From: Frank Mori Hess <fmhess@speakeasy.net>
Date: Thu, 8 Feb 2001 02:00:36 +0000 (+0000)
Subject: made bufconfig ioctl always write back buffer sizes even if they were not changed
X-Git-Tag: r0_7_57~31
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=db8d1fb0973971c091c33786771b13ee53bb986b;p=comedi.git

made bufconfig ioctl always write back buffer sizes even if they were not changed
---

diff --git a/comedi/comedi_fops.c b/comedi/comedi_fops.c
index f7ca89f8..082d3ba7 100644
--- a/comedi/comedi_fops.c
+++ b/comedi/comedi_fops.c
@@ -171,15 +171,18 @@ static int do_bufconfig_ioctl(comedi_device *dev,void *arg)
 	if(copy_from_user(&bc,arg,sizeof(comedi_bufconfig)))
 		return -EFAULT;
 
+	if(dev->read_subdev >= 0)
+		rsd = &dev->subdevices[dev->read_subdev];
+	if(dev->write_subdev >= 0)
+		wsd = &dev->subdevices[dev->write_subdev];
+
 	if(bc.read_size){
-		if(dev->read_subdev < 0)
+		if(rsd == NULL)
 		{
 			DPRINTK("device has no read subdevice, buffer resize failed\n");
 			return -ENODEV;
 		}
 
-		rsd = &dev->subdevices[dev->read_subdev];
-
 		if(rsd->busy)
 			return -EBUSY;
 
@@ -192,14 +195,12 @@ static int do_bufconfig_ioctl(comedi_device *dev,void *arg)
 			return -EINVAL;
 	}
 	if(bc.write_size){
-		if(dev->write_subdev < 0)
+		if(wsd == NULL)
 		{
 			DPRINTK("device has no write subdevice, buffer resize failed\n");
 			return -ENODEV;
 		}
 
-		wsd = &dev->subdevices[dev->write_subdev];
-
 		if(wsd->busy)
 			return -EBUSY;
 
@@ -219,8 +220,7 @@ static int do_bufconfig_ioctl(comedi_device *dev,void *arg)
 		if(ret < 0)
 			return ret;
 
-		bc.read_size = rsd->prealloc_bufsz;
-		DPRINTK("comedi%i read buffer resized to %i bytes\n", dev->minor, bc.read_size);
+		DPRINTK("comedi%i read buffer resized to %i bytes\n", dev->minor, rsd->prealloc_bufsz);
 	}
 	if(bc.write_size){
 		ret = resize_buf(dev,wsd,bc.write_size);
@@ -228,10 +228,17 @@ static int do_bufconfig_ioctl(comedi_device *dev,void *arg)
 		if(ret < 0)
 			return ret;
 
-		bc.write_size = wsd->prealloc_bufsz;
-		DPRINTK("comedi%i write buffer resized to %i bytes\n", dev->minor, bc.write_size);
+		DPRINTK("comedi%i write buffer resized to %i bytes\n", dev->minor, wsd->prealloc_bufsz);
 	}
 
+	// write back buffer sizes
+	if(rsd){
+		bc.read_size = rsd->prealloc_bufsz;
+	} else bc.read_size = 0;
+	if(wsd){
+		bc.write_size = wsd->prealloc_bufsz;
+	} else bc.write_size = 0;
+
 	if(copy_to_user(arg,&bc,sizeof(comedi_bufconfig)))
 		return -EFAULT;