nix-super/src/libfetchers/mercurial.cc
2020-07-31 01:07:59 +00:00

297 lines
10 KiB
C++

#include "fetchers.hh"
#include "cache.hh"
#include "globals.hh"
#include "tarfile.hh"
#include "store-api.hh"
#include <sys/time.h>
using namespace std::string_literals;
namespace nix::fetchers {
struct MercurialInputScheme : InputScheme
{
std::optional<Input> inputFromURL(const ParsedURL & url) override
{
if (url.scheme != "hg+http" &&
url.scheme != "hg+https" &&
url.scheme != "hg+ssh" &&
url.scheme != "hg+file") return {};
auto url2(url);
url2.scheme = std::string(url2.scheme, 3);
url2.query.clear();
Attrs attrs;
attrs.emplace("type", "hg");
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::optional<Input> inputFromAttrs(const Attrs & attrs) override
{
if (maybeGetStrAttr(attrs, "type") != "hg") return {};
for (auto & [name, value] : attrs)
if (name != "type" && name != "url" && name != "ref" && name != "rev" && name != "revCount" && name != "narHash")
throw Error("unsupported Mercurial input attribute '%s'", name);
parseURL(getStrAttr(attrs, "url"));
if (auto ref = maybeGetStrAttr(attrs, "ref")) {
if (!std::regex_match(*ref, refRegex))
throw BadURL("invalid Mercurial branch/tag name '%s'", *ref);
}
Input input;
input.attrs = attrs;
return input;
}
ParsedURL toURL(const Input & input) override
{
auto url = parseURL(getStrAttr(input.attrs, "url"));
url.scheme = "hg+" + 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);
return url;
}
bool hasAllInfo(const Input & input) override
{
// FIXME: ugly, need to distinguish between dirty and clean
// default trees.
return input.getRef() == "default" || maybeGetIntAttr(input.attrs, "revCount");
}
Input applyOverrides(
const Input & input,
std::optional<std::string> ref,
std::optional<Hash> rev) override
{
auto res(input);
if (rev) res.attrs.insert_or_assign("rev", rev->gitRev());
if (ref) res.attrs.insert_or_assign("ref", *ref);
return res;
}
std::optional<Path> getSourcePath(const Input & input) override
{
auto url = parseURL(getStrAttr(input.attrs, "url"));
if (url.scheme == "file" && !input.getRef() && !input.getRev())
return url.path;
return {};
}
void markChangedFile(const Input & input, std::string_view file, std::optional<std::string> commitMsg) override
{
auto sourcePath = getSourcePath(input);
assert(sourcePath);
// FIXME: shut up if file is already tracked.
runProgram("hg", true,
{ "add", *sourcePath + "/" + std::string(file) });
if (commitMsg)
runProgram("hg", true,
{ "commit", *sourcePath + "/" + std::string(file), "-m", *commitMsg });
}
std::pair<bool, std::string> getActualUrl(const Input & input) const
{
auto url = parseURL(getStrAttr(input.attrs, "url"));
bool isLocal = url.scheme == "file";
return {isLocal, isLocal ? url.path : url.base};
}
std::pair<Tree, Input> fetch(ref<Store> store, const Input & _input) override
{
auto name = "source";
Input input(_input);
auto [isLocal, actualUrl_] = getActualUrl(input);
auto actualUrl = actualUrl_; // work around clang bug
// FIXME: return lastModified.
// FIXME: don't clone local repositories.
if (!input.getRef() && !input.getRev() && isLocal && pathExists(actualUrl + "/.hg")) {
bool clean = runProgram("hg", true, { "status", "-R", actualUrl, "--modified", "--added", "--removed" }) == "";
if (!clean) {
/* This is an unclean working tree. So copy all tracked
files. */
if (!settings.allowDirty)
throw Error("Mercurial tree '%s' is unclean", actualUrl);
if (settings.warnDirty)
warn("Mercurial tree '%s' is unclean", actualUrl);
input.attrs.insert_or_assign("ref", chomp(runProgram("hg", true, { "branch", "-R", actualUrl })));
auto files = tokenizeString<std::set<std::string>>(
runProgram("hg", true, { "status", "-R", actualUrl, "--clean", "--modified", "--added", "--no-status", "--print0" }), "\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, FileIngestionMethod::Recursive, htSHA256, filter);
return {
Tree(store->printStorePath(storePath), std::move(storePath)),
input
};
}
}
if (!input.getRef()) input.attrs.insert_or_assign("ref", "default");
auto getImmutableAttrs = [&]()
{
return Attrs({
{"type", "hg"},
{"name", name},
{"rev", input.getRev()->gitRev()},
});
};
auto makeResult = [&](const Attrs & infoAttrs, StorePath && storePath)
-> std::pair<Tree, Input>
{
assert(input.getRev());
assert(!_input.getRev() || _input.getRev() == input.getRev());
input.attrs.insert_or_assign("revCount", getIntAttr(infoAttrs, "revCount"));
return {
Tree(store->toRealPath(storePath), std::move(storePath)),
input
};
};
if (input.getRev()) {
if (auto res = getCache()->lookup(store, getImmutableAttrs()))
return makeResult(res->first, std::move(res->second));
}
auto revOrRef = input.getRev() ? input.getRev()->gitRev() : *input.getRef();
Attrs mutableAttrs({
{"type", "hg"},
{"name", name},
{"url", actualUrl},
{"ref", *input.getRef()},
});
if (auto res = getCache()->lookup(store, mutableAttrs)) {
auto rev2 = Hash::parseAny(getStrAttr(res->first, "rev"), htSHA1);
if (!input.getRev() || input.getRev() == rev2) {
input.attrs.insert_or_assign("rev", rev2.gitRev());
return makeResult(res->first, std::move(res->second));
}
}
Path cacheDir = fmt("%s/nix/hg/%s", getCacheDir(), hashString(htSHA256, actualUrl).to_string(Base32, false));
/* If this is a commit hash that we already have, we don't
have to pull again. */
if (!(input.getRev()
&& pathExists(cacheDir)
&& runProgram(
RunOptions("hg", { "log", "-R", cacheDir, "-r", input.getRev()->gitRev(), "--template", "1" })
.killStderr(true)).second == "1"))
{
Activity act(*logger, lvlTalkative, actUnknown, fmt("fetching Mercurial repository '%s'", actualUrl));
if (pathExists(cacheDir)) {
try {
runProgram("hg", true, { "pull", "-R", cacheDir, "--", actualUrl });
}
catch (ExecError & e) {
string transJournal = cacheDir + "/.hg/store/journal";
/* hg throws "abandoned transaction" error only if this file exists */
if (pathExists(transJournal)) {
runProgram("hg", true, { "recover", "-R", cacheDir });
runProgram("hg", true, { "pull", "-R", cacheDir, "--", actualUrl });
} else {
throw ExecError(e.status, fmt("'hg pull' %s", statusToString(e.status)));
}
}
} else {
createDirs(dirOf(cacheDir));
runProgram("hg", true, { "clone", "--noupdate", "--", actualUrl, cacheDir });
}
}
auto tokens = tokenizeString<std::vector<std::string>>(
runProgram("hg", true, { "log", "-R", cacheDir, "-r", revOrRef, "--template", "{node} {rev} {branch}" }));
assert(tokens.size() == 3);
input.attrs.insert_or_assign("rev", Hash::parseAny(tokens[0], htSHA1).gitRev());
auto revCount = std::stoull(tokens[1]);
input.attrs.insert_or_assign("ref", tokens[2]);
if (auto res = getCache()->lookup(store, getImmutableAttrs()))
return makeResult(res->first, std::move(res->second));
Path tmpDir = createTempDir();
AutoDelete delTmpDir(tmpDir, true);
runProgram("hg", true, { "archive", "-R", cacheDir, "-r", input.getRev()->gitRev(), tmpDir });
deletePath(tmpDir + "/.hg_archival.txt");
auto storePath = store->addToStore(name, tmpDir);
Attrs infoAttrs({
{"rev", input.getRev()->gitRev()},
{"revCount", (int64_t) revCount},
});
if (!_input.getRev())
getCache()->add(
store,
mutableAttrs,
infoAttrs,
storePath,
false);
getCache()->add(
store,
getImmutableAttrs(),
infoAttrs,
storePath,
true);
return makeResult(infoAttrs, std::move(storePath));
}
};
static auto r1 = OnStartup([] { registerInputScheme(std::make_unique<MercurialInputScheme>()); });
}