Add IRT interface for PNaCl's sandboxed linker to use to talk to Chromium

src/untrusted/irt/irt_dev.h

 /*
  * Copyright (c) 2013 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef NATIVE_CLIENT_SRC_UNTRUSTED_IRT_IRT_DEV_H_
 #define NATIVE_CLIENT_SRC_UNTRUSTED_IRT_IRT_DEV_H_
 
 #include <stdarg.h>
 #include <stddef.h>
@@ skipping 100 matching lines @@
 struct nacl_irt_dev_list_mappings {
   int (*list_mappings)(struct NaClMemMappingInfo *regions,
                        size_t count, size_t *result_count);
 };
 
 #define NACL_IRT_DEV_GETPID_v0_1 "nacl-irt-dev-getpid-0.1"
 struct nacl_irt_dev_getpid {
   int (*getpid)(int *pid);
 };
 
+/*
+ * This is an internal interface, for use by PNaCl's sandboxed linker for
+ * communicating with the browser.
+ *
+ * serve_link_request(func) waits for a request via IPC, and then calls
+ * func(), on the same thread.
+ *
+ * |nexe_fd| is a writable FD for the linker to write its output to.
+ * |obj_file_fds| is an array of readable FDs (of length
+ * |obj_file_fd_count|) of input object files.  func() returns zero on
+ * success or a non-zero value on error.
+ */
+#define NACL_IRT_PRIVATE_PNACL_TRANSLATOR_LINK_v0_1 \
+    "nacl-irt-private-pnacl-translator-link-0.1"
+struct nacl_irt_private_pnacl_translator_link {
+  void (*serve_link_request)(int (*func)(int nexe_fd,
+                                         const int *obj_file_fds,
+                                         int obj_file_fd_count));
+};
+
 #if defined(__cplusplus)
 }
 #endif
 
 #endif /* NATIVE_CLIENT_SRC_UNTRUSTED_IRT_IRT_DEV_H */