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Diffstat (limited to 'host/include/uhd/transport/zero_copy.hpp')
| -rw-r--r-- | host/include/uhd/transport/zero_copy.hpp | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/host/include/uhd/transport/zero_copy.hpp b/host/include/uhd/transport/zero_copy.hpp new file mode 100644 index 000000000..f80c738aa --- /dev/null +++ b/host/include/uhd/transport/zero_copy.hpp @@ -0,0 +1,184 @@ +// +// Copyright 2010-2011 Ettus Research LLC +// +// This program is free software: you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program. If not, see <http://www.gnu.org/licenses/>. +// + +#ifndef INCLUDED_UHD_TRANSPORT_ZERO_COPY_HPP +#define INCLUDED_UHD_TRANSPORT_ZERO_COPY_HPP + +#include <uhd/config.hpp> +#include <boost/utility.hpp> +#include <boost/shared_ptr.hpp> +#include <boost/intrusive_ptr.hpp> + +namespace uhd{ namespace transport{ + + //! Create smart pointer to a reusable managed buffer + template <typename T> UHD_INLINE boost::intrusive_ptr<T> make_managed_buffer(T *p){ + p->_ref_count = 1; //reset the count to 1 reference + return boost::intrusive_ptr<T>(p, false); + } + + /*! + * A managed receive buffer: + * Contains a reference to transport-managed memory, + * and a method to release the memory after reading. + */ + class UHD_API managed_recv_buffer{ + public: + typedef boost::intrusive_ptr<managed_recv_buffer> sptr; + + /*! + * Signal to the transport that we are done with the buffer. + * This should be called to release the buffer to the transport object. + * After calling, the referenced memory should be considered invalid. + */ + virtual void release(void) = 0; + + /*! + * Get a pointer to the underlying buffer. + * \return a pointer into memory + */ + template <class T> inline T cast(void) const{ + return static_cast<T>(this->get_buff()); + } + + /*! + * Get the size of the underlying buffer. + * \return the number of bytes + */ + inline size_t size(void) const{ + return this->get_size(); + } + + private: + virtual const void *get_buff(void) const = 0; + virtual size_t get_size(void) const = 0; + + public: int _ref_count; + }; + + UHD_INLINE void intrusive_ptr_add_ref(managed_recv_buffer *p){ + ++(p->_ref_count); + } + + UHD_INLINE void intrusive_ptr_release(managed_recv_buffer *p){ + if (--(p->_ref_count) == 0) p->release(); + } + + /*! + * A managed send buffer: + * Contains a reference to transport-managed memory, + * and a method to commit the memory after writing. + */ + class UHD_API managed_send_buffer{ + public: + typedef boost::intrusive_ptr<managed_send_buffer> sptr; + + /*! + * Signal to the transport that we are done with the buffer. + * This should be called to commit the write to the transport object. + * After calling, the referenced memory should be considered invalid. + * \param num_bytes the number of bytes written into the buffer + */ + virtual void commit(size_t num_bytes) = 0; + + /*! + * Get a pointer to the underlying buffer. + * \return a pointer into memory + */ + template <class T> inline T cast(void) const{ + return static_cast<T>(this->get_buff()); + } + + /*! + * Get the size of the underlying buffer. + * \return the number of bytes + */ + inline size_t size(void) const{ + return this->get_size(); + } + + private: + virtual void *get_buff(void) const = 0; + virtual size_t get_size(void) const = 0; + + public: int _ref_count; + }; + + UHD_INLINE void intrusive_ptr_add_ref(managed_send_buffer *p){ + ++(p->_ref_count); + } + + UHD_INLINE void intrusive_ptr_release(managed_send_buffer *p){ + if (--(p->_ref_count) == 0) p->commit(0); + } + + /*! + * A zero-copy interface for transport objects. + * Provides a way to get send and receive buffers + * with memory managed by the transport object. + */ + class UHD_API zero_copy_if : boost::noncopyable{ + public: + typedef boost::shared_ptr<zero_copy_if> sptr; + + /*! + * Get a new receive buffer from this transport object. + * \param timeout the timeout to get the buffer in seconds + * \return a managed buffer, or null sptr on timeout/error + */ + virtual managed_recv_buffer::sptr get_recv_buff(double timeout = 0.1) = 0; + + /*! + * Get the number of receive frames: + * The number of simultaneous receive buffers in use. + * \return number of frames + */ + virtual size_t get_num_recv_frames(void) const = 0; + + /*! + * Get the size of a receive frame: + * The maximum capacity of a single receive buffer. + * \return frame size in bytes + */ + virtual size_t get_recv_frame_size(void) const = 0; + + /*! + * Get a new send buffer from this transport object. + * \param timeout the timeout to get the buffer in seconds + * \return a managed buffer, or null sptr on timeout/error + */ + virtual managed_send_buffer::sptr get_send_buff(double timeout = 0.1) = 0; + + /*! + * Get the number of send frames: + * The number of simultaneous send buffers in use. + * \return number of frames + */ + virtual size_t get_num_send_frames(void) const = 0; + + /*! + * Get the size of a send frame: + * The maximum capacity of a single send buffer. + * \return frame size in bytes + */ + virtual size_t get_send_frame_size(void) const = 0; + + }; + +}} //namespace + +#endif /* INCLUDED_UHD_TRANSPORT_ZERO_COPY_HPP */ |