2 files changed, 68 insertions, 0 deletions
diff --git a/lib/facter/memory.rb b/lib/facter/memory.rb
index aa67702..9dd2e29 100644
--- a/lib/facter/memory.rb
+++ b/lib/facter/memory.rb
@@ -110,6 +110,43 @@ if Facter.value(:kernel) == "OpenBSD"
     end
 end
 
+if Facter.value(:kernel) == "Darwin"
+    swap = Facter::Util::Resolution.exec('sysctl vm.swapusage')
+    swapfree, swaptotal = 0, 0
+    unless swap.empty?
+        # Parse the line:
+        # vm.swapusage: total = 128.00M  used = 0.37M  free = 127.63M  (encrypted)
+        if swap =~ /total\s=\s(\S+)\s+used\s=\s(\S+)\s+free\s=\s(\S+)\s/
+            swaptotal += $1.to_i
+            swapfree  += $3.to_i
+        end
+    end
+
+    Facter.add("SwapSize") do
+        confine :kernel => :Darwin
+        setcode do
+            Facter::Memory.scale_number(swaptotal.to_f,"MB")
+        end
+    end
+
+    Facter.add("SwapFree") do
+        confine :kernel => :Darwin
+        setcode do
+            Facter::Memory.scale_number(swapfree.to_f,"MB")
+        end
+    end
+
+    Facter::Memory.vmstat_darwin_find_free_memory()
+
+    Facter.add("MemoryTotal") do
+        confine :kernel => :Darwin
+        memtotal = Facter::Util::Resolution.exec("sysctl hw.memsize | cut -d':' -f2")
+        setcode do
+            Facter::Memory.scale_number(memtotal.to_f,"")
+        end
+    end
+end
+
 if Facter.value(:kernel) == "SunOS"
     swap = Facter::Util::Resolution.exec('/usr/sbin/swap -l')
     swapfree, swaptotal = 0, 0
diff --git a/lib/facter/util/memory.rb b/lib/facter/util/memory.rb
index 43abec6..029b117 100644
--- a/lib/facter/util/memory.rb
+++ b/lib/facter/util/memory.rb
@@ -62,5 +62,36 @@ module Facter::Memory
             end
         end
     end
+
+    # Darwin had to be different. It's generally opaque with how much RAM it is
+    # using, and this figure could be improved upon too I fear.
+    # Parses the output of "vm_stat", takes the pages free & pages speculative
+    # and multiples that by the page size (also given in output). Ties in with
+    # what activity monitor outputs for free memory.
+    def self.vmstat_darwin_find_free_memory()
+
+        memfree = 0
+        pagesize = 0
+        memspecfree = 0
+
+        vmstats = Facter::Util::Resolution.exec('vm_stat')
+        vmstats.each do |vmline|
+          case
+            when vmline =~ /page\ssize\sof\s(\d+)\sbytes/
+              pagesize = $1.to_i
+            when vmline =~ /^Pages\sfree:\s+(\d+)\./
+              memfree = $1.to_i
+            when vmline =~ /^Pages\sspeculative:\s+(\d+)\./
+              memspecfree = $1.to_i
+          end
+        end
+
+        freemem = ( memfree + memspecfree ) * pagesize
+        Facter.add("MemoryFree") do
+          setcode do
+            Facter::Memory.scale_number(freemem.to_f, "")
+          end
+        end
+    end
 end