add embedding api lost in mono master merge (#769)

* add embedding api lost in mono master

* Add MMAP overrides

Author: mderoy

mono/utils/mono-filemap.c

@@ -24,9 +24,30 @@
 
 #include "mono-mmap.h"
 
+static MonoFileMapOpen     file_open_func     = 0;
+static MonoFileMapSize     file_size_func     = 0;
+static MonoFileMapFd       file_fd_func       = 0;
+static MonoFileMapClose    file_close_func    = 0;
+       MonoFileMapMap      file_map_func      = 0;
+       MonoFileMapUnmap    file_unmap_func    = 0;
+
+#if defined(ANDROID)
+void mono_file_map_override(MonoFileMapOpen open_func, MonoFileMapSize size_func, MonoFileMapFd fd_func, MonoFileMapClose close_func, MonoFileMapMap map_func, MonoFileMapUnmap unmap_func)
+{
+	file_open_func     = open_func;
+	file_size_func     = size_func;
+	file_fd_func       = fd_func;
+	file_close_func    = close_func;
+	file_map_func      = map_func;
+	file_unmap_func    = unmap_func;
+}
+#endif
+
+
 MonoFileMap *
 mono_file_map_open (const char* name)
 {
+	if (file_open_func) return file_open_func(name);
 #ifdef WIN32
 	gunichar2 *wname = g_utf8_to_utf16 (name, -1, 0, 0, 0);
 	MonoFileMap *result;
@@ -47,6 +68,7 @@ mono_file_map_open (const char* name)
 guint64 
 mono_file_map_size (MonoFileMap *fmap)
 {
+	if (file_size_func) return file_size_func(fmap);
 	struct stat stat_buf;
 	if (fstat (mono_file_map_fd (fmap), &stat_buf) < 0)
 		return 0;
@@ -56,6 +78,7 @@ mono_file_map_size (MonoFileMap *fmap)
 int
 mono_file_map_fd (MonoFileMap *fmap)
 {
+	if (file_fd_func) return file_fd_func(fmap);
 #ifdef WIN32
 	return fileno ((FILE*)fmap);
 #else
@@ -66,6 +89,7 @@ mono_file_map_fd (MonoFileMap *fmap)
 int 
 mono_file_map_close (MonoFileMap *fmap)
 {
+	if (file_close_func) return file_close_func(fmap);
 #ifdef WIN32
 	return fclose ((FILE*)fmap);
 #else

mono/utils/mono-mmap.c

@@ -281,10 +281,20 @@ mono_vfree (void *addr, size_t length, MonoMemAccountType type)
  * \p ret_handle must point to a void*: this value must be used when unmapping
  * the memory area using \c mono_file_unmap().
  */
+extern MonoFileMapMap      file_map_func;
+extern MonoFileMapUnmap    file_unmap_func;
+
 void*
 mono_file_map (size_t length, int flags, int fd, guint64 offset, void **ret_handle)
 {
 	void *ptr;
+	if (file_map_func)
+	{
+		BEGIN_CRITICAL_SECTION;
+		ptr = file_map_func(length, flags, fd, offset, ret_handle);
+		END_CRITICAL_SECTION;
+		return ptr;
+	}
 	int mflags = 0;
 	int prot = prot_from_flags (flags);
 	/* translate the flags */
@@ -320,7 +330,10 @@ mono_file_unmap (void *addr, void *handle)
 	int res;
 
 	BEGIN_CRITICAL_SECTION;
-	res = munmap (addr, (size_t)handle);
+	if (file_unmap_func)
+		res = file_unmap_func(addr, handle);
+	else
+		res = munmap(addr, (size_t)handle);
 	END_CRITICAL_SECTION;
 
 	return res;

mono/utils/mono-mmap.h

@@ -84,5 +84,16 @@ typedef void  (*mono_file_map_release_fn) (void *addr);
 
 MONO_API void mono_file_map_set_allocator (mono_file_map_alloc_fn alloc, mono_file_map_release_fn release);
 
+typedef MonoFileMap* (*MonoFileMapOpen)     (const char* name);
+typedef guint64      (*MonoFileMapSize)     (MonoFileMap *fmap);
+typedef int          (*MonoFileMapFd)       (MonoFileMap *fmap);
+typedef int          (*MonoFileMapClose)    (MonoFileMap *fmap);
+typedef void *       (*MonoFileMapMap)      (size_t length, int flags, int fd, guint64 offset, void **ret_handle);
+typedef int          (*MonoFileMapUnmap)    (void *addr, void *handle);
+
+#if defined(ANDROID)
+MONO_API void mono_file_map_override(MonoFileMapOpen open_func, MonoFileMapSize size_func, MonoFileMapFd fd_func, MonoFileMapClose close_func, MonoFileMapMap map_func, MonoFileMapUnmap unmap_func);
+#endif
+
 #endif /* __MONO_UTILS_MMAP_H__ */