Clarify that dollars in cost estimates are USD.

This commit was sponsored by Ignacio on Patreon.

3 files changed, 7 insertions, 4 deletions

diff --git a/CHANGELOG b/CHANGELOG
index b657f75..5baf899 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -4,6 +4,7 @@ keysafe (0.20161108) UNRELEASED; urgency=medium
     However, the stack.yaml is still using an old LTS version
     to avoid polynomial's failure to build with ghc 8.0
     (https://github.com/mokus0/polynomial/issues/8)
+  * Clarify that dollars in cost estimates are USD.
 
  -- Joey Hess <id@joeyh.name>  Tue, 29 Nov 2016 22:27:01 -0400
 
diff --git a/Cost.hs b/Cost.hs
index dc2438e..a18a088 100644
--- a/Cost.hs
+++ b/Cost.hs
@@ -92,6 +92,7 @@ estimateAttackCost dc opcost = centsToDollars $ costcents
 newtype Cents = Cents Integer
 	deriving (Num, Integral, Enum, Real, Ord, Eq, Show)
 
+-- | USD
 newtype Dollars = Dollars Integer
 	deriving (Num, Integral, Enum, Real, Ord, Eq)
 
@@ -103,12 +104,13 @@ instance Show Dollars where
 		, (1000, "thousand")
 		]
 	  where
-		go [] = "$" ++ show n
+		go [] = fmt (show n)
 		go ((d, u):us)
 			| n >= d = 
 				let n' = n `div` d
-				in "$" ++ show n' ++ " " ++ u
+				in fmt (show n' ++ " " ++ u)
 			| otherwise = go us
+		fmt d = "$" ++ d ++ " (USD)"
 
 centsToDollars :: Cents -> Dollars
 centsToDollars (Cents c) = Dollars (c `div` 100)
diff --git a/keysafe.1 b/keysafe.1
index a09bf6f..6b75c8a 100644
--- a/keysafe.1
+++ b/keysafe.1
@@ -28,8 +28,8 @@ the secret key with the password in a way that takes a lot of computation
 to decrypt. This makes it hard for an attacker to crack your password,
 because each guess they make costs them.
 .PP
-Keysafe is designed so that it should take millions of dollars of computer
-time to crack any fairly good password. With a truly good
+Keysafe is designed so that it should take millions of dollars (US)
+of computer time to crack any fairly good password. With a truly good
 password, such as four random words, the cracking cost should be many
 trillions of dollars. Keysafe checks your password strength (using the
 zxcvbn library), and shows an estimate of the cost to crack your password,