Add checkonly handling to property handlers.

If checkonly is TRUE, we can only check if applying the value would succeed.
The value is actually applied if checkonly is FALSE.

5 files changed, 70 insertions, 44 deletions

diff --git a/src/draglock.c b/src/draglock.c
index 90809c9..86142b6 100644
--- a/src/draglock.c
+++ b/src/draglock.c
@@ -257,7 +257,8 @@ EvdevDragLockInitProperty(DeviceIntPtr dev)
  * i.e. to set bt 3 to draglock button 1, supply 0,0,1
  */
 int
-EvdevDragLockSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
+EvdevDragLockSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val,
+                         BOOL checkonly)
 {
     InputInfoPtr pInfo  = dev->public.devicePrivate;
     EvdevPtr     pEvdev = pInfo->private;
@@ -287,8 +288,11 @@ EvdevDragLockSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
             if (meta > EVDEV_MAXBUTTONS)
                 return BadValue;
 
-            pEvdev->dragLock.meta = meta;
-            memset(pEvdev->dragLock.lock_pair, 0, sizeof(pEvdev->dragLock.lock_pair));
+            if (!checkonly)
+            {
+                pEvdev->dragLock.meta = meta;
+                memset(pEvdev->dragLock.lock_pair, 0, sizeof(pEvdev->dragLock.lock_pair));
+            }
         } else
         {
             CARD8* vals = (CARD8*)val->data;
@@ -297,11 +301,14 @@ EvdevDragLockSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
                 if (vals[i] > EVDEV_MAXBUTTONS)
                     return BadValue;
 
-            pEvdev->dragLock.meta = 0;
-            memset(pEvdev->dragLock.lock_pair, 0, sizeof(pEvdev->dragLock.lock_pair));
+            if (!checkonly)
+            {
+                pEvdev->dragLock.meta = 0;
+                memset(pEvdev->dragLock.lock_pair, 0, sizeof(pEvdev->dragLock.lock_pair));
 
-            for (i = 0; i < val->size && i < EVDEV_MAXBUTTONS; i++)
-                pEvdev->dragLock.lock_pair[i] = vals[i];
+                for (i = 0; i < val->size && i < EVDEV_MAXBUTTONS; i++)
+                    pEvdev->dragLock.lock_pair[i] = vals[i];
+            }
         }
     }
 
diff --git a/src/emuMB.c b/src/emuMB.c
index 5de5227..472e74f 100644
--- a/src/emuMB.c
+++ b/src/emuMB.c
@@ -385,7 +385,8 @@ EvdevMBEmuInitProperty(DeviceIntPtr dev)
 }
 
 int
-EvdevMBEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
+EvdevMBEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val,
+                      BOOL checkonly)
 {
     InputInfoPtr pInfo  = dev->public.devicePrivate;
     EvdevPtr     pEvdev = pInfo->private;
@@ -395,13 +396,15 @@ EvdevMBEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
         if (val->format != 8 || val->size != 1 || val->type != XA_INTEGER)
             return BadMatch;
 
-        pEvdev->emulateMB.enabled = *((BOOL*)val->data);
+        if (!checkonly)
+            pEvdev->emulateMB.enabled = *((BOOL*)val->data);
     } else if (atom == prop_mbtimeout)
     {
         if (val->format != 16 || val->size != 1 || val->type != XA_INTEGER)
             return BadMatch;
 
-        pEvdev->emulateMB.timeout = *((INT16*)val->data);
+        if (!checkonly)
+            pEvdev->emulateMB.timeout = *((INT16*)val->data);
     }
 
     return Success;
diff --git a/src/emuWheel.c b/src/emuWheel.c
index 27dec7c..246ab47 100644
--- a/src/emuWheel.c
+++ b/src/emuWheel.c
@@ -394,7 +394,8 @@ EvdevWheelEmuInitProperty(DeviceIntPtr dev)
 
 
 int
-EvdevWheelEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
+EvdevWheelEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val,
+                         BOOL checkonly)
 {
     InputInfoPtr pInfo  = dev->public.devicePrivate;
     EvdevPtr     pEvdev = pInfo->private;
@@ -404,26 +405,29 @@ EvdevWheelEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
         if (val->format != 8 || val->size != 1 || val->type != XA_INTEGER)
             return BadMatch;
 
-        pEvdev->emulateWheel.enabled = *((BOOL*)val->data);
-        /* Don't enable with zero inertia, otherwise we may get stuck in an
-         * infinite loop */
-        if (pEvdev->emulateWheel.inertia <= 0)
+        if (!checkonly)
         {
-            pEvdev->emulateWheel.inertia = 10;
-            /* We may get here before the property is actually enabled */
-            if (prop_wheel_inertia)
-                XIChangeDeviceProperty(dev, prop_wheel_inertia, XA_INTEGER,
-                                       16, PropModeReplace, 1,
-                                       &pEvdev->emulateWheel.inertia, TRUE);
-        }
+            pEvdev->emulateWheel.enabled = *((BOOL*)val->data);
+            /* Don't enable with zero inertia, otherwise we may get stuck in an
+             * infinite loop */
+            if (pEvdev->emulateWheel.inertia <= 0)
+            {
+                pEvdev->emulateWheel.inertia = 10;
+                /* We may get here before the property is actually enabled */
+                if (prop_wheel_inertia)
+                    XIChangeDeviceProperty(dev, prop_wheel_inertia, XA_INTEGER,
+                            16, PropModeReplace, 1,
+                            &pEvdev->emulateWheel.inertia, TRUE);
+            }
 
-        /* Don't enable with negative timeout */
-        if (pEvdev->emulateWheel.timeout < 0)
-        {
-            pEvdev->emulateWheel.timeout = 200;
-            XIChangeDeviceProperty(dev, prop_wheel_timeout, XA_INTEGER, 16,
-                                   PropModeReplace, 1,
-                                   &pEvdev->emulateWheel.timeout, TRUE);
+            /* Don't enable with negative timeout */
+            if (pEvdev->emulateWheel.timeout < 0)
+            {
+                pEvdev->emulateWheel.timeout = 200;
+                XIChangeDeviceProperty(dev, prop_wheel_timeout, XA_INTEGER, 16,
+                        PropModeReplace, 1,
+                        &pEvdev->emulateWheel.timeout, TRUE);
+            }
         }
     }
     else if (atom == prop_wheel_button)
@@ -435,16 +439,21 @@ EvdevWheelEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
 
         if (bt < 0 || bt >= EVDEV_MAXBUTTONS)
             return BadValue;
-        pEvdev->emulateWheel.button = bt;
+
+        if (!checkonly)
+            pEvdev->emulateWheel.button = bt;
     } else if (atom == prop_wheel_axismap)
     {
         if (val->format != 8 || val->size != 4 || val->type != XA_INTEGER)
             return BadMatch;
 
-        pEvdev->emulateWheel.X.up_button = *((CARD8*)val->data);
-        pEvdev->emulateWheel.X.down_button = *(((CARD8*)val->data) + 1);
-        pEvdev->emulateWheel.Y.up_button = *(((CARD8*)val->data) + 2);
-        pEvdev->emulateWheel.Y.down_button = *(((CARD8*)val->data) + 3);
+        if (!checkonly)
+        {
+            pEvdev->emulateWheel.X.up_button = *((CARD8*)val->data);
+            pEvdev->emulateWheel.X.down_button = *(((CARD8*)val->data) + 1);
+            pEvdev->emulateWheel.Y.up_button = *(((CARD8*)val->data) + 2);
+            pEvdev->emulateWheel.Y.down_button = *(((CARD8*)val->data) + 3);
+        }
     } else if (atom == prop_wheel_inertia)
     {
         int inertia = *((CARD16*)val->data);
@@ -455,7 +464,8 @@ EvdevWheelEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
         if (inertia < 0)
             return BadValue;
 
-        pEvdev->emulateWheel.inertia = inertia;
+        if (!checkonly)
+            pEvdev->emulateWheel.inertia = inertia;
     } else if (atom == prop_wheel_timeout)
     {
         int timeout = *((CARD16*)val->data);
@@ -466,7 +476,8 @@ EvdevWheelEmuSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
         if (timeout < 0)
             return BadValue;
 
-        pEvdev->emulateWheel.timeout = timeout;
+        if (!checkonly)
+            pEvdev->emulateWheel.timeout = timeout;
     }
     return Success;
 }
diff --git a/src/evdev.c b/src/evdev.c
index 1c2a559..97cc41c 100644
--- a/src/evdev.c
+++ b/src/evdev.c
@@ -108,7 +108,7 @@ static int EvdevCacheCompare(InputInfoPtr pInfo, Bool compare);
 #ifdef HAVE_PROPERTIES
 static void EvdevInitProperty(DeviceIntPtr dev);
 static int EvdevSetProperty(DeviceIntPtr dev, Atom atom,
-                            XIPropertyValuePtr val);
+                            XIPropertyValuePtr val, BOOL checkonly);
 static Atom prop_invert = 0;
 
 #endif
@@ -1494,7 +1494,8 @@ EvdevInitProperty(DeviceIntPtr dev)
 }
 
 static int
-EvdevSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
+EvdevSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val,
+                 BOOL checkonly)
 {
     InputInfoPtr pInfo  = dev->public.devicePrivate;
     EvdevPtr     pEvdev = pInfo->private;
@@ -1504,9 +1505,13 @@ EvdevSetProperty(DeviceIntPtr dev, Atom atom, XIPropertyValuePtr val)
         BOOL* data;
         if (val->format != 8 || val->size != 2 || val->type != XA_INTEGER)
             return BadMatch;
-        data = (BOOL*)val->data;
-        pEvdev->invert_x = data[0];
-        pEvdev->invert_y = data[1];
+
+        if (!checkonly)
+        {
+            data = (BOOL*)val->data;
+            pEvdev->invert_x = data[0];
+            pEvdev->invert_y = data[1];
+        }
     }
 
     return Success;
diff --git a/src/evdev.h b/src/evdev.h
index 525acb1..aa74481 100644
--- a/src/evdev.h
+++ b/src/evdev.h
@@ -133,13 +133,13 @@ unsigned int EvdevUtilButtonEventToButtonNumber(int code);
 
 #ifdef HAVE_PROPERTIES
 void EvdevMBEmuInitProperty(DeviceIntPtr);
-int EvdevMBEmuSetProperty(DeviceIntPtr, Atom, XIPropertyValuePtr);
+int EvdevMBEmuSetProperty(DeviceIntPtr, Atom, XIPropertyValuePtr, BOOL);
 
 void EvdevWheelEmuInitProperty(DeviceIntPtr);
-int EvdevWheelEmuSetProperty(DeviceIntPtr, Atom, XIPropertyValuePtr);
+int EvdevWheelEmuSetProperty(DeviceIntPtr, Atom, XIPropertyValuePtr, BOOL);
 
 void EvdevDragLockInitProperty(DeviceIntPtr);
-int EvdevDragLockSetProperty(DeviceIntPtr, Atom, XIPropertyValuePtr);
+int EvdevDragLockSetProperty(DeviceIntPtr, Atom, XIPropertyValuePtr, BOOL);
 #endif
 
 /* Mouse Wheel emulation */