| /* |
| * Copyright (c) 2015, Intel Corporation |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without modification, |
| * are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, this |
| * list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation and/or |
| * other materials provided with the distribution. |
| * |
| * 3. Neither the name of the copyright holder nor the names of its contributors |
| * may be used to endorse or promote products derived from this software without |
| * specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR |
| * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON |
| * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "FullIo.hpp" |
| |
| #include <cerrno> |
| #include <unistd.h> |
| |
| namespace utility |
| { |
| |
| /** Workaround c++ `void *` arithmetic interdiction. */ |
| template <class Ptr> |
| Ptr *add(Ptr *ptr, size_t count) { |
| return (char *)ptr + count; |
| } |
| |
| template <class Buff> |
| static bool fullAccess(ssize_t (&accessor)(int, Buff, size_t), |
| bool (&accessFailed)(ssize_t), |
| int fd, Buff buf, size_t count) { |
| size_t done = 0; // Bytes already access in previous iterations |
| while (done < count) { |
| ssize_t accessed = accessor(fd, add(buf, done), count - done); |
| if (accessFailed(accessed)) { |
| return false; |
| } |
| done += accessed; |
| } |
| return true; |
| } |
| |
| static bool accessFailed(ssize_t accessRes) { |
| return accessRes == -1 and errno != EAGAIN and errno != EINTR; |
| } |
| |
| bool fullWrite(int fd, const void *buf, size_t count) { |
| return fullAccess(::write, accessFailed, fd, buf, count); |
| } |
| |
| static bool readFailed(ssize_t readRes) { |
| if (readRes == 0) { // read should not return 0 (EOF) |
| errno = 0; |
| return true; |
| } |
| return accessFailed(readRes); |
| } |
| bool fullRead(int fd, void *buf, size_t count) { |
| return fullAccess(::read, readFailed, fd, buf, count); |
| } |
| |
| } // namespace utility |
| |