We usually don't read the whole file into memory, so the probing interface will
also allow for the specification of boundaries that we should be use for
reading.
The sstable needs to be informed - usually by the schema - of how many columns
the partition key is composed of - 1 for simple keys, more than one, for
composites.
Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Because we're expected to go to those files many times, it doesn't make sense
to keep opening them. Upon sstable load, we will open those files and then move
the reference to the sstable main structure. From this point on, we can just seek
to the position we want.
Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
So it represents all kinds of mismatches. Not only buf < expected.
It will be useful in the index parsing code.
Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Right now we will always move the file to create a shared pointer from it.
However, there are situations in which we don't really want to move it, because
it will be still used elsewhere.
One example is the index and data readers, where we will store a file object to
avoid opening the file all the time. In such situation, we can pass a shared
pointer that is already constructed to the file_input_stream.
The alternative to that would have been to store the file_input_stream itself.
That would, however, require us to export that in some header. It's best to
keep it private. Since we will already deal with a shared pointer anyway, it is
best to provide this option.
Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Includes adaptation by Nadav for the removal of file_input_stream:
sstables.cc used file_input_stream, which we replaced by the new
make_file_input_stream. We also couldn't make sstables.cc read either
a file_input_stream or the planned compressed_file_input_stream.
So in this patch we implement an API similar to the old "file_input_stream"
based on the new make_file_input_stream. file_input_stream now has a parent
class "random_access_reader", preparing for a future patch to support both
file_input_stream and compressed_file_input_stream in the same code - by making
all the parsers take a random_access_reader reference instead of file_input_stream.
Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
boost::split() expects either a NUL terminated string or a proper container.
We give it neither.
Fix by wrapping the buffer in a string_view, which tells split() what size
the string is.
This is a parser for the sstable files based on template recursion.
With this, one can easily extend it to parse any complex data structure
by writing
parse(in, struct.a, struct.b ... );
This patch contains the most basic types used during parsing as building
blocks.
Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
This represents an sstable with its multiple in-disk file. We don't yet
read any of them, though.
Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Reviewed-by: Nadav Har'El <nyh@cloudius-systems.com>
