lix/src/libstore/fetchers/mercurial.cc
2020-01-29 23:14:23 +01:00

281 lines
9.4 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#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 {
struct MercurialInput : Input
{
ParsedURL url;
std::optional<std::string> ref;
std::optional<Hash> rev;
MercurialInput(const ParsedURL & url) : url(url)
{
type = "hg";
}
bool operator ==(const Input & other) const override
{
auto other2 = dynamic_cast<const MercurialInput *>(&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 (rev) url2.query.insert_or_assign("rev", rev->gitRev());
if (ref) url2.query.insert_or_assign("ref", *ref);
return url2.to_string();
}
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<MercurialInput>(*this);
if (ref) res->ref = ref;
if (rev) res->rev = rev;
return res;
}
std::optional<Path> getSourcePath() const
{
if (url.scheme == "hg+file" && !ref && !rev)
return url.path;
return {};
}
std::pair<bool, std::string> getActualUrl() const
{
bool isLocal = url.scheme == "hg+file";
return {isLocal, isLocal ? url.path : std::string(url.base, 3)};
}
std::pair<Tree, std::shared_ptr<const Input>> fetchTreeInternal(nix::ref<Store> store) const override
{
auto name = "source";
auto input = std::make_shared<MercurialInput>(*this);
auto [isLocal, actualUrl_] = getActualUrl();
auto actualUrl = actualUrl_; // work around clang bug
// FIXME: return lastModified.
// FIXME: don't clone local repositories.
if (!input->ref && !input->rev && 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->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, true, htSHA256, filter);
return {Tree {
.actualPath = store->printStorePath(storePath),
.storePath = std::move(storePath),
}, input};
}
}
if (!input->ref) input->ref = "default";
Path cacheDir = fmt("%s/nix/hg/%s", getCacheDir(), hashString(htSHA256, actualUrl).to_string(Base32, false));
assert(input->rev || input->ref);
auto revOrRef = input->rev ? input->rev->gitRev() : *input->ref;
Path stampFile = fmt("%s/.hg/%s.stamp", cacheDir, hashString(htSHA512, revOrRef).to_string(Base32, false));
/* If we haven't pulled this repo less than tarball-ttl seconds,
do so now. */
time_t now = time(0);
struct stat st;
if (stat(stampFile.c_str(), &st) != 0 ||
(uint64_t) st.st_mtime + settings.tarballTtl <= (uint64_t) now)
{
/* Except that if this is a commit hash that we already have,
we don't have to pull again. */
if (!(input->rev
&& pathExists(cacheDir)
&& runProgram(
RunOptions("hg", { "log", "-R", cacheDir, "-r", input->rev->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 });
}
}
writeFile(stampFile, "");
}
auto tokens = tokenizeString<std::vector<std::string>>(
runProgram("hg", true, { "log", "-R", cacheDir, "-r", revOrRef, "--template", "{node} {rev} {branch}" }));
assert(tokens.size() == 3);
input->rev = Hash(tokens[0], htSHA1);
auto revCount = std::stoull(tokens[1]);
input->ref = tokens[2];
std::string storeLinkName = hashString(htSHA512, name + std::string("\0"s) + input->rev->gitRev()).to_string(Base32, false);
Path storeLink = fmt("%s/.hg/%s.link", cacheDir, storeLinkName);
try {
auto json = nlohmann::json::parse(readFile(storeLink));
assert(json["name"] == name && json["rev"] == input->rev->gitRev());
auto storePath = store->parseStorePath((std::string) json["storePath"]);
if (store->isValidPath(storePath)) {
printTalkative("using cached Mercurial store path '%s'", store->printStorePath(storePath));
return {Tree {
.actualPath = store->printStorePath(storePath),
.storePath = std::move(storePath),
.rev = input->rev,
.revCount = revCount,
}, input};
}
} catch (SysError & e) {
if (e.errNo != ENOENT) throw;
}
Path tmpDir = createTempDir();
AutoDelete delTmpDir(tmpDir, true);
runProgram("hg", true, { "archive", "-R", cacheDir, "-r", input->rev->gitRev(), tmpDir });
deletePath(tmpDir + "/.hg_archival.txt");
auto storePath = store->addToStore(name, tmpDir);
nlohmann::json json;
json["storePath"] = store->printStorePath(storePath);
json["uri"] = actualUrl;
json["name"] = name;
json["branch"] = *input->ref;
json["rev"] = input->rev->gitRev();
json["revCount"] = revCount;
writeFile(storeLink, json.dump());
return {Tree {
.actualPath = store->printStorePath(storePath),
.storePath = std::move(storePath),
.rev = input->rev,
.revCount = revCount,
}, input};
}
};
struct MercurialInputScheme : InputScheme
{
std::unique_ptr<Input> inputFromURL(const ParsedURL & url) override
{
if (url.scheme != "hg+http" &&
url.scheme != "hg+https" &&
url.scheme != "hg+ssh" &&
url.scheme != "hg+file") return nullptr;
auto input = std::make_unique<MercurialInput>(url);
input->url.query.clear();
for (auto &[name, value] : url.query) {
if (name == "rev") {
if (!std::regex_match(value, revRegex))
throw BadURL("Mercurial URL '%s' contains an invalid commit hash", url.url);
input->rev = Hash(value, htSHA1);
}
else if (name == "ref") {
if (!std::regex_match(value, refRegex))
throw BadURL("Mercurial URL '%s' contains an invalid branch/tag name", url.url);
input->ref = value;
}
else input->url.query.insert_or_assign(name, value);
}
return input;
}
};
static auto r1 = OnStartup([] { registerInputScheme(std::make_unique<MercurialInputScheme>()); });
}