tvl-depot/third_party/nix/src/libstore/local-binary-cache-store.cc
2020-05-20 22:27:37 +01:00

91 lines
2.5 KiB
C++

#include <utility>
#include "binary-cache-store.hh"
#include "globals.hh"
#include "nar-info-disk-cache.hh"
namespace nix {
class LocalBinaryCacheStore : public BinaryCacheStore {
private:
Path binaryCacheDir;
public:
LocalBinaryCacheStore(const Params& params, Path binaryCacheDir)
: BinaryCacheStore(params), binaryCacheDir(std::move(binaryCacheDir)) {}
void init() override;
std::string getUri() override { return "file://" + binaryCacheDir; }
protected:
bool fileExists(const std::string& path) override;
void upsertFile(const std::string& path, const std::string& data,
const std::string& mimeType) override;
void getFile(const std::string& path, Sink& sink) override {
try {
readFile(binaryCacheDir + "/" + path, sink);
} catch (SysError& e) {
if (e.errNo == ENOENT) {
throw NoSuchBinaryCacheFile("file '%s' does not exist in binary cache",
path);
}
}
}
PathSet queryAllValidPaths() override {
PathSet paths;
for (auto& entry : readDirectory(binaryCacheDir)) {
if (entry.name.size() != 40 || !hasSuffix(entry.name, ".narinfo")) {
continue;
}
paths.insert(storeDir + "/" +
entry.name.substr(0, entry.name.size() - 8));
}
return paths;
}
};
void LocalBinaryCacheStore::init() {
createDirs(binaryCacheDir + "/nar");
BinaryCacheStore::init();
}
static void atomicWrite(const Path& path, const std::string& s) {
Path tmp = path + ".tmp." + std::to_string(getpid());
AutoDelete del(tmp, false);
writeFile(tmp, s);
if (rename(tmp.c_str(), path.c_str()) != 0) {
throw SysError(format("renaming '%1%' to '%2%'") % tmp % path);
}
del.cancel();
}
bool LocalBinaryCacheStore::fileExists(const std::string& path) {
return pathExists(binaryCacheDir + "/" + path);
}
void LocalBinaryCacheStore::upsertFile(const std::string& path,
const std::string& data,
const std::string& mimeType) {
atomicWrite(binaryCacheDir + "/" + path, data);
}
static RegisterStoreImplementation regStore(
[](const std::string& uri,
const Store::Params& params) -> std::shared_ptr<Store> {
if (getEnv("_NIX_FORCE_HTTP_BINARY_CACHE_STORE") == "1" ||
std::string(uri, 0, 7) != "file://") {
return nullptr;
}
auto store =
std::make_shared<LocalBinaryCacheStore>(params, std::string(uri, 7));
store->init();
return store;
});
} // namespace nix