Let oeffis-demo-tool start ei-demo-client optionally

tools/oeffis-demo-tool.c

@@ -29,6 +29,7 @@
 #include "config.h"
 
 #include <assert.h>
+#include <getopt.h>
 #include <signal.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -71,9 +72,80 @@ start_debug_events(int fd)
 	}
 }
 
+static void
+start_demo_client(int fd)
+{
+	pid_t pid = fork();
+	assert(pid != -1);
+
+	if (pid == 0) {
+		_cleanup_free_ char *fdstr = xaprintf("%d", fd);
+		execl(MESON_BUILDDIR "/ei-demo-client",
+		      "ei-demo-client",
+		      "--socketfd", fdstr, NULL);
+		fprintf(stderr, "Failed to fork: %m\n");
+		exit(1);
+	}
+}
+
+static void
+usage(FILE *fp, const char *argv0)
+{
+	fprintf(fp,
+		"Usage: %s [--client=debug-events|demo-client]\n"
+		"\n"
+		"Connect to the EIS implementation via the remote desktop portal.\n"
+		"Afterwards the specified action is taken.\n"
+		"\n"
+		"Options:\n"
+		" --client	the tool to launch after connecting to the eis implementation,\n"
+		"		one of debug-events (default) or demo-client\n",
+		argv0);
+}
+
 int
 main(int argc, char **argv)
 {
+	enum {
+		DEBUG,
+		CLIENT,
+	} action = DEBUG;
+
+	while (1) {
+		enum {
+			OPT_CLIENT,
+		};
+		static struct option long_opts[] = {
+			{"client",	required_argument, 0, OPT_CLIENT},
+			{"help",	no_argument, 0, 'h'},
+			{.name = NULL},
+		};
+
+		int optind = 0;
+		int c = getopt_long(argc, argv, "h", long_opts, &optind);
+		if (c == -1)
+			break;
+
+		switch(c) {
+		case 'h':
+			usage(stdout, argv[0]);
+			return EXIT_SUCCESS;
+		case OPT_CLIENT:
+			action = DEBUG;
+			if (strcmp(optarg, "debug-events") == 0) {
+				action = DEBUG;
+				break;
+			} else if (strcmp(optarg, "demo-client") == 0) {
+				action = CLIENT;
+				break;
+			}
+			_fallthrough_;
+		default:
+			usage(stderr, argv[0]);
+			return EXIT_FAILURE;
+		}
+	}
+
 	_unref_(oeffis) *oeffis = oeffis_new(NULL);
 
 	signal(SIGINT, sighandler);
@@ -108,8 +180,15 @@ main(int argc, char **argv)
 			 * cause the compositor or the portal to invalidate
 			 * our EIS fd.
 			 */
+			switch (action) {
+			case DEBUG:
 				start_debug_events(eisfd);
 				break;
+			case CLIENT:
+				start_demo_client(eisfd);
+				break;
+			}
+			break;
 		}
 		case OEFFIS_EVENT_DISCONNECTED:
 			fprintf(stderr, "Disconnected: %s\n", oeffis_get_error_message(oeffis));