This patch replaces the former prominent use of pointers by references
wherever feasible. This has the following benefits:
* The contract between caller and callee becomes more obvious. When
passing a reference, the contract says that the argument cannot be
a null pointer. The caller is responsible to ensure that. Therefore,
the use of reference eliminates the need to add defensive null-pointer
checks at the callee site, which sometimes merely exist to be on the
safe side. The bottom line is that the code becomes easier to follow.
* Reference members must be initialized via an object initializer,
which promotes a programming style that avoids intermediate object-
construction states. Within core, there are still a few pointers
as member variables left though. E.g., caused by the late association
of 'Platform_thread' objects with their 'Platform_pd' objects.
* If no pointers are present as member variables, we don't need to
manually provide declarations of a private copy constructor and
an assignment operator to avoid -Weffc++ errors "class ... has
pointer data members [-Werror=effc++]".
This patch also changes a few system bindings on NOVA and Fiasco.OC,
e.g., the return value of the global 'cap_map' accessor has become a
reference. Hence, the patch touches a few places outside of core.
Fixes#3135
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
Put the initialization of the cpu cores, setup of page-tables, enabling of
MMU and caches into a separate component that is only used to bootstrap
the kernel resp. core.
Ref #2092
base generic code:
* Remove unused verbosity code from mmio framework
* Remove escape sequence end heuristic from LOG
* replace Core_console with Core_log (no format specifiers)
* move test/printf to test/log
* remove `printf()` tests from the log test
* check for exact match of the log test output
base-fiasco:
* remove unused Fiasco::print_l4_threadid function
base-nova:
* remove unused hexdump utility from core
base-hw:
* remove unused Kernel::Thread::_print_* debug utilities
* always print resource summary of core during startup
* remove Kernel::Ipc_node::pd_label (not used anymore)
base*:
* Turn `printf`,`PWRN`, etc. calls into their log equivalents
Ref #1987Fix#2119
The sinfo function declared in sinfo_instance.h creates a static sinfo
object instance and returns a pointer to the caller.
- kernel timer and platform support to use sinfo() function to
instantiate sinfo object
- address and size of the base-hw RAM region via the sinfo API
- log_status() function in sinfo API
The platform-specific get_msi_params function returns MSI parameters for
a device identified by PCI config space address. The function returns
false if either the platform or the device does not support MSI mode of
operation.
Move Platform::setup_irq_mode function from x86 platform_support.cc to
x86_64 specific file. This will enable the upcoming x86_64_muen platform
to provide a separate implementation.
Move the _core_only_mmio_regions function to the
x86_64/platform_support.cc file. This is required to make it overridable
for other platforms deriving from x86.
Ehmry -
Sebastian Sumpf
Stefan Kalkowski
Martin Stein
Norman Feske
Alexander Boettcher
Adrian-Ken Rueegsegger
Reto Buerki