问使用XCB的怪异递归行为

EN

#include <stdio.h>
#include <xcb/xcb.h>

int i = 0;

int connect(xcb_connection_t** conn) {
    xcb_connection_t* try_conn = xcb_connect(NULL, NULL);
    int status = 0;
    int conn_status = xcb_connection_has_error(try_conn);
    if (conn_status != 0) {
        i = i + 1;
        switch (conn_status) {
            case XCB_CONN_ERROR:
                printf("Error connecting to the X Server, try %d\n", i);
                break;
            case XCB_CONN_CLOSED_EXT_NOTSUPPORTED:
                printf("Connection closed, extension not supported\n");
                break;
            case XCB_CONN_CLOSED_MEM_INSUFFICIENT:
                printf("Connection closed, memory insufficient\n");
                break;
            case XCB_CONN_CLOSED_REQ_LEN_EXCEED:
                printf("Connection closed, required length exceeded\n");
                break;
            case XCB_CONN_CLOSED_PARSE_ERR:
                printf("Connection closed, parse error\n");
                break;
            case XCB_CONN_CLOSED_INVALID_SCREEN:
                printf("Connection closed, invalid screen\n");
                break;
            default:
                printf("Connection failed with unknown cause\n");
                break;
        }

        status = 1;
    } else {
        *conn = try_conn;
        status = 0;
    }

    return status;
}

int main() {
    xcb_connection_t* conn = NULL;
    if (connect(&conn) != 0) {
        printf("Error connecting to the X Server\n");
        return -1;
    }

    return 0;
}