Avoid std::string copying in GetFileNameInWhitelist.

sandbox/linux/services/broker_process.cc

Index: sandbox/linux/services/broker_process.cc
diff --git a/sandbox/linux/services/broker_process.cc b/sandbox/linux/services/broker_process.cc
index d2302ea098215c8188eb74b0d36da37506ff302a..17099c4a2a58538eed6fe1fffd4ca49c50067d3d 100644
--- a/sandbox/linux/services/broker_process.cc
+++ b/sandbox/linux/services/broker_process.cc
@@ -21,6 +21,7 @@
 #include "base/posix/eintr_wrapper.h"
 #include "base/posix/unix_domain_socket_linux.h"
 #include "build/build_config.h"
+#include "sandbox/linux/services/broker_process_utils.h"
 #include "sandbox/linux/services/linux_syscalls.h"
 
 #if defined(OS_ANDROID) && !defined(MSG_CMSG_CLOEXEC)
@@ -53,7 +54,7 @@ static const int kCurrentProcessOpenFlagsMask = O_CLOEXEC;
 // async signal safe if |file_to_open| is NULL.
 // TODO(jln): assert signal safety.
 bool GetFileNameInWhitelist(const std::vector<std::string>& allowed_file_names,
-                            const std::string& requested_filename,
+                            const char* requested_filename,
                             const char** file_to_open) {
   if (file_to_open && *file_to_open) {
     // Make sure that callers never pass a non-empty string. In case callers
@@ -62,12 +63,12 @@ bool GetFileNameInWhitelist(const std::vector<std::string>& allowed_file_names,
     RAW_LOG(FATAL, "*file_to_open should be NULL");
     return false;
   }
-  std::vector<std::string>::const_iterator it;
-  it = std::find(allowed_file_names.begin(), allowed_file_names.end(),
-                 requested_filename);
-  if (it < allowed_file_names.end()) {  // requested_filename was found?
+  const char* found_filename =
+      sandbox::BrokerProcessUtils::Find(requested_filename, allowed_file_names);
+
+  if (found_filename) {  // |requested_filename| was found?
     if (file_to_open)
-      *file_to_open = it->c_str();
+      *file_to_open = found_filename;
     return true;
   }
   return false;
@@ -393,6 +394,7 @@ void BrokerProcess::AccessFileForIPC(const std::string& requested_filename,
   const char* file_to_access = NULL;
   const bool safe_to_access_file = GetFileNameIfAllowedToAccess(
       requested_filename.c_str(), mode, &file_to_access);
+
   if (safe_to_access_file) {
     CHECK(file_to_access);
     int access_ret = access(file_to_access, mode);
@@ -447,8 +449,9 @@ void BrokerProcess::OpenFileForIPC(const std::string& requested_filename,
 // return true if calling access() on this file should be allowed, false
 // otherwise.
 // Async signal safe if and only if |file_to_access| is NULL.
-bool BrokerProcess::GetFileNameIfAllowedToAccess(const char* requested_filename,
-    int requested_mode, const char** file_to_access) const {

[jln (very slow on Chromium), 2013/07/08 22:36:51]

Why the re-indent?

[Jorge Lucangeli Obes, 2013/07/09 03:52:12]

Done.

+bool BrokerProcess::GetFileNameIfAllowedToAccess(
+    const char* requested_filename, int requested_mode,
+    const char** file_to_access) const {
   // First, check if |requested_mode| is existence, ability to read or ability
   // to write. We do not support X_OK.
   if (requested_mode != F_OK &&
@@ -489,8 +492,9 @@ bool BrokerProcess::GetFileNameIfAllowedToAccess(const char* requested_filename,
 // string comparison mechanism.
 // Return true if opening should be allowed, false otherwise.
 // Async signal safe if and only if |file_to_open| is NULL.
-bool BrokerProcess::GetFileNameIfAllowedToOpen(const char* requested_filename,
-    int requested_flags, const char** file_to_open) const {
+bool BrokerProcess::GetFileNameIfAllowedToOpen(
+    const char* requested_filename, int requested_flags,
+    const char** file_to_open) const {

[jln (very slow on Chromium), 2013/07/08 22:36:51]

Why the re-indent?

[Jorge Lucangeli Obes, 2013/07/09 03:52:12]

Done.

   if (!IsAllowedOpenFlags(requested_flags)) {
     return false;
   }