/**
* rasqal_new_variable_from_variable:
* @v: #rasqal_variable to copy
*
* Copy Constructor - Create a new Rasqal variable from an existing one
*
* This does a deep copy of all variable fields
*
* Return value: a new #rasqal_variable or NULL on failure.
**/
rasqal_variable*
rasqal_new_variable_from_variable(rasqal_variable* v)
{
rasqal_variable* new_v;
size_t name_len;
unsigned char *new_name;
new_v = (rasqal_variable*)RASQAL_CALLOC(rasqal_variable, 1,
sizeof(rasqal_variable));
if(!new_v)
return NULL;
name_len = strlen((const char*)v->name);
new_name = (unsigned char*)RASQAL_MALLOC(cstring, name_len+1);
if(!new_name) {
RASQAL_FREE(rasqal_variable, new_v);
return NULL;
}
memcpy(new_name, v->name, name_len+1);
new_v->vars_table = v->vars_table;
new_v->name= new_name;
new_v->value= rasqal_new_literal_from_literal(v->value);
new_v->offset= v->offset;
new_v->type= v->type;
new_v->expression= rasqal_new_expression_from_expression(v->expression);
return new_v;
}
/**
* rasqal_new_join_rowsource:
* @world: world object
* @query: query object
* @left: input left (first) rowsource
* @right: input right (second) rowsource
* @join_type: join type
* @expr: join expression to filter result rows
*
* INTERNAL - create a new JOIN over two rowsources
*
* This uses the number of variables in @vt to set the rowsource size
* (order size is always 0) and then checks that all the rows in the
* sequence are the same. If not, construction fails and NULL is
* returned.
*
* The @left and @right rowsources become owned by the rowsource.
*
* Return value: new rowsource or NULL on failure
*/
rasqal_rowsource*
rasqal_new_join_rowsource(rasqal_world *world,
rasqal_query* query,
rasqal_rowsource* left,
rasqal_rowsource* right,
rasqal_join_type join_type,
rasqal_expression *expr)
{
rasqal_join_rowsource_context* con;
int flags = 0;
if(!world || !query || !left || !right)
goto fail;
/* only left outer join and cross join supported */
if(join_type != RASQAL_JOIN_TYPE_LEFT &&
join_type != RASQAL_JOIN_TYPE_NATURAL)
goto fail;
con = RASQAL_CALLOC(rasqal_join_rowsource_context*, 1, sizeof(*con));
if(!con)
goto fail;
con->left = left;
con->right = right;
con->join_type = join_type;
con->expr = rasqal_new_expression_from_expression(expr);
return rasqal_new_rowsource_from_handler(world, query,
con,
&rasqal_join_rowsource_handler,
query->vars_table,
flags);
fail:
if(left)
rasqal_free_rowsource(left);
if(right)
rasqal_free_rowsource(right);
return NULL;
}
rasqal_rowsource*
rasqal_new_aggregation_rowsource(rasqal_world *world, rasqal_query* query,
rasqal_rowsource* rowsource,
raptor_sequence* exprs_seq,
raptor_sequence* vars_seq)
{
rasqal_aggregation_rowsource_context* con;
int flags = 0;
int size;
int i;
if(!world || !query || !rowsource || !exprs_seq || !vars_seq)
goto fail;
exprs_seq = rasqal_expression_copy_expression_sequence(exprs_seq);
vars_seq = rasqal_variable_copy_variable_sequence(vars_seq);
size = raptor_sequence_size(exprs_seq);
if(size != raptor_sequence_size(vars_seq)) {
RASQAL_DEBUG3("expressions sequence size %d does not match vars sequence size %d\n", size, raptor_sequence_size(vars_seq));
goto fail;
}
con = (rasqal_aggregation_rowsource_context*)RASQAL_CALLOC(rasqal_aggregation_rowsource_context, 1, sizeof(*con));
if(!con)
goto fail;
con->rowsource = rowsource;
con->exprs_seq = exprs_seq;
con->vars_seq = vars_seq;
/* allocate per-expr data */
con->expr_count = size;
con->expr_data = (rasqal_agg_expr_data*)RASQAL_CALLOC(rasqal_agg_expr_data,
sizeof(rasqal_agg_expr_data),
size);
if(!con->expr_data)
goto fail;
/* Initialise per-expr data */
for(i = 0; i < size; i++) {
rasqal_expression* expr = (rasqal_expression *)raptor_sequence_get_at(exprs_seq, i);
rasqal_variable* variable = (rasqal_variable*)raptor_sequence_get_at(vars_seq, i);
rasqal_agg_expr_data* expr_data = &con->expr_data[i];
expr_data->expr = rasqal_new_expression_from_expression(expr);
expr_data->variable = variable;
/* Prepare expression arguments sequence in per-expr data */
if(expr->args) {
/* list of #rasqal_expression arguments already in expr
* #RASQAL_EXPR_FUNCTION and #RASQAL_EXPR_GROUP_CONCAT
*/
expr_data->exprs_seq = rasqal_expression_copy_expression_sequence(expr->args);
} else {
/* single argument */
expr_data->exprs_seq = raptor_new_sequence((raptor_data_free_handler)rasqal_free_expression,
(raptor_data_print_handler)rasqal_expression_print);
raptor_sequence_push(expr_data->exprs_seq,
rasqal_new_expression_from_expression(expr->arg1));
}
}
return rasqal_new_rowsource_from_handler(world, query,
con,
&rasqal_aggregation_rowsource_handler,
query->vars_table,
flags);
fail:
if(rowsource)
rasqal_free_rowsource(rowsource);
if(exprs_seq)
raptor_free_sequence(exprs_seq);
if(vars_seq)
raptor_free_sequence(vars_seq);
return NULL;
}