletions

diff --git a/nptl/Makefile b/nptl/Makefile
index 94c3873623..5a7558d943 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -97,6 +97,7 @@ libpthread-routines = \
   flockfile \
   ftrylockfile \
   funlockfile \
+  futex-internal \
   herrno \
   libpthread-compat \
   lowlevellock \
@@ -314,6 +315,8 @@ CFLAGS-fsync.c += -fexceptions -fasynchronous-unwind-tables
 
 CFLAGS-pt-system.c += -fexceptions
 
+CFLAGS-futex-internal.c += -fexceptions -fasynchronous-unwind-tables
+
 LDLIBS-tst-once5 = -lstdc++
 CFLAGS-tst-thread_local1.o = -std=gnu++11
 LDLIBS-tst-thread_local1 = -lstdc++
diff --git a/nptl/futex-internal.c b/nptl/futex-internal.c
new file mode 100644
index 0000000000..89b4ba76e9
--- /dev/null
+++ b/nptl/futex-internal.c
@@ -0,0 +1,126 @@
+/* futex helper functions for glibc-internal use.
+   Copyright (C) 2020-2021 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
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sysdep.h>
+#include <time.h>
+#include <futex-internal.h>
+#include <kernel-features.h>
+
+#ifndef __ASSUME_TIME64_SYSCALLS
+static int
+__futex_abstimed_wait_common32 (unsigned int* futex_word,
+                                unsigned int expected, int op,
+                                const struct __timespec64* abstime,
+                                int private, bool cancel)
+{
+  struct timespec ts32, *pts32 = NULL;
+  if (abstime != NULL)
+    {
+      if (! in_time_t_range (abstime->tv_sec))
+	return -EOVERFLOW;
+
+      ts32 = valid_timespec64_to_timespec (*abstime);
+      pts32 = &ts32;
+    }
+
+  if (cancel)
+    return INTERNAL_SYSCALL_CANCEL (futex, futex_word, op, expected,
+                                    pts32, NULL /* Unused.  */,
+                                    FUTEX_BITSET_MATCH_ANY);
+  else
+    return INTERNAL_SYSCALL_CALL (futex, futex_word, op, expected,
+                                  pts32, NULL /* Unused.  */,
+                                  FUTEX_BITSET_MATCH_ANY);
+}
+#endif /* ! __ASSUME_TIME64_SYSCALLS */
+
+static int
+__futex_abstimed_wait_common64 (unsigned int* futex_word,
+                                unsigned int expected, clockid_t clockid,
+                                const struct __timespec64* abstime,
+                                int private, bool cancel)
+{
+  unsigned int clockbit;
+  int err;
+
+  /* Work around the fact that the kernel rejects negative timeout values
+     despite them being valid.  */
+  if (__glibc_unlikely ((abstime != NULL) && (abstime->tv_sec < 0)))
+    return ETIMEDOUT;
+
+  if (! lll_futex_supported_clockid (clockid))
+    return EINVAL;
+
+  clockbit = (clockid == CLOCK_REALTIME) ? FUTEX_CLOCK_REALTIME : 0;
+  int op = __lll_private_flag (FUTEX_WAIT_BITSET | clockbit, private);
+
+  if (cancel)
+    err = INTERNAL_SYSCALL_CANCEL (futex_time64, futex_word, op, expected,
+                                   abstime, NULL /* Unused.  */,
+                                   FUTEX_BITSET_MATCH_ANY);
+  else
+    err = INTERNAL_SYSCALL_CALL (futex_time64, futex_word, op, expected,
+                                 abstime, NULL /* Ununsed.  */,
+                                 FUTEX_BITSET_MATCH_ANY);
+#ifndef __ASSUME_TIME64_SYSCALLS
+  if (err == -ENOSYS)
+    err = __futex_abstimed_wait_common32 (futex_word, expected, op, abstime,
+                                          private, cancel);
+#endif
+
+  switch (err)
+    {
+    case 0:
+    case -EAGAIN:
+    case -EINTR:
+    case -ETIMEDOUT:
+    case -EINVAL:
+    case -EOVERFLOW:  /* Passed absolute timeout uses 64 bit time_t type, but
+                         underlying kernel does not support 64 bit time_t futex
+                         syscalls.  */
+      return -err;
+
+    case -EFAULT: /* Must have been caused by a glibc or application bug.  */
+    case -ENOSYS: /* Must have been caused by a glibc bug.  */
+    /* No other errors are documented at this time.  */
+    default:
+      futex_fatal_error ();
+    }
+}
+
+int
+__futex_abstimed_wait64 (unsigned int* futex_word, unsigned int expected,
+                         clockid_t clockid,
+                         const struct __timespec64* abstime, int private)
+{
+  return __futex_abstimed_wait_common64 (futex_word, expected, clockid,
+                                         abstime, private, false);
+}
+libpthread_hidden_def (__futex_abstimed_wait64)
+
+int
+__futex_abstimed_wait_cancelable64 (unsigned int* futex_word,
+                                    unsigned int expected, clockid_t clockid,
+                                    const struct __timespec64* abstime,
+                                    int private)
+{
+  return __futex_abstimed_wait_common64 (futex_word, expected, clockid,
+                                         abstime, private, true);
+}
+libpthread_hidden_def (__futex_abstimed_wait_cancelable64)