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/*
* Copyright 2015 Vincent Sanders <vince@netsurf-browser.org>
*
* This file is part of libnsutils.
*
* Licensed under the MIT License,
* http://www.opensource.org/licenses/mit-license.php
*/
/**
* \file
* unistd style operations.
*/
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include "nsutils/unistd.h"
/* exported interface documented in nsutils/unistd.h */
ssize_t nsu_pwrite(int fd, const void *buf, size_t count, off_t offset)
{
#if (defined(__riscos) || defined(__amiga) || defined(_WIN32) || defined(__serenity__))
off_t sk;
sk = lseek(fd, offset, SEEK_SET);
if (sk == (off_t)-1) {
#if defined(__amiga)
/* amigaos cannot seek past the end of the existing file so use
* ftruncate to make the file long enough and retry the seek.
*/
int ret;
if (errno == ESPIPE) {
ret = ftruncate(fd, offset);
if (ret == -1) {
return -1;
}
sk = lseek(fd, offset, SEEK_SET);
if (sk == (off_t)-1) {
return -1;
}
} else
#endif
return -1;
}
return write(fd, buf, count);
#else
return pwrite(fd, buf, count, offset);
#endif
}
/* exported interface documented in nsutils/unistd.h */
ssize_t nsu_pread(int fd, void *buf, size_t count, off_t offset)
{
#if (defined(__riscos) || defined(_WIN32) || defined(__serenity__) || (defined(__amiga) && !defined(__amigaos4__)))
off_t sk;
sk = lseek(fd, offset, SEEK_SET);
if (sk == -1) {
return (off_t)-1;
}
return read(fd, buf, count);
#else
return pread(fd, buf, count, offset);
#endif
}
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