bus: add iterator to find a bus

[dpdk.git] / lib / librte_eal / common / include / rte_bus.h

diff --git a/lib/librte_eal/common/include/rte_bus.h b/lib/librte_eal/common/include/rte_bus.h
index 5f47b829b9d99f591424a93e5f63c31d4bed40fa..c52b65b1f1f3c6e924511527cb90fc41afc2c1f9 100644 (file)
--- a/lib/librte_eal/common/include/rte_bus.h
+++ b/lib/librte_eal/common/include/rte_bus.h
@@ -140,6 +140,48 @@ int rte_bus_probe(void);
  */
 void rte_bus_dump(FILE *f);
 
+/**
+ * Bus comparison function.
+ *
+ * @param bus
+ *     Bus under test.
+ *
+ * @param data
+ *     Data to compare against.
+ *
+ * @return
+ *     0 if the bus matches the data.
+ *     !0 if the bus does not match.
+ *     <0 if ordering is possible and the bus is lower than the data.
+ *     >0 if ordering is possible and the bus is greater than the data.
+ */
+typedef int (*rte_bus_cmp_t)(const struct rte_bus *bus, const void *data);
+
+/**
+ * Bus iterator to find a particular bus.
+ *
+ * This function compares each registered bus to find one that matches
+ * the data passed as parameter.
+ *
+ * If the comparison function returns zero this function will stop iterating
+ * over any more buses. To continue a search the bus of a previous search can
+ * be passed via the start parameter.
+ *
+ * @param start
+ *     Starting point for the iteration.
+ *
+ * @param cmp
+ *     Comparison function.
+ *
+ * @param data
+ *      Data to pass to comparison function.
+ *
+ * @return
+ *      A pointer to a rte_bus structure or NULL in case no bus matches
+ */
+struct rte_bus *rte_bus_find(const struct rte_bus *start, rte_bus_cmp_t cmp,
+                            const void *data);
+
 /**
  * Helper for Bus registration.
  * The constructor has higher priority than PMD constructors.