From f74769e77e2e51b568cf2061e7703eec1405f06d Mon Sep 17 00:00:00 2001
From: Peter Hutterer <peter.hutterer@who-t.net>
Date: Wed, 24 Jun 2015 15:12:54 +1000
Subject: [PATCH] tools: add --grab option

Issues an EVIOCGRAB on the openend devices, providing exclusive access. Makes
it easier for debugging, so moving the pointer doesn't accidentally trigger
other stuff.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
---
 tools/shared.c | 17 ++++++++++++++++-
 tools/shared.h |  1 +
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/tools/shared.c b/tools/shared.c
index 0bb03b1b..64544c5c 100644
--- a/tools/shared.c
+++ b/tools/shared.c
@@ -40,6 +40,7 @@
 enum options {
 	OPT_DEVICE,
 	OPT_UDEV,
+	OPT_GRAB,
 	OPT_HELP,
 	OPT_VERBOSE,
 	OPT_TAP_ENABLE,
@@ -95,6 +96,7 @@ tools_usage()
 	       "is not explicitly specified it is left at each device's default.\n"
 	       "\n"
 	       "Other options:\n"
+	       "--grab .......... Exclusively grab all openend devices\n"
 	       "--verbose ....... Print debugging output.\n"
 	       "--help .......... Print this help.\n",
 		program_invocation_short_name);
@@ -122,14 +124,17 @@ tools_init_context(struct tools_context *context)
 }
 
 int
-tools_parse_args(int argc, char **argv, struct tools_options *options)
+tools_parse_args(int argc, char **argv, struct tools_context *context)
 {
+	struct tools_options *options = &context->options;
+
 	while (1) {
 		int c;
 		int option_index = 0;
 		static struct option opts[] = {
 			{ "device", 1, 0, OPT_DEVICE },
 			{ "udev", 0, 0, OPT_UDEV },
+			{ "grab", 0, 0, OPT_GRAB },
 			{ "help", 0, 0, OPT_HELP },
 			{ "verbose", 0, 0, OPT_VERBOSE },
 			{ "enable-tap", 0, 0, OPT_TAP_ENABLE },
@@ -171,6 +176,9 @@ tools_parse_args(int argc, char **argv, struct tools_options *options)
 				if (optarg)
 					options->seat = optarg;
 				break;
+			case OPT_GRAB:
+				options->grab = 1;
+				break;
 			case OPT_VERBOSE:
 				options->verbose = 1;
 				break;
@@ -352,10 +360,17 @@ open_device(const struct libinput_interface *interface,
 static int
 open_restricted(const char *path, int flags, void *user_data)
 {
+	const struct tools_context *context = user_data;
 	int fd = open(path, flags);
+
 	if (fd < 0)
 		fprintf(stderr, "Failed to open %s (%s)\n",
 			path, strerror(errno));
+	else if (context->options.grab &&
+		 ioctl(fd, EVIOCGRAB, (void*)1) == -1)
+		fprintf(stderr, "Grab requested, but failed for %s (%s)\n",
+			path, strerror(errno));
+
 	return fd < 0 ? -errno : fd;
 }
 
diff --git a/tools/shared.h b/tools/shared.h
index 442d7cd3..a848e2d1 100644
--- a/tools/shared.h
+++ b/tools/shared.h
@@ -35,6 +35,7 @@ struct tools_options {
 	enum tools_backend backend;
 	const char *device; /* if backend is BACKEND_DEVICE */
 	const char *seat; /* if backend is BACKEND_UDEV */
+	int grab; /* EVIOCGRAB */
 
 	int verbose;
 	int tapping;