Make Buildable a std::variant

I think this better captures the intent of what's going on: we either
have an opaque store path, or a drv path with some outputs.

Having this structure will also help us support CA derivations: we'll
have to allow the outpath paths to be optional, so the structure we gain
now makes up for the structure we loose then.
This commit is contained in:
John Ericson 2020-07-23 19:02:57 +00:00
parent a7b8f79938
commit e1de1fe0d8
8 changed files with 98 additions and 79 deletions

View file

@ -24,10 +24,6 @@ std::string makeFixedOutputCA(FileIngestionMethod method, const Hash & hash)
+ hash.to_string(Base32, true);
}
// FIXME Put this somewhere?
template<class... Ts> struct overloaded : Ts... { using Ts::operator()...; };
template<class... Ts> overloaded(Ts...) -> overloaded<Ts...>;
std::string renderContentAddress(ContentAddress ca) {
return std::visit(overloaded {
[](TextHash th) {

View file

@ -865,10 +865,6 @@ void ValidPathInfo::sign(const Store & store, const SecretKey & secretKey)
sigs.insert(secretKey.signDetached(fingerprint(store)));
}
// FIXME Put this somewhere?
template<class... Ts> struct overloaded : Ts... { using Ts::operator()...; };
template<class... Ts> overloaded(Ts...) -> overloaded<Ts...>;
bool ValidPathInfo::isContentAddressed(const Store & store) const
{
if (! ca) return false;

View file

@ -601,4 +601,9 @@ constexpr auto enumerate(T && iterable)
}
// C++17 std::visit boilerplate
template<class... Ts> struct overloaded : Ts... { using Ts::operator()...; };
template<class... Ts> overloaded(Ts...) -> overloaded<Ts...>;
}

View file

@ -57,17 +57,24 @@ struct CmdBuild : InstallablesCommand, MixDryRun, MixProfile
if (dryRun) return;
if (outLink != "") {
for (size_t i = 0; i < buildables.size(); ++i) {
for (auto & output : buildables[i].outputs)
if (auto store2 = store.dynamic_pointer_cast<LocalFSStore>()) {
if (outLink != "")
if (auto store2 = store.dynamic_pointer_cast<LocalFSStore>())
for (size_t i = 0; i < buildables.size(); ++i)
std::visit(overloaded {
[&](BuildableOpaque bo) {
std::string symlink = outLink;
if (i) symlink += fmt("-%d", i);
store2->addPermRoot(bo.path, absPath(symlink), true);
},
[&](BuildableFromDrv bfd) {
for (auto & output : bfd.outputs) {
std::string symlink = outLink;
if (i) symlink += fmt("-%d", i);
if (output.first != "out") symlink += fmt("-%s", output.first);
store2->addPermRoot(output.second, absPath(symlink), true);
}
}
}
},
}, buildables[i]);
updateProfile(buildables);
}

View file

@ -131,11 +131,18 @@ void MixProfile::updateProfile(const Buildables & buildables)
std::optional<StorePath> result;
for (auto & buildable : buildables) {
for (auto & output : buildable.outputs) {
std::visit(overloaded {
[&](BuildableOpaque bo) {
result = bo.path;
},
[&](BuildableFromDrv bfd) {
for (auto & output : bfd.outputs) {
if (result)
throw Error("'--profile' requires that the arguments produce a single store path, but there are multiple");
result = output.second;
}
},
}, buildable);
}
if (!result)

View file

@ -307,16 +307,15 @@ struct InstallableStorePath : Installable
for (auto & [name, output] : store->readDerivation(storePath).outputs)
outputs.emplace(name, output.path);
return {
Buildable {
BuildableFromDrv {
.drvPath = storePath,
.outputs = std::move(outputs)
}
};
} else {
return {
Buildable {
.drvPath = {},
.outputs = {{"out", storePath}}
BuildableOpaque {
.path = storePath,
}
};
}
@ -332,32 +331,19 @@ Buildables InstallableValue::toBuildables()
{
Buildables res;
StorePathSet drvPaths;
std::map<StorePath, OutputPathMap> drvsToOutputs;
// Group by derivation, helps with .all in particular
for (auto & drv : toDerivations()) {
Buildable b{.drvPath = drv.drvPath};
drvPaths.insert(drv.drvPath);
auto outputName = drv.outputName;
if (outputName == "")
throw Error("derivation '%s' lacks an 'outputName' attribute", state->store->printStorePath(*b.drvPath));
b.outputs.emplace(outputName, drv.outPath);
res.push_back(std::move(b));
throw Error("derivation '%s' lacks an 'outputName' attribute", state->store->printStorePath(drv.drvPath));
drvsToOutputs[drv.drvPath].insert_or_assign(outputName, drv.outPath);
}
// Hack to recognize .all: if all drvs have the same drvPath,
// merge the buildables.
if (drvPaths.size() == 1) {
Buildable b{.drvPath = *drvPaths.begin()};
for (auto & b2 : res)
for (auto & output : b2.outputs)
b.outputs.insert_or_assign(output.first, output.second);
Buildables bs;
bs.push_back(std::move(b));
return bs;
} else
for (auto & i : drvsToOutputs)
res.push_back(BuildableFromDrv { i.first, i.second });
return res;
}
@ -653,14 +639,17 @@ Buildables build(ref<Store> store, Realise mode,
for (auto & i : installables) {
for (auto & b : i->toBuildables()) {
if (b.drvPath) {
std::visit(overloaded {
[&](BuildableOpaque bo) {
pathsToBuild.push_back({bo.path});
},
[&](BuildableFromDrv bfd) {
StringSet outputNames;
for (auto & output : b.outputs)
for (auto & output : bfd.outputs)
outputNames.insert(output.first);
pathsToBuild.push_back({*b.drvPath, outputNames});
} else
for (auto & output : b.outputs)
pathsToBuild.push_back({output.second});
pathsToBuild.push_back({bfd.drvPath, outputNames});
},
}, b);
buildables.push_back(std::move(b));
}
}
@ -681,16 +670,23 @@ StorePathSet toStorePaths(ref<Store> store,
if (operateOn == OperateOn::Output) {
for (auto & b : build(store, mode, installables))
for (auto & output : b.outputs)
std::visit(overloaded {
[&](BuildableOpaque bo) {
outPaths.insert(bo.path);
},
[&](BuildableFromDrv bfd) {
for (auto & output : bfd.outputs)
outPaths.insert(output.second);
},
}, b);
} else {
if (mode == Realise::Nothing)
settings.readOnlyMode = true;
for (auto & i : installables)
for (auto & b : i->toBuildables())
if (b.drvPath)
outPaths.insert(*b.drvPath);
if (auto bfd = std::get_if<BuildableFromDrv>(&b))
outPaths.insert(bfd->drvPath);
}
return outPaths;
@ -714,20 +710,21 @@ StorePathSet toDerivations(ref<Store> store,
StorePathSet drvPaths;
for (auto & i : installables)
for (auto & b : i->toBuildables()) {
if (!b.drvPath) {
for (auto & b : i->toBuildables())
std::visit(overloaded {
[&](BuildableOpaque bo) {
if (!useDeriver)
throw Error("argument '%s' did not evaluate to a derivation", i->what());
for (auto & output : b.outputs) {
auto derivers = store->queryValidDerivers(output.second);
auto derivers = store->queryValidDerivers(bo.path);
if (derivers.empty())
throw Error("'%s' does not have a known deriver", i->what());
// FIXME: use all derivers?
drvPaths.insert(*derivers.begin());
}
} else
drvPaths.insert(*b.drvPath);
}
},
[&](BuildableFromDrv bfd) {
drvPaths.insert(bfd.drvPath);
},
}, b);
return drvPaths;
}

View file

@ -14,12 +14,20 @@ struct SourceExprCommand;
namespace eval_cache { class EvalCache; class AttrCursor; }
struct Buildable
{
std::optional<StorePath> drvPath;
struct BuildableOpaque {
StorePath path;
};
struct BuildableFromDrv {
StorePath drvPath;
std::map<std::string, StorePath> outputs;
};
typedef std::variant<
BuildableOpaque,
BuildableFromDrv
> Buildable;
typedef std::vector<Buildable> Buildables;
struct App

View file

@ -45,11 +45,14 @@ struct CmdLog : InstallableCommand
RunPager pager;
for (auto & sub : subs) {
auto log = b.drvPath ? sub->getBuildLog(*b.drvPath) : nullptr;
for (auto & output : b.outputs) {
if (log) break;
log = sub->getBuildLog(output.second);
}
auto log = std::visit(overloaded {
[&](BuildableOpaque bo) {
return sub->getBuildLog(bo.path);
},
[&](BuildableFromDrv bfd) {
return sub->getBuildLog(bfd.drvPath);
},
}, b);
if (!log) continue;
stopProgressBar();
printInfo("got build log for '%s' from '%s'", installable->what(), sub->getUri());