Non-SFI NaCl: Batch-open resource files

ppapi/nacl_irt/manifest_service.cc

 // Copyright 2014 The Chromium 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 "ppapi/nacl_irt/manifest_service.h"
 
 #include "base/message_loop/message_loop_proxy.h"
 #include "ipc/ipc_channel_handle.h"
 #include "ipc/ipc_channel_proxy.h"
 #include "ipc/ipc_sync_message_filter.h"
 #include "native_client/src/trusted/service_runtime/include/sys/errno.h"
 #include "ppapi/nacl_irt/irt_manifest.h"
 #include "ppapi/nacl_irt/plugin_startup.h"
 #include "ppapi/proxy/ppapi_messages.h"
 
+#if !defined(OS_NACL_SFI)
+#include <pthread.h>
+#include <map>
+#include <string>
+#endif
+
 namespace ppapi {
 
 const char kFilePrefix[] = "files/";
 
 // IPC channel is asynchronously set up. So, the NaCl process may try to
 // send a OpenResource message to the host before the connection is
 // established. In such a case, it is necessary to wait for the set up
 // completion.
 class ManifestMessageFilter : public IPC::SyncMessageFilter {
  public:
@@ skipping 87 matching lines @@
   // Copy the file if we received a valid file descriptor. Otherwise, if we got
   // a reply, the file doesn't exist, so provide an fd of -1.
   // See IrtOpenResource() for how this function's result is interpreted.
   if (ipc_fd.is_file())
     *fd = ipc_fd.descriptor().fd;
   else
     *fd = -1;
   return true;
 }
 
+#if !defined(OS_NACL_SFI)
+namespace {
+
+pthread_mutex_t g_mu = PTHREAD_MUTEX_INITIALIZER;
+std::map<std::string, int>* g_prefetched_fds;
+
+}  // namespace
+
+void RegisterPreopenedDescriptorsNonSfi(
+    std::map<std::string, int>* key_fd_map) {
+  pthread_mutex_lock(&g_mu);
+  DCHECK(!g_prefetched_fds);
+  g_prefetched_fds = key_fd_map;
+  pthread_mutex_unlock(&g_mu);
+}
+#endif
+
 int IrtOpenResource(const char* file, int* fd) {
   // Remove leading '/' character.
   if (file[0] == '/')
     ++file;
 
+#if !defined(OS_NACL_SFI)
+  // Fast path for prefetched FDs.
+  pthread_mutex_lock(&g_mu);
+  if (g_prefetched_fds) {
+    std::map<std::string, int>::iterator it = g_prefetched_fds->find(file);
+    if (it != g_prefetched_fds->end()) {
+      *fd = it->second;
+      g_prefetched_fds->erase(it);
+      pthread_mutex_unlock(&g_mu);
+      return 0;
+    }
+  }
+  pthread_mutex_unlock(&g_mu);
+#endif
+
   ManifestService* manifest_service = GetManifestService();
   if (manifest_service == NULL ||
       !manifest_service->OpenResource(file, fd)) {
     return NACL_ABI_EIO;
   }
   return (*fd == -1) ? NACL_ABI_ENOENT : 0;
 }
 
 }  // namespace ppapi