diff options
Diffstat (limited to 'src/libstore/fetchers/git.cc')
| -rw-r--r-- | src/libstore/fetchers/git.cc | 452 |
1 files changed, 452 insertions, 0 deletions
diff --git a/src/libstore/fetchers/git.cc b/src/libstore/fetchers/git.cc new file mode 100644 index 000000000..9276b0993 --- /dev/null +++ b/src/libstore/fetchers/git.cc @@ -0,0 +1,452 @@ +#include "fetchers.hh" +#include "parse.hh" +#include "globals.hh" +#include "tarfile.hh" +#include "store-api.hh" +#include "regex.hh" + +#include <sys/time.h> + +#include <nlohmann/json.hpp> + +using namespace std::string_literals; + +namespace nix::fetchers { + +static Path getCacheInfoPathFor(const std::string & name, const Hash & rev) +{ + Path cacheDir = getCacheDir() + "/nix/git-revs-v2"; + std::string linkName = + name == "source" + ? rev.gitRev() + : hashString(htSHA512, name + std::string("\0"s) + rev.gitRev()).to_string(Base32, false); + return cacheDir + "/" + linkName + ".link"; +} + +static std::string readHead(const Path & path) +{ + return chomp(runProgram("git", true, { "-C", path, "rev-parse", "--abbrev-ref", "HEAD" })); +} + +static void cacheGitInfo( + Store & store, + const std::string & name, + const Tree & tree, + const Hash & rev) +{ + nlohmann::json json; + json["storePath"] = store.printStorePath(tree.storePath); + json["name"] = name; + json["rev"] = rev.gitRev(); + json["revCount"] = *tree.info.revCount; + json["lastModified"] = *tree.info.lastModified; + + auto cacheInfoPath = getCacheInfoPathFor(name, rev); + createDirs(dirOf(cacheInfoPath)); + writeFile(cacheInfoPath, json.dump()); +} + +static std::optional<std::pair<Hash, Tree>> lookupGitInfo( + ref<Store> store, + const std::string & name, + const Hash & rev) +{ + try { + auto json = nlohmann::json::parse(readFile(getCacheInfoPathFor(name, rev))); + + assert(json["name"] == name && Hash((std::string) json["rev"], htSHA1) == rev); + + auto storePath = store->parseStorePath((std::string) json["storePath"]); + + if (store->isValidPath(storePath)) { + return {{rev, Tree{ + .actualPath = store->toRealPath(storePath), + .storePath = std::move(storePath), + .info = TreeInfo { + .revCount = json["revCount"], + .lastModified = json["lastModified"], + } + }}}; + } + + } catch (SysError & e) { + if (e.errNo != ENOENT) throw; + } + + return {}; +} + +struct GitInput : Input +{ + ParsedURL url; + std::optional<std::string> ref; + std::optional<Hash> rev; + + GitInput(const ParsedURL & url) : url(url) + { } + + std::string type() const override { return "git"; } + + bool operator ==(const Input & other) const override + { + auto other2 = dynamic_cast<const GitInput *>(&other); + return + other2 + && url == other2->url + && rev == other2->rev + && ref == other2->ref; + } + + bool isImmutable() const override + { + return (bool) rev; + } + + std::optional<std::string> getRef() const override { return ref; } + + std::optional<Hash> getRev() const override { return rev; } + + std::string to_string() const override + { + ParsedURL url2(url); + if (url2.scheme != "git") url2.scheme = "git+" + url2.scheme; + if (rev) url2.query.insert_or_assign("rev", rev->gitRev()); + if (ref) url2.query.insert_or_assign("ref", *ref); + return url2.to_string(); + } + + Attrs toAttrsInternal() const override + { + Attrs attrs; + attrs.emplace("url", url.to_string()); + if (ref) + attrs.emplace("ref", *ref); + if (rev) + attrs.emplace("rev", rev->gitRev()); + return attrs; + } + + void clone(const Path & destDir) const override + { + auto [isLocal, actualUrl] = getActualUrl(); + + Strings args = {"clone"}; + + args.push_back(actualUrl); + + if (ref) { + args.push_back("--branch"); + args.push_back(*ref); + } + + if (rev) throw Error("cloning a specific revision is not implemented"); + + args.push_back(destDir); + + runProgram("git", true, args); + } + + std::shared_ptr<const Input> applyOverrides( + std::optional<std::string> ref, + std::optional<Hash> rev) const override + { + if (!ref && !rev) return shared_from_this(); + + auto res = std::make_shared<GitInput>(*this); + + if (ref) res->ref = ref; + if (rev) res->rev = rev; + + if (!res->ref && res->rev) + throw Error("Git input '%s' has a commit hash but no branch/tag name", res->to_string()); + + return res; + } + + std::optional<Path> getSourcePath() const override + { + if (url.scheme == "file" && !ref && !rev) + return url.path; + return {}; + } + void markChangedFile(std::string_view file, std::optional<std::string> commitMsg) const override + { + auto sourcePath = getSourcePath(); + assert(sourcePath); + + runProgram("git", true, + { "-C", *sourcePath, "add", "--force", "--intent-to-add", std::string(file) }); + + if (commitMsg) + runProgram("git", true, + { "-C", *sourcePath, "commit", std::string(file), "-m", *commitMsg }); + } + + std::pair<bool, std::string> getActualUrl() const + { + // Don't clone file:// URIs (but otherwise treat them the + // same as remote URIs, i.e. don't use the working tree or + // HEAD). + static bool forceHttp = getEnv("_NIX_FORCE_HTTP") == "1"; // for testing + bool isLocal = url.scheme == "file" && !forceHttp; + return {isLocal, isLocal ? url.path : url.base}; + } + + std::pair<Tree, std::shared_ptr<const Input>> fetchTreeInternal(nix::ref<Store> store) const override + { + auto name = "source"; + + auto input = std::make_shared<GitInput>(*this); + + assert(!rev || rev->type == htSHA1); + + if (rev) { + if (auto tree = lookupGitInfo(store, name, *rev)) { + input->rev = tree->first; + return {std::move(tree->second), input}; + } + } + + auto [isLocal, actualUrl_] = getActualUrl(); + auto actualUrl = actualUrl_; // work around clang bug + + // If this is a local directory and no ref or revision is + // given, then allow the use of an unclean working tree. + if (!input->ref && !input->rev && isLocal) { + bool clean = false; + + /* Check whether this repo has any commits. There are + probably better ways to do this. */ + auto gitDir = actualUrl + "/.git"; + auto commonGitDir = chomp(runProgram( + "git", + true, + { "-C", actualUrl, "rev-parse", "--git-common-dir" } + )); + if (commonGitDir != ".git") + gitDir = commonGitDir; + + bool haveCommits = !readDirectory(gitDir + "/refs/heads").empty(); + + try { + if (haveCommits) { + runProgram("git", true, { "-C", actualUrl, "diff-index", "--quiet", "HEAD", "--" }); + clean = true; + } + } catch (ExecError & e) { + if (!WIFEXITED(e.status) || WEXITSTATUS(e.status) != 1) throw; + } + + if (!clean) { + + /* This is an unclean working tree. So copy all tracked files. */ + + if (!settings.allowDirty) + throw Error("Git tree '%s' is dirty", actualUrl); + + if (settings.warnDirty) + warn("Git tree '%s' is dirty", actualUrl); + + auto files = tokenizeString<std::set<std::string>>( + runProgram("git", true, { "-C", actualUrl, "ls-files", "-z" }), "\0"s); + + PathFilter filter = [&](const Path & p) -> bool { + assert(hasPrefix(p, actualUrl)); + std::string file(p, actualUrl.size() + 1); + + auto st = lstat(p); + + if (S_ISDIR(st.st_mode)) { + auto prefix = file + "/"; + auto i = files.lower_bound(prefix); + return i != files.end() && hasPrefix(*i, prefix); + } + + return files.count(file); + }; + + auto storePath = store->addToStore("source", actualUrl, true, htSHA256, filter); + + auto tree = Tree { + .actualPath = store->printStorePath(storePath), + .storePath = std::move(storePath), + .info = TreeInfo { + .revCount = haveCommits ? std::stoull(runProgram("git", true, { "-C", actualUrl, "rev-list", "--count", "HEAD" })) : 0, + // FIXME: maybe we should use the timestamp of the last + // modified dirty file? + .lastModified = haveCommits ? std::stoull(runProgram("git", true, { "-C", actualUrl, "log", "-1", "--format=%ct", "HEAD" })) : 0, + } + }; + + return {std::move(tree), input}; + } + } + + if (!input->ref) input->ref = isLocal ? readHead(actualUrl) : "master"; + + Path repoDir; + + if (isLocal) { + + if (!input->rev) + input->rev = Hash(chomp(runProgram("git", true, { "-C", actualUrl, "rev-parse", *input->ref })), htSHA1); + + repoDir = actualUrl; + + } else { + + Path cacheDir = getCacheDir() + "/nix/gitv3/" + hashString(htSHA256, actualUrl).to_string(Base32, false); + repoDir = cacheDir; + + if (!pathExists(cacheDir)) { + createDirs(dirOf(cacheDir)); + runProgram("git", true, { "init", "--bare", repoDir }); + } + + Path localRefFile = + input->ref->compare(0, 5, "refs/") == 0 + ? cacheDir + "/" + *input->ref + : cacheDir + "/refs/heads/" + *input->ref; + + bool doFetch; + time_t now = time(0); + + /* If a rev was specified, we need to fetch if it's not in the + repo. */ + if (input->rev) { + try { + runProgram("git", true, { "-C", repoDir, "cat-file", "-e", input->rev->gitRev() }); + doFetch = false; + } catch (ExecError & e) { + if (WIFEXITED(e.status)) { + doFetch = true; + } else { + throw; + } + } + } else { + /* If the local ref is older than ‘tarball-ttl’ seconds, do a + git fetch to update the local ref to the remote ref. */ + struct stat st; + doFetch = stat(localRefFile.c_str(), &st) != 0 || + (uint64_t) st.st_mtime + settings.tarballTtl <= (uint64_t) now; + } + + if (doFetch) { + Activity act(*logger, lvlTalkative, actUnknown, fmt("fetching Git repository '%s'", actualUrl)); + + // FIXME: git stderr messes up our progress indicator, so + // we're using --quiet for now. Should process its stderr. + try { + runProgram("git", true, { "-C", repoDir, "fetch", "--quiet", "--force", "--", actualUrl, fmt("%s:%s", *input->ref, *input->ref) }); + } catch (Error & e) { + if (!pathExists(localRefFile)) throw; + warn("could not update local clone of Git repository '%s'; continuing with the most recent version", actualUrl); + } + + struct timeval times[2]; + times[0].tv_sec = now; + times[0].tv_usec = 0; + times[1].tv_sec = now; + times[1].tv_usec = 0; + + utimes(localRefFile.c_str(), times); + } + + if (!input->rev) + input->rev = Hash(chomp(readFile(localRefFile)), htSHA1); + } + + if (auto tree = lookupGitInfo(store, name, *input->rev)) { + assert(*input->rev == tree->first); + return {std::move(tree->second), input}; + } + + // FIXME: check whether rev is an ancestor of ref. + + printTalkative("using revision %s of repo '%s'", input->rev->gitRev(), actualUrl); + + // FIXME: should pipe this, or find some better way to extract a + // revision. + auto source = sinkToSource([&](Sink & sink) { + RunOptions gitOptions("git", { "-C", repoDir, "archive", input->rev->gitRev() }); + gitOptions.standardOut = &sink; + runProgram2(gitOptions); + }); + + Path tmpDir = createTempDir(); + AutoDelete delTmpDir(tmpDir, true); + + unpackTarfile(*source, tmpDir); + + auto storePath = store->addToStore(name, tmpDir); + auto revCount = std::stoull(runProgram("git", true, { "-C", repoDir, "rev-list", "--count", input->rev->gitRev() })); + auto lastModified = std::stoull(runProgram("git", true, { "-C", repoDir, "log", "-1", "--format=%ct", input->rev->gitRev() })); + + auto tree = Tree { + .actualPath = store->toRealPath(storePath), + .storePath = std::move(storePath), + .info = TreeInfo { + .revCount = revCount, + .lastModified = lastModified + } + }; + + cacheGitInfo(*store, name, tree, *input->rev); + + return {std::move(tree), input}; + } +}; + +struct GitInputScheme : InputScheme +{ + std::unique_ptr<Input> inputFromURL(const ParsedURL & url) override + { + if (url.scheme != "git" && + url.scheme != "git+http" && + url.scheme != "git+https" && + url.scheme != "git+ssh" && + url.scheme != "git+file") return nullptr; + + auto url2(url); + if (hasPrefix(url2.scheme, "git+")) url2.scheme = std::string(url2.scheme, 4); + url2.query.clear(); + + Input::Attrs attrs; + attrs.emplace("type", "git"); + + for (auto &[name, value] : url.query) { + if (name == "rev" || name == "ref") + attrs.emplace(name, value); + else + url2.query.emplace(name, value); + } + + attrs.emplace("url", url2.to_string()); + + return inputFromAttrs(attrs); + } + + std::unique_ptr<Input> inputFromAttrs(const Input::Attrs & attrs) override + { + if (maybeGetStrAttr(attrs, "type") != "git") return {}; + + for (auto & [name, value] : attrs) + if (name != "type" && name != "url" && name != "ref" && name != "rev") + throw Error("unsupported Git input attribute '%s'", name); + + auto input = std::make_unique<GitInput>(parseURL(getStrAttr(attrs, "url"))); + if (auto ref = maybeGetStrAttr(attrs, "ref")) { + if (!std::regex_match(*ref, refRegex)) + throw BadURL("invalid Git branch/tag name '%s'", *ref); + input->ref = *ref; + } + if (auto rev = maybeGetStrAttr(attrs, "rev")) + input->rev = Hash(*rev, htSHA1); + return input; + } +}; + +static auto r1 = OnStartup([] { registerInputScheme(std::make_unique<GitInputScheme>()); }); + +} |