* bit indexes. "..end" may be omitted to indicate a single bit. "start..end"
* may both be omitted (the [] are still required) to indicate an entire
* field. */
-char *
+char * WARN_UNUSED_RESULT
mf_parse_subfield__(struct mf_subfield *sf, const char **sp)
{
const struct mf_field *field;
return NULL;
}
-/* Parses a subfield from the beginning of 's' into 'sf'. Returns the first
- * byte in 's' following the parsed string.
- *
- * Exits with an error message if 's' has incorrect syntax.
+/* Parses a subfield from the entirety of 's' into 'sf'. Returns NULL if
+ * successful, otherwise a malloc()'d string describing the error. The caller
+ * is responsible for freeing the returned string.
*
* The syntax parsed from 's' takes the form "header[start..end]" where
* 'header' is the name of an NXM field and 'start' and 'end' are (inclusive)
* bit indexes. "..end" may be omitted to indicate a single bit. "start..end"
* may both be omitted (the [] are still required) to indicate an entire
* field. */
-const char *
+char * WARN_UNUSED_RESULT
mf_parse_subfield(struct mf_subfield *sf, const char *s)
{
- char *msg = mf_parse_subfield__(sf, &s);
- if (msg) {
- ovs_fatal(0, "%s", msg);
+ char *error = mf_parse_subfield__(sf, &s);
+ if (!error && s[0]) {
+ error = xstrdup("unexpected input following field syntax");
}
- return s;
+ return error;
}
void