Warning, /frameworks/kded/docs/DESIGN is written in an unsupported language. File is not indexed.
0001 kded
0002 ====
0003
0004 kded is responsible for creating the sycoca file, i.e. the binary
0005 cache of servicetypes, mimetypes, and services for a particular user.
0006
0007 It uses KDirWatch to monitor the directories containing .desktop files.
0008 When a file is added/removed, it waits 5 seconds (in case of series of
0009 updates), and then launches kbuildsycoca.
0010
0011 kbuildsycoca recreates the sycoca file by:
0012 * parsing all .desktop files, replacing global ones by local ones (at any
0013 level of the hierarchy)
0014 * creating all objects in memory
0015 * saving everything in the sycoca file (see below for ksycoca internals)
0016 * clearing all memory
0017 * notifying the applications that use ksycoca by a DBUS signal emitted to
0018 the ksycoca object (KSycoca::notifyDatabaseChanged()).
0019
0020 Format of the sycoca database file
0021 ==================================
0022
0023 * Version
0024
0025 List of factories
0026 | * Factory id, Factory offset
0027 | * Factory id, Factory offset
0028 | * ...
0029 | * 0
0030
0031 * KDE prefixes
0032 * timestamp
0033 * KDE language
0034 * resource hash
0035 * list of all resource dirs
0036
0037 For each factory
0038 | Header
0039 | * offset of the dict
0040 | * offset of the beginning of the entries
0041 | * offset of the end of the entries
0042 | Rest of the header (factory-specific), for instance:
0043 | * Offer-list offset
0044 | * Mimetype-patterns index offset (fast patterns)
0045 | * Mimetype-patterns index offset (other)
0046 | * Entry size in the mimetype-patterns index ("fast" part)
0047 |
0048 | KSycocaEntries
0049 | | * entry type
0050 | | Entry
0051 | | | entry-dependent information
0052 | | ...
0053 | |
0054 | Dict
0055 | | * hashtable size
0056 | | Hash list
0057 | | | * list of values used to compute a hash key
0058 | | Hash table
0059 | | | * id (positive = entry offset)
0060 | | | * id (negative = - offset in duplicates list )
0061 | | | * 0 if no entry for that hash value
0062 | | Table of duplicates
0063 | | | * entry offset, key
0064 | | | * entry offset, key
0065 |
0066
0067 Offer list
0068 | * servicetype offset, service offset
0069 | * servicetype offset, service offset
0070 | * servicetype offset, service offset
0071 | * servicetype offset, service offset
0072 | * mimetype offset, service offset
0073 | * mimetype offset, service offset
0074 | * mimetype offset, service offset
0075 | * mimetype offset, service offset
0076 | * 0
0077 This allows to quickly find services associated with a servicetype.
0078 It does NOT reflect the user profile, which is stored in profilerc and
0079 implemented in KServiceTypeProfile.
0080
0081 Mimetype patterns
0082 | Fast patterns (fixed size)
0083 | * Extension (padded to 4 chars), mimetype offset
0084 | * Extension (padded to 4 chars), mimetype offset
0085 | * Extension (padded to 4 chars), mimetype offset
0086 | Other patterns (variable size)
0087 | * Pattern (ex : *.*gf), mimetype offset
0088 | * Pattern (ex : Makefile*), mimetype offset
0089 | * ""
0090
0091 The first one is designed for a binary search, since entries have a fixed size
0092 and are sorted by extension.
0093 The second one (10% of the mimetypes usually) is for a linear search.