PHP: Add custom capability_type to soliloquy.

add-capabilities-to-role.php

<?php

/**
 * Add custom capabilities to role
 * 
 * @param string $role Role to add capabilities.
 * @param array $caps Custom capabilities.
 */
function gs_add_caps_to_role( $role, $caps ) {
    /** Convert object to an array */
    if ( is_object( $caps ) )
        $caps = json_decode( json_encode( $caps ), true );
    
    /** Make sure we have an array, bail otherwise */
    if ( !is_array( $caps ) ) return;
    
    /** Get specified role object */
    $role = get_role( $role );
    
    /** Cycle through caps & add to role */
    foreach( array_values( $caps ) as $cap )
        $role->add_cap( $cap ); 
}

soliloquy-capabilities.php

<?php

add_filter( 'tgmsp_post_type_args', 'gs_tgmsp_post_type_args' );
/**
 * Filters Soliloquy post type registration parameters.
 * 
 * @param array $args Soliloquy post type registration args.
 * @return array $args Modified soliloquy post type registration args.
 */
function gs_tgmsp_post_type_args( $args ) {
    $args['capability_type'] = 'soliloquy';
    return $args;
}

add_action( 'registered_post_type', 'gs_tgmsp_add_caps_to_admin', 10, 2 );
/**
 * Add capabilities to soliloquy custom post type
 * 
 * @param string $post_type Post type.
 * @param array $args Original post type registration args.
 */
function gs_tgmsp_add_caps_to_admin( $post_type, $args ) {
    /** Make sure we have the correct post type */
    if ( 'soliloquy' !== $post_type ) return;
    
    /** Get post type object to get capabilities */
    $pt = get_post_type_object( $post_type );
    
    /** Add capabilities to administrator */
    gs_add_caps_to_role( 'administrator', $pt->cap );
}

soliloquy-capabilitiesalt.php

<?php

add_action( 'registered_post_type', 'gs_tgmsp_add_caps_to_admin', 10, 2 );
/**
 * Add capabilities to soliloquy custom post type
 * 
 * @param string $post_type Post type.
 * @param array $args Original post type registration args.
 */
function gs_tgmsp_add_caps_to_admin( $post_type, $args ) {
    /** Make sure we have the correct post type */
    if ( 'soliloquy' !== $post_type ) return;
    
    /** Get global post type object */
    global $wp_post_types;
    
    /** Add capabilities to administrator */
    gs_add_caps_to_role( 'administrator', $wp_post_types[ $post_type ]->cap );
}

soliloquy-capabilitiesmultiple.php

<?php

add_action( 'registered_post_type', 'gs_tgmsp_add_caps_to_admin', 10, 2 );
/**
 * Add capabilities to soliloquy custom post type
 * 
 * @param string $post_type Post type.
 * @param array $args Original post type registration args.
 */
function gs_tgmsp_add_caps_to_admin( $post_type, $args ) {
    /** Make sure we have the correct post type */
    if ( 'soliloquy' !== $post_type ) return;
    
    /** Get post type object to get capabilities */
    $pt = get_post_type_object( $post_type );
    
    /** Add capabilities to roles */
    foreach( array( 'administrator', 'editor', ) as $role )
      gs_add_caps_to_role( $role, $pt->cap );
}

A full tutorial explaining how to limit users to Soliloquy and how to add a custom capability to Soliloquy can be found at http://wpsmith.net/2013/plugins/limit-users-to-soliloquy-how-to-add-a-custom-capability-to-soliloquy/ (Shortlink: http://wpsmith.net/?p=22740).