How to return array of C ++ objects from PHP extension
I need my PHP extension to return an array of objects, but I can't figure out how.
I have an object Graph
written in C ++. Graph.getNodes()
returns a std::map<int, Node*>
. Here's the code I have:
struct node_object {
zend_object std;
Node * node;
};
zend_class_entry * node_ce;
then
PHP_METHOD (Graph, getNodes)
{
Graph * graph;
GET_GRAPH (graph, obj) // a macro I wrote to populate graph
node_object * n;
zval * node_zval;
if (obj == NULL) {
RETURN_NULL ();
}
if (object_init_ex (node_zval, node_ce)! = SUCCESS) {
RETURN_NULL ();
}
std :: map nodes = graph-> getNodes ();
array_init (return_value);
for (std :: map :: iterator i = nodes.begin (); i! = nodes.end (); ++ i) {
php_printf ("X");
n = (node_object *) zend_object_store_get_object (node_zval TSRMLS_CC);
n-> node = i-> second;
add_index_zval (return_value, i-> first, node_zval);
}
php_printf ("]");
}
When I run php -r '$g = new Graph(); $g->getNodes();'
I get the output
XX]Segmentation fault
means the getNodes () function successfully completes the loop on my 2-node list, returns and then segfaults. What am I doing wrong?
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I just needed MAKE_STD_ZVAL (node_zval). The second problem with this code was that I was reusing that zval pointer, thus overwriting every previous zval and ending up with an array full of the same object. To fix this, I initialize node_zval for every loop. Here's the last code:
PHP_METHOD (Graph, getNodes)
{
Graph * graph;
GET_GRAPH (graph, obj) // a macro I wrote to populate graph
node_object * n;
zval * node_zval;
if (obj == NULL) {
RETURN_NULL ();
}
std :: map nodes = graph-> getNodes ();
array_init (return_value);
for (std :: map :: iterator i = nodes.begin (); i! = nodes.end (); ++ i) {
MAKE_STD_ZVAL (node_zval);
if (object_init_ex (node_zval, node_ce)! = SUCCESS) {
RETURN_NULL ();
}
n = (node_object *) zend_object_store_get_object (node_zval TSRMLS_CC);
n-> node = i-> second;
add_index_zval (return_value, i-> first, node_zval);
}
}
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