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/*
* mmap.c
*/
#include <stdint.h>
#include <errno.h>
#include <sys/syscall.h>
#include <sys/mman.h>
#include <unistd.h>
#include <bitsize.h>
#include <klibc/sysconfig.h>
/*
* Set in SYSCALLS whether or not we should use an unadorned mmap() system
* call (typical on 64-bit architectures).
*/
#if _KLIBC_USE_MMAP2
/* This architecture uses mmap2(). The Linux mmap2() system call takes
a page offset as the offset argument. We need to make sure we have
the proper conversion in place. */
extern void *__mmap2(void *, size_t, int, int, int, size_t);
void *mmap(void *start, size_t length, int prot, int flags, int fd,
off_t offset)
{
const int mmap2_shift = _KLIBC_MMAP2_SHIFT;
const off_t mmap2_mask = ((off_t) 1 << mmap2_shift) - 1;
if (offset & mmap2_mask) {
errno = EINVAL;
return MAP_FAILED;
}
return __mmap2(start, length, prot, flags, fd,
(size_t) offset >> mmap2_shift);
}
#endif
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