ethdev: add flow API item/action name conversion

This provides a means for applications to retrieve the name of flow
pattern items and actions.

Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
Acked-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>

diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
index 964cf9c..1b17f6e 100644 (file)
--- a/doc/guides/prog_guide/rte_flow.rst
+++ b/doc/guides/prog_guide/rte_flow.rst
@@ -2437,6 +2437,7 @@ operations include:
 - Attributes, pattern item or action duplication.
 - Duplication of an entire pattern or list of actions.
 - Duplication of a complete flow rule description.
+- Pattern item or action name retrieval.
 
 Caveats
 -------

diff --git a/lib/librte_ethdev/rte_flow.c b/lib/librte_ethdev/rte_flow.c
index 4fd6cfa..c3ff7e7 100644 (file)
--- a/lib/librte_ethdev/rte_flow.c
+++ b/lib/librte_ethdev/rte_flow.c
@@ -11,6 +11,7 @@
 #include <rte_common.h>
 #include <rte_errno.h>
 #include <rte_branch_prediction.h>
+#include <rte_string_fns.h>
 #include "rte_ethdev.h"
 #include "rte_flow_driver.h"
 #include "rte_flow.h"
@@ -679,6 +680,60 @@ rte_flow_conv_rule(struct rte_flow_conv_rule *dst,
        return off;
 }
 
+/**
+ * Retrieve the name of a pattern item/action type.
+ *
+ * @param is_action
+ *   Nonzero when @p src represents an action type instead of a pattern item
+ *   type.
+ * @param is_ptr
+ *   Nonzero to write string address instead of contents into @p dst.
+ * @param[out] dst
+ *   Destination buffer. Can be NULL if @p size is zero.
+ * @param size
+ *   Size of @p dst in bytes.
+ * @param[in] src
+ *   Depending on @p is_action, source pattern item or action type cast as a
+ *   pointer.
+ * @param[out] error
+ *   Perform verbose error reporting if not NULL.
+ *
+ * @return
+ *   A positive value representing the number of bytes needed to store the
+ *   name or its address regardless of @p size on success (@p buf contents
+ *   are truncated to @p size if not large enough), a negative errno value
+ *   otherwise and rte_errno is set.
+ */
+static int
+rte_flow_conv_name(int is_action,
+                  int is_ptr,
+                  char *dst,
+                  const size_t size,
+                  const void *src,
+                  struct rte_flow_error *error)
+{
+       struct desc_info {
+               const struct rte_flow_desc_data *data;
+               size_t num;
+       };
+       static const struct desc_info info_rep[2] = {
+               { rte_flow_desc_item, RTE_DIM(rte_flow_desc_item), },
+               { rte_flow_desc_action, RTE_DIM(rte_flow_desc_action), },
+       };
+       const struct desc_info *const info = &info_rep[!!is_action];
+       unsigned int type = (uintptr_t)src;
+
+       if (type >= info->num)
+               return rte_flow_error_set
+                       (error, EINVAL, RTE_FLOW_ERROR_TYPE_UNSPECIFIED, NULL,
+                        "unknown object type to retrieve the name of");
+       if (!is_ptr)
+               return strlcpy(dst, info->data[type].name, size);
+       if (size >= sizeof(const char **))
+               *((const char **)dst) = info->data[type].name;
+       return sizeof(const char **);
+}
+
 /** Helper function to convert flow API objects. */
 int
 rte_flow_conv(enum rte_flow_conv_op op,
@@ -708,6 +763,14 @@ rte_flow_conv(enum rte_flow_conv_op op,
                return rte_flow_conv_actions(dst, size, src, 0, error);
        case RTE_FLOW_CONV_OP_RULE:
                return rte_flow_conv_rule(dst, size, src, error);
+       case RTE_FLOW_CONV_OP_ITEM_NAME:
+               return rte_flow_conv_name(0, 0, dst, size, src, error);
+       case RTE_FLOW_CONV_OP_ACTION_NAME:
+               return rte_flow_conv_name(1, 0, dst, size, src, error);
+       case RTE_FLOW_CONV_OP_ITEM_NAME_PTR:
+               return rte_flow_conv_name(0, 1, dst, size, src, error);
+       case RTE_FLOW_CONV_OP_ACTION_NAME_PTR:
+               return rte_flow_conv_name(1, 1, dst, size, src, error);
        }
        return rte_flow_error_set
                (error, ENOTSUP, RTE_FLOW_ERROR_TYPE_UNSPECIFIED, NULL,

diff --git a/lib/librte_ethdev/rte_flow.h b/lib/librte_ethdev/rte_flow.h
index 1288e76..052ceef 100644 (file)
--- a/lib/librte_ethdev/rte_flow.h
+++ b/lib/librte_ethdev/rte_flow.h
@@ -2043,6 +2043,62 @@ enum rte_flow_conv_op {
         *   @code struct rte_flow_conv_rule * @endcode
         */
        RTE_FLOW_CONV_OP_RULE,
+
+       /**
+        * Convert item type to its name string.
+        *
+        * Writes a NUL-terminated string to @p dst. Like snprintf(), the
+        * returned value excludes the terminator which is always written
+        * nonetheless.
+        *
+        * - @p src type:
+        *   @code (const void *)enum rte_flow_item_type @endcode
+        * - @p dst type:
+        *   @code char * @endcode
+        **/
+       RTE_FLOW_CONV_OP_ITEM_NAME,
+
+       /**
+        * Convert action type to its name string.
+        *
+        * Writes a NUL-terminated string to @p dst. Like snprintf(), the
+        * returned value excludes the terminator which is always written
+        * nonetheless.
+        *
+        * - @p src type:
+        *   @code (const void *)enum rte_flow_action_type @endcode
+        * - @p dst type:
+        *   @code char * @endcode
+        **/
+       RTE_FLOW_CONV_OP_ACTION_NAME,
+
+       /**
+        * Convert item type to pointer to item name.
+        *
+        * Retrieves item name pointer from its type. The string itself is
+        * not copied; instead, a unique pointer to an internal static
+        * constant storage is written to @p dst.
+        *
+        * - @p src type:
+        *   @code (const void *)enum rte_flow_item_type @endcode
+        * - @p dst type:
+        *   @code const char ** @endcode
+        */
+       RTE_FLOW_CONV_OP_ITEM_NAME_PTR,
+
+       /**
+        * Convert action type to pointer to action name.
+        *
+        * Retrieves action name pointer from its type. The string itself is
+        * not copied; instead, a unique pointer to an internal static
+        * constant storage is written to @p dst.
+        *
+        * - @p src type:
+        *   @code (const void *)enum rte_flow_action_type @endcode
+        * - @p dst type:
+        *   @code const char ** @endcode
+        */
+       RTE_FLOW_CONV_OP_ACTION_NAME_PTR,
 };
 
 /**