libevent: uninitialized structure pointer

Question

I have struct pointer in code

struct evkeyvalq *headers;

now I give call to a function which would fill some information in the structure.

evhttp_parse_query(uri, headers)

I get segmentation fault at this line. what would be the correct way to doing this. Thanks

Answer 1

You need to allocate some memory for your struct evkeyvalq. As your code is now, you pass an uninitialized pointer into evhttp_parse_query() , and there is no way for evhttp_parse_query() to operate properly.

Allocate the struct on the stack:

struct evkeyvalq headers;
evhttp_parse_query(uri, &headers);

Or use dynamically allocated memory:

struct evkeyvalq *headers = malloc(sizeof *headers);
if(headers != NULL) {
    evhttp_parse_query(uri, headers);
}