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 <info@metux.net>
This commit is contained in:
Enrico Weigelt, metux IT consult
2024-07-29 15:03:35 +02:00
parent da336d0fe3
commit cc6a76545b
3 changed files with 70 additions and 69 deletions

View File

@@ -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);
}

View File

@@ -141,4 +141,6 @@ int ProcRRSelectInput(ClientPtr client);
int ProcRRDispatch(ClientPtr client);
int SProcRRDispatch(ClientPtr client);
#endif /* _XSERVER_RANDRSTR_PRIV_H_ */

View File

@@ -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;
}