This is one more interface fix for the video-buf.c module, the first
attempt on that wasn't that clever. Instead of passing the driver
private data through all function calls I've just made that an element
of the videobuf_queue struct which is passed around everythere _anyway_.
That removes some reduncancy, should be less error prone and gain me
some points on rusty's interface design scala ;)
Ah, it also fixes the tvtime crashes which where caused by overviewing
one place to fixup in the first attempt.
Signed-off-by: Gerd Knorr <[email protected]>
---
drivers/media/video/video-buf.c | 133 ++++++++++++++++----------------
include/media/video-buf.h | 53 +++++++-----
2 files changed, 97 insertions(+), 89 deletions(-)
Index: linux-2004-11-05/include/media/video-buf.h
===================================================================
--- linux-2004-11-05.orig/include/media/video-buf.h 2004-11-07 12:22:57.000000000 +0100
+++ linux-2004-11-05/include/media/video-buf.h 2004-11-07 15:38:58.617839558 +0100
@@ -1,5 +1,5 @@
/*
- * $Id: video-buf.h,v 1.8 2004/10/13 10:39:00 kraxel Exp $
+ * $Id: video-buf.h,v 1.9 2004/11/07 13:17:15 kraxel Exp $
*
* generic helper functions for video4linux capture buffers, to handle
* memory management and PCI DMA. Right now bttv + saa7134 use it.
@@ -121,7 +121,6 @@ struct videobuf_queue;
struct videobuf_mapping {
unsigned int count;
- int highmem_ok;
unsigned long start;
unsigned long end;
struct videobuf_queue *q;
@@ -167,12 +166,15 @@ struct videobuf_buffer {
};
struct videobuf_queue_ops {
- int (*buf_setup)(void *priv,
+ int (*buf_setup)(struct videobuf_queue *q,
unsigned int *count, unsigned int *size);
- int (*buf_prepare)(void *priv,struct videobuf_buffer *vb,
+ int (*buf_prepare)(struct videobuf_queue *q,
+ struct videobuf_buffer *vb,
enum v4l2_field field);
- void (*buf_queue)(void *priv,struct videobuf_buffer *vb);
- void (*buf_release)(void *priv,struct videobuf_buffer *vb);
+ void (*buf_queue)(struct videobuf_queue *q,
+ struct videobuf_buffer *vb);
+ void (*buf_release)(struct videobuf_queue *q,
+ struct videobuf_buffer *vb);
};
struct videobuf_queue {
@@ -196,6 +198,9 @@ struct videobuf_queue {
unsigned int reading;
unsigned int read_off;
struct videobuf_buffer *read_buf;
+
+ /* driver private data */
+ void *priv_data;
};
void* videobuf_alloc(unsigned int size);
@@ -205,44 +210,46 @@ int videobuf_iolock(struct pci_dev *pci,
void videobuf_queue_init(struct videobuf_queue *q,
struct videobuf_queue_ops *ops,
- struct pci_dev *pci, spinlock_t *irqlock,
+ struct pci_dev *pci,
+ spinlock_t *irqlock,
enum v4l2_buf_type type,
enum v4l2_field field,
- unsigned int msize);
+ unsigned int msize,
+ void *priv);
int videobuf_queue_is_busy(struct videobuf_queue *q);
-void videobuf_queue_cancel(void *priv, struct videobuf_queue *q);
+void videobuf_queue_cancel(struct videobuf_queue *q);
enum v4l2_field videobuf_next_field(struct videobuf_queue *q);
void videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
enum v4l2_buf_type type);
-int videobuf_reqbufs(void *priv, struct videobuf_queue *q,
+int videobuf_reqbufs(struct videobuf_queue *q,
struct v4l2_requestbuffers *req);
int videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b);
-int videobuf_qbuf(void *priv, struct videobuf_queue *q,
+int videobuf_qbuf(struct videobuf_queue *q,
struct v4l2_buffer *b);
-int videobuf_dqbuf(void *priv, struct videobuf_queue *q,
+int videobuf_dqbuf(struct videobuf_queue *q,
struct v4l2_buffer *b, int nonblocking);
-int videobuf_streamon(void *priv, struct videobuf_queue *q);
-int videobuf_streamoff(void *priv, struct videobuf_queue *q);
+int videobuf_streamon(struct videobuf_queue *q);
+int videobuf_streamoff(struct videobuf_queue *q);
-int videobuf_read_start(void *priv, struct videobuf_queue *q);
-void videobuf_read_stop(void *priv, struct videobuf_queue *q);
-ssize_t videobuf_read_stream(void *priv, struct videobuf_queue *q,
+int videobuf_read_start(struct videobuf_queue *q);
+void videobuf_read_stop(struct videobuf_queue *q);
+ssize_t videobuf_read_stream(struct videobuf_queue *q,
char __user *data, size_t count, loff_t *ppos,
int vbihack, int nonblocking);
-ssize_t videobuf_read_one(void *priv, struct videobuf_queue *q,
+ssize_t videobuf_read_one(struct videobuf_queue *q,
char __user *data, size_t count, loff_t *ppos,
int nonblocking);
-unsigned int videobuf_poll_stream(struct file *file, void *priv,
+unsigned int videobuf_poll_stream(struct file *file,
struct videobuf_queue *q,
poll_table *wait);
-int videobuf_mmap_setup(void *priv, struct videobuf_queue *q,
+int videobuf_mmap_setup(struct videobuf_queue *q,
unsigned int bcount, unsigned int bsize,
enum v4l2_memory memory);
-int videobuf_mmap_free(void *priv, struct videobuf_queue *q);
-int videobuf_mmap_mapper(struct vm_area_struct *vma,
- struct videobuf_queue *q);
+int videobuf_mmap_free(struct videobuf_queue *q);
+int videobuf_mmap_mapper(struct videobuf_queue *q,
+ struct vm_area_struct *vma);
/* --------------------------------------------------------------------- */
Index: linux-2004-11-05/drivers/media/video/video-buf.c
===================================================================
--- linux-2004-11-05.orig/drivers/media/video/video-buf.c 2004-11-07 12:22:48.000000000 +0100
+++ linux-2004-11-05/drivers/media/video/video-buf.c 2004-11-07 15:48:15.881027141 +0100
@@ -1,5 +1,5 @@
/*
- * $Id: video-buf.c,v 1.13 2004/10/13 10:39:00 kraxel Exp $
+ * $Id: video-buf.c,v 1.15 2004/11/07 14:45:00 kraxel Exp $
*
* generic helper functions for video4linux capture buffers, to handle
* memory management and PCI DMA. Right now bttv + saa7134 use it.
@@ -36,11 +36,11 @@
{ printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
static int debug = 0;
+module_param(debug, int, 0644);
MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
MODULE_AUTHOR("Gerd Knorr <[email protected]> [SuSE Labs]");
MODULE_LICENSE("GPL");
-MODULE_PARM(debug,"i");
#define dprintk(level, fmt, arg...) if (debug >= level) \
printk(KERN_DEBUG "vbuf: " fmt , ## arg)
@@ -361,23 +361,23 @@ videobuf_iolock(struct pci_dev *pci, str
/* --------------------------------------------------------------------- */
-void
-videobuf_queue_init(struct videobuf_queue *q,
- struct videobuf_queue_ops *ops,
- struct pci_dev *pci,
- spinlock_t *irqlock,
- enum v4l2_buf_type type,
- enum v4l2_field field,
- unsigned int msize)
+void videobuf_queue_init(struct videobuf_queue* q,
+ struct videobuf_queue_ops *ops,
+ struct pci_dev *pci,
+ spinlock_t *irqlock,
+ enum v4l2_buf_type type,
+ enum v4l2_field field,
+ unsigned int msize,
+ void *priv)
{
memset(q,0,sizeof(*q));
-
q->irqlock = irqlock;
q->pci = pci;
q->type = type;
q->field = field;
q->msize = msize;
q->ops = ops;
+ q->priv_data = priv;
init_MUTEX(&q->lock);
INIT_LIST_HEAD(&q->stream);
@@ -420,7 +420,7 @@ videobuf_queue_is_busy(struct videobuf_q
}
void
-videobuf_queue_cancel(void *priv, struct videobuf_queue *q)
+videobuf_queue_cancel(struct videobuf_queue *q)
{
unsigned long flags;
int i;
@@ -441,7 +441,7 @@ videobuf_queue_cancel(void *priv, struct
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
- q->ops->buf_release(priv,q->bufs[i]);
+ q->ops->buf_release(q,q->bufs[i]);
}
INIT_LIST_HEAD(&q->stream);
}
@@ -523,7 +523,7 @@ videobuf_status(struct v4l2_buffer *b, s
}
int
-videobuf_reqbufs(void *priv, struct videobuf_queue *q,
+videobuf_reqbufs(struct videobuf_queue *q,
struct v4l2_requestbuffers *req)
{
unsigned int size,count;
@@ -548,12 +548,12 @@ videobuf_reqbufs(void *priv, struct vide
if (count > VIDEO_MAX_FRAME)
count = VIDEO_MAX_FRAME;
size = 0;
- q->ops->buf_setup(priv,&count,&size);
+ q->ops->buf_setup(q,&count,&size);
size = PAGE_ALIGN(size);
dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
count, size, (count*size)>>PAGE_SHIFT);
- retval = videobuf_mmap_setup(priv,q,count,size,req->memory);
+ retval = videobuf_mmap_setup(q,count,size,req->memory);
if (retval < 0)
goto done;
@@ -578,7 +578,7 @@ videobuf_querybuf(struct videobuf_queue
}
int
-videobuf_qbuf(void *priv, struct videobuf_queue *q,
+videobuf_qbuf(struct videobuf_queue *q,
struct v4l2_buffer *b)
{
struct videobuf_buffer *buf;
@@ -622,7 +622,7 @@ videobuf_qbuf(void *priv, struct videobu
if (b->length < buf->bsize)
goto done;
if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
- q->ops->buf_release(priv,buf);
+ q->ops->buf_release(q,buf);
buf->baddr = b->m.userptr;
break;
case V4L2_MEMORY_OVERLAY:
@@ -633,14 +633,14 @@ videobuf_qbuf(void *priv, struct videobu
}
field = videobuf_next_field(q);
- retval = q->ops->buf_prepare(priv,buf,field);
+ retval = q->ops->buf_prepare(q,buf,field);
if (0 != retval)
goto done;
list_add_tail(&buf->stream,&q->stream);
if (q->streaming) {
spin_lock_irqsave(q->irqlock,flags);
- q->ops->buf_queue(priv,buf);
+ q->ops->buf_queue(q,buf);
spin_unlock_irqrestore(q->irqlock,flags);
}
retval = 0;
@@ -651,7 +651,7 @@ videobuf_qbuf(void *priv, struct videobu
}
int
-videobuf_dqbuf(void *priv, struct videobuf_queue *q,
+videobuf_dqbuf(struct videobuf_queue *q,
struct v4l2_buffer *b, int nonblocking)
{
struct videobuf_buffer *buf;
@@ -691,7 +691,7 @@ videobuf_dqbuf(void *priv, struct videob
return retval;
}
-int videobuf_streamon(void *priv, struct videobuf_queue *q)
+int videobuf_streamon(struct videobuf_queue *q)
{
struct videobuf_buffer *buf;
struct list_head *list;
@@ -710,7 +710,7 @@ int videobuf_streamon(void *priv, struct
list_for_each(list,&q->stream) {
buf = list_entry(list, struct videobuf_buffer, stream);
if (buf->state == STATE_PREPARED)
- q->ops->buf_queue(priv,buf);
+ q->ops->buf_queue(q,buf);
}
spin_unlock_irqrestore(q->irqlock,flags);
@@ -719,14 +719,14 @@ int videobuf_streamon(void *priv, struct
return retval;
}
-int videobuf_streamoff(void *priv, struct videobuf_queue *q)
+int videobuf_streamoff(struct videobuf_queue *q)
{
int retval = -EINVAL;
down(&q->lock);
if (!q->streaming)
goto done;
- videobuf_queue_cancel(priv,q);
+ videobuf_queue_cancel(q);
q->streaming = 0;
retval = 0;
@@ -736,8 +736,8 @@ int videobuf_streamoff(void *priv, struc
}
static ssize_t
-videobuf_read_zerocopy(void *priv, struct videobuf_queue *q,
- char __user *data, size_t count, loff_t *ppos)
+videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
+ size_t count, loff_t *ppos)
{
enum v4l2_field field;
unsigned long flags;
@@ -753,13 +753,13 @@ videobuf_read_zerocopy(void *priv, struc
q->read_buf->baddr = (unsigned long)data;
q->read_buf->bsize = count;
field = videobuf_next_field(q);
- retval = q->ops->buf_prepare(priv,q->read_buf,field);
+ retval = q->ops->buf_prepare(q,q->read_buf,field);
if (0 != retval)
goto done;
/* start capture & wait */
spin_lock_irqsave(q->irqlock,flags);
- q->ops->buf_queue(priv,q->read_buf);
+ q->ops->buf_queue(q,q->read_buf);
spin_unlock_irqrestore(q->irqlock,flags);
retval = videobuf_waiton(q->read_buf,0,0);
if (0 == retval) {
@@ -772,13 +772,13 @@ videobuf_read_zerocopy(void *priv, struc
done:
/* cleanup */
- q->ops->buf_release(priv,q->read_buf);
+ q->ops->buf_release(q,q->read_buf);
kfree(q->read_buf);
q->read_buf = NULL;
return retval;
}
-ssize_t videobuf_read_one(void *priv, struct videobuf_queue *q,
+ssize_t videobuf_read_one(struct videobuf_queue *q,
char __user *data, size_t count, loff_t *ppos,
int nonblocking)
{
@@ -790,11 +790,11 @@ ssize_t videobuf_read_one(void *priv, st
down(&q->lock);
nbufs = 1; size = 0;
- q->ops->buf_setup(priv,&nbufs,&size);
+ q->ops->buf_setup(q,&nbufs,&size);
if (NULL == q->read_buf &&
count >= size &&
!nonblocking) {
- retval = videobuf_read_zerocopy(priv,q,data,count,ppos);
+ retval = videobuf_read_zerocopy(q,data,count,ppos);
if (retval >= 0 || retval == -EIO)
/* ok, all done */
goto done;
@@ -809,11 +809,11 @@ ssize_t videobuf_read_one(void *priv, st
goto done;
q->read_buf->memory = V4L2_MEMORY_USERPTR;
field = videobuf_next_field(q);
- retval = q->ops->buf_prepare(priv,q->read_buf,field);
+ retval = q->ops->buf_prepare(q,q->read_buf,field);
if (0 != retval)
goto done;
spin_lock_irqsave(q->irqlock,flags);
- q->ops->buf_queue(priv,q->read_buf);
+ q->ops->buf_queue(q,q->read_buf);
spin_unlock_irqrestore(q->irqlock,flags);
q->read_off = 0;
}
@@ -826,7 +826,7 @@ ssize_t videobuf_read_one(void *priv, st
if (STATE_ERROR == q->read_buf->state) {
/* catch I/O errors */
- q->ops->buf_release(priv,q->read_buf);
+ q->ops->buf_release(q,q->read_buf);
kfree(q->read_buf);
q->read_buf = NULL;
retval = -EIO;
@@ -845,7 +845,7 @@ ssize_t videobuf_read_one(void *priv, st
q->read_off += bytes;
if (q->read_off == q->read_buf->size) {
/* all data copied, cleanup */
- q->ops->buf_release(priv,q->read_buf);
+ q->ops->buf_release(q,q->read_buf);
kfree(q->read_buf);
q->read_buf = NULL;
}
@@ -855,43 +855,43 @@ ssize_t videobuf_read_one(void *priv, st
return retval;
}
-int videobuf_read_start(void *priv, struct videobuf_queue *q)
+int videobuf_read_start(struct videobuf_queue *q)
{
enum v4l2_field field;
unsigned long flags;
int count = 0, size = 0;
int err, i;
- q->ops->buf_setup(priv,&count,&size);
+ q->ops->buf_setup(q,&count,&size);
if (count < 2)
count = 2;
if (count > VIDEO_MAX_FRAME)
count = VIDEO_MAX_FRAME;
size = PAGE_ALIGN(size);
- err = videobuf_mmap_setup(priv, q, count, size, V4L2_MEMORY_USERPTR);
+ err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
if (err)
return err;
for (i = 0; i < count; i++) {
field = videobuf_next_field(q);
- err = q->ops->buf_prepare(priv,q->bufs[i],field);
+ err = q->ops->buf_prepare(q,q->bufs[i],field);
if (err)
return err;
list_add_tail(&q->bufs[i]->stream, &q->stream);
}
spin_lock_irqsave(q->irqlock,flags);
for (i = 0; i < count; i++)
- q->ops->buf_queue(priv,q->bufs[i]);
+ q->ops->buf_queue(q,q->bufs[i]);
spin_unlock_irqrestore(q->irqlock,flags);
q->reading = 1;
return 0;
}
-void videobuf_read_stop(void *priv, struct videobuf_queue *q)
+void videobuf_read_stop(struct videobuf_queue *q)
{
int i;
- videobuf_queue_cancel(priv,q);
+ videobuf_queue_cancel(q);
INIT_LIST_HEAD(&q->stream);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
@@ -903,7 +903,7 @@ void videobuf_read_stop(void *priv, stru
q->reading = 0;
}
-ssize_t videobuf_read_stream(void *priv, struct videobuf_queue *q,
+ssize_t videobuf_read_stream(struct videobuf_queue *q,
char __user *data, size_t count, loff_t *ppos,
int vbihack, int nonblocking)
{
@@ -917,7 +917,7 @@ ssize_t videobuf_read_stream(void *priv,
if (q->streaming)
goto done;
if (!q->reading) {
- retval = videobuf_read_start(priv,q);
+ retval = videobuf_read_start(q);
if (retval < 0)
goto done;
}
@@ -977,7 +977,7 @@ ssize_t videobuf_read_stream(void *priv,
list_add_tail(&q->read_buf->stream,
&q->stream);
spin_lock_irqsave(q->irqlock,flags);
- q->ops->buf_queue(priv,q->read_buf);
+ q->ops->buf_queue(q,q->read_buf);
spin_unlock_irqrestore(q->irqlock,flags);
q->read_buf = NULL;
}
@@ -990,7 +990,7 @@ ssize_t videobuf_read_stream(void *priv,
return retval;
}
-unsigned int videobuf_poll_stream(struct file *file, void *priv,
+unsigned int videobuf_poll_stream(struct file *file,
struct videobuf_queue *q,
poll_table *wait)
{
@@ -1004,7 +1004,7 @@ unsigned int videobuf_poll_stream(struct
struct videobuf_buffer, stream);
} else {
if (!q->reading)
- videobuf_read_start(priv,q);
+ videobuf_read_start(q);
if (!q->reading) {
rc = POLLERR;
} else if (NULL == q->read_buf) {
@@ -1045,29 +1045,30 @@ static void
videobuf_vm_close(struct vm_area_struct *vma)
{
struct videobuf_mapping *map = vma->vm_private_data;
+ struct videobuf_queue *q = map->q;
int i;
dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
map->count,vma->vm_start,vma->vm_end);
- /* down(&fh->lock); FIXME */
map->count--;
if (0 == map->count) {
- dprintk(1,"munmap %p\n",map);
+ dprintk(1,"munmap %p q=%p\n",map,q);
+ down(&q->lock);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
- if (NULL == map->q->bufs[i])
+ if (NULL == q->bufs[i])
continue;
- if (map->q->bufs[i])
+ if (q->bufs[i])
;
- if (map->q->bufs[i]->map != map)
+ if (q->bufs[i]->map != map)
continue;
- map->q->bufs[i]->map = NULL;
- map->q->bufs[i]->baddr = 0;
- map->q->ops->buf_release(vma->vm_file,map->q->bufs[i]);
+ q->bufs[i]->map = NULL;
+ q->bufs[i]->baddr = 0;
+ q->ops->buf_release(q,q->bufs[i]);
}
+ up(&q->lock);
kfree(map);
}
- /* up(&fh->lock); FIXME */
return;
}
@@ -1103,14 +1104,14 @@ static struct vm_operations_struct video
.nopage = videobuf_vm_nopage,
};
-int videobuf_mmap_setup(void *priv, struct videobuf_queue *q,
+int videobuf_mmap_setup(struct videobuf_queue *q,
unsigned int bcount, unsigned int bsize,
enum v4l2_memory memory)
{
unsigned int i;
int err;
- err = videobuf_mmap_free(priv,q);
+ err = videobuf_mmap_free(q);
if (0 != err)
return err;
@@ -1135,7 +1136,7 @@ int videobuf_mmap_setup(void *priv, stru
return 0;
}
-int videobuf_mmap_free(void *priv, struct videobuf_queue *q)
+int videobuf_mmap_free(struct videobuf_queue *q)
{
int i;
@@ -1145,15 +1146,15 @@ int videobuf_mmap_free(void *priv, struc
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
- q->ops->buf_release(priv,q->bufs[i]);
+ q->ops->buf_release(q,q->bufs[i]);
kfree(q->bufs[i]);
q->bufs[i] = NULL;
}
return 0;
}
-int videobuf_mmap_mapper(struct vm_area_struct *vma,
- struct videobuf_queue *q)
+int videobuf_mmap_mapper(struct videobuf_queue *q,
+ struct vm_area_struct *vma)
{
struct videobuf_mapping *map;
unsigned int first,last,size,i;
@@ -1222,8 +1223,8 @@ int videobuf_mmap_mapper(struct vm_area_
vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
vma->vm_private_data = map;
- dprintk(1,"mmap %p: %08lx-%08lx pgoff %08lx bufs %d-%d\n",
- map,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
+ dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
+ map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
retval = 0;
done:
--
#define printk(args...) fprintf(stderr, ## args)
Gerd Knorr <[email protected]> wrote:
>
> This is one more interface fix for the video-buf.c module, the first
> attempt on that wasn't that clever. Instead of passing the driver
> private data through all function calls I've just made that an element
> of the videobuf_queue struct which is passed around everythere _anyway_.
This patch throws a reject in videobuf_vm_close() because it's expecting
map->q->ops->buf_release(vma->vm_file,map->q->bufs[i]);
and not
map->q->ops->buf_release(vma->vm_file->private_data,map->q->bufs[i]);
I'll fix things up, but please check that.
On Mon, Nov 08, 2004 at 01:52:22PM -0800, Andrew Morton wrote:
> Gerd Knorr <[email protected]> wrote:
> >
> > This is one more interface fix for the video-buf.c module, the first
> > attempt on that wasn't that clever. Instead of passing the driver
> > private data through all function calls I've just made that an element
> > of the videobuf_queue struct which is passed around everythere _anyway_.
>
> This patch throws a reject in videobuf_vm_close() because it's expecting
>
> map->q->ops->buf_release(vma->vm_file,map->q->bufs[i]);
> and not
> map->q->ops->buf_release(vma->vm_file->private_data,map->q->bufs[i]);
>
> I'll fix things up, but please check that.
Someone (Peter Osterlund IIRC) mailed a patch with the "vma->vm_file" =>
"vma->vm_file->private_data" fix to lkml. Thats actually the place I
forgot on the first attempt and which causes the tvtime crashes
mentioned in the changelog.
My patches are built against a fresh linus bk tree, not against -mm, so
its probably just that patch being merged into -mm which causes the
rejects. No problem, my patch obsoletes this one-liner fix.
Gerd
--
#define printk(args...) fprintf(stderr, ## args)