Add function ast_false, like ast_true

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@2289 65c4cc65-6c06-0410-ace0-fbb531ad65f3

config.c

@@ -128,6 +128,20 @@ int ast_true(char *s)
 	return 0;
 }
 
+int ast_false(char *s)
+{
+	if (!s)
+		return 0;
+	/* Determine if this is a false value */
+	if (!strcasecmp(s, "no") ||
+	    !strcasecmp(s, "false") ||
+		!strcasecmp(s, "n") ||
+		!strcasecmp(s, "f") ||
+		!strcasecmp(s, "0"))
+			return -1;
+	return 0;
+}
+
 struct ast_variable *ast_variable_browse(struct ast_config *config, char *category)
 {
 	struct ast_category *cat;

include/asterisk/config.h

@@ -87,6 +87,14 @@ char *ast_variable_retrieve(struct ast_config *config, char *category, char *val
  */
 int ast_true(char *val);
 
+//! Make sure something is false
+/*!
+ * Determine falseness of a boolean value.
+ * This function checks to see whether a string passed to it is an indication of a negatirve value.  It checks to see if the string is "no", "false", "n", "f", and "0".  
+ * Returns 0 if the value of s is a NULL pointer, 0 on "truth", and -1 on falsehood.
+ */
+int ast_false(char *val);
+
 //! Check for category duplicates
 /*!
  * \param config which config to use