Merge branch 'master' into gpr_review_tls

13 files changed, 135 insertions, 215 deletions

diff --git a/include/grpc++/alarm.h b/include/grpc++/alarm.h
index b43425e224..37d4189201 100644
--- a/include/grpc++/alarm.h
+++ b/include/grpc++/alarm.h
@@ -28,17 +28,16 @@
 #include <grpc++/impl/grpc_library.h>
 #include <grpc/grpc.h>
 
-struct grpc_alarm;
-
 namespace grpc {
 
-class CompletionQueue;
-
 /// A thin wrapper around \a grpc_alarm (see / \a / src/core/surface/alarm.h).
 class Alarm : private GrpcLibraryCodegen {
  public:
   /// Create an unset completion queue alarm
-  Alarm() : tag_(nullptr), alarm_(grpc_alarm_create(nullptr)) {}
+  Alarm();
+
+  /// Destroy the given completion queue alarm, cancelling it in the process.
+  ~Alarm();
 
   /// DEPRECATED: Create and set a completion queue alarm instance associated to
   /// \a cq.
@@ -48,10 +47,8 @@ class Alarm : private GrpcLibraryCodegen {
   /// internal::GrpcLibraryInitializer instance would need to be introduced
   /// here. \endinternal.
   template <typename T>
-  Alarm(CompletionQueue* cq, const T& deadline, void* tag)
-      : tag_(tag), alarm_(grpc_alarm_create(nullptr)) {
-    grpc_alarm_set(alarm_, cq->cq(), TimePoint<T>(deadline).raw_time(),
-                   static_cast<void*>(&tag_), nullptr);
+  Alarm(CompletionQueue* cq, const T& deadline, void* tag) : Alarm() {
+    SetInternal(cq, TimePoint<T>(deadline).raw_time(), tag);
   }
 
   /// Trigger an alarm instance on completion queue \a cq at the specified time.
@@ -60,9 +57,7 @@ class Alarm : private GrpcLibraryCodegen {
   /// event's success bit will be true, false otherwise (ie, upon cancellation).
   template <typename T>
   void Set(CompletionQueue* cq, const T& deadline, void* tag) {
-    tag_.Set(tag);
-    grpc_alarm_set(alarm_, cq->cq(), TimePoint<T>(deadline).raw_time(),
-                   static_cast<void*>(&tag_), nullptr);
+    SetInternal(cq, TimePoint<T>(deadline).raw_time(), tag);
   }
 
   /// Alarms aren't copyable.
@@ -70,43 +65,21 @@ class Alarm : private GrpcLibraryCodegen {
   Alarm& operator=(const Alarm&) = delete;
 
   /// Alarms are movable.
-  Alarm(Alarm&& rhs) : tag_(rhs.tag_), alarm_(rhs.alarm_) {
-    rhs.alarm_ = nullptr;
-  }
+  Alarm(Alarm&& rhs) : alarm_(rhs.alarm_) { rhs.alarm_ = nullptr; }
   Alarm& operator=(Alarm&& rhs) {
-    tag_ = rhs.tag_;
     alarm_ = rhs.alarm_;
     rhs.alarm_ = nullptr;
     return *this;
   }
 
-  /// Destroy the given completion queue alarm, cancelling it in the process.
-  ~Alarm() {
-    if (alarm_ != nullptr) grpc_alarm_destroy(alarm_, nullptr);
-  }
-
   /// Cancel a completion queue alarm. Calling this function over an alarm that
   /// has already fired has no effect.
-  void Cancel() {
-    if (alarm_ != nullptr) grpc_alarm_cancel(alarm_, nullptr);
-  }
+  void Cancel();
 
  private:
-  class AlarmEntry : public internal::CompletionQueueTag {
-   public:
-    AlarmEntry(void* tag) : tag_(tag) {}
-    void Set(void* tag) { tag_ = tag; }
-    bool FinalizeResult(void** tag, bool* status) override {
-      *tag = tag_;
-      return true;
-    }
-
-   private:
-    void* tag_;
-  };
+  void SetInternal(CompletionQueue* cq, gpr_timespec deadline, void* tag);
 
-  AlarmEntry tag_;
-  grpc_alarm* alarm_;  // owned
+  internal::CompletionQueueTag* alarm_;
 };
 
 }  // namespace grpc
diff --git a/include/grpc++/generic/generic_stub.h b/include/grpc++/generic/generic_stub.h
index d5064318cf..e72826bdc1 100644
--- a/include/grpc++/generic/generic_stub.h
+++ b/include/grpc++/generic/generic_stub.h
@@ -37,15 +37,6 @@ class GenericStub final {
   explicit GenericStub(std::shared_ptr<ChannelInterface> channel)
       : channel_(channel) {}
 
-  /// Begin a call to a named method \a method using \a context.
-  /// A tag \a tag will be delivered to \a cq when the call has been started
-  /// (i.e, initial metadata has been sent).
-  /// The return value only indicates whether or not registration of the call
-  /// succeeded (i.e. the call won't proceed if the return value is nullptr).
-  std::unique_ptr<GenericClientAsyncReaderWriter> Call(
-      ClientContext* context, const grpc::string& method, CompletionQueue* cq,
-      void* tag);
-
   /// Setup a call to a named method \a method using \a context, but don't
   /// start it. Let it be started explicitly with StartCall and a tag.
   /// The return value only indicates whether or not registration of the call
@@ -61,6 +52,16 @@ class GenericStub final {
       ClientContext* context, const grpc::string& method,
       const ByteBuffer& request, CompletionQueue* cq);
 
+  /// DEPRECATED for multi-threaded use
+  /// Begin a call to a named method \a method using \a context.
+  /// A tag \a tag will be delivered to \a cq when the call has been started
+  /// (i.e, initial metadata has been sent).
+  /// The return value only indicates whether or not registration of the call
+  /// succeeded (i.e. the call won't proceed if the return value is nullptr).
+  std::unique_ptr<GenericClientAsyncReaderWriter> Call(
+      ClientContext* context, const grpc::string& method, CompletionQueue* cq,
+      void* tag);
+
  private:
   std::shared_ptr<ChannelInterface> channel_;
 };
diff --git a/include/grpc++/impl/codegen/call.h b/include/grpc++/impl/codegen/call.h
index 2758e94c5e..c04526c59b 100644
--- a/include/grpc++/impl/codegen/call.h
+++ b/include/grpc++/impl/codegen/call.h
@@ -607,7 +607,7 @@ class CallOpSetInterface : public CompletionQueueTag {
   virtual void FillOps(grpc_call* call, grpc_op* ops, size_t* nops) = 0;
 };
 
-/// Primary implementaiton of CallOpSetInterface.
+/// Primary implementation of CallOpSetInterface.
 /// Since we cannot use variadic templates, we declare slots up to
 /// the maximum count of ops we'll need in a set. We leverage the
 /// empty base class optimization to slim this class (especially
@@ -624,7 +624,7 @@ class CallOpSet : public CallOpSetInterface,
                   public Op5,
                   public Op6 {
  public:
-  CallOpSet() : return_tag_(this) {}
+  CallOpSet() : return_tag_(this), call_(nullptr) {}
   void FillOps(grpc_call* call, grpc_op* ops, size_t* nops) override {
     this->Op1::AddOp(ops, nops);
     this->Op2::AddOp(ops, nops);
diff --git a/include/grpc++/impl/codegen/client_context.h b/include/grpc++/impl/codegen/client_context.h
index 61d97ce818..38cce27b99 100644
--- a/include/grpc++/impl/codegen/client_context.h
+++ b/include/grpc++/impl/codegen/client_context.h
@@ -289,7 +289,9 @@ class ClientContext {
     creds_ = creds;
   }
 
-  /// Return the compression algorithm to be used by the client call.
+  /// Return the compression algorithm the client call will request be used.
+  /// Note that the gRPC runtime may decide to ignore this request, for example,
+  /// due to resource constraints.
   grpc_compression_algorithm compression_algorithm() const {
     return compression_algorithm_;
   }
@@ -302,7 +304,10 @@ class ClientContext {
   /// Flag whether the initial metadata should be \a corked
   ///
   /// If \a corked is true, then the initial metadata will be coalesced with the
-  /// write of first message in the stream.
+  /// write of first message in the stream. As a result, any tag set for the
+  /// initial metadata operation (starting a client-streaming or bidi-streaming
+  /// RPC) will not actually be sent to the completion queue or delivered
+  /// via Next.
   ///
   /// \param corked The flag indicating whether the initial metadata is to be
   /// corked or not.
@@ -330,6 +335,10 @@ class ClientContext {
   /// already finished, it may still return success.
   ///
   /// There is no guarantee the call will be cancelled.
+  ///
+  /// Note that TryCancel() does not change any of the tags that are pending
+  /// on the completion queue. All pending tags will still be delivered
+  /// (though their ok result may reflect the effect of cancellation).
   void TryCancel();
 
   /// Global Callbacks
diff --git a/include/grpc++/impl/codegen/completion_queue.h b/include/grpc++/impl/codegen/completion_queue.h
index b8a7862578..83477d0489 100644
--- a/include/grpc++/impl/codegen/completion_queue.h
+++ b/include/grpc++/impl/codegen/completion_queue.h
@@ -111,12 +111,83 @@ class CompletionQueue : private GrpcLibraryCodegen {
 
   /// Tri-state return for AsyncNext: SHUTDOWN, GOT_EVENT, TIMEOUT.
   enum NextStatus {
-    SHUTDOWN,   ///< The completion queue has been shutdown.
+    SHUTDOWN,   ///< The completion queue has been shutdown and fully-drained
     GOT_EVENT,  ///< Got a new event; \a tag will be filled in with its
                 ///< associated value; \a ok indicating its success.
     TIMEOUT     ///< deadline was reached.
   };
 
+  /// Read from the queue, blocking until an event is available or the queue is
+  /// shutting down.
+  ///
+  /// \param tag[out] Updated to point to the read event's tag.
+  /// \param ok[out] true if read a successful event, false otherwise.
+  ///
+  /// Note that each tag sent to the completion queue (through RPC operations
+  /// or alarms) will be delivered out of the completion queue by a call to
+  /// Next (or a related method), regardless of whether the operation succeeded
+  /// or not. Success here means that this operation completed in the normal
+  /// valid manner.
+  ///
+  /// Server-side RPC request: \a ok indicates that the RPC has indeed
+  /// been started. If it is false, the server has been Shutdown
+  /// before this particular call got matched to an incoming RPC.
+  ///
+  /// Client-side StartCall/RPC invocation: \a ok indicates that the RPC is
+  /// going to go to the wire. If it is false, it not going to the wire. This
+  /// would happen if the channel is either permanently broken or
+  /// transiently broken but with the fail-fast option. (Note that async unary
+  /// RPCs don't post a CQ tag at this point, nor do client-streaming
+  /// or bidi-streaming RPCs that have the initial metadata corked option set.)
+  ///
+  /// Client-side Write, Client-side WritesDone, Server-side Write,
+  /// Server-side Finish, Server-side SendInitialMetadata (which is
+  /// typically included in Write or Finish when not done explicitly):
+  /// \a ok means that the data/metadata/status/etc is going to go to the
+  /// wire. If it is false, it not going to the wire because the call
+  /// is already dead (i.e., canceled, deadline expired, other side
+  /// dropped the channel, etc).
+  ///
+  /// Client-side Read, Server-side Read, Client-side
+  /// RecvInitialMetadata (which is typically included in Read if not
+  /// done explicitly): \a ok indicates whether there is a valid message
+  /// that got read. If not, you know that there are certainly no more
+  /// messages that can ever be read from this stream. For the client-side
+  /// operations, this only happens because the call is dead. For the
+  /// server-sider operation, though, this could happen because the client
+  /// has done a WritesDone already.
+  ///
+  /// Client-side Finish: \a ok should always be true
+  ///
+  /// Server-side AsyncNotifyWhenDone: \a ok should always be true
+  ///
+  /// Alarm: \a ok is true if it expired, false if it was canceled
+  ///
+  /// \return true if got an event, false if the queue is fully drained and
+  ///         shut down.
+  bool Next(void** tag, bool* ok) {
+    return (AsyncNextInternal(tag, ok,
+                              g_core_codegen_interface->gpr_inf_future(
+                                  GPR_CLOCK_REALTIME)) != SHUTDOWN);
+  }
+
+  /// Read from the queue, blocking up to \a deadline (or the queue's shutdown).
+  /// Both \a tag and \a ok are updated upon success (if an event is available
+  /// within the \a deadline).  A \a tag points to an arbitrary location usually
+  /// employed to uniquely identify an event.
+  ///
+  /// \param tag[out] Upon sucess, updated to point to the event's tag.
+  /// \param ok[out] Upon sucess, true if a successful event, false otherwise
+  ///        See documentation for CompletionQueue::Next for explanation of ok
+  /// \param deadline[in] How long to block in wait for an event.
+  ///
+  /// \return The type of event read.
+  template <typename T>
+  NextStatus AsyncNext(void** tag, bool* ok, const T& deadline) {
+    TimePoint<T> deadline_tp(deadline);
+    return AsyncNextInternal(tag, ok, deadline_tp.raw_time());
+  }
+
   /// EXPERIMENTAL
   /// First executes \a F, then reads from the queue, blocking up to
   /// \a deadline (or the queue's shutdown).
@@ -141,44 +212,16 @@ class CompletionQueue : private GrpcLibraryCodegen {
     }
   }
 
-  /// Read from the queue, blocking up to \a deadline (or the queue's shutdown).
-  /// Both \a tag and \a ok are updated upon success (if an event is available
-  /// within the \a deadline).  A \a tag points to an arbitrary location usually
-  /// employed to uniquely identify an event.
-  ///
-  /// \param tag[out] Upon sucess, updated to point to the event's tag.
-  /// \param ok[out] Upon sucess, true if read a regular event, false otherwise.
-  /// \param deadline[in] How long to block in wait for an event.
-  ///
-  /// \return The type of event read.
-  template <typename T>
-  NextStatus AsyncNext(void** tag, bool* ok, const T& deadline) {
-    TimePoint<T> deadline_tp(deadline);
-    return AsyncNextInternal(tag, ok, deadline_tp.raw_time());
-  }
-
-  /// Read from the queue, blocking until an event is available or the queue is
-  /// shutting down.
-  ///
-  /// \param tag[out] Updated to point to the read event's tag.
-  /// \param ok[out] true if read a regular event, false otherwise.
-  ///
-  /// \return true if read a regular event, false if the queue is shutting down.
-  bool Next(void** tag, bool* ok) {
-    return (AsyncNextInternal(tag, ok,
-                              g_core_codegen_interface->gpr_inf_future(
-                                  GPR_CLOCK_REALTIME)) != SHUTDOWN);
-  }
-
   /// Request the shutdown of the queue.
   ///
   /// \warning This method must be called at some point if this completion queue
-  /// is accessed with Next or AsyncNext. Once invoked, \a Next
-  /// will start to return false and \a AsyncNext will return \a
-  /// NextStatus::SHUTDOWN. Only once either one of these methods does that
-  /// (that is, once the queue has been \em drained) can an instance of this
-  /// class be destroyed. Also note that applications must ensure that
-  /// no work is enqueued on this completion queue after this method is called.
+  /// is accessed with Next or AsyncNext. \a Next will not return false
+  /// until this method has been called and all pending tags have been drained.
+  /// (Likewise for \a AsyncNext returning \a NextStatus::SHUTDOWN .)
+  /// Only once either one of these methods does that (that is, once the queue
+  /// has been \em drained) can an instance of this class be destroyed.
+  /// Also note that applications must ensure that no work is enqueued on this
+  /// completion queue after this method is called.
   void Shutdown();
 
   /// Returns a \em raw pointer to the underlying \a grpc_completion_queue
diff --git a/include/grpc++/impl/codegen/proto_utils.h b/include/grpc++/impl/codegen/proto_utils.h
index b7636034d4..209250bba2 100644
--- a/include/grpc++/impl/codegen/proto_utils.h
+++ b/include/grpc++/impl/codegen/proto_utils.h
@@ -59,18 +59,22 @@ class GrpcBufferWriter : public ::grpc::protobuf::io::ZeroCopyOutputStream {
   bool Next(void** data, int* size) override {
     // Protobuf should not ask for more memory than total_size_.
     GPR_CODEGEN_ASSERT(byte_count_ < total_size_);
+    size_t remain = total_size_ - byte_count_;
     if (have_backup_) {
       slice_ = backup_slice_;
       have_backup_ = false;
+      if (GRPC_SLICE_LENGTH(slice_) > remain) {
+        GRPC_SLICE_SET_LENGTH(slice_, remain);
+      }
     } else {
       // When less than a whole block is needed, only allocate that much.
       // But make sure the allocated slice is not inlined.
-      size_t remain = total_size_ - byte_count_ > block_size_
-                          ? block_size_
-                          : total_size_ - byte_count_;
+      size_t allocate_length =
+          remain > static_cast<size_t>(block_size_) ? block_size_ : remain;
       slice_ = g_core_codegen_interface->grpc_slice_malloc(
-          remain > GRPC_SLICE_INLINED_SIZE ? remain
-                                           : GRPC_SLICE_INLINED_SIZE + 1);
+          allocate_length > GRPC_SLICE_INLINED_SIZE
+              ? allocate_length
+              : GRPC_SLICE_INLINED_SIZE + 1);
     }
     *data = GRPC_SLICE_START_PTR(slice_);
     // On win x64, int is only 32bit
diff --git a/include/grpc++/impl/codegen/server_context.h b/include/grpc++/impl/codegen/server_context.h
index a2d6967bf8..57347f4fcd 100644
--- a/include/grpc++/impl/codegen/server_context.h
+++ b/include/grpc++/impl/codegen/server_context.h
@@ -151,6 +151,10 @@ class ServerContext {
   /// The only exception is that if the serverhandler is already returning an
   /// error status code, it is ok to not return Status::CANCELLED even if
   /// TryCancel() was called.
+  ///
+  /// Note that TryCancel() does not change any of the tags that are pending
+  /// on the completion queue. All pending tags will still be delivered
+  /// (though their ok result may reflect the effect of cancellation).
   void TryCancel() const;
 
   /// Return a collection of initial metadata key-value pairs sent from the
@@ -185,7 +189,10 @@ class ServerContext {
   /// \a set_compression_level.
   bool compression_level_set() const { return compression_level_set_; }
 
-  /// Return the compression algorithm to be used by the server call.
+  /// Return the compression algorithm the server call will request be used.
+  /// Note that the gRPC runtime may decide to ignore this request, for example,
+  /// due to resource constraints, or if the server is aware the client doesn't
+  /// support the requested algorithm.
   grpc_compression_algorithm compression_algorithm() const {
     return compression_algorithm_;
   }
diff --git a/include/grpc/compression_ruby.h b/include/grpc/compression_ruby.h
deleted file mode 100644
index b063b2b529..0000000000
--- a/include/grpc/compression_ruby.h
+++ /dev/null
@@ -1,48 +0,0 @@
-/*
- *
- * Copyright 2017 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.
- *
- */
-
-#ifndef GRPC_COMPRESSION_RUBY_H
-#define GRPC_COMPRESSION_RUBY_H
-
-#include <grpc/impl/codegen/port_platform.h>
-
-#include <grpc/impl/codegen/compression_types.h>
-#include <grpc/slice.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/** Parses the \a slice as a grpc_compression_algorithm instance and updating \a
- * algorithm following algorithm names compatible with Ruby. Returns 1 upon
- * success, 0 otherwise. */
-GRPCAPI int grpc_compression_algorithm_parse_ruby(
-    grpc_slice value, grpc_compression_algorithm* algorithm);
-
-/** Updates \a name with the encoding name corresponding to a valid \a
- * algorithm. The \a name follows names compatible with Ruby. Note that \a name
- * is statically allocated and must *not* be freed. Returns 1 upon success, 0
- * otherwise. */
-GRPCAPI int grpc_compression_algorithm_name_ruby(
-    grpc_compression_algorithm algorithm, const char** name);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* GRPC_COMPRESSION_RUBY_H */
diff --git a/include/grpc/grpc.h b/include/grpc/grpc.h
index f083bc591e..47d749c728 100644
--- a/include/grpc/grpc.h
+++ b/include/grpc/grpc.h
@@ -160,25 +160,6 @@ GRPCAPI void grpc_completion_queue_thread_local_cache_init(
 GRPCAPI int grpc_completion_queue_thread_local_cache_flush(
     grpc_completion_queue* cq, void** tag, int* ok);
 
-/** Create a completion queue alarm instance */
-GRPCAPI grpc_alarm* grpc_alarm_create(void* reserved);
-
-/** Set a completion queue alarm instance associated to \a cq.
- *
- * Once the alarm expires (at \a deadline) or it's cancelled (see \a
- * grpc_alarm_cancel), an event with tag \a tag will be added to \a cq. If the
- * alarm expired, the event's success bit will be true, false otherwise (ie,
- * upon cancellation). */
-GRPCAPI void grpc_alarm_set(grpc_alarm* alarm, grpc_completion_queue* cq,
-                            gpr_timespec deadline, void* tag, void* reserved);
-
-/** Cancel a completion queue alarm. Calling this function over an alarm that
- * has already fired has no effect. */
-GRPCAPI void grpc_alarm_cancel(grpc_alarm* alarm, void* reserved);
-
-/** Destroy the given completion queue alarm, cancelling it in the process. */
-GRPCAPI void grpc_alarm_destroy(grpc_alarm* alarm, void* reserved);
-
 /** Check the connectivity state of a channel. */
 GRPCAPI grpc_connectivity_state grpc_channel_check_connectivity_state(
     grpc_channel* channel, int try_to_connect);
diff --git a/include/grpc/impl/codegen/compression_types.h b/include/grpc/impl/codegen/compression_types.h
index ddc667fcdb..be9dd2d8e7 100644
--- a/include/grpc/impl/codegen/compression_types.h
+++ b/include/grpc/impl/codegen/compression_types.h
@@ -55,8 +55,8 @@ extern "C" {
 /** The various compression algorithms supported by gRPC */
 typedef enum {
   GRPC_COMPRESS_NONE = 0,
-  GRPC_COMPRESS_MESSAGE_DEFLATE,
-  GRPC_COMPRESS_MESSAGE_GZIP,
+  GRPC_COMPRESS_DEFLATE,
+  GRPC_COMPRESS_GZIP,
   GRPC_COMPRESS_STREAM_GZIP,
   /* TODO(ctiller): snappy */
   GRPC_COMPRESS_ALGORITHMS_COUNT
diff --git a/include/grpc/impl/codegen/grpc_types.h b/include/grpc/impl/codegen/grpc_types.h
index e5aa29b88a..d64b23f332 100644
--- a/include/grpc/impl/codegen/grpc_types.h
+++ b/include/grpc/impl/codegen/grpc_types.h
@@ -239,6 +239,9 @@ typedef struct {
 /** The time between the first and second connection attempts, in ms */
 #define GRPC_ARG_INITIAL_RECONNECT_BACKOFF_MS \
   "grpc.initial_reconnect_backoff_ms"
+/** Minimum amount of time between DNS resolutions, in ms */
+#define GRPC_ARG_DNS_MIN_TIME_BETWEEN_RESOLUTIONS_MS \
+  "grpc.dns_min_time_between_resolutions_ms"
 /** The timeout used on servers for finishing handshaking on an incoming
     connection.  Defaults to 120 seconds. */
 #define GRPC_ARG_SERVER_HANDSHAKE_TIMEOUT_MS "grpc.server_handshake_timeout_ms"
diff --git a/include/grpc/module.modulemap b/include/grpc/module.modulemap
index cff98312c0..ba66c28fb3 100644
--- a/include/grpc/module.modulemap
+++ b/include/grpc/module.modulemap
@@ -7,7 +7,6 @@ framework module grpc {
   header "support/avl.h"
   header "support/cmdline.h"
   header "support/cpu.h"
-  header "support/host_port.h"
   header "support/log.h"
   header "support/log_windows.h"
   header "support/port_platform.h"
@@ -44,7 +43,6 @@ framework module grpc {
   header "byte_buffer.h"
   header "byte_buffer_reader.h"
   header "compression.h"
-  header "compression_ruby.h"
   header "fork.h"
   header "grpc.h"
   header "grpc_posix.h"
diff --git a/include/grpc/support/host_port.h b/include/grpc/support/host_port.h
deleted file mode 100644
index 9805811bfb..0000000000
--- a/include/grpc/support/host_port.h
+++ /dev/null
@@ -1,51 +0,0 @@
-/*
- *
- * Copyright 2015 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.
- *
- */
-
-#ifndef GRPC_SUPPORT_HOST_PORT_H
-#define GRPC_SUPPORT_HOST_PORT_H
-
-#include <grpc/support/port_platform.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/** Given a host and port, creates a newly-allocated string of the form
-   "host:port" or "[ho:st]:port", depending on whether the host contains colons
-   like an IPv6 literal.  If the host is already bracketed, then additional
-   brackets will not be added.
-
-   Usage is similar to gpr_asprintf: returns the number of bytes written
-   (excluding the final '\0'), and *out points to a string which must later be
-   destroyed using gpr_free().
-
-   In the unlikely event of an error, returns -1 and sets *out to NULL. */
-GPRAPI int gpr_join_host_port(char** out, const char* host, int port);
-
-/** Given a name in the form "host:port" or "[ho:st]:port", split into hostname
-   and port number, into newly allocated strings, which must later be
-   destroyed using gpr_free().
-   Return 1 on success, 0 on failure. Guarantees *host and *port == NULL on
-   failure. */
-GPRAPI int gpr_split_host_port(const char* name, char** host, char** port);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* GRPC_SUPPORT_HOST_PORT_H */