v4l2: v4l2_camera_file: Store file description

Create a string that describe the file from the path and file
descriptor. This will be used in log messages to clearly identify which
file an operation is related to.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>

1 files changed, 27 insertions, 1 deletions

diff --git a/src/v4l2/v4l2_camera_file.cpp b/src/v4l2/v4l2_camera_file.cpp
index a07679b5..0a41587c 100644
--- a/src/v4l2/v4l2_camera_file.cpp
+++ b/src/v4l2/v4l2_camera_file.cpp
@@ -7,20 +7,46 @@
 
 #include "v4l2_camera_file.h"
 
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+
 #include <linux/videodev2.h>
 
 #include "v4l2_camera_proxy.h"
 
 using namespace libcamera;
 
-V4L2CameraFile::V4L2CameraFile(int efd, bool nonBlocking, V4L2CameraProxy *proxy)
+V4L2CameraFile::V4L2CameraFile(int dirfd, const char *path, int efd,
+			       bool nonBlocking, V4L2CameraProxy *proxy)
 	: proxy_(proxy), nonBlocking_(nonBlocking), efd_(efd),
 	  priority_(V4L2_PRIORITY_DEFAULT)
 {
 	proxy_->open(this);
+
+	if (path[0] != '/') {
+		if (dirfd == AT_FDCWD) {
+			char *cwd = getcwd(nullptr, 0);
+			if (cwd) {
+				description_ = std::string(cwd) + "/";
+				free(cwd);
+			} else {
+				description_ = std::string("(unreachable)/");
+			}
+		} else {
+			description_ = "(dirfd:" + std::to_string(dirfd) + ")/";
+		}
+	}
+
+	description_ += std::string(path) + " (fd:" + std::to_string(efd) + ")";
 }
 
 V4L2CameraFile::~V4L2CameraFile()
 {
 	proxy_->close(this);
 }
+
+const std::string &V4L2CameraFile::description() const
+{
+	return description_;
+}