Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 122 insertions, 0 deletions

diff --git a/REORG.TODO/inet/deadline.c b/REORG.TODO/inet/deadline.c
new file mode 100644
index 0000000000..c1fa415a39
--- /dev/null
+++ b/REORG.TODO/inet/deadline.c
@@ -0,0 +1,122 @@
+/* Computing deadlines for timeouts.
+   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 <net-internal.h>
+
+#include <assert.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <time.h>
+
+struct deadline_current_time internal_function
+__deadline_current_time (void)
+{
+  struct deadline_current_time result;
+  if (__clock_gettime (CLOCK_MONOTONIC, &result.current) != 0)
+    {
+      struct timeval current_tv;
+      if (__gettimeofday (&current_tv, NULL) == 0)
+        __libc_fatal ("Fatal error: gettimeofday system call failed\n");
+      result.current.tv_sec = current_tv.tv_sec;
+      result.current.tv_nsec = current_tv.tv_usec * 1000;
+    }
+  assert (result.current.tv_sec >= 0);
+  return result;
+}
+
+/* A special deadline value for which __deadline_is_infinite is
+   true.  */
+static inline struct deadline
+infinite_deadline (void)
+{
+  return (struct deadline) { { -1, -1 } };
+}
+
+struct deadline internal_function
+__deadline_from_timeval (struct deadline_current_time current,
+                         struct timeval tv)
+{
+  assert (__is_timeval_valid_timeout (tv));
+
+  /* Compute second-based deadline.  Perform the addition in
+     uintmax_t, which is unsigned, to simply overflow detection.  */
+  uintmax_t sec = current.current.tv_sec;
+  sec += tv.tv_sec;
+  if (sec < (uintmax_t) tv.tv_sec)
+    return infinite_deadline ();
+
+  /* Compute nanosecond deadline.  */
+  int nsec = current.current.tv_nsec + tv.tv_usec * 1000;
+  if (nsec >= 1000 * 1000 * 1000)
+    {
+      /* Carry nanosecond overflow to seconds.  */
+      nsec -= 1000 * 1000 * 1000;
+      if (sec + 1 < sec)
+        return infinite_deadline ();
+      ++sec;
+    }
+  /* This uses a GCC extension, otherwise these casts for detecting
+     overflow would not be defined.  */
+  if ((time_t) sec < 0 || sec != (uintmax_t) (time_t) sec)
+    return infinite_deadline ();
+
+  return (struct deadline) { { sec, nsec } };
+}
+
+int internal_function
+__deadline_to_ms (struct deadline_current_time current,
+                  struct deadline deadline)
+{
+  if (__deadline_is_infinite (deadline))
+    return INT_MAX;
+
+  if (current.current.tv_sec > deadline.absolute.tv_sec
+      || (current.current.tv_sec == deadline.absolute.tv_sec
+          && current.current.tv_nsec >= deadline.absolute.tv_nsec))
+    return 0;
+  time_t sec = deadline.absolute.tv_sec - current.current.tv_sec;
+  if (sec >= INT_MAX)
+    /* This value will overflow below.  */
+    return INT_MAX;
+  int nsec = deadline.absolute.tv_nsec - current.current.tv_nsec;
+  if (nsec < 0)
+    {
+      /* Borrow from the seconds field.  */
+      assert (sec > 0);
+      --sec;
+      nsec += 1000 * 1000 * 1000;
+    }
+
+  /* Prepare for rounding up to milliseconds.  */
+  nsec += 999999;
+  if (nsec > 1000 * 1000 * 1000)
+    {
+      assert (sec < INT_MAX);
+      ++sec;
+      nsec -= 1000 * 1000 * 1000;
+    }
+
+  unsigned int msec = nsec / (1000 * 1000);
+  if (sec > INT_MAX / 1000)
+    return INT_MAX;
+  msec += sec * 1000;
+  if (msec > INT_MAX)
+    return INT_MAX;
+  return msec;
+}