12 #define CHECK(x) !(x) ? abort() : 0
14 /* Define __UNUSED__ that also other compilers than gcc can run the tests. */
17 #define __UNUSED__ __attribute__((__unused__))
22 /* Prefer MAP_ANON(YMOUS) to /dev/zero, since we don't need to keep a
25 # undef HAVE_MMAP_DEV_ZERO
27 # include <sys/mman.h>
29 # define MAP_FAILED -1
31 # if !defined (MAP_ANONYMOUS) && defined (MAP_ANON)
32 # define MAP_ANONYMOUS MAP_ANON
38 #ifdef HAVE_MMAP_DEV_ZERO
40 # include <sys/mman.h>
42 # define MAP_FAILED -1
50 allocate_mmap (size_t size)
53 #if defined (HAVE_MMAP_DEV_ZERO)
54 static int dev_zero_fd = -1;
57 #ifdef HAVE_MMAP_DEV_ZERO
58 if (dev_zero_fd == -1)
60 dev_zero_fd = open ("/dev/zero", O_RDONLY);
61 if (dev_zero_fd == -1)
63 perror ("open /dev/zero: %m");
71 page = mmap (NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
72 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
74 #ifdef HAVE_MMAP_DEV_ZERO
75 page = mmap (NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
76 MAP_PRIVATE, dev_zero_fd, 0);
79 if (page == (void *) MAP_FAILED)
81 perror ("virtual memory exhausted");