/* $XConsortium: lbxdata.h,v 1.9 94/12/01 20:49:17 mor Exp $ */ /* * Copyright 1994 Network Computing Devices, Inc. * * Permission to use, copy, modify, distribute, and sell this software and * its documentation for any purpose is hereby granted without fee, provided * that the above copyright notice appear in all copies and that both that * copyright notice and this permission notice appear in supporting * documentation, and that the name Network Computing Devices, Inc. not be * used in advertising or publicity pertaining to distribution of this * software without specific, written prior permission. * * THIS SOFTWARE IS PROVIDED `AS-IS'. NETWORK COMPUTING DEVICES, INC., * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING WITHOUT * LIMITATION ALL IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE, OR NONINFRINGEMENT. IN NO EVENT SHALL NETWORK * COMPUTING DEVICES, INC., BE LIABLE FOR ANY DAMAGES WHATSOEVER, INCLUDING * SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES, INCLUDING LOSS OF USE, DATA, * OR PROFITS, EVEN IF ADVISED OF THE POSSIBILITY THEREOF, AND REGARDLESS OF * WHETHER IN AN ACTION IN CONTRACT, TORT OR NEGLIGENCE, ARISING OUT OF OR IN * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * * $NCDId: @(#)lbxdata.h,v 1.23 1994/11/29 22:14:02 lemke Exp $ * * Author: Dave Lemke, Network Computing Devices */ #ifndef _LBXDATA_H_ #define _LBXDATA_H_ #include /* for X typedefs */ #define NEED_REPLIES #include /* for X typedefs */ #include "os.h" #include "atomcache.h" #define _XLBX_SERVER_ #include "lbxstr.h" /* cache stuff */ #define MAX_ATOM_LENGTH 256 /* screw any large ones */ #define MAX_COLORNAME_LENGTH 256 /* screw any large ones */ /* * Notes on request short-circuiting * * X guarentees that any replies, events or errors generated by a * previous request will be sent before those of a later request. * this means that any requests that can be handled by the proxy * must have their reply sent after any previous events or errors. * * there are 3 possible stages implemented here: * * - fully correct protocol, where nothing can be out of order * - mostly correct protocol, where only errors can be out of order * - poor protocol, where events & errors can be out of order * * for most applications, poor is 'good enough', because they don't * depend on events coming in order, and instead let Xlib do * the work. * * depending on the type of protocol being used, the cache_safe * flag in the ClientRec will be set appropriately, and if TRUE, * the proxy is cleared to short-circuit a request. * * for full correct protocol, the flag is set if the previous request * was a round trip and the reply has come back. * * for a mostly correct protocol, the flag is set for the above * case, and for requests that can generate only errors (mostly * graphics) * * for a 'good enough' protocol, the flag is always on, and we let * the client sort things out. * * (note than in no case do we allow replies to come out of order.) * * * Note on Xlib's handling of sequences: * * Xlib usually waits for the reply to sync request before * issuing another -- its archetecture depends on it. However, * this is not required. Xlib itself misses this in at least one * case (XGetWindowAttributes, which uses both the GetWindowAttributes * and GetGeometry requests). * * The upshot is that the proxy has to be able to handle seeing * another request before it receives an expected reply. * * this means we can't assume a single pending reply, but many. * currently these get tacked onto a list. * * * Notes on how the proxy attempts to solve all of this: * * There are 4 request that it will attempt to short-circuit: * InternAtom, GetAtomName, LookupColor, AllocColor, and AllocNamedColor. * All the code to do this is in lbxfuncs.c, and all of it works in * essentially the same way -- whenever possible, it will try to respond * to the client without sending the request all the way to the X server. * The goal is to remove a roudn-trip entirely -- even though not a lot of data * is involved, remving the roundtrip can make this useful. * Unfortunately, figuring out *when* its safe is very nasty. First * there are all the possibile stages outlined above. If the proxy * isn't waiting, thinking there might be pending data, it can always * short-circuit the request. However, this is the rare case. When * the proxy can't immediately respond, it attempts to short-circuit anyways, * delaying the reply until whatever it was waiting on arrives. Often * it can't -- if the most paranoid type of checking is turned on, it'll * never work. The complex part occurs with loose checking. If it knows * a reply is coming back, it can delay the short-circuit until it gets * the reply. This works fine for the core protocol, but breaks down * again for extensions -- to be safe, any unknown extensions are assumed * to have replies -- but since they may never arrive, the delayed * short-circuit can never be flushed. To avoid this, whether a reply * has been guessed at is tracked, and this info is used to decide * whether a short-circuit can be delayed -- if not, it always needs * to do the full round-trip. * * The complexity really makes me wonder if this stuff is worth the effort... */ /* short-circuiting protocol */ /* #define PROTOCOL_RAW /* pure Xremote */ /* #define PROTOCOL_SLOW /* no caching at all */ /* #define PROTOCOL_FULL /* best w/ accuracy */ /* #define PROTOCOL_MOST /* cheat on errors */ #define PROTOCOL_POOR /* cheat on errors & events */ #undef DEBUG #undef TRACE /* nostacking turns on code that assumes Xlib waits for replies before * issuing requests -- break XGetWindowAttributes(), perhaps others */ #undef nostacking /* possible states of request handlers. some requests are short-circuited * (yanked), some are replaced with LBX requests, and some are let through * unchanged * * any replaced request expecting a reply needs to be sure the sequence * number isn't lagging before its sends its data */ #define REQ_NOCHANGE 0 /* pass through untouched -- lbx sends data */ #define REQ_YANK 1 /* completely remove from stream */ #define REQ_REPLACE 2 /* replace with new encoding */ #define REQ_PASSTHROUGH 3 /* pass thorugh untouched, other sends data */ /* * how far we can let the server's sequence number slide before * bringing it up to date * * NOTE -- command only supports a char's worth of data */ #define MAX_SEQUENCE_LOST 255 /* * size of motion event queue * * this specifies the maximum number of motion events that the server * can spew out at once. the proxy will send it NUM_MOTION_EVENTS * AllowMotion requests at startup, and then send a new one each time it * processes a Motion event. this will prevent the wire from being * swamped by MotionNotify. */ /* XXX this should be a calculation based on the wire latency */ #define NUM_MOTION_EVENTS 8 typedef struct proptagdata { Atom type; int format; int length; /* in bytes */ pointer data; } PropertyTagDataRec, *PropertyTagDataPtr; typedef struct _querytag { XID tag; int tagtype; union { struct _modmap { int keyspermod; } modmap; struct _keymap { int keyspercode; int count; KeyCode first; } keymap; struct _getprop { CARD32 offset; CARD32 length; PropertyTagDataRec ptd; } getprop; struct _setup { int majorVersion; int minorVersion; pointer changes; } setup; } typedata; } QueryTagRec, *QueryTagPtr; typedef struct _replystuff { int sequenceNumber; /* expected sequence number */ int request; /* request code */ int extension; /* extension opcode */ Bool lbx_req; /* is this an LBX request? */ Bool guessed; /* did we have to guess? */ union { /* reply data */ struct atom_data { Atom atom; int len; char str[MAX_ATOM_LENGTH]; } lbxatom; struct colorname { char name[MAX_COLORNAME_LENGTH]; int namelen; Colormap cmap; } lbxlookupcolor; struct alloccolor { Colormap cmap; int red, green, blue; } lbxalloccolor; struct allocnamedcolor { char name[MAX_COLORNAME_LENGTH]; int namelen; Colormap cmap; } lbxallocnamedcolor; struct querytag { QueryTagRec info; } lbxquerytag; struct getkeymap { int count; int first; } lbxgetkeymap; struct getprop { CARD32 offset; CARD32 length; } lbxgetprop; struct changeprop { PropertyTagDataRec ptd; } lbxchangeprop; struct queryextension { char *name; } lbxqueryextension; struct getimage { #ifdef LBX_STATS Drawable drawable; INT16 x; INT16 y; #endif CARD16 width; CARD16 height; } lbxgetimage; pointer lbxextensiondata; } request_info; struct _replystuff *next; } ReplyStuffRec, *ReplyStuffPtr; typedef struct _replydata { int dlen; xReply reply; pointer data; int delay_seq_no; /* what seq i'm waiting for */ struct _replydata *next; } ReplyDataRec, *ReplyDataPtr; typedef struct _lbxdata { Bool cache_safe; /* safe to short circuit request? */ Bool can_delay_reply;/* safe to delay short-circuit request? */ int sequenceNumber; /* what we've seen */ int sequence_lost; /* requests short-circuited */ int lastReply; /* last sequence number seen from server */ int yanked; /* total requests short-circuited */ KeyCode minKeyCode, maxKeyCode; CARD8 imageByteOrder; /* LSBFirst, MSBFirst */ CARD8 bitmapBitOrder; /* LeastSignificant, MostSign...*/ CARD8 bitmapScanlineUnit, /* 8, 16, 32 */ bitmapScanlinePad; /* 8, 16, 32 */ ReplyStuffPtr replylist; /* list of pending replies */ ReplyDataPtr replydata; /* list of delayed short-circuited replies */ Drawable drawableCache[GFX_CACHE_SIZE]; GContext gcontextCache[GFX_CACHE_SIZE]; } LBXDataRec; typedef struct _lbxdata *LBXDataPtr; extern Bool MakeLBXStuff(); extern void FreeLBXStuff(); extern ReplyStuffPtr NewReply(); extern ReplyStuffPtr GetReply(); extern ReplyStuffPtr GetMatchingReply(); extern Bool FlushDelayedReply(); extern Bool SaveDelayedReply(); extern int NumReplies(); extern int NumGuessedReplies(); extern void RemoveReply(); extern void BumpSequence(); extern int QueryTag(); extern int GetQueryTagReply(); extern Bool DoLBXReply(); extern void FinishModmapReply(); extern void FinishKeymapReply(); extern void FinishQueryFontReply(); extern void FinishSetupReply(); extern void FinishGetPropertyReply(); extern Bool GetLbxGetPropertyReply(); extern void ForceSequenceUpdate(); extern void LbxFreeTag(); extern void LbxSendTagData(); #ifdef LBX_STATS extern int intern_good, intern_miss; extern int getatom_good, getatom_miss; extern int luc_good, luc_miss; extern int ac_good, ac_miss; extern int anc_good, anc_miss; extern int getmodmap_tag, /* tag only */ getmodmap_full; extern int getkeymap_tag, /* tag only */ getkeymap_full; extern int queryfont_tag, /* tag only */ queryfont_full; extern int getsetup_tag, /* tag only */ getsetup_full; extern int getprop_tag, getprop_full; extern int missed_tag; extern int tag_bytes_unsent; /* approx data kept off wire by tags */ extern void DumpStats(); extern void ZeroStats(); #endif #define LBXSequenceNumber(client) (((LBXDataPtr)((client)->screenPrivate[0]))->sequenceNumber) #define LBXCacheSafe(client) (((LBXDataPtr)((client)->screenPrivate[0]))->cache_safe) #define LBXCanDelayReply(client) (((LBXDataPtr)((client)->screenPrivate[0]))->can_delay_reply) #define LBXSequenceLost(client) (((LBXDataPtr)((client)->screenPrivate[0]))->sequence_lost) #define LBXYanked(client) (((LBXDataPtr)((client)->screenPrivate[0]))->yanked) #define LBXLastReply(client) (((LBXDataPtr)((client)->screenPrivate[0]))->lastReply) #define LBXReplyList(client) (((LBXDataPtr)((client)->screenPrivate[0]))->replylist) #define LBXReplyData(client) (((LBXDataPtr)((client)->screenPrivate[0]))->replydata) #define LBXMinKeyCode(client) (((LBXDataPtr)((client)->screenPrivate[0]))->minKeyCode) #define LBXMaxKeyCode(client) (((LBXDataPtr)((client)->screenPrivate[0]))->maxKeyCode) #define LBXImageByteOrder(client) (((LBXDataPtr)((client)->screenPrivate[0]))->imageByteOrder) #define LBXBitmapBitOrder(client) (((LBXDataPtr)((client)->screenPrivate[0]))->bitmapBitOrder) #define LBXBitmapScanlineUnit(client) (((LBXDataPtr)((client)->screenPrivate[0]))->bitmapScanlineUnit) #define LBXBitmapScanlinePad(client) (((LBXDataPtr)((client)->screenPrivate[0]))->bitmapScanlinePad) #define LBXDrawableCache(client)(((LBXDataPtr)((client)->screenPrivate[0]))->drawableCache) #define LBXGContextCache(client)(((LBXDataPtr)((client)->screenPrivate[0]))->gcontextCache) #endif /* _LBXDATA_H_ */