Refactor the graphical terminal server to internally represent
characters as 16-bit codepoints and handle the duplex terminal stream as
UTF-8.
- Make the Codepoint class printable to the Output interface
- Decode data received at the Terminal session from UTF-8 to a 16-bit
character
- Pass 16-bit characters through terminal decoder and char-cell arrays
- Send Unicode through terminal session in a burst of UTF-8 bytes
Fix#3148
This patch adds a 'Color::print' method as counterpart to the 'ascii_to'
function. If the color is opaque (alpha is 255), its output has the form
"#rrggbb". If the color has a distinct alpha value, the output has the
form "#rrggbbaa". The new version of the 'ascii_to' overload for 'Color'
is able to deal with both forms.
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
Since the dynamic linker depends on the XML utils and we plan to replace
the ancient 'Arg_string' with XML, it is time to move the 'Xml_node' and
'Xml_generator' to base/include.
This overload of the value member eases the retrieval of Genode::String
objects from XML attributes. So we won't need to deal with C-style
character buffers anymore.
By appending a newline to the generated XML data, we prevent the output
from messing with the command prompt when using 'cat' on a shell.
Futhermore, when using line-buffered output, the trailing newline
ensures that the output gets gets properly flushed.
When calling 'sub_node' on a node with no sub nodes, the Xml_node would
interpret the characters after the current node while searching for sub
nodes. The patch adds a sanity check that lets the 'sub_node' function
throw an exception when called on a node with no sub nodes.
This patch makes the handling of constructor arguments consistent among
the Volatile_object and Lazy_volatile_object classes. Arguments are
always forwarded. Otherwise, passing a reference as argument would result
in an unwanted copy of the passed object.
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
