unencrypted_properties.h

   1 #include <string>
   2 #include <fstream>
   3
   4 // key names for properties we use
   5 namespace properties {
   6     extern const char* key;
   7     extern const char* ref;
   8     extern const char* type;
   9     extern const char* password;
  10 }
  11
  12 /**
  13  * Class to store data on the unencrypted folder of a device.
  14  * Note that the folder must exist before this class is constructed.
  15  * All names must be valid single level (no '/') file or directory names
  16  * Data is organized hierarchically so we can get a child folder
  17  */
  18 class UnencryptedProperties
  19 {
  20 public:
  21     // Opens properties folder on named device.
  22     // If folder does not exist, construction will succeed, but all
  23     // getters will return default properties and setters will fail.
  24     UnencryptedProperties(const char* device);
  25
  26     // Get named object. Return default if object does not exist or error.
  27     template<typename t> t Get(const char* name, t default_value = t());
  28
  29     // Set named object. Return true if success, false otherwise
  30     template<typename t> bool Set(const char* name, t const& value);
  31
  32     // Get child properties
  33     UnencryptedProperties GetChild(const char* name);
  34
  35     // Remove named object
  36     bool Remove(const char* name);
  37
  38     // Get path of folder
  39     std::string const& GetPath() const {return folder_;}
  40 private:
  41     UnencryptedProperties();
  42     bool OK() const;
  43     std::string folder_;
  44 };
  45
  46
  47 template<typename t> t UnencryptedProperties::Get(const char* name,
  48                                                   t default_value)
  49 {
  50     if (!OK()) return default_value;
  51     t value = default_value;
  52     std::ifstream(folder_ + "/" + name) >> value;
  53     return value;
  54 }
  55
  56 template<typename t> bool UnencryptedProperties::Set(const char* name,
  57                                                      t const& value)
  58 {
  59     if (!OK()) return false;
  60     std::ofstream o(folder_ + "/" + name);
  61     o << value;
  62     return !o.fail();
  63 }
  64
  65 // Specialized getters/setters for strings
  66 template<> std::string UnencryptedProperties::Get(const char* name,
  67                                       std::string default_value);
  68
  69 template<> bool UnencryptedProperties::Set(const char* name,
  70                                            std::string const& value);