much work (options, rc script, make install, etc etc).

1 files changed, 105 insertions, 21 deletions

diff --git a/marsond.c b/marsond.c
index 228310d..885a3e2 100644
--- a/marsond.c
+++ b/marsond.c
@@ -1,3 +1,5 @@
+#define _DEFAULT_SOURCE /* for getopt() and optarg */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -9,19 +11,17 @@
 #include <linux/input.h>
 #include <linux/uinput.h>
 
-#define DELAY_MS 30
+#define VERSION "0.0.1"
 
-#define DEFAULT_KBD "/dev/input/by-id/usb-Marson_Marson_Keyboard_and_Mouse_Link_Ver:ps2120L-event-kbd"
+#define DEFAULT_DELAY_MS 30
 
-/* eventually, this will take options to set the device and
-	delay for the Enter key, and will have an rc script to
-	start it...? */
+#define DEFAULT_KBD "/dev/input/by-id/usb-Marson_Marson_Keyboard_and_Mouse_Link_Ver:ps2120L-event-kbd"
 
 const char *self;
 
-int debugging = 1;
-
-const char *keyboard_dev;
+int debugging = 0;                      /* -v */
+const char *keyboard_dev = DEFAULT_KBD; /* -k */
+int delay_ms = DEFAULT_DELAY_MS;        /* -d */
 
 /* variadic macros are apparently C99 and not just a GNU extension */
 void logmsg(const char *prefix, const char *fmt, ...) {
@@ -34,8 +34,8 @@ void logmsg(const char *prefix, const char *fmt, ...) {
 }
 
 #define die(fmt,  ...)  { logmsg("fatal",   fmt, ##__VA_ARGS__); exit(1); };
-#define warn(fmt, ...)  logmsg("warning", fmt, ##__VA_ARGS__);
-#define info(fmt, ...)  logmsg("info",    fmt, ##__VA_ARGS__);
+#define warn(fmt, ...)  { logmsg("warning", fmt, ##__VA_ARGS__); };
+#define info(fmt, ...)  { logmsg("info",    fmt, ##__VA_ARGS__); };
 #define debug(fmt, ...) { if(debugging) logmsg("debug",    fmt, ##__VA_ARGS__); };
 
 void set_self(const char *argv0) {
@@ -45,17 +45,93 @@ void set_self(const char *argv0) {
    if(p) self = p + 1;
 }
 
+void print_help(void) {
+	/* helptext comes from usage.c, which gets generated by mkusage.pl,
+	   from the content in the the .rst file. */
+	extern const char *helptext[];
+
+	const char **helpline;
+
+	puts("marsond " VERSION ", by B. Watson <urchlay@slackware.uk>, WTFPL");
+	puts("Usage:");
+
+	for(helpline = helptext; *helpline; helpline++)
+		puts(*helpline);
+}
+
+void version(void) {
+	puts(VERSION);
+}
+
+void parse_args(int argc, char **argv) {
+	int opt;
+
+	opterr = 0;
+
+   if(argc >= 2) {
+      if(strcmp(argv[1], "--help") == 0) {
+         print_help();
+         exit(0);
+      } else if(strcmp(argv[1], "--version") == 0) {
+         version();
+         exit(0);
+      }
+   }
+
+	while( (opt = getopt(argc, argv, "d:hk:vV")) != -1) {
+		switch(opt) {
+			case 'v': debugging++;             break;
+			case 'd': delay_ms = atoi(optarg); break;
+			case 'k': keyboard_dev = optarg;   break;
+			case 'h': print_help(); exit(0);   break;
+			case 'V': version(); exit(0);      break;
+			case '?': die("invalid option (try --help)"); break;
+			default:  print_help(); exit(1);              break;
+		}
+	}
+
+	if(delay_ms < 1) die("invalid -d argument");
+}
+
+void daemonize(void) {
+	int pid;
+
+	pid = fork();
+	if(pid < 0) {
+		die("fork() failed");
+	} else if(pid) {
+		/* parent */
+		exit(0);
+	}
+
+	/* we are the child here */
+	setsid();
+
+	pid = fork();
+	if(pid < 0) {
+		die("fork() failed");
+	} else if(pid) {
+		/* 2nd generation parent */
+		info("forked to background, PID %d\n", pid);
+		exit(0);
+	}
+
+	/* we are the grandchild here */
+	chdir("/");
+	close(0);
+	close(1);
+	close(2);
+}
+
 int main(int argc, char **argv) {
 	int infd, outfd, i;
 	struct uinput_user_dev dev;
 	struct input_event ev;
-	static struct input_event deferred_ev;
 
 	set_self(argv[0]);
 	debug("starting up");
 
-	if(!keyboard_dev)
-		keyboard_dev = DEFAULT_KBD;
+	parse_args(argc, argv);
 
 	if((outfd = open("/dev/uinput", O_WRONLY | O_NONBLOCK)) >= 0) {
 		debug("opened /dev/uinput");
@@ -88,12 +164,13 @@ int main(int argc, char **argv) {
 			die("UI_SET_EVBIT failed: %s", strerror(errno));
 		}
 	}
+	debug("UI_SET_KEYBIT OK");
 
 	memset(&dev, 0, sizeof(dev));
 	snprintf(dev.name, UINPUT_MAX_NAME_SIZE, "marsond virtual keyboard");
-	dev.id.bustype == BUS_USB;
-	dev.id.vendor = 1;
-	dev.id.product = 1;
+	dev.id.bustype = BUS_USB;
+	dev.id.vendor =  0x69;
+	dev.id.product = 0x666;
 	dev.id.version = 1;
 
 	if(write(outfd, &dev, sizeof(dev)) >= 0) {
@@ -108,25 +185,32 @@ int main(int argc, char **argv) {
 		die("UI_DEV_CREATE failed: %s", strerror(errno));
 	}
 
+	if(!debugging) daemonize();
+
+	/* note: don't call die() unless debugging is true, since daemonize()
+	   closes our stderr (there's nowhere for the error message to print). */
+
 	while(1) {
 		if(read(infd, &ev, sizeof(ev)) < 0) {
-			die("read from %s failed: %s", keyboard_dev, strerror(errno));
+			if(debugging)
+				die("read from %s failed: %s", keyboard_dev, strerror(errno));
 		}
 
 		debug("event: type %d, code %d, value %d\n",
 				ev.type, ev.code, ev.value);
 
 		if(ev.type == EV_KEY && ev.code == KEY_ENTER && ev.value == 0) {
-			debug("got Enter key release, delaying %d ms", DELAY_MS);
-			usleep(DELAY_MS * 1000);
+			debug("got Enter key release, delaying %d ms", delay_ms);
+			usleep(delay_ms * 1000);
 		}
 
 		if(write(outfd, &ev, sizeof(ev)) < 0) {
-			die("write to /dev/uinput failed: %s", strerror(errno));
+			if(debugging)
+				die("write to /dev/uinput failed: %s", strerror(errno));
 		}
 	}
 
-	exit(0);
+	exit(1);
 }
 
 /*