syscallcompat: move quirks logic here & fix darwin

We need to look at f_fstypename acc. to
https://stackoverflow.com/a/52299141/1380267 :

> As filesystem type numbers are now assigned at runtime in
> recent versions of MacOS, you must use f_fstypename to
> determine the type.

https://github.com/rfjakob/gocryptfs/issues/585

1 files changed, 20 insertions, 0 deletions

diff --git a/internal/syscallcompat/quirks.go b/internal/syscallcompat/quirks.go
new file mode 100644
index 0000000..60d584d
--- /dev/null
+++ b/internal/syscallcompat/quirks.go
@@ -0,0 +1,20 @@
+package syscallcompat
+
+import (
+	"github.com/rfjakob/gocryptfs/internal/tlog"
+)
+
+const (
+	// QuirkBrokenFalloc means the falloc is broken.
+	// Preallocation on Btrfs is broken ( https://github.com/rfjakob/gocryptfs/issues/395 )
+	// and slow ( https://github.com/rfjakob/gocryptfs/issues/63 ).
+	QuirkBrokenFalloc = uint64(1 << iota)
+	// QuirkDuplicateIno1 means that we have duplicate inode numbers.
+	// On MacOS ExFAT, all empty files share inode number 1:
+	// https://github.com/rfjakob/gocryptfs/issues/585
+	QuirkDuplicateIno1
+)
+
+func logQuirk(s string) {
+	tlog.Info.Printf(tlog.ColorYellow + "DetectQuirks: " + s + tlog.ColorReset)
+}