Imported existing code

libraries/include/boost/asio/impl/read_at.ipp

@@ -0,0 +1,367 @@
+//
+// read_at.ipp
+// ~~~~~~~~~~~
+//
+// Copyright (c) 2003-2008 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_READ_AT_IPP
+#define BOOST_ASIO_READ_AT_IPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/push_options.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+#include <algorithm>
+#include <boost/asio/detail/pop_options.hpp>
+
+#include <boost/asio/buffer.hpp>
+#include <boost/asio/completion_condition.hpp>
+#include <boost/asio/error.hpp>
+#include <boost/asio/detail/bind_handler.hpp>
+#include <boost/asio/detail/consuming_buffers.hpp>
+#include <boost/asio/detail/handler_alloc_helpers.hpp>
+#include <boost/asio/detail/handler_invoke_helpers.hpp>
+#include <boost/asio/detail/throw_error.hpp>
+
+namespace boost {
+namespace asio {
+
+template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
+    typename CompletionCondition>
+std::size_t read_at(SyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, const MutableBufferSequence& buffers,
+    CompletionCondition completion_condition, boost::system::error_code& ec)
+{
+  ec = boost::system::error_code();
+  boost::asio::detail::consuming_buffers<
+    mutable_buffer, MutableBufferSequence> tmp(buffers);
+  std::size_t total_transferred = 0;
+  tmp.set_max_size(detail::adapt_completion_condition_result(
+        completion_condition(ec, total_transferred)));
+  while (tmp.begin() != tmp.end())
+  {
+    std::size_t bytes_transferred = d.read_some_at(
+        offset + total_transferred, tmp, ec);
+    tmp.consume(bytes_transferred);
+    total_transferred += bytes_transferred;
+    tmp.set_max_size(detail::adapt_completion_condition_result(
+          completion_condition(ec, total_transferred)));
+  }
+  return total_transferred;
+}
+
+template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence>
+inline std::size_t read_at(SyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, const MutableBufferSequence& buffers)
+{
+  boost::system::error_code ec;
+  std::size_t bytes_transferred = read_at(
+      d, offset, buffers, transfer_all(), ec);
+  boost::asio::detail::throw_error(ec);
+  return bytes_transferred;
+}
+
+template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
+    typename CompletionCondition>
+inline std::size_t read_at(SyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, const MutableBufferSequence& buffers,
+    CompletionCondition completion_condition)
+{
+  boost::system::error_code ec;
+  std::size_t bytes_transferred = read_at(
+      d, offset, buffers, completion_condition, ec);
+  boost::asio::detail::throw_error(ec);
+  return bytes_transferred;
+}
+
+template <typename SyncRandomAccessReadDevice, typename Allocator,
+    typename CompletionCondition>
+std::size_t read_at(SyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, boost::asio::basic_streambuf<Allocator>& b,
+    CompletionCondition completion_condition, boost::system::error_code& ec)
+{
+  std::size_t total_transferred = 0;
+  for (;;)
+  {
+    std::size_t bytes_available =
+      std::min<std::size_t>(512, b.max_size() - b.size());
+    std::size_t bytes_transferred = d.read_some_at(
+        offset + total_transferred, b.prepare(bytes_available), ec);
+    b.commit(bytes_transferred);
+    total_transferred += bytes_transferred;
+    if (b.size() == b.max_size()
+        || completion_condition(ec, total_transferred))
+      return total_transferred;
+  }
+}
+
+template <typename SyncRandomAccessReadDevice, typename Allocator>
+inline std::size_t read_at(SyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, boost::asio::basic_streambuf<Allocator>& b)
+{
+  boost::system::error_code ec;
+  std::size_t bytes_transferred = read_at(
+      d, offset, b, transfer_all(), ec);
+  boost::asio::detail::throw_error(ec);
+  return bytes_transferred;
+}
+
+template <typename SyncRandomAccessReadDevice, typename Allocator,
+    typename CompletionCondition>
+inline std::size_t read_at(SyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, boost::asio::basic_streambuf<Allocator>& b,
+    CompletionCondition completion_condition)
+{
+  boost::system::error_code ec;
+  std::size_t bytes_transferred = read_at(
+      d, offset, b, completion_condition, ec);
+  boost::asio::detail::throw_error(ec);
+  return bytes_transferred;
+}
+
+namespace detail
+{
+  template <typename AsyncRandomAccessReadDevice,
+      typename MutableBufferSequence, typename CompletionCondition,
+      typename ReadHandler>
+  class read_at_handler
+  {
+  public:
+    typedef boost::asio::detail::consuming_buffers<
+      mutable_buffer, MutableBufferSequence> buffers_type;
+
+    read_at_handler(AsyncRandomAccessReadDevice& stream,
+        boost::uint64_t offset, const buffers_type& buffers,
+        CompletionCondition completion_condition, ReadHandler handler)
+      : stream_(stream),
+        offset_(offset),
+        buffers_(buffers),
+        total_transferred_(0),
+        completion_condition_(completion_condition),
+        handler_(handler)
+    {
+    }
+
+    void operator()(const boost::system::error_code& ec,
+        std::size_t bytes_transferred)
+    {
+      total_transferred_ += bytes_transferred;
+      buffers_.consume(bytes_transferred);
+      buffers_.set_max_size(detail::adapt_completion_condition_result(
+            completion_condition_(ec, total_transferred_)));
+      if (buffers_.begin() == buffers_.end())
+      {
+        handler_(ec, total_transferred_);
+      }
+      else
+      {
+        stream_.async_read_some_at(
+            offset_ + total_transferred_, buffers_, *this);
+      }
+    }
+
+  //private:
+    AsyncRandomAccessReadDevice& stream_;
+    boost::uint64_t offset_;
+    buffers_type buffers_;
+    std::size_t total_transferred_;
+    CompletionCondition completion_condition_;
+    ReadHandler handler_;
+  };
+
+  template <typename AsyncRandomAccessReadDevice,
+      typename MutableBufferSequence, typename CompletionCondition,
+      typename ReadHandler>
+  inline void* asio_handler_allocate(std::size_t size,
+      read_at_handler<AsyncRandomAccessReadDevice, MutableBufferSequence,
+        CompletionCondition, ReadHandler>* this_handler)
+  {
+    return boost_asio_handler_alloc_helpers::allocate(
+        size, &this_handler->handler_);
+  }
+
+  template <typename AsyncRandomAccessReadDevice,
+      typename MutableBufferSequence, typename CompletionCondition,
+      typename ReadHandler>
+  inline void asio_handler_deallocate(void* pointer, std::size_t size,
+      read_at_handler<AsyncRandomAccessReadDevice, MutableBufferSequence,
+        CompletionCondition, ReadHandler>* this_handler)
+  {
+    boost_asio_handler_alloc_helpers::deallocate(
+        pointer, size, &this_handler->handler_);
+  }
+
+  template <typename Function, typename AsyncRandomAccessReadDevice,
+      typename MutableBufferSequence, typename CompletionCondition,
+      typename ReadHandler>
+  inline void asio_handler_invoke(const Function& function,
+      read_at_handler<AsyncRandomAccessReadDevice, MutableBufferSequence,
+        CompletionCondition, ReadHandler>* this_handler)
+  {
+    boost_asio_handler_invoke_helpers::invoke(
+        function, &this_handler->handler_);
+  }
+} // namespace detail
+
+template <typename AsyncRandomAccessReadDevice, typename MutableBufferSequence,
+    typename CompletionCondition, typename ReadHandler>
+inline void async_read_at(AsyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, const MutableBufferSequence& buffers,
+    CompletionCondition completion_condition, ReadHandler handler)
+{
+  boost::asio::detail::consuming_buffers<
+    mutable_buffer, MutableBufferSequence> tmp(buffers);
+
+  boost::system::error_code ec;
+  std::size_t total_transferred = 0;
+  tmp.set_max_size(detail::adapt_completion_condition_result(
+        completion_condition(ec, total_transferred)));
+  if (tmp.begin() == tmp.end())
+  {
+    d.get_io_service().post(detail::bind_handler(
+          handler, ec, total_transferred));
+    return;
+  }
+
+  d.async_read_some_at(offset, tmp,
+      detail::read_at_handler<AsyncRandomAccessReadDevice,
+        MutableBufferSequence, CompletionCondition, ReadHandler>(
+          d, offset, tmp, completion_condition, handler));
+}
+
+template <typename AsyncRandomAccessReadDevice, typename MutableBufferSequence,
+    typename ReadHandler>
+inline void async_read_at(AsyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, const MutableBufferSequence& buffers,
+    ReadHandler handler)
+{
+  async_read_at(d, offset, buffers, transfer_all(), handler);
+}
+
+namespace detail
+{
+  template <typename AsyncRandomAccessReadDevice, typename Allocator,
+      typename CompletionCondition, typename ReadHandler>
+  class read_at_streambuf_handler
+  {
+  public:
+    read_at_streambuf_handler(AsyncRandomAccessReadDevice& stream,
+        boost::uint64_t offset, basic_streambuf<Allocator>& streambuf,
+        CompletionCondition completion_condition, ReadHandler handler)
+      : stream_(stream),
+        offset_(offset),
+        streambuf_(streambuf),
+        total_transferred_(0),
+        completion_condition_(completion_condition),
+        handler_(handler)
+    {
+    }
+
+    void operator()(const boost::system::error_code& ec,
+        std::size_t bytes_transferred)
+    {
+      total_transferred_ += bytes_transferred;
+      streambuf_.commit(bytes_transferred);
+      std::size_t max_size = detail::adapt_completion_condition_result(
+            completion_condition_(ec, total_transferred_));
+      std::size_t bytes_available = std::min<std::size_t>(512,
+          std::min<std::size_t>(max_size,
+            streambuf_.max_size() - streambuf_.size()));
+      if (bytes_available == 0)
+      {
+        handler_(ec, total_transferred_);
+      }
+      else
+      {
+        stream_.async_read_some_at(offset_ + total_transferred_,
+            streambuf_.prepare(bytes_available), *this);
+      }
+    }
+
+  //private:
+    AsyncRandomAccessReadDevice& stream_;
+    boost::uint64_t offset_;
+    boost::asio::basic_streambuf<Allocator>& streambuf_;
+    std::size_t total_transferred_;
+    CompletionCondition completion_condition_;
+    ReadHandler handler_;
+  };
+
+  template <typename AsyncRandomAccessReadDevice, typename Allocator,
+      typename CompletionCondition, typename ReadHandler>
+  inline void* asio_handler_allocate(std::size_t size,
+      read_at_streambuf_handler<AsyncRandomAccessReadDevice, Allocator,
+        CompletionCondition, ReadHandler>* this_handler)
+  {
+    return boost_asio_handler_alloc_helpers::allocate(
+        size, &this_handler->handler_);
+  }
+
+  template <typename AsyncRandomAccessReadDevice, typename Allocator,
+      typename CompletionCondition, typename ReadHandler>
+  inline void asio_handler_deallocate(void* pointer, std::size_t size,
+      read_at_streambuf_handler<AsyncRandomAccessReadDevice, Allocator,
+        CompletionCondition, ReadHandler>* this_handler)
+  {
+    boost_asio_handler_alloc_helpers::deallocate(
+        pointer, size, &this_handler->handler_);
+  }
+
+  template <typename Function, typename AsyncRandomAccessReadDevice,
+      typename Allocator, typename CompletionCondition, typename ReadHandler>
+  inline void asio_handler_invoke(const Function& function,
+      read_at_streambuf_handler<AsyncRandomAccessReadDevice, Allocator,
+        CompletionCondition, ReadHandler>* this_handler)
+  {
+    boost_asio_handler_invoke_helpers::invoke(
+        function, &this_handler->handler_);
+  }
+} // namespace detail
+
+template <typename AsyncRandomAccessReadDevice, typename Allocator,
+    typename CompletionCondition, typename ReadHandler>
+inline void async_read_at(AsyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, boost::asio::basic_streambuf<Allocator>& b,
+    CompletionCondition completion_condition, ReadHandler handler)
+{
+  boost::system::error_code ec;
+  std::size_t total_transferred = 0;
+  std::size_t max_size = detail::adapt_completion_condition_result(
+        completion_condition(ec, total_transferred));
+  std::size_t bytes_available = std::min<std::size_t>(512,
+      std::min<std::size_t>(max_size, b.max_size() - b.size()));
+  if (bytes_available == 0)
+  {
+    d.get_io_service().post(detail::bind_handler(
+          handler, ec, total_transferred));
+    return;
+  }
+
+  d.async_read_some_at(offset, b.prepare(bytes_available),
+      detail::read_at_streambuf_handler<AsyncRandomAccessReadDevice, Allocator,
+        CompletionCondition, ReadHandler>(
+          d, offset, b, completion_condition, handler));
+}
+
+template <typename AsyncRandomAccessReadDevice, typename Allocator,
+    typename ReadHandler>
+inline void async_read_at(AsyncRandomAccessReadDevice& d,
+    boost::uint64_t offset, boost::asio::basic_streambuf<Allocator>& b,
+    ReadHandler handler)
+{
+  async_read_at(d, offset, b, transfer_all(), handler);
+}
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_READ_AT_IPP