Support sending a sliced file in chromium....

net/base/upload_data_stream.cc

 // Copyright (c) 2010 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.
 
 #include "net/base/upload_data_stream.h"
 
+#include "base/file_util.h"
 #include "base/logging.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 
 namespace net {
 
+UploadDataStream* UploadDataStream::Create(const UploadData* data,
+                                           int* error_code) {
+  scoped_ptr<UploadDataStream> stream(new UploadDataStream(data));
+  int rv = stream->FillBuf();
+  if (error_code)
+    *error_code = rv;
+  if (rv != OK)
+    return NULL;
+
+  return stream.release();
+}
+
 UploadDataStream::UploadDataStream(const UploadData* data)
     : data_(data),
       buf_(new IOBuffer(kBufSize)),
       buf_len_(0),
       next_element_(data->elements().begin()),
       next_element_offset_(0),
       next_element_remaining_(0),
       total_size_(data->GetContentLength()),
       current_position_(0),
       eof_(false) {
-  FillBuf();
 }
 
 UploadDataStream::~UploadDataStream() {
 }
 
 void UploadDataStream::DidConsume(size_t num_bytes) {
   DCHECK_LE(num_bytes, buf_len_);
   DCHECK(!eof_);
 
   buf_len_ -= num_bytes;
   if (buf_len_)
     memmove(buf_->data(), buf_->data() + num_bytes, buf_len_);
 
   FillBuf();
 
   current_position_ += num_bytes;
 }
 
-void UploadDataStream::FillBuf() {
+int UploadDataStream::FillBuf() {
   std::vector<UploadData::Element>::const_iterator end =
       data_->elements().end();
 
   while (buf_len_ < kBufSize && next_element_ != end) {
     bool advance_to_next_element = false;
 
     const UploadData::Element& element = *next_element_;
 
     size_t size_remaining = kBufSize - buf_len_;
     if (element.type() == UploadData::TYPE_BYTES) {
       const std::vector<char>& d = element.bytes();
       size_t count = d.size() - next_element_offset_;
 
       size_t bytes_copied = std::min(count, size_remaining);
 
       memcpy(buf_->data() + buf_len_, &d[next_element_offset_], bytes_copied);
       buf_len_ += bytes_copied;
 
       if (bytes_copied == count) {
         advance_to_next_element = true;
       } else {
         next_element_offset_ += bytes_copied;
       }
     } else {
       DCHECK(element.type() == UploadData::TYPE_FILE);
 
+      // If the underlying file has been changed, treat it as error.
+      // Note that the expected modification time from WebKit is based on
+      // time_t precision. So we have to convert both to time_t to compare.
+      if (!element.expected_file_modification_time().is_null()) {
+        file_util::FileInfo info;
+        if (file_util::GetFileInfo(element.file_path(), &info) &&
+            element.expected_file_modification_time().ToTimeT() !=
+                info.last_modified.ToTimeT()) {
+          return ERR_UPLOAD_FILE_CHANGED;
+        }
+      }
+
       if (!next_element_stream_.IsOpen()) {
         int flags = base::PLATFORM_FILE_OPEN |
                     base::PLATFORM_FILE_READ;
         int rv = next_element_stream_.Open(element.file_path(), flags);
         // If the file does not exist, that's technically okay.. we'll just
         // upload an empty file.  This is for consistency with Mozilla.
         DLOG_IF(WARNING, rv != OK) << "Failed to open \""
                                    << element.file_path().value()
                                    << "\" for reading: " << rv;
 
@@ skipping 24 matching lines @@
 
     if (advance_to_next_element) {
       ++next_element_;
       next_element_offset_ = 0;
       next_element_stream_.Close();
     }
   }
 
   if (next_element_ == end && !buf_len_)
     eof_ = true;
+
+  return OK;
 }
 
 }  // namespace net