diff options
Diffstat (limited to 'third_party/nix/src/libstore/nar-accessor.cc')
-rw-r--r-- | third_party/nix/src/libstore/nar-accessor.cc | 268 |
1 files changed, 0 insertions, 268 deletions
diff --git a/third_party/nix/src/libstore/nar-accessor.cc b/third_party/nix/src/libstore/nar-accessor.cc deleted file mode 100644 index cfd3d50b32bc..000000000000 --- a/third_party/nix/src/libstore/nar-accessor.cc +++ /dev/null @@ -1,268 +0,0 @@ -#include "libstore/nar-accessor.hh" - -#include <algorithm> -#include <map> -#include <nlohmann/json.hpp> -#include <stack> -#include <utility> - -#include "libutil/archive.hh" -#include "libutil/json.hh" - -namespace nix { - -struct NarMember { - FSAccessor::Type type = FSAccessor::Type::tMissing; - - bool isExecutable = false; - - /* If this is a regular file, position of the contents of this - file in the NAR. */ - size_t start = 0, size = 0; - - std::string target; - - /* If this is a directory, all the children of the directory. */ - std::map<std::string, NarMember> children; -}; - -struct NarAccessor : public FSAccessor { - std::shared_ptr<const std::string> nar; - - GetNarBytes getNarBytes; - - NarMember root; - - struct NarIndexer : ParseSink, StringSource { - NarAccessor& acc; - - std::stack<NarMember*> parents; - - std::string currentStart; - bool isExec = false; - - NarIndexer(NarAccessor& acc, const std::string& nar) - : StringSource(nar), acc(acc) {} - - void createMember(const Path& path, NarMember member) { - size_t level = std::count(path.begin(), path.end(), '/'); - while (parents.size() > level) { - parents.pop(); - } - - if (parents.empty()) { - acc.root = std::move(member); - parents.push(&acc.root); - } else { - if (parents.top()->type != FSAccessor::Type::tDirectory) { - throw Error("NAR file missing parent directory of path '%s'", path); - } - auto result = parents.top()->children.emplace(baseNameOf(path), - std::move(member)); - parents.push(&result.first->second); - } - } - - void createDirectory(const Path& path) override { - createMember(path, {FSAccessor::Type::tDirectory, false, 0, 0}); - } - - void createRegularFile(const Path& path) override { - createMember(path, {FSAccessor::Type::tRegular, false, 0, 0}); - } - - void isExecutable() override { parents.top()->isExecutable = true; } - - void preallocateContents(unsigned long long size) override { - currentStart = std::string(s, pos, 16); - assert(size <= std::numeric_limits<size_t>::max()); - parents.top()->size = static_cast<size_t>(size); - parents.top()->start = pos; - } - - void receiveContents(unsigned char* data, unsigned int len) override { - // Sanity check - if (!currentStart.empty()) { - assert(len < 16 || currentStart == std::string((char*)data, 16)); - currentStart.clear(); - } - } - - void createSymlink(const Path& path, const std::string& target) override { - createMember(path, - NarMember{FSAccessor::Type::tSymlink, false, 0, 0, target}); - } - }; - - explicit NarAccessor(const ref<const std::string>& nar) : nar(nar) { - NarIndexer indexer(*this, *nar); - parseDump(indexer, indexer); - } - - NarAccessor(const std::string& listing, GetNarBytes getNarBytes) - : getNarBytes(std::move(getNarBytes)) { - using json = nlohmann::json; - - std::function<void(NarMember&, json&)> recurse; - - recurse = [&](NarMember& member, json& v) { - std::string type = v["type"]; - - if (type == "directory") { - member.type = FSAccessor::Type::tDirectory; - for (auto i = v["entries"].begin(); i != v["entries"].end(); ++i) { - const std::string& name = i.key(); - recurse(member.children[name], i.value()); - } - } else if (type == "regular") { - member.type = FSAccessor::Type::tRegular; - member.size = v["size"]; - member.isExecutable = v.value("executable", false); - member.start = v["narOffset"]; - } else if (type == "symlink") { - member.type = FSAccessor::Type::tSymlink; - member.target = v.value("target", ""); - } else { - return; - } - }; - - json v = json::parse(listing); - recurse(root, v); - } - - NarMember* find(const Path& path) { - Path canon = path.empty() ? "" : canonPath(path); - NarMember* current = &root; - auto end = path.end(); - for (auto it = path.begin(); it != end;) { - // because it != end, the remaining component is non-empty so we need - // a directory - if (current->type != FSAccessor::Type::tDirectory) { - return nullptr; - } - - // skip slash (canonPath above ensures that this is always a slash) - assert(*it == '/'); - it += 1; - - // lookup current component - auto next = std::find(it, end, '/'); - auto child = current->children.find(std::string(it, next)); - if (child == current->children.end()) { - return nullptr; - } - current = &child->second; - - it = next; - } - - return current; - } - - NarMember& get(const Path& path) { - auto result = find(path); - if (result == nullptr) { - throw Error("NAR file does not contain path '%1%'", path); - } - return *result; - } - - Stat stat(const Path& path) override { - auto i = find(path); - if (i == nullptr) { - return {FSAccessor::Type::tMissing, 0, false}; - } - return {i->type, i->size, i->isExecutable, i->start}; - } - - StringSet readDirectory(const Path& path) override { - auto i = get(path); - - if (i.type != FSAccessor::Type::tDirectory) { - throw Error(format("path '%1%' inside NAR file is not a directory") % - path); - } - - StringSet res; - for (auto& child : i.children) { - res.insert(child.first); - } - - return res; - } - - std::string readFile(const Path& path) override { - auto i = get(path); - if (i.type != FSAccessor::Type::tRegular) { - throw Error(format("path '%1%' inside NAR file is not a regular file") % - path); - } - - if (getNarBytes) { - return getNarBytes(i.start, i.size); - } - - assert(nar); - return std::string(*nar, i.start, i.size); - } - - std::string readLink(const Path& path) override { - auto i = get(path); - if (i.type != FSAccessor::Type::tSymlink) { - throw Error(format("path '%1%' inside NAR file is not a symlink") % path); - } - return i.target; - } -}; - -ref<FSAccessor> makeNarAccessor(ref<const std::string> nar) { - return make_ref<NarAccessor>(nar); -} - -ref<FSAccessor> makeLazyNarAccessor(const std::string& listing, - GetNarBytes getNarBytes) { - return make_ref<NarAccessor>(listing, getNarBytes); -} - -void listNar(JSONPlaceholder& res, const ref<FSAccessor>& accessor, - const Path& path, bool recurse) { - auto st = accessor->stat(path); - - auto obj = res.object(); - - switch (st.type) { - case FSAccessor::Type::tRegular: - obj.attr("type", "regular"); - obj.attr("size", st.fileSize); - if (st.isExecutable) { - obj.attr("executable", true); - } - if (st.narOffset != 0u) { - obj.attr("narOffset", st.narOffset); - } - break; - case FSAccessor::Type::tDirectory: - obj.attr("type", "directory"); - { - auto res2 = obj.object("entries"); - for (auto& name : accessor->readDirectory(path)) { - if (recurse) { - auto res3 = res2.placeholder(name); - listNar(res3, accessor, path + "/" + name, true); - } else { - res2.object(name); - } - } - } - break; - case FSAccessor::Type::tSymlink: - obj.attr("type", "symlink"); - obj.attr("target", accessor->readLink(path)); - break; - default: - throw Error("path '%s' does not exist in NAR", path); - } -} - -} // namespace nix |