Add a fallback callback to enum_name printf hook

If mapping the enum value failed, the callback can directly write
to the output stream to write the fallback value.

diff --git a/src/libstrongswan/enum.c b/src/libstrongswan/enum.c
index 6481f6f8283cf7ee4394af3a2d1cb83d63873ce6..31f2d09c666d8e9adea90eb7f9dfb66e78365605 100644 (file)
--- a/src/libstrongswan/enum.c
+++ b/src/libstrongswan/enum.c
@@ -78,6 +78,10 @@ int enum_printf_hook(printf_hook_data_t *data, printf_hook_spec_t *spec,
        name = enum_to_name(e, val);
        if (name == NULL)
        {
+               if (e->cb)
+               {
+                       return e->cb(data, 0, e, val);
+               }
                return print_in_hook(data, "(%d)", val);
        }
        else
@@ -108,6 +112,10 @@ int enum_dynamic_printf_hook(printf_hook_data_t *data, printf_hook_spec_t *spec,
        }
        if (name == NULL)
        {
+               if (e && e->cb)
+               {
+                       return e->cb(data, id, e, val);
+               }
                return print_in_hook(data, "(%d)", val);
        }
        else

diff --git a/src/libstrongswan/enum.h b/src/libstrongswan/enum.h
index f24e0328974eb6ec44ce5a6c083a53fb180f5374..69cf5a62b57cef9badd962ddc728b437d1eb6339 100644 (file)
--- a/src/libstrongswan/enum.h
+++ b/src/libstrongswan/enum.h
@@ -35,6 +35,21 @@ typedef struct enum_name_elem_t enum_name_elem_t;
  */
 typedef enum_name_t* (*enum_name_get_t)(int id);
 
+/**
+ * Fallback callback to call if enum could not be mapped to a string.
+ *
+ * This callback is invoked from within the printf hook. Use print_in_hook()
+ * with the supplied data to write to the output stream.
+ *
+ * @param data         printf hook data to pass to print_in_hook()
+ * @param id           index variable, as passed to enum_name_get function, or 0
+ * @param e                    enum name for which callback is invoked
+ * @param val          enum value to map
+ * @return                     number of characters written
+ */
+typedef int (*enum_name_cb_t)(printf_hook_data_t *data, int id, enum_name_t *e,
+                                                         int val);
+
 /**
  * Struct to store names for enums.
  *
@@ -70,6 +85,8 @@ typedef enum_name_t* (*enum_name_get_t)(int id);
 struct enum_name_t {
        /** first enum_name_elem_t in chain */
        enum_name_elem_t *elem;
+       /** callback function to invoke if enum string for value not found */
+       enum_name_cb_t cb;
 };
 
 struct enum_name_elem_t {
@@ -116,6 +133,17 @@ struct enum_name_elem_t {
        static enum_name_t name##head = { .elem = &name##prev }; \
        enum_name_t *name = &name##head
 
+/**
+ * Complete enum name list started with ENUM_BEGIN, with a fallback callback.
+ *
+ * @param name name of the enum_name list
+ * @param cbf  callback function if enum value could not be mapped
+ * @param prev enum value of the "last" defined in ENUM_BEGIN/previous ENUM_NEXT
+ */
+#define ENUM_END_CB(name, cbf, prev) \
+       static enum_name_t name##head = { .elem = &name##prev, .cb = cbf }; \
+       enum_name_t *name = &name##head
+
 /**
  * Define a enum name with only one range.
  *
@@ -130,6 +158,18 @@ struct enum_name_elem_t {
 #define ENUM(name, first, last, ...) \
        ENUM_BEGIN(name, first, last, __VA_ARGS__); ENUM_END(name, last)
 
+/**
+ * Define a enum name with only one range, but with a fallback callback.
+ *
+ * @param name name of the enum_name list
+ * @param cbf  callback function if enum value could not be mapped
+ * @param first        enum value of the first enum string
+ * @param last enum value of the last enum string
+ * @param ...  a list of strings
+ */
+#define ENUM_CB(name, cbf, first, last, ...) \
+       ENUM_BEGIN(name, first, last, __VA_ARGS__); ENUM_END_CB(name, cbf, last)
+
 /**
  * Convert a enum value to its string representation.
  *