dbus/dbus-marshal-recursive.h

   1 /* -*- mode: C; c-file-style: "gnu" -*- */
   2 /* dbus-marshal-recursive.h  Marshalling routines for recursive types
   3  *
   4  * Copyright (C) 2004, 2005 Red Hat, Inc.
   5  *
   6  * Licensed under the Academic Free License version 2.1
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  *
  22  */
  23
  24 #ifndef DBUS_MARSHAL_RECURSIVE_H
  25 #define DBUS_MARSHAL_RECURSIVE_H
  26
  27 #include <config.h>
  28 #include <dbus/dbus-protocol.h>
  29 #include <dbus/dbus-list.h>
  30
  31 #ifndef PACKAGE
  32 #error "config.h not included here"
  33 #endif
  34
  35 typedef struct DBusTypeMark        DBusTypeMark;
  36 typedef struct DBusTypeReader      DBusTypeReader;
  37 typedef struct DBusTypeWriter      DBusTypeWriter;
  38 typedef struct DBusTypeReaderClass DBusTypeReaderClass;
  39 typedef struct DBusArrayLenFixup   DBusArrayLenFixup;
  40
  41 /** The mark is a way to compress a #DBusTypeReader; it isn't all that
  42  * successful though. The idea was to use this for caching header
  43  * fields in dbus-message.c. However now I'm thinking why not cache
  44  * the actual values (e.g. char*) and if the field needs to be set or
  45  * deleted, just linear search for it. Those operations are uncommon,
  46  * and getting the values should be fast and not involve all this type
  47  * reader nonsense.
  48  *
  49  * @todo DBusTypeMark isn't used right now and probably won't be, we should delete it
  50  */
  51 struct DBusTypeMark
  52 {
  53   dbus_uint32_t type_pos_in_value_str : 1; /**< true if the type_pos is in value_str and not type_str */
  54   dbus_uint32_t container_type : 3; /**< the "id" of the container type */
  55   dbus_uint32_t array_len_offset : 3; /**< bytes back from start_pos that len ends */
  56   dbus_uint32_t type_pos : DBUS_MAXIMUM_MESSAGE_LENGTH_BITS; /**< position in type_str */
  57   dbus_uint32_t value_pos : DBUS_MAXIMUM_MESSAGE_LENGTH_BITS; /**< position in value_str */
  58   dbus_uint32_t array_start_pos : DBUS_MAXIMUM_MESSAGE_LENGTH_BITS; /**< start of the array the reader was iterating over */
  59 };
  60
  61 /**
  62  * The type reader is an iterator for reading values from a block of
  63  * values.
  64  */
  65 struct DBusTypeReader
  66 {
  67   dbus_uint32_t byte_order : 8; /**< byte order of the block */
  68
  69   dbus_uint32_t finished : 1;   /**< marks we're at end iterator for cases
  70                                  * where we don't have another way to tell
  71                                  */
  72   dbus_uint32_t array_len_offset : 3; /**< bytes back from start_pos that len ends */
  73   const DBusString *type_str;   /**< string containing signature of block */
  74   int type_pos;                 /**< current position in signature */
  75   const DBusString *value_str;  /**< string containing values of block */
  76   int value_pos;                /**< current position in values */
  77
  78   const DBusTypeReaderClass *klass; /**< the vtable for the reader */
  79   union
  80   {
  81     struct {
  82       int start_pos;                /**< for array readers, the start of the array values */
  83     } array;
  84   } u; /**< class-specific data */
  85 };
  86
  87 /**
  88  * The type writer is an iterator for writing to a block of values.
  89  */
  90 struct DBusTypeWriter
  91 {
  92   dbus_uint32_t byte_order : 8;            /**< byte order to write values with */
  93
  94   dbus_uint32_t container_type : 8;        /**< what are we inside? (e.g. struct, variant, array) */
  95
  96   dbus_uint32_t type_pos_is_expectation : 1; /**< type_pos can be either an insertion point for or an expected next type */
  97
  98   dbus_uint32_t enabled : 1; /**< whether to write values */
  99
 100   DBusString *type_str; /**< where to write typecodes (or read type expectations) */
 101   int type_pos;         /**< current pos in type_str */
 102   DBusString *value_str; /**< where to write values */
 103   int value_pos;         /**< next position to write */
 104
 105   union
 106   {
 107     struct {
 108       int start_pos; /**< position of first element in the array */
 109       int len_pos;   /**< position of length of the array */
 110       int element_type_pos; /**< position of array element type in type_str */
 111     } array;
 112   } u; /**< class-specific data */
 113 };
 114
 115 /**
 116  * When modifying an existing block of values, array lengths may need
 117  * to be adjusted; those adjustments are described by this struct.
 118  */
 119 struct DBusArrayLenFixup
 120 {
 121   int len_pos_in_reader; /**< where the length was in the original block */
 122   int new_len;           /**< the new value of the length in the written-out block */
 123 };
 124
 125 void        _dbus_type_reader_init                      (DBusTypeReader        *reader,
 126                                                          int                    byte_order,
 127                                                          const DBusString      *type_str,
 128                                                          int                    type_pos,
 129                                                          const DBusString      *value_str,
 130                                                          int                    value_pos);
 131 void        _dbus_type_reader_init_from_mark            (DBusTypeReader        *reader,
 132                                                          int                    byte_order,
 133                                                          const DBusString      *type_str,
 134                                                          const DBusString      *value_str,
 135                                                          const DBusTypeMark    *mark);
 136 void        _dbus_type_reader_init_types_only           (DBusTypeReader        *reader,
 137                                                          const DBusString      *type_str,
 138                                                          int                    type_pos);
 139 void        _dbus_type_reader_init_types_only_from_mark (DBusTypeReader        *reader,
 140                                                          const DBusString      *type_str,
 141                                                          const DBusTypeMark    *mark);
 142 void        _dbus_type_reader_save_mark                 (const DBusTypeReader  *reader,
 143                                                          DBusTypeMark          *mark);
 144 int         _dbus_type_reader_get_current_type          (const DBusTypeReader  *reader);
 145 int         _dbus_type_reader_get_element_type          (const DBusTypeReader  *reader);
 146 int         _dbus_type_reader_get_value_pos             (const DBusTypeReader  *reader);
 147 void        _dbus_type_reader_read_basic                (const DBusTypeReader  *reader,
 148                                                          void                  *value);
 149 int         _dbus_type_reader_get_array_length          (const DBusTypeReader  *reader);
 150 void        _dbus_type_reader_read_fixed_multi          (const DBusTypeReader  *reader,
 151                                                          void                  *value,
 152                                                          int                   *n_elements);
 153 void        _dbus_type_reader_read_raw                  (const DBusTypeReader  *reader,
 154                                                          const unsigned char  **value_location);
 155 void        _dbus_type_reader_recurse                   (DBusTypeReader        *reader,
 156                                                          DBusTypeReader        *subreader);
 157 dbus_bool_t _dbus_type_reader_next                      (DBusTypeReader        *reader);
 158 dbus_bool_t _dbus_type_reader_has_next                  (const DBusTypeReader  *reader);
 159 void        _dbus_type_reader_get_signature             (const DBusTypeReader  *reader,
 160                                                          const DBusString     **str_p,
 161                                                          int                   *start_p,
 162                                                          int                   *len_p);
 163 dbus_bool_t _dbus_type_reader_set_basic                 (DBusTypeReader        *reader,
 164                                                          const void            *value,
 165                                                          const DBusTypeReader  *realign_root);
 166 dbus_bool_t _dbus_type_reader_delete                    (DBusTypeReader        *reader,
 167                                                          const DBusTypeReader  *realign_root);
 168 dbus_bool_t _dbus_type_reader_greater_than              (const DBusTypeReader  *lhs,
 169                                                          const DBusTypeReader  *rhs);
 170
 171 dbus_bool_t _dbus_type_reader_equal_values              (const DBusTypeReader *lhs,
 172                                                          const DBusTypeReader *rhs);
 173
 174 void        _dbus_type_signature_next                   (const char            *signature,
 175                                                          int                   *type_pos);
 176
 177 void        _dbus_type_writer_init                 (DBusTypeWriter        *writer,
 178                                                     int                    byte_order,
 179                                                     DBusString            *type_str,
 180                                                     int                    type_pos,
 181                                                     DBusString            *value_str,
 182                                                     int                    value_pos);
 183 void        _dbus_type_writer_init_types_delayed   (DBusTypeWriter        *writer,
 184                                                     int                    byte_order,
 185                                                     DBusString            *value_str,
 186                                                     int                    value_pos);
 187 void        _dbus_type_writer_add_types            (DBusTypeWriter        *writer,
 188                                                     DBusString            *type_str,
 189                                                     int                    type_pos);
 190 void        _dbus_type_writer_remove_types         (DBusTypeWriter        *writer);
 191 void        _dbus_type_writer_init_values_only     (DBusTypeWriter        *writer,
 192                                                     int                    byte_order,
 193                                                     const DBusString      *type_str,
 194                                                     int                    type_pos,
 195                                                     DBusString            *value_str,
 196                                                     int                    value_pos);
 197 dbus_bool_t _dbus_type_writer_write_basic          (DBusTypeWriter        *writer,
 198                                                     int                    type,
 199                                                     const void            *value);
 200 dbus_bool_t _dbus_type_writer_write_fixed_multi    (DBusTypeWriter        *writer,
 201                                                     int                    element_type,
 202                                                     const void            *value,
 203                                                     int                    n_elements);
 204 dbus_bool_t _dbus_type_writer_recurse              (DBusTypeWriter        *writer,
 205                                                     int                    container_type,
 206                                                     const DBusString      *contained_type,
 207                                                     int                    contained_type_start,
 208                                                     DBusTypeWriter        *sub);
 209 dbus_bool_t _dbus_type_writer_unrecurse            (DBusTypeWriter        *writer,
 210                                                     DBusTypeWriter        *sub);
 211 dbus_bool_t _dbus_type_writer_append_array         (DBusTypeWriter        *writer,
 212                                                     const DBusString      *contained_type,
 213                                                     int                    contained_type_start,
 214                                                     DBusTypeWriter        *sub);
 215 dbus_bool_t _dbus_type_writer_write_reader         (DBusTypeWriter        *writer,
 216                                                     DBusTypeReader        *reader);
 217 dbus_bool_t _dbus_type_writer_write_reader_partial (DBusTypeWriter        *writer,
 218                                                     DBusTypeReader        *reader,
 219                                                     const DBusTypeReader  *start_after,
 220                                                     int                    start_after_new_pos,
 221                                                     int                    start_after_new_len,
 222                                                     DBusList             **fixups);
 223 void        _dbus_type_writer_set_enabled          (DBusTypeWriter        *writer,
 224                                                     dbus_bool_t            enabled);
 225
 226
 227 #endif /* DBUS_MARSHAL_RECURSIVE_H */