helpers.c

#include <errno.h>

#include "helpers.h"

#ifndef CONFIG_LINUX_FALLOCATE
int fallocate(int fd, int mode, off_t offset, off_t len)
{
	errno = ENOSYS;
	return -1;
}
#endif

#ifndef CONFIG_POSIX_FALLOCATE
int posix_fallocate(int fd, off_t offset, off_t len)
{
	return 0;
}
#endif

#ifndef CONFIG_SYNC_FILE_RANGE
int sync_file_range(int fd, uint64_t offset, uint64_t nbytes,
		    unsigned int flags)
{
	errno = ENOSYS;
	return -1;
}
#endif

#if defined (__APPLE__)
int posix_fadvise(int fd, off_t offset, off_t len, int advice)
{
	if (advice == POSIX_FADV_DONTNEED)
		return discard_pages(fd, offset, len);
        errno = EINVAL; 
	return -1;
}
#else
#ifndef CONFIG_POSIX_FADVISE
int posix_fadvise(int fd, off_t offset, off_t len, int advice)
{
	return 0;
}
#endif
#endif /* defined (__APPLE__) */