Merge branch 'upstream-libuv' into import-libuv

* upstream-libuv:
  libuv 2016-08-30 (897738b1)

1 files changed, 120 insertions, 0 deletions

diff --git a/Utilities/cmlibuv/src/unix/pthread-barrier.c b/Utilities/cmlibuv/src/unix/pthread-barrier.c
new file mode 100644
index 0000000..f57bf25
--- /dev/null
+++ b/Utilities/cmlibuv/src/unix/pthread-barrier.c
@@ -0,0 +1,120 @@
+/*
+Copyright (c) 2016, Kari Tristan Helgason <kthelgason@gmail.com>
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+#include "uv-common.h"
+#include "pthread-barrier.h"
+
+#include <stdlib.h>
+#include <assert.h>
+
+/* TODO: support barrier_attr */
+int pthread_barrier_init(pthread_barrier_t* barrier,
+                         const void* barrier_attr,
+                         unsigned count) {
+  int rc;
+  _uv_barrier* b;
+
+  if (barrier == NULL || count == 0)
+    return EINVAL;
+
+  if (barrier_attr != NULL)
+    return ENOTSUP;
+
+  b = uv__malloc(sizeof(*b));
+  if (b == NULL)
+    return ENOMEM;
+
+  b->in = 0;
+  b->out = 0;
+  b->threshold = count;
+
+  if ((rc = pthread_mutex_init(&b->mutex, NULL)) != 0)
+    goto error2;
+  if ((rc = pthread_cond_init(&b->cond, NULL)) != 0)
+    goto error;
+
+  barrier->b = b;
+  return 0;
+
+error:
+  pthread_mutex_destroy(&b->mutex);
+error2:
+  uv__free(b);
+  return rc;
+}
+
+int pthread_barrier_wait(pthread_barrier_t* barrier) {
+  int rc;
+  _uv_barrier* b;
+
+  if (barrier == NULL || barrier->b == NULL)
+    return EINVAL;
+
+  b = barrier->b;
+  /* Lock the mutex*/
+  if ((rc = pthread_mutex_lock(&b->mutex)) != 0)
+    return rc;
+
+  /* Increment the count. If this is the first thread to reach the threshold,
+     wake up waiters, unlock the mutex, then return
+     PTHREAD_BARRIER_SERIAL_THREAD. */
+  if (++b->in == b->threshold) {
+    b->in = 0;
+    b->out = b->threshold - 1;
+    assert(pthread_cond_signal(&b->cond) == 0);
+
+    pthread_mutex_unlock(&b->mutex);
+    return PTHREAD_BARRIER_SERIAL_THREAD;
+  }
+  /* Otherwise, wait for other threads until in is set to 0,
+     then return 0 to indicate this is not the first thread. */
+  do {
+    if ((rc = pthread_cond_wait(&b->cond, &b->mutex)) != 0)
+      break;
+  } while (b->in != 0);
+
+  /* mark thread exit */
+  b->out--;
+  pthread_cond_signal(&b->cond);
+  pthread_mutex_unlock(&b->mutex);
+  return rc;
+}
+
+int pthread_barrier_destroy(pthread_barrier_t* barrier) {
+  int rc;
+  _uv_barrier* b;
+
+  if (barrier == NULL || barrier->b == NULL)
+    return EINVAL;
+
+  b = barrier->b;
+
+  if ((rc = pthread_mutex_lock(&b->mutex)) != 0)
+    return rc;
+
+  if (b->in > 0 || b->out > 0)
+    rc = EBUSY;
+
+  pthread_mutex_unlock(&b->mutex);
+
+  if (rc)
+    return rc;
+
+  pthread_cond_destroy(&b->cond);
+  pthread_mutex_destroy(&b->mutex);
+  uv__free(barrier->b);
+  barrier->b = NULL;
+  return 0;
+}