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|
#include "lix/libutil/archive.hh"
#include "lix/libutil/async-io.hh"
#include "lix/libutil/async.hh"
#include "lix/libutil/c-calls.hh"
#include "lix/libutil/error.hh"
#include "lix/libfetchers/fetchers.hh"
#include "lix/libfetchers/cache.hh"
#include "lix/libstore/globals.hh"
#include "lix/libfetchers/builtin-fetchers.hh"
#include "lix/libutil/processes.hh"
#include "lix/libutil/result.hh"
#include "lix/libutil/tarfile.hh"
#include "lix/libstore/store-api.hh"
#include "lix/libstore/temporary-dir.hh"
#include "lix/libutil/url-parts.hh"
#include "lix/libstore/pathlocks.hh"
#include "lix/libutil/users.hh"
#include "lix/libutil/git.hh"
#include "lix/libutil/logging.hh"
#include "lix/libutil/finally.hh"
#include "lix/libfetchers/fetch-settings.hh"
#include <optional>
#include <regex>
#include <string.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <unistd.h>
using namespace std::string_literals;
namespace nix::fetchers {
namespace {
// Explicit initial branch of our bare repo to suppress warnings from new version of git.
// The value itself does not matter, since we always fetch a specific revision or branch.
// It is set with `-c init.defaultBranch=` instead of `--initial-branch=` to stay compatible with
// old version of git, which will ignore unrecognized `-c` options.
const std::string gitInitialBranch = "__nix_dummy_branch";
bool isCacheFileWithinTtl(time_t now, const struct stat & st)
{
return st.st_mtime + settings.tarballTtl > now;
}
bool touchCacheFile(const Path & path, time_t touch_time)
{
struct timeval times[2];
times[0].tv_sec = touch_time;
times[0].tv_usec = 0;
times[1].tv_sec = touch_time;
times[1].tv_usec = 0;
return sys::lutimes(path, times) == 0;
}
Path getCachePath(std::string_view key)
{
return getCacheDir() + "/nix/gitv3/"
+ hashString(HashType::SHA256, key).to_string(HashFormat::Base32, false);
}
// Returns the name of the HEAD branch.
//
// Returns the head branch name as reported by git ls-remote --symref, e.g., if
// ls-remote returns the output below, "main" is returned based on the ref line.
//
// ref: refs/heads/main HEAD
// ...
static kj::Promise<Result<std::optional<std::string>>> readHead(const Path & path)
try {
auto output = TRY_AWAIT(runProgram(
"git",
true,
// FIXME: use 'HEAD' to avoid returning all refs
{"ls-remote", "--symref", path},
true
));
std::string_view line = output;
line = line.substr(0, line.find("\n"));
if (const auto parseResult = git::parseLsRemoteLine(line)) {
switch (parseResult->kind) {
case git::LsRemoteRefLine::Kind::Symbolic:
debug("resolved HEAD ref '%s' for repo '%s'", parseResult->target, path);
break;
case git::LsRemoteRefLine::Kind::Object:
debug("resolved HEAD rev '%s' for repo '%s'", parseResult->target, path);
break;
}
co_return parseResult->target;
}
co_return std::nullopt;
} catch (ExecError &) {
co_return std::nullopt;
} catch (...) {
co_return result::current_exception();
}
// Persist the HEAD ref from the remote repo in the local cached repo.
static kj::Promise<Result<bool>>
storeCachedHead(const std::string & actualUrl, const std::string & headRef)
try {
Path cacheDir = getCachePath(actualUrl);
try {
TRY_AWAIT(runProgram(
"git", true, {"-C", cacheDir, "--git-dir", ".", "symbolic-ref", "--", "HEAD", headRef}
));
} catch (ExecError & e) {
if (!WIFEXITED(e.status)) {
throw;
}
co_return false;
}
/* No need to touch refs/HEAD, because `git symbolic-ref` updates the mtime. */
co_return true;
} catch (...) {
co_return result::current_exception();
}
static kj::Promise<Result<std::optional<std::string>>> readHeadCached(const std::string & actualUrl)
try {
// Create a cache path to store the branch of the HEAD ref. Append something
// in front of the URL to prevent collision with the repository itself.
Path cacheDir = getCachePath(actualUrl);
Path headRefFile = cacheDir + "/HEAD";
time_t now = time(0);
struct stat st;
std::optional<std::string> cachedRef;
if (sys::stat(headRefFile, &st) == 0) {
cachedRef = TRY_AWAIT(readHead(cacheDir));
if (cachedRef != std::nullopt &&
*cachedRef != gitInitialBranch &&
isCacheFileWithinTtl(now, st))
{
debug("using cached HEAD ref '%s' for repo '%s'", *cachedRef, actualUrl);
co_return cachedRef;
}
}
auto ref = TRY_AWAIT(readHead(actualUrl));
if (ref) {
co_return ref;
}
if (cachedRef) {
// If the cached git ref is expired in fetch() below, and the 'git fetch'
// fails, it falls back to continuing with the most recent version.
// This function must behave the same way, so we return the expired
// cached ref here.
printTaggedWarning(
"could not get HEAD ref for repository '%s'; using expired cached ref '%s'",
actualUrl,
*cachedRef
);
co_return cachedRef;
}
co_return std::nullopt;
} catch (...) {
co_return result::current_exception();
}
bool isNotDotGitDirectory(const Path & path)
{
return baseNameOf(path) != ".git";
}
struct WorkdirInfo
{
bool clean = false;
bool hasHead = false;
};
// Returns whether a git workdir is clean and has commits.
static kj::Promise<Result<WorkdirInfo>> getWorkdirInfo(const Input & input, const Path & workdir)
try {
const bool submodules = maybeGetBoolAttr(input.attrs, "submodules").value_or(false);
std::string gitDir(".git");
auto env = getEnv();
// Set LC_ALL to C: because we rely on the error messages from git rev-parse to determine what went wrong
// that way unknown errors can lead to a failure instead of continuing through the wrong code path
env["LC_ALL"] = "C";
/* Check whether HEAD points to something that looks like a commit,
since that is the refrence we want to use later on. */
auto result = TRY_AWAIT(runProgram(RunOptions{
.program = "git",
.args =
{"-C",
workdir,
"--git-dir",
gitDir,
"rev-parse",
"--verify",
"--no-revs",
"HEAD^{commit}"},
.environment = env,
.redirections = {{.dup = STDERR_FILENO, .from = STDOUT_FILENO}},
}));
auto exitCode = WEXITSTATUS(result.first);
auto errorMessage = result.second;
if (errorMessage.find("fatal: not a git repository") != std::string::npos) {
throw Error("'%s' is not a Git repository", workdir);
} else if (errorMessage.find("fatal: Needed a single revision") != std::string::npos) {
// indicates that the repo does not have any commits
// we want to proceed and will consider it dirty later
} else if (exitCode != 0) {
// any other errors should lead to a failure
throw Error("getting the HEAD of the Git tree '%s' failed with exit code %d:\n%s", workdir, exitCode, errorMessage);
}
bool clean = false;
bool hasHead = exitCode == 0;
try {
if (hasHead) {
// Using git diff is preferrable over lower-level operations here,
// because its conceptually simpler and we only need the exit code anyways.
auto gitDiffOpts = Strings({ "-C", workdir, "--git-dir", gitDir, "diff", "HEAD", "--quiet"});
if (!submodules) {
// Changes in submodules should only make the tree dirty
// when those submodules will be copied as well.
gitDiffOpts.emplace_back("--ignore-submodules");
}
gitDiffOpts.emplace_back("--");
TRY_AWAIT(runProgram("git", true, gitDiffOpts));
clean = true;
}
} catch (ExecError & e) {
if (!WIFEXITED(e.status) || WEXITSTATUS(e.status) != 1) throw;
}
co_return WorkdirInfo{.clean = clean, .hasHead = hasHead};
} catch (...) {
co_return result::current_exception();
}
static kj::Promise<Result<std::pair<StorePath, Input>>> fetchFromWorkdir(ref<Store> store, Input & input, const Path & workdir, const WorkdirInfo & workdirInfo)
try {
const bool submodules = maybeGetBoolAttr(input.attrs, "submodules").value_or(false);
auto gitDir = ".git";
if (!fetchSettings.allowDirty)
throw Error("Git tree '%s' is dirty", workdir);
if (fetchSettings.warnDirty) {
printTaggedWarning("Git tree '%s' is dirty", workdir);
}
auto gitOpts = Strings({ "-C", workdir, "--git-dir", gitDir, "ls-files", "-z" });
if (submodules)
gitOpts.emplace_back("--recurse-submodules");
auto files =
tokenizeString<std::set<std::string>>(TRY_AWAIT(runProgram("git", true, gitOpts)), "\0"s);
Path actualPath(absPath(workdir));
PathFilter filter = [&](const Path & p) -> bool {
assert(p.starts_with(actualPath));
std::string file(p, actualPath.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() && (*i).starts_with(prefix)) || files.count(file);
}
return files.count(file);
};
auto storePath = TRY_AWAIT(store->addToStoreRecursive(
input.getName(), *prepareDump(actualPath, filter), HashType::SHA256
));
// FIXME: maybe we should use the timestamp of the last
// modified dirty file?
input.attrs.insert_or_assign(
"lastModified",
workdirInfo.hasHead ? std::stoull(TRY_AWAIT(runProgram(
"git",
true,
{"-C",
actualPath,
"--git-dir",
gitDir,
"log",
"-1",
"--format=%ct",
"--no-show-signature",
"HEAD"}
)))
: 0
);
if (workdirInfo.hasHead) {
input.attrs.insert_or_assign(
"dirtyRev",
chomp(TRY_AWAIT(runProgram(
"git",
true,
{"-C", actualPath, "--git-dir", gitDir, "rev-parse", "--verify", "HEAD"}
))) + "-dirty"
);
input.attrs.insert_or_assign(
"dirtyShortRev",
chomp(TRY_AWAIT(runProgram(
"git",
true,
{"-C", actualPath, "--git-dir", gitDir, "rev-parse", "--verify", "--short", "HEAD"}
))) + "-dirty"
);
}
co_return {std::move(storePath), input};
} catch (...) {
co_return result::current_exception();
}
} // end namespace
static std::optional<Path> resolveRefToCachePath(
Input & input,
const Path & cacheDir,
std::vector<Path> & gitRefFileCandidates,
std::function<bool(const Path&)> condition)
{
if (input.getRef()->starts_with("refs/")) {
Path fullpath = cacheDir + "/" + *input.getRef();
if (condition(fullpath)) {
return fullpath;
}
}
for (auto & candidate : gitRefFileCandidates) {
if (condition(candidate)) {
return candidate;
}
}
return std::nullopt;
}
static const std::set<std::string> allowedGitAttrs = {
"allRefs",
"dirtyRev",
"dirtyShortRev",
"lastModified",
"name",
"ref",
"rev",
"revCount",
"shallow",
"submodules",
"url",
};
struct GitInputScheme : InputScheme
{
std::string schemeType() const override { return "git"; }
const std::set<std::string> & allowedAttrs() const override {
return allowedGitAttrs;
}
std::optional<Input> inputFromURL(const ParsedURL & url, bool requireTree) const override
{
if (url.scheme != "git" &&
url.scheme != "git+http" &&
url.scheme != "git+https" &&
url.scheme != "git+ssh" &&
url.scheme != "git+file") return {};
auto url2(url);
if (url2.scheme.starts_with("git+")) url2.scheme = std::string(url2.scheme, 4);
url2.query.clear();
Attrs attrs;
attrs.emplace("type", "git");
attrs.emplace("url", url2.to_string());
emplaceURLQueryIntoAttrs(
url,
attrs,
{"lastModified", "revCount"},
{"shallow", "submodules", "allRefs"}
);
return inputFromAttrs(attrs);
}
Attrs preprocessAttrs(const Attrs & attrs) const override {
parseURL(getStrAttr(attrs, "url"));
maybeGetBoolAttr(attrs, "shallow");
maybeGetBoolAttr(attrs, "submodules");
maybeGetBoolAttr(attrs, "allRefs");
if (auto ref = maybeGetStrAttr(attrs, "ref")) {
if (std::regex_search(*ref, badGitRefRegex))
throw BadURL("invalid Git branch/tag name '%s'", *ref);
}
return attrs;
}
ParsedURL toURL(const Input & input) const override
{
auto url = parseURL(getStrAttr(input.attrs, "url"));
if (url.scheme != "git") url.scheme = "git+" + url.scheme;
if (auto rev = input.getRev()) url.query.insert_or_assign("rev", rev->gitRev());
if (auto ref = input.getRef()) url.query.insert_or_assign("ref", *ref);
if (maybeGetBoolAttr(input.attrs, "shallow").value_or(false))
url.query.insert_or_assign("shallow", "1");
return url;
}
bool hasAllInfo(const Input & input) const override
{
bool maybeDirty = !input.getRef();
bool shallow = maybeGetBoolAttr(input.attrs, "shallow").value_or(false);
return
maybeGetIntAttr(input.attrs, "lastModified")
&& (shallow || maybeDirty || maybeGetIntAttr(input.attrs, "revCount"));
}
Input applyOverrides(
const Input & input,
std::optional<std::string> ref,
std::optional<Hash> rev) const override
{
auto res(input);
if (rev) res.attrs.insert_or_assign("rev", rev->gitRev());
if (ref) res.attrs.insert_or_assign("ref", *ref);
if (!res.getRef() && res.getRev())
throw Error("Git input '%s' has a commit hash but no branch/tag name", res.to_string());
return res;
}
kj::Promise<Result<void>> clone(const Input & input, const Path & destDir) const override
try {
auto [isLocal, actualUrl] = getActualUrl(input);
Strings args = {"clone"};
args.push_back(actualUrl);
if (auto ref = input.getRef()) {
args.push_back("--branch");
args.push_back(*ref);
}
if (input.getRev()) throw UnimplementedError("cloning a specific revision is not implemented");
args.push_back(destDir);
TRY_AWAIT(runProgram("git", true, args, true));
co_return result::success();
} catch (...) {
co_return result::current_exception();
}
std::optional<Path> getSourcePath(const Input & input) const override
{
auto url = parseURL(getStrAttr(input.attrs, "url"));
if (url.scheme == "file" && !input.getRef() && !input.getRev())
return url.path;
return {};
}
kj::Promise<Result<void>> putFile(
const Input & input,
const CanonPath & path,
std::string_view contents,
std::optional<std::string> commitMsg
) const override
try {
auto root = getSourcePath(input);
if (!root)
throw Error("cannot commit '%s' to Git repository '%s' because it's not a working tree", path, input.to_string());
writeFile((CanonPath(*root) + path).abs(), contents);
auto gitDir = ".git";
auto result = TRY_AWAIT(runProgram(RunOptions{
.program = "git",
.args =
{"-C",
*root,
"--git-dir",
gitDir,
"check-ignore",
"--quiet",
std::string(path.rel())},
}));
auto exitCode = WEXITSTATUS(result.first);
if (exitCode != 0) {
// The path is not `.gitignore`d, we can add the file.
TRY_AWAIT(runProgram(
"git",
true,
{"-C",
*root,
"--git-dir",
gitDir,
"add",
"--intent-to-add",
"--",
std::string(path.rel())}
));
if (commitMsg) {
auto [_fd, msgPath] = createTempFile("nix-msg");
AutoDelete const _delete{msgPath};
writeFile(msgPath, *commitMsg);
TRY_AWAIT(runProgram(
"git",
true,
{"-C",
*root,
"--git-dir",
gitDir,
"commit",
std::string(path.rel()),
"-F",
msgPath},
true
));
}
}
co_return result::success();
} catch (...) {
co_return result::current_exception();
}
std::pair<bool, std::string> getActualUrl(const Input & input) const
{
// file:// URIs are normally not cloned (but otherwise treated the
// same as remote URIs, i.e. we don't use the working tree or
// HEAD). Exception: If _NIX_FORCE_HTTP is set, or the repo is a bare git
// repo, treat as a remote URI to force a clone.
static bool forceHttp = getEnv("_NIX_FORCE_HTTP") == "1"; // for testing
auto url = parseURL(getStrAttr(input.attrs, "url"));
bool isBareRepository = url.scheme == "file" && !pathExists(url.path + "/.git");
bool isLocal = url.scheme == "file" && !forceHttp && !isBareRepository;
return {isLocal, isLocal ? url.path : url.base};
}
kj::Promise<Result<std::pair<StorePath, Input>>>
fetch(ref<Store> store, const Input & _input) override
try {
Input input(_input);
auto gitDir = ".git";
std::string name = input.getName();
bool shallow = maybeGetBoolAttr(input.attrs, "shallow").value_or(false);
bool submodules = maybeGetBoolAttr(input.attrs, "submodules").value_or(false);
bool allRefs = maybeGetBoolAttr(input.attrs, "allRefs").value_or(false);
std::string cacheType = "git";
if (shallow) cacheType += "-shallow";
if (submodules) cacheType += "-submodules";
if (allRefs) cacheType += "-all-refs";
auto checkHashType = [&](const std::optional<Hash> & hash)
{
if (hash.has_value() && !(hash->type == HashType::SHA1 || hash->type == HashType::SHA256))
throw Error(
"Hash '%s' is not supported by Git. Supported types are sha1 and sha256.",
hash->to_string(HashFormat::Base16)
);
};
auto getLockedAttrs = [&]()
{
checkHashType(input.getRev());
return Attrs({
{"type", cacheType},
{"name", name},
{"rev", input.getRev()->gitRev()},
});
};
auto makeResult = [&](const Attrs & infoAttrs, StorePath && storePath)
-> std::pair<StorePath, Input>
{
assert(input.getRev());
assert(!_input.getRev() || _input.getRev() == input.getRev());
if (!shallow)
input.attrs.insert_or_assign("revCount", getIntAttr(infoAttrs, "revCount"));
input.attrs.insert_or_assign("lastModified", getIntAttr(infoAttrs, "lastModified"));
return {std::move(storePath), input};
};
if (input.getRev()) {
if (auto res = TRY_AWAIT(getCache()->lookup(store, getLockedAttrs())))
co_return makeResult(res->first, std::move(res->second));
}
auto [isLocal, actualUrl_] = getActualUrl(input);
auto actualUrl = actualUrl_; // work around clang bug
/* If this is a local directory and no ref or revision is given,
allow fetching directly from a dirty workdir. */
if (!input.getRef() && !input.getRev() && isLocal) {
auto workdirInfo = TRY_AWAIT(getWorkdirInfo(input, actualUrl));
if (!workdirInfo.clean) {
co_return TRY_AWAIT(fetchFromWorkdir(store, input, actualUrl, workdirInfo));
}
}
Attrs unlockedAttrs({
{"type", cacheType},
{"name", name},
{"url", actualUrl},
});
Path repoDir;
if (isLocal) {
if (!input.getRef()) {
auto head = TRY_AWAIT(readHead(actualUrl));
if (!head) {
printTaggedWarning(
"could not read HEAD ref from repo at '%s', using 'master'", actualUrl
);
head = "master";
}
input.attrs.insert_or_assign("ref", *head);
unlockedAttrs.insert_or_assign("ref", *head);
}
if (!input.getRev())
input.attrs.insert_or_assign(
"rev",
Hash::parseAny(
chomp(TRY_AWAIT(runProgram(
"git",
true,
{"-C", actualUrl, "--git-dir", gitDir, "rev-parse", *input.getRef()}
))),
HashType::SHA1
)
.gitRev()
);
repoDir = actualUrl;
} else {
const bool useHeadRef = !input.getRef();
if (useHeadRef) {
auto head = TRY_AWAIT(readHeadCached(actualUrl));
if (!head) {
printTaggedWarning(
"could not read HEAD ref from repo at '%s', using 'master'", actualUrl
);
head = "master";
}
input.attrs.insert_or_assign("ref", *head);
unlockedAttrs.insert_or_assign("ref", *head);
} else {
if (!input.getRev()) {
unlockedAttrs.insert_or_assign("ref", input.getRef().value());
}
}
if (auto res = TRY_AWAIT(getCache()->lookup(store, unlockedAttrs))) {
auto rev2 = Hash::parseAny(getStrAttr(res->first, "rev"), HashType::SHA1);
if (!input.getRev() || input.getRev() == rev2) {
input.attrs.insert_or_assign("rev", rev2.gitRev());
co_return makeResult(res->first, std::move(res->second));
}
}
Path cacheDir = getCachePath(actualUrl);
repoDir = cacheDir;
gitDir = ".";
createDirs(dirOf(cacheDir));
PathLock cacheDirLock = TRY_AWAIT(lockPathAsync(cacheDir + ".lock"));
if (!pathExists(cacheDir)) {
TRY_AWAIT(runProgram(
"git",
true,
{"-c", "init.defaultBranch=" + gitInitialBranch, "init", "--bare", repoDir}
));
}
std::vector<Path> gitRefFileCandidates;
for (auto & infix : {"", "tags/", "heads/"}) {
Path p = cacheDir + "/refs/" + infix + *input.getRef();
gitRefFileCandidates.push_back(p);
}
Path localRefFile;
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.getRev()) {
try {
TRY_AWAIT(runProgram(
"git",
true,
{"-C",
repoDir,
"--git-dir",
gitDir,
"cat-file",
"-e",
input.getRev()->gitRev()}
));
doFetch = false;
} catch (ExecError & e) {
if (WIFEXITED(e.status)) {
doFetch = true;
} else {
throw;
}
}
} else {
if (allRefs) {
doFetch = true;
} else {
std::function<bool(const Path&)> condition;
condition = [&now](const Path & path) {
/* 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;
return sys::stat(path, &st) == 0 && isCacheFileWithinTtl(now, st);
};
if (auto result = resolveRefToCachePath(
input,
cacheDir,
gitRefFileCandidates,
condition
)) {
localRefFile = *result;
doFetch = false;
} else {
doFetch = true;
}
}
}
// When having to fetch, we don't know `localRefFile` yet.
// Because git needs to figure out what we're fetching
// (i.e. is it a rev? a branch? a tag?)
if (doFetch) {
auto act = logger->startActivity(
lvlTalkative, actUnknown, fmt("fetching Git repository '%s'", actualUrl)
);
auto ref = input.getRef();
std::string fetchRef;
if (allRefs) {
fetchRef = "refs/*";
} else if (
ref->starts_with("refs/")
|| *ref == "HEAD"
|| std::regex_match(*ref, revRegex))
{
fetchRef = *ref;
} else {
fetchRef = "refs/*/" + *ref;
}
try {
Finally finally([&]() {
if (auto p = resolveRefToCachePath(
input,
cacheDir,
gitRefFileCandidates,
pathExists
)) {
localRefFile = *p;
}
});
// FIXME: git stderr messes up our progress indicator, so
// we're using --quiet for now. Should process its stderr.
TRY_AWAIT(runProgram(
"git",
true,
{"-C",
repoDir,
"--git-dir",
gitDir,
"fetch",
"--quiet",
"--force",
"--",
actualUrl,
fmt("%s:%s", fetchRef, fetchRef)},
true
));
} catch (Error & e) {
if (!pathExists(localRefFile)) throw;
printTaggedWarning(
"could not update local clone of Git repository '%s'; continuing with the "
"most recent version",
actualUrl
);
}
if (!touchCacheFile(localRefFile, now))
printTaggedWarning(
"could not update mtime for file '%s': %s", localRefFile, strerror(errno)
);
if (useHeadRef && !TRY_AWAIT(storeCachedHead(actualUrl, *input.getRef()))) {
printTaggedWarning(
"could not update cached head '%s' for '%s'", *input.getRef(), actualUrl
);
}
}
if (!input.getRev()) {
auto rev = chomp(TRY_AWAIT(runProgram(
"git",
true,
{"-C", repoDir, "--git-dir", gitDir, "rev-list", "--max-count=1", *input.getRef()}
)));
input.attrs.insert_or_assign("rev", rev);
}
// cache dir lock is removed at scope end; we will only use read-only operations on specific revisions in the remainder
}
bool isShallow =
chomp(TRY_AWAIT(runProgram(
"git",
true,
{"-C", repoDir, "--git-dir", gitDir, "rev-parse", "--is-shallow-repository"}
)))
== "true";
if (isShallow && !shallow)
throw Error("'%s' is a shallow Git repository, but shallow repositories are only allowed when `shallow = true;` is specified.", actualUrl);
// FIXME: check whether rev is an ancestor of ref.
printTalkative("using revision %s of repo '%s'", input.getRev()->gitRev(), actualUrl);
/* Now that we know the ref, check again whether we have it in
the store. */
if (auto res = TRY_AWAIT(getCache()->lookup(store, getLockedAttrs())))
co_return makeResult(res->first, std::move(res->second));
Path tmpDir = createTempDir();
AutoDelete delTmpDir(tmpDir, true);
PathFilter filter = defaultPathFilter;
auto result = TRY_AWAIT(runProgram(RunOptions{
.program = "git",
.args =
{"-C", repoDir, "--git-dir", gitDir, "cat-file", "commit", input.getRev()->gitRev()
},
.redirections = {{.dup = STDERR_FILENO, .from = STDOUT_FILENO}},
}));
if (WEXITSTATUS(result.first) == 128
&& result.second.find("bad file") != std::string::npos)
{
throw Error(
"Cannot find Git revision '%s' in ref '%s' of repository '%s'! "
"Please make sure that the " ANSI_BOLD "rev" ANSI_NORMAL " exists on the "
ANSI_BOLD "ref" ANSI_NORMAL " you've specified or add " ANSI_BOLD
"allRefs = true;" ANSI_NORMAL " to " ANSI_BOLD "fetchGit" ANSI_NORMAL ".",
input.getRev()->gitRev(),
*input.getRef(),
actualUrl
);
}
if (submodules) {
Path tmpGitDir = createTempDir();
AutoDelete delTmpGitDir(tmpGitDir, true);
TRY_AWAIT(runProgram(
"git",
true,
{"-c",
"init.defaultBranch=" + gitInitialBranch,
"init",
tmpDir,
"--separate-git-dir",
tmpGitDir}
));
{
// TODO: repoDir might lack the ref (it only checks if rev
// exists, see FIXME above) so use a big hammer and fetch
// everything to ensure we get the rev.
auto act = logger->startActivity(
lvlTalkative, actUnknown, fmt("making temporary clone of '%s'", repoDir)
);
TRY_AWAIT(runProgram(
"git",
true,
{"-C",
tmpDir,
"fetch",
"--quiet",
"--force",
"--update-head-ok",
"--",
repoDir,
"refs/*:refs/*"},
true
));
}
TRY_AWAIT(runProgram(
"git", true, {"-C", tmpDir, "checkout", "--quiet", input.getRev()->gitRev()}
));
/* Ensure that we use the correct origin for fetching
submodules. This matters for submodules with relative
URLs. */
if (isLocal) {
writeFile(tmpGitDir + "/config", readFile(repoDir + "/" + gitDir + "/config"));
/* Restore the config.bare setting we may have just
copied erroneously from the user's repo. */
TRY_AWAIT(runProgram("git", true, {"-C", tmpDir, "config", "core.bare", "false"}));
} else
TRY_AWAIT(runProgram(
"git", true, {"-C", tmpDir, "config", "remote.origin.url", actualUrl}
));
/* As an optimisation, copy the modules directory of the
source repo if it exists. */
auto modulesPath = repoDir + "/" + gitDir + "/modules";
if (pathExists(modulesPath)) {
auto act = logger->startActivity(
lvlTalkative, actUnknown, fmt("copying submodules of '%s'", actualUrl)
);
TRY_AWAIT(runProgram("cp", true, {"-R", "--", modulesPath, tmpGitDir + "/modules"})
);
}
{
auto act = logger->startActivity(
lvlTalkative, actUnknown, fmt("fetching submodules of '%s'", actualUrl)
);
TRY_AWAIT(runProgram(
"git",
true,
{"-C", tmpDir, "submodule", "--quiet", "update", "--init", "--recursive"},
true
));
}
filter = isNotDotGitDirectory;
} else {
auto proc = runProgram2({
.program = "git",
.args = { "-C", repoDir, "--git-dir", gitDir, "archive", input.getRev()->gitRev() },
.captureStdout = true,
});
Finally const _wait([&] { proc.waitAndCheck(); });
TRY_AWAIT(unpackTarfile(*proc.getStdout(), tmpDir));
}
auto storePath = TRY_AWAIT(
store->addToStoreRecursive(name, *prepareDump(tmpDir, filter), HashType::SHA256)
);
auto lastModified = std::stoull(TRY_AWAIT(runProgram(
"git",
true,
{"-C",
repoDir,
"--git-dir",
gitDir,
"log",
"-1",
"--format=%ct",
"--no-show-signature",
input.getRev()->gitRev()}
)));
Attrs infoAttrs({
{"rev", input.getRev()->gitRev()},
{"lastModified", lastModified},
});
if (!shallow)
infoAttrs.insert_or_assign(
"revCount",
std::stoull(TRY_AWAIT(runProgram(
"git",
true,
{"-C",
repoDir,
"--git-dir",
gitDir,
"rev-list",
"--count",
input.getRev()->gitRev()}
)))
);
if (!_input.getRev())
getCache()->add(
store,
unlockedAttrs,
infoAttrs,
storePath,
false);
getCache()->add(
store,
getLockedAttrs(),
infoAttrs,
storePath,
true);
co_return makeResult(infoAttrs, std::move(storePath));
} catch (...) {
co_return result::current_exception();
}
};
std::unique_ptr<InputScheme> makeGitInputScheme()
{
return std::make_unique<GitInputScheme>();
}
struct GitLockedInputScheme : GitInputScheme {
std::string schemeType() const override {
using namespace std::literals::string_literals;
return "\0git-locked"s;
}
bool hasAllInfo(const Input & input) const override {
return true;
}
};
std::unique_ptr<InputScheme> makeGitLockedInputScheme()
{
return std::make_unique<GitLockedInputScheme>();
}
}
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