ffi: provide mmap through carray.

* configure: configure test for mmap depositing HAVE_MMAP into
config.h.

* ffi.c (struct carray): Subject to HAVE_MMAP, new mm_len
member which keeps track of the size of an underlying mapping
so that we can unmap it, as well as peform operations like
msync on it.
(make_carray): Initialize mm_len to 0.
(MAP_GROWSDOWN, MAP_LOCKED, MAP_NORESERVE, MAP_POPULATE,
MAP_NONBLOCK, MAP_STACK, MAP_HUGETLB, MAP_SHARED, MAP_PRIVATE,
MAP_FIXED, MAP_ANON, MAP_HUGE_SHIFT, MAP_HUGE_MASK, PROT_READ,
PROT_WRITE, PROT_EXEC, PROT_NONE, PROT_GROWSDOWN,
PROT_GROWSUP, MADV_NORMAL, MADV_RANDOM, MADV_SEQUENTIAL,
MADV_WILLNEED, MADV_DONTNEED, MADV_FREE, MADV_REMOVE,
MADV_DONTFORK, MADV_DOFORK, MADV_MERGEABLE, MADV_UNMERGEABLE,
MADV_HUGEPAGE, MADV_NOHUGEPAGE, MADV_DONTDUMP, MADV_DODUMP,
MADV_WIPEONFORK, MADV_KEEPONFORK, MADV_HWPOISON, MS_ASYNC,
MS_SYNC, MS_INVALIDATE): #define as 0 if missing.

(carray_munmap_op): New static function.
(carray_mmap_ops): New static structure.
(mmap_wrap, munmap_wrap): New functions.
(mmap_op): New static function.
(mprotect_wrap, madvise_wrap, msync_wrap): New functions.
(ffi_init): Register mmap, munmap, mprotect, madvise and msync
as well as numerous integer variables: map-growsdown,
map-locked, map-noreserve, map-populate, map-nonblock,
map-stack, map-hugetlb, map-shared, map-private, map-fixed,
map-anon, map-huge-shift, map-huge-mask, prot-read,
prot-write, prot-exec, prot-none, prot-growsdown,
prot-growsup, madv-normal, madv-random, madv-sequential,
madv-willneed, madv-dontneed, madv-free, madv-remove,
madv-dontfork, madv-dofork, madv-mergeable, madv-unmergeable,
madv-hugepage, madv-nohugepage, madv-dontdump, madv-dodump,
madv-wipeonfork, madv-keeponfork, madv-hwpoison, ms-async,
ms-sync, ms-invalidate, page-size.

* ffi.h (mmap_wrap, munmap_wrap, mprotect_wrap madvise_wrap,
msync_wrap): Declared.

* tests/017/mmap.tl: New file.

* txr.1: Documented.

* stdlib/doc-syms.tl: Updated.

1 files changed, 8 insertions, 0 deletions

diff --git a/ffi.h b/ffi.h
index a0adb0e0..fbc9faad 100644
--- a/ffi.h
+++ b/ffi.h
@@ -129,6 +129,14 @@ val uint_carray(val carray);
 val int_carray(val carray);
 val put_carray(val carray, val offs, val stream);
 val fill_carray(val carray, val offs, val stream);
+#if HAVE_MMAP
+val mmap_wrap(val type, val len, val prot, val flags,
+              val source_opt, val offset_opt, val addr_opt);
+val munmap_wrap(val carray);
+val mprotect_wrap(val carray, val prot, val offset, val size);
+val madvise_wrap(val carray, val advice, val offset, val size);
+val msync_wrap(val carray, val flags, val offset, val size);
+#endif
 mem_t *union_get_ptr(val self, val uni);
 val make_union(val type, val init, val memb);
 val union_members(val uni);