Allow typing label names on Windows by not treating things that start…

… with slashes as arguments rather than switches.

The old command line parsing is still run so some code could get confused later since / will also be treated as a switch if you ask for it. This seems not as likely to happen that the label will match a switch. If it does, we'll have to change the CommandLine class to make the "/" behavior optional.

Fix a "desc" crash attributing blame due to a null pointer.

BUG=
R=scottmg@chromium.org, thakis@chromium.org

Review URL: https://codereview.chromium.org/24613003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225277 0039d316-1c4b-4281-b951-d872f2087c98

base/command_line.cc

@@ -27,17 +27,22 @@ CommandLine* CommandLine::current_process_commandline_ = NULL;
 namespace {
 const CommandLine::CharType kSwitchTerminator[] = FILE_PATH_LITERAL("--");
 const 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 defined(OS_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.
 const CommandLine::CharType* const kSwitchPrefixes[] = {L"--", L"-", L"/"};
 #elif defined(OS_POSIX)
 // Unixes don't use slash as a switch.
 const CommandLine::CharType* const kSwitchPrefixes[] = {"--", "-"};
 #endif
+size_t switch_prefix_count = arraysize(kSwitchPrefixes);
 
 size_t GetSwitchPrefixLength(const CommandLine::StringType& string) {
-  for (size_t i = 0; i < arraysize(kSwitchPrefixes); ++i) {
+  for (size_t i = 0; i < switch_prefix_count; ++i) {
     CommandLine::StringType prefix(kSwitchPrefixes[i]);
     if (string.compare(0, prefix.length(), prefix) == 0)
       return prefix.length();
@@ -169,6 +174,15 @@ CommandLine::CommandLine(const StringVector& argv)
 CommandLine::~CommandLine() {
 }
 
+#if defined(OS_WIN)
+// static
+void CommandLine::set_slash_is_not_a_switch() {
+  // The last switch prefix should be slash, so adjust the size to skip it.
+  DCHECK(wcscmp(kSwitchPrefixes[arraysize(kSwitchPrefixes) - 1], L"/") == 0);
+  switch_prefix_count = arraysize(kSwitchPrefixes) - 1;
+}
+#endif
+
 // static
 bool CommandLine::Init(int argc, const char* const* argv) {
   if (current_process_commandline_) {

base/command_line.h

@@ -53,6 +53,17 @@ class BASE_EXPORT CommandLine {
 
   ~CommandLine();
 
+#if defined(OS_WIN)
+  // By default this class will treat command-line arguments beginning with
+  // slashes as switches on Windows, but not other platforms.
+  //
+  // If this behavior is inappropriate for your application, you can call this
+  // function BEFORE initializing the current process' global command line
+  // object and the behavior will be the same as Posix systems (only hyphens
+  // begin switches, everything else will be an arg).
+  static void set_slash_is_not_a_switch();
+#endif
+
   // Initialize the current process CommandLine singleton. On Windows, ignores
   // its arguments (we instead parse GetCommandLineW() directly) because we
   // don't trust the CRT's parsing of the command line, but it still must be

tools/gn/command_desc.cc

@@ -212,11 +212,11 @@ template<typename T> void OutputRecursiveTargetConfig(
       if (config) {
         // Source of this value is a config.
         out << "  From " << config->label().GetUserVisibleName(false) << "\n";
+        OutputSourceOfDep(target, config->label(), out);
       } else {
         // Source of this value is the target itself.
         out << "  From " << target->label().GetUserVisibleName(false) << "\n";
       }
-      OutputSourceOfDep(target, config->label(), out);
     }
 
     // Actual values.

tools/gn/gn_main.cc

@@ -27,6 +27,9 @@ std::vector<std::string> GetArgs(const CommandLine& cmdline) {
 
 int main(int argc, char** argv) {
   base::AtExitManager at_exit;
+#if defined(OS_WIN)
+  CommandLine::set_slash_is_not_a_switch();
+#endif
   CommandLine::Init(argc, argv);
 
   const CommandLine& cmdline = *CommandLine::ForCurrentProcess();