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#include "user-env.hh"
#include "derivations.hh"
#include "store-api.hh"
#include "path-with-outputs.hh"
#include "local-fs-store.hh"
#include "globals.hh"
#include "shared.hh"
#include "eval.hh"
#include "eval-inline.hh"
#include "profiles.hh"
#include "print-ambiguous.hh"
#include <limits>
#include <sstream>
namespace nix {
bool createUserEnv(EvalState & state, DrvInfos & elems,
const Path & profile, bool keepDerivations,
const std::string & lockToken)
{
/* Build the components in the user environment, if they don't
exist already. */
std::vector<StorePathWithOutputs> drvsToBuild;
for (auto & i : elems)
if (auto drvPath = i.queryDrvPath())
drvsToBuild.push_back({*drvPath});
debug("building user environment dependencies");
state.store->buildPaths(
toDerivedPaths(drvsToBuild),
state.repair ? bmRepair : bmNormal);
/* Construct the whole top level derivation. */
StorePathSet references;
Value manifest;
state.mkList(manifest, elems.size());
size_t n = 0;
for (auto & i : elems) {
/* Create a pseudo-derivation containing the name, system,
output paths, and optionally the derivation path, as well
as the meta attributes. */
std::optional<StorePath> drvPath = keepDerivations ? i.queryDrvPath() : std::nullopt;
DrvInfo::Outputs outputs = i.queryOutputs(true, true);
StringSet metaNames = i.queryMetaNames();
auto attrs = state.buildBindings(7 + outputs.size());
attrs.alloc(state.sType).mkString("derivation");
attrs.alloc(state.sName).mkString(i.queryName());
auto system = i.querySystem();
if (!system.empty())
attrs.alloc(state.sSystem).mkString(system);
attrs.alloc(state.sOutPath).mkString(state.store->printStorePath(i.queryOutPath()));
if (drvPath)
attrs.alloc(state.sDrvPath).mkString(state.store->printStorePath(*drvPath));
// Copy each output meant for installation.
auto & vOutputs = attrs.alloc(state.sOutputs);
state.mkList(vOutputs, outputs.size());
for (const auto & [m, j] : enumerate(outputs)) {
(vOutputs.listElems()[m] = state.allocValue())->mkString(j.first);
auto outputAttrs = state.buildBindings(2);
outputAttrs.alloc(state.sOutPath).mkString(state.store->printStorePath(*j.second));
attrs.alloc(j.first).mkAttrs(outputAttrs);
/* This is only necessary when installing store paths, e.g.,
`nix-env -i /nix/store/abcd...-foo'. */
state.store->addTempRoot(*j.second);
state.store->ensurePath(*j.second);
references.insert(*j.second);
}
// Copy the meta attributes.
auto meta = state.buildBindings(metaNames.size());
for (auto & j : metaNames) {
Value * v = i.queryMeta(j);
if (!v) continue;
meta.insert(state.symbols.create(j), v);
}
attrs.alloc(state.sMeta).mkAttrs(meta);
(manifest.listElems()[n++] = state.allocValue())->mkAttrs(attrs);
if (drvPath) references.insert(*drvPath);
}
/* Also write a copy of the list of user environment elements to
the store; we need it for future modifications of the
environment. */
std::ostringstream str;
printAmbiguous(manifest, state.symbols, str, nullptr, std::numeric_limits<int>::max());
auto manifestFile = state.store->addTextToStore("env-manifest.nix",
str.str(), references);
/* Get the environment builder expression. */
Value envBuilder;
state.eval(state.parseExprFromString(
#include "buildenv.nix.gen.hh"
, state.rootPath(CanonPath::root)), envBuilder);
/* Construct a Nix expression that calls the user environment
builder with the manifest as argument. */
auto attrs = state.buildBindings(3);
state.mkStorePathString(manifestFile, attrs.alloc("manifest"));
attrs.insert(state.symbols.create("derivations"), &manifest);
Value args;
args.mkAttrs(attrs);
Value topLevel;
topLevel.mkApp(&envBuilder, &args);
/* Evaluate it. */
debug("evaluating user environment builder");
state.forceValue(topLevel, topLevel.determinePos(noPos));
NixStringContext context;
Attr & aDrvPath(*topLevel.attrs->find(state.sDrvPath));
auto topLevelDrv = state.coerceToStorePath(aDrvPath.pos, *aDrvPath.value, context, "");
Attr & aOutPath(*topLevel.attrs->find(state.sOutPath));
auto topLevelOut = state.coerceToStorePath(aOutPath.pos, *aOutPath.value, context, "");
/* Realise the resulting store expression. */
debug("building user environment");
std::vector<StorePathWithOutputs> topLevelDrvs;
topLevelDrvs.push_back({topLevelDrv});
state.store->buildPaths(
toDerivedPaths(topLevelDrvs),
state.repair ? bmRepair : bmNormal);
/* Switch the current user environment to the output path. */
auto store2 = state.store.dynamic_pointer_cast<LocalFSStore>();
if (store2) {
PathLocks lock;
lockProfile(lock, profile);
Path lockTokenCur = optimisticLockProfile(profile);
if (lockToken != lockTokenCur) {
printInfo("profile '%1%' changed while we were busy; restarting", profile);
return false;
}
debug("switching to new user environment");
Path generation = createGeneration(*store2, profile, topLevelOut);
switchLink(profile, generation);
}
return true;
}
}
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