The 'File_system::Connection' already performs an on-demand session
upgrade should the server report an 'Out_of_caps' or 'Out_of_ram'
condition. So file-system clients are normally relieved from handling
those exceptions. However, the upgrade was limited to two attempts per
operation (which amounts to 16 KiB). When using the Rump VFS plugin in
the VFS server, this amount does not always suffice. So the exception is
reflected to the client. I observed this problem as a message "unhandled
error" printed by fs_rom. This patch removes the upgrade limit such that
a greedy file-system server becomes iteratively upgraded until it stops
arguing or the client's RAM is exhausted.
This patch reduces the number of exception types by facilitating
globally defined exceptions for common usage patterns shared by most
services. In particular, RPC functions that demand a session-resource
upgrade not longer reflect this condition via a session-specific
exception but via the 'Out_of_ram' or 'Out_of_caps' types.
Furthermore, the 'Parent::Service_denied', 'Parent::Unavailable',
'Root::Invalid_args', 'Root::Unavailable', 'Service::Invalid_args',
'Service::Unavailable', and 'Local_service::Factory::Denied' types have
been replaced by the single 'Service_denied' exception type defined in
'session/session.h'.
This consolidation eases the error handling (there are fewer exceptions
to handle), alleviates the need to convert exceptions along the
session-creation call chain, and avoids possible aliasing problems
(catching the wrong type with the same name but living in a different
scope).
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
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
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.
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
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
