vppinfra: remove unused historical code

"timer.[ch]" used a signal handler to deliver timer callbacks. Without
indulging in a set of sigprocmask(...) system calls, it would be
unsafe to use the mechanism.

Rather than wait for another developer to accidentally open this
particular can of worms, best to remove the code. It's nothing more
than an attractive nuisance at this point.

Type: refactor
Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: Ia3e7b00a389c302b466605dff0c1bf3566b8dbbd

3 files changed, 0 insertions, 375 deletions

diff --git a/src/vppinfra/CMakeLists.txt b/src/vppinfra/CMakeLists.txt
index 6c231bdf77b..c6a55b3e55f 100644
--- a/src/vppinfra/CMakeLists.txt
+++ b/src/vppinfra/CMakeLists.txt
@@ -72,7 +72,6 @@ set(VPPINFRA_SRCS
   string.c
   time.c
   time_range.c
-  timer.c
   timing_wheel.c
   tw_timer_2t_1w_2048sl.c
   tw_timer_16t_2w_512sl.c
@@ -159,7 +158,6 @@ set(VPPINFRA_HEADERS
   string.h
   time.h
   time_range.h
-  timer.h
   timing_wheel.h
   tw_timer_16t_1w_2048sl.h
   tw_timer_16t_2w_512sl.h
diff --git a/src/vppinfra/timer.c b/src/vppinfra/timer.c
deleted file mode 100644
index e1e32eb285f..00000000000
--- a/src/vppinfra/timer.c
+++ /dev/null
@@ -1,327 +0,0 @@
-/*
- * Copyright (c) 2015 Cisco and/or its affiliates.
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at:
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-/*
-  Copyright (c) 2001, 2002, 2003 Eliot Dresselhaus
-
-  Permission is hereby granted, free of charge, to any person obtaining
-  a copy of this software and associated documentation files (the
-  "Software"), to deal in the Software without restriction, including
-  without limitation the rights to use, copy, modify, merge, publish,
-  distribute, sublicense, and/or sell copies of the Software, and to
-  permit persons to whom the Software is furnished to do so, subject to
-  the following conditions:
-
-  The above copyright notice and this permission notice shall be
-  included in all copies or substantial portions of the Software.
-
-  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-*/
-
-#include <math.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/param.h>
-
-#include <vppinfra/vec.h>
-#include <vppinfra/smp.h>
-#include <vppinfra/time.h>
-#include <vppinfra/timer.h>
-#include <vppinfra/error.h>
-
-#ifndef HZ
-#define HZ 1000
-#endif
-
-typedef struct
-{
-  f64 time;
-  timer_func_t *func;
-  any arg;
-} timer_callback_t;
-
-/* Vector of currently unexpired timers. */
-static timer_callback_t *timers;
-
-/* Convert time from 64bit floating format to struct timeval. */
-always_inline void
-f64_to_tv (f64 t, struct timeval *tv)
-{
-  tv->tv_sec = t;
-  tv->tv_usec = 1e6 * (t - tv->tv_sec);
-  while (tv->tv_usec >= 1000000)
-    {
-      tv->tv_usec -= 1000000;
-      tv->tv_sec += 1;
-    }
-}
-
-/* Sort timers so that timer soonest to expire is at end. */
-static int
-timer_compare (const void *_a, const void *_b)
-{
-  const timer_callback_t *a = _a;
-  const timer_callback_t *b = _b;
-  f64 dt = b->time - a->time;
-  return dt < 0 ? -1 : (dt > 0 ? +1 : 0);
-}
-
-static inline void
-sort_timers (timer_callback_t * timers)
-{
-  qsort (timers, vec_len (timers), sizeof (timers[0]), timer_compare);
-}
-
-#define TIMER_SIGNAL SIGALRM
-
-/* Don't bother set timer if time different is less than this value. */
-/* We would like to initialize this to 0.75 / (f64) HZ,
- * but HZ may not be a compile-time constant on some systems,
- * so instead we do the initialization before first use.
- */
-static f64 time_resolution;
-
-/* Interrupt handler.  Call functions for all expired timers.
-   Set time for next timer interrupt. */
-static void
-timer_interrupt (int signum)
-{
-  f64 now = unix_time_now ();
-  f64 dt;
-  timer_callback_t *t;
-
-  while (1)
-    {
-      if (vec_len (timers) <= 0)
-	return;
-
-      /* Consider last (earliest) timer in reverse sorted
-         vector of pending timers. */
-      t = vec_end (timers) - 1;
-
-      ASSERT (now >= 0 && isfinite (now));
-
-      /* Time difference between when timer goes off and now. */
-      dt = t->time - now;
-
-      /* If timer is within threshold of going off
-         call user's callback. */
-      if (dt <= time_resolution && isfinite (dt))
-	{
-	  _vec_len (timers) -= 1;
-	  (*t->func) (t->arg, -dt);
-	}
-      else
-	{
-	  /* Set timer for to go off in future. */
-	  struct itimerval itv;
-	  clib_memset (&itv, 0, sizeof (itv));
-	  f64_to_tv (dt, &itv.it_value);
-	  if (setitimer (ITIMER_REAL, &itv, 0) < 0)
-	    clib_unix_error ("sititmer");
-	  return;
-	}
-    }
-}
-
-void
-timer_block (sigset_t * save)
-{
-  sigset_t block_timer;
-
-  clib_memset (&block_timer, 0, sizeof (block_timer));
-  sigaddset (&block_timer, TIMER_SIGNAL);
-  sigprocmask (SIG_BLOCK, &block_timer, save);
-}
-
-void
-timer_unblock (sigset_t * save)
-{
-  sigprocmask (SIG_SETMASK, save, 0);
-}
-
-/* Arrange for function to be called some time,
-   roughly equal to dt seconds, in the future. */
-void
-timer_call (timer_func_t * func, any arg, f64 dt)
-{
-  timer_callback_t *t;
-  sigset_t save;
-
-  /* Install signal handler on first call. */
-  static word signal_installed = 0;
-
-  if (!signal_installed)
-    {
-      struct sigaction sa;
-
-      /* Initialize time_resolution before first call to timer_interrupt */
-      time_resolution = 0.75 / (f64) HZ;
-
-      clib_memset (&sa, 0, sizeof (sa));
-      sa.sa_handler = timer_interrupt;
-
-      if (sigaction (TIMER_SIGNAL, &sa, 0) < 0)
-	clib_panic ("sigaction");
-
-      signal_installed = 1;
-    }
-
-  timer_block (&save);
-
-  /* Add new timer. */
-  vec_add2 (timers, t, 1);
-
-  t->time = unix_time_now () + dt;
-  t->func = func;
-  t->arg = arg;
-
-  {
-    word reset_timer = vec_len (timers) == 1;
-
-    if (_vec_len (timers) > 1)
-      {
-	reset_timer += t->time < (t - 1)->time;
-	sort_timers (timers);
-      }
-
-    if (reset_timer)
-      timer_interrupt (TIMER_SIGNAL);
-  }
-
-  timer_unblock (&save);
-}
-
-#ifdef TEST
-
-#include <vppinfra/random.h>
-
-/* Compute average delay of function calls to foo.
-   If this is a small number over a lot of iterations we know
-   the code is working. */
-
-static f64 ave_delay = 0;
-static word ave_delay_count = 0;
-
-always_inline
-update (f64 delay)
-{
-  ave_delay += delay;
-  ave_delay_count += 1;
-}
-
-typedef struct
-{
-  f64 time_requested, time_called;
-} foo_t;
-
-static f64 foo_base_time = 0;
-static foo_t *foos = 0;
-
-void
-foo (any arg, f64 delay)
-{
-  foos[arg].time_called = unix_time_now () - foo_base_time;
-  update (delay);
-}
-
-typedef struct
-{
-  word count;
-  word limit;
-} bar_t;
-
-void
-bar (any arg, f64 delay)
-{
-  bar_t *b = (bar_t *) arg;
-
-  fformat (stdout, "bar %d delay %g\n", b->count++, delay);
-
-  update (delay);
-  if (b->count < b->limit)
-    timer_call (bar, arg, random_f64 ());
-}
-
-int
-main (int argc, char *argv[])
-{
-  word i, n = atoi (argv[1]);
-  word run_foo = argc > 2;
-bar_t b = { limit:10 };
-
-  if (run_foo)
-    {
-      f64 time_limit;
-
-      time_limit = atof (argv[2]);
-
-      vec_resize (foos, n);
-      for (i = 0; i < n; i++)
-	{
-	  foos[i].time_requested = time_limit * random_f64 ();
-	  foos[i].time_called = 1e100;
-	}
-
-      foo_base_time = unix_time_now ();
-      for (i = 0; i < n; i++)
-	timer_call (foo, i, foos[i].time_requested);
-    }
-  else
-    timer_call (bar, (any) & b, random_f64 ());
-
-  while (vec_len (timers) > 0)
-    os_sched_yield ();
-
-  if (vec_len (foos) > 0)
-    {
-      f64 min = 1e100, max = -min;
-      f64 ave = 0, rms = 0;
-
-      for (i = 0; i < n; i++)
-	{
-	  f64 dt = foos[i].time_requested - foos[i].time_called;
-	  if (dt < min)
-	    min = dt;
-	  if (dt > max)
-	    max = dt;
-	  ave += dt;
-	  rms += dt * dt;
-	}
-      ave /= n;
-      rms = sqrt (rms / n - ave * ave);
-      fformat (stdout, "error min %g max %g ave %g +- %g\n", min, max, ave,
-	       rms);
-    }
-
-  fformat (stdout, "%d function calls, ave. timer delay %g secs\n",
-	   ave_delay_count, ave_delay / ave_delay_count);
-
-  return 0;
-}
-#endif
-
-/*
- * fd.io coding-style-patch-verification: ON
- *
- * Local Variables:
- * eval: (c-set-style "gnu")
- * End:
- */
diff --git a/src/vppinfra/timer.h b/src/vppinfra/timer.h
deleted file mode 100644
index 764103f702d..00000000000
--- a/src/vppinfra/timer.h
+++ /dev/null
@@ -1,46 +0,0 @@
-/*
-  Copyright (c) 2001, 2002, 2003 Eliot Dresselhaus
-
-  Permission is hereby granted, free of charge, to any person obtaining
-  a copy of this software and associated documentation files (the
-  "Software"), to deal in the Software without restriction, including
-  without limitation the rights to use, copy, modify, merge, publish,
-  distribute, sublicense, and/or sell copies of the Software, and to
-  permit persons to whom the Software is furnished to do so, subject to
-  the following conditions:
-
-  The above copyright notice and this permission notice shall be
-  included in all copies or substantial portions of the Software.
-
-  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-*/
-
-#ifndef included_timer_h
-#define included_timer_h
-
-#include <signal.h>
-
-typedef void (timer_func_t) (any arg, f64 delay);
-
-/* Arrange for function to be called after time interval (in seconds) has elapsed. */
-extern void timer_call (timer_func_t * func, any arg, f64 time_interval);
-
-/* Block/unblock timer interrupts. */
-extern void timer_block (sigset_t * save);
-extern void timer_unblock (sigset_t * save);
-
-#endif /* included_timer_h */
-
-/*
- * fd.io coding-style-patch-verification: ON
- *
- * Local Variables:
- * eval: (c-set-style "gnu")
- * End:
- */