Support reading --debug et al from process command line

Up until now Finit has only read /proc/cmdline to determine debug level,
single user mode, etc.  This patch is one in a series to make enable it
to run also in containers.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/conf.c

@@ -59,12 +59,31 @@ static TAILQ_HEAD(head, conf_change) conf_change_list = TAILQ_HEAD_INITIALIZER(c
 static int parse_conf(char *file);
 static void drop_changes(void);
 
-void conf_parse_cmdline(void)
+static void parse_arg(char *arg, int *dbg)
+{
+	/* Catches finit_debug (deprecated), --debug, and debug */
+	if (strstr(arg, "debug"))
+		*dbg = 1;
+
+	if (string_compare(arg, "rescue") || string_compare(arg, "recover"))
+		rescue = 1;
+
+	if (string_compare(arg, "single") || string_compare(arg, "S"))
+		single = 1;
+
+	if (string_compare(arg, "splash"))
+		splash = 1;
+}
+
+void conf_parse_cmdline(int argc, char *argv[])
 {
 	int dbg = 0;
 	FILE *fp;
 	char line[LINE_SIZE], *cmdline, *tok;
 
+	for (int i = 1; i < argc; i++)
+		parse_arg(argv[i], &dbg);
+
 	fp = fopen("/proc/cmdline", "r");
 	if (!fp)
 		goto done;
@@ -79,19 +98,7 @@ void conf_parse_cmdline(void)
 
 	while ((tok = strtok(cmdline, " \t"))) {
 		cmdline = NULL;
-
-		/* Catches finit_debug (deprecated), --debug, and debug */
-		if (strstr(tok, "debug"))
-			dbg = 1;
-
-		if (string_compare(tok, "rescue") || string_compare(tok, "recover"))
-			rescue = 1;
-
-		if (string_compare(tok, "single") || string_compare(tok, "S"))
-			single = 1;
-
-		if (string_compare(tok, "splash"))
-			splash = 1;
+		parse_arg(tok, &dbg);
 	}
 	fclose(fp);
 

src/conf.h

@@ -40,7 +40,7 @@ int  conf_any_change      (void);
 int  conf_changed         (char *file);
 int  conf_monitor         (uev_ctx_t *ctx);
 
-void conf_parse_cmdline   (void);
+void conf_parse_cmdline   (int argc, char *argv[]);
 int  conf_parse_runlevels (char *runlevels);
 void conf_parse_cond      (svc_t *svc, char *cond);
 

src/finit.c

@@ -292,6 +292,12 @@ int main(int argc, char *argv[])
 	if (getpid() != 1)
 		return client(argc, argv);
 
+	/*
+	 * Parse kernel command line (debug, rescue, splash, etc.)
+	 * Also calls log_init() to set correct log level
+	 */
+	conf_parse_cmdline(argc, argv);
+
 	/*
 	 * Hide command line arguments from ps (in particular for
 	 * forked children that don't execv()).  This is an ugly
@@ -320,12 +326,6 @@ int main(int argc, char *argv[])
 	chdir("/");
 	umask(0);
 
-	/*
-	 * Parse kernel command line (debug, rescue, splash, etc.)
-	 * Also calls log_init() to set correct log level
-	 */
-	conf_parse_cmdline();
-
 	/* Set up canvas */
 	if (!rescue && !log_is_debug())
 		screen_init();