settings: Add methods and a constructor to parse settings from strings

src/libstrongswan/settings/settings.c

@@ -37,9 +37,10 @@
 typedef struct private_settings_t private_settings_t;
 
 /**
- * Parse function provided by the generated parser.
+ * Parse functions provided by the generated parser.
  */
 bool settings_parser_parse_file(section_t *root, char *name);
+bool settings_parser_parse_string(section_t *root, char *settings);
 
 /**
  * Private data of settings
@@ -843,16 +844,17 @@ METHOD(settings_t, add_fallback, void,
 }
 
 /**
- * Load settings from files matching the given file pattern.
+ * Load settings from files matching the given file pattern or from a string.
  * All sections and values are added relative to "parent".
  * All files (even included ones) have to be loaded successfully.
  * If merge is FALSE the contents of parent are replaced with the parsed
  * contents, otherwise they are merged together.
  */
-static bool load_files_internal(private_settings_t *this, section_t *parent,
-								char *pattern, bool merge)
+static bool load_internal(private_settings_t *this, section_t *parent,
+						  char *pattern, bool merge, bool string)
 {
 	section_t *section;
+	bool loaded;
 
 	if (pattern == NULL || !pattern[0])
 	{	/* TODO: Clear parent if merge is FALSE? */
@@ -860,7 +862,9 @@ static bool load_files_internal(private_settings_t *this, section_t *parent,
 	}
 
 	section = settings_section_create(NULL);
-	if (!settings_parser_parse_file(section, pattern))
+	loaded = string ? settings_parser_parse_string(section, pattern) :
+					  settings_parser_parse_file(section, pattern);
+	if (!loaded)
 	{
 		settings_section_destroy(section, NULL);
 		return FALSE;
@@ -877,7 +881,7 @@ static bool load_files_internal(private_settings_t *this, section_t *parent,
 METHOD(settings_t, load_files, bool,
 	private_settings_t *this, char *pattern, bool merge)
 {
-	return load_files_internal(this, this->top, pattern, merge);
+	return load_internal(this, this->top, pattern, merge, FALSE);
 }
 
 METHOD(settings_t, load_files_section, bool,
@@ -894,7 +898,30 @@ METHOD(settings_t, load_files_section, bool,
 	{
 		return FALSE;
 	}
-	return load_files_internal(this, section, pattern, merge);
+	return load_internal(this, section, pattern, merge, FALSE);
+}
+
+METHOD(settings_t, load_string, bool,
+	private_settings_t *this, char *settings, bool merge)
+{
+	return load_internal(this, this->top, settings, merge, TRUE);
+}
+
+METHOD(settings_t, load_string_section, bool,
+	private_settings_t *this, char *settings, bool merge, char *key, ...)
+{
+	section_t *section;
+	va_list args;
+
+	va_start(args, key);
+	section = ensure_section(this, this->top, key, args);
+	va_end(args);
+
+	if (!section)
+	{
+		return FALSE;
+	}
+	return load_internal(this, section, settings, merge, TRUE);
 }
 
 METHOD(settings_t, destroy, void,
@@ -906,10 +933,7 @@ METHOD(settings_t, destroy, void,
 	free(this);
 }
 
-/*
- * see header file
- */
-settings_t *settings_create(char *file)
+static private_settings_t *settings_create_base()
 {
 	private_settings_t *this;
 
@@ -931,14 +955,37 @@ settings_t *settings_create(char *file)
 			.add_fallback = _add_fallback,
 			.load_files = _load_files,
 			.load_files_section = _load_files_section,
+			.load_string = _load_string,
+			.load_string_section = _load_string_section,
 			.destroy = _destroy,
 		},
 		.top = settings_section_create(NULL),
 		.contents = array_create(0, 0),
 		.lock = rwlock_create(RWLOCK_TYPE_DEFAULT),
 	);
+	return this;
+}
+
+/*
+ * see header file
+ */
+settings_t *settings_create(char *file)
+{
+	private_settings_t *this = settings_create_base();
 
 	load_files(this, file, FALSE);
 
 	return &this->public;
 }
+
+/*
+ * see header file
+ */
+settings_t *settings_create_string(char *settings)
+{
+	private_settings_t *this = settings_create_base();
+
+	load_string(this, settings, FALSE);
+
+	return &this->public;
+}

src/libstrongswan/settings/settings.h

@@ -334,6 +334,50 @@ struct settings_t {
 	bool (*load_files_section)(settings_t *this, char *pattern, bool merge,
 							   char *section, ...);
 
+	/**
+	 * Load settings from the given string.
+	 *
+	 * If merge is TRUE, existing sections are extended, existing values
+	 * replaced, by those found in the string. If it is FALSE, existing
+	 * sections are purged before reading the new config.
+	 *
+	 * @note If the string contains _include_ statements they should be
+	 * absolute paths.
+	 *
+	 * @note If any failures occur, no settings are added at all. So, it's all
+	 * or nothing.
+	 *
+	 * @param settings	string to parse
+	 * @param merge		TRUE to merge config with existing values
+	 * @return			TRUE, if settings were loaded successfully
+	 */
+	bool (*load_string)(settings_t *this, char *settings, bool merge);
+
+	/**
+	 * Load settings from the given string.
+	 *
+	 * If merge is TRUE, existing sections are extended, existing values
+	 * replaced, by those found in the string. If it is FALSE, existing
+	 * sections are purged before reading the new config.
+	 *
+	 * All settings are loaded relative to the given section. The section is
+	 * created, if it does not yet exist.
+	 *
+	 * @note If the string contains _include_ statements they should be
+	 * absolute paths.
+	 *
+	 * @note If any failures occur, no settings are added at all. So, it's all
+	 * or nothing.
+	 *
+	 * @param settings	string to parse
+	 * @param merge		TRUE to merge config with existing values
+	 * @param section	section name of parent section, printf style
+	 * @param ...		argument list for section
+	 * @return			TRUE, if settings were loaded successfully
+	 */
+	bool (*load_string_section)(settings_t *this, char *settings, bool merge,
+								char *section, ...);
+
 	/**
 	 * Destroy a settings instance.
 	 */
@@ -350,4 +394,14 @@ struct settings_t {
  */
 settings_t *settings_create(char *file);
 
+/**
+ * Load settings from a string.
+ *
+ * @note If parsing the file fails the object is still created.
+ *
+ * @param settings		string to read settings from
+ * @return				settings object, or NULL
+ */
+settings_t *settings_create_string(char *settings);
+
 #endif /** SETTINGS_H_ @}*/