in in {fmt} before v10, it provides the specialization of `fmt::formatter<..>`
for `std::string_view` as well as the specialization of `fmt::formatter<..>`
for `fmt::string_view` which is an implementation builtin in {fmt} for
compatibility of pre-C++17. and this type is used even if the code is
compiled with C++ stadandard greater or equal to C++17. also, before v10,
the `fmt::formatter<std::string_view>::format()` is defined so it accepts
`std::string_view`. after v10, `fmt::formatter<std::string_view>` still
exists, but it is now defined using `format_as()` machinery, so it's
`format()` method does not actually accept `std::string_view`, it
accepts `fmt::string_view`, as the former can be converted to
`fmt::string_view`.
this is why we can inherit from `fmt::formatter<std::string_view>` and
use `formatter<std::string_view>::format(foo, ctx);` to implement the
`format()` method with {fmt} v9, but we cannot do this with {fmt} v10,
and we would have following compilation failure:
```
FAILED: service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o
/home/kefu/.local/bin/clang++ -DFMT_DEPRECATED_OSTREAM -DFMT_SHARED -DSCYLLA_BUILD_MODE=release -DSEASTAR_API_LEVEL=7 -DSEASTAR_LOGGER_COMPILE_TIME_FMT -DSEASTAR_LOGGER_TYPE_STDOUT -DSEASTAR_SCHEDULING_GROUPS_COUNT=16 -DSEASTAR_SSTRING -DXXH_PRIVATE_API -DCMAKE_INTDIR=\"RelWithDebInfo\" -I/home/kefu/dev/scylladb -I/home/kefu/dev/scylladb/build/gen -I/home/kefu/dev/scylladb/seastar/include -I/home/kefu/dev/scylladb/build/seastar/gen/include -I/home/kefu/dev/scylladb/build/seastar/gen/src -ffunction-sections -fdata-sections -O3 -g -gz -std=gnu++20 -fvisibility=hidden -Wall -Werror -Wextra -Wno-error=deprecated-declarations -Wimplicit-fallthrough -Wno-c++11-narrowing -Wno-deprecated-copy -Wno-mismatched-tags -Wno-missing-field-initializers -Wno-overloaded-virtual -Wno-unsupported-friend -Wno-enum-constexpr-conversion -Wno-unused-parameter -ffile-prefix-map=/home/kefu/dev/scylladb=. -march=westmere -mllvm -inline-threshold=2500 -fno-slp-vectorize -U_FORTIFY_SOURCE -Werror=unused-result -MD -MT service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o -MF service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o.d -o service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o -c /home/kefu/dev/scylladb/service/topology_state_machine.cc
/home/kefu/dev/scylladb/service/topology_state_machine.cc:254:41: error: no matching member function for call to 'format'
254 | return formatter<std::string_view>::format(it->second, ctx);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
/usr/include/fmt/core.h:2759:22: note: candidate function template not viable: no known conversion from 'seastar::basic_sstring<char, unsigned int, 15>' to 'const fmt::basic_string_view<char>' for 1st argument
2759 | FMT_CONSTEXPR auto format(const T& val, FormatContext& ctx) const
| ^ ~~~~~~~~~~~~
```
because the inherited `format()` method actually comes from
`fmt::formatter<fmt::string_view>`. to reduce the confusion, in this
change, we just inherit from `fmt::format<string_view>`, where
`string_view` is actually `fmt::string_view`. this follows
the document at
https://fmt.dev/latest/api.html#formatting-user-defined-types,
and since there is less indirection under the hood -- we do not
use the specialization created by `FMT_FORMAT_AS` which inherit
from `formatter<fmt::string_view>`, hopefully this can improve
the compilation speed a little bit. also, this change addresses
the build failure with {fmt} v10.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#18299
before this change, we format a sstring with "{:d}", fmtlib would throw
`fmt::format_error` at runtime when formatting it. this is not expected.
so, in this change, we just print the int8_t using `seastar::format()`
in a single pass. and with the format specifier of `#02x` instead of
adding the "0x" prefix manually.
Fixes#14577
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#14578
in C++20, compiler generate operator!=() if the corresponding
operator==() is already defined, the language now understands
that the comparison is symmetric in the new standard.
fortunately, our operator!=() is always equivalent to
`! operator==()`, this matches the behavior of the default
generated operator!=(). so, in this change, all `operator!=`
are removed.
in addition to the defaulted operator!=, C++20 also brings to us
the defaulted operator==() -- it is able to generated the
operator==() if the member-wise lexicographical comparison.
under some circumstances, this is exactly what we need. so,
in this change, if the operator==() is also implemented as
a lexicographical comparison of all memeber variables of the
class/struct in question, it is implemented using the default
generated one by removing its body and mark the function as
`default`. moreover, if the class happen to have other comparison
operators which are implemented using lexicographical comparison,
the default generated `operator<=>` is used in place of
the defaulted `operator==`.
sometimes, we fail to mark the operator== with the `const`
specifier, in this change, to fulfil the need of C++ standard,
and to be more correct, the `const` specifier is added.
also, to generate the defaulted operator==, the operand should
be `const class_name&`, but it is not always the case, in the
class of `version`, we use `version` as the parameter type, to
fulfill the need of the C++ standard, the parameter type is
changed to `const version&` instead. this does not change
the semantic of the comparison operator. and is a more idiomatic
way to pass non-trivial struct as function parameters.
please note, because in C++20, both operator= and operator<=> are
symmetric, some of the operators in `multiprecision` are removed.
they are the symmetric form of the another variant. if they were
not removed, compiler would, for instance, find ambiguous
overloaded operator '=='.
this change is a cleanup to modernize the code base with C++20
features.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13687
this the standard library offers
`std::lexicographical_compare_threeway()`, and we never uses the
last two addition parameters which are not provided by
`std::lexicographical_compare_threeway()`. there is no need to have
the homebrew version of trichotomic compare function.
in this change,
* all occurrences of `lexicographical_tri_compare()` are replaced
with `std::lexicographical_compare_threeway()`.
* ``lexicographical_tri_compare()` is dropped.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13615
this is a part of a series to migrating from `operator<<(ostream&, ..)`
based formatting to fmtlib based formatting. the goal here is to enable
fmtlib to print `composite` with the help of fmt::ostream.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
this is a part of a series to migrating from `operator<<(ostream&, ..)`
based formatting to fmtlib based formatting. the goal here is to enable
fmtlib to print `composite::composite_view` with the help of fmt::ostream.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
this is a part of a series to migrating from `operator<<(ostream&, ..)`
based formatting to fmtlib based formatting. the goal here is to enable
fmtlib to print `composite::component_view` with the help of fmt::ostream.
in this change, '#' is used to add 0x prefix. as fmtlib allows us to add
'0x' prefix using '#' format specifier when printing numbers using 'x'
as its type specifier. see https://fmt.dev/latest/syntax.html
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
now that fmtlib provides fmt::join(). see
https://fmt.dev/latest/api.html#_CPPv4I0EN3fmt4joinE9join_viewIN6detail10iterator_tI5RangeEEN6detail10sentinel_tI5RangeEEERR5Range11string_view
there is not need to revent the wheel. so in this change, the homebrew
join() is replaced with fmt::join().
as fmt::join() returns an join_view(), this could improve the
performance under certain circumstances where the fully materialized
string is not needed.
please note, the goal of this change is to use fmt::join(), and this
change does not intend to improve the performance of existing
implementation based on "operator<<" unless the new implementation is
much more complicated. we will address the unnecessarily materialized
strings in a follow-up commit.
some noteworthy things related to this change:
* unlike the existing `join()`, `fmt::join()` returns a view. so we
have to materialize the view if what we expect is a `sstring`
* `fmt::format()` does not accept a view, so we cannot pass the
return value of `fmt::join()` to `fmt::format()`
* fmtlib does not format a typed pointer, i.e., it does not format,
for instance, a `const std::string*`. but operator<<() always print
a typed pointer. so if we want to format a typed pointer, we either
need to cast the pointer to `void*` or use `fmt::ptr()`.
* fmtlib is not able to pick up the overload of
`operator<<(std::ostream& os, const column_definition* cd)`, so we
have to use a wrapper class of `maybe_column_definition` for printing
a pointer to `column_definition`. since the overload is only used
by the two overloads of
`statement_restrictions::add_single_column_parition_key_restriction()`,
the operator<< for `const column_definition*` is dropped.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Schema related files are moved there. This excludes schema files that
also interact with mutations, because the mutation module depends on
the schema. Those files will have to go into a separate module.
Closes#12858
While debugging legacy_compound_view, I noticed that it cannot be used
as a C++20 std::ranges::input_range because it is missing some trivial
methods. So let's fix this, and make the life of future developers a
little bit easier.
The two trivial methods we need to implement:
1. A postfix increment operator. We already had a prefix increment
operator, but the C++20 concept weakly_iterable also needs postfix.
2. By mistake (this will be corrected in https://wg21.link/P2325R3),
weakly_iterable also required the default_initialized concept, so
our iterator type also needs a default constructor.
We'll never actually use this silly constructor, and when this C++20
standard mistake is corrected, we can remove this constructor.
After this patch, a legacy_compound_view is accepted for the C++20
ranges::input_range concept.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
When iterating over a compound key with legacy_compound_view<>, when the
key is "singular" (i.e., a single column) we need to iterate over just the
component's actual bytes - without the two length bytes or end-of-component
byte. In particular, when the component is an *empty string*, the iteration
should return zero bytes. In other words, we should have begin() == end().
Unfortunately, this is not what happened - for an empty singular key, the
iterator returned for begin() was slightly different from end() - so
code using this iterator would not know there is nothing to iterate.
So in this patch we fix begin() and end() to return the same thing
if we have an empty singular key.
The bug in legacy_compound_view<> (which we fix here) caused a bug in
sstables::key_view::tri_compare(const schema& s, partition_key_view other),
causing it to return wrong results when comparing two empty keys. As a
result we were unable to retrieve a partition with an empty key from the
sstable index. So this patch is necessary to fix support for
empty-string keys in sstables (part of issue #9375).
This patch also includes a unit-test for this bug. We test it in the
context of sstables::key_view::tri_compare(), where it was first
discovered, and also test the legacy_compound_view itself. The included
test used to fail in both places before this patch, and pass after it.
Fixes#10178
Refs #9375
Signed-off-by: Nadav Har'El <nyh@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
If x is of type std::strong_ordering, then "x <=> 0" is equivalent to
x. These no-ops were inserted during #1449 fixes, but are now unnecessary.
They have potential for harm, since they can hide an accidental of the
type of x to an arithmetic type, so remove them.
Ref #1449.
Eliminate not used includes and replace some more includes
with forward declarations where appropriate.
Signed-off-by: Pavel Solodovnikov <pa.solodovnikov@scylladb.com>
Verify that the input types are iterators and their value types are compatible
with the compare function.
Because some of the inputs were not actually valid iterators, they are adjusted
too.
Closes#7631
* github.com:scylladb/scylla:
types: add constraint on lexicographical_tri_compare()
composite: make composite::iterator a real input_iterator
compound: make compount_type::iterator a real input_iterator
If any of the compared bytes_view's is empty
consider the empty prefix is same and proceed to compare
the size of the suffix.
A similar issue exists in legacy_compound_view::tri_comparator::operator().
It too must not pass nullptr to memcmp if any of the compared byte_view's
is empty.
Fixes#6797
Refs #6814
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Test: unit(dev)
Branches: all
Message-Id: <20200709123453.955569-1-bhalevy@scylladb.com>
So that nested exceptions are not lost. Also, marshal exceptions, the
ones we have in these places, already have a backtrace, so might as well
use that, instead of creating a new one, loosing unwound frames.
Signed-off-by: Botond Dénes <bdenes@scylladb.com>
Message-Id: <20200507091405.244544-1-bdenes@scylladb.com>
But only non-validation error paths. When validating we do expect it to
maybe fail, so we don't want to generate cores for validation.
Validation is in fact a de-serialization pass with some additional
checks. To be able to keep reusing the same code for de-serialization
and validation just with different error handling, introduce a
`strict_mode` flag that can be passed to `composite::iterator`
constructor. When in strict mode (the default) the iterator will convert
any `marshal_exception` thrown during the de-serialization to
`on_internal_error()`.
We don't want anybody to use the iterator in non-strict mode, besides
validation, so the iterator constructors are made private. This is
standard practice for iterators anyway.
Until now this was open-coded in `sstables::validate_min_max_metadata()`.
We want to cover non-validation compound de-serialization error-paths
with `on_internal_error()` and so we need more control over how
compounds are validated. As a first step we want to centralize
validation in the class itself as in the next patches they will use
private APIs to bypass `on_internal_error()` in the error paths during
validation.
Not just bytes::output_iterator. Allow writing into streams other than
just `bytes`. In fact we should be very careful with writing into
`bytes` as they require potentially large contiguous allocations.
The `write()` method is now templatized also on the type of its first
argument, which now accepts any CharOutputIterator. Due to our poor
usage of namespace this now collides with `write` defined inside
`db/commitlog/commitlog.cc`. Luckily, the latter doesn't really have to
be templatized on the data type it reads from, and de-templatizing it
resolves the clash.
sprint() recently became more strict, throwing on sprint("%s", 5). Replace
with the more modern format().
Mechanically converted with https://github.com/avikivity/unsprint.
The universal reference was introduced so we could bind an rvalue to
the argument, but it would have sufficed to make the argument a const
reference. This is also more consistent with the function's other
overload.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Message-Id: <20171129132758.19654-1-duarte@scylladb.com>
This patch changes some factory functions so that they don't assume
the schema is compound.
This enables some code simplification in
sstables::write_column_name().
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
When we are exploding a compound key we know already that there is more
than one component, but we have no easy way of determining how many of
them are going to be there. Let's reserve space for a few elements so
that we avoid an excessive number of reallocations in case of
medium-sized keys.
composite_view's is_static function is wrong because:
1) It doesn't guard against the composite being a compound;
2) Doesn't deal with widening due to integral promotions and
consequent sign extension.
This patch fixes this by ensuring there's only one correct
implementation of is_static, to avoid code duplication and
enforce test coverage.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Message-Id: <1469616205-4550-2-git-send-email-duarte@scylladb.com>
If a composite is not a compound, then it doesn't carry a length
prefix where static information is encoded. In its absence, a
non-compound composite can never be static.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Message-Id: <1469397561-7748-1-git-send-email-duarte@scylladb.com>
