ACE/ace/Local_Memory_Pool.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file     Local_Memory_Pool.h
   6  *
   7  *  @author Dougls C. Schmidt <d.schmidt@vanderbilt.edu>
   8  *  @author Prashant Jain <pjain@cs.wustl.edu>
   9  */
  10 //=============================================================================
  11
  12 #ifndef ACE_LOCAL_MEMORY_POOL_H
  13 #define ACE_LOCAL_MEMORY_POOL_H
  14 #include /**/ "ace/pre.h"
  15
  16 #include "ace/os_include/sys/os_mman.h"   /* Need PROT_RDWR */
  17 #include "ace/ACE.h"
  18
  19 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  20 # pragma once
  21 #endif /* ACE_LACKS_PRAGMA_ONCE */
  22
  23 #include "ace/Unbounded_Set.h"
  24
  25 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  26
  27 /**
  28  * @class ACE_Local_Memory_Pool_Options
  29  *
  30  * @brief Helper class for Local Memory Pool constructor options.
  31  *
  32  * This should be a nested class, but that breaks too many
  33  * compilers.
  34  */
  35 class ACE_Export ACE_Local_Memory_Pool_Options
  36 {
  37 };
  38
  39 /**
  40  * @class ACE_Local_Memory_Pool
  41  *
  42  * @brief Make a memory pool that is based on C++ new/delete.  This is
  43  * useful for integrating existing components that use new/delete
  44  * into the ACE Malloc scheme...
  45  */
  46 class ACE_Export ACE_Local_Memory_Pool
  47 {
  48 public:
  49   typedef ACE_Local_Memory_Pool_Options OPTIONS;
  50
  51   /// Initialize the pool.
  52   ACE_Local_Memory_Pool (const ACE_TCHAR *backing_store_name = 0,
  53                          const OPTIONS *options = 0);
  54
  55   virtual ~ACE_Local_Memory_Pool ();
  56
  57   /// Ask system for initial chunk of local memory.
  58   virtual void *init_acquire (size_t nbytes,
  59                               size_t &rounded_bytes,
  60                               int &first_time);
  61
  62   /// Acquire at least @a nbytes from the memory pool. @a rounded_bytes is
  63   /// the actual number of bytes allocated.
  64   virtual void *acquire (size_t nbytes,
  65                          size_t &rounded_bytes);
  66
  67   /// Instruct the memory pool to release all of its resources.
  68   virtual int release (int destroy = 1);
  69
  70   /**
  71    * Sync @a len bytes of the memory region to the backing store
  72    * starting at <this->base_addr_>.  If @a len == -1 then sync the
  73    * whole region.
  74    */
  75   virtual int sync (ssize_t len = -1, int flags = MS_SYNC);
  76
  77   /// Sync @a len bytes of the memory region to the backing store
  78   /// starting at @a add_.
  79   virtual int sync (void *addr, size_t len, int flags = MS_SYNC);
  80
  81   /**
  82    * Change the protection of the pages of the mapped region to @a prot
  83    * starting at <this->base_addr_> up to @a len bytes.  If @a len == -1
  84    * then change protection of all pages in the mapped region.
  85    */
  86   virtual int protect (ssize_t len = -1, int prot = PROT_RDWR);
  87
  88   /// Change the protection of the pages of the mapped region to @a prot
  89   /// starting at @a addr up to @a len bytes.
  90   virtual int protect (void *addr, size_t len, int prot = PROT_RDWR);
  91
  92 #if defined (ACE_WIN32)
  93   /**
  94    * Win32 Structural exception selector.  The return value decides
  95    * how to handle memory pool related structural exceptions.  Returns
  96    * 1, 0, or , -1.
  97    */
  98   virtual int seh_selector (void *);
  99 #endif /* ACE_WIN32 */
 100
 101   /**
 102    * Try to extend the virtual address space so that @a addr is now
 103    * covered by the address mapping.  Always returns 0 since we can't
 104    * remap a local memory pool.
 105    */
 106   virtual int remap (void *addr);
 107
 108   /// Return the base address of this memory pool, 0 if base_addr
 109   /// never changes.
 110   virtual void *base_addr () const;
 111
 112   /// Dump the state of an object.
 113   virtual void dump () const;
 114
 115   /// Declare the dynamic allocation hooks.
 116   ACE_ALLOC_HOOK_DECLARE;
 117
 118 protected:
 119   /// List of memory that we have allocated.
 120   ACE_Unbounded_Set<char *> allocated_chunks_;
 121
 122   /// Implement the algorithm for rounding up the request to an
 123   /// appropriate chunksize.
 124   virtual size_t round_up (size_t nbytes);
 125 };
 126
 127 ACE_END_VERSIONED_NAMESPACE_DECL
 128
 129 #include /**/ "ace/post.h"
 130 #endif /* ACE_LOCAL_MEMORY_POOL_H */