From 7f615fc7812e52b04733a77a686ccab99afe4923 Mon Sep 17 00:00:00 2001
From: twinaphex <libretro@gmail.com>
Date: Wed, 12 Aug 2015 15:45:15 +0200
Subject: [PATCH] (memmap) Create wrapper functions memprotect and memsync

---
 libretro-common/include/memmap.h | 14 +++++++++-
 libretro-common/memmap/memmap.c  | 47 +++++++++++++++++++++++++++-----
 2 files changed, 53 insertions(+), 8 deletions(-)

diff --git a/libretro-common/include/memmap.h b/libretro-common/include/memmap.h
index 90b9eef84d..511caee783 100644
--- a/libretro-common/include/memmap.h
+++ b/libretro-common/include/memmap.h
@@ -30,7 +30,7 @@
 #include <errno.h>
 #include <io.h>
 #else
-#define HAVE_MMAP
+#define HAVE_MMAN
 #include <sys/mman.h>
 #endif
 
@@ -38,4 +38,16 @@
 #define MAP_ANONYMOUS MAP_ANON
 #endif
 
+#if !defined(HAVE_MMAN)
+void* mmap(void *desired_addr, size_t len, int mmap_prot, int mmap_flags, int fildes, size_t off);
+
+void munmap(void *base_addr, size_t len);
+
+int mprotect(void *addr, size_t len, int prot);
+#endif
+
+int memsync(void *start, void *end);
+
+int memprotect(void *addr, size_t len);
+
 #endif
diff --git a/libretro-common/memmap/memmap.c b/libretro-common/memmap/memmap.c
index b13e287136..c9540a064b 100644
--- a/libretro-common/memmap/memmap.c
+++ b/libretro-common/memmap/memmap.c
@@ -113,13 +113,24 @@ static void munmap(void *addr, size_t length)
 	UnmapViewOfFile(addr);
 	/* ruh-ro, we leaked handle from CreateFileMapping() ... */
 }
-#elif !defined(HAVE_MMAP)
-#define PROT_EXEC   0x04
-#define MAP_FAILED 0
-#define PROT_READ 0
-#define PROT_WRITE 0
-#define MAP_PRIVATE 0
-#define MAP_ANONYMOUS 0
+
+static int mprotect(void *addr, size_t len, int prot)
+{
+   /* Incomplete, just assumes PAGE_EXECUTE_READWRITE right now
+    * instead of correctly handling prot */
+   prot = 0;
+   if (prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
+      prot = PAGE_EXECUTE_READWRITE;
+   return VirtualProtect(addr, len, prot, 0);
+}
+
+#elif !defined(HAVE_MMAN)
+#define PROT_EXEC       0x04
+#define MAP_FAILED      0
+#define PROT_READ       0
+#define PROT_WRITE      0
+#define MAP_PRIVATE     0
+#define MAP_ANONYMOUS   0
 
 void* mmap(void *desired_addr, size_t len, int mmap_prot, int mmap_flags, int fildes, size_t off)
 {
@@ -139,3 +150,25 @@ int mprotect(void *addr, size_t len, int prot)
 
 #endif
 
+int memsync(void *start, void *end)
+{
+   size_t len = (char*)end - (char*)start;
+   (void)len;
+#if defined(__MACH__) && defined(__arm__)
+   sys_dcache_flush(start ,len);
+   sys_icache_invalidate(start, len);
+   return 0;
+#elif defined(__arm__) && !defined(__QNX__)
+   __clear_cache(start, end);
+   return 0;
+#elif defined(HAVE_MMAN)
+   return msync(start, len, MS_SYNC | MS_CACHE_ONLY | MS_INVALIDATE_ICACHE);
+#else
+   return 0;
+#endif
+}
+
+int memprotect(void *addr, size_t len)
+{
+   return mprotect(addr, len, PROT_READ | PROT_WRITE | PROT_EXEC);
+}