Use CompletionOnceCallback in FtpTransaction.

Bug: 807724
Change-Id: I018eb874f2e9097dba9d8acdf58d6a18c569cc9d
Reviewed-on: https://chromium-review.googlesource.com/1100354Reviewed-by: Zhongyi Shi <zhongyi@chromium.org>
Commit-Queue: Bence Béky <bnc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#567988}

net/ftp/ftp_network_transaction.cc

@@ -15,6 +15,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "net/base/address_list.h"
+#include "net/base/completion_once_callback.h"
 #include "net/base/escape.h"
 #include "net/base/net_errors.h"
 #include "net/base/parse_number.h"
@@ -257,7 +258,7 @@ int FtpNetworkTransaction::Stop(int error) {
 
 int FtpNetworkTransaction::Start(
     const FtpRequestInfo* request_info,
-    const CompletionCallback& callback,
+    CompletionOnceCallback callback,
     const NetLogWithSource& net_log,
     const NetworkTrafficAnnotationTag& traffic_annotation) {
   net_log_ = net_log;
@@ -281,12 +282,12 @@ int FtpNetworkTransaction::Start(
   next_state_ = STATE_CTRL_RESOLVE_HOST;
   int rv = DoLoop(OK);
   if (rv == ERR_IO_PENDING)
-    user_callback_ = callback;
+    user_callback_ = std::move(callback);
   return rv;
 }
 
 int FtpNetworkTransaction::RestartWithAuth(const AuthCredentials& credentials,
-                                           const CompletionCallback& callback) {
+                                           CompletionOnceCallback callback) {
   ResetStateForRestart();
 
   credentials_ = credentials;
@@ -294,13 +295,13 @@ int FtpNetworkTransaction::RestartWithAuth(const AuthCredentials& credentials,
   next_state_ = STATE_CTRL_RESOLVE_HOST;
   int rv = DoLoop(OK);
   if (rv == ERR_IO_PENDING)
-    user_callback_ = callback;
+    user_callback_ = std::move(callback);
   return rv;
 }
 
 int FtpNetworkTransaction::Read(IOBuffer* buf,
                                 int buf_len,
-                                const CompletionCallback& callback) {
+                                CompletionOnceCallback callback) {
   DCHECK(buf);
   DCHECK_GT(buf_len, 0);
 
@@ -310,7 +311,7 @@ int FtpNetworkTransaction::Read(IOBuffer* buf,
   next_state_ = STATE_DATA_READ;
   int rv = DoLoop(OK);
   if (rv == ERR_IO_PENDING)
-    user_callback_ = callback;
+    user_callback_ = std::move(callback);
   return rv;
 }
 
@@ -372,10 +373,8 @@ void FtpNetworkTransaction::EstablishDataConnection(State state_after_connect) {
 
 void FtpNetworkTransaction::DoCallback(int rv) {
   DCHECK(rv != ERR_IO_PENDING);
-  DCHECK(!user_callback_.is_null());
 
-  // Since Run may result in Read being called, clear callback_ up front.
-  base::ResetAndReturn(&user_callback_).Run(rv);
+  std::move(user_callback_).Run(rv);
 }
 
 void FtpNetworkTransaction::OnIOComplete(int result) {

net/ftp/ftp_network_transaction.h

@@ -16,6 +16,7 @@
 #include "base/memory/ref_counted.h"
 #include "net/base/address_list.h"
 #include "net/base/auth.h"
+#include "net/base/completion_once_callback.h"
 #include "net/base/completion_repeating_callback.h"
 #include "net/base/net_export.h"
 #include "net/dns/host_resolver.h"
@@ -40,14 +41,14 @@ class NET_EXPORT_PRIVATE FtpNetworkTransaction : public FtpTransaction {
 
   // FtpTransaction methods:
   int Start(const FtpRequestInfo* request_info,
-            const CompletionCallback& callback,
+            CompletionOnceCallback callback,
             const NetLogWithSource& net_log,
             const NetworkTrafficAnnotationTag& traffic_annotation) override;
   int RestartWithAuth(const AuthCredentials& credentials,
-                      const CompletionCallback& callback) override;
+                      CompletionOnceCallback callback) override;
   int Read(IOBuffer* buf,
            int buf_len,
-           const CompletionCallback& callback) override;
+           CompletionOnceCallback callback) override;
   const FtpResponseInfo* GetResponseInfo() const override;
   LoadState GetLoadState() const override;
   uint64_t GetUploadProgress() const override;
@@ -203,7 +204,7 @@ class NET_EXPORT_PRIVATE FtpNetworkTransaction : public FtpTransaction {
   Command command_sent_;
 
   CompletionRepeatingCallback io_callback_;
-  CompletionCallback user_callback_;
+  CompletionOnceCallback user_callback_;
 
   NetLogWithSource net_log_;
   const FtpRequestInfo* request_;

net/ftp/ftp_transaction.h

@@ -7,7 +7,7 @@
 
 #include <stdint.h>
 
-#include "net/base/completion_callback.h"
+#include "net/base/completion_once_callback.h"
 #include "net/base/io_buffer.h"
 #include "net/base/load_states.h"
 #include "net/base/net_export.h"
@@ -30,10 +30,9 @@ class NET_EXPORT_PRIVATE FtpTransaction {
   //
   // Returns OK if the transaction could be started synchronously, which means
   // that the request was served from the cache (only supported for directory
-  // listings).  ERR_IO_PENDING is returned to indicate that the
-  // CompletionCallback will be notified once response info is available or if
-  // an IO error occurs.  Any other return value indicates that the transaction
-  // could not be started.
+  // listings).  ERR_IO_PENDING is returned to indicate that |callback| will be
+  // notified once response info is available or if an IO error occurs.  Any
+  // other return value indicates that the transaction could not be started.
   //
   // Regardless of the return value, the caller is expected to keep the
   // request_info object alive until Destroy is called on the transaction.
@@ -42,30 +41,29 @@ class NET_EXPORT_PRIVATE FtpTransaction {
   //
   // Profiling information for the request is saved to |net_log| if non-NULL.
   virtual int Start(const FtpRequestInfo* request_info,
-                    const CompletionCallback& callback,
+                    CompletionOnceCallback callback,
                     const NetLogWithSource& net_log,
                     const NetworkTrafficAnnotationTag& traffic_annotation) = 0;
 
   // Restarts the FTP transaction with authentication credentials.
   virtual int RestartWithAuth(const AuthCredentials& credentials,
-                              const CompletionCallback& callback) = 0;
+                              CompletionOnceCallback callback) = 0;
 
   // Once response info is available for the transaction, response data may be
   // read by calling this method.
   //
   // Response data is copied into the given buffer and the number of bytes
-  // copied is returned.  ERR_IO_PENDING is returned if response data is not
-  // yet available.  The CompletionCallback is notified when the data copy
-  // completes, and it is passed the number of bytes that were successfully
-  // copied.  Or, if a read error occurs, the CompletionCallback is notified of
-  // the error.  Any other negative return value indicates that the transaction
-  // could not be read.
+  // copied is returned.  ERR_IO_PENDING is returned if response data is not yet
+  // available.  |callback| is notified when the data copy completes, and it is
+  // passed the number of bytes that were successfully copied.  Or, if a read
+  // error occurs, |callback| is notified of the error.  Any other negative
+  // return value indicates that the transaction could not be read.
   //
   // NOTE: The transaction is not responsible for deleting the callback object.
   //
   virtual int Read(IOBuffer* buf,
                    int buf_len,
-                   const CompletionCallback& callback) = 0;
+                   CompletionOnceCallback callback) = 0;
 
   // Returns the response info for this transaction or NULL if the response
   // info is not available.