1 files changed, 108 insertions, 0 deletions
diff --git a/src/platform/windows.c b/src/platform/windows.c
new file mode 100644
index 0000000..fb37837
--- /dev/null
+++ b/src/platform/windows.c
@@ -0,0 +1,108 @@
+/* mmap() replacement for Windows
+ *
+ * Author: Mike Frysinger <vapier@gentoo.org>
+ * Modified to not leak the CreateFileMapping-Handle, as well as fixed MAP_PRIVATE to actually work by Markus Mittendrein
+ * Placed into the public domain
+ */
+
+/* References:
+ * CreateFileMapping: http://msdn.microsoft.com/en-us/library/aa366537(VS.85).aspx
+ * CloseHandle:       http://msdn.microsoft.com/en-us/library/ms724211(VS.85).aspx
+ * MapViewOfFile:     http://msdn.microsoft.com/en-us/library/aa366761(VS.85).aspx
+ *                    https://source.winehq.org/source/dlls/kernel32/virtual.c#0356
+ * UnmapViewOfFile:   http://msdn.microsoft.com/en-us/library/aa366882(VS.85).aspx
+ */
+
+#include <io.h>
+#include <windows.h>
+#include <sys/types.h>
+
+#include <stdio.h>
+
+#include "platform.h"
+
+#ifdef __USE_FILE_OFFSET64
+# define DWORD_HI(x) (x >> 32)
+# define DWORD_LO(x) ((x) & 0xffffffff)
+#else
+# define DWORD_HI(x) (0)
+# define DWORD_LO(x) (x)
+#endif
+
+void *cc4group_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset, void** extra)
+{
+	(void)start;
+	if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
+		return MAP_FAILED;
+	if (fd == -1) {
+		if (!(flags & MAP_ANON) || offset)
+			return MAP_FAILED;
+	} else if (flags & MAP_ANON)
+		return MAP_FAILED;
+
+	DWORD flProtect;
+	if (prot & PROT_WRITE) {
+		if (prot & PROT_EXEC) {
+			if(prot & MAP_PRIVATE)
+				flProtect = PAGE_EXECUTE_WRITECOPY;
+			else
+				flProtect = PAGE_EXECUTE_READWRITE;
+		}
+		else {
+			if(prot & MAP_PRIVATE)
+				flProtect = PAGE_WRITECOPY;
+			else
+				flProtect = PAGE_READWRITE;
+		}
+	} else if (prot & PROT_EXEC) {
+		if (prot & PROT_READ)
+			flProtect = PAGE_EXECUTE_READ;
+		else if (prot & PROT_EXEC)
+			flProtect = PAGE_EXECUTE;
+	} else
+		flProtect = PAGE_READONLY;
+
+	off_t end = length + offset;
+	HANDLE mmap_fd, h;
+	if (fd == -1)
+		mmap_fd = INVALID_HANDLE_VALUE;
+	else
+		mmap_fd = (HANDLE)_get_osfhandle(fd);
+	h = CreateFileMapping(mmap_fd, NULL, flProtect, DWORD_HI(end), DWORD_LO(end), NULL);
+	if (h == NULL)
+		return MAP_FAILED;
+
+	DWORD dwDesiredAccess;
+	if (flags & MAP_PRIVATE)
+		dwDesiredAccess = FILE_MAP_COPY;
+	else if (prot & PROT_WRITE)
+		dwDesiredAccess = FILE_MAP_WRITE;
+	else
+		dwDesiredAccess = FILE_MAP_READ;
+	if (prot & PROT_EXEC)
+		dwDesiredAccess |= FILE_MAP_EXECUTE;
+	if (flags & MAP_PRIVATE)
+		dwDesiredAccess |= FILE_MAP_COPY;
+
+	void *ret = MapViewOfFile(h, dwDesiredAccess, DWORD_HI(offset), DWORD_LO(offset), length);
+	if (ret == NULL) {
+		CloseHandle(h);
+		ret = MAP_FAILED;
+	}
+
+	*extra = h;
+
+	return ret;
+}
+
+int cc4group_munmap(void *addr, size_t length, void* extra)
+{
+	(void)length;
+	UnmapViewOfFile(addr);
+	CloseHandle(extra);
+	/* ruh-ro, we leaked handle from CreateFileMapping() ... */
+	return 0;
+}
+
+#undef DWORD_HI
+#undef DWORD_LO