-/*
- * Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
/** \file filter_common.c Common helper functions for filter input/output. */
#include "string.h"
/** Iterate over all filters. */
-#define FOR_EACH_FILTER(j) for (j = 1; lls_cmd(j, filter_cmd_suite); j++)
+#define FOR_EACH_FILTER(j) for (j = 1; FILTER_CMD(j); j++)
/**
* Obtain a reference to a filter structure.
*
* \param filter_num Between zero and NUM_SUPPORTED_FILTERS, inclusively.
*
- * \return Pointer to the filter identified by the given filter number.
+ * \return Pointer to the filter identified by the given filter number, or
+ * NULL if the filter number is out of range.
*
- * It is a fatal error if the given number is out of range. In this case
- * the function aborts.
+ * \sa filter_name().
*/
const struct filter *filter_get(int filter_num)
{
- assert(filter_num >= 1);
- assert(filter_num <= LSG_NUM_FILTER_CMD_SUBCOMMANDS);
+ if (filter_num < 1 || filter_num > LSG_NUM_FILTER_CMD_SUBCOMMANDS)
+ return NULL;
return lls_user_data(FILTER_CMD(filter_num));
}
return lls_user_data(FILTER_CMD(filter_num));
}
+/**
+ * Return the name of a filter, given its number.
+ *
+ * \param filter_num See \ref filter_get().
+ *
+ * \return A pointer to a string literal, or NULL if filter_num is out of
+ * range. The caller must not attempt to call free(3) on the returned pointer.
+ */
const char *filter_name(int filter_num)
{
+ if (filter_num < 1 || filter_num > LSG_NUM_FILTER_CMD_SUBCOMMANDS)
+ return NULL;
return lls_command_name(FILTER_CMD(filter_num));
}