base::CommandLine: Added optional quoting of placeholder arguments.

base/command_line.cc

Index: base/command_line.cc
diff --git a/base/command_line.cc b/base/command_line.cc
index ca4af9754cb07a22268992bee0a79f79ad313fc4..6694cd17da6b650637905413a06ae547667c15c4 100644
--- a/base/command_line.cc
+++ b/base/command_line.cc
@@ -105,10 +105,16 @@ std::string LowerASCIIOnWindows(const std::string& string) {
 
 #if defined(OS_WIN)
 // Quote a string as necessary for CommandLineToArgvW compatiblity *on Windows*.
-std::wstring QuoteForCommandLineToArgvW(const std::wstring& arg) {
+std::wstring QuoteForCommandLineToArgvW(const std::wstring& arg,
+                                        bool quote_placeholders) {
   // We follow the quoting rules of CommandLineToArgvW.
   // http://msdn.microsoft.com/en-us/library/17w5ykft.aspx
-  if (arg.find_first_of(L" \\\"") == std::wstring::npos) {
+  std::wstring quotable_chars(L" \\\"");
+  // We may also be required to quote '%', which is commonly used in a command
+  // line as a placeholder. (It may be substituted for a string with spaces.)
+  if (quote_placeholders)
+    quotable_chars.push_back(L'%');
+  if (arg.find_first_of(quotable_chars) == std::wstring::npos) {
     // No quoting necessary.
     return arg;
   }
@@ -247,12 +253,13 @@ void CommandLine::InitFromArgv(const StringVector& argv) {
   AppendSwitchesAndArguments(*this, argv);
 }
 
-CommandLine::StringType CommandLine::GetCommandLineString() const {
+CommandLine::StringType CommandLine::GetCommandLineString(
+    bool quote_placeholders) const {
   StringType string(argv_[0]);
 #if defined(OS_WIN)
-  string = QuoteForCommandLineToArgvW(string);
+  string = QuoteForCommandLineToArgvW(string, quote_placeholders);
 #endif
-  StringType params(GetArgumentsString());
+  StringType params(GetArgumentsString(quote_placeholders));
   if (!params.empty()) {
     string.append(StringType(FILE_PATH_LITERAL(" ")));
     string.append(params);
@@ -260,7 +267,8 @@ CommandLine::StringType CommandLine::GetCommandLineString() const {
   return string;
 }
 
-CommandLine::StringType CommandLine::GetArgumentsString() const {
+CommandLine::StringType CommandLine::GetArgumentsString(
+    bool quote_placeholders) const {
   StringType params;
   // Append switches and arguments.
   bool parse_switches = true;
@@ -275,14 +283,15 @@ CommandLine::StringType CommandLine::GetArgumentsString() const {
       params.append(switch_string);
       if (!switch_value.empty()) {
 #if defined(OS_WIN)
-        switch_value = QuoteForCommandLineToArgvW(switch_value);
+        switch_value =
+            QuoteForCommandLineToArgvW(switch_value, quote_placeholders);
 #endif
         params.append(kSwitchValueSeparator + switch_value);
       }
     }
     else {
 #if defined(OS_WIN)
-      arg = QuoteForCommandLineToArgvW(arg);
+      arg = QuoteForCommandLineToArgvW(arg, quote_placeholders);
 #endif
       params.append(arg);
     }