tools lib traceevent: Make plugin options either string or boolean

When a plugin option is defined, by default it is a boolean (true or false).
If the option is something else, then it needs to set its "value" field to
a default string other than NULL (can be just ""). If the value is not set
then the option is considered boolean, and the updating of the option value
will be handled accordingly.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 54 insertions, 6 deletions

diff --git a/event-plugin.c b/event-plugin.c
index 136162c0..a16756ae 100644
--- a/event-plugin.c
+++ b/event-plugin.c
@@ -18,6 +18,7 @@
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
 
+#include <ctype.h>
 #include <stdio.h>
 #include <string.h>
 #include <dlfcn.h>
@@ -49,6 +50,52 @@ struct plugin_list {
 	void			*handle;
 };
 
+static void lower_case(char *str)
+{
+	if (!str)
+		return;
+	for (; *str; str++)
+		*str = tolower(*str);
+}
+
+static int update_option_value(struct pevent_plugin_option *op, const char *val)
+{
+	char *op_val;
+
+	if (!val) {
+		/* toggle, only if option is boolean */
+		if (op->value)
+			/* Warn? */
+			return 0;
+		op->set ^= 1;
+		return 0;
+	}
+
+	/*
+	 * If the option has a value then it takes a string
+	 * otherwise the option is a boolean.
+	 */
+	if (op->value) {
+		op->value = val;
+		return 0;
+	}
+
+	/* Option is boolean, must be either "1", "0", "true" or "false" */
+
+	op_val = strdup(val);
+	if (!op_val)
+		return -1;
+	lower_case(op_val);
+
+	if (strcmp(val, "1") == 0 || strcmp(val, "true") == 0)
+		op->set = 1;
+	else if (strcmp(val, "0") == 0 || strcmp(val, "false") == 0)
+		op->set = 0;
+	free(op_val);
+
+	return 0;
+}
+
 /**
  * traceevent_plugin_list_options - get list of plugin options
  *
@@ -120,6 +167,7 @@ update_option(const char *file, struct pevent_plugin_option *option)
 {
 	struct trace_plugin_options *op;
 	char *plugin;
+	int ret = 0;
 
 	if (option->plugin_alias) {
 		plugin = strdup(option->plugin_alias);
@@ -144,9 +192,10 @@ update_option(const char *file, struct pevent_plugin_option *option)
 		if (strcmp(op->option, option->name) != 0)
 			continue;
 
-		option->value = op->value;
-		option->set ^= 1;
-		goto out;
+		ret = update_option_value(option, op->value);
+		if (ret)
+			goto out;
+		break;
 	}
 
 	/* first look for unnamed options */
@@ -156,14 +205,13 @@ update_option(const char *file, struct pevent_plugin_option *option)
 		if (strcmp(op->option, option->name) != 0)
 			continue;
 
-		option->value = op->value;
-		option->set ^= 1;
+		ret = update_option_value(option, op->value);
 		break;
 	}
 
  out:
 	free(plugin);
-	return 0;
+	return ret;
 }
 
 /**