Fix long file paths for Windows

Allows specifying which arguments into aapt2 are file paths.
If the path exceeds the maximum path length for Windows, encode the path using
the extended-length prefix.

Bug: 120853927
Test: aapt2_tests.exe

Change-Id: Ibe5c1cc79a70c33c302157f2ffd54525439a910f
diff --git a/tools/aapt2/cmd/Command.h b/tools/aapt2/cmd/Command.h
index 1694988..d21571d 100644
--- a/tools/aapt2/cmd/Command.h
+++ b/tools/aapt2/cmd/Command.h
@@ -32,55 +32,83 @@
 class Command {
  public:
   explicit Command(const android::StringPiece& name) : name_(name.to_string()),
-                                                       fullname_(name.to_string()) { }
+                                                       short_name_(""),
+                                                       full_subcommand_name_(name.to_string()) {}
+
   explicit Command(const android::StringPiece& name, const android::StringPiece& short_name)
-      : name_(name.to_string()), short_name_(short_name.to_string()), fullname_(name.to_string()) {}
+      : name_(name.to_string()), short_name_(short_name.to_string()),
+        full_subcommand_name_(name.to_string()) {}
+
   virtual ~Command() = default;
 
+  // Behavior flags used with the following functions that change how the command flags are parsed
+  // displayed.
+  enum : uint32_t {
+    // Indicates the arguments are file or folder paths. On Windows, paths that exceed the maximum
+    // path length will be converted to use the extended path prefix '//?/'. Without this
+    // conversion, files with long paths cannot be opened.
+    kPath = 1 << 0,
+  };
+
   void AddRequiredFlag(const android::StringPiece& name, const android::StringPiece& description,
-      std::string* value);
-  void AddRequiredFlagList(const android::StringPiece& name, const android::StringPiece&
-      description, std::vector<std::string>* value);
+                       std::string* value, uint32_t flags = 0);
+
+  void AddRequiredFlagList(const android::StringPiece& name,
+                           const android::StringPiece& description, std::vector<std::string>* value,
+                           uint32_t flags = 0);
+
   void AddOptionalFlag(const android::StringPiece& name, const android::StringPiece& description,
-      Maybe<std::string>* value);
+                       Maybe<std::string>* value, uint32_t flags = 0);
+
   void AddOptionalFlagList(const android::StringPiece& name,
-      const android::StringPiece& description, std::vector<std::string>* value);
+                           const android::StringPiece& description, std::vector<std::string>* value,
+                           uint32_t flags = 0);
+
   void AddOptionalFlagList(const android::StringPiece& name,
-      const android::StringPiece& description, std::unordered_set<std::string>* value);
+                           const android::StringPiece& description,
+                           std::unordered_set<std::string>* value);
+
   void AddOptionalSwitch(const android::StringPiece& name, const android::StringPiece& description,
-      bool* value);
+                         bool* value);
+
   void AddOptionalSubcommand(std::unique_ptr<Command>&& subcommand, bool experimental = false);
 
   void SetDescription(const android::StringPiece& name);
 
-  /** Prints the help menu of the command. */
+  // Prints the help menu of the command.
   void Usage(std::ostream* out);
 
-  /**
-   * Parses the command line arguments, sets the flag variable values, and runs the action of
-   * the command. If the arguments fail to parse to the command and its subcommands, then the action
-   * will not be run and the usage will be printed instead.
-   **/
+  // Parses the command line arguments, sets the flag variable values, and runs the action of
+  // the command. If the arguments fail to parse to the command and its subcommands, then the action
+  // will not be run and the usage will be printed instead.
   int Execute(const std::vector<android::StringPiece>& args, std::ostream* outError);
 
-  /** The action to preform when the command is executed. */
+  // The action to preform when the command is executed.
   virtual int Action(const std::vector<std::string>& args) = 0;
 
  private:
-  struct Flag {
-    std::string name;
-    std::string description;
-    std::function<bool(const android::StringPiece& value)> action;
-    bool required;
-    size_t num_args;
+  DISALLOW_COPY_AND_ASSIGN(Command);
 
-    bool parsed;
+  struct Flag {
+    explicit Flag(const android::StringPiece& name, const android::StringPiece& description,
+                  const bool is_required, const size_t num_args,
+                  std::function<bool(const android::StringPiece& value)>&& action)
+        : name(name.to_string()), description(description.to_string()), is_required(is_required),
+          num_args(num_args), action(std::move(action)) {}
+
+    const std::string name;
+    const std::string description;
+    const bool is_required;
+    const size_t num_args;
+    const std::function<bool(const android::StringPiece& value)> action;
+    bool found = false;
   };
 
-  std::string description_;
-  std::string name_;
-  std::string short_name_;
-  std::string fullname_;
+  const std::string name_;
+  const std::string short_name_;
+  std::string description_ = "";
+  std::string full_subcommand_name_;
+
   std::vector<Flag> flags_;
   std::vector<std::unique_ptr<Command>> subcommands_;
   std::vector<std::unique_ptr<Command>> experimental_subcommands_;