[PATCH v3 5/6] cec-follower: Add version command

[Paul Elder <paul.elder@xxxxxxxxxxxxxxxx>]

Add a --version option to cec-follower to retrieve the version of
cec-follower.

Signed-off-by: Paul Elder <paul.elder@xxxxxxxxxxxxxxxx>

---
Changes in v3:
- embed PACKAGE_VERSION instead of string concatenation
---
 utils/cec-follower/cec-follower.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/utils/cec-follower/cec-follower.cpp b/utils/cec-follower/cec-follower.cpp
index 9cead57a..a09e1550 100644
--- a/utils/cec-follower/cec-follower.cpp
+++ b/utils/cec-follower/cec-follower.cpp
@@ -46,6 +46,7 @@ enum Option {
 	OptShowState = 's',
 	OptWallClock = 'w',
 	OptServiceByDigID = 128,
+	OptVersion,
 	OptLast = 256
 };
 
@@ -70,10 +71,16 @@ static struct option long_options[] = {
 	{ "wall-clock", no_argument, 0, OptWallClock },
 	{ "service-by-dig-id", no_argument, 0, OptServiceByDigID },
 	{ "ignore", required_argument, 0, OptIgnore },
+	{ "version", no_argument, 0, OptVersion },
 
 	{ 0, 0, 0, 0 }
 };
 
+static void version()
+{
+	printf("cec-follower %s\n", PACKAGE_VERSION);
+}
+
 static void usage()
 {
 	printf("Usage:\n"
@@ -93,6 +100,7 @@ static void usage()
 	       "                      Ignore messages from logical address <la> and opcode\n"
 	       "                      <opcode>. 'all' can be used for <la> or <opcode> to match\n"
 	       "                      all logical addresses or opcodes.\n"
+	       "  --version           Show version information\n"
 	       );
 }
 
@@ -427,6 +435,9 @@ int main(int argc, char **argv)
 			show_msgs = true;
 			show_state = true;
 			break;
+		case OptVersion:
+			version();
+			std::exit(EXIT_SUCCESS);
 		case ':':
 			fprintf(stderr, "Option '%s' requires a value\n",
 				argv[optind]);
-- 
2.27.0