[media] Fix mmap() example in the V4L2 API DocBook

Correct ioctl return value handling and fix coding style issues.

[mchehab@redhat.com: return -1 is OK, according with ioctl manpages. Reverting ioctl changes]
Signed-off-by: Pawel Osciak <pawel@osciak.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/Documentation/DocBook/v4l/io.xml b/Documentation/DocBook/v4l/io.xml
index d424886..a975043 100644 (file)
--- a/Documentation/DocBook/v4l/io.xml
+++ b/Documentation/DocBook/v4l/io.xml
@@ -141,63 +141,63 @@ struct {
 } *buffers;
 unsigned int i;
 
-memset (&reqbuf, 0, sizeof (reqbuf));
+memset(&reqbuf, 0, sizeof(reqbuf));
 reqbuf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 reqbuf.memory = V4L2_MEMORY_MMAP;
 reqbuf.count = 20;
 
 if (-1 == ioctl (fd, &VIDIOC-REQBUFS;, &reqbuf)) {
        if (errno == EINVAL)
-               printf ("Video capturing or mmap-streaming is not supported\n");
+               printf("Video capturing or mmap-streaming is not supported\n");
        else
-               perror ("VIDIOC_REQBUFS");
+               perror("VIDIOC_REQBUFS");
 
-       exit (EXIT_FAILURE);
+       exit(EXIT_FAILURE);
 }
 
 /* We want at least five buffers. */
 
 if (reqbuf.count < 5) {
        /* You may need to free the buffers here. */
-       printf ("Not enough buffer memory\n");
-       exit (EXIT_FAILURE);
+       printf("Not enough buffer memory\n");
+       exit(EXIT_FAILURE);
 }
 
-buffers = calloc (reqbuf.count, sizeof (*buffers));
-assert (buffers != NULL);
+buffers = calloc(reqbuf.count, sizeof(*buffers));
+assert(buffers != NULL);
 
 for (i = 0; i < reqbuf.count; i++) {
        &v4l2-buffer; buffer;
 
-       memset (&buffer, 0, sizeof (buffer));
+       memset(&buffer, 0, sizeof(buffer));
        buffer.type = reqbuf.type;
        buffer.memory = V4L2_MEMORY_MMAP;
        buffer.index = i;
 
        if (-1 == ioctl (fd, &VIDIOC-QUERYBUF;, &buffer)) {
-               perror ("VIDIOC_QUERYBUF");
-               exit (EXIT_FAILURE);
+               perror("VIDIOC_QUERYBUF");
+               exit(EXIT_FAILURE);
        }
 
        buffers[i].length = buffer.length; /* remember for munmap() */
 
-       buffers[i].start = mmap (NULL, buffer.length,
-                                PROT_READ | PROT_WRITE, /* recommended */
-                                MAP_SHARED,             /* recommended */
-                                fd, buffer.m.offset);
+       buffers[i].start = mmap(NULL, buffer.length,
+                               PROT_READ | PROT_WRITE, /* recommended */
+                               MAP_SHARED,             /* recommended */
+                               fd, buffer.m.offset);
 
        if (MAP_FAILED == buffers[i].start) {
                /* If you do not exit here you should unmap() and free()
                   the buffers mapped so far. */
-               perror ("mmap");
-               exit (EXIT_FAILURE);
+               perror("mmap");
+               exit(EXIT_FAILURE);
        }
 }
 
 /* Cleanup. */
 
 for (i = 0; i < reqbuf.count; i++)
-       munmap (buffers[i].start, buffers[i].length);
+       munmap(buffers[i].start, buffers[i].length);
       </programlisting>
     </example>