Initial revision
diff --git a/isisd/modified/thread.c b/isisd/modified/thread.c
new file mode 100644
index 0000000..af954b8
--- /dev/null
+++ b/isisd/modified/thread.c
@@ -0,0 +1,713 @@
+/* Thread management routine
+ * Copyright (C) 1998, 2000 Kunihiro Ishiguro <kunihiro@zebra.org>
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * GNU Zebra 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING. If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+/* #define DEBUG */
+
+#include <zebra.h>
+
+#include "thread.h"
+#include "memory.h"
+#include "log.h"
+
+/* Struct timeval's tv_usec one second value. */
+#define TIMER_SECOND_MICRO 1000000L
+
+struct timeval
+timeval_adjust (struct timeval a)
+{
+ while (a.tv_usec >= TIMER_SECOND_MICRO)
+ {
+ a.tv_usec -= TIMER_SECOND_MICRO;
+ a.tv_sec++;
+ }
+
+ while (a.tv_usec < 0)
+ {
+ a.tv_usec += TIMER_SECOND_MICRO;
+ a.tv_sec--;
+ }
+
+ if (a.tv_sec < 0)
+ {
+ a.tv_sec = 0;
+ a.tv_usec = 10;
+ }
+
+ if (a.tv_sec > TIMER_SECOND_MICRO)
+ a.tv_sec = TIMER_SECOND_MICRO;
+
+ return a;
+}
+
+static struct timeval
+timeval_subtract (struct timeval a, struct timeval b)
+{
+ struct timeval ret;
+
+ ret.tv_usec = a.tv_usec - b.tv_usec;
+ ret.tv_sec = a.tv_sec - b.tv_sec;
+
+ return timeval_adjust (ret);
+}
+
+static int
+timeval_cmp (struct timeval a, struct timeval b)
+{
+ return (a.tv_sec == b.tv_sec
+ ? a.tv_usec - b.tv_usec : a.tv_sec - b.tv_sec);
+}
+
+static unsigned long
+timeval_elapsed (struct timeval a, struct timeval b)
+{
+ return (((a.tv_sec - b.tv_sec) * TIMER_SECOND_MICRO)
+ + (a.tv_usec - b.tv_usec));
+}
+
+/* List allocation and head/tail print out. */
+static void
+thread_list_debug (struct thread_list *list)
+{
+ printf ("count [%d] head [%p] tail [%p]\n",
+ list->count, list->head, list->tail);
+}
+
+/* Debug print for thread_master. */
+void
+thread_master_debug (struct thread_master *m)
+{
+ printf ("-----------\n");
+ printf ("readlist : ");
+ thread_list_debug (&m->read);
+ printf ("writelist : ");
+ thread_list_debug (&m->write);
+ printf ("timerlist : ");
+ thread_list_debug (&m->timer);
+ printf ("eventlist : ");
+ thread_list_debug (&m->event);
+ printf ("unuselist : ");
+ thread_list_debug (&m->unuse);
+ printf ("total alloc: [%ld]\n", m->alloc);
+ printf ("-----------\n");
+}
+
+/* Allocate new thread master. */
+struct thread_master *
+thread_master_create ()
+{
+ return (struct thread_master *) XCALLOC (MTYPE_THREAD_MASTER,
+ sizeof (struct thread_master));
+}
+
+/* Add a new thread to the list. */
+static void
+thread_list_add (struct thread_list *list, struct thread *thread)
+{
+ thread->next = NULL;
+ thread->prev = list->tail;
+ if (list->tail)
+ list->tail->next = thread;
+ else
+ list->head = thread;
+ list->tail = thread;
+ list->count++;
+}
+
+/* Add a new thread just before the point. */
+static void
+thread_list_add_before (struct thread_list *list,
+ struct thread *point,
+ struct thread *thread)
+{
+ thread->next = point;
+ thread->prev = point->prev;
+ if (point->prev)
+ point->prev->next = thread;
+ else
+ list->head = thread;
+ point->prev = thread;
+ list->count++;
+}
+
+/* Delete a thread from the list. */
+static struct thread *
+thread_list_delete (struct thread_list *list, struct thread *thread)
+{
+ if (thread->next)
+ thread->next->prev = thread->prev;
+ else
+ list->tail = thread->prev;
+ if (thread->prev)
+ thread->prev->next = thread->next;
+ else
+ list->head = thread->next;
+ thread->next = thread->prev = NULL;
+ list->count--;
+ return thread;
+}
+
+/* Move thread to unuse list. */
+static void
+thread_add_unuse (struct thread_master *m, struct thread *thread)
+{
+ assert (m != NULL);
+ assert (thread->next == NULL);
+ assert (thread->prev == NULL);
+ assert (thread->type == THREAD_UNUSED);
+ thread_list_add (&m->unuse, thread);
+}
+
+/* Free all unused thread. */
+static void
+thread_list_free (struct thread_master *m, struct thread_list *list)
+{
+ struct thread *t;
+ struct thread *next;
+
+ for (t = list->head; t; t = next)
+ {
+ next = t->next;
+ XFREE (MTYPE_THREAD, t);
+ list->count--;
+ m->alloc--;
+ }
+}
+
+/* Stop thread scheduler. */
+void
+thread_master_free (struct thread_master *m)
+{
+ thread_list_free (m, &m->read);
+ thread_list_free (m, &m->write);
+ thread_list_free (m, &m->timer);
+ thread_list_free (m, &m->event);
+ thread_list_free (m, &m->ready);
+ thread_list_free (m, &m->unuse);
+
+ XFREE (MTYPE_THREAD_MASTER, m);
+}
+
+/* Delete top of the list and return it. */
+static struct thread *
+thread_trim_head (struct thread_list *list)
+{
+ if (list->head)
+ return thread_list_delete (list, list->head);
+ return NULL;
+}
+
+/* Thread list is empty or not. */
+int
+thread_empty (struct thread_list *list)
+{
+ return list->head ? 0 : 1;
+}
+
+/* Return remain time in second. */
+unsigned long
+thread_timer_remain_second (struct thread *thread)
+{
+ struct timeval timer_now;
+
+ gettimeofday (&timer_now, NULL);
+
+ if (thread->u.sands.tv_sec - timer_now.tv_sec > 0)
+ return thread->u.sands.tv_sec - timer_now.tv_sec;
+ else
+ return 0;
+}
+
+/* Get new thread. */
+static struct thread *
+thread_get (struct thread_master *m, u_char type,
+ int (*func) (struct thread *), void *arg)
+{
+ struct thread *thread;
+
+ if (m->unuse.head)
+ thread = thread_trim_head (&m->unuse);
+ else
+ {
+ thread = XCALLOC (MTYPE_THREAD, sizeof (struct thread));
+ m->alloc++;
+ }
+ thread->type = type;
+ thread->master = m;
+ thread->func = func;
+ thread->arg = arg;
+
+ return thread;
+}
+
+/* Add new read thread. */
+struct thread *
+thread_add_read (struct thread_master *m,
+ int (*func) (struct thread *), void *arg, int fd)
+{
+ struct thread *thread;
+
+ assert (m != NULL);
+
+ if (FD_ISSET (fd, &m->readfd))
+ {
+ zlog (NULL, LOG_WARNING, "There is already read fd [%d]", fd);
+ return NULL;
+ }
+
+ thread = thread_get (m, THREAD_READ, func, arg);
+ FD_SET (fd, &m->readfd);
+ thread->u.fd = fd;
+ thread_list_add (&m->read, thread);
+
+ return thread;
+}
+
+/* Add new write thread. */
+struct thread *
+thread_add_write (struct thread_master *m,
+ int (*func) (struct thread *), void *arg, int fd)
+{
+ struct thread *thread;
+
+ assert (m != NULL);
+
+ if (FD_ISSET (fd, &m->writefd))
+ {
+ zlog (NULL, LOG_WARNING, "There is already write fd [%d]", fd);
+ return NULL;
+ }
+
+ thread = thread_get (m, THREAD_WRITE, func, arg);
+ FD_SET (fd, &m->writefd);
+ thread->u.fd = fd;
+ thread_list_add (&m->write, thread);
+
+ return thread;
+}
+
+/* Add timer event thread. */
+struct thread *
+thread_add_timer (struct thread_master *m,
+ int (*func) (struct thread *), void *arg, long timer)
+{
+ struct timeval timer_now;
+ struct thread *thread;
+#ifndef TIMER_NO_SORT
+ struct thread *tt;
+#endif /* TIMER_NO_SORT */
+
+ assert (m != NULL);
+
+ thread = thread_get (m, THREAD_TIMER, func, arg);
+
+ /* Do we need jitter here? */
+ gettimeofday (&timer_now, NULL);
+ timer_now.tv_sec += timer;
+ thread->u.sands = timer_now;
+
+ /* Sort by timeval. */
+#ifdef TIMER_NO_SORT
+ thread_list_add (&m->timer, thread);
+#else
+ for (tt = m->timer.head; tt; tt = tt->next)
+ if (timeval_cmp (thread->u.sands, tt->u.sands) <= 0)
+ break;
+
+ if (tt)
+ thread_list_add_before (&m->timer, tt, thread);
+ else
+ thread_list_add (&m->timer, thread);
+#endif /* TIMER_NO_SORT */
+
+ return thread;
+}
+
+/* Add timer event thread with "millisecond" resolution */
+struct thread *
+thread_add_timer_msec (struct thread_master *m,
+ int (*func)(struct thread *),
+ void *arg, long timer)
+{
+ struct timeval timer_now;
+ struct thread *thread;
+#ifndef TIMER_NO_SORT
+ struct thread *tt;
+#endif /* TIMER_NO_SORT */
+
+ assert (m != NULL);
+
+ thread = thread_get (m, THREAD_TIMER, func, arg);
+
+ timer = 1000*timer; /* milli -> micro */
+
+ gettimeofday (&timer_now, NULL);
+ timer_now.tv_sec += timer / TIMER_SECOND_MICRO;
+ timer_now.tv_usec += (timer % TIMER_SECOND_MICRO);
+ thread->u.sands = timer_now;
+
+
+ /* Sort by timeval. */
+#ifdef TIMER_NO_SORT
+ thread_list_add (&m->timer, thread);
+#else
+ for (tt = m->timer.head; tt; tt = tt->next)
+ if (timeval_cmp (thread->u.sands, tt->u.sands) <= 0)
+ break;
+
+ if (tt)
+ thread_list_add_before (&m->timer, tt, thread);
+ else
+ thread_list_add (&m->timer, thread);
+#endif /* TIMER_NO_SORT */
+
+ return thread;
+}
+
+
+/* Add simple event thread. */
+struct thread *
+thread_add_event (struct thread_master *m,
+ int (*func) (struct thread *), void *arg, int val)
+{
+ struct thread *thread;
+
+ assert (m != NULL);
+
+ thread = thread_get (m, THREAD_EVENT, func, arg);
+ thread->u.val = val;
+ thread_list_add (&m->event, thread);
+
+ return thread;
+}
+
+/* Cancel thread from scheduler. */
+void
+thread_cancel (struct thread *thread)
+{
+ switch (thread->type)
+ {
+ case THREAD_READ:
+ assert (FD_ISSET (thread->u.fd, &thread->master->readfd));
+ FD_CLR (thread->u.fd, &thread->master->readfd);
+ thread_list_delete (&thread->master->read, thread);
+ break;
+ case THREAD_WRITE:
+ assert (FD_ISSET (thread->u.fd, &thread->master->writefd));
+ FD_CLR (thread->u.fd, &thread->master->writefd);
+ thread_list_delete (&thread->master->write, thread);
+ break;
+ case THREAD_TIMER:
+ thread_list_delete (&thread->master->timer, thread);
+ break;
+ case THREAD_EVENT:
+ thread_list_delete (&thread->master->event, thread);
+ break;
+ case THREAD_READY:
+ thread_list_delete (&thread->master->ready, thread);
+ break;
+ case THREAD_UNUSED:
+ thread_list_delete (&thread->master->unuse, thread);
+ break;
+ default:
+ break;
+ }
+ thread->type = THREAD_UNUSED;
+ thread_add_unuse (thread->master, thread);
+}
+
+/* Delete all events which has argument value arg. */
+void
+thread_cancel_event (struct thread_master *m, void *arg)
+{
+ struct thread *thread;
+
+ thread = m->event.head;
+ while (thread)
+ {
+ struct thread *t;
+
+ t = thread;
+ thread = t->next;
+
+ if (t->arg == arg)
+ {
+ thread_list_delete (&m->event, t);
+ t->type = THREAD_UNUSED;
+ thread_add_unuse (m, t);
+ }
+ }
+}
+
+#ifdef TIMER_NO_SORT
+struct timeval *
+thread_timer_wait (struct thread_master *m, struct timeval *timer_val)
+{
+ struct timeval timer_now;
+ struct timeval timer_min;
+ struct timeval *timer_wait;
+
+ gettimeofday (&timer_now, NULL);
+
+ timer_wait = NULL;
+ for (thread = m->timer.head; thread; thread = thread->next)
+ {
+ if (! timer_wait)
+ timer_wait = &thread->u.sands;
+ else if (timeval_cmp (thread->u.sands, *timer_wait) < 0)
+ timer_wait = &thread->u.sands;
+ }
+
+ if (m->timer.head)
+ {
+ timer_min = *timer_wait;
+ timer_min = timeval_subtract (timer_min, timer_now);
+ if (timer_min.tv_sec < 0)
+ {
+ timer_min.tv_sec = 0;
+ timer_min.tv_usec = 10;
+ }
+ timer_wait = &timer_min;
+ }
+ else
+ timer_wait = NULL;
+
+ if (timer_wait)
+ {
+ *timer_val = timer_wait;
+ return timer_val;
+ }
+ return NULL;
+}
+#else /* ! TIMER_NO_SORT */
+struct timeval *
+thread_timer_wait (struct thread_master *m, struct timeval *timer_val)
+{
+ struct timeval timer_now;
+ struct timeval timer_min;
+
+ if (m->timer.head)
+ {
+ gettimeofday (&timer_now, NULL);
+ timer_min = m->timer.head->u.sands;
+ timer_min = timeval_subtract (timer_min, timer_now);
+ if (timer_min.tv_sec < 0)
+ {
+ timer_min.tv_sec = 0;
+ timer_min.tv_usec = 10;
+ }
+ *timer_val = timer_min;
+ return timer_val;
+ }
+ return NULL;
+}
+#endif /* TIMER_NO_SORT */
+
+struct thread *
+thread_run (struct thread_master *m, struct thread *thread,
+ struct thread *fetch)
+{
+ *fetch = *thread;
+ thread->type = THREAD_UNUSED;
+ thread_add_unuse (m, thread);
+ return fetch;
+}
+
+int
+thread_process_fd (struct thread_master *m, struct thread_list *list,
+ fd_set *fdset, fd_set *mfdset)
+{
+ struct thread *thread;
+ struct thread *next;
+ int ready = 0;
+
+ for (thread = list->head; thread; thread = next)
+ {
+ next = thread->next;
+
+ if (FD_ISSET (THREAD_FD (thread), fdset))
+ {
+ assert (FD_ISSET (THREAD_FD (thread), mfdset));
+ FD_CLR(THREAD_FD (thread), mfdset);
+ thread_list_delete (list, thread);
+ thread_list_add (&m->ready, thread);
+ thread->type = THREAD_READY;
+ ready++;
+ }
+ }
+ return ready;
+}
+
+/* Fetch next ready thread. */
+struct thread *
+thread_fetch (struct thread_master *m, struct thread *fetch)
+{
+ int num;
+ int ready;
+ struct thread *thread;
+ fd_set readfd;
+ fd_set writefd;
+ fd_set exceptfd;
+ struct timeval timer_now;
+ struct timeval timer_val;
+ struct timeval *timer_wait;
+ struct timeval timer_nowait;
+
+ timer_nowait.tv_sec = 0;
+ timer_nowait.tv_usec = 0;
+
+ while (1)
+ {
+ /* Normal event is the highest priority. */
+ if ((thread = thread_trim_head (&m->event)) != NULL)
+ return thread_run (m, thread, fetch);
+
+ /* Execute timer. */
+ gettimeofday (&timer_now, NULL);
+
+ for (thread = m->timer.head; thread; thread = thread->next)
+ if (timeval_cmp (timer_now, thread->u.sands) >= 0)
+ {
+ thread_list_delete (&m->timer, thread);
+ return thread_run (m, thread, fetch);
+ }
+
+ /* If there are any ready threads, process top of them. */
+ if ((thread = thread_trim_head (&m->ready)) != NULL)
+ return thread_run (m, thread, fetch);
+
+ /* Structure copy. */
+ readfd = m->readfd;
+ writefd = m->writefd;
+ exceptfd = m->exceptfd;
+
+ /* Calculate select wait timer. */
+ timer_wait = thread_timer_wait (m, &timer_val);
+
+ num = select (FD_SETSIZE, &readfd, &writefd, &exceptfd, timer_wait);
+
+ if (num == 0)
+ continue;
+
+ if (num < 0)
+ {
+ if (errno == EINTR)
+ continue;
+
+ zlog_warn ("select() error: %s", strerror (errno));
+ return NULL;
+ }
+
+ /* Normal priority read thead. */
+ ready = thread_process_fd (m, &m->read, &readfd, &m->readfd);
+
+ /* Write thead. */
+ ready = thread_process_fd (m, &m->write, &writefd, &m->writefd);
+
+ if ((thread = thread_trim_head (&m->ready)) != NULL)
+ return thread_run (m, thread, fetch);
+ }
+}
+
+static unsigned long
+thread_consumed_time (RUSAGE_T *now, RUSAGE_T *start)
+{
+ unsigned long thread_time;
+
+#ifdef HAVE_RUSAGE
+ /* This is 'user + sys' time. */
+ thread_time = timeval_elapsed (now->ru_utime, start->ru_utime);
+ thread_time += timeval_elapsed (now->ru_stime, start->ru_stime);
+#else
+ /* When rusage is not available, simple elapsed time is used. */
+ thread_time = timeval_elapsed (*now, *start);
+#endif /* HAVE_RUSAGE */
+
+ return thread_time;
+}
+
+/* We should aim to yield after THREAD_YIELD_TIME_SLOT
+ milliseconds. */
+int
+thread_should_yield (struct thread *thread)
+{
+ RUSAGE_T ru;
+
+ GETRUSAGE (&ru);
+
+ if (thread_consumed_time (&ru, &thread->ru) > THREAD_YIELD_TIME_SLOT)
+ return 1;
+ else
+ return 0;
+}
+
+/* We check thread consumed time. If the system has getrusage, we'll
+ use that to get indepth stats on the performance of the thread. If
+ not - we'll use gettimeofday for some guestimation. */
+void
+thread_call (struct thread *thread)
+{
+ unsigned long thread_time;
+ RUSAGE_T ru;
+
+ GETRUSAGE (&thread->ru);
+
+ (*thread->func) (thread);
+
+ GETRUSAGE (&ru);
+
+ thread_time = thread_consumed_time (&ru, &thread->ru);
+
+#ifdef THREAD_CONSUMED_TIME_CHECK
+ if (thread_time > 200000L)
+ {
+ /*
+ * We have a CPU Hog on our hands.
+ * Whinge about it now, so we're aware this is yet another task
+ * to fix.
+ */
+ zlog_err ("CPU HOG task %lx ran for %ldms",
+ /* FIXME: report the name of the function somehow */
+ (unsigned long) thread->func,
+ thread_time / 1000L);
+ }
+#endif /* THREAD_CONSUMED_TIME_CHECK */
+}
+
+/* Execute thread */
+struct thread *
+thread_execute (struct thread_master *m,
+ int (*func)(struct thread *),
+ void *arg,
+ int val)
+{
+ struct thread dummy;
+
+ memset (&dummy, 0, sizeof (struct thread));
+
+ dummy.type = THREAD_EVENT;
+ dummy.master = NULL;
+ dummy.func = func;
+ dummy.arg = arg;
+ dummy.u.val = val;
+ thread_call (&dummy);
+
+ return NULL;
+}