While 'd_type' is a non-standard extension to `struct dirent`, only
glibc signals its presence with a macro '_DIRENT_HAVE_D_TYPE'.
However, any platform with 'd_type' also includes a way to convert to
mode_t values using the macro 'DTTOIF', so we can check for that alone
and still be confident that the 'd_type' member exists.
(If this turns out to be wrong, I'll go back and set up an actual
CMake check.)
I couldn't think of how to write a test for this, because I couldn't
think of how to test that a 'stat' call doesn't happen without
controlling the filesystem or intercepting 'stat', and there's no good
cross-platform way to do that that I know of.
Follow-up (almost a year later) to r342089.
rdar://problem/
50592673
https://reviews.llvm.org/D64940
llvm-svn: 366486
static file_type direntType(dirent* Entry) {
// Most platforms provide the file type in the dirent: Linux/BSD/Mac.
// The DTTOIF macro lets us reuse our status -> type conversion.
-#if defined(_DIRENT_HAVE_D_TYPE) && defined(DTTOIF)
+ // Note that while glibc provides a macro to see if this is supported,
+ // _DIRENT_HAVE_D_TYPE, it's not defined on BSD/Mac, so we test for the
+ // d_type-to-mode_t conversion macro instead.
+#if defined(DTTOIF)
return typeForMode(DTTOIF(Entry->d_type));
#else
// Other platforms such as Solaris require a stat() to get the type.