1 | /* |
2 | * Copyright 2016-present Facebook, Inc. |
3 | * |
4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
5 | * you may not use this file except in compliance with the License. |
6 | * You may obtain a copy of the License at |
7 | * |
8 | * http://www.apache.org/licenses/LICENSE-2.0 |
9 | * |
10 | * Unless required by applicable law or agreed to in writing, software |
11 | * distributed under the License is distributed on an "AS IS" BASIS, |
12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
13 | * See the License for the specific language governing permissions and |
14 | * limitations under the License. |
15 | */ |
16 | |
17 | #pragma once |
18 | |
19 | #include <folly/portability/Config.h> |
20 | #include <folly/portability/IOVec.h> |
21 | #include <folly/portability/SysTypes.h> |
22 | |
23 | #if !FOLLY_HAVE_PREADV |
24 | extern "C" ssize_t preadv(int fd, const iovec* iov, int count, off_t offset); |
25 | #endif |
26 | #if !FOLLY_HAVE_PWRITEV |
27 | extern "C" ssize_t pwritev(int fd, const iovec* iov, int count, off_t offset); |
28 | #endif |
29 | |
30 | #ifdef _WIN32 |
31 | extern "C" ssize_t readv(int fd, const iovec* iov, int count); |
32 | extern "C" ssize_t writev(int fd, const iovec* iov, int count); |
33 | #endif |
34 | |
35 | namespace folly { |
36 | #ifdef IOV_MAX // not defined on Android |
37 | constexpr size_t kIovMax = IOV_MAX; |
38 | #else |
39 | constexpr size_t kIovMax = UIO_MAXIOV; |
40 | #endif |
41 | } // namespace folly |
42 | |