sync/windows/sync_utils.hpp

0001 //////////////////////////////////////////////////////////////////////////////
0002 //
0003 // (C) Copyright Ion Gaztanaga 2005-2012. Distributed under the Boost
0004 // Software License, Version 1.0. (See accompanying file
0005 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 //
0007 // See http://www.boost.org/libs/interprocess for documentation.
0008 //
0009 //////////////////////////////////////////////////////////////////////////////
0010
0011 #ifndef BOOST_INTERPROCESS_DETAIL_SYNC_UTILS_HPP
0012 #define BOOST_INTERPROCESS_DETAIL_SYNC_UTILS_HPP
0013
0014 #ifndef BOOST_CONFIG_HPP
0015 #  include <boost/config.hpp>
0016 #endif
0017 #
0018 #if defined(BOOST_HAS_PRAGMA_ONCE)
0019 #  pragma once
0020 #endif
0021
0022 #include <boost/interprocess/detail/config_begin.hpp>
0023 #include <boost/interprocess/detail/workaround.hpp>
0024 #include <boost/interprocess/detail/win32_api.hpp>
0025 #include <boost/interprocess/sync/spin/mutex.hpp>
0026 #include <boost/interprocess/exceptions.hpp>
0027 #include <boost/interprocess/sync/scoped_lock.hpp>
0028 #include <boost/interprocess/sync/windows/winapi_semaphore_wrapper.hpp>
0029 #include <boost/interprocess/sync/windows/winapi_mutex_wrapper.hpp>
0030
0031 //Shield against external warnings
0032 #include <boost/interprocess/detail/config_external_begin.hpp>
0033 #include <boost/container/map.hpp>
0034 #include <boost/interprocess/detail/config_external_end.hpp>
0035 #include <boost/container/flat_map.hpp>
0036
0037 #include <cstddef>
0038
0039 namespace boost {
0040 namespace interprocess {
0041 namespace ipcdetail {
0042
0043 inline bool bytes_to_str(const void *mem, const std::size_t mem_length, char *out_str, std::size_t &out_length)
0044 {
0045    const std::size_t need_mem = mem_length*2+1;
0046    if(out_length < need_mem){
0047       out_length = need_mem;
0048       return false;
0049    }
0050
0051    const char Characters [] =
0052       { '0', '1', '2', '3', '4', '5', '6', '7'
0053       , '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
0054
0055    std::size_t char_counter = 0;
0056    const char *buf = (const char *)mem;
0057    for(std::size_t i = 0; i != mem_length; ++i){
0058       out_str[char_counter++] = Characters[(buf[i]&0xF0)>>4];
0059       out_str[char_counter++] = Characters[(buf[i]&0x0F)];
0060    }
0061    out_str[char_counter] = 0;
0062    return true;
0063 }
0064
0065 inline bool bytes_to_str(const void *mem, const std::size_t mem_length, wchar_t *out_str, std::size_t &out_length)
0066 {
0067    const std::size_t need_mem = mem_length*2+1;
0068    if(out_length < need_mem){
0069       out_length = need_mem;
0070       return false;
0071    }
0072
0073    const wchar_t Characters [] =
0074       { L'0', L'1', L'2', L'3', L'4', L'5', L'6', L'7'
0075       , L'8', L'9', L'A', L'B', L'C', L'D', L'E', L'F' };
0076
0077    std::size_t char_counter = 0;
0078    const char *buf = (const char *)mem;
0079    for(std::size_t i = 0; i != mem_length; ++i){
0080       out_str[char_counter++] = Characters[(buf[i]&0xF0)>>4];
0081       out_str[char_counter++] = Characters[(buf[i]&0x0F)];
0082    }
0083    out_str[char_counter] = 0;
0084    return true;
0085 }
0086
0087 class sync_id
0088 {
0089    public:
0090    typedef __int64 internal_type;
0091    sync_id()
0092    {  winapi::query_performance_counter(&rand_);  }
0093
0094    explicit sync_id(internal_type val)
0095    {  rand_ = val;  }
0096
0097    const internal_type &internal_pod() const
0098    {  return rand_;  }
0099
0100    internal_type &internal_pod()
0101    {  return rand_;  }
0102
0103    friend std::size_t hash_value(const sync_id &m)
0104    {  return static_cast<std::size_t>(m.rand_);  }
0105
0106    friend bool operator==(const sync_id &l, const sync_id &r)
0107    {  return l.rand_ == r.rand_;  }
0108
0109    friend bool operator<(const sync_id &l, const sync_id &r)
0110    {  return l.rand_ < r.rand_;  }
0111
0112    private:
0113    internal_type rand_;
0114 };
0115
0116 class sync_handles
0117 {
0118    public:
0119    enum type { MUTEX, SEMAPHORE };
0120
0121    private:
0122
0123    //key: id -> mapped: HANDLE. Hash map to allow efficient sync operations
0124    typedef boost::container::flat_map<sync_id, void*> id_map_type;
0125    //key: ordered address of the sync type -> key from id_map_type. Ordered map to allow closing handles when unmapping
0126    // Can't store iterators into id_map_type because they would get invalidated.
0127    typedef boost::container::flat_map<const void*, sync_id> addr_map_type;
0128    static const std::size_t LengthOfGlobal = sizeof("Global\\boost.ipc")-1;
0129    static const std::size_t StrSize        = LengthOfGlobal + (sizeof(sync_id)*2+1);
0130    typedef char NameBuf[StrSize];
0131
0132    void fill_name(NameBuf &name, const sync_id &id)
0133    {
0134       const char *n = "Global\\boost.ipc";
0135       std::size_t i = 0;
0136       do{
0137          name[i] = n[i];
0138          ++i;
0139       } while(n[i]);
0140       std::size_t len = sizeof(NameBuf) - LengthOfGlobal;
0141       bytes_to_str(&id.internal_pod(), sizeof(id.internal_pod()), &name[LengthOfGlobal], len);
0142    }
0143
0144    void throw_if_error(void *hnd_val)
0145    {
0146       if(!hnd_val){
0147          error_info err(static_cast<int>(winapi::get_last_error()));
0148          throw interprocess_exception(err);
0149       }
0150    }
0151
0152    void* open_or_create_semaphore(const sync_id &id, unsigned int initial_count)
0153    {
0154       NameBuf name;
0155       fill_name(name, id);
0156       permissions unrestricted_security;
0157       unrestricted_security.set_unrestricted();
0158       winapi_semaphore_wrapper sem_wrapper;
0159       bool created;
0160       sem_wrapper.open_or_create
0161          (name, (long)initial_count, winapi_semaphore_wrapper::MaxCount, unrestricted_security, created);
0162       throw_if_error(sem_wrapper.handle());
0163       return sem_wrapper.release();
0164    }
0165
0166    void* open_or_create_mutex(const sync_id &id)
0167    {
0168       NameBuf name;
0169       fill_name(name, id);
0170       permissions unrestricted_security;
0171       unrestricted_security.set_unrestricted();
0172       winapi_mutex_wrapper mtx_wrapper;
0173       mtx_wrapper.open_or_create(name, unrestricted_security);
0174       throw_if_error(mtx_wrapper.handle());
0175       return mtx_wrapper.release();
0176    }
0177
0178    public:
0179    sync_handles()
0180       : num_handles_()
0181    {}
0182
0183    ~sync_handles()
0184    {
0185       BOOST_ASSERT(num_handles_ == 0); //Sanity check that handle we don't leak handles
0186    }
0187
0188    void *obtain_mutex(const sync_id &id, const void *mapping_address, bool *popen_created = 0)
0189    {
0190       id_map_type::value_type v(id, (void*)0);
0191       scoped_lock<spin_mutex> lock(mtx_);
0192       id_map_type::iterator it = umap_.insert(v).first;
0193       void *&hnd_val = it->second;
0194       if(!hnd_val){
0195          BOOST_ASSERT(map_.find(mapping_address) == map_.end());
0196          map_[mapping_address] = id;
0197          hnd_val = open_or_create_mutex(id);
0198          if(popen_created) *popen_created = true;
0199          ++num_handles_;
0200       }
0201       else if(popen_created){
0202          BOOST_ASSERT(map_.find(mapping_address) != map_.end());
0203          *popen_created = false;
0204       }
0205
0206       return hnd_val;
0207    }
0208
0209    void *obtain_semaphore(const sync_id &id, const void *mapping_address, unsigned int initial_count, bool *popen_created = 0)
0210    {
0211       id_map_type::value_type v(id, (void*)0);
0212       scoped_lock<spin_mutex> lock(mtx_);
0213       id_map_type::iterator it = umap_.insert(v).first;
0214       void *&hnd_val = it->second;
0215       if(!hnd_val){
0216          BOOST_ASSERT(map_.find(mapping_address) == map_.end());
0217          map_[mapping_address] = id;
0218          hnd_val = open_or_create_semaphore(id, initial_count);
0219          if(popen_created) *popen_created = true;
0220          ++num_handles_;
0221       }
0222       else if(popen_created){
0223          BOOST_ASSERT(map_.find(mapping_address) != map_.end());
0224          *popen_created = false;
0225       }
0226       return hnd_val;
0227    }
0228
0229    void destroy_handle(const sync_id &id, const void *mapping_address)
0230    {
0231       scoped_lock<spin_mutex> lock(mtx_);
0232       id_map_type::iterator it = umap_.find(id);
0233       id_map_type::iterator itend = umap_.end();
0234
0235       if(it != itend){
0236          winapi::close_handle(it->second);
0237          --num_handles_;
0238          std::size_t i = map_.erase(mapping_address);
0239          (void)i;
0240          BOOST_ASSERT(i == 1);   //The entry should be there
0241          umap_.erase(it);
0242       }
0243    }
0244
0245    void destroy_syncs_in_range(const void *addr, std::size_t size)
0246    {
0247       const void *low_id(addr);
0248       const void *hig_id(static_cast<const char*>(addr)+size);
0249       scoped_lock<spin_mutex> lock(mtx_);
0250       addr_map_type::iterator itlow(map_.lower_bound(low_id)),
0251                          ithig(map_.lower_bound(hig_id)),
0252                          it(itlow);
0253       for (; it != ithig; ++it){
0254          sync_id ukey = it->second;
0255          id_map_type::iterator uit = umap_.find(ukey);
0256          BOOST_ASSERT(uit != umap_.end());
0257          void * const hnd = uit->second;
0258          umap_.erase(ukey);
0259          int ret = winapi::close_handle(hnd);
0260          --num_handles_;
0261          BOOST_ASSERT(ret != 0); (void)ret;  //Sanity check that handle was ok
0262       }
0263
0264       map_.erase(itlow, ithig);
0265    }
0266
0267    private:
0268    spin_mutex mtx_;
0269    id_map_type umap_;
0270    addr_map_type map_;
0271    std::size_t num_handles_;
0272 };
0273
0274
0275 }  //namespace ipcdetail {
0276 }  //namespace interprocess {
0277 }  //namespace boost {
0278
0279 #include <boost/interprocess/detail/config_end.hpp>
0280
0281 #endif   //BOOST_INTERPROCESS_DETAIL_SYNC_UTILS_HPP