Initial checkin of gRPC to third_party/

third_party/grpc/src/core/iomgr/pollset_windows.c

+/*
+ *
+ * Copyright 2015-2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <grpc/support/port_platform.h>
+
+#ifdef GPR_WINSOCK_SOCKET
+
+#include <grpc/support/log.h>
+#include <grpc/support/thd.h>
+
+#include "src/core/iomgr/iomgr_internal.h"
+#include "src/core/iomgr/iocp_windows.h"
+#include "src/core/iomgr/pollset.h"
+#include "src/core/iomgr/pollset_windows.h"
+
+gpr_mu grpc_polling_mu;
+static grpc_pollset_worker *g_active_poller;
+static grpc_pollset_worker g_global_root_worker;
+
+void grpc_pollset_global_init() {
+  gpr_mu_init(&grpc_polling_mu);
+  g_active_poller = NULL;
+  g_global_root_worker.links[GRPC_POLLSET_WORKER_LINK_GLOBAL].next =
+      g_global_root_worker.links[GRPC_POLLSET_WORKER_LINK_GLOBAL].prev =
+          &g_global_root_worker;
+}
+
+void grpc_pollset_global_shutdown() { gpr_mu_destroy(&grpc_polling_mu); }
+
+static void remove_worker(grpc_pollset_worker *worker,
+                          grpc_pollset_worker_link_type type) {
+  worker->links[type].prev->links[type].next = worker->links[type].next;
+  worker->links[type].next->links[type].prev = worker->links[type].prev;
+  worker->links[type].next = worker->links[type].prev = worker;
+}
+
+static int has_workers(grpc_pollset_worker *root,
+                       grpc_pollset_worker_link_type type) {
+  return root->links[type].next != root;
+}
+
+static grpc_pollset_worker *pop_front_worker(
+    grpc_pollset_worker *root, grpc_pollset_worker_link_type type) {
+  if (has_workers(root, type)) {
+    grpc_pollset_worker *w = root->links[type].next;
+    remove_worker(w, type);
+    return w;
+  } else {
+    return NULL;
+  }
+}
+
+static void push_front_worker(grpc_pollset_worker *root,
+                              grpc_pollset_worker_link_type type,
+                              grpc_pollset_worker *worker) {
+  worker->links[type].prev = root;
+  worker->links[type].next = worker->links[type].prev->links[type].next;
+  worker->links[type].prev->links[type].next =
+      worker->links[type].next->links[type].prev = worker;
+}
+
+size_t grpc_pollset_size(void) { return sizeof(grpc_pollset); }
+
+/* There isn't really any such thing as a pollset under Windows, due to the
+   nature of the IO completion ports. We're still going to provide a minimal
+   set of features for the sake of the rest of grpc. But grpc_pollset_work
+   won't actually do any polling, and return as quickly as possible. */
+
+void grpc_pollset_init(grpc_pollset *pollset, gpr_mu **mu) {
+  *mu = &grpc_polling_mu;
+  memset(pollset, 0, sizeof(*pollset));
+  pollset->root_worker.links[GRPC_POLLSET_WORKER_LINK_POLLSET].next =
+      pollset->root_worker.links[GRPC_POLLSET_WORKER_LINK_POLLSET].prev =
+          &pollset->root_worker;
+}
+
+void grpc_pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
+                           grpc_closure *closure) {
+  pollset->shutting_down = 1;
+  grpc_pollset_kick(pollset, GRPC_POLLSET_KICK_BROADCAST);
+  if (!pollset->is_iocp_worker) {
+    grpc_exec_ctx_enqueue(exec_ctx, closure, true, NULL);
+  } else {
+    pollset->on_shutdown = closure;
+  }
+}
+
+void grpc_pollset_destroy(grpc_pollset *pollset) {}
+
+void grpc_pollset_reset(grpc_pollset *pollset) {
+  GPR_ASSERT(pollset->shutting_down);
+  GPR_ASSERT(
+      !has_workers(&pollset->root_worker, GRPC_POLLSET_WORKER_LINK_POLLSET));
+  pollset->shutting_down = 0;
+  pollset->is_iocp_worker = 0;
+  pollset->kicked_without_pollers = 0;
+  pollset->on_shutdown = NULL;
+}
+
+void grpc_pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
+                       grpc_pollset_worker **worker_hdl, gpr_timespec now,
+                       gpr_timespec deadline) {
+  grpc_pollset_worker worker;
+  *worker_hdl = &worker;
+
+  int added_worker = 0;
+  worker.links[GRPC_POLLSET_WORKER_LINK_POLLSET].next =
+      worker.links[GRPC_POLLSET_WORKER_LINK_POLLSET].prev =
+          worker.links[GRPC_POLLSET_WORKER_LINK_GLOBAL].next =
+              worker.links[GRPC_POLLSET_WORKER_LINK_GLOBAL].prev = NULL;
+  worker.kicked = 0;
+  worker.pollset = pollset;
+  gpr_cv_init(&worker.cv);
+  if (!pollset->kicked_without_pollers && !pollset->shutting_down) {
+    if (g_active_poller == NULL) {
+      grpc_pollset_worker *next_worker;
+      /* become poller */
+      pollset->is_iocp_worker = 1;
+      g_active_poller = &worker;
+      gpr_mu_unlock(&grpc_polling_mu);
+      grpc_iocp_work(exec_ctx, deadline);
+      grpc_exec_ctx_flush(exec_ctx);
+      gpr_mu_lock(&grpc_polling_mu);
+      pollset->is_iocp_worker = 0;
+      g_active_poller = NULL;
+      /* try to get a worker from this pollsets worker list */
+      next_worker = pop_front_worker(&pollset->root_worker,
+                                     GRPC_POLLSET_WORKER_LINK_POLLSET);
+      if (next_worker == NULL) {
+        /* try to get a worker from the global list */
+        next_worker = pop_front_worker(&g_global_root_worker,
+                                       GRPC_POLLSET_WORKER_LINK_GLOBAL);
+      }
+      if (next_worker != NULL) {
+        next_worker->kicked = 1;
+        gpr_cv_signal(&next_worker->cv);
+      }
+
+      if (pollset->shutting_down && pollset->on_shutdown != NULL) {
+        grpc_exec_ctx_enqueue(exec_ctx, pollset->on_shutdown, true, NULL);
+        pollset->on_shutdown = NULL;
+      }
+      goto done;
+    }
+    push_front_worker(&g_global_root_worker, GRPC_POLLSET_WORKER_LINK_GLOBAL,
+                      &worker);
+    push_front_worker(&pollset->root_worker, GRPC_POLLSET_WORKER_LINK_POLLSET,
+                      &worker);
+    added_worker = 1;
+    while (!worker.kicked) {
+      if (gpr_cv_wait(&worker.cv, &grpc_polling_mu, deadline)) {
+        break;
+      }
+    }
+  } else {
+    pollset->kicked_without_pollers = 0;
+  }
+done:
+  if (!grpc_closure_list_empty(exec_ctx->closure_list)) {
+    gpr_mu_unlock(&grpc_polling_mu);
+    grpc_exec_ctx_flush(exec_ctx);
+    gpr_mu_lock(&grpc_polling_mu);
+  }
+  if (added_worker) {
+    remove_worker(&worker, GRPC_POLLSET_WORKER_LINK_GLOBAL);
+    remove_worker(&worker, GRPC_POLLSET_WORKER_LINK_POLLSET);
+  }
+  gpr_cv_destroy(&worker.cv);
+  *worker_hdl = NULL;
+}
+
+void grpc_pollset_kick(grpc_pollset *p, grpc_pollset_worker *specific_worker) {
+  if (specific_worker != NULL) {
+    if (specific_worker == GRPC_POLLSET_KICK_BROADCAST) {
+      for (specific_worker =
+               p->root_worker.links[GRPC_POLLSET_WORKER_LINK_POLLSET].next;
+           specific_worker != &p->root_worker;
+           specific_worker =
+               specific_worker->links[GRPC_POLLSET_WORKER_LINK_POLLSET].next) {
+        specific_worker->kicked = 1;
+        gpr_cv_signal(&specific_worker->cv);
+      }
+      p->kicked_without_pollers = 1;
+      if (p->is_iocp_worker) {
+        grpc_iocp_kick();
+      }
+    } else {
+      if (p->is_iocp_worker && g_active_poller == specific_worker) {
+        grpc_iocp_kick();
+      } else {
+        specific_worker->kicked = 1;
+        gpr_cv_signal(&specific_worker->cv);
+      }
+    }
+  } else {
+    specific_worker =
+        pop_front_worker(&p->root_worker, GRPC_POLLSET_WORKER_LINK_POLLSET);
+    if (specific_worker != NULL) {
+      grpc_pollset_kick(p, specific_worker);
+    } else if (p->is_iocp_worker) {
+      grpc_iocp_kick();
+    } else {
+      p->kicked_without_pollers = 1;
+    }
+  }
+}
+
+void grpc_kick_poller(void) { grpc_iocp_kick(); }
+
+#endif /* GPR_WINSOCK_SOCKET */