Commit Graph

14 Commits

Author SHA1 Message Date
Norman Feske
405a9d2144 Refinements for updated "Genode Foundations" book
- Improve API descriptions
- Remove obsolete Xml_node::value method (fixes #3323)
- Follow coding style 'const char' -> 'char const'
- Avoid '>>' when nesting templates (limitation of parse_cxx)
2019-05-27 14:52:53 +02:00
Norman Feske
5ed5fddb7c base/os: remove deprecated APIs
This commit removes APIs that were previously marked as deprecated. This
change has the following implications:

- The use of the global 'env()' accessor is not possible anymore.
- Boolean accessor methods are no longer prefixed with 'is_'. E.g.,
  instead of 'is_valid()', use 'valid()'.
- The last traces of 'Ram_session' are gone now. The 'Env::ram()'
  accessor returns the 'Ram_allocator' interface, which is a subset of
  the 'Pd_session' interface.
- All connection constructors need the 'Env' as argument.
- The 'Reporter' constructor needs an 'Env' argument now because the
  reporter creates a report connection.
- The old overload 'Child_policy::resolve_session_request' that returned
  a 'Service' does not exist anymore.
- The base/printf.h header has been removed, use base/log.h instead.
- The old notion of 'Signal_dispatcher' is gone. Use 'Signal_handler'.
- Transitional headers like os/server.h, cap_session/,
  volatile_object.h, os/attached*_dataspace.h, signal_rpc_dispatcher.h
  have been removed.
- The distinction between 'Thread_state' and 'Thread_state_base' does
  not exist anymore.
- The header cpu_thread/capability.h along with the type definition of
  'Cpu_thread_capability' has been removed. Use the type
  'Thread_capability' define in cpu_session/cpu_session.h instead.
- Several XML utilities (i.e., at os/include/decorator) could be removed
  because their functionality is nowadays covered by util/xml_node.h.
- The 'os/ram_session_guard.h' has been removed.
  Use 'Constrained_ram_allocator' provided by base/ram_allocator.h instead.

Issue #1987
2019-02-26 14:44:15 +01:00
Norman Feske
eba9c15746 Follow practices suggested by "Effective C++"
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:

* A class with virtual functions can no longer publicly inherit base
  classed without a vtable. The inherited object may either be moved
  to a member variable, or inherited privately. The latter would be
  used for classes that inherit 'List::Element' or 'Avl_node'. In order
  to enable the 'List' and 'Avl_tree' to access the meta data, the
  'List' must become a friend.

* Instead of adding a virtual destructor to abstract base classes,
  we inherit the new 'Interface' class, which contains a virtual
  destructor. This way, single-line abstract base classes can stay
  as compact as they are now. The 'Interface' utility resides in
  base/include/util/interface.h.

* With the new warnings enabled, all member variables must be explicitly
  initialized. Basic types may be initialized with '='. All other types
  are initialized with braces '{ ... }' or as class initializers. If
  basic types and non-basic types appear in a row, it is nice to only
  use the brace syntax (also for basic types) and align the braces.

* If a class contains pointers as members, it must now also provide a
  copy constructor and assignment operator. In the most cases, one
  would make them private, effectively disallowing the objects to be
  copied. Unfortunately, this warning cannot be fixed be inheriting
  our existing 'Noncopyable' class (the compiler fails to detect that
  the inheriting class cannot be copied and still gives the error).
  For now, we have to manually add declarations for both the copy
  constructor and assignment operator as private class members. Those
  declarations should be prepended with a comment like this:

        /*
         * Noncopyable
         */
        Thread(Thread const &);
        Thread &operator = (Thread const &);

  In the future, we should revisit these places and try to replace
  the pointers with references. In the presence of at least one
  reference member, the compiler would no longer implicitly generate
  a copy constructor. So we could remove the manual declaration.

Issue #465
2018-01-17 12:14:35 +01:00
Norman Feske
adb26b5216 API documentation refinements 2017-05-31 13:16:21 +02:00
Norman Feske
c1b981ede4 Annotate session interfaces with CAP_QUOTA
The new 'CAP_QUOTA' enum value denotes the capability quota to be
transferred from the client to the server at session-creation time.

Issue #2398
2017-05-31 13:16:04 +02:00
Norman Feske
29b8d609c9 Adjust file headers to refer to the AGPLv3 2017-02-28 12:59:29 +01:00
Norman Feske
9cba459958 base: remove Child::heap
This patch improves the accounting for the backing store of
session-state meta data. Originally, the session state used to be
allocated by a child-local heap partition fed from the child's RAM
session. However, whereas this approach was somehow practical from a
runtime's (parent's) point of view, the child component could not count
on the quota in its own RAM session. I.e., if the Child::heap grew at
the parent side, the child's RAM session would magically diminish. This
caused two problems. First, it violates assumptions of components like
init that carefully manage their RAM resources (and giving most of them
away their children). Second, if a child transfers most of its RAM
session quota to another RAM session (like init does), the child's RAM
session may actually not allow the parent's heap to grow, which is a
very difficult error condition to deal with.

In the new version, there is no Child::heap anymore. Instead, session
states are allocated from the runtime's RAM session. In order to let
children pay for these costs, the parent withdraws the local session
costs from the session quota donated from the child when the child
initiates a new session. Hence, in principle, all components on the
route of the session request take a small bite from the session quota to
pay for their local book keeping

Consequently, the session quota that ends up at the server may become
depleted more or less, depending on the route. In the case where the
remaining quota is insufficient for the server, the server responds with
'QUOTA_EXCEEDED'. Since this behavior must generally be expected, this
patch equips the client-side 'Env::session' implementation with the
ability to re-issue session requests with successively growing quota
donations.

For several of core's services (ROM, IO_MEM, IRQ), the default session
quota has now increased by 2 KiB, which should suffice for session
requests to up to 3 hops as is the common case for most run scripts. For
longer routes, the retry mechanism as described above comes into effect.
For the time being, we give a warning whenever the server-side quota
check triggers the retry mechanism. The warning may eventually be
removed at a later stage.
2017-02-28 12:59:23 +01:00
Norman Feske
a7f40b24ca Warn about the use of deprecated env() function
This patch enables warnings if one of the deprecate functions that rely
in the implicit use of the global Genode::env() accessor are called.

For the time being, some places within the base framework continue
to rely on the global function while omitting the warning by calling
'env_deprecated' instead of 'env'.

Issue #1987
2017-01-13 13:07:13 +01:00
Norman Feske
e370e08e01 Define Genode::size_t as unsigned long
Fixes #2105
2016-10-21 12:39:29 +02:00
Norman Feske
97a41394b4 Documentation changes on account of the book
This patch removes the outdates doc/architecture.txt since the
topics are covered by the book. We keep repos/os/doc/init.txt
because it contains a few details not present in the book (yet).
The patch streamlines the terminology a bit. Furthermore, it
slightly adjusts a few source-code comments to improve the book's
functional specification chapter.
2016-05-26 15:54:16 +02:00
Norman Feske
a7b3072cc2 Pass Env & as first argument to connection objects
This patch supplements each existing connection type with an new
constructor that is meant to replace the original one. The new
one takes a reference to the component's environment as argument and
thereby does not rely on the presence of the globally accessible
'env()' interface.

The original constructors are marked as deprecated. Once we have
completely abolished the use of the global 'env()', we will remove them.

Fixes #1960
2016-05-23 15:52:37 +02:00
Norman Feske
8d797105b3 Move Attach_*dataspace utils from os to base
Fixes #1958
2016-05-23 15:52:36 +02:00
Norman Feske
e8336acafc base,os: Coding-style unification
Fixes #1432
2015-03-13 12:17:23 +01:00
Norman Feske
ca971bbfd8 Move repositories to 'repos/' subdirectory
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.

Issue #1082
2014-05-14 16:08:00 +02:00