summaryrefslogtreecommitdiff
path: root/pjlib/src/pj/timer.c
diff options
context:
space:
mode:
Diffstat (limited to 'pjlib/src/pj/timer.c')
-rw-r--r--pjlib/src/pj/timer.c610
1 files changed, 610 insertions, 0 deletions
diff --git a/pjlib/src/pj/timer.c b/pjlib/src/pj/timer.c
new file mode 100644
index 0000000..e78cba3
--- /dev/null
+++ b/pjlib/src/pj/timer.c
@@ -0,0 +1,610 @@
+/* $Id: timer.c 4154 2012-06-05 10:41:17Z bennylp $ */
+/*
+ * The PJLIB's timer heap is based (or more correctly, copied and modied)
+ * from ACE library by Douglas C. Schmidt. ACE is an excellent OO framework
+ * that implements many core patterns for concurrent communication software.
+ * If you're looking for C++ alternative of PJLIB, then ACE is your best
+ * solution.
+ *
+ * You may use this file according to ACE open source terms or PJLIB open
+ * source terms. You can find the fine ACE library at:
+ * http://www.cs.wustl.edu/~schmidt/ACE.html
+ *
+ * ACE is Copyright (C)1993-2006 Douglas C. Schmidt <d.schmidt@vanderbilt.edu>
+ *
+ * GNU Public License:
+ * This program 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 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <pj/timer.h>
+#include <pj/pool.h>
+#include <pj/os.h>
+#include <pj/string.h>
+#include <pj/assert.h>
+#include <pj/errno.h>
+#include <pj/lock.h>
+#include <pj/log.h>
+
+#define THIS_FILE "timer.c"
+
+#define HEAP_PARENT(X) (X == 0 ? 0 : (((X) - 1) / 2))
+#define HEAP_LEFT(X) (((X)+(X))+1)
+
+
+#define DEFAULT_MAX_TIMED_OUT_PER_POLL (64)
+
+
+/**
+ * The implementation of timer heap.
+ */
+struct pj_timer_heap_t
+{
+ /** Pool from which the timer heap resize will get the storage from */
+ pj_pool_t *pool;
+
+ /** Maximum size of the heap. */
+ pj_size_t max_size;
+
+ /** Current size of the heap. */
+ pj_size_t cur_size;
+
+ /** Max timed out entries to process per poll. */
+ unsigned max_entries_per_poll;
+
+ /** Lock object. */
+ pj_lock_t *lock;
+
+ /** Autodelete lock. */
+ pj_bool_t auto_delete_lock;
+
+ /**
+ * Current contents of the Heap, which is organized as a "heap" of
+ * pj_timer_entry *'s. In this context, a heap is a "partially
+ * ordered, almost complete" binary tree, which is stored in an
+ * array.
+ */
+ pj_timer_entry **heap;
+
+ /**
+ * An array of "pointers" that allows each pj_timer_entry in the
+ * <heap_> to be located in O(1) time. Basically, <timer_id_[i]>
+ * contains the slot in the <heap_> array where an pj_timer_entry
+ * with timer id <i> resides. Thus, the timer id passed back from
+ * <schedule_entry> is really an slot into the <timer_ids> array. The
+ * <timer_ids_> array serves two purposes: negative values are
+ * treated as "pointers" for the <freelist_>, whereas positive
+ * values are treated as "pointers" into the <heap_> array.
+ */
+ pj_timer_id_t *timer_ids;
+
+ /**
+ * "Pointer" to the first element in the freelist contained within
+ * the <timer_ids_> array, which is organized as a stack.
+ */
+ pj_timer_id_t timer_ids_freelist;
+
+ /** Callback to be called when a timer expires. */
+ pj_timer_heap_callback *callback;
+
+};
+
+
+
+PJ_INLINE(void) lock_timer_heap( pj_timer_heap_t *ht )
+{
+ if (ht->lock) {
+ pj_lock_acquire(ht->lock);
+ }
+}
+
+PJ_INLINE(void) unlock_timer_heap( pj_timer_heap_t *ht )
+{
+ if (ht->lock) {
+ pj_lock_release(ht->lock);
+ }
+}
+
+
+static void copy_node( pj_timer_heap_t *ht, int slot, pj_timer_entry *moved_node )
+{
+ PJ_CHECK_STACK();
+
+ // Insert <moved_node> into its new location in the heap.
+ ht->heap[slot] = moved_node;
+
+ // Update the corresponding slot in the parallel <timer_ids_> array.
+ ht->timer_ids[moved_node->_timer_id] = slot;
+}
+
+static pj_timer_id_t pop_freelist( pj_timer_heap_t *ht )
+{
+ // We need to truncate this to <int> for backwards compatibility.
+ pj_timer_id_t new_id = ht->timer_ids_freelist;
+
+ PJ_CHECK_STACK();
+
+ // The freelist values in the <timer_ids_> are negative, so we need
+ // to negate them to get the next freelist "pointer."
+ ht->timer_ids_freelist =
+ -ht->timer_ids[ht->timer_ids_freelist];
+
+ return new_id;
+
+}
+
+static void push_freelist (pj_timer_heap_t *ht, pj_timer_id_t old_id)
+{
+ PJ_CHECK_STACK();
+
+ // The freelist values in the <timer_ids_> are negative, so we need
+ // to negate them to get the next freelist "pointer."
+ ht->timer_ids[old_id] = -ht->timer_ids_freelist;
+ ht->timer_ids_freelist = old_id;
+}
+
+
+static void reheap_down(pj_timer_heap_t *ht, pj_timer_entry *moved_node,
+ size_t slot, size_t child)
+{
+ PJ_CHECK_STACK();
+
+ // Restore the heap property after a deletion.
+
+ while (child < ht->cur_size)
+ {
+ // Choose the smaller of the two children.
+ if (child + 1 < ht->cur_size
+ && PJ_TIME_VAL_LT(ht->heap[child + 1]->_timer_value, ht->heap[child]->_timer_value))
+ child++;
+
+ // Perform a <copy> if the child has a larger timeout value than
+ // the <moved_node>.
+ if (PJ_TIME_VAL_LT(ht->heap[child]->_timer_value, moved_node->_timer_value))
+ {
+ copy_node( ht, slot, ht->heap[child]);
+ slot = child;
+ child = HEAP_LEFT(child);
+ }
+ else
+ // We've found our location in the heap.
+ break;
+ }
+
+ copy_node( ht, slot, moved_node);
+}
+
+static void reheap_up( pj_timer_heap_t *ht, pj_timer_entry *moved_node,
+ size_t slot, size_t parent)
+{
+ // Restore the heap property after an insertion.
+
+ while (slot > 0)
+ {
+ // If the parent node is greater than the <moved_node> we need
+ // to copy it down.
+ if (PJ_TIME_VAL_LT(moved_node->_timer_value, ht->heap[parent]->_timer_value))
+ {
+ copy_node(ht, slot, ht->heap[parent]);
+ slot = parent;
+ parent = HEAP_PARENT(slot);
+ }
+ else
+ break;
+ }
+
+ // Insert the new node into its proper resting place in the heap and
+ // update the corresponding slot in the parallel <timer_ids> array.
+ copy_node(ht, slot, moved_node);
+}
+
+
+static pj_timer_entry * remove_node( pj_timer_heap_t *ht, size_t slot)
+{
+ pj_timer_entry *removed_node = ht->heap[slot];
+
+ // Return this timer id to the freelist.
+ push_freelist( ht, removed_node->_timer_id );
+
+ // Decrement the size of the heap by one since we're removing the
+ // "slot"th node.
+ ht->cur_size--;
+
+ // Set the ID
+ removed_node->_timer_id = -1;
+
+ // Only try to reheapify if we're not deleting the last entry.
+
+ if (slot < ht->cur_size)
+ {
+ int parent;
+ pj_timer_entry *moved_node = ht->heap[ht->cur_size];
+
+ // Move the end node to the location being removed and update
+ // the corresponding slot in the parallel <timer_ids> array.
+ copy_node( ht, slot, moved_node);
+
+ // If the <moved_node->time_value_> is great than or equal its
+ // parent it needs be moved down the heap.
+ parent = HEAP_PARENT (slot);
+
+ if (PJ_TIME_VAL_GTE(moved_node->_timer_value, ht->heap[parent]->_timer_value))
+ reheap_down( ht, moved_node, slot, HEAP_LEFT(slot));
+ else
+ reheap_up( ht, moved_node, slot, parent);
+ }
+
+ return removed_node;
+}
+
+static void grow_heap(pj_timer_heap_t *ht)
+{
+ // All the containers will double in size from max_size_
+ size_t new_size = ht->max_size * 2;
+ pj_timer_id_t *new_timer_ids;
+ pj_size_t i;
+
+ // First grow the heap itself.
+
+ pj_timer_entry **new_heap = 0;
+
+ new_heap = (pj_timer_entry**)
+ pj_pool_alloc(ht->pool, sizeof(pj_timer_entry*) * new_size);
+ memcpy(new_heap, ht->heap, ht->max_size * sizeof(pj_timer_entry*));
+ //delete [] this->heap_;
+ ht->heap = new_heap;
+
+ // Grow the array of timer ids.
+
+ new_timer_ids = 0;
+ new_timer_ids = (pj_timer_id_t*)
+ pj_pool_alloc(ht->pool, new_size * sizeof(pj_timer_id_t));
+
+ memcpy( new_timer_ids, ht->timer_ids, ht->max_size * sizeof(pj_timer_id_t));
+
+ //delete [] timer_ids_;
+ ht->timer_ids = new_timer_ids;
+
+ // And add the new elements to the end of the "freelist".
+ for (i = ht->max_size; i < new_size; i++)
+ ht->timer_ids[i] = -((pj_timer_id_t) (i + 1));
+
+ ht->max_size = new_size;
+}
+
+static void insert_node(pj_timer_heap_t *ht, pj_timer_entry *new_node)
+{
+ if (ht->cur_size + 2 >= ht->max_size)
+ grow_heap(ht);
+
+ reheap_up( ht, new_node, ht->cur_size, HEAP_PARENT(ht->cur_size));
+ ht->cur_size++;
+}
+
+
+static pj_status_t schedule_entry( pj_timer_heap_t *ht,
+ pj_timer_entry *entry,
+ const pj_time_val *future_time )
+{
+ if (ht->cur_size < ht->max_size)
+ {
+ // Obtain the next unique sequence number.
+ // Set the entry
+ entry->_timer_id = pop_freelist(ht);
+ entry->_timer_value = *future_time;
+ insert_node( ht, entry);
+ return 0;
+ }
+ else
+ return -1;
+}
+
+
+static int cancel( pj_timer_heap_t *ht,
+ pj_timer_entry *entry,
+ int dont_call)
+{
+ long timer_node_slot;
+
+ PJ_CHECK_STACK();
+
+ // Check to see if the timer_id is out of range
+ if (entry->_timer_id < 0 || (pj_size_t)entry->_timer_id > ht->max_size)
+ return 0;
+
+ timer_node_slot = ht->timer_ids[entry->_timer_id];
+
+ if (timer_node_slot < 0) // Check to see if timer_id is still valid.
+ return 0;
+
+ if (entry != ht->heap[timer_node_slot])
+ {
+ pj_assert(entry == ht->heap[timer_node_slot]);
+ return 0;
+ }
+ else
+ {
+ remove_node( ht, timer_node_slot);
+
+ if (dont_call == 0)
+ // Call the close hook.
+ (*ht->callback)(ht, entry);
+ return 1;
+ }
+}
+
+
+/*
+ * Calculate memory size required to create a timer heap.
+ */
+PJ_DEF(pj_size_t) pj_timer_heap_mem_size(pj_size_t count)
+{
+ return /* size of the timer heap itself: */
+ sizeof(pj_timer_heap_t) +
+ /* size of each entry: */
+ (count+2) * (sizeof(pj_timer_entry*)+sizeof(pj_timer_id_t)) +
+ /* lock, pool etc: */
+ 132;
+}
+
+/*
+ * Create a new timer heap.
+ */
+PJ_DEF(pj_status_t) pj_timer_heap_create( pj_pool_t *pool,
+ pj_size_t size,
+ pj_timer_heap_t **p_heap)
+{
+ pj_timer_heap_t *ht;
+ pj_size_t i;
+
+ PJ_ASSERT_RETURN(pool && p_heap, PJ_EINVAL);
+
+ *p_heap = NULL;
+
+ /* Magic? */
+ size += 2;
+
+ /* Allocate timer heap data structure from the pool */
+ ht = PJ_POOL_ALLOC_T(pool, pj_timer_heap_t);
+ if (!ht)
+ return PJ_ENOMEM;
+
+ /* Initialize timer heap sizes */
+ ht->max_size = size;
+ ht->cur_size = 0;
+ ht->max_entries_per_poll = DEFAULT_MAX_TIMED_OUT_PER_POLL;
+ ht->timer_ids_freelist = 1;
+ ht->pool = pool;
+
+ /* Lock. */
+ ht->lock = NULL;
+ ht->auto_delete_lock = 0;
+
+ // Create the heap array.
+ ht->heap = (pj_timer_entry**)
+ pj_pool_alloc(pool, sizeof(pj_timer_entry*) * size);
+ if (!ht->heap)
+ return PJ_ENOMEM;
+
+ // Create the parallel
+ ht->timer_ids = (pj_timer_id_t *)
+ pj_pool_alloc( pool, sizeof(pj_timer_id_t) * size);
+ if (!ht->timer_ids)
+ return PJ_ENOMEM;
+
+ // Initialize the "freelist," which uses negative values to
+ // distinguish freelist elements from "pointers" into the <heap_>
+ // array.
+ for (i=0; i<size; ++i)
+ ht->timer_ids[i] = -((pj_timer_id_t) (i + 1));
+
+ *p_heap = ht;
+ return PJ_SUCCESS;
+}
+
+PJ_DEF(void) pj_timer_heap_destroy( pj_timer_heap_t *ht )
+{
+ if (ht->lock && ht->auto_delete_lock) {
+ pj_lock_destroy(ht->lock);
+ ht->lock = NULL;
+ }
+}
+
+PJ_DEF(void) pj_timer_heap_set_lock( pj_timer_heap_t *ht,
+ pj_lock_t *lock,
+ pj_bool_t auto_del )
+{
+ if (ht->lock && ht->auto_delete_lock)
+ pj_lock_destroy(ht->lock);
+
+ ht->lock = lock;
+ ht->auto_delete_lock = auto_del;
+}
+
+
+PJ_DEF(unsigned) pj_timer_heap_set_max_timed_out_per_poll(pj_timer_heap_t *ht,
+ unsigned count )
+{
+ unsigned old_count = ht->max_entries_per_poll;
+ ht->max_entries_per_poll = count;
+ return old_count;
+}
+
+PJ_DEF(pj_timer_entry*) pj_timer_entry_init( pj_timer_entry *entry,
+ int id,
+ void *user_data,
+ pj_timer_heap_callback *cb )
+{
+ pj_assert(entry && cb);
+
+ entry->_timer_id = -1;
+ entry->id = id;
+ entry->user_data = user_data;
+ entry->cb = cb;
+
+ return entry;
+}
+
+#if PJ_TIMER_DEBUG
+PJ_DEF(pj_status_t) pj_timer_heap_schedule_dbg( pj_timer_heap_t *ht,
+ pj_timer_entry *entry,
+ const pj_time_val *delay,
+ const char *src_file,
+ int src_line)
+#else
+PJ_DEF(pj_status_t) pj_timer_heap_schedule( pj_timer_heap_t *ht,
+ pj_timer_entry *entry,
+ const pj_time_val *delay)
+#endif
+{
+ pj_status_t status;
+ pj_time_val expires;
+
+ PJ_ASSERT_RETURN(ht && entry && delay, PJ_EINVAL);
+ PJ_ASSERT_RETURN(entry->cb != NULL, PJ_EINVAL);
+
+ /* Prevent same entry from being scheduled more than once */
+ PJ_ASSERT_RETURN(entry->_timer_id < 1, PJ_EINVALIDOP);
+
+#if PJ_TIMER_DEBUG
+ entry->src_file = src_file;
+ entry->src_line = src_line;
+#endif
+ pj_gettickcount(&expires);
+ PJ_TIME_VAL_ADD(expires, *delay);
+
+ lock_timer_heap(ht);
+ status = schedule_entry(ht, entry, &expires);
+ unlock_timer_heap(ht);
+
+ return status;
+}
+
+PJ_DEF(int) pj_timer_heap_cancel( pj_timer_heap_t *ht,
+ pj_timer_entry *entry)
+{
+ int count;
+
+ PJ_ASSERT_RETURN(ht && entry, PJ_EINVAL);
+
+ lock_timer_heap(ht);
+ count = cancel(ht, entry, 1);
+ unlock_timer_heap(ht);
+
+ return count;
+}
+
+PJ_DEF(unsigned) pj_timer_heap_poll( pj_timer_heap_t *ht,
+ pj_time_val *next_delay )
+{
+ pj_time_val now;
+ unsigned count;
+
+ PJ_ASSERT_RETURN(ht, 0);
+
+ if (!ht->cur_size && next_delay) {
+ next_delay->sec = next_delay->msec = PJ_MAXINT32;
+ return 0;
+ }
+
+ count = 0;
+ pj_gettickcount(&now);
+
+ lock_timer_heap(ht);
+ while ( ht->cur_size &&
+ PJ_TIME_VAL_LTE(ht->heap[0]->_timer_value, now) &&
+ count < ht->max_entries_per_poll )
+ {
+ pj_timer_entry *node = remove_node(ht, 0);
+ ++count;
+
+ unlock_timer_heap(ht);
+ if (node->cb)
+ (*node->cb)(ht, node);
+ lock_timer_heap(ht);
+ }
+ if (ht->cur_size && next_delay) {
+ *next_delay = ht->heap[0]->_timer_value;
+ PJ_TIME_VAL_SUB(*next_delay, now);
+ if (next_delay->sec < 0 || next_delay->msec < 0)
+ next_delay->sec = next_delay->msec = 0;
+ } else if (next_delay) {
+ next_delay->sec = next_delay->msec = PJ_MAXINT32;
+ }
+ unlock_timer_heap(ht);
+
+ return count;
+}
+
+PJ_DEF(pj_size_t) pj_timer_heap_count( pj_timer_heap_t *ht )
+{
+ PJ_ASSERT_RETURN(ht, 0);
+
+ return ht->cur_size;
+}
+
+PJ_DEF(pj_status_t) pj_timer_heap_earliest_time( pj_timer_heap_t * ht,
+ pj_time_val *timeval)
+{
+ pj_assert(ht->cur_size != 0);
+ if (ht->cur_size == 0)
+ return PJ_ENOTFOUND;
+
+ lock_timer_heap(ht);
+ *timeval = ht->heap[0]->_timer_value;
+ unlock_timer_heap(ht);
+
+ return PJ_SUCCESS;
+}
+
+#if PJ_TIMER_DEBUG
+PJ_DEF(void) pj_timer_heap_dump(pj_timer_heap_t *ht)
+{
+ lock_timer_heap(ht);
+
+ PJ_LOG(3,(THIS_FILE, "Dumping timer heap:"));
+ PJ_LOG(3,(THIS_FILE, " Cur size: %d entries, max: %d",
+ (int)ht->cur_size, (int)ht->max_size));
+
+ if (ht->cur_size) {
+ unsigned i;
+ pj_time_val now;
+
+ PJ_LOG(3,(THIS_FILE, " Entries: "));
+ PJ_LOG(3,(THIS_FILE, " _id\tId\tElapsed\tSource"));
+ PJ_LOG(3,(THIS_FILE, " ----------------------------------"));
+
+ pj_gettickcount(&now);
+
+ for (i=0; i<(unsigned)ht->cur_size; ++i) {
+ pj_timer_entry *e = ht->heap[i];
+ pj_time_val delta;
+
+ if (PJ_TIME_VAL_LTE(e->_timer_value, now))
+ delta.sec = delta.msec = 0;
+ else {
+ delta = e->_timer_value;
+ PJ_TIME_VAL_SUB(delta, now);
+ }
+
+ PJ_LOG(3,(THIS_FILE, " %d\t%d\t%d.%03d\t%s:%d",
+ e->_timer_id, e->id,
+ (int)delta.sec, (int)delta.msec,
+ e->src_file, e->src_line));
+ }
+ }
+
+ unlock_timer_heap(ht);
+}
+#endif
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-02 03:05:22 +0000