mirror of
https://github.com/genodelabs/genode.git
synced 2024-12-20 06:07:59 +00:00
141 lines
3.7 KiB
C++
141 lines
3.7 KiB
C++
/*
|
|
* \brief Utility for handling child configuration
|
|
* \author Norman Feske
|
|
* \date 2008-03-22
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2008-2013 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU General Public License version 2.
|
|
*/
|
|
|
|
#ifndef _INCLUDE__INIT__CHILD_CONFIG_H_
|
|
#define _INCLUDE__INIT__CHILD_CONFIG_H_
|
|
|
|
#include <base/env.h>
|
|
#include <base/printf.h>
|
|
#include <util/xml_node.h>
|
|
#include <rom_session/connection.h>
|
|
#include <ram_session/client.h>
|
|
|
|
namespace Init { class Child_config; }
|
|
|
|
|
|
class Init::Child_config
|
|
{
|
|
private:
|
|
|
|
enum { CONFIGFILE_NAME_LEN = 64 };
|
|
char _filename[CONFIGFILE_NAME_LEN];
|
|
|
|
Genode::Ram_session_capability _ram_session_cap;
|
|
Genode::Ram_dataspace_capability _config_ram_ds;
|
|
|
|
public:
|
|
|
|
/**
|
|
* Constructor
|
|
*
|
|
* The provided RAM session is used to obtain a dataspace for
|
|
* holding the copy of the child's configuration data unless the
|
|
* configuration is supplied via a config file. Normally, the
|
|
* child's RAM session should be used to account the consumed RAM
|
|
* quota to the child.
|
|
*/
|
|
Child_config(Genode::Ram_session_capability ram_session,
|
|
Genode::Xml_node start_node)
|
|
: _ram_session_cap(ram_session)
|
|
{
|
|
using namespace Genode;
|
|
|
|
/*
|
|
* If the start node contains a 'filename' entry, we only keep
|
|
* the information about the file name.
|
|
*/
|
|
_filename[0] = 0;
|
|
try {
|
|
Xml_node configfile_node = start_node.sub_node("configfile");
|
|
configfile_node.attribute("name")
|
|
.value(_filename, sizeof(_filename));
|
|
|
|
return;
|
|
} catch (...) { }
|
|
|
|
/*
|
|
* If the start node contains a 'config' entry, we copy this
|
|
* entry into a fresh dataspace to be provided to our child.
|
|
*/
|
|
Ram_session_client rsc(_ram_session_cap);
|
|
try {
|
|
Xml_node config_node = start_node.sub_node("config");
|
|
|
|
const char *config = config_node.addr();
|
|
Genode::size_t config_size = config_node.size();
|
|
|
|
if (!config || !config_size) return;
|
|
|
|
/*
|
|
* Allocate RAM dataspace that is big enough to
|
|
* hold the configuration and the null termination.
|
|
*/
|
|
_config_ram_ds = rsc.alloc(config_size + 1);
|
|
|
|
/*
|
|
* Make dataspace locally accessible, copy
|
|
* configuration into the dataspace, and append
|
|
* a string-terminating zero.
|
|
*/
|
|
void *addr = env()->rm_session()->attach(_config_ram_ds);
|
|
|
|
Genode::memcpy(addr, config, config_size);
|
|
static_cast<char *>(addr)[config_size] = 0;
|
|
env()->rm_session()->detach(addr);
|
|
|
|
} catch (Rm_session::Attach_failed) {
|
|
rsc.free(_config_ram_ds);
|
|
return;
|
|
} catch (Ram_session::Alloc_failed) {
|
|
return;
|
|
} catch (Xml_node::Nonexistent_sub_node) { }
|
|
}
|
|
|
|
/**
|
|
* Destructor
|
|
*/
|
|
~Child_config()
|
|
{
|
|
using namespace Genode;
|
|
|
|
/*
|
|
* The configuration data is either provided as a ROM session
|
|
* (holding a complete configfile) or as a RAM dataspace
|
|
* holding a copy of the start node's config entry. In the
|
|
* latter case, the child's configuration resides in a
|
|
* shadow copy kept in '_config_ram_ds'.
|
|
*/
|
|
if (_config_ram_ds.valid())
|
|
Ram_session_client(_ram_session_cap).free(_config_ram_ds);
|
|
}
|
|
|
|
/**
|
|
* Return file name if configuration comes from a file
|
|
*
|
|
* If the configuration is provided inline, the function returns 0.
|
|
*/
|
|
char const *filename() const {
|
|
return _filename[0] != 0 ? _filename : 0; }
|
|
|
|
/**
|
|
* Request dataspace holding the start node's configuration data
|
|
*
|
|
* This function returns a valid dataspace only when using an
|
|
* inline configuration (if 'filename()' returns 0).
|
|
*/
|
|
Genode::Dataspace_capability dataspace() {
|
|
return Genode::Dataspace_capability(_config_ram_ds); }
|
|
};
|
|
|
|
#endif /* _INCLUDE__INIT__CHILD_CONFIG_H_ */
|