Commit 09213be9 authored by Ramon Nou's avatar Ramon Nou
Browse files

Record repair journal owner identity

parent 6532a9a0

include/client/rpc/repair_journal_lock.hpp

+43 −0
Changes for include/client/rpc/repair_journal_lock.hpp: 43 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -17,12 +17,21 @@ 
#include <unistd.h>



#include <cerrno>

#include <chrono>

#include <cstdint>

#include <cstring>

#include <stdexcept>

#include <string>

#include <sys/types.h>



namespace gkfs::rpc {



struct repair_journal_owner {

    std::string hostname;

    pid_t pid{};

    uint64_t acquired_at{};

};



/**

 * @brief Owns the advisory process lock for a client-local repair journal.

 *
@@ -68,7 +77,34 @@ public: 
                                     journal_path + "': " + ::strerror(error));

        }



        repair_journal_owner owner;

        owner.hostname.resize(255);

        if(::gethostname(owner.hostname.data(), owner.hostname.size()) != 0) {

            owner.hostname = "unknown";

        } else {

            owner.hostname.resize(std::strlen(owner.hostname.c_str()));

        }

        owner.pid = ::getpid();

        owner.acquired_at = static_cast<uint64_t>(

                std::chrono::duration_cast<std::chrono::seconds>(

                        std::chrono::system_clock::now().time_since_epoch())

                        .count());



        const auto record = "hostname=" + owner.hostname + "\n" +

                            "pid=" + std::to_string(owner.pid) + "\n" +

                            "acquired_at=" + std::to_string(owner.acquired_at) +

                            "\n";

        if(::ftruncate(candidate.get(), 0) != 0 ||

           ::write(candidate.get(), record.data(), record.size()) !=

                   static_cast<ssize_t>(record.size())) {

            const auto error = errno;

            throw std::runtime_error(

                    "Unable to write replica repair journal owner record '" +

                    journal_path + "': " + ::strerror(error));

        }



        fd_ = std::move(candidate);

        owner_ = std::move(owner);

    }



    void
@@ -78,6 +114,7 @@ public: 
            fd_.reset();

        }

        lock_path_.clear();

        owner_ = {};

    }



    [[nodiscard]] bool
@@ -90,9 +127,15 @@ public: 
        return lock_path_;

    }



    [[nodiscard]] const repair_journal_owner&

    owner() const noexcept {

        return owner_;

    }



private:

    gkfs::utils::unique_fd fd_;

    std::string lock_path_;

    repair_journal_owner owner_;

};



} // namespace gkfs::rpc

tests/unit/test_repair_journal_lock.cpp

+12 −0
Changes for tests/unit/test_repair_journal_lock.cpp: 12 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -12,6 +12,8 @@ 
#include <catch2/catch_all.hpp>



#include <filesystem>

#include <fstream>

#include <sstream>

#include <unistd.h>



namespace {
@@ -35,6 +37,15 @@ TEST_CASE("repair journal lock has exclusive process ownership", 
        first.acquire(journal.string());

        REQUIRE(first.owns_lock());

        REQUIRE(first.path() == lock_path);

        REQUIRE(first.owner().pid == ::getpid());

        REQUIRE_FALSE(first.owner().hostname.empty());

        REQUIRE(first.owner().acquired_at > 0);



        std::ifstream owner_record(lock_path);

        std::stringstream contents;

        contents << owner_record.rdbuf();

        REQUIRE(contents.str().find("pid=" + std::to_string(::getpid())) !=

                std::string::npos);



        gkfs::rpc::repair_journal_lock second;

        REQUIRE_THROWS_WITH(second.acquire(journal.string()),
@@ -55,4 +66,5 @@ TEST_CASE("empty repair journal path does not create a lock", 
    gkfs::rpc::repair_journal_lock lock;

    REQUIRE_NOTHROW(lock.acquire(""));

    REQUIRE_FALSE(lock.owns_lock());

    REQUIRE(lock.owner().hostname.empty());

}