Decode string context straight to using StorePaths

I gather decoding happens on demand, so I hope don't think this should
have any perf implications one way or the other.
This commit is contained in:
John Ericson 2022-03-12 00:28:00 +00:00
parent 91adfb8894
commit 4d6a3806d2
7 changed files with 38 additions and 24 deletions

View file

@ -21,6 +21,8 @@ struct AttrDb
{
std::atomic_bool failed{false};
const Store & cfg;
struct State
{
SQLite db;
@ -33,8 +35,9 @@ struct AttrDb
std::unique_ptr<Sync<State>> _state;
AttrDb(const Hash & fingerprint)
: _state(std::make_unique<Sync<State>>())
AttrDb(const Store & cfg, const Hash & fingerprint)
: cfg(cfg)
, _state(std::make_unique<Sync<State>>())
{
auto state(_state->lock());
@ -257,7 +260,7 @@ struct AttrDb
NixStringContext context;
if (!queryAttribute.isNull(3))
for (auto & s : tokenizeString<std::vector<std::string>>(queryAttribute.getStr(3), ";"))
context.push_back(decodeContext(s));
context.push_back(decodeContext(cfg, s));
return {{rowId, string_t{queryAttribute.getStr(2), context}}};
}
case AttrType::Bool:
@ -274,10 +277,10 @@ struct AttrDb
}
};
static std::shared_ptr<AttrDb> makeAttrDb(const Hash & fingerprint)
static std::shared_ptr<AttrDb> makeAttrDb(const Store & cfg, const Hash & fingerprint)
{
try {
return std::make_shared<AttrDb>(fingerprint);
return std::make_shared<AttrDb>(cfg, fingerprint);
} catch (SQLiteError &) {
ignoreException();
return nullptr;
@ -288,7 +291,7 @@ EvalCache::EvalCache(
std::optional<std::reference_wrapper<const Hash>> useCache,
EvalState & state,
RootLoader rootLoader)
: db(useCache ? makeAttrDb(*useCache) : nullptr)
: db(useCache ? makeAttrDb(*state.store, *useCache) : nullptr)
, state(state)
, rootLoader(rootLoader)
{
@ -546,7 +549,7 @@ string_t AttrCursor::getStringWithContext()
if (auto s = std::get_if<string_t>(&cachedValue->second)) {
bool valid = true;
for (auto & c : s->second) {
if (!root->state.store->isValidPath(root->state.store->parseStorePath(c.first))) {
if (!root->state.store->isValidPath(c.first)) {
valid = false;
break;
}
@ -563,7 +566,7 @@ string_t AttrCursor::getStringWithContext()
auto & v = forceValue();
if (v.type() == nString)
return {v.string.s, v.getContext()};
return {v.string.s, v.getContext(*root->state.store)};
else if (v.type() == nPath)
return {v.path, {}};
else

View file

@ -1903,13 +1903,22 @@ std::string_view EvalState::forceString(Value & v, const Pos & pos)
/* Decode a context string !<name>!<path> into a pair <path,
name>. */
NixStringContextElem decodeContext(std::string_view s)
NixStringContextElem decodeContext(const Store & store, std::string_view s)
{
if (s.at(0) == '!') {
size_t index = s.find("!", 1);
return {std::string(s.substr(index + 1)), std::string(s.substr(1, index - 1))};
return {
store.parseStorePath(s.substr(index + 1)),
std::string(s.substr(1, index - 1)),
};
} else
return {s.at(0) == '/' ? std::string(s) : std::string(s.substr(1)), ""};
return {
store.parseStorePath(
s.at(0) == '/'
? s
: s.substr(1)),
"",
};
}
@ -1921,13 +1930,13 @@ void copyContext(const Value & v, PathSet & context)
}
NixStringContext Value::getContext()
NixStringContext Value::getContext(const Store & store)
{
NixStringContext res;
assert(internalType == tString);
if (string.context)
for (const char * * p = string.context; *p; ++p)
res.push_back(decodeContext(*p));
res.push_back(decodeContext(store, *p));
return res;
}

View file

@ -17,7 +17,7 @@
namespace nix {
class Store;
struct Store;
class EvalState;
class StorePath;
enum RepairFlag : bool;
@ -430,7 +430,7 @@ std::string showType(const Value & v);
/* Decode a context string !<name>!<path> into a pair <path,
name>. */
NixStringContextElem decodeContext(std::string_view s);
NixStringContextElem decodeContext(const Store & store, std::string_view s);
/* If `path' refers to a directory, then append "/default.nix". */
Path resolveExprPath(Path path);

View file

@ -43,8 +43,8 @@ StringMap EvalState::realiseContext(const PathSet & context)
StringMap res;
for (auto & i : context) {
auto [ctxS, outputName] = decodeContext(i);
auto ctx = store->parseStorePath(ctxS);
auto [ctx, outputName] = decodeContext(*store, i);
auto ctxS = store->printStorePath(ctx);
if (!store->isValidPath(ctx))
throw InvalidPathError(store->printStorePath(ctx));
if (!outputName.empty() && ctx.isDerivation()) {
@ -1118,8 +1118,8 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * *
/* Handle derivation outputs of the form !<name>!<path>. */
else if (path.at(0) == '!') {
auto ctx = decodeContext(path);
drv.inputDrvs[state.store->parseStorePath(ctx.first)].insert(ctx.second);
auto ctx = decodeContext(*state.store, path);
drv.inputDrvs[ctx.first].insert(ctx.second);
}
/* Otherwise it's a source file. */

View file

@ -82,8 +82,8 @@ static void prim_getContext(EvalState & state, const Pos & pos, Value * * args,
drv = std::string(p, 1);
path = &drv;
} else if (p.at(0) == '!') {
NixStringContextElem ctx = decodeContext(p);
drv = ctx.first;
NixStringContextElem ctx = decodeContext(*state.store, p);
drv = state.store->printStorePath(ctx.first);
output = ctx.second;
path = &drv;
}

View file

@ -57,6 +57,8 @@ struct ExprLambda;
struct PrimOp;
class Symbol;
struct Pos;
class StorePath;
class Store;
class EvalState;
class XMLWriter;
class JSONPlaceholder;
@ -64,7 +66,7 @@ class JSONPlaceholder;
typedef int64_t NixInt;
typedef double NixFloat;
typedef std::pair<Path, std::string> NixStringContextElem;
typedef std::pair<StorePath, std::string> NixStringContextElem;
typedef std::vector<NixStringContextElem> NixStringContext;
/* External values must descend from ExternalValueBase, so that
@ -370,7 +372,7 @@ public:
non-trivial. */
bool isTrivial() const;
NixStringContext getContext();
NixStringContext getContext(const Store &);
auto listItems()
{

View file

@ -70,7 +70,7 @@ UnresolvedApp Installable::toApp(EvalState & state)
std::vector<StorePathWithOutputs> context2;
for (auto & [path, name] : context)
context2.push_back({state.store->parseStorePath(path), {name}});
context2.push_back({path, {name}});
return UnresolvedApp{App {
.context = std::move(context2),