base: Support command line wrappers with quoted arguments

base/command_line.cc

 // Copyright (c) 2012 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 "base/command_line.h"
 
 #include <algorithm>
 #include <ostream>
 
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/strings/string_split.h"
+#include "base/strings/string_tokenizer.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <shellapi.h>
 #endif
 
 namespace base {
@@ skipping 380 matching lines @@
 void CommandLine::AppendArguments(const CommandLine& other,
                                   bool include_program) {
   if (include_program)
     SetProgram(other.GetProgram());
   AppendSwitchesAndArguments(this, other.argv());
 }
 
 void CommandLine::PrependWrapper(const CommandLine::StringType& wrapper) {
   if (wrapper.empty())
     return;
-  // The wrapper may have embedded arguments (like "gdb --args"). In this case,
-  // we don't pretend to do anything fancy, we just split on spaces.
-  StringVector wrapper_argv = SplitString(
-      wrapper, FilePath::StringType(1, ' '), base::TRIM_WHITESPACE,
-      base::SPLIT_WANT_ALL);
-  // Prepend the wrapper and update the switches/arguments |begin_args_|.
-  argv_.insert(argv_.begin(), wrapper_argv.begin(), wrapper_argv.end());
-  begin_args_ += wrapper_argv.size();
+  // Split the wrapper command based on whitespace (with quoting).
+  StringTokenizer tokenizer(wrapper, " ");

[gab, 2017/03/28 17:03:59]

This won't compile on Windows I think (CommandLine::StringType will be string16)

using CommandLineTokenizer = StringTokenizerT<CommandLine::StringType,
CommandLine::StringType::const_iterator>;

will probably work?

[Sami, 2017/03/28 17:54:09]

Ah, thanks for the tip! Done.

+  tokenizer.set_quote_chars("'\"");
+  // Prepend the wrapper and update the switches/arguments |begin_args_|
+  auto it = argv_.begin();
+  while (tokenizer.GetNext()) {
+    it = argv_.emplace(it, tokenizer.token()) + 1;

[gab, 2017/03/28 17:03:59]

Pushing in front of vector repeatedly is inefficient, build outside of loop and
insert in one pass like SplitString() approach effectively used to do?

[Sami, 2017/03/28 17:54:09]

Right you are -- done.

+    begin_args_++;

[gab, 2017/03/28 17:04:00]

Irrelevant after above comment but FWIW: prefer pre-increment when it's
equivalent

[Sami, 2017/03/28 17:54:09]

Acknowledged.

+  }
 }
 
 #if defined(OS_WIN)
 void CommandLine::ParseFromString(const string16& command_line) {
   string16 command_line_string;
   TrimWhitespace(command_line, TRIM_ALL, &command_line_string);
   if (command_line_string.empty())
     return;
 
   int num_args = 0;
@@ skipping 52 matching lines @@
   return params;
 }
 
 void CommandLine::ResetStringPieces() {
   switches_by_stringpiece_.clear();
   for (const auto& entry : switches_)
     switches_by_stringpiece_[entry.first] = &(entry.second);
 }
 
 }  // namespace base