genode/repos/os/include/nic/root.h
Norman Feske 17c79a9e23 base: avoid use of deprecated base/printf.h
Besides adapting the components to the use of base/log.h, the patch
cleans up a few base headers, i.e., it removes unused includes from
root/component.h, specifically base/heap.h and
ram_session/ram_session.h. Hence, components that relied on the implicit
inclusion of those headers have to manually include those headers now.

While adjusting the log messages, I repeatedly stumbled over the problem
that printing char * arguments is ambiguous. It is unclear whether to
print the argument as pointer or null-terminated string. To overcome
this problem, the patch introduces a new type 'Cstring' that allows the
caller to express that the argument should be handled as null-terminated
string. As a nice side effect, with this type in place, the optional len
argument of the 'String' class could be removed. Instead of supplying a
pair of (char const *, size_t), the constructor accepts a 'Cstring'.
This, in turn, clears the way let the 'String' constructor use the new
output mechanism to assemble a string from multiple arguments (and
thereby getting rid of snprintf within Genode in the near future).

To enforce the explicit resolution of the char * ambiguity, the 'char *'
overload of the 'print' function is marked as deleted.

Issue #1987
2016-08-29 17:27:10 +02:00

76 lines
2.1 KiB
C++

/**
* \brief Simple single client NIC Root
* \author Sebastian Sumpf
* \date 2015-06-23
*/
/*
* Copyright (C) 2015 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__NIC__ROOT_H_
#define _INCLUDE__NIC__ROOT_H_
#include <nic/component.h>
#include <root/component.h>
namespace Nic {
template <class SESSION_COMPONENT> class Root;
};
template <class SESSION_COMPONENT>
class Nic::Root : public Genode::Root_component<SESSION_COMPONENT,
Genode::Single_client>
{
private:
Server::Entrypoint &_ep;
protected:
SESSION_COMPONENT *_create_session(const char *args)
{
using namespace Genode;
size_t ram_quota = Arg_string::find_arg(args, "ram_quota" ).ulong_value(0);
size_t tx_buf_size = Arg_string::find_arg(args, "tx_buf_size").ulong_value(0);
size_t rx_buf_size = Arg_string::find_arg(args, "rx_buf_size").ulong_value(0);
/* deplete ram quota by the memory needed for the session structure */
size_t session_size = max(4096UL, (unsigned long)sizeof(SESSION_COMPONENT));
if (ram_quota < session_size)
throw Genode::Root::Quota_exceeded();
/*
* Check if donated ram quota suffices for both communication
* buffers and check for overflow
*/
if (tx_buf_size + rx_buf_size < tx_buf_size ||
tx_buf_size + rx_buf_size > ram_quota - session_size) {
Genode::error("insufficient 'ram_quota', got ", ram_quota, ", "
"need ", tx_buf_size + rx_buf_size + session_size);
throw Genode::Root::Quota_exceeded();
}
return new (Root::md_alloc())
SESSION_COMPONENT(tx_buf_size, rx_buf_size,
*env()->heap(),
*env()->ram_session(),
_ep);
}
public:
Root(Server::Entrypoint &ep, Genode::Allocator &md_alloc)
: Genode::Root_component<SESSION_COMPONENT, Genode::Single_client>(&ep.rpc_ep(), &md_alloc),
_ep(ep)
{ }
};
#endif /* _INCLUDE__NIC__ROOT_H_ */