From 7c30aebe2d0771244e6b3a416ed8d461761821a9 Mon Sep 17 00:00:00 2001
From: Christian Blichmann <cblichmann@google.com>
Date: Thu, 5 Nov 2020 01:48:46 -0800
Subject: [PATCH] Use Abseil hash maps instead of `std::map<T>`

PiperOrigin-RevId: 340807499
Change-Id: I2689bd1d32be45e3085dcc7a0ba4b8fedd7d53b0
---
 sandboxed_api/sandbox2/BUILD.bazel    |  1 +
 sandboxed_api/sandbox2/CMakeLists.txt |  1 +
 sandboxed_api/sandbox2/client.cc      | 14 +++++---------
 sandboxed_api/sandbox2/client.h       |  4 ++--
 4 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/sandboxed_api/sandbox2/BUILD.bazel b/sandboxed_api/sandbox2/BUILD.bazel
index 839a7e0..11bb0bc 100644
--- a/sandboxed_api/sandbox2/BUILD.bazel
+++ b/sandboxed_api/sandbox2/BUILD.bazel
@@ -343,6 +343,7 @@ cc_library(
         "//sandboxed_api/sandbox2/util:strerror",
         "//sandboxed_api/util:raw_logging",
         "@com_google_absl//absl/base:core_headers",
+        "@com_google_absl//absl/container:flat_hash_map",
         "@com_google_absl//absl/memory",
         "@com_google_absl//absl/strings",
     ],
diff --git a/sandboxed_api/sandbox2/CMakeLists.txt b/sandboxed_api/sandbox2/CMakeLists.txt
index e6a746b..5b64f9e 100644
--- a/sandboxed_api/sandbox2/CMakeLists.txt
+++ b/sandboxed_api/sandbox2/CMakeLists.txt
@@ -328,6 +328,7 @@ add_library(sandbox2_client STATIC
 add_library(sandbox2::client ALIAS sandbox2_client)
 target_link_libraries(sandbox2_client
   PRIVATE absl::core_headers
+          absl::flat_hash_map
           absl::memory
           absl::strings
           sandbox2::logsink
diff --git a/sandboxed_api/sandbox2/client.cc b/sandboxed_api/sandbox2/client.cc
index 5a93020..01f2204 100644
--- a/sandboxed_api/sandbox2/client.cc
+++ b/sandboxed_api/sandbox2/client.cc
@@ -46,22 +46,18 @@
 
 namespace sandbox2 {
 
-constexpr uint32_t Client::kClient2SandboxReady;
-constexpr uint32_t Client::kSandbox2ClientDone;
-constexpr const char* Client::kFDMapEnvVar;
-
 Client::Client(Comms* comms) : comms_(comms) {
   char* fdmap_envvar = getenv(kFDMapEnvVar);
   if (!fdmap_envvar) {
     return;
   }
-  std::map<absl::string_view, absl::string_view> vars =
+  absl::flat_hash_map<absl::string_view, absl::string_view> vars =
       absl::StrSplit(fdmap_envvar, ',', absl::SkipEmpty());
-  for (const auto& var : vars) {
+  for (const auto& [name, mapped_fd] : vars) {
     int fd;
-    SAPI_RAW_CHECK(absl::SimpleAtoi(var.second, &fd), "failed to parse fd map");
-    SAPI_RAW_CHECK(fd_map_.emplace(std::string{var.first}, fd).second,
-                   "could not insert mapping into fd map  (duplicate)");
+    SAPI_RAW_CHECK(absl::SimpleAtoi(mapped_fd, &fd), "failed to parse fd map");
+    SAPI_RAW_CHECK(fd_map_.emplace(std::string(name), fd).second,
+                   "could not insert mapping into fd map (duplicate)");
   }
   unsetenv(kFDMapEnvVar);
 }
diff --git a/sandboxed_api/sandbox2/client.h b/sandboxed_api/sandbox2/client.h
index 9cf63d1..8b1d0aa 100644
--- a/sandboxed_api/sandbox2/client.h
+++ b/sandboxed_api/sandbox2/client.h
@@ -19,10 +19,10 @@
 #define SANDBOXED_API_SANDBOX2_CLIENT_H_
 
 #include <cstdint>
-#include <map>
 #include <memory>
 #include <string>
 
+#include "absl/container/flat_hash_map.h"
 #include "sandboxed_api/sandbox2/comms.h"
 #include "sandboxed_api/sandbox2/logsink.h"
 #include "sandboxed_api/sandbox2/network_proxy/client.h"
@@ -87,7 +87,7 @@ class Client {
   // In the pre-execve case, the sandboxee has to pass the information about
   // file descriptors to the new process. We set an environment variable for
   // this case that is parsed in the Client constructor if present.
-  std::map<std::string, int> fd_map_;
+  absl::flat_hash_map<std::string, int> fd_map_;
 
   std::string GetFdMapEnvVar() const;