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/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
*
* 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 OWNER 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 <sys/uio.h>
// System calls we need.
extern "C" int __preadv64(int, const struct iovec*, int, long, long);
extern "C" int __preadv64v2(int, const struct iovec*, int, long, long, int);
extern "C" int __pwritev64(int, const struct iovec*, int, long, long);
extern "C" int __pwritev64v2(int, const struct iovec*, int, long, long, int);
// There is no 32-bit off_t preadv/pwritev (even on LP32).
// To avoid 32-bit ABI issues about which register pairs you're allowed
// to pass 64-bit values in, the kernel just takes two `long` arguments --
// which are int32_t for LP32, remember -- and stitches them together.
// It even does this for LP64, taking a second unused always-zero `long`.
// (The first long was int64_t, which is the same as off64_t.)
// The pair is split lo-hi (not hi-lo, as llseek is).
ssize_t preadv(int fd, const struct iovec* ios, int count, off_t offset) {
return preadv64(fd, ios, count, offset);
}
ssize_t preadv64(int fd, const struct iovec* ios, int count, off64_t offset) {
#if defined(__LP64__)
return __preadv64(fd, ios, count, offset, 0);
#else
return __preadv64(fd, ios, count, offset, offset >> 32);
#endif
}
ssize_t pwritev(int fd, const struct iovec* ios, int count, off_t offset) {
return pwritev64(fd, ios, count, offset);
}
ssize_t pwritev64(int fd, const struct iovec* ios, int count, off64_t offset) {
#if defined(__LP64__)
return __pwritev64(fd, ios, count, offset, 0);
#else
return __pwritev64(fd, ios, count, offset, offset >> 32);
#endif
}
ssize_t preadv2(int fd, const struct iovec* ios, int count, off_t offset, int flags) {
return preadv64v2(fd, ios, count, offset, flags);
}
ssize_t preadv64v2(int fd, const struct iovec* ios, int count, off64_t offset, int flags) {
#if defined(__LP64__)
return __preadv64v2(fd, ios, count, offset, 0, flags);
#else
return __preadv64v2(fd, ios, count, offset, offset >> 32, flags);
#endif
}
ssize_t pwritev2(int fd, const struct iovec* ios, int count, off_t offset, int flags) {
return pwritev64v2(fd, ios, count, offset, flags);
}
ssize_t pwritev64v2(int fd, const struct iovec* ios, int count, off64_t offset, int flags) {
#if defined(__LP64__)
return __pwritev64v2(fd, ios, count, offset, 0, flags);
#else
return __pwritev64v2(fd, ios, count, offset, offset >> 32, flags);
#endif
}
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