From a01985273bde586468daec716251e05a3a8db5bf Mon Sep 17 00:00:00 2001
From: Twinaphex <libretro@gmail.com>
Date: Sun, 12 Jun 2016 18:42:03 +0200
Subject: [PATCH] Implement frontend_darwin_get_mem_free

---
 frontend/drivers/platform_darwin.m | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/frontend/drivers/platform_darwin.m b/frontend/drivers/platform_darwin.m
index 8d96f398f7..65b49ae891 100644
--- a/frontend/drivers/platform_darwin.m
+++ b/frontend/drivers/platform_darwin.m
@@ -681,6 +681,28 @@ static uint64_t frontend_darwin_get_mem_total(void)
 #endif
 }
 
+static uint64_t frontend_darwin_get_mem_free(void)
+{
+#ifdef OSX
+    vm_size_t page_size;
+    vm_statistics64_data_t vm_stats;
+    mach_port_t mach_port        = mach_host_self();
+    mach_msg_type_number_t count = sizeof(vm_stats) / sizeof(natural_t);
+    
+    if (KERN_SUCCESS == host_page_size(mach_port, &page_size) &&
+        KERN_SUCCESS == host_statistics64(mach_port, HOST_VM_INFO,
+                                          (host_info64_t)&vm_stats, &count))
+    {
+        
+        long long used_memory = ((int64_t)vm_stats.active_count +
+                                 (int64_t)vm_stats.inactive_count +
+                                 (int64_t)vm_stats.wire_count) *  (int64_t)page_size;
+        return used_memory;
+    }
+#endif
+    return 0;
+}
+
 frontend_ctx_driver_t frontend_ctx_darwin = {
    frontend_darwin_get_environment_settings,
    NULL,                         /* init */
@@ -698,6 +720,6 @@ frontend_ctx_driver_t frontend_ctx_darwin = {
    frontend_darwin_get_powerstate,
    frontend_darwin_parse_drive_list,
    frontend_darwin_get_mem_total,
-   NULL,                         /* get_mem_free */
+   frontend_darwin_get_mem_free,
    "darwin",
 };