Home | History | Annotate | Download | only in base 
      1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #include "base/command_line.h"
      6 
      7 #include <algorithm>
      8 #include <ostream>
      9 
     10 #include "base/files/file_path.h"
     11 #include "base/logging.h"
     12 #include "base/macros.h"
     13 #include "base/strings/string_split.h"
     14 #include "base/strings/string_util.h"
     15 #include "base/strings/utf_string_conversions.h"
     16 #include "build/build_config.h"
     17 
     18 #if defined(OS_WIN)
     19 #include <windows.h>
     20 #include <shellapi.h>
     21 #endif
     22 
     23 namespace base {
     24 
     25 CommandLine* CommandLine::current_process_commandline_ = NULL;
     26 
     27 namespace {
     28 
     29 const CommandLine::CharType kSwitchTerminator[] = FILE_PATH_LITERAL("--");
     30 const CommandLine::CharType kSwitchValueSeparator[] = FILE_PATH_LITERAL("=");
     31 
     32 // Since we use a lazy match, make sure that longer versions (like "--") are
     33 // listed before shorter versions (like "-") of similar prefixes.
     34 #if defined(OS_WIN)
     35 // By putting slash last, we can control whether it is treaded as a switch
     36 // value by changing the value of switch_prefix_count to be one less than
     37 // the array size.
     38 const CommandLine::CharType* const kSwitchPrefixes[] = {L"--", L"-", L"/"};
     39 #elif defined(OS_POSIX)
     40 // Unixes don't use slash as a switch.
     41 const CommandLine::CharType* const kSwitchPrefixes[] = {"--", "-"};
     42 #endif
     43 size_t switch_prefix_count = arraysize(kSwitchPrefixes);
     44 
     45 size_t GetSwitchPrefixLength(const CommandLine::StringType& string) {
     46   for (size_t i = 0; i < switch_prefix_count; ++i) {
     47     CommandLine::StringType prefix(kSwitchPrefixes[i]);
     48     if (string.compare(0, prefix.length(), prefix) == 0)
     49       return prefix.length();
     50   }
     51   return 0;
     52 }
     53 
     54 // Fills in |switch_string| and |switch_value| if |string| is a switch.
     55 // This will preserve the input switch prefix in the output |switch_string|.
     56 bool IsSwitch(const CommandLine::StringType& string,
     57               CommandLine::StringType* switch_string,
     58               CommandLine::StringType* switch_value) {
     59   switch_string->clear();
     60   switch_value->clear();
     61   size_t prefix_length = GetSwitchPrefixLength(string);
     62   if (prefix_length == 0 || prefix_length == string.length())
     63     return false;
     64 
     65   const size_t equals_position = string.find(kSwitchValueSeparator);
     66   *switch_string = string.substr(0, equals_position);
     67   if (equals_position != CommandLine::StringType::npos)
     68     *switch_value = string.substr(equals_position + 1);
     69   return true;
     70 }
     71 
     72 // Append switches and arguments, keeping switches before arguments.
     73 void AppendSwitchesAndArguments(CommandLine* command_line,
     74                                 const CommandLine::StringVector& argv) {
     75   bool parse_switches = true;
     76   for (size_t i = 1; i < argv.size(); ++i) {
     77     CommandLine::StringType arg = argv[i];
     78 #if defined(OS_WIN)
     79     TrimWhitespace(arg, TRIM_ALL, &arg);
     80 #else
     81     TrimWhitespaceASCII(arg, TRIM_ALL, &arg);
     82 #endif
     83 
     84     CommandLine::StringType switch_string;
     85     CommandLine::StringType switch_value;
     86     parse_switches &= (arg != kSwitchTerminator);
     87     if (parse_switches && IsSwitch(arg, &switch_string, &switch_value)) {
     88 #if defined(OS_WIN)
     89       command_line->AppendSwitchNative(UTF16ToASCII(switch_string),
     90                                        switch_value);
     91 #elif defined(OS_POSIX)
     92       command_line->AppendSwitchNative(switch_string, switch_value);
     93 #endif
     94     } else {
     95       command_line->AppendArgNative(arg);
     96     }
     97   }
     98 }
     99 
    100 #if defined(OS_WIN)
    101 // Quote a string as necessary for CommandLineToArgvW compatiblity *on Windows*.
    102 string16 QuoteForCommandLineToArgvW(const string16& arg,
    103                                     bool quote_placeholders) {
    104   // We follow the quoting rules of CommandLineToArgvW.
    105   // http://msdn.microsoft.com/en-us/library/17w5ykft.aspx
    106   string16 quotable_chars(L" \\\"");
    107   // We may also be required to quote '%', which is commonly used in a command
    108   // line as a placeholder. (It may be substituted for a string with spaces.)
    109   if (quote_placeholders)
    110     quotable_chars.push_back(L'%');
    111   if (arg.find_first_of(quotable_chars) == string16::npos) {
    112     // No quoting necessary.
    113     return arg;
    114   }
    115 
    116   string16 out;
    117   out.push_back(L'"');
    118   for (size_t i = 0; i < arg.size(); ++i) {
    119     if (arg[i] == '\\') {
    120       // Find the extent of this run of backslashes.
    121       size_t start = i, end = start + 1;
    122       for (; end < arg.size() && arg[end] == '\\'; ++end) {}
    123       size_t backslash_count = end - start;
    124 
    125       // Backslashes are escapes only if the run is followed by a double quote.
    126       // Since we also will end the string with a double quote, we escape for
    127       // either a double quote or the end of the string.
    128       if (end == arg.size() || arg[end] == '"') {
    129         // To quote, we need to output 2x as many backslashes.
    130         backslash_count *= 2;
    131       }
    132       for (size_t j = 0; j < backslash_count; ++j)
    133         out.push_back('\\');
    134 
    135       // Advance i to one before the end to balance i++ in loop.
    136       i = end - 1;
    137     } else if (arg[i] == '"') {
    138       out.push_back('\\');
    139       out.push_back('"');
    140     } else {
    141       out.push_back(arg[i]);
    142     }
    143   }
    144   out.push_back('"');
    145 
    146   return out;
    147 }
    148 #endif
    149 
    150 }  // namespace
    151 
    152 CommandLine::CommandLine(NoProgram) : argv_(1), begin_args_(1) {}
    153 
    154 CommandLine::CommandLine(const FilePath& program)
    155     : argv_(1),
    156       begin_args_(1) {
    157   SetProgram(program);
    158 }
    159 
    160 CommandLine::CommandLine(int argc, const CommandLine::CharType* const* argv)
    161     : argv_(1),
    162       begin_args_(1) {
    163   InitFromArgv(argc, argv);
    164 }
    165 
    166 CommandLine::CommandLine(const StringVector& argv)
    167     : argv_(1),
    168       begin_args_(1) {
    169   InitFromArgv(argv);
    170 }
    171 
    172 CommandLine::CommandLine(const CommandLine& other)
    173     : argv_(other.argv_),
    174       switches_(other.switches_),
    175       begin_args_(other.begin_args_) {
    176   ResetStringPieces();
    177 }
    178 
    179 CommandLine& CommandLine::operator=(const CommandLine& other) {
    180   argv_ = other.argv_;
    181   switches_ = other.switches_;
    182   begin_args_ = other.begin_args_;
    183   ResetStringPieces();
    184   return *this;
    185 }
    186 
    187 CommandLine::~CommandLine() {
    188 }
    189 
    190 #if defined(OS_WIN)
    191 // static
    192 void CommandLine::set_slash_is_not_a_switch() {
    193   // The last switch prefix should be slash, so adjust the size to skip it.
    194   DCHECK_EQ(wcscmp(kSwitchPrefixes[arraysize(kSwitchPrefixes) - 1], L"/"), 0);
    195   switch_prefix_count = arraysize(kSwitchPrefixes) - 1;
    196 }
    197 
    198 // static
    199 void CommandLine::InitUsingArgvForTesting(int argc, const char* const* argv) {
    200   DCHECK(!current_process_commandline_);
    201   current_process_commandline_ = new CommandLine(NO_PROGRAM);
    202   // On Windows we need to convert the command line arguments to string16.
    203   base::CommandLine::StringVector argv_vector;
    204   for (int i = 0; i < argc; ++i)
    205     argv_vector.push_back(UTF8ToUTF16(argv[i]));
    206   current_process_commandline_->InitFromArgv(argv_vector);
    207 }
    208 #endif
    209 
    210 // static
    211 bool CommandLine::Init(int argc, const char* const* argv) {
    212   if (current_process_commandline_) {
    213     // If this is intentional, Reset() must be called first. If we are using
    214     // the shared build mode, we have to share a single object across multiple
    215     // shared libraries.
    216     return false;
    217   }
    218 
    219   current_process_commandline_ = new CommandLine(NO_PROGRAM);
    220 #if defined(OS_WIN)
    221   current_process_commandline_->ParseFromString(::GetCommandLineW());
    222 #elif defined(OS_POSIX)
    223   current_process_commandline_->InitFromArgv(argc, argv);
    224 #endif
    225 
    226   return true;
    227 }
    228 
    229 // static
    230 void CommandLine::Reset() {
    231   DCHECK(current_process_commandline_);
    232   delete current_process_commandline_;
    233   current_process_commandline_ = NULL;
    234 }
    235 
    236 // static
    237 CommandLine* CommandLine::ForCurrentProcess() {
    238   DCHECK(current_process_commandline_);
    239   return current_process_commandline_;
    240 }
    241 
    242 // static
    243 bool CommandLine::InitializedForCurrentProcess() {
    244   return !!current_process_commandline_;
    245 }
    246 
    247 #if defined(OS_WIN)
    248 // static
    249 CommandLine CommandLine::FromString(const string16& command_line) {
    250   CommandLine cmd(NO_PROGRAM);
    251   cmd.ParseFromString(command_line);
    252   return cmd;
    253 }
    254 #endif
    255 
    256 void CommandLine::InitFromArgv(int argc,
    257                                const CommandLine::CharType* const* argv) {
    258   StringVector new_argv;
    259   for (int i = 0; i < argc; ++i)
    260     new_argv.push_back(argv[i]);
    261   InitFromArgv(new_argv);
    262 }
    263 
    264 void CommandLine::InitFromArgv(const StringVector& argv) {
    265   argv_ = StringVector(1);
    266   switches_.clear();
    267   switches_by_stringpiece_.clear();
    268   begin_args_ = 1;
    269   SetProgram(argv.empty() ? FilePath() : FilePath(argv[0]));
    270   AppendSwitchesAndArguments(this, argv);
    271 }
    272 
    273 FilePath CommandLine::GetProgram() const {
    274   return FilePath(argv_[0]);
    275 }
    276 
    277 void CommandLine::SetProgram(const FilePath& program) {
    278 #if defined(OS_WIN)
    279   TrimWhitespace(program.value(), TRIM_ALL, &argv_[0]);
    280 #else
    281   TrimWhitespaceASCII(program.value(), TRIM_ALL, &argv_[0]);
    282 #endif
    283 }
    284 
    285 bool CommandLine::HasSwitch(const base::StringPiece& switch_string) const {
    286   DCHECK_EQ(ToLowerASCII(switch_string), switch_string);
    287   return switches_by_stringpiece_.find(switch_string) !=
    288          switches_by_stringpiece_.end();
    289 }
    290 
    291 bool CommandLine::HasSwitch(const char switch_constant[]) const {
    292   return HasSwitch(base::StringPiece(switch_constant));
    293 }
    294 
    295 std::string CommandLine::GetSwitchValueASCII(
    296     const base::StringPiece& switch_string) const {
    297   StringType value = GetSwitchValueNative(switch_string);
    298   if (!IsStringASCII(value)) {
    299     DLOG(WARNING) << "Value of switch (" << switch_string << ") must be ASCII.";
    300     return std::string();
    301   }
    302 #if defined(OS_WIN)
    303   return UTF16ToASCII(value);
    304 #else
    305   return value;
    306 #endif
    307 }
    308 
    309 FilePath CommandLine::GetSwitchValuePath(
    310     const base::StringPiece& switch_string) const {
    311   return FilePath(GetSwitchValueNative(switch_string));
    312 }
    313 
    314 CommandLine::StringType CommandLine::GetSwitchValueNative(
    315     const base::StringPiece& switch_string) const {
    316   DCHECK_EQ(ToLowerASCII(switch_string), switch_string);
    317   auto result = switches_by_stringpiece_.find(switch_string);
    318   return result == switches_by_stringpiece_.end() ? StringType()
    319                                                   : *(result->second);
    320 }
    321 
    322 void CommandLine::AppendSwitch(const std::string& switch_string) {
    323   AppendSwitchNative(switch_string, StringType());
    324 }
    325 
    326 void CommandLine::AppendSwitchPath(const std::string& switch_string,
    327                                    const FilePath& path) {
    328   AppendSwitchNative(switch_string, path.value());
    329 }
    330 
    331 void CommandLine::AppendSwitchNative(const std::string& switch_string,
    332                                      const CommandLine::StringType& value) {
    333 #if defined(OS_WIN)
    334   const std::string switch_key = ToLowerASCII(switch_string);
    335   StringType combined_switch_string(ASCIIToUTF16(switch_key));
    336 #elif defined(OS_POSIX)
    337   const std::string& switch_key = switch_string;
    338   StringType combined_switch_string(switch_key);
    339 #endif
    340   size_t prefix_length = GetSwitchPrefixLength(combined_switch_string);
    341   auto insertion =
    342       switches_.insert(make_pair(switch_key.substr(prefix_length), value));
    343   if (!insertion.second)
    344     insertion.first->second = value;
    345   switches_by_stringpiece_[insertion.first->first] = &(insertion.first->second);
    346   // Preserve existing switch prefixes in |argv_|; only append one if necessary.
    347   if (prefix_length == 0)
    348     combined_switch_string = kSwitchPrefixes[0] + combined_switch_string;
    349   if (!value.empty())
    350     combined_switch_string += kSwitchValueSeparator + value;
    351   // Append the switch and update the switches/arguments divider |begin_args_|.
    352   argv_.insert(argv_.begin() + begin_args_++, combined_switch_string);
    353 }
    354 
    355 void CommandLine::AppendSwitchASCII(const std::string& switch_string,
    356                                     const std::string& value_string) {
    357 #if defined(OS_WIN)
    358   AppendSwitchNative(switch_string, ASCIIToUTF16(value_string));
    359 #elif defined(OS_POSIX)
    360   AppendSwitchNative(switch_string, value_string);
    361 #endif
    362 }
    363 
    364 void CommandLine::CopySwitchesFrom(const CommandLine& source,
    365                                    const char* const switches[],
    366                                    size_t count) {
    367   for (size_t i = 0; i < count; ++i) {
    368     if (source.HasSwitch(switches[i]))
    369       AppendSwitchNative(switches[i], source.GetSwitchValueNative(switches[i]));
    370   }
    371 }
    372 
    373 CommandLine::StringVector CommandLine::GetArgs() const {
    374   // Gather all arguments after the last switch (may include kSwitchTerminator).
    375   StringVector args(argv_.begin() + begin_args_, argv_.end());
    376   // Erase only the first kSwitchTerminator (maybe "--" is a legitimate page?)
    377   StringVector::iterator switch_terminator =
    378       std::find(args.begin(), args.end(), kSwitchTerminator);
    379   if (switch_terminator != args.end())
    380     args.erase(switch_terminator);
    381   return args;
    382 }
    383 
    384 void CommandLine::AppendArg(const std::string& value) {
    385 #if defined(OS_WIN)
    386   DCHECK(IsStringUTF8(value));
    387   AppendArgNative(UTF8ToWide(value));
    388 #elif defined(OS_POSIX)
    389   AppendArgNative(value);
    390 #endif
    391 }
    392 
    393 void CommandLine::AppendArgPath(const FilePath& path) {
    394   AppendArgNative(path.value());
    395 }
    396 
    397 void CommandLine::AppendArgNative(const CommandLine::StringType& value) {
    398   argv_.push_back(value);
    399 }
    400 
    401 void CommandLine::AppendArguments(const CommandLine& other,
    402                                   bool include_program) {
    403   if (include_program)
    404     SetProgram(other.GetProgram());
    405   AppendSwitchesAndArguments(this, other.argv());
    406 }
    407 
    408 void CommandLine::PrependWrapper(const CommandLine::StringType& wrapper) {
    409   if (wrapper.empty())
    410     return;
    411   // The wrapper may have embedded arguments (like "gdb --args"). In this case,
    412   // we don't pretend to do anything fancy, we just split on spaces.
    413   StringVector wrapper_argv = SplitString(
    414       wrapper, FilePath::StringType(1, ' '), base::TRIM_WHITESPACE,
    415       base::SPLIT_WANT_ALL);
    416   // Prepend the wrapper and update the switches/arguments |begin_args_|.
    417   argv_.insert(argv_.begin(), wrapper_argv.begin(), wrapper_argv.end());
    418   begin_args_ += wrapper_argv.size();
    419 }
    420 
    421 #if defined(OS_WIN)
    422 void CommandLine::ParseFromString(const string16& command_line) {
    423   string16 command_line_string;
    424   TrimWhitespace(command_line, TRIM_ALL, &command_line_string);
    425   if (command_line_string.empty())
    426     return;
    427 
    428   int num_args = 0;
    429   wchar_t** args = NULL;
    430   args = ::CommandLineToArgvW(command_line_string.c_str(), &num_args);
    431 
    432   DPLOG_IF(FATAL, !args) << "CommandLineToArgvW failed on command line: "
    433                          << UTF16ToUTF8(command_line);
    434   InitFromArgv(num_args, args);
    435   LocalFree(args);
    436 }
    437 #endif
    438 
    439 CommandLine::StringType CommandLine::GetCommandLineStringInternal(
    440     bool quote_placeholders) const {
    441   StringType string(argv_[0]);
    442 #if defined(OS_WIN)
    443   string = QuoteForCommandLineToArgvW(string, quote_placeholders);
    444 #endif
    445   StringType params(GetArgumentsStringInternal(quote_placeholders));
    446   if (!params.empty()) {
    447     string.append(StringType(FILE_PATH_LITERAL(" ")));
    448     string.append(params);
    449   }
    450   return string;
    451 }
    452 
    453 CommandLine::StringType CommandLine::GetArgumentsStringInternal(
    454     bool quote_placeholders) const {
    455 #if !defined(OS_WIN)
    456   (void)quote_placeholders;  // Avoid an unused warning.
    457 #endif
    458   StringType params;
    459   // Append switches and arguments.
    460   bool parse_switches = true;
    461   for (size_t i = 1; i < argv_.size(); ++i) {
    462     StringType arg = argv_[i];
    463     StringType switch_string;
    464     StringType switch_value;
    465     parse_switches &= arg != kSwitchTerminator;
    466     if (i > 1)
    467       params.append(StringType(FILE_PATH_LITERAL(" ")));
    468     if (parse_switches && IsSwitch(arg, &switch_string, &switch_value)) {
    469       params.append(switch_string);
    470       if (!switch_value.empty()) {
    471 #if defined(OS_WIN)
    472         switch_value =
    473             QuoteForCommandLineToArgvW(switch_value, quote_placeholders);
    474 #endif
    475         params.append(kSwitchValueSeparator + switch_value);
    476       }
    477     } else {
    478 #if defined(OS_WIN)
    479       arg = QuoteForCommandLineToArgvW(arg, quote_placeholders);
    480 #endif
    481       params.append(arg);
    482     }
    483   }
    484   return params;
    485 }
    486 
    487 void CommandLine::ResetStringPieces() {
    488   switches_by_stringpiece_.clear();
    489   for (const auto& entry : switches_)
    490     switches_by_stringpiece_[entry.first] = &(entry.second);
    491 }
    492 
    493 }  // namespace base
    494