| /* |
| * nghttp2 - HTTP/2 C Library |
| * |
| * Copyright (c) 2014 Tatsuhiro Tsujikawa |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining |
| * a copy of this software and associated documentation files (the |
| * "Software"), to deal in the Software without restriction, including |
| * without limitation the rights to use, copy, modify, merge, publish, |
| * distribute, sublicense, and/or sell copies of the Software, and to |
| * permit persons to whom the Software is furnished to do so, subject to |
| * the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be |
| * included in all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
| * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
| * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
| * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| */ |
| #ifndef BUFFER_H |
| #define BUFFER_H |
| |
| #include "nghttp2_config.h" |
| |
| #include <cstring> |
| #include <algorithm> |
| #include <array> |
| |
| namespace nghttp2 { |
| |
| template <size_t N> struct Buffer { |
| Buffer() : pos(std::begin(buf)), last(pos) {} |
| // Returns the number of bytes to read. |
| size_t rleft() const { return last - pos; } |
| // Returns the number of bytes this buffer can store. |
| size_t wleft() const { return std::end(buf) - last; } |
| // Writes up to min(wleft(), |count|) bytes from buffer pointed by |
| // |src|. Returns number of bytes written. |
| size_t write(const void *src, size_t count) { |
| count = std::min(count, wleft()); |
| auto p = static_cast<const uint8_t *>(src); |
| last = std::copy_n(p, count, last); |
| return count; |
| } |
| size_t write(size_t count) { |
| count = std::min(count, wleft()); |
| last += count; |
| return count; |
| } |
| // Drains min(rleft(), |count|) bytes from start of the buffer. |
| size_t drain(size_t count) { |
| count = std::min(count, rleft()); |
| pos += count; |
| return count; |
| } |
| size_t drain_reset(size_t count) { |
| count = std::min(count, rleft()); |
| std::copy(pos + count, last, std::begin(buf)); |
| last = std::begin(buf) + (last - (pos + count)); |
| pos = std::begin(buf); |
| return count; |
| } |
| void reset() { pos = last = std::begin(buf); } |
| uint8_t *begin() { return std::begin(buf); } |
| uint8_t &operator[](size_t n) { return buf[n]; } |
| const uint8_t &operator[](size_t n) const { return buf[n]; } |
| std::array<uint8_t, N> buf; |
| uint8_t *pos, *last; |
| }; |
| |
| } // namespace nghttp2 |
| |
| #endif // BUFFER_H |