Moving gRPC support interfaces out of cronet and into a new component.

components/cronet/ios/cronet_c_for_grpc.h

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef COMPONENTS_CRONET_IOS_CRONET_C_FOR_GRPC_H_
-#define COMPONENTS_CRONET_IOS_CRONET_C_FOR_GRPC_H_
-
-#define CRONET_EXPORT __attribute__((visibility("default")))
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#include <stddef.h>
-
-/* Cronet Engine API. */
-
-/* Opaque object representing Cronet Engine. Created and configured outside
- * of this API to facilitate sharing with other components */
-typedef struct cronet_engine {
-  void* obj;
-  void* annotation;
-} cronet_engine;
-
-/* Cronet Bidirectional Stream API */
-
-/* Opaque object representing Cronet Bidirectional Stream. */
-typedef struct cronet_bidirectional_stream {
-  void* obj;
-  void* annotation;
-} cronet_bidirectional_stream;
-
-/* A single request or response header element. */
-typedef struct cronet_bidirectional_stream_header {
-  const char* key;
-  const char* value;
-} cronet_bidirectional_stream_header;
-
-/* Array of request or response headers or trailers. */
-typedef struct cronet_bidirectional_stream_header_array {
-  size_t count;
-  size_t capacity;
-  cronet_bidirectional_stream_header* headers;
-} cronet_bidirectional_stream_header_array;
-
-/* Set of callbacks used to receive callbacks from bidirectional stream. */
-typedef struct cronet_bidirectional_stream_callback {
-  /* Invoked when the stream is ready for reading and writing.
-   * Consumer may call cronet_bidirectional_stream_read() to start reading data.
-   * Consumer may call cronet_bidirectional_stream_write() to start writing
-   * data.
-   */
-  void (*on_stream_ready)(cronet_bidirectional_stream* stream);
-
-  /* Invoked when initial response headers are received.
-   * Consumer must call cronet_bidirectional_stream_read() to start reading.
-   * Consumer may call cronet_bidirectional_stream_write() to start writing or
-   * close the stream. Contents of |headers| is valid for duration of the call.
-   */
-  void (*on_response_headers_received)(
-      cronet_bidirectional_stream* stream,
-      const cronet_bidirectional_stream_header_array* headers,
-      const char* negotiated_protocol);
-
-  /* Invoked when data is read into the buffer passed to
-   * cronet_bidirectional_stream_read(). Only part of the buffer may be
-   * populated. To continue reading, call cronet_bidirectional_stream_read().
-   * It may be invoked after on_response_trailers_received()}, if there was
-   * pending read data before trailers were received.
-   *
-   * If |bytes_read| is 0, it means the remote side has signaled that it will
-   * send no more data; future calls to cronet_bidirectional_stream_read()
-   * will result in the on_data_read() callback or on_succeded() callback if
-   * cronet_bidirectional_stream_write() was invoked with end_of_stream set to
-   * true.
-   */
-  void (*on_read_completed)(cronet_bidirectional_stream* stream,
-                            char* data,
-                            int bytes_read);
-
-  /**
-   * Invoked when all data passed to cronet_bidirectional_stream_write() is
-   * sent. To continue writing, call cronet_bidirectional_stream_write().
-   */
-  void (*on_write_completed)(cronet_bidirectional_stream* stream,
-                             const char* data);
-
-  /* Invoked when trailers are received before closing the stream. Only invoked
-   * when server sends trailers, which it may not. May be invoked while there is
-   * read data remaining in local buffer. Contents of |trailers| is valid for
-   * duration of the call.
-   */
-  void (*on_response_trailers_received)(
-      cronet_bidirectional_stream* stream,
-      const cronet_bidirectional_stream_header_array* trailers);
-
-  /**
-   * Invoked when there is no data to be read or written and the stream is
-   * closed successfully remotely and locally. Once invoked, no further callback
-   * methods will be invoked.
-   */
-  void (*on_succeded)(cronet_bidirectional_stream* stream);
-
-  /**
-   * Invoked if the stream failed for any reason after
-   * cronet_bidirectional_stream_start(). HTTP/2 error codes are
-   * mapped to chrome net error codes. Once invoked, no further callback methods
-   * will be invoked.
-   */
-  void (*on_failed)(cronet_bidirectional_stream* stream, int net_error);
-
-  /**
-   * Invoked if the stream was canceled via
-   * cronet_bidirectional_stream_cancel(). Once invoked, no further callback
-   * methods will be invoked.
-   */
-  void (*on_canceled)(cronet_bidirectional_stream* stream);
-} cronet_bidirectional_stream_callback;
-
-/* Creates a new stream object that uses |engine| and |callback|. All stream
- * tasks are performed asynchronously on the |engine| network thread. |callback|
- * methods are invoked synchronously on the |engine| network thread, but must
- * not run tasks on the current thread to prevent blocking networking operations
- * and causing exceptions during shutdown. The |annotation| is stored in
- * bidirectional stream for arbitrary use by application.
- *
- * Returned |cronet_bidirectional_stream*| is owned by the caller, and must be
- * destroyed using |cronet_bidirectional_stream_destroy|.
- *
- * Both |calback| and |engine| must remain valid until stream is destroyed.
- */
-CRONET_EXPORT
-cronet_bidirectional_stream* cronet_bidirectional_stream_create(
-    cronet_engine* engine,
-    void* annotation,
-    cronet_bidirectional_stream_callback* callback);
-
-/* TBD: The following methods return int. Should it be a custom type? */
-
-/* Destroys stream object. Destroy could be called from any thread, including
- * network thread, but is posted, so |stream| is valid until calling task is
- * complete.
- */
-CRONET_EXPORT
-int cronet_bidirectional_stream_destroy(cronet_bidirectional_stream* stream);
-
-/**
- * Disables or enables auto flush. By default, data is flushed after
- * every cronet_bidirectional_stream_write(). If the auto flush is disabled,
- * the client should explicitly call cronet_bidirectional_stream_flush to flush
- * the data.
- */
-CRONET_EXPORT void cronet_bidirectional_stream_disable_auto_flush(
-    cronet_bidirectional_stream* stream,
-    bool disable_auto_flush);
-
-/**
- * Delays sending request headers until cronet_bidirectional_stream_flush()
- * is called. This flag is currently only respected when QUIC is negotiated.
- * When true, QUIC will send request header frame along with data frame(s)
- * as a single packet when possible.
- */
-CRONET_EXPORT
-void cronet_bidirectional_stream_delay_request_headers_until_flush(
-    cronet_bidirectional_stream* stream,
-    bool delay_headers_until_flush);
-
-/* Starts the stream by sending request to |url| using |method| and |headers|.
- * If |end_of_stream| is true, then no data is expected to be written. The
- * |method| is HTTP verb, with PUT having a special meaning to mark idempotent
- * request, which could use QUIC 0-RTT.
- */
-CRONET_EXPORT
-int cronet_bidirectional_stream_start(
-    cronet_bidirectional_stream* stream,
-    const char* url,
-    int priority,
-    const char* method,
-    const cronet_bidirectional_stream_header_array* headers,
-    bool end_of_stream);
-
-/* Reads response data into |buffer| of |capacity| length. Must only be called
- * at most once in response to each invocation of the
- * on_stream_ready()/on_response_headers_received() and on_read_completed()
- * methods of the cronet_bidirectional_stream_callback.
- * Each call will result in an invocation of the callback's
- * on_read_completed() method if data is read, or its on_failed() method if
- * there's an error. The callback's on_succeeded() method is also invoked if
- * there is no more data to read and |end_of_stream| was previously sent.
- */
-CRONET_EXPORT
-int cronet_bidirectional_stream_read(cronet_bidirectional_stream* stream,
-                                     char* buffer,
-                                     int capacity);
-
-/* Writes request data from |buffer| of |buffer_length| length. If auto flush is
- * disabled, data will be sent only after cronet_bidirectional_stream_flush() is
- * called.
- * Each call will result in an invocation the callback's on_write_completed()
- * method if data is sent, or its on_failed() method if there's an error.
- * The callback's on_succeeded() method is also invoked if |end_of_stream| is
- * set and all response data has been read.
- */
-CRONET_EXPORT
-int cronet_bidirectional_stream_write(cronet_bidirectional_stream* stream,
-                                      const char* buffer,
-                                      int buffer_length,
-                                      bool end_of_stream);
-
-/**
- * Flushes pending writes. This method should not be called before invocation of
- * on_stream_ready() method of the cronet_bidirectional_stream_callback.
- * For each previously called cronet_bidirectional_stream_write()
- * a corresponding on_write_completed() callback will be invoked when the buffer
- * is sent.
- */
-CRONET_EXPORT
-void cronet_bidirectional_stream_flush(cronet_bidirectional_stream* stream);
-
-/* Cancels the stream. Can be called at any time after
- * cronet_bidirectional_stream_start(). The on_canceled() method of
- * cronet_bidirectional_stream_callback will be invoked when cancelation
- * is complete and no further callback methods will be invoked. If the
- * stream has completed or has not started, calling
- * cronet_bidirectional_stream_cancel() has no effect and on_canceled() will not
- * be invoked. At most one callback method may be invoked after
- * cronet_bidirectional_stream_cancel() has completed.
- */
-CRONET_EXPORT
-void cronet_bidirectional_stream_cancel(cronet_bidirectional_stream* stream);
-
-/* Returns true if the |stream| was successfully started and is now done
- * (succeeded, canceled, or failed).
- * Returns false if the |stream| stream is not yet started or is in progress.
- */
-CRONET_EXPORT
-bool cronet_bidirectional_stream_is_done(cronet_bidirectional_stream* stream);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif  // COMPONENTS_CRONET_IOS_CRONET_C_FOR_GRPC_H_