Initial import of draft version of the object store based on both Ceph and VFS.

Some legacy utilities from castor were imported alongside, with some adaptations.

.gitignore

+nbproject/

CMakeLists.txt

@@ -7,6 +7,11 @@ project(cta)
 set(CMAKE_C_FLAGS_RELWITHDEBINFO "-g")
 set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-g")
 
+set(CMAKE_DISABLE_SOURCE_CHANGES ON)
+set(CMAKE_DISABLE_IN_SOURCE_BUILD ON)
+list(APPEND CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake)
+
 add_subdirectory(libs)
 add_subdirectory(xroot_clients)
 add_subdirectory(xroot_plugins)
+add_subdirectory(objectstore)

cmake/FindProtobuf.cmake

+# From, https://raw.githubusercontent.com/Kitware/CMake/master/Modules/FindProtobuf.cmake
+# cut down to solve our problem and nothing more
+#=============================================================================
+# Copyright 2009 Kitware, Inc.
+# Copyright 2009-2011 Philip Lowman <philip@yhbt.com>
+# Copyright 2008 Esben Mose Hansen, Ange Optimization ApS
+#
+# Distributed under the OSI-approved BSD License (the "License");
+# see accompanying file Copyright.txt for details.
+#
+# This software is distributed WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the License for more information.
+#=============================================================================
+# (To distribute this file outside of CMake, substitute the full
+#  License text for the above reference.)
+
+find_program(PROTOBUF_PROTOC_EXECUTABLE
+    NAMES protoc
+    DOC "The Google Protocol Buffers Compiler"
+)
+
+message(STATUS "protoc is at ${PROTOBUF_PROTOC_EXECUTABLE} ")
+function(PROTOBUF_GENERATE_CPP SRCS HDRS)
+  if(NOT ARGN)
+    message(SEND_ERROR "Error: PROTOBUF_GENERATE_CPP() called without any proto files")
+    return()
+  endif()
+
+  set(_protobuf_include_path -I ${CMAKE_CURRENT_SOURCE_DIR})
+
+  set(${SRCS})
+  set(${HDRS})
+  foreach(FIL ${ARGN})
+    get_filename_component(ABS_FIL ${FIL} ABSOLUTE)
+    get_filename_component(FIL_WE ${FIL} NAME_WE)
+
+    list(APPEND ${SRCS} "${CMAKE_CURRENT_BINARY_DIR}/${FIL_WE}.pb.cc")
+    list(APPEND ${HDRS} "${CMAKE_CURRENT_BINARY_DIR}/${FIL_WE}.pb.h")
+
+    add_custom_command(
+      OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/${FIL_WE}.pb.cc"
+             "${CMAKE_CURRENT_BINARY_DIR}/${FIL_WE}.pb.h"
+      COMMAND  ${PROTOBUF_PROTOC_EXECUTABLE}
+      ARGS --cpp_out  ${CMAKE_CURRENT_BINARY_DIR} ${_protobuf_include_path} ${ABS_FIL}
+      DEPENDS ${ABS_FIL}
+      COMMENT "Running C++ protocol buffer compiler on ${FIL}"
+      VERBATIM ) 
+  endforeach()
+
+  set_source_files_properties(${${SRCS}} ${${HDRS}} PROPERTIES GENERATED TRUE)
+  set(${SRCS} ${${SRCS}} PARENT_SCOPE)
+  set(${HDRS} ${${HDRS}} PARENT_SCOPE)
+endfunction()
\ No newline at end of file

objectstore/Agent.hpp

+#pragma once
+
+#include "ObjectStores.hpp"
+#include "ContextHandle.hpp"
+
+class Agent {
+public:
+  Agent(ObjectStore & os): m_objectStore(os) {};
+  ~Agent() {
+    for (size_t i=0; i < c_handleCount; i++) {
+      m_contexts[i].release();
+    }
+  }
+  void act() {
+    
+  }
+private:
+  ObjectStore & m_objectStore;
+  static const size_t c_handleCount = 100;
+  ContextHandleImplementation<myOS> m_contexts[c_handleCount];
+  ContextHandleImplementation<myOS> getFreeContext() {
+    for (size_t i=0; i < c_handleCount; i++) {
+      if (!m_contexts[i].isSet())
+        return m_contexts[i];
+    }
+    throw cta::exception::Exception("Could not find free context slot");
+  }
+};
\ No newline at end of file

objectstore/AgentId.hpp

+#pragma once
+
+#include <sstream>
+#include <string>
+#include <sys/syscall.h>
+#include <ctime>
+
+class AgentId {
+public:
+  AgentId(std::string agentType): m_nextId(0) {
+    std::stringstream aid;
+    // Get time
+    time_t now = time(0);
+    struct tm localNow;
+    localtime_r(&now, &localNow);
+    // Get hostname
+    char host[200];
+    cta::exception::Errnum::throwOnMinusOne(gethostname(host, sizeof(host)),
+      "In AgentId::AgentId:  failed to gethostname");
+    // gettid is a safe system call (never fails)
+    aid << agentType << "-" << host << "-" << syscall(SYS_gettid) << "-"
+      << 1900 + localNow.tm_year
+      << std::setfill('0') << std::setw(2) << 1 + localNow.tm_mon
+      << localNow.tm_mday << "-"
+      << localNow.tm_hour << ":"
+      << localNow.tm_min << ":"
+      << localNow.tm_sec;
+    m_agentId = aid.str();
+  }
+  std::string name() {
+    return m_agentId;
+  }
+  std::string nextId() {
+    std::stringstream id;
+    id << m_agentId << "-" << m_nextId++;
+    return id.str();
+  }
+private:
+  std::string m_agentId;
+  uint64_t m_nextId;
+};
\ No newline at end of file

objectstore/CMakeLists.txt

+cmake_minimum_required (VERSION 2.6)
+
+include_directories(${CMAKE_CURRENT_SOURCE_DIR})
+include_directories(${CMAKE_BINARY_DIR})
+
+find_package(Protobuf)
+
+set (CTAProtoFiles
+  cta.proto)
+
+PROTOBUF_GENERATE_CPP(CTAProtoSources CTAProtoHeaders ${CTAProtoFiles})
+
+add_executable (tapeResourceMangerTest tapeResourceManagerTest.cpp
+  ${CTAProtoSources}
+  exception/Backtrace.cpp
+  exception/Errnum.cpp
+  exception/Exception.cpp
+  exception/strerror_r_wrapper.cpp
+  threading/ChildProcess.cpp
+  threading/Mutex.cpp
+  threading/Threading.cpp)
+
+target_link_libraries(tapeResourceMangerTest
+  protobuf
+  rados)

objectstore/ContextHandle.hpp

+#pragma once
+
+#include "ObjectStores.hpp"
+
+template <class C>
+class ContextHandleImplementation: public ContextHandle {};
+
+template <>
+class ContextHandleImplementation <ObjectStoreVFS>: public ContextHandle {
+public:
+  ContextHandleImplementation(): m_set(false), m_fd(-1) {}
+  void set(int fd) { m_set = true;  m_fd = fd; __sync_synchronize(); }
+  int get(int) { return m_fd; }
+  void reset() { m_set = false; m_fd = -1; __sync_synchronize(); }
+  bool isSet() { return m_set; }
+  void release() { __sync_synchronize(); if (m_set && -1 != m_fd) ::close(m_fd); reset(); } 
+private:
+  bool m_set;
+  volatile int m_fd;
+};
+
+template <>
+class ContextHandleImplementation <ObjectStoreRados>: public ContextHandle {
+public:
+  ContextHandleImplementation(): m_set(false) {}
+  void set(int) { m_set = true; }
+  void reset() { m_set = false; }
+  bool isSet() { return m_set; }
+  void release() { reset(); }
+private:
+  bool m_set;
+};
\ No newline at end of file

objectstore/FIFO.hpp

+#pragma once
+
+#include "ObjectOps.hpp"
+#include "exception/Exception.hpp"
+
+class FIFO: private ObjectOps<cta::objectstore::FIFO> {
+public:
+  FIFO(ObjectStore & os, const std::string & name, ContextHandle & context):
+  ObjectOps<cta::objectstore::FIFO>(os, name),
+  m_locked(false) {
+    cta::objectstore::FIFO fs;
+    updateFromObjectStore(fs, context);
+  }
+  
+  void lock(ContextHandle & context) {
+    if (m_locked) throw cta::exception::Exception(
+      "In FIFO::lock: already locked");
+    lockExclusiveAndRead(m_currentState, context);
+    m_locked = true;
+  }
+  
+  std::string peek() {
+    std::string ret;
+    if (!m_locked) throw cta::exception::Exception(
+      "In FIFO::pop: FIFO should be locked");
+    return m_currentState.name(m_currentState.readpointer());
+    return ret;
+  }
+  
+  void popAndUnlock(ContextHandle & context) {
+    if (!m_locked) throw cta::exception::Exception(
+      "In FIFO::pop: FIFO should be locked");
+    m_currentState.set_readpointer(m_currentState.readpointer()+1);
+    if (m_currentState.readpointer() > 100) {
+      compactCurrentState();
+    }
+    write(m_currentState);
+    unlock(context);
+    m_locked = false;
+  }
+  
+  void push(std::string name, ContextHandle & context) {
+    cta::objectstore::FIFO fs;
+    lockExclusiveAndRead(fs, context);
+    fs.add_name(name);
+    write(fs);
+    unlock(context);
+  }
+  
+  std::string dump(ContextHandle & context) {
+    cta::objectstore::FIFO fs;
+    updateFromObjectStore(fs, context);
+    std::stringstream ret;
+    ret<< "<<<< FIFO dump start" << std::endl
+      << "Read pointer=" << fs.readpointer() << std::endl
+      << "Array size=" << fs.name_size() << std::endl;
+    for (int i=fs.readpointer(); i<fs.name_size(); i++) {
+      ret << "name[phys=" << i << " ,log=" << i-fs.readpointer()
+          << "]=" << fs.name(i) << std::endl;
+    }
+    ret<< ">>>> FIFO dump end." << std::endl;
+    return ret.str();
+  }
+  
+private:
+  bool m_locked;
+  cta::objectstore::FIFO m_currentState;
+  
+  void compactCurrentState() {
+    uint64_t oldReadPointer = m_currentState.readpointer();
+    uint64_t oldSize = m_currentState.name_size();
+    // Copy the elements at position oldReadPointer + i to i (squash all)
+    // before the read pointer
+    for (int i = oldReadPointer; i<m_currentState.name_size(); i++) {
+      *m_currentState.mutable_name(i-oldReadPointer) = m_currentState.name(i);
+    }
+    // Shorten the name array by oldReadPointer elements
+    for (uint64_t i = 0; i < oldReadPointer; i++) {
+      m_currentState.mutable_name()->RemoveLast();
+    }
+    // reset the read pointer
+    m_currentState.set_readpointer(0);
+    // Check the size is as expected
+    if ((uint64_t)m_currentState.name_size() != oldSize - oldReadPointer) {
+      std::stringstream err;
+      err << "In FIFO::compactCurrentState: wrong size after compaction: "
+        << "oldSize=" << oldSize << " oldReadPointer=" << oldReadPointer
+        << " newSize=" << m_currentState.name_size();
+      throw cta::exception::Exception(err.str());
+    }
+  }
+};
\ No newline at end of file

objectstore/JobPool.hpp

+#pragma once
+
+#include "ObjectOps.hpp"
+#include "FIFO.hpp"
+
+class JobPool: private ObjectOps<cta::objectstore::jobPool> {
+public:
+  JobPool(ObjectStore & os, const std::string & name, ContextHandle & context):
+  ObjectOps<cta::objectstore::jobPool>(os, name) {
+    cta::objectstore::jobPool jps;
+    updateFromObjectStore(jps, context);
+  }
+  
+  void PostRecallJob (const std::string & string, ContextHandle & context) {
+    cta::objectstore::jobPool jps;
+    lockExclusiveAndRead(jps, context);
+  }
+  
+private:
+  // The following functions are hidden from the user in order to provide
+  // higher level functionnality
+  //std::string get
+  
+};
\ No newline at end of file

objectstore/ObjectOps.hpp

+#pragma once
+
+#include "ObjectStores.hpp"
+
+template <class C>
+class ObjectOps {
+public:
+  ObjectOps(ObjectStore & os, const std::string & name):m_name(name),
+    m_objectStore(os) {}
+  
+  void updateFromObjectStore (C & val, ContextHandle & context) {
+    m_objectStore.lockShared(m_name, context);
+    std::string reStr = m_objectStore.read(m_name);
+    m_objectStore.unlock(m_name, context);
+    val.ParseFromString(reStr);
+  }
+  
+  void lockExclusiveAndRead (C & val, ContextHandle & context) {
+    m_objectStore.lockExclusive(m_name, context);
+    // Re-read to get latest version (lock upgrade could be useful here)
+    std::string reStr = m_objectStore.read(m_name);
+    cta::objectstore::RootEntry res;
+    val.ParseFromString(reStr);
+  }
+  
+  void write (C & val) {
+    m_objectStore.atomicOverwrite(m_name, val.SerializeAsString());
+  }
+  
+  void unlock (ContextHandle & context) {
+    // release the lock, and return the register name
+    m_objectStore.unlock(m_name, context);
+  }
+  
+  template <class C2>
+  void writeChild (const std::string & name, C2 & val) {
+    m_objectStore.atomicOverwrite(name, val.SerializeAsString());
+  }
+private:
+  std::string m_name;
+  ObjectStore & m_objectStore;
+};
\ No newline at end of file

objectstore/ObjectStores.hpp

+#pragma once
+
+#include <string>
+#include <errno.h>
+#include <stdlib.h>
+#include <ftw.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <sys/file.h>
+#include <sys/syscall.h>
+#include <fstream>
+#include <rados/librados.hpp>
+
+class ContextHandle {
+public:
+  template <typename T>
+  void set(T);
+  template <typename T>
+  T get(T);
+  void reset();
+  bool isSet();
+  void release();
+};
+
+class ObjectStore {
+public:
+  virtual ~ObjectStore() {}
+  virtual void atomicOverwrite(std::string name, std::string content) = 0;
+  virtual std::string read(std::string name) = 0;
+  virtual void lockShared(std::string name, ContextHandle & context) = 0;
+  virtual void lockExclusive(std::string name, ContextHandle & context) = 0;
+  virtual void unlock(std::string name, ContextHandle & context) = 0;
+  virtual std::string path() { return ""; }
+  virtual std::string user() { return ""; }
+  virtual std::string pool() { return ""; }
+};
+
+
+
+// An implementation of the object store primitives, using flock to lock,
+// so that several threads can compete for the same file (locks are per file
+// descriptor). The lock will be done on a special file (XXXX.lock), which will
+// not be moved (as opposed to the content itself, which needs to be moved to
+// be atomically created)
+// The context here is a pointer to an element of a per thread int array, that will
+// hold the file descriptors. This int is chosen for containing -1 (free).
+// When the thread is killed, the destructor will be able to safely close
+// all the file descriptors in the array.
+// The fd will be deleted from the array before calling close.
+// This will be a fd leak source, but this might be good enough for this test's 
+// purpose.
+class ObjectStoreVFS: public ObjectStore {
+public:
+  ObjectStoreVFS():m_deleteOnExit(true) {
+    // Create the directory for storage
+    char tplt[] = "/tmp/jobStoreVFSXXXXXX";
+    mkdtemp(tplt);
+    // If template is an empty string, we failed, otherwise, we're fine.
+    if (*tplt) {
+      m_root = tplt;
+    } else {
+      throw cta::exception::Errnum("Failed to create temporary directory"); 
+    }
+  }
+  ObjectStoreVFS(std::string path, std::string user, std::string pool): 
+    m_root(path), m_deleteOnExit(false) {}
+  virtual ~ObjectStoreVFS() {
+    if (m_deleteOnExit) {
+      // Delete the created directories recursively
+      nftw (m_root.c_str(), deleteFileOrDirectory, 100, FTW_DEPTH);
+    }
+  }
+  virtual std::string path() {
+    return m_root;
+  }
+  virtual void atomicOverwrite(std::string name, std::string content) {
+    // When entering here, we should hold an exclusive lock on the *context
+    // file descriptor. We will create a new file, lock it immediately exclusively,
+    // create the new content in it, move it over the old file, and close the *context
+    // file descriptor.
+    std::string tempPath = m_root+"/." + name + ".pre-overwrite";
+    std::string targetPath = m_root+"/" + name;
+    // Create the new version of the file, make sure it's visible, lock it.
+    int fd= ::creat(tempPath.c_str(), S_IRWXU);
+    cta::exception::Errnum::throwOnMinusOne(fd,
+      "In ObjectStoreVFS::atomicOverwrite, failed to creat the pre-overwrite file");
+    cta::exception::Errnum::throwOnMinusOne(
+      ::write(fd, content.c_str(), content.size()),
+      "In ObjectStoreVFS::atomicOverwrite, failed to write to the pre-overwrite file");
+    cta::exception::Errnum::throwOnMinusOne(::close(fd),
+      "In ObjectStoreVFS::atomicOverwrite, failed to close the pre-overwrite file");
+    cta::exception::Errnum::throwOnMinusOne(
+      ::rename(tempPath.c_str(), targetPath.c_str()),
+      "In ObjectStoreVFS::atomicOverwrite, failed to rename the file");
+  }
+  virtual std::string read(std::string name) {
+    std::string path = m_root+"/" + name;
+    std::string ret;
+    std::ifstream file(path.c_str());
+    if (!file) {
+      throw cta::exception::Errnum(
+        std::string("In ObjectStoreVFS::read, failed to open file for read: ") +
+        path);
+    }
+    char buff[200];
+    while(!file.eof()) {
+      file.read(buff, sizeof(buff));
+      ret.append(buff,file.gcount());
+    }
+    return ret;
+  }
+  
+  void lockHelper(std::string name, ContextHandle & context, int type) {
+    std::string path = m_root + "/" + name + ".lock";
+    context.set(::open(path.c_str(), O_CREAT, S_IRWXU));
+    cta::exception::Errnum::throwOnMinusOne(context.get(0),
+      "In ObjectStoreVFS::lockHelper, failed to open the lock file.");
+    cta::exception::Errnum::throwOnMinusOne(::flock(context.get(0), LOCK_EX),
+      "In ObjectStoreVFS::lockHelper, failed to flock the lock file.");
+  }
+  
+  virtual void lockExclusive(std::string name, ContextHandle & context) {
+    lockHelper(name, context, LOCK_EX);
+  }
+
+  virtual void lockShared(std::string name, ContextHandle & context) {
+    lockHelper(name, context, LOCK_SH);
+  }
+
+  virtual void unlock(std::string name, ContextHandle & context) {
+    ::flock(context.get(0), LOCK_UN);
+    int fd= context.get(0);
+    context.reset();
+    ::close(fd);
+  }
+  
+
+
+
+private:
+  std::string m_root;
+  bool m_deleteOnExit;
+  // Utility function to be used in the destructor
+  static int deleteFileOrDirectory(const char *fpath, const struct stat *sb,
+                        int tflag, struct FTW *ftwbuf) {
+    switch (tflag) {
+      case FTW_D:
+      case FTW_DNR:
+      case FTW_DP:
+        rmdir (fpath);
+        break;
+      default:
+        unlink (fpath);
+        break;
+    }
+    return 0;
+  }
+};
+
+class ObjectStoreRados: public ObjectStore {
+public:
+  ObjectStoreRados(std::string path, std::string userId, std::string pool): 
+    m_user(userId), m_pool(pool), m_cluster(), m_radosCtx() {
+    cta::exception::Errnum::throwOnNonZero(m_cluster.init(userId.c_str()),
+      "In ObjectStoreRados::ObjectStoreRados, failed to m_cluster.init");
+    try {
+      cta::exception::Errnum::throwOnNonZero(m_cluster.conf_read_file(NULL),
+        "In ObjectStoreRados::ObjectStoreRados, failed to m_cluster.conf_read_file");
+      cta::exception::Errnum::throwOnNonZero(m_cluster.conf_parse_env(NULL),
+        "In ObjectStoreRados::ObjectStoreRados, failed to m_cluster.conf_read_file");
+      cta::exception::Errnum::throwOnNonZero(m_cluster.connect(),
+        "In ObjectStoreRados::ObjectStoreRados, failed to m_cluster.connect");
+      cta::exception::Errnum::throwOnNonZero(m_cluster.ioctx_create(pool.c_str(), m_radosCtx),
+        "In ObjectStoreRados::ObjectStoreRados, failed to m_cluster.ioctx_create");
+    } catch (...) {
+      m_cluster.shutdown();
+      throw;
+    }
+  }
+  virtual ~ObjectStoreRados() {
+    m_radosCtx.close();
+    m_cluster.shutdown();
+  }
+  virtual std::string user() {
+    return m_user;
+  }
+  virtual std::string pool() {
+    return m_pool;
+  }
+  virtual void atomicOverwrite(std::string name, std::string content) {
+    ceph::bufferlist bl;
+    bl.append(content.c_str(), content.size());
+    cta::exception::Errnum::throwOnNonZero(m_radosCtx.write_full(name, bl),
+      std::string("In ObjectStoreRados::atomicOverwrite, failed to write_full ")
+      + name);
+  }
+
+  virtual std::string read(std::string name) {
+    std::string ret;
+    uint64_t size;
+    time_t time;
+    cta::exception::Errnum::throwOnNonZero(m_radosCtx.stat(name, &size, &time),
+      std::string("In ObjectStoreRados::read,  failed to stat ")
+      + name);
+    librados::bufferlist bl;
+    cta::exception::Errnum::throwOnNegative(m_radosCtx.read(name, bl, size, 0),
+      std::string("In ObjectStoreRados::read,  failed to read ")
+      + name);
+    bl.copy(0, size, ret);
+    return ret;
+  }
+
+
+  virtual void lockExclusive(std::string name, ContextHandle & context) {
+    // Build a unique client name: host:thread
+    char buff[200];
+    cta::exception::Errnum::throwOnMinusOne(gethostname(buff, sizeof(buff)),
+      "In ObjectStoreRados::lockExclusive:  failed to gethostname");
+    pid_t tid = syscall(SYS_gettid);
+    std::stringstream client;
+    client << buff << ":" << tid;
+    struct timeval tv;
+    tv.tv_usec = 0;
+    tv.tv_sec = 60;
+    int rc;
+    do {
+      rc=m_radosCtx.lock_exclusive(name, "lock", client.str(), "", &tv, 0);
+    } while (-EBUSY==rc);
+    if (0!=rc) {
+      std::cout << "Oh-oh, rc=" << rc << std::endl;
+    }
+    cta::exception::Errnum::throwOnNonZero(rc,
+      std::string("In ObjectStoreRados::lockExclusive,  failed to lock_exclusive ")+
+      name);
+  }
+
+
+  virtual void lockShared(std::string name, ContextHandle & context) {
+    // Build a unique client name: host:thread
+    char buff[200];
+    cta::exception::Errnum::throwOnMinusOne(gethostname(buff, sizeof(buff)),