1 files changed, 365 insertions, 0 deletions
diff --git a/src/core/lib/iomgr/tcp_custom.cc b/src/core/lib/iomgr/tcp_custom.cc
new file mode 100644
index 0000000000..2b1fc93028
--- /dev/null
+++ b/src/core/lib/iomgr/tcp_custom.cc
@@ -0,0 +1,365 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * 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.
+ *
+ */
+
+#include <grpc/support/port_platform.h>
+
+#include "src/core/lib/iomgr/port.h"
+
+#include <limits.h>
+#include <string.h>
+
+#include <grpc/slice_buffer.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+
+#include "src/core/lib/iomgr/error.h"
+#include "src/core/lib/iomgr/iomgr_custom.h"
+#include "src/core/lib/iomgr/network_status_tracker.h"
+#include "src/core/lib/iomgr/resource_quota.h"
+#include "src/core/lib/iomgr/tcp_client.h"
+#include "src/core/lib/iomgr/tcp_custom.h"
+#include "src/core/lib/iomgr/tcp_server.h"
+#include "src/core/lib/slice/slice_internal.h"
+#include "src/core/lib/slice/slice_string_helpers.h"
+
+#define GRPC_TCP_DEFAULT_READ_SLICE_SIZE 8192
+
+extern grpc_core::TraceFlag grpc_tcp_trace;
+
+grpc_socket_vtable* grpc_custom_socket_vtable = nullptr;
+extern grpc_tcp_server_vtable custom_tcp_server_vtable;
+extern grpc_tcp_client_vtable custom_tcp_client_vtable;
+
+void grpc_custom_endpoint_init(grpc_socket_vtable* impl) {
+  grpc_custom_socket_vtable = impl;
+  grpc_set_tcp_client_impl(&custom_tcp_client_vtable);
+  grpc_set_tcp_server_impl(&custom_tcp_server_vtable);
+}
+
+typedef struct {
+  grpc_endpoint base;
+  gpr_refcount refcount;
+  grpc_custom_socket* socket;
+
+  grpc_closure* read_cb;
+  grpc_closure* write_cb;
+
+  grpc_slice_buffer* read_slices;
+  grpc_slice_buffer* write_slices;
+
+  grpc_resource_user* resource_user;
+  grpc_resource_user_slice_allocator slice_allocator;
+
+  bool shutting_down;
+
+  char* peer_string;
+} custom_tcp_endpoint;
+
+static void tcp_free(grpc_custom_socket* s) {
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)s->endpoint;
+  grpc_resource_user_unref(tcp->resource_user);
+  gpr_free(tcp->peer_string);
+  gpr_free(tcp);
+  s->refs--;
+  if (s->refs == 0) {
+    grpc_custom_socket_vtable->destroy(s);
+    gpr_free(s);
+  }
+}
+
+#ifndef NDEBUG
+#define TCP_UNREF(tcp, reason) tcp_unref((tcp), (reason), __FILE__, __LINE__)
+#define TCP_REF(tcp, reason) tcp_ref((tcp), (reason), __FILE__, __LINE__)
+static void tcp_unref(custom_tcp_endpoint* tcp, const char* reason,
+                      const char* file, int line) {
+  if (grpc_tcp_trace.enabled()) {
+    gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_ERROR,
+            "TCP unref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp->socket, reason,
+            val, val - 1);
+  }
+  if (gpr_unref(&tcp->refcount)) {
+    tcp_free(tcp->socket);
+  }
+}
+
+static void tcp_ref(custom_tcp_endpoint* tcp, const char* reason,
+                    const char* file, int line) {
+  if (grpc_tcp_trace.enabled()) {
+    gpr_atm val = gpr_atm_no_barrier_load(&tcp->refcount.count);
+    gpr_log(file, line, GPR_LOG_SEVERITY_ERROR,
+            "TCP   ref %p : %s %" PRIdPTR " -> %" PRIdPTR, tcp->socket, reason,
+            val, val + 1);
+  }
+  gpr_ref(&tcp->refcount);
+}
+#else
+#define TCP_UNREF(tcp, reason) tcp_unref((tcp))
+#define TCP_REF(tcp, reason) tcp_ref((tcp))
+static void tcp_unref(custom_tcp_endpoint* tcp) {
+  if (gpr_unref(&tcp->refcount)) {
+    tcp_free(tcp->socket);
+  }
+}
+
+static void tcp_ref(custom_tcp_endpoint* tcp) { gpr_ref(&tcp->refcount); }
+#endif
+
+static void call_read_cb(custom_tcp_endpoint* tcp, grpc_error* error) {
+  grpc_closure* cb = tcp->read_cb;
+  if (grpc_tcp_trace.enabled()) {
+    gpr_log(GPR_DEBUG, "TCP:%p call_cb %p %p:%p", tcp->socket, cb, cb->cb,
+            cb->cb_arg);
+    size_t i;
+    const char* str = grpc_error_string(error);
+    gpr_log(GPR_DEBUG, "read: error=%s", str);
+
+    for (i = 0; i < tcp->read_slices->count; i++) {
+      char* dump = grpc_dump_slice(tcp->read_slices->slices[i],
+                                   GPR_DUMP_HEX | GPR_DUMP_ASCII);
+      gpr_log(GPR_DEBUG, "READ %p (peer=%s): %s", tcp, tcp->peer_string, dump);
+      gpr_free(dump);
+    }
+  }
+  TCP_UNREF(tcp, "read");
+  tcp->read_slices = nullptr;
+  tcp->read_cb = nullptr;
+  GRPC_CLOSURE_RUN(cb, error);
+}
+
+static void custom_read_callback(grpc_custom_socket* socket, size_t nread,
+                                 grpc_error* error) {
+  grpc_core::ExecCtx exec_ctx;
+  grpc_slice_buffer garbage;
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)socket->endpoint;
+  if (error == GRPC_ERROR_NONE && nread == 0) {
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("EOF");
+  }
+  if (error == GRPC_ERROR_NONE) {
+    // Successful read
+    if ((size_t)nread < tcp->read_slices->length) {
+      /* TODO(murgatroid99): Instead of discarding the unused part of the read
+       * buffer, reuse it as the next read buffer. */
+      grpc_slice_buffer_init(&garbage);
+      grpc_slice_buffer_trim_end(
+          tcp->read_slices, tcp->read_slices->length - (size_t)nread, &garbage);
+      grpc_slice_buffer_reset_and_unref_internal(&garbage);
+    }
+  } else {
+    grpc_slice_buffer_reset_and_unref_internal(tcp->read_slices);
+  }
+  call_read_cb(tcp, error);
+}
+
+static void tcp_read_allocation_done(void* tcpp, grpc_error* error) {
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)tcpp;
+  if (grpc_tcp_trace.enabled()) {
+    gpr_log(GPR_DEBUG, "TCP:%p read_allocation_done: %s", tcp->socket,
+            grpc_error_string(error));
+  }
+  if (error == GRPC_ERROR_NONE) {
+    /* Before calling read, we allocate a buffer with exactly one slice
+     * to tcp->read_slices and wait for the callback indicating that the
+     * allocation was successful. So slices[0] should always exist here */
+    char* buffer = (char*)GRPC_SLICE_START_PTR(tcp->read_slices->slices[0]);
+    size_t len = GRPC_SLICE_LENGTH(tcp->read_slices->slices[0]);
+    grpc_custom_socket_vtable->read(tcp->socket, buffer, len,
+                                    custom_read_callback);
+  } else {
+    grpc_slice_buffer_reset_and_unref_internal(tcp->read_slices);
+    call_read_cb(tcp, GRPC_ERROR_REF(error));
+  }
+  if (grpc_tcp_trace.enabled()) {
+    const char* str = grpc_error_string(error);
+    gpr_log(GPR_DEBUG, "Initiating read on %p: error=%s", tcp->socket, str);
+  }
+}
+
+static void endpoint_read(grpc_endpoint* ep, grpc_slice_buffer* read_slices,
+                          grpc_closure* cb) {
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)ep;
+  GRPC_CUSTOM_IOMGR_ASSERT_SAME_THREAD();
+  GPR_ASSERT(tcp->read_cb == nullptr);
+  tcp->read_cb = cb;
+  tcp->read_slices = read_slices;
+  grpc_slice_buffer_reset_and_unref_internal(read_slices);
+  TCP_REF(tcp, "read");
+  grpc_resource_user_alloc_slices(&tcp->slice_allocator,
+                                  GRPC_TCP_DEFAULT_READ_SLICE_SIZE, 1,
+                                  tcp->read_slices);
+}
+
+static void custom_write_callback(grpc_custom_socket* socket,
+                                  grpc_error* error) {
+  grpc_core::ExecCtx exec_ctx;
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)socket->endpoint;
+  grpc_closure* cb = tcp->write_cb;
+  tcp->write_cb = nullptr;
+  if (grpc_tcp_trace.enabled()) {
+    const char* str = grpc_error_string(error);
+    gpr_log(GPR_DEBUG, "write complete on %p: error=%s", tcp->socket, str);
+  }
+  TCP_UNREF(tcp, "write");
+  GRPC_CLOSURE_SCHED(cb, error);
+}
+
+static void endpoint_write(grpc_endpoint* ep, grpc_slice_buffer* write_slices,
+                           grpc_closure* cb) {
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)ep;
+  GRPC_CUSTOM_IOMGR_ASSERT_SAME_THREAD();
+
+  if (grpc_tcp_trace.enabled()) {
+    size_t j;
+
+    for (j = 0; j < write_slices->count; j++) {
+      char* data = grpc_dump_slice(write_slices->slices[j],
+                                   GPR_DUMP_HEX | GPR_DUMP_ASCII);
+      gpr_log(GPR_DEBUG, "WRITE %p (peer=%s): %s", tcp->socket,
+              tcp->peer_string, data);
+      gpr_free(data);
+    }
+  }
+
+  if (tcp->shutting_down) {
+    GRPC_CLOSURE_SCHED(cb, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                               "TCP socket is shutting down"));
+    return;
+  }
+
+  GPR_ASSERT(tcp->write_cb == nullptr);
+  tcp->write_slices = write_slices;
+  GPR_ASSERT(tcp->write_slices->count <= UINT_MAX);
+  if (tcp->write_slices->count == 0) {
+    // No slices means we don't have to do anything,
+    // and libuv doesn't like empty writes
+    GRPC_CLOSURE_SCHED(cb, GRPC_ERROR_NONE);
+    return;
+  }
+  tcp->write_cb = cb;
+  TCP_REF(tcp, "write");
+  grpc_custom_socket_vtable->write(tcp->socket, tcp->write_slices,
+                                   custom_write_callback);
+}
+
+static void endpoint_add_to_pollset(grpc_endpoint* ep, grpc_pollset* pollset) {
+  // No-op. We're ignoring pollsets currently
+  (void)ep;
+  (void)pollset;
+}
+
+static void endpoint_add_to_pollset_set(grpc_endpoint* ep,
+                                        grpc_pollset_set* pollset) {
+  // No-op. We're ignoring pollsets currently
+  (void)ep;
+  (void)pollset;
+}
+
+static void endpoint_delete_from_pollset_set(grpc_endpoint* ep,
+                                             grpc_pollset_set* pollset) {
+  // No-op. We're ignoring pollsets currently
+  (void)ep;
+  (void)pollset;
+}
+
+static void endpoint_shutdown(grpc_endpoint* ep, grpc_error* why) {
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)ep;
+  if (!tcp->shutting_down) {
+    if (grpc_tcp_trace.enabled()) {
+      const char* str = grpc_error_string(why);
+      gpr_log(GPR_DEBUG, "TCP %p shutdown why=%s", tcp->socket, str);
+    }
+    tcp->shutting_down = true;
+    // GRPC_CLOSURE_SCHED(tcp->read_cb, GRPC_ERROR_REF(why));
+    // GRPC_CLOSURE_SCHED(tcp->write_cb, GRPC_ERROR_REF(why));
+    // tcp->read_cb = nullptr;
+    // tcp->write_cb = nullptr;
+    grpc_resource_user_shutdown(tcp->resource_user);
+    grpc_custom_socket_vtable->shutdown(tcp->socket);
+  }
+  GRPC_ERROR_UNREF(why);
+}
+
+static void custom_close_callback(grpc_custom_socket* socket) {
+  socket->refs--;
+  if (socket->refs == 0) {
+    grpc_custom_socket_vtable->destroy(socket);
+    gpr_free(socket);
+  } else if (socket->endpoint) {
+    grpc_core::ExecCtx exec_ctx;
+    custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)socket->endpoint;
+    TCP_UNREF(tcp, "destroy");
+  }
+}
+
+static void endpoint_destroy(grpc_endpoint* ep) {
+  grpc_network_status_unregister_endpoint(ep);
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)ep;
+  grpc_custom_socket_vtable->close(tcp->socket, custom_close_callback);
+}
+
+static char* endpoint_get_peer(grpc_endpoint* ep) {
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)ep;
+  return gpr_strdup(tcp->peer_string);
+}
+
+static grpc_resource_user* endpoint_get_resource_user(grpc_endpoint* ep) {
+  custom_tcp_endpoint* tcp = (custom_tcp_endpoint*)ep;
+  return tcp->resource_user;
+}
+
+static int endpoint_get_fd(grpc_endpoint* ep) { return -1; }
+
+static grpc_endpoint_vtable vtable = {endpoint_read,
+                                      endpoint_write,
+                                      endpoint_add_to_pollset,
+                                      endpoint_add_to_pollset_set,
+                                      endpoint_delete_from_pollset_set,
+                                      endpoint_shutdown,
+                                      endpoint_destroy,
+                                      endpoint_get_resource_user,
+                                      endpoint_get_peer,
+                                      endpoint_get_fd};
+
+grpc_endpoint* custom_tcp_endpoint_create(grpc_custom_socket* socket,
+                                          grpc_resource_quota* resource_quota,
+                                          char* peer_string) {
+  custom_tcp_endpoint* tcp =
+      (custom_tcp_endpoint*)gpr_malloc(sizeof(custom_tcp_endpoint));
+  grpc_core::ExecCtx exec_ctx;
+
+  if (grpc_tcp_trace.enabled()) {
+    gpr_log(GPR_DEBUG, "Creating TCP endpoint %p", socket);
+  }
+  memset(tcp, 0, sizeof(custom_tcp_endpoint));
+  socket->refs++;
+  socket->endpoint = (grpc_endpoint*)tcp;
+  tcp->socket = socket;
+  tcp->base.vtable = &vtable;
+  gpr_ref_init(&tcp->refcount, 1);
+  tcp->peer_string = gpr_strdup(peer_string);
+  tcp->shutting_down = false;
+  tcp->resource_user = grpc_resource_user_create(resource_quota, peer_string);
+  grpc_resource_user_slice_allocator_init(
+      &tcp->slice_allocator, tcp->resource_user, tcp_read_allocation_done, tcp);
+  /* Tell network status tracking code about the new endpoint */
+  grpc_network_status_register_endpoint(&tcp->base);
+
+  return &tcp->base;
+}