[Solaris] Fix PR33228 - llvm::sys::fs::is_local_impl done right

[fedor.sergeev]

Summary

Solaris-specific implementation for llvm::sys::fs::is_local_impl.
FStype pattern matching might be a bit unreliable, but at least it fixes the build failure.

[krytarowski]

Illumos uses __sun, not __sun__. I know that __something__ is more POSIX friendly, but does it handle only commercial Solaris? What version?

[fedor.sergeev]

In D33695#768261, @krytarowski wrote:

Illumos uses __sun, not __sun__. I know that __something__ is more POSIX friendly, but does it handle only commercial Solaris? What version?

gcc on Solaris 10/11 sparc/intel specifies both __sun and __sun__.
I can see __sun being used in llvm sources once, but none of __sun__.
I will switch to __sun.

[fedor.sergeev]

__sun__ -> __sun

[krytarowski]

Looks correct, in theory f_flag could be investigated, but there are no exported values to userspace.

The same solution is used in LibreOffice: https://github.com/LibreOffice/core/blob/35f3759e5ca44bc7bc8f275833e1be54494c5ff3/sal/osl/unx/file_volume.cxx#L177

I don't see a better way to handle it.

[krytarowski]

lib/Support/Unix/Path.inc

387

This is true at least for Illumos.

[fedor.sergeev]

I'm new to all this process/machinery, what should be my next action?
How integration is done for the change that is "Reviewed"?

thanks,

Fedor.

[krytarowski]

I can commit it within 24h if nobody will complain.

lib/Support/Unix/Path.inc

#endif
   case CIFS_MAGIC_NUMBER:
     return false;
   default:
     return true;
   }
 #elif defined(__CYGWIN__)
   // Cygwin doesn't expose this information; would need to use Win32 API.
   return false;
+#elif defined(__sun)
+  // statvfs::f_basetype contains a null-terminated FSType name of the mounted target
+  StringRef fstype(Vfs.f_basetype);
+  // NFS is the only non-local fstype??
+  return !fstype.equals("nfs");
 #else
   return !!(STATVFS_F_FLAG(Vfs) & MNT_LOCAL);
 #endif
 }
 
 std::error_code is_local(const Twine &Path, bool &Result) {
   struct STATVFS Vfs;
   if (::STATVFS(Path.str().c_str(), &Vfs))