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

src/untrusted/irt/irt_pnacl_translator.c

+/*
+ * Copyright (c) 2015 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.
+ */
+
+#include "native_client/src/shared/platform/nacl_log.h"
+#include "native_client/src/shared/srpc/nacl_srpc.h"
+#include "native_client/src/untrusted/irt/irt_dev.h"
+#include "native_client/src/untrusted/irt/irt_interfaces.h"
+
+static const int kMaxObjectFiles = 16;
+
+static int (*g_func)(int nexe_fd,
+                     const int *obj_file_fds,
+                     int obj_file_fd_count);
+
+static void handle_link_request(NaClSrpcRpc *rpc,
+                                NaClSrpcArg **in_args,
+                                NaClSrpcArg **out_args,
+                                NaClSrpcClosure *done) {
+  int obj_file_count = in_args[0]->u.ival;
+  int nexe_fd = in_args[kMaxObjectFiles + 1]->u.hval;
+
+  if (obj_file_count < 1 || obj_file_count > kMaxObjectFiles) {
+    NaClLog(LOG_FATAL, "Bad object file count (%i)\n", obj_file_count);
+  }
+  int obj_file_fds[obj_file_count];
+  int i;
+  for (i = 0; i < obj_file_count; i++) {

[jvoung (off chromium), 2015/02/05 19:14:11]

nit: could scope the "int i;" in the loop?

[Mark Seaborn, 2015/02/05 22:01:32]

Done.  I didn't actually realise that is allowed in C99 as well as C++.

+    obj_file_fds[i] = in_args[i + 1]->u.hval;
+  }
+
+  int result = g_func(nexe_fd, obj_file_fds, obj_file_count);
+
+  rpc->result = result == 0 ? NACL_SRPC_RESULT_OK : NACL_SRPC_RESULT_APP_ERROR;
+  done->Run(done);
+}
+
+static const struct NaClSrpcHandlerDesc srpc_methods[] = {
+  { "RunWithSplit:ihhhhhhhhhhhhhhhhh:", handle_link_request },
+  { NULL, NULL },
+};
+
+static void serve_link_request(int (*func)(int nexe_fd,
+                                           const int *obj_file_fds,
+                                           int obj_file_fd_count)) {
+  g_func = func;
+  if (!NaClSrpcModuleInit()) {
+    NaClLog(LOG_FATAL, "NaClSrpcModuleInit() failed\n");
+  }
+  NaClSrpcAcceptClientConnection(srpc_methods);
+}
+
+const struct nacl_irt_private_pnacl_translator_link
+    nacl_irt_private_pnacl_translator_link = {
+  serve_link_request,
+};