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#include "libexpr/attr-set.hh"
#include <new>
#include <absl/container/btree_map.h>
#include <gc/gc_cpp.h>
#include <glog/logging.h>
#include "libexpr/eval-inline.hh"
namespace nix {
static Bindings ZERO_BINDINGS;
// This function inherits its name from previous implementations, in
// which Bindings was backed by an array of elements which was scanned
// linearly.
//
// In that setup, inserting duplicate elements would always yield the
// first element (until the next sort, which wasn't stable, after
// which things are more or less undefined).
//
// This behaviour is mimicked by using .insert(), which will *not*
// override existing values.
void Bindings::push_back(const Attr& attr) {
assert(this != &ZERO_BINDINGS);
auto [_, inserted] = attributes_.insert({attr.name, attr});
if (!inserted) {
DLOG(WARNING) << "attempted to insert duplicate attribute for key '"
<< attr.name << "'";
}
}
size_t Bindings::size() const { return attributes_.size(); }
bool Bindings::empty() { return attributes_.empty(); }
std::vector<const Attr*> Bindings::SortedByKeys() {
std::vector<const Attr*> res;
res.reserve(attributes_.size());
for (const auto& [key, value] : attributes_) {
res.emplace_back(&value);
}
return res;
}
Bindings::iterator Bindings::find(const Symbol& name) {
return attributes_.find(name);
}
Bindings::iterator Bindings::begin() { return attributes_.begin(); }
Bindings::iterator Bindings::end() { return attributes_.end(); }
Bindings* Bindings::NewGC(size_t capacity) {
if (capacity == 0) {
return &ZERO_BINDINGS;
}
return new (GC) Bindings;
}
Bindings* Bindings::Merge(const Bindings& lhs, const Bindings& rhs) {
auto bindings = NewGC(lhs.size() + rhs.size());
// Values are merged by inserting the entire iterator range of both
// input sets. The right-hand set (the values of which take
// precedence) is inserted *first* because the range insertion
// method does not override values.
bindings->attributes_.insert(rhs.attributes_.cbegin(),
rhs.attributes_.cend());
bindings->attributes_.insert(lhs.attributes_.cbegin(),
lhs.attributes_.cend());
return bindings;
}
void EvalState::mkAttrs(Value& v, size_t capacity) {
clearValue(v);
v.type = tAttrs;
v.attrs = Bindings::NewGC(capacity);
nrAttrsets++;
nrAttrsInAttrsets += capacity;
}
/* Create a new attribute named 'name' on an existing attribute set stored
in 'vAttrs' and return the newly allocated Value which is associated with
this attribute. */
Value* EvalState::allocAttr(Value& vAttrs, const Symbol& name) {
Value* v = allocValue();
vAttrs.attrs->push_back(Attr(name, v));
return v;
}
} // namespace nix
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