// 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 #include "base/check_op.h" #include "base/containers/contains.h" #include "base/containers/span.h" #include "base/files/file_path.h" #include "base/logging.h" #include "base/notreached.h" #include "base/numerics/checked_math.h" #include "base/ranges/algorithm.h" #include "base/strings/strcat.h" #include "base/strings/string_piece.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 BUILDFLAG(IS_WIN) #include #include #include "base/strings/string_util_win.h" #endif // BUILDFLAG(IS_WIN) namespace base { CommandLine* CommandLine::current_process_commandline_ = nullptr; namespace { DuplicateSwitchHandler* g_duplicate_switch_handler = nullptr; constexpr CommandLine::CharType kSwitchTerminator[] = FILE_PATH_LITERAL("--"); constexpr CommandLine::CharType kSwitchValueSeparator[] = FILE_PATH_LITERAL("="); // Since we use a lazy match, make sure that longer versions (like "--") are // listed before shorter versions (like "-") of similar prefixes. #if BUILDFLAG(IS_WIN) // By putting slash last, we can control whether it is treaded as a switch // value by changing the value of switch_prefix_count to be one less than // the array size. constexpr CommandLine::StringPieceType kSwitchPrefixes[] = {L"--", L"-", L"/"}; #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) // Unixes don't use slash as a switch. constexpr CommandLine::StringPieceType kSwitchPrefixes[] = {"--", "-"}; #endif size_t switch_prefix_count = std::size(kSwitchPrefixes); #if BUILDFLAG(IS_WIN) // Switch string that specifies the single argument to the command line. // If present, everything after this switch is interpreted as a single // argument regardless of whitespace, quotes, etc. Used for launches from the // Windows shell, which may have arguments with unencoded quotes that could // otherwise unexpectedly be split into multiple arguments // (https://crbug.com/937179). constexpr CommandLine::CharType kSingleArgument[] = FILE_PATH_LITERAL("single-argument"); #endif // BUILDFLAG(IS_WIN) size_t GetSwitchPrefixLength(CommandLine::StringPieceType string) { for (size_t i = 0; i < switch_prefix_count; ++i) { CommandLine::StringType prefix(kSwitchPrefixes[i]); if (string.substr(0, prefix.length()) == prefix) return prefix.length(); } return 0; } // Fills in |switch_string| and |switch_value| if |string| is a switch. // This will preserve the input switch prefix in the output |switch_string|. bool IsSwitch(const CommandLine::StringType& string, CommandLine::StringType* switch_string, CommandLine::StringType* switch_value) { switch_string->clear(); switch_value->clear(); size_t prefix_length = GetSwitchPrefixLength(string); if (prefix_length == 0 || prefix_length == string.length()) return false; const size_t equals_position = string.find(kSwitchValueSeparator); *switch_string = string.substr(0, equals_position); if (equals_position != CommandLine::StringType::npos) *switch_value = string.substr(equals_position + 1); return true; } // Returns true iff |string| represents a switch with key // |switch_key_without_prefix|, regardless of value. bool IsSwitchWithKey(CommandLine::StringPieceType string, CommandLine::StringPieceType switch_key_without_prefix) { size_t prefix_length = GetSwitchPrefixLength(string); if (prefix_length == 0 || prefix_length == string.length()) return false; const size_t equals_position = string.find(kSwitchValueSeparator); return string.substr(prefix_length, equals_position - prefix_length) == switch_key_without_prefix; } #if BUILDFLAG(IS_WIN) // Quote a string as necessary for CommandLineToArgvW compatibility *on // Windows*. std::wstring QuoteForCommandLineToArgvW(const std::wstring& arg, bool allow_unsafe_insert_sequences) { // Ensure that GetCommandLineString isn't used to generate command-line // strings for the Windows shell by checking for Windows insert sequences like // "%1". GetCommandLineStringForShell should be used instead to get a string // with the correct placeholder format for the shell. DCHECK(arg.size() != 2 || arg[0] != L'%' || allow_unsafe_insert_sequences); // We follow the quoting rules of CommandLineToArgvW. // http://msdn.microsoft.com/en-us/library/17w5ykft.aspx std::wstring quotable_chars(L" \\\""); if (arg.find_first_of(quotable_chars) == std::wstring::npos) { // No quoting necessary. return arg; } std::wstring out; out.push_back('"'); for (size_t i = 0; i < arg.size(); ++i) { if (arg[i] == '\\') { // Find the extent of this run of backslashes. size_t start = i, end = start + 1; for (; end < arg.size() && arg[end] == '\\'; ++end) {} size_t backslash_count = end - start; // Backslashes are escapes only if the run is followed by a double quote. // Since we also will end the string with a double quote, we escape for // either a double quote or the end of the string. if (end == arg.size() || arg[end] == '"') { // To quote, we need to output 2x as many backslashes. backslash_count *= 2; } for (size_t j = 0; j < backslash_count; ++j) out.push_back('\\'); // Advance i to one before the end to balance i++ in loop. i = end - 1; } else if (arg[i] == '"') { out.push_back('\\'); out.push_back('"'); } else { out.push_back(arg[i]); } } out.push_back('"'); return out; } #endif // BUILDFLAG(IS_WIN) } // namespace // static void CommandLine::SetDuplicateSwitchHandler( std::unique_ptr new_duplicate_switch_handler) { delete g_duplicate_switch_handler; g_duplicate_switch_handler = new_duplicate_switch_handler.release(); } CommandLine::CommandLine(NoProgram no_program) : argv_(1), begin_args_(1) {} CommandLine::CommandLine(const FilePath& program) : argv_(1), begin_args_(1) { SetProgram(program); } CommandLine::CommandLine(int argc, const CommandLine::CharType* const* argv) : argv_(1), begin_args_(1) { InitFromArgv(argc, argv); } CommandLine::CommandLine(const StringVector& argv) : argv_(1), begin_args_(1) { InitFromArgv(argv); } CommandLine::CommandLine(const CommandLine& other) = default; CommandLine& CommandLine::operator=(const CommandLine& other) = default; CommandLine::~CommandLine() = default; #if BUILDFLAG(IS_WIN) // static void CommandLine::set_slash_is_not_a_switch() { // The last switch prefix should be slash, so adjust the size to skip it. static_assert(base::make_span(kSwitchPrefixes).back() == L"/", "Error: Last switch prefix is not a slash."); switch_prefix_count = std::size(kSwitchPrefixes) - 1; } // static void CommandLine::InitUsingArgvForTesting(int argc, const char* const* argv) { DCHECK(!current_process_commandline_); current_process_commandline_ = new CommandLine(NO_PROGRAM); // On Windows we need to convert the command line arguments to std::wstring. CommandLine::StringVector argv_vector; for (int i = 0; i < argc; ++i) argv_vector.push_back(UTF8ToWide(argv[i])); current_process_commandline_->InitFromArgv(argv_vector); } #endif // BUILDFLAG(IS_WIN) // static bool CommandLine::Init(int argc, const char* const* argv) { if (current_process_commandline_) { // If this is intentional, Reset() must be called first. If we are using // the shared build mode, we have to share a single object across multiple // shared libraries. return false; } current_process_commandline_ = new CommandLine(NO_PROGRAM); #if BUILDFLAG(IS_WIN) current_process_commandline_->ParseFromString(::GetCommandLineW()); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) current_process_commandline_->InitFromArgv(argc, argv); #else #error Unsupported platform #endif return true; } // static void CommandLine::Reset() { DCHECK(current_process_commandline_); delete current_process_commandline_; current_process_commandline_ = nullptr; } // static CommandLine* CommandLine::ForCurrentProcess() { DCHECK(current_process_commandline_); return current_process_commandline_; } // static bool CommandLine::InitializedForCurrentProcess() { return !!current_process_commandline_; } #if BUILDFLAG(IS_WIN) // static CommandLine CommandLine::FromString(StringPieceType command_line) { CommandLine cmd(NO_PROGRAM); cmd.ParseFromString(command_line); return cmd; } #endif // BUILDFLAG(IS_WIN) void CommandLine::InitFromArgv(int argc, const CommandLine::CharType* const* argv) { StringVector new_argv; for (int i = 0; i < argc; ++i) new_argv.push_back(argv[i]); InitFromArgv(new_argv); } void CommandLine::InitFromArgv(const StringVector& argv) { argv_ = StringVector(1); switches_.clear(); begin_args_ = 1; SetProgram(argv.empty() ? FilePath() : FilePath(argv[0])); AppendSwitchesAndArguments(argv); } FilePath CommandLine::GetProgram() const { return FilePath(argv_[0]); } void CommandLine::SetProgram(const FilePath& program) { #if BUILDFLAG(IS_WIN) argv_[0] = StringType(TrimWhitespace(program.value(), TRIM_ALL)); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) TrimWhitespaceASCII(program.value(), TRIM_ALL, &argv_[0]); #else #error Unsupported platform #endif } bool CommandLine::HasSwitch(StringPiece switch_string) const { DCHECK_EQ(ToLowerASCII(switch_string), switch_string); return Contains(switches_, switch_string); } bool CommandLine::HasSwitch(const char switch_constant[]) const { return HasSwitch(StringPiece(switch_constant)); } std::string CommandLine::GetSwitchValueASCII(StringPiece switch_string) const { StringType value = GetSwitchValueNative(switch_string); #if BUILDFLAG(IS_WIN) if (!IsStringASCII(base::AsStringPiece16(value))) { #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) if (!IsStringASCII(value)) { #endif DLOG(WARNING) << "Value of switch (" << switch_string << ") must be ASCII."; return std::string(); } #if BUILDFLAG(IS_WIN) return WideToUTF8(value); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) return value; #endif } FilePath CommandLine::GetSwitchValuePath(StringPiece switch_string) const { return FilePath(GetSwitchValueNative(switch_string)); } CommandLine::StringType CommandLine::GetSwitchValueNative( StringPiece switch_string) const { DCHECK_EQ(ToLowerASCII(switch_string), switch_string); auto result = switches_.find(switch_string); return result == switches_.end() ? StringType() : result->second; } void CommandLine::AppendSwitch(StringPiece switch_string) { AppendSwitchNative(switch_string, StringType()); } void CommandLine::AppendSwitchPath(StringPiece switch_string, const FilePath& path) { AppendSwitchNative(switch_string, path.value()); } void CommandLine::AppendSwitchNative(StringPiece switch_string, CommandLine::StringPieceType value) { #if BUILDFLAG(IS_WIN) const std::string switch_key = ToLowerASCII(switch_string); StringType combined_switch_string(UTF8ToWide(switch_key)); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) StringPiece switch_key = switch_string; StringType combined_switch_string(switch_key); #endif size_t prefix_length = GetSwitchPrefixLength(combined_switch_string); auto key = switch_key.substr(prefix_length); if (g_duplicate_switch_handler) { g_duplicate_switch_handler->ResolveDuplicate(key, value, switches_[std::string(key)]); } else { switches_[std::string(key)] = StringType(value); } // Preserve existing switch prefixes in |argv_|; only append one if necessary. if (prefix_length == 0) { combined_switch_string.insert(0, kSwitchPrefixes[0].data(), kSwitchPrefixes[0].size()); } if (!value.empty()) base::StrAppend(&combined_switch_string, {kSwitchValueSeparator, value}); // Append the switch and update the switches/arguments divider |begin_args_|. argv_.insert(argv_.begin() + begin_args_, combined_switch_string); begin_args_ = (CheckedNumeric(begin_args_) + 1).ValueOrDie(); } void CommandLine::AppendSwitchASCII(StringPiece switch_string, StringPiece value_string) { #if BUILDFLAG(IS_WIN) AppendSwitchNative(switch_string, UTF8ToWide(value_string)); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) AppendSwitchNative(switch_string, value_string); #else #error Unsupported platform #endif } void CommandLine::RemoveSwitch(base::StringPiece switch_key_without_prefix) { #if BUILDFLAG(IS_WIN) StringType switch_key_native = UTF8ToWide(switch_key_without_prefix); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) StringType switch_key_native(switch_key_without_prefix); #endif DCHECK_EQ(ToLowerASCII(switch_key_without_prefix), switch_key_without_prefix); DCHECK_EQ(0u, GetSwitchPrefixLength(switch_key_native)); auto it = switches_.find(switch_key_without_prefix); if (it == switches_.end()) return; switches_.erase(it); // Also erase from the switches section of |argv_| and update |begin_args_| // accordingly. // Switches in |argv_| have indices [1, begin_args_). auto argv_switches_begin = argv_.begin() + 1; auto argv_switches_end = argv_.begin() + begin_args_; DCHECK(argv_switches_begin <= argv_switches_end); DCHECK(argv_switches_end <= argv_.end()); auto expell = std::remove_if(argv_switches_begin, argv_switches_end, [&switch_key_native](const StringType& arg) { return IsSwitchWithKey(arg, switch_key_native); }); if (expell == argv_switches_end) { NOTREACHED(); return; } begin_args_ -= argv_switches_end - expell; argv_.erase(expell, argv_switches_end); } void CommandLine::CopySwitchesFrom(const CommandLine& source, const char* const switches[], size_t count) { for (size_t i = 0; i < count; ++i) { if (source.HasSwitch(switches[i])) AppendSwitchNative(switches[i], source.GetSwitchValueNative(switches[i])); } } CommandLine::StringVector CommandLine::GetArgs() const { // Gather all arguments after the last switch (may include kSwitchTerminator). StringVector args(argv_.begin() + begin_args_, argv_.end()); // Erase only the first kSwitchTerminator (maybe "--" is a legitimate page?) auto switch_terminator = ranges::find(args, kSwitchTerminator); if (switch_terminator != args.end()) args.erase(switch_terminator); return args; } void CommandLine::AppendArg(StringPiece value) { #if BUILDFLAG(IS_WIN) DCHECK(IsStringUTF8(value)); AppendArgNative(UTF8ToWide(value)); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) AppendArgNative(value); #else #error Unsupported platform #endif } void CommandLine::AppendArgPath(const FilePath& path) { AppendArgNative(path.value()); } void CommandLine::AppendArgNative(StringPieceType value) { argv_.push_back(StringType(value)); } void CommandLine::AppendArguments(const CommandLine& other, bool include_program) { if (include_program) SetProgram(other.GetProgram()); AppendSwitchesAndArguments(other.argv()); } void CommandLine::PrependWrapper(StringPieceType wrapper) { if (wrapper.empty()) return; // Split the wrapper command based on whitespace (with quoting). // StringPieceType does not currently work directly with StringTokenizerT. using CommandLineTokenizer = StringTokenizerT; StringType wrapper_string(wrapper); CommandLineTokenizer tokenizer(wrapper_string, FILE_PATH_LITERAL(" ")); tokenizer.set_quote_chars(FILE_PATH_LITERAL("'\"")); std::vector wrapper_argv; while (tokenizer.GetNext()) wrapper_argv.emplace_back(tokenizer.token()); // 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(); } #if BUILDFLAG(IS_WIN) void CommandLine::ParseFromString(StringPieceType command_line) { command_line = TrimWhitespace(command_line, TRIM_ALL); if (command_line.empty()) return; raw_command_line_string_ = command_line; int num_args = 0; wchar_t** args = NULL; // When calling CommandLineToArgvW, use the apiset if available. // Doing so will bypass loading shell32.dll on Win8+. HMODULE downlevel_shell32_dll = ::LoadLibraryEx(L"api-ms-win-downlevel-shell32-l1-1-0.dll", nullptr, LOAD_LIBRARY_SEARCH_SYSTEM32); if (downlevel_shell32_dll) { auto command_line_to_argv_w_proc = reinterpret_cast( ::GetProcAddress(downlevel_shell32_dll, "CommandLineToArgvW")); if (command_line_to_argv_w_proc) args = command_line_to_argv_w_proc(command_line.data(), &num_args); } else { // Since the apiset is not available, allow the delayload of shell32.dll // to take place. args = ::CommandLineToArgvW(command_line.data(), &num_args); } DPLOG_IF(FATAL, !args) << "CommandLineToArgvW failed on command line: " << command_line; StringVector argv(args, args + num_args); InitFromArgv(argv); raw_command_line_string_ = StringPieceType(); LocalFree(args); if (downlevel_shell32_dll) ::FreeLibrary(downlevel_shell32_dll); } #endif // BUILDFLAG(IS_WIN) void CommandLine::AppendSwitchesAndArguments( const CommandLine::StringVector& argv) { bool parse_switches = true; #if BUILDFLAG(IS_WIN) const bool is_parsed_from_string = !raw_command_line_string_.empty(); #endif for (size_t i = 1; i < argv.size(); ++i) { CommandLine::StringType arg = argv[i]; #if BUILDFLAG(IS_WIN) arg = CommandLine::StringType(TrimWhitespace(arg, TRIM_ALL)); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) TrimWhitespaceASCII(arg, TRIM_ALL, &arg); #endif CommandLine::StringType switch_string; CommandLine::StringType switch_value; parse_switches &= (arg != kSwitchTerminator); if (parse_switches && IsSwitch(arg, &switch_string, &switch_value)) { #if BUILDFLAG(IS_WIN) if (is_parsed_from_string && IsSwitchWithKey(switch_string, kSingleArgument)) { ParseAsSingleArgument(switch_string); return; } AppendSwitchNative(WideToUTF8(switch_string), switch_value); #elif BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA) AppendSwitchNative(switch_string, switch_value); #else #error Unsupported platform #endif } else { AppendArgNative(arg); } } } CommandLine::StringType CommandLine::GetArgumentsStringInternal( bool allow_unsafe_insert_sequences) const { StringType params; // Append switches and arguments. bool parse_switches = true; for (size_t i = 1; i < argv_.size(); ++i) { StringType arg = argv_[i]; StringType switch_string; StringType switch_value; parse_switches &= arg != kSwitchTerminator; if (i > 1) params.append(FILE_PATH_LITERAL(" ")); if (parse_switches && IsSwitch(arg, &switch_string, &switch_value)) { params.append(switch_string); if (!switch_value.empty()) { #if BUILDFLAG(IS_WIN) switch_value = QuoteForCommandLineToArgvW( switch_value, allow_unsafe_insert_sequences); #endif params.append(kSwitchValueSeparator + switch_value); } } else { #if BUILDFLAG(IS_WIN) arg = QuoteForCommandLineToArgvW(arg, allow_unsafe_insert_sequences); #endif params.append(arg); } } return params; } CommandLine::StringType CommandLine::GetCommandLineString() const { StringType string(argv_[0]); #if BUILDFLAG(IS_WIN) string = QuoteForCommandLineToArgvW(string, /*allow_unsafe_insert_sequences=*/false); #endif StringType params(GetArgumentsString()); if (!params.empty()) { string.append(FILE_PATH_LITERAL(" ")); string.append(params); } return string; } #if BUILDFLAG(IS_WIN) // NOTE: this function is used to set Chrome's open command in the registry // during update. Any change to the syntax must be compatible with the prior // version (i.e., any new syntax must be understood by older browsers expecting // the old syntax, and the new browser must still handle the old syntax), as // old versions are likely to persist, e.g., immediately after background // update, when parsing command lines for other channels, when uninstalling web // applications installed using the old syntax, etc. CommandLine::StringType CommandLine::GetCommandLineStringForShell() const { DCHECK(GetArgs().empty()); StringType command_line_string = GetCommandLineString(); return command_line_string + FILE_PATH_LITERAL(" ") + StringType(kSwitchPrefixes[0]) + kSingleArgument + FILE_PATH_LITERAL(" %1"); } CommandLine::StringType CommandLine::GetCommandLineStringWithUnsafeInsertSequences() const { StringType string(argv_[0]); string = QuoteForCommandLineToArgvW(string, /*allow_unsafe_insert_sequences=*/true); StringType params( GetArgumentsStringInternal(/*allow_unsafe_insert_sequences=*/true)); if (!params.empty()) { string.append(FILE_PATH_LITERAL(" ")); string.append(params); } return string; } #endif // BUILDFLAG(IS_WIN) CommandLine::StringType CommandLine::GetArgumentsString() const { return GetArgumentsStringInternal(/*allow_unsafe_insert_sequences=*/false); } #if BUILDFLAG(IS_WIN) void CommandLine::ParseAsSingleArgument( const CommandLine::StringType& single_arg_switch) { DCHECK(!raw_command_line_string_.empty()); // Remove any previously parsed arguments. argv_.resize(static_cast(begin_args_)); // Locate "--single-argument" in the process's raw command line. Results are // unpredictable if "--single-argument" appears as part of a previous // argument or switch. const size_t single_arg_switch_position = raw_command_line_string_.find(single_arg_switch); DCHECK_NE(single_arg_switch_position, StringType::npos); // Append the portion of the raw command line that starts one character past // "--single-argument" as the one and only argument, or return if no // argument is present. const size_t arg_position = single_arg_switch_position + single_arg_switch.length() + 1; if (arg_position >= raw_command_line_string_.length()) return; const StringPieceType arg = raw_command_line_string_.substr(arg_position); if (!arg.empty()) { AppendArgNative(arg); } } #endif // BUILDFLAG(IS_WIN) } // namespace base