diff options
Diffstat (limited to 'sql/udf_example.cc')
| -rw-r--r-- | sql/udf_example.cc | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/sql/udf_example.cc b/sql/udf_example.cc index ba056a9d2fd..6748be5a06f 100644 --- a/sql/udf_example.cc +++ b/sql/udf_example.cc @@ -56,7 +56,9 @@ ** ** Function 'myfunc_int' returns summary length of all its arguments. ** -** Function 'sequence' returns an sequence starting from a certain number +** Function 'sequence' returns an sequence starting from a certain number. +** +** Function 'myfunc_argument_name' returns name of argument. ** ** On the end is a couple of functions that converts hostnames to ip and ** vice versa. @@ -82,6 +84,7 @@ ** CREATE FUNCTION lookup RETURNS STRING SONAME "udf_example.so"; ** CREATE FUNCTION reverse_lookup RETURNS STRING SONAME "udf_example.so"; ** CREATE AGGREGATE FUNCTION avgcost RETURNS REAL SONAME "udf_example.so"; +** CREATE FUNCTION myfunc_argument_name RETURNS STRING SONAME "udf_example.so"; ** ** After this the functions will work exactly like native MySQL functions. ** Functions should be created only once. @@ -94,6 +97,7 @@ ** DROP FUNCTION lookup; ** DROP FUNCTION reverse_lookup; ** DROP FUNCTION avgcost; +** DROP FUNCTION myfunc_argument_name; ** ** The CREATE FUNCTION and DROP FUNCTION update the func@mysql table. All ** Active function will be reloaded on every restart of server @@ -984,4 +988,43 @@ avgcost( UDF_INIT* initid, UDF_ARGS* args, char* is_null, char* error ) return data->totalprice/double(data->totalquantity); } +extern "C" { +my_bool myfunc_argument_name_init(UDF_INIT *initid, UDF_ARGS *args, + char *message); +char *myfunc_argument_name(UDF_INIT *initid, UDF_ARGS *args, char *result, + unsigned long *length, char *null_value, + char *error); +} + +my_bool myfunc_argument_name_init(UDF_INIT *initid, UDF_ARGS *args, + char *message) +{ + if (args->arg_count != 1) + { + strmov(message,"myfunc_argument_name_init accepts only one argument"); + return 1; + } + initid->max_length= args->attribute_lengths[0]; + initid->maybe_null= 1; + initid->const_item= 1; + return 0; +} + +char *myfunc_argument_name(UDF_INIT *initid, UDF_ARGS *args, char *result, + unsigned long *length, char *null_value, + char *error) +{ + if (!args->attributes[0]) + { + null_value= 0; + return 0; + } + (*length)--; // space for ending \0 (for debugging purposes) + if (*length > args->attribute_lengths[0]) + *length= args->attribute_lengths[0]; + memcpy(result, args->attributes[0], *length); + result[*length]= 0; + return result; +} + #endif /* HAVE_DLOPEN */ |