Fix bugs in unix ffi usage

basis/io/backend/unix/multiplexers/select/select.factor

@@ -3,7 +3,7 @@
 USING: alien.data kernel bit-arrays sequences assocs math
 namespaces accessors math.order locals fry io.ports
 io.backend.unix io.backend.unix.multiplexers unix unix.ffi
-unix.time ;
+unix.time layouts ;
 IN: io.backend.unix.multiplexers.select
 
 TUPLE: select-mx < mx read-fdset write-fdset ;
@@ -12,7 +12,9 @@ TUPLE: select-mx < mx read-fdset write-fdset ;
 ! FD_SET to be an array of cells, so we have to account for
 ! byte order differences on big endian platforms
 : munge ( i -- i' )
-    little-endian? [ BIN: 11000 bitxor ] unless ; inline
+    little-endian? [
+      cell 4 = [ BIN: 11000 ] [ BIN: 111000 ] if
+      bitxor ] unless ; inline
 
 : <select-mx> ( -- mx )
     select-mx new-mx

basis/io/backend/unix/unix.factor

@@ -146,7 +146,7 @@ M: stdin dispose*
 
 : wait-for-stdin ( stdin -- size )
     [ control>> CHAR: X over io:stream-write1 io:stream-flush ]
-    [ size>> ssize_t heap-size swap io:stream-read int deref ]
+    [ size>> ssize_t heap-size swap io:stream-read ssize_t deref ]
     bi ;
 
 :: refill-stdin ( buffer stdin size -- )

basis/io/directories/unix/unix.factor

@@ -5,7 +5,7 @@ combinators continuations destructors fry io io.backend
 io.backend.unix io.directories io.encodings.binary
 io.encodings.utf8 io.files io.pathnames io.files.types kernel
 math.bitwise sequences system unix unix.stat vocabs.loader
-classes.struct unix.ffi literals ;
+classes.struct unix.ffi literals libc ;
 IN: io.directories.unix
 
 CONSTANT: touch-mode flags{ O_WRONLY O_APPEND O_CREAT O_EXCL }
@@ -39,7 +39,8 @@ HOOK: find-next-file os ( DIR* -- byte-array )
 M: unix find-next-file ( DIR* -- byte-array )
     dirent <struct>
     f void* <ref>
-    [ readdir_r 0 = [ (io-error) ] unless ] 2keep
+    0 set-errno
+    [ readdir_r 0 = [ errno 0 = [ (io-error) ] unless ] unless ] 2keep
     void* deref [ drop f ] unless ;
 
 : dirent-type>file-type ( ch -- type )