lix/src/nix/installables.cc
2020-06-16 22:20:18 +02:00

346 lines
9.8 KiB
C++

#include "command.hh"
#include "attr-path.hh"
#include "common-eval-args.hh"
#include "derivations.hh"
#include "eval-inline.hh"
#include "eval.hh"
#include "get-drvs.hh"
#include "store-api.hh"
#include "shared.hh"
#include <regex>
namespace nix {
SourceExprCommand::SourceExprCommand()
{
addFlag({
.longName = "file",
.shortName = 'f',
.description = "evaluate FILE rather than the default",
.labels = {"file"},
.handler = {&file}
});
}
Value * SourceExprCommand::getSourceExpr(EvalState & state)
{
if (vSourceExpr) return *vSourceExpr;
auto sToplevel = state.symbols.create("_toplevel");
vSourceExpr = allocRootValue(state.allocValue());
if (file != "")
state.evalFile(lookupFileArg(state, file), **vSourceExpr);
else {
/* Construct the installation source from $NIX_PATH. */
auto searchPath = state.getSearchPath();
state.mkAttrs(**vSourceExpr, 1024);
mkBool(*state.allocAttr(**vSourceExpr, sToplevel), true);
std::unordered_set<std::string> seen;
auto addEntry = [&](const std::string & name) {
if (name == "") return;
if (!seen.insert(name).second) return;
Value * v1 = state.allocValue();
mkPrimOpApp(*v1, state.getBuiltin("findFile"), state.getBuiltin("nixPath"));
Value * v2 = state.allocValue();
mkApp(*v2, *v1, mkString(*state.allocValue(), name));
mkApp(*state.allocAttr(**vSourceExpr, state.symbols.create(name)),
state.getBuiltin("import"), *v2);
};
for (auto & i : searchPath)
/* Hack to handle channels. */
if (i.first.empty() && pathExists(i.second + "/manifest.nix")) {
for (auto & j : readDirectory(i.second))
if (j.name != "manifest.nix"
&& pathExists(fmt("%s/%s/default.nix", i.second, j.name)))
addEntry(j.name);
} else
addEntry(i.first);
(*vSourceExpr)->attrs->sort();
}
return *vSourceExpr;
}
ref<EvalState> SourceExprCommand::getEvalState()
{
if (!evalState)
evalState = std::make_shared<EvalState>(searchPath, getStore());
return ref<EvalState>(evalState);
}
Buildable Installable::toBuildable()
{
auto buildables = toBuildables();
if (buildables.size() != 1)
throw Error("installable '%s' evaluates to %d derivations, where only one is expected", what(), buildables.size());
return std::move(buildables[0]);
}
struct InstallableStorePath : Installable
{
ref<Store> store;
StorePath storePath;
InstallableStorePath(ref<Store> store, const Path & storePath)
: store(store), storePath(store->parseStorePath(storePath)) { }
std::string what() override { return store->printStorePath(storePath); }
Buildables toBuildables() override
{
std::map<std::string, StorePath> outputs;
outputs.insert_or_assign("out", storePath);
Buildable b{
.drvPath = storePath.isDerivation() ? storePath : std::optional<StorePath>(),
.outputs = std::move(outputs)
};
Buildables bs;
bs.push_back(std::move(b));
return bs;
}
std::optional<StorePath> getStorePath() override
{
return storePath;
}
};
struct InstallableValue : Installable
{
SourceExprCommand & cmd;
InstallableValue(SourceExprCommand & cmd) : cmd(cmd) { }
Buildables toBuildables() override
{
auto state = cmd.getEvalState();
auto v = toValue(*state).first;
Bindings & autoArgs = *cmd.getAutoArgs(*state);
DrvInfos drvs;
getDerivations(*state, *v, "", autoArgs, drvs, false);
Buildables res;
StorePathSet drvPaths;
for (auto & drv : drvs) {
Buildable b{.drvPath = state->store->parseStorePath(drv.queryDrvPath())};
drvPaths.insert(*b.drvPath);
auto outputName = drv.queryOutputName();
if (outputName == "")
throw Error("derivation '%s' lacks an 'outputName' attribute", state->store->printStorePath(*b.drvPath));
b.outputs.emplace(outputName, state->store->parseStorePath(drv.queryOutPath()));
res.push_back(std::move(b));
}
// 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
return res;
}
};
struct InstallableExpr : InstallableValue
{
std::string text;
InstallableExpr(SourceExprCommand & cmd, const std::string & text)
: InstallableValue(cmd), text(text) { }
std::string what() override { return text; }
std::pair<Value *, Pos> toValue(EvalState & state) override
{
auto v = state.allocValue();
state.eval(state.parseExprFromString(text, absPath(".")), *v);
return {v, noPos};
}
};
struct InstallableAttrPath : InstallableValue
{
std::string attrPath;
InstallableAttrPath(SourceExprCommand & cmd, const std::string & attrPath)
: InstallableValue(cmd), attrPath(attrPath)
{ }
std::string what() override { return attrPath; }
std::pair<Value *, Pos> toValue(EvalState & state) override
{
auto source = cmd.getSourceExpr(state);
Bindings & autoArgs = *cmd.getAutoArgs(state);
auto v = findAlongAttrPath(state, attrPath, autoArgs, *source).first;
state.forceValue(*v);
return {v, noPos};
}
};
// FIXME: extend
std::string attrRegex = R"([A-Za-z_][A-Za-z0-9-_+]*)";
static std::regex attrPathRegex(fmt(R"(%1%(\.%1%)*)", attrRegex));
static std::vector<std::shared_ptr<Installable>> parseInstallables(
SourceExprCommand & cmd, ref<Store> store, std::vector<std::string> ss, bool useDefaultInstallables)
{
std::vector<std::shared_ptr<Installable>> result;
if (ss.empty() && useDefaultInstallables) {
if (cmd.file == "")
cmd.file = ".";
ss = {""};
}
for (auto & s : ss) {
if (s.compare(0, 1, "(") == 0)
result.push_back(std::make_shared<InstallableExpr>(cmd, s));
else if (s.find("/") != std::string::npos) {
auto path = store->toStorePath(store->followLinksToStore(s));
if (store->isStorePath(path))
result.push_back(std::make_shared<InstallableStorePath>(store, path));
}
else if (s == "" || std::regex_match(s, attrPathRegex))
result.push_back(std::make_shared<InstallableAttrPath>(cmd, s));
else
throw UsageError("don't know what to do with argument '%s'", s);
}
return result;
}
std::shared_ptr<Installable> parseInstallable(
SourceExprCommand & cmd, ref<Store> store, const std::string & installable,
bool useDefaultInstallables)
{
auto installables = parseInstallables(cmd, store, {installable}, false);
assert(installables.size() == 1);
return installables.front();
}
Buildables build(ref<Store> store, RealiseMode mode,
std::vector<std::shared_ptr<Installable>> installables)
{
if (mode != Build)
settings.readOnlyMode = true;
Buildables buildables;
std::vector<StorePathWithOutputs> pathsToBuild;
for (auto & i : installables) {
for (auto & b : i->toBuildables()) {
if (b.drvPath) {
StringSet outputNames;
for (auto & output : b.outputs)
outputNames.insert(output.first);
pathsToBuild.push_back({*b.drvPath, outputNames});
} else
for (auto & output : b.outputs)
pathsToBuild.push_back({output.second});
buildables.push_back(std::move(b));
}
}
if (mode == DryRun)
printMissing(store, pathsToBuild, lvlError);
else if (mode == Build)
store->buildPaths(pathsToBuild);
return buildables;
}
StorePathSet toStorePaths(ref<Store> store, RealiseMode mode,
std::vector<std::shared_ptr<Installable>> installables)
{
StorePathSet outPaths;
for (auto & b : build(store, mode, installables))
for (auto & output : b.outputs)
outPaths.insert(output.second);
return outPaths;
}
StorePath toStorePath(ref<Store> store, RealiseMode mode,
std::shared_ptr<Installable> installable)
{
auto paths = toStorePaths(store, mode, {installable});
if (paths.size() != 1)
throw Error("argument '%s' should evaluate to one store path", installable->what());
return *paths.begin();
}
StorePathSet toDerivations(ref<Store> store,
std::vector<std::shared_ptr<Installable>> installables, bool useDeriver)
{
StorePathSet drvPaths;
for (auto & i : installables)
for (auto & b : i->toBuildables()) {
if (!b.drvPath) {
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);
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);
}
return drvPaths;
}
void InstallablesCommand::prepare()
{
installables = parseInstallables(*this, getStore(), _installables, useDefaultInstallables());
}
void InstallableCommand::prepare()
{
installable = parseInstallable(*this, getStore(), _installable, false);
}
}