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authorJörg Frings-Fürst <debian@jff-webhosting.net>2020-02-02 17:14:32 +0100
committerJörg Frings-Fürst <debian@jff-webhosting.net>2020-02-02 17:14:32 +0100
commit5dadc28ea784db1ba1f56c2ea8618d2db67af1c8 (patch)
tree808b2499b54563b3290f34d70d159b1024310873 /backend/genesys/buffer.h
parent5bb4cf12855ec0151de15d6c5a2354ff08766957 (diff)
parent3dade5db2a37543f19f0967901d8d80a52a1e459 (diff)
Merge branch 'feature/upstream' into develop
Diffstat (limited to 'backend/genesys/buffer.h')
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1 files changed, 89 insertions, 0 deletions
diff --git a/backend/genesys/buffer.h b/backend/genesys/buffer.h
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+/* sane - Scanner Access Now Easy.
+
+ Copyright (C) 2019 Povilas Kanapickas <povilas@radix.lt>
+
+ This file is part of the SANE package.
+
+ 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 2 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, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ MA 02111-1307, USA.
+
+ As a special exception, the authors of SANE give permission for
+ additional uses of the libraries contained in this release of SANE.
+
+ The exception is that, if you link a SANE library with other files
+ to produce an executable, this does not by itself cause the
+ resulting executable to be covered by the GNU General Public
+ License. Your use of that executable is in no way restricted on
+ account of linking the SANE library code into it.
+
+ This exception does not, however, invalidate any other reasons why
+ the executable file might be covered by the GNU General Public
+ License.
+
+ If you submit changes to SANE to the maintainers to be included in
+ a subsequent release, you agree by submitting the changes that
+ those changes may be distributed with this exception intact.
+
+ If you write modifications of your own for SANE, it is your choice
+ whether to permit this exception to apply to your modifications.
+ If you do not wish that, delete this exception notice.
+*/
+
+#ifndef BACKEND_GENESYS_BUFFER_H
+#define BACKEND_GENESYS_BUFFER_H
+
+#include <vector>
+#include <cstddef>
+#include <cstdint>
+
+namespace genesys {
+
+/* A FIFO buffer. Note, that this is _not_ a ringbuffer.
+ if we need a block which does not fit at the end of our available data,
+ we move the available data to the beginning.
+*/
+struct Genesys_Buffer
+{
+ Genesys_Buffer() = default;
+
+ std::size_t size() const { return buffer_.size(); }
+ std::size_t avail() const { return avail_; }
+ std::size_t pos() const { return pos_; }
+
+ // TODO: refactor code that uses this function to no longer use it
+ void set_pos(std::size_t pos) { pos_ = pos; }
+
+ void alloc(std::size_t size);
+ void clear();
+
+ void reset();
+
+ std::uint8_t* get_write_pos(std::size_t size);
+ std::uint8_t* get_read_pos(); // TODO: mark as const
+
+ void produce(std::size_t size);
+ void consume(std::size_t size);
+
+private:
+ std::vector<std::uint8_t> buffer_;
+ // current position in read buffer
+ std::size_t pos_ = 0;
+ // data bytes currently in buffer
+ std::size_t avail_ = 0;
+};
+
+} // namespace genesys
+
+#endif // BACKEND_GENESYS_BUFFER_H