[PATCH] v4l2: Improve decoding of VIDIOC_QBUF's arg.

[Philippe De Muyter]

* v4l2.c (v4l2_ioctl): Improve decoding of VIDIOC_QBUF's arg.
---
 v4l2.c | 38 +++++++++++++++++++++++++++-----------
 1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/v4l2.c b/v4l2.c
index 6377717..6201ddc 100644
--- a/v4l2.c
+++ b/v4l2.c
@@ -646,6 +646,10 @@ v4l2_ioctl(struct tcb *tcp, const unsigned int code, long arg)
 	case VIDIOC_DQBUF: {
 		struct v4l2_buffer b;
 
+		if (exiting(tcp) && syserror(tcp)) {
+			tprints("}");
+			return 1;
+		}
 		if (umove(tcp, arg, &b) < 0)
 			return 0;
 		if (entering(tcp)) {
@@ -653,10 +657,22 @@ v4l2_ioctl(struct tcb *tcp, const unsigned int code, long arg)
 			printxval(v4l2_buf_types, b.type, "V4L2_BUF_TYPE_???");
 			if (code != VIDIOC_DQBUF)
 				tprintf(", index=%u", b.index);
+			if (code == VIDIOC_QBUF) {
+				tprints(", memory=");
+				printxval(v4l2_memories, b.memory, "V4L2_MEMORY_???");
+				if (b.memory == V4L2_MEMORY_MMAP) {
+					tprintf(", m.offset=%#x", b.m.offset);
+				} else if (b.memory == V4L2_MEMORY_USERPTR) {
+					tprintf(", m.userptr=%#lx", b.m.userptr);
+				}
+				tprintf(", length=%u, bytesused=%u, flags=",
+					b.length, b.bytesused);
+				printflags(v4l2_buf_flags, b.flags, "V4L2_BUF_FLAG_???");
+			}
 		} else {
-			if (!syserror(tcp)) {
-				if (code == VIDIOC_DQBUF)
-					tprintf(", index=%u", b.index);
+			if (code == VIDIOC_DQBUF)
+				tprintf(", index=%u", b.index);
+			if (code != VIDIOC_QBUF) {
 				tprints(", memory=");
 				printxval(v4l2_memories, b.memory, "V4L2_MEMORY_???");
 
@@ -666,16 +682,16 @@ v4l2_ioctl(struct tcb *tcp, const unsigned int code, long arg)
 					tprintf(", m.userptr=%#lx", b.m.userptr);
 				}
 
-				tprintf(", length=%u, bytesused=%u, flags=",
+				tprintf(", length=%u, bytesused=%u",
 					b.length, b.bytesused);
-				printflags(v4l2_buf_flags, b.flags, "V4L2_BUF_FLAG_???");
-				if (code == VIDIOC_DQBUF)
-					tprintf(", timestamp = {%ju.%06ju}",
-						(uintmax_t)b.timestamp.tv_sec,
-						(uintmax_t)b.timestamp.tv_usec);
-				tprints(", ...");
 			}
-			tprints("}");
+			tprintf(code == VIDIOC_QBUF ? " => " : ", flags=");
+			printflags(v4l2_buf_flags, b.flags, "V4L2_BUF_FLAG_???");
+			if (code == VIDIOC_DQBUF)
+				tprintf(", timestamp = {%ju.%06ju}",
+					(uintmax_t)b.timestamp.tv_sec,
+					(uintmax_t)b.timestamp.tv_usec);
+			tprints(", ...}");
 		}
 		return 1;
 	}
-- 
1.8.4.5