m_property.h

   1 /*
   2  * This file is part of MPlayer.
   3  *
   4  * MPlayer is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * MPlayer is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #ifndef MPLAYER_M_PROPERTY_H
  20 #define MPLAYER_M_PROPERTY_H
  21
  22 #include "m_option.h"
  23
  24 /// \defgroup Properties
  25 ///
  26 /// Properties provide an interface to query and set the state of various
  27 /// things in MPlayer. The API is based on the \ref Options API like the
  28 /// \ref Config, but instead of using variables, properties use an ioctl like
  29 /// function. The function is used to perform various actions like get and set
  30 /// (see \ref PropertyActions).
  31 ///@{
  32
  33 /// \file
  34
  35 /// \defgroup PropertyActions Property actions
  36 /// \ingroup Properties
  37 ///@{
  38
  39 /// Get the current value.
  40 /** \param arg Pointer to a variable of the right type.
  41  */
  42 #define M_PROPERTY_GET         0
  43
  44 /// Get a string representing the current value.
  45 /** Set the variable to a newly allocated string or NULL.
  46  *  \param arg Pointer to a char* variable.
  47  */
  48 #define M_PROPERTY_PRINT       1
  49
  50 /// Set a new value.
  51 /** The variable is updated to the value actually set.
  52  *  \param arg Pointer to a variable of the right type.
  53  */
  54 #define M_PROPERTY_SET         2
  55
  56 /// Set a new value from a string.
  57 /** \param arg String containing the value.
  58  */
  59 #define M_PROPERTY_PARSE       3
  60
  61 /*
  62  *  \param arg Pointer to a variable of the right type or NULL.
  63  */
  64 #define M_PROPERTY_STEP        4
  65
  66 /// Get a string containg a parsable representation.
  67 /** Set the variable to a newly allocated string or NULL.
  68  *  \param arg Pointer to a char* variable.
  69  */
  70 #define M_PROPERTY_TO_STRING   6
  71
  72 /// Pass down an action to a sub-property.
  73 #define M_PROPERTY_KEY_ACTION  7
  74
  75 /// Get a m_option describing the property.
  76 #define M_PROPERTY_GET_TYPE    8
  77
  78 ///@}
  79
  80 /// \defgroup PropertyActionsArg Property actions argument type
  81 /// \ingroup Properties
  82 /// \brief  Types used as action argument.
  83 ///@{
  84
  85 /// Argument for \ref M_PROPERTY_KEY_ACTION
  86 typedef struct {
  87     const char* key;
  88     int action;
  89     void* arg;
  90 } m_property_action_t;
  91
  92 ///@}
  93
  94 /// \defgroup PropertyActionsReturn Property actions return code
  95 /// \ingroup Properties
  96 /// \brief  Return values for the control function.
  97 ///@{
  98
  99 /// Returned on success.
 100 #define M_PROPERTY_OK                1
 101
 102 /// Returned on error.
 103 #define M_PROPERTY_ERROR             0
 104
 105 /// \brief Returned when the property can't be used, for example something about
 106 /// the subs while playing audio only
 107 #define M_PROPERTY_UNAVAILABLE      -1
 108
 109 /// Returned if the requested action is not implemented.
 110 #define M_PROPERTY_NOT_IMPLEMENTED  -2
 111
 112 /// Returned when asking for a property that doesn't exist.
 113 #define M_PROPERTY_UNKNOWN          -3
 114
 115 /// Returned when the action can't be done (like setting the volume when edl mute).
 116 #define M_PROPERTY_DISABLED         -4
 117
 118 ///@}
 119
 120 /// \ingroup Properties
 121 /// \brief Property action callback.
 122 typedef int(*m_property_ctrl_f)(const m_option_t* prop,int action,void* arg,void *ctx);
 123
 124 /// Do an action on a property.
 125 /** \param prop_list The list of properties.
 126  *  \param prop The path of the property.
 127  *  \param action See \ref PropertyActions.
 128  *  \param arg Argument, usually a pointer to the data type used by the property.
 129  *  \return See \ref PropertyActionsReturn.
 130  */
 131 int m_property_do(const m_option_t* prop_list, const char* prop,
 132                   int action, void* arg, void *ctx);
 133
 134 /// Print a list of properties.
 135 void m_properties_print_help_list(const m_option_t* list);
 136
 137 /// Expand a property string.
 138 /** This function allows to print strings containing property values.
 139  *  ${NAME} is expanded to the value of property NAME or an empty
 140  *  string in case of error. $(NAME:STR) expand STR only if the property
 141  *  NAME is available.
 142  *
 143  *  \param prop_list An array of \ref m_option describing the available
 144  *                   properties.
 145  *  \param str The string to expand.
 146  *  \return The newly allocated expanded string.
 147  */
 148 char* m_properties_expand_string(const m_option_t* prop_list,char* str, void *ctx);
 149
 150 // Helpers to use MPlayer's properties
 151
 152 /// Do an action with an MPlayer property.
 153 int mp_property_do(const char* name,int action, void* val, void *ctx);
 154
 155 /// Get the value of a property as a string suitable for display in an UI.
 156 char* mp_property_print(const char *name, void* ctx);
 157
 158 /// \defgroup PropertyImplHelper Property implementation helpers
 159 /// \ingroup Properties
 160 /// \brief Helper functions for common property types.
 161 ///@{
 162
 163 /// Clamp a value according to \ref m_option::min and \ref m_option::max.
 164 #define M_PROPERTY_CLAMP(prop,val) do {                                 \
 165         if(((prop)->flags & M_OPT_MIN) && (val) < (prop)->min)          \
 166             (val) = (prop)->min;                                        \
 167         else if(((prop)->flags & M_OPT_MAX) && (val) > (prop)->max)     \
 168             (val) = (prop)->max;                                        \
 169     } while(0)
 170
 171 /// Implement get.
 172 int m_property_int_ro(const m_option_t* prop,int action,
 173                       void* arg,int var);
 174
 175 /// Implement set, get and step up/down.
 176 int m_property_int_range(const m_option_t* prop,int action,
 177                          void* arg,int* var);
 178
 179 /// Same as m_property_int_range but cycle.
 180 int m_property_choice(const m_option_t* prop,int action,
 181                       void* arg,int* var);
 182
 183 int m_property_flag_ro(const m_option_t* prop,int action,
 184                     void* arg,int var);
 185
 186 /// Switch betwen min and max.
 187 int m_property_flag(const m_option_t* prop,int action,
 188                     void* arg,int* var);
 189
 190 /// Implement get, print.
 191 int m_property_float_ro(const m_option_t* prop,int action,
 192                         void* arg,float var);
 193
 194 /// Implement set, get and step up/down
 195 int m_property_float_range(const m_option_t* prop,int action,
 196                            void* arg,float* var);
 197
 198 /// float with a print function which print the time in ms
 199 int m_property_delay(const m_option_t* prop,int action,
 200                      void* arg,float* var);
 201
 202 /// Implement get, print
 203 int m_property_double_ro(const m_option_t* prop,int action,
 204                          void* arg,double var);
 205
 206 /// Implement print
 207 int m_property_time_ro(const m_option_t* prop,int action,
 208                        void* arg,double var);
 209
 210 /// get/print the string
 211 int m_property_string_ro(const m_option_t* prop,int action,void* arg, char* str);
 212
 213 /// get/print a bitrate
 214 int m_property_bitrate(const m_option_t* prop,int action,void* arg,int rate);
 215
 216 ///@}
 217
 218 ///@}
 219
 220 #endif /* MPLAYER_M_PROPERTY_H */