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diff --git a/specs/geproto.txt b/specs/geproto.txt deleted file mode 100644 index 1054def..0000000 --- a/specs/geproto.txt +++ /dev/null @@ -1,84 +0,0 @@ - X Generic Event Extension - Peter Hutterer - peter.hutterer@who-t.net - - -1. Introduction -2. Extension Initialization -3. Events -4. Notes - -_____________________________________________________________________________ -1. Introduction - -X was designed to provide 64 event opcodes for all extensions. These events -are limited to 32 bytes. - -The Generic Event Extension provides a template event for extensions to re-use -a single event opcode. GE only provide headers and the most basic -functionality, leaving the extensions to interpret the events in their -specific context. - -GenericEvents may be longer than 32 bytes. If so, the number of 4 byte units -following the initial 32 bytes must be specified in the length field of the -event. -_____________________________________________________________________________ -2. Extension Initialization - -The name of this extension is "Generic Event Extension" - -┌─── - GEQueryVersion - client-major-version: CARD16 - client-minor-version: CARD16 - ▶ - major-version: CARD16 - minor-version: CARD16 -└─── - - The client sends the highest supported version to the server - and the server sends the highest version it supports, but no - higher than the requested version. Major versions changes can - introduce incompatibilities in existing functionality, minor - version changes introduce only backward compatible changes. - It is the clients responsibility to ensure that the server - supports a version which is compatible with its expectations. - - - As of version 1.0, no other requests are provided by this extension. -_____________________________________________________________________________ -3. Events - -GE defines a single event, to be used by all extensions. The event's structure -is similar to a reply. This is a core protocol event, ID 35, and is not itself -an extension event. - -┌─── - GenericEvent - type: BYTE; always GenericEvent (35) - extension: CARD8; extension offset - sequenceNumber: CARD16 low 16 bits of request seq. number - length: CARD32 length - evtype: CARD16 event type -└─── - - The field 'extension' is to be set to the major opcode of the - extension. The 'evtype' field is the actual opcode of the event. - The length field specifies the number of 4-byte blocks after the - initial 32 bytes. If length is 0, the event is 32 bytes long. -_____________________________________________________________________________ -4. Notes - -Although the wire event is of arbitrary length, the actual size of an XEvent -is restricted to sizeof(XEvent) [96 bytes, see Xlib.h]. If an extension -converts a wire event to an XEvent > 96 bytes, it will overwrite the space -allocated for the event. See struct _XSQEvent in Xlibint.h for details. - -Extensions need to malloc additional data and fill the XEvent structure with -pointers to the malloc'd data. The client then needs to free the data, only -the XEvent structure will be released by Xlib. - -The server must not send GenericEvents longer than 32 bytes until it has -verified that the client is able to interpret these events. If a long event is -sent to a client unable to process GenericEvents, future interpretation of -replies and events by this client will fail. |