From cc6a76545b463bba2ddad3448d26531e24573da9 Mon Sep 17 00:00:00 2001 From: "Enrico Weigelt, metux IT consult" Date: Mon, 29 Jul 2024 15:03:35 +0200 Subject: [PATCH] randr: use explicit case statement instead of SProcRandrVector table No need to go indirectly through a vector table, since everything's fixed anyways. It's not a pretty robust programming style: any changes need great care, in order to not mix up things. Replacing this by direct switch/case statement, which is using the defines from the xrandr protocol headers. Also adding a little bit more protection against subtle programming errors and reducing cognitive load (source size) on understanding the code by using a tiny macro for deducing define name and function name from the request's name. This approach actually uncovered some subtle bug that had been waiting in the dark for over 15 years. As collateral benefit, getting a tiny bit better performance. Signed-off-by: Enrico Weigelt, metux IT consult --- randr/randr.c | 12 ---- randr/randrstr_priv.h | 2 + randr/rrsdispatch.c | 125 +++++++++++++++++++++++------------------- 3 files changed, 70 insertions(+), 69 deletions(-) diff --git a/randr/randr.c b/randr/randr.c index f367d1f168..67132b3c34 100644 --- a/randr/randr.c +++ b/randr/randr.c @@ -50,8 +50,6 @@ static int RRNScreens; real->mem = priv->mem; \ } -static int SProcRRDispatch(ClientPtr pClient); - int RREventBase; int RRErrorBase; RESTYPE RRClientType, RREventType; /* resource types for event masks */ @@ -721,13 +719,3 @@ RRVerticalRefresh(xRRModeInfo * mode) refresh = 0xffff; return (CARD16) refresh; } - -static int _X_COLD -SProcRRDispatch(ClientPtr client) -{ - REQUEST(xReq); - if (stuff->data >= RRNumberRequests || !SProcRandrVector[stuff->data]) - return BadRequest; - UpdateCurrentTimeIf(); - return (*SProcRandrVector[stuff->data]) (client); -} diff --git a/randr/randrstr_priv.h b/randr/randrstr_priv.h index a125f293ab..7037e81db3 100644 --- a/randr/randrstr_priv.h +++ b/randr/randrstr_priv.h @@ -141,4 +141,6 @@ int ProcRRSelectInput(ClientPtr client); int ProcRRDispatch(ClientPtr client); +int SProcRRDispatch(ClientPtr client); + #endif /* _XSERVER_RANDRSTR_PRIV_H_ */ diff --git a/randr/rrsdispatch.c b/randr/rrsdispatch.c index 70cbd4a684..c7f3ec165d 100644 --- a/randr/rrsdispatch.c +++ b/randr/rrsdispatch.c @@ -647,60 +647,71 @@ SProcRRFreeLease(ClientPtr client) { return ProcRRFreeLease(client); } -int (*SProcRandrVector[RRNumberRequests]) (ClientPtr) = { - SProcRRQueryVersion, /* 0 */ -/* we skip 1 to make old clients fail pretty immediately */ - NULL, /* 1 SProcRandrOldGetScreenInfo */ -/* V1.0 apps share the same set screen config request id */ - SProcRRSetScreenConfig, /* 2 */ - NULL, /* 3 SProcRandrOldScreenChangeSelectInput */ -/* 3 used to be ScreenChangeSelectInput; deprecated */ - SProcRRSelectInput, /* 4 */ - SProcRRGetScreenInfo, /* 5 */ -/* V1.2 additions */ - SProcRRGetScreenSizeRange, /* 6 */ - SProcRRSetScreenSize, /* 7 */ - SProcRRGetScreenResources, /* 8 */ - SProcRRGetOutputInfo, /* 9 */ - SProcRRListOutputProperties, /* 10 */ - SProcRRQueryOutputProperty, /* 11 */ - SProcRRConfigureOutputProperty, /* 12 */ - SProcRRChangeOutputProperty, /* 13 */ - SProcRRDeleteOutputProperty, /* 14 */ - SProcRRGetOutputProperty, /* 15 */ - SProcRRCreateMode, /* 16 */ - SProcRRDestroyMode, /* 17 */ - SProcRRAddOutputMode, /* 18 */ - SProcRRDeleteOutputMode, /* 19 */ - SProcRRGetCrtcInfo, /* 20 */ - SProcRRSetCrtcConfig, /* 21 */ - SProcRRGetCrtcGammaSize, /* 22 */ - SProcRRGetCrtcGamma, /* 23 */ - SProcRRSetCrtcGamma, /* 24 */ -/* V1.3 additions */ - SProcRRGetScreenResourcesCurrent, /* 25 */ - SProcRRSetCrtcTransform, /* 26 */ - SProcRRGetCrtcTransform, /* 27 */ - SProcRRGetPanning, /* 28 */ - SProcRRSetPanning, /* 29 */ - SProcRRSetOutputPrimary, /* 30 */ - SProcRRGetOutputPrimary, /* 31 */ -/* V1.4 additions */ - SProcRRGetProviders, /* 32 */ - SProcRRGetProviderInfo, /* 33 */ - SProcRRSetProviderOffloadSink, /* 34 */ - SProcRRSetProviderOutputSource, /* 35 */ - SProcRRListProviderProperties, /* 36 */ - SProcRRQueryProviderProperty, /* 37 */ - SProcRRConfigureProviderProperty, /* 38 */ - SProcRRChangeProviderProperty, /* 39 */ - SProcRRDeleteProviderProperty, /* 40 */ - SProcRRGetProviderProperty, /* 41 */ -/* V1.5 additions */ - SProcRRGetMonitors, /* 42 */ - SProcRRSetMonitor, /* 43 */ - SProcRRDeleteMonitor, /* 44 */ -/* V1.6 additions */ - SProcRRCreateLease, /* 45 */ - SProcRRFreeLease, /* 46 */ -}; +#define HANDLER(name) case X_##name: return SProc##name(client) + +int +SProcRRDispatch(ClientPtr client) +{ + REQUEST(xReq); + UpdateCurrentTimeIf(); + + switch (stuff->data) { + HANDLER(RRQueryVersion); + HANDLER(RRSetScreenConfig); + HANDLER(RRSelectInput); + HANDLER(RRGetScreenInfo); + + /* V1.2 additions */ + HANDLER(RRGetScreenSizeRange); + HANDLER(RRSetScreenSize); + HANDLER(RRGetScreenResources); + HANDLER(RRGetOutputInfo); + HANDLER(RRListOutputProperties); + HANDLER(RRQueryOutputProperty); + HANDLER(RRConfigureOutputProperty); + HANDLER(RRChangeOutputProperty); + HANDLER(RRDeleteOutputProperty); + HANDLER(RRGetOutputProperty); + HANDLER(RRCreateMode); + HANDLER(RRDestroyMode); + HANDLER(RRAddOutputMode); + HANDLER(RRDeleteOutputMode); + HANDLER(RRGetCrtcInfo); + HANDLER(RRSetCrtcConfig); + HANDLER(RRGetCrtcGammaSize); + HANDLER(RRGetCrtcGamma); + HANDLER(RRSetCrtcGamma); + + /* V1.3 additions */ + HANDLER(RRGetScreenResourcesCurrent); + HANDLER(RRSetCrtcTransform); + HANDLER(RRGetCrtcTransform); + HANDLER(RRGetPanning); + HANDLER(RRSetPanning); + HANDLER(RRSetOutputPrimary); + HANDLER(RRGetOutputPrimary); + + /* V1.4 additions */ + HANDLER(RRGetProviders); + HANDLER(RRGetProviderInfo); + HANDLER(RRSetProviderOffloadSink); + HANDLER(RRSetProviderOutputSource); + HANDLER(RRListProviderProperties); + HANDLER(RRQueryProviderProperty); + HANDLER(RRConfigureProviderProperty); + HANDLER(RRChangeProviderProperty); + HANDLER(RRDeleteProviderProperty); + HANDLER(RRGetProviderProperty); + + /* V1.5 additions */ + HANDLER(RRGetMonitors); + HANDLER(RRSetMonitor); + HANDLER(RRDeleteMonitor); + + /* V1.6 additions */ + HANDLER(RRCreateLease); + HANDLER(RRFreeLease); + } + + return BadRequest; +}