Fixes #152 ("Handle EINTR in shared_memory_object")

Author: igaztanaga

doc/interprocess.qbk

@@ -6778,11 +6778,13 @@ thank them:
   You can obtain the pre-Boost 1.87 ABI #defining `BOOST_INTERPROCESS_SEGMENT_MANAGER_ABI` to `1` before including Boost.Interprocess headers.
 
 *  Fixed bugs:
+   * [@https://github.com/boostorg/interprocess/issues/152   GitHub #152 (['"Handle EINTR in shared_memory_object"])].
+   * [@https://github.com/boostorg/interprocess/issues/173   GitHub #173 (['"Managed shared memory segment value not aligned"])].
    * [@https://github.com/boostorg/interprocess/issues/192   GitHub #192 (['"managed_windows_shared_memory crash on destruction"])].
    * [@https://github.com/boostorg/interprocess/issues/199   GitHub #199 (['"missing/misused m_is_wide in char_wchar_holder assignment operators"])].
    * [@https://github.com/boostorg/interprocess/issues/210   GitHub #210 (['"Bug in boost::interprocess::ipcdetail::sync_handles::obtain_mutex"])].
    * [@https://github.com/boostorg/interprocess/issues/215   GitHub #215 (['"Alignment problem with boost/interprocess/segment_manager on SPARC 32Bit"])].
-
+   * [@https://github.com/boostorg/interprocess/issues/217   GitHub #217 (['"managed_map_file find_or_construct does not return Cache aligned memory"])].
 
 [endsect]
 

include/boost/interprocess/shared_memory_object.hpp

@@ -186,6 +186,11 @@ class shared_memory_object
    file_handle_t     m_handle;
    mode_t            m_mode;
    char_wchar_holder m_filename;
+
+   #ifdef BOOST_INTERPROCESS_POSIX_SHARED_MEMORY_OBJECTS
+   static int eintr_aware_shm_open(const char* name, int oflag, ::mode_t mode);
+   #endif
+
    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
 };
 
@@ -374,13 +379,13 @@ inline bool shared_memory_object::priv_open_or_create
       case ipcdetail::DoOpen:
       {
          //No oflag addition
-         m_handle = shm_open(fname.c_str(), oflag, unix_perm);
+         m_handle = eintr_aware_shm_open(fname.c_str(), oflag, unix_perm);
       }
       break;
       case ipcdetail::DoCreate:
       {
          oflag |= (O_CREAT | O_EXCL);
-         m_handle = shm_open(fname.c_str(), oflag, unix_perm);
+         m_handle = eintr_aware_shm_open(fname.c_str(), oflag, unix_perm);
          if(m_handle >= 0){
             ::fchmod(m_handle, unix_perm);
          }
@@ -392,14 +397,14 @@ inline bool shared_memory_object::priv_open_or_create
          //with "O_CREAT" only we don't know if we've created or opened the shm.
          while(true){
             //Try to create shared memory
-            m_handle = shm_open(fname.c_str(), oflag | (O_CREAT | O_EXCL), unix_perm);
+            m_handle = eintr_aware_shm_open(fname.c_str(), oflag | (O_CREAT | O_EXCL), unix_perm);
             //If successful change real permissions
             if(m_handle >= 0){
                ::fchmod(m_handle, unix_perm);
             }
             //If already exists, try to open
             else if(errno == EEXIST){
-               m_handle = shm_open(fname.c_str(), oflag, unix_perm);
+               m_handle = eintr_aware_shm_open(fname.c_str(), oflag, unix_perm);
                //If open fails and errno tells the file does not exist
                //(shm was removed between creation and opening tries), just retry
                if(m_handle < 0 && errno == ENOENT){
@@ -486,6 +491,15 @@ inline void shared_memory_object::priv_close()
    }
 }
 
+inline int shared_memory_object::eintr_aware_shm_open(const char* name, int oflag, ::mode_t mode)
+{
+   int shm_open_ret;
+   do {
+      shm_open_ret = shm_open(name, oflag, mode);
+   } while (shm_open_ret == -1 && errno == EINTR);
+   return shm_open_ret;
+}
+
 #endif
 
 //!A class that stores the name of a shared memory