Fix most Unicode encoding bugs

Bazel aims to support arbitrary file system path encodings (even raw byte sequences) by attempting to force the JVM to use a Latin-1 locale for OS interactions. As a result, Bazel internally encodes `String`s as raw byte arrays with a Latin-1 coder and no encoding information. Whenever it interacts with encoding-aware APIs, this may require a reencoding of the `String` contents, depending on the OS and availability of a Latin-1 locale.

This PR introduces the concepts of *internal*, *Unicode*, and *platform* strings and adds dedicated optimized functions for converting between these three types (see the class comment on the new `StringEncoding` helper class for details). These functions are then used to standardize and fix conversion throughout the code base. As a result, a number of new end-to-end integration tests for the handling of Unicode in file paths, command-line arguments and environment variables now pass.

Full support for Unicode beyond the current active code page on Windows is left to a follow-up PR as it may require patching the embedded JDK.

* Replace ad-hoc conversion logic with the new consistent set of helper functions.
* Make more parts of the Bazel client's Windows implementation Unicode-aware. This also fixes the behavior of `SetEnv` on Windows, which previously would remove an environment variable if passed an empty value for it, which doesn't match the Unix behavior.
* Drop the `charset` parameter from all methods related to parameter files. The `ISO-8859-1` vs. `UTF-8` choice was flawed since Bazel's internal string representation doesn't maintain any encoding information - `ISO-8859-1` just meant "write out raw bytes", which is the only choice that matches what arguments would look like if passed on the command line.
* Convert server args to the internal string representation. The arguments for requests to the server were already converted to Bazel's internal string representation, which resulted in a mismatch between `--client_cwd` and `--workspace_directory` if the workspace path contains non-ASCII characters.
* Read the downloader config using Bazel's filesystem implementation.
* Make `MacOSXFsEventsDiffAwareness` UTF-8 aware. It previously used the `GetStringUTF` JNI method, which, despite its name, doesn't return the UTF-8 representation of a string, but modified CESU-8 (nobody ever wants this).
* Correctly reencode path strings for `LocalDiffAwareness`.
* Correctly reencode the value of `user.dir`.
* Correctly turn `ExecRequest` fields into strings for `ProcessBuilder` for `bazel --batch run`. This makes it possible to reenable the `test_consistent_command_line_encoding` test, fixing #1775.
* Fix encoding issues in `TargetCompleteEvents`.
* Fix encoding issues in `SubprocessFactory` implementations.
* Drop obsolete warning if `file.encoding` doesn't equal `ISO-8859-1` as file names are encoded with `sun.jnu.encoding` now.
* Consistently reencode internal strings passed into and out of `FileSystem` implementations, e.g. if reading a symlink target. Tests are added that verify the interaction between `FileSystem` implementations and the Java (N)IO APIs on Unicode file paths.

Fixes #1775.

Fixes #11602.

Fixes #18293.

Work towards #374.

Work towards #23859.

Closes #24010.

PiperOrigin-RevId: 694114597
Change-Id: I5bdcbc14a90dd1f0f34698aebcbd07cd2bde7a23

src/main/cpp/BUILD

@@ -143,7 +143,12 @@ cc_binary(
 
 cc_library(
     name = "option_processor",
-    srcs = ["option_processor.cc"],
+    srcs = [
+        "option_processor.cc",
+    ] + select({
+        "//src/conditions:windows": ["option_processor_windows.cc"],
+        "//conditions:default": ["option_processor_unix.cc"],
+    }),
     hdrs = [
         "option_processor.h",
         "option_processor-internal.h",
@@ -179,6 +184,7 @@ cc_library(
         "//src/main/cpp/util",
         "//src/main/cpp/util:blaze_exit_code",
         "//src/main/cpp/util:logging",
+        "@abseil-cpp//absl/strings",
     ],
 )
 

src/main/cpp/blaze.cc

@@ -372,7 +372,9 @@ static vector<string> GetServerExeArgs(const blaze_util::Path &jvm_path,
   }
   result.push_back(java_library_path.str());
 
-  // Force use of latin1 for file names.
+  // TODO: Investigate whether this still has any effect. File name encoding is
+  // governed by sun.jnu.encoding in JDKs with JEP 400, which can't be
+  // influenced by setting a property.
   result.push_back("-Dfile.encoding=ISO-8859-1");
   // Force into the root locale to ensure consistent behavior of string
   // operations across machines (e.g. in the tr_TR locale, capital ASCII 'I'

src/main/cpp/blaze_util_windows.cc

@@ -12,9 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#ifndef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN
-#endif
 #include <windows.h>
 
 #include <fcntl.h>
@@ -937,14 +935,15 @@ void CreateSecureOutputRoot(const blaze_util::Path& path) {
 }
 
 string GetEnv(const string& name) {
-  DWORD size = ::GetEnvironmentVariableA(name.c_str(), nullptr, 0);
+  std::wstring wname = blaze_util::CstringToWstring(name);
+  DWORD size = ::GetEnvironmentVariableW(wname.c_str(), nullptr, 0);
   if (size == 0) {
     return string();  // unset or empty envvar
   }
 
-  unique_ptr<char[]> value(new char[size]);
-  ::GetEnvironmentVariableA(name.c_str(), value.get(), size);
-  return string(value.get());
+  unique_ptr<WCHAR[]> value(new WCHAR[size]);
+  ::GetEnvironmentVariableW(wname.c_str(), value.get(), size);
+  return blaze_util::WstringToCstring(value.get());
 }
 
 string GetPathEnv(const string& name) {
@@ -970,11 +969,14 @@ bool ExistsEnv(const string& name) {
 }
 
 void SetEnv(const string& name, const string& value) {
-  // _putenv_s both calls ::SetEnvionmentVariableA and updates environ(5).
-  _putenv_s(name.c_str(), value.c_str());
+  ::SetEnvironmentVariableW(blaze_util::CstringToWstring(name).c_str(),
+                            blaze_util::CstringToWstring(value).c_str());
 }
 
-void UnsetEnv(const string& name) { SetEnv(name, ""); }
+void UnsetEnv(const string& name) {
+  ::SetEnvironmentVariableW(blaze_util::CstringToWstring(name).c_str(),
+                            nullptr);
+}
 
 bool WarnIfStartedFromDesktop() {
   // GetConsoleProcessList returns:

src/main/cpp/main.cc

@@ -19,9 +19,10 @@
 #include "src/main/cpp/blaze_util_platform.h"
 #include "src/main/cpp/option_processor.h"
 #include "src/main/cpp/startup_options.h"
+#include "src/main/cpp/util/strings.h"
 #include "src/main/cpp/workspace_layout.h"
 
-int main(int argc, char **argv) {
+int main_impl(int argc, char **argv) {
   uint64_t start_time = blaze::GetMillisecondsMonotonic();
   std::unique_ptr<blaze::WorkspaceLayout> workspace_layout(
       new blaze::WorkspaceLayout());
@@ -32,3 +33,23 @@ int main(int argc, char **argv) {
                                                 std::move(startup_options)),
                      start_time);
 }
+
+#ifdef _WIN32
+// Define wmain to support Unicode command line arguments on Windows
+// regardless of the current code page.
+int wmain(int argc, wchar_t **argv) {
+  std::vector<std::string> args;
+  for (int i = 0; i < argc; ++i) {
+    args.push_back(blaze_util::WstringToCstring(argv[i]));
+  }
+  std::vector<char *> c_args;
+  for (const std::string &arg : args) {
+    c_args.push_back(const_cast<char *>(arg.c_str()));
+  }
+  c_args.push_back(nullptr);
+  // Account for the null terminator.
+  return main_impl(c_args.size() - 1, c_args.data());
+}
+#else
+int main(int argc, char **argv) { return main_impl(argc, argv); }
+#endif

src/main/cpp/option_processor-internal.h

@@ -58,6 +58,8 @@ std::string FindRcAlongsideBinary(const std::string& cwd,
 
 blaze_exit_code::ExitCode ParseErrorToExitCode(RcFile::ParseError parse_error);
 
+std::vector<std::string> GetProcessedEnv();
+
 }  // namespace internal
 }  // namespace blaze
 

src/main/cpp/option_processor.cc

@@ -39,6 +39,11 @@
 extern char **environ;
 #endif
 
+#ifdef _WIN32
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#endif
+
 namespace blaze {
 
 using std::map;
@@ -48,7 +53,6 @@ using std::vector;
 
 constexpr char WorkspaceLayout::WorkspacePrefix[];
 static constexpr const char* kRcBasename = ".bazelrc";
-static std::vector<std::string> GetProcessedEnv();
 
 OptionProcessor::OptionProcessor(
     const WorkspaceLayout* workspace_layout,
@@ -512,8 +516,8 @@ blaze_exit_code::ExitCode OptionProcessor::ParseOptions(
     return parse_startup_options_exit_code;
   }
 
-  blazerc_and_env_command_args_ =
-      GetBlazercAndEnvCommandArgs(cwd, rc_file_ptrs, GetProcessedEnv());
+  blazerc_and_env_command_args_ = GetBlazercAndEnvCommandArgs(
+      cwd, rc_file_ptrs, blaze::internal::GetProcessedEnv());
   return blaze_exit_code::SUCCESS;
 }
 
@@ -583,70 +587,6 @@ blaze_exit_code::ExitCode OptionProcessor::ParseStartupOptions(
   return startup_options_->ProcessArgs(rcstartup_flags, error);
 }
 
-static bool IsValidEnvName(const char* p) {
-#if defined(_WIN32) || defined(__CYGWIN__)
-  for (; *p && *p != '='; ++p) {
-    if (!((*p >= 'a' && *p <= 'z') || (*p >= 'A' && *p <= 'Z') ||
-          (*p >= '0' && *p <= '9') || *p == '_' || *p == '(' || *p == ')')) {
-      return false;
-    }
-  }
-#endif
-  return true;
-}
-
-#if defined(_WIN32)
-static void PreprocessEnvString(string* env_str) {
-  static constexpr const char* vars_to_uppercase[] = {"PATH", "SYSTEMROOT",
-                                                      "SYSTEMDRIVE",
-                                                      "TEMP", "TEMPDIR", "TMP"};
-
-  int pos = env_str->find_first_of('=');
-  if (pos == string::npos) return;
-
-  string name = env_str->substr(0, pos);
-  // We do not care about locale. All variable names are ASCII.
-  std::transform(name.begin(), name.end(), name.begin(), ::toupper);
-  if (std::find(std::begin(vars_to_uppercase), std::end(vars_to_uppercase),
-                name) != std::end(vars_to_uppercase)) {
-    env_str->assign(name + "=" + env_str->substr(pos + 1));
-  }
-}
-
-#elif defined(__CYGWIN__)  // not defined(_WIN32)
-
-static void PreprocessEnvString(string* env_str) {
-  int pos = env_str->find_first_of('=');
-  if (pos == string::npos) return;
-  string name = env_str->substr(0, pos);
-  if (name == "PATH") {
-    env_str->assign("PATH=" + env_str->substr(pos + 1));
-  } else if (name == "TMP") {
-    // A valid Windows path "c:/foo" is also a valid Unix path list of
-    // ["c", "/foo"] so must use ConvertPath here. See GitHub issue #1684.
-    env_str->assign("TMP=" + blaze_util::ConvertPath(env_str->substr(pos + 1)));
-  }
-}
-
-#else  // Non-Windows platforms.
-
-static void PreprocessEnvString(const string* env_str) {
-  // do nothing.
-}
-#endif  // defined(_WIN32)
-
-static std::vector<std::string> GetProcessedEnv() {
-  std::vector<std::string> processed_env;
-  for (char** env = environ; *env != nullptr; env++) {
-    string env_str(*env);
-    if (IsValidEnvName(*env)) {
-      PreprocessEnvString(&env_str);
-      processed_env.push_back(std::move(env_str));
-    }
-  }
-  return processed_env;
-}
-
 // IMPORTANT: The options added here do not come from the user. In order for
 // their source to be correctly tracked, the options must either be passed
 // as --default_override=0, 0 being "client", or must be listed in

src/main/cpp/option_processor_unix.cc

@@ -0,0 +1,35 @@
+// Copyright 2024 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <string>
+#include <vector>
+
+#include "src/main/cpp/option_processor-internal.h"
+
+// On OSX, there apparently is no header that defines this.
+#ifndef environ
+extern char** environ;
+#endif
+
+namespace blaze::internal {
+
+std::vector<std::string> GetProcessedEnv() {
+  std::vector<std::string> processed_env;
+  for (char** env = environ; *env != nullptr; env++) {
+    processed_env.emplace_back(*env);
+  }
+  return processed_env;
+}
+
+}  // namespace blaze::internal

src/main/cpp/option_processor_windows.cc

@@ -0,0 +1,94 @@
+// Copyright 2024 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+#include <algorithm>
+#include <string>
+#include <string_view>
+
+#include "absl/strings/ascii.h"
+#include "src/main/cpp/option_processor-internal.h"
+#include "src/main/cpp/util/strings.h"
+
+namespace blaze::internal {
+
+#if defined(__CYGWIN__)
+
+static void PreprocessEnvString(std::string* env_str) {
+  int pos = env_str->find_first_of('=');
+  if (pos == string::npos) {
+    return;
+  }
+  std::string name = env_str->substr(0, pos);
+  if (name == "PATH") {
+    env_str->assign("PATH=" + env_str->substr(pos + 1));
+  } else if (name == "TMP") {
+    // A valid Windows path "c:/foo" is also a valid Unix path list of
+    // ["c", "/foo"] so must use ConvertPath here. See GitHub issue #1684.
+    env_str->assign("TMP=" + blaze_util::ConvertPath(env_str->substr(pos + 1)));
+  }
+}
+
+#else  // not defined(__CYGWIN__)
+
+static void PreprocessEnvString(std::string* env_str) {
+  static constexpr const char* vars_to_uppercase[] = {
+      "PATH", "SYSTEMROOT", "SYSTEMDRIVE", "TEMP", "TEMPDIR", "TMP"};
+
+  std::size_t pos = env_str->find_first_of('=');
+  if (pos == std::string::npos) {
+    return;
+  }
+
+  std::string name = absl::AsciiStrToUpper(env_str->substr(0, pos));
+  if (std::find(std::begin(vars_to_uppercase), std::end(vars_to_uppercase),
+                name) != std::end(vars_to_uppercase)) {
+    env_str->assign(name + "=" + env_str->substr(pos + 1));
+  }
+}
+
+#endif  // defined(__CYGWIN__)
+
+static bool IsValidEnvName(std::string_view s) {
+  std::string_view name = s.substr(0, s.find('='));
+  return std::all_of(name.begin(), name.end(), [](char c) {
+    return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') ||
+           (c >= '0' && c <= '9') || c == '_' || c == '(' || c == ')';
+  });
+}
+
+// Use GetEnvironmentStringsW to get the environment variables to support
+// Unicode regardless of the current code page.
+std::vector<std::string> GetProcessedEnv() {
+  std::vector<std::string> processed_env;
+  wchar_t* env = GetEnvironmentStringsW();
+  if (env == nullptr) {
+    return processed_env;
+  }
+
+  for (wchar_t* p = env; *p != L'\0'; p += wcslen(p) + 1) {
+    std::string env_str = blaze_util::WstringToCstring(p);
+    if (IsValidEnvName(env_str)) {
+      PreprocessEnvString(&env_str);
+      processed_env.push_back(std::move(env_str));
+    }
+  }
+
+  FreeEnvironmentStringsW(env);
+  return processed_env;
+}
+
+}  // namespace blaze::internal

src/main/java/com/google/devtools/build/lib/BUILD

@@ -325,7 +325,6 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/actions:file_metadata",
         "//src/main/java/com/google/devtools/build/lib/actions:important_output_handler",
         "//src/main/java/com/google/devtools/build/lib/actions:localhost_capacity",
-        "//src/main/java/com/google/devtools/build/lib/actions:middleman_type",
         "//src/main/java/com/google/devtools/build/lib/actions:package_roots",
         "//src/main/java/com/google/devtools/build/lib/actions:resource_manager",
         "//src/main/java/com/google/devtools/build/lib/actions:runfiles_tree",
@@ -478,6 +477,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/util:process",
         "//src/main/java/com/google/devtools/build/lib/util:shallow_object_size_computer",
         "//src/main/java/com/google/devtools/build/lib/util:string",
+        "//src/main/java/com/google/devtools/build/lib/util:string_encoding",
         "//src/main/java/com/google/devtools/build/lib/util/io",
         "//src/main/java/com/google/devtools/build/lib/util/io:io-proto",
         "//src/main/java/com/google/devtools/build/lib/util/io:out-err",

src/main/java/com/google/devtools/build/lib/actions/BUILD

@@ -193,7 +193,6 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/util:filetype",
         "//src/main/java/com/google/devtools/build/lib/util:os",
         "//src/main/java/com/google/devtools/build/lib/util:shell_escaper",
-        "//src/main/java/com/google/devtools/build/lib/util:string",
         "//src/main/java/com/google/devtools/build/lib/util:var_int",
         "//src/main/java/com/google/devtools/build/lib/util/io",
         "//src/main/java/com/google/devtools/build/lib/vfs",