build: Fix NetBSD build issues

* Use LITTLE_ENDIAN instead of __LITTLE_ENDIAN (LITTLE_ENDIAN is what
  POSIX now specifies and everyone seems to define - NetBSD also
  defines _LITTLE_ENDIAN, but not __LITTLE_ENDIAN)

* file descriptors greater than 2 must be explicitly passed to a child
  on NetBSD. POSIX leaves that unspecified, see
  https://pubs.opengroup.org/onlinepubs/9799919799/utilities/V3_chap02.html#exec

* system library functions get declared with visibility "default" on
  NetBSD, so a "hidden" visibility attribute is ignored on a
  redeclaration. Work around by putting the functions in a namespace -
  as they are extern "C", they still end up in the object file without
  the namespace qualifier.

* remove the cast on the NULL pointer on the funopen call - it's not
  needed and the types are different between FreeBSD (fpos_t) and
  NetBSD/OpenBSD (off_t); also trying to change that upstream
  https://github.com/openSUSE/libsolv/pull/603

Change-Id: I6ab7f3c74d18960d7589b403a1c219cdac85a453
Reviewed-on: https://review.haiku-os.org/c/haiku/+/10133
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: Adrien Destugues <[email protected]>

build/scripts/build_haiku_image

@@ -112,7 +112,7 @@ elif [ $isImage ]; then
 
 		fsShellCommandWrapper()
 		{
-			$actualFSShellCommand 5>&- 6>&- "$@"
+			$actualFSShellCommand 3<&3 4>&4 5>&- 6>&- "$@"
 		}
 
 		bfsShellWrapper()

headers/os/support/ByteOrder.h

@@ -30,7 +30,7 @@ typedef enum {
 #define B_SWAP_INT32(arg)    __swap_int32(arg)
 #define B_SWAP_INT16(arg)    __swap_int16(arg)
 
-#if BYTE_ORDER == __LITTLE_ENDIAN
+#if BYTE_ORDER == LITTLE_ENDIAN
 /* Host is little endian */
 
 #define B_HOST_IS_LENDIAN 1

headers/private/fs_shell/fssh_byte_order.h

@@ -37,7 +37,7 @@ typedef enum {
 #define FSSH_B_SWAP_INT32(arg)    __fssh_swap_int32(arg)
 #define FSSH_B_SWAP_INT16(arg)    __fssh_swap_int16(arg)
 
-#if BYTE_ORDER == __LITTLE_ENDIAN
+#if BYTE_ORDER == LITTLE_ENDIAN
 // Host is little endian
 
 #define FSSH_B_HOST_IS_LENDIAN 1

src/build/libroot/function_remapper.cpp

@@ -11,6 +11,15 @@
 
 #include "remapped_functions.h"
 
+#if defined(__NetBSD__)
+/* NetBSD explicitly sets the visibility to "default" when declaring public
+   functions, so any visibility attribute on a redeclaration is
+   ignored. However, we can work around this by placing the
+   declarations in a namespace. Since we are dealing with extern "C"
+   declarations, there is no name mangling. */
+namespace hidden_functions
+{
+#endif
 
 extern "C" int HIDDEN_FUNCTION_ATTRIBUTE
 fchmod(int fd, mode_t mode)
@@ -387,3 +396,7 @@ fs_stat_attr(int fd, const char *attribute, struct attr_info *attrInfo)
 }
 
 #endif // defined(HAIKU_HOST_USE_XATTR) && defined(HAIKU_HOST_PLATFORM_HAIKU)
+
+#if defined(__NetBSD__)
+}
+#endif

src/libs/libsolv/ext/solv_xfopen.c

@@ -28,7 +28,7 @@ static FILE *cookieopen(void *cookie, const char *mode,
   return funopen(cookie, 
       (int (*)(void *, char *, int))(*mode == 'r' ? cread : NULL),		/* readfn */
       (int (*)(void *, const char *, int))(*mode == 'w' ? cwrite : NULL),	/* writefn */
-      (fpos_t (*)(void *, fpos_t, int))NULL,					/* seekfn */
+      NULL,									/* seekfn */
       cclose
       );
 #elif defined(HAVE_FOPENCOOKIE)