For the purpose of scylla-gdb.py command "scylla
active-sstables". Before the patch, readers were located by scanning
the heap for live objects with vtable pointers corresponding to
readers. It was observed that the test scylla_gdb/test_misc.py::test_active_sstables started failing like this:
gdb.error: Error occurred in Python: Cannot access memory at address 0x300000000000000
This could be explained by there being a live object on the heap which
used to be a reader but now is a different object, and the _sst field
contains some other data which is not a pointer.
To fix, track readers explicitly in a linked list so that the gdb
script can reliably walk readers.
Fixes#18618.
since we do not rely on FMT_DEPRECATED_OSTREAM to define the
fmt::formatter for us anymore, let's stop defining `FMT_DEPRECATED_OSTREAM`.
in this change,
* utils: drop the range formatters in to_string.hh and to_string.c, as
we don't use them anymore. and the tests for them in
test/boost/string_format_test.cc are removed accordingly.
* utils: use fmt to print chunk_vector and small_vector. as
we are not able to print the elements using operator<< anymore
after switching to {fmt} formatters.
* test/boost: specialize fmt::details::is_std_string_like<bytes>
due to a bug in {fmt} v9, {fmt} fails to format a range whose
element type is `basic_sstring<uint8_t>`, as it considers it
as a string-like type, but `basic_sstring<uint8_t>`'s char type
is signed char, not char. this issue does not exist in {fmt} v10,
so, in this change, we add a workaround to explicitly specialize
the type trait to assure that {fmt} format this type using its
`fmt::formatter` specialization instead of trying to format it
as a string. also, {fmt}'s generic ranges formatter calls the
pair formatter's `set_brackets()` and `set_separator()` methods
when printing the range, but operator<< based formatter does not
provide these method, we have to include this change in the change
switching to {fmt}, otherwise the change specializing
`fmt::details::is_std_string_like<bytes>` won't compile.
* test/boost: in tests, we use `BOOST_REQUIRE_EQUAL()` and its friends
for comparing values. but without the operator<< based formatters,
Boost.Test would not be able to print them. after removing
the homebrew formatters, we need to use the generic
`boost_test_print_type()` helper to do this job. so we are
including `test_utils.hh` in tests so that we can print
the formattable types.
* treewide: add "#include "utils/to_string.hh" where
`fmt::formatter<optional<>>` is used.
* configure.py: do not define FMT_DEPRECATED_OSTREAM
* cmake: do not define FMT_DEPRECATED_OSTREAM
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
Needed before converting the mx reader to flat_mutation_reader_v2
because now it and the k_l reader cannot share the reader
implementation. They derive from different reader impl bases and push
different fragment types.
The entire sstable cell value is currently stored in a single
temporary_buffer. Cells may be very large, so to avoid large
contiguous allocations, the buffer is changed to
a fragmented_temporary_buffer.
Fixes#7457Fixes#6376
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
Move stuff contained therein to `sstable_mutation_reader.{hh,cc}` which
will serve as the collection point of utility stuff needed by all reader
implementations.
The sstable reader currently knows the definition of all the different
consumers and contexts. But it doesn't really need to, as it is a
template. Exploit this and prepare for a organization scheme where the
consumers and contexts live hidden in a cc file which includes and
instantiates the sstable reader template. As a first step expose
`sstable_mutation_reader` in a header.
