dep/ACE_wrappers/ace/Sbrk_Memory_Pool.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file     Sbrk_Memory_Pool.h
   6  *
   7  *  $Id: Sbrk_Memory_Pool.h 80826 2008-03-04 14:51:23Z wotte $
   8  *
   9  *  @author Dougls C. Schmidt <schmidt@cs.wustl.edu>
  10  *  @author Prashant Jain <pjain@cs.wustl.edu>
  11  */
  12 //=============================================================================
  13
  14 #ifndef ACE_SBRK_MEMORY_POOL_H
  15 #define ACE_SBRK_MEMORY_POOL_H
  16
  17 #include /**/ "ace/pre.h"
  18
  19 #include /**/ "ace/ACE_export.h"
  20
  21 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  22 # pragma once
  23 #endif /* ACE_LACKS_PRAGMA_ONCE */
  24
  25 #if !defined (ACE_LACKS_SBRK)
  26
  27 #include "ace/ACE.h"
  28 #include "ace/os_include/sys/os_mman.h"
  29
  30
  31 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  32
  33 /**
  34  * @class ACE_Sbrk_Memory_Pool_Options
  35  *
  36  * @brief Helper class for Sbrk Memory Pool constructor options.
  37  *
  38  * This should be a nested class, but that breaks too many
  39  * compilers.
  40  */
  41 class ACE_Export ACE_Sbrk_Memory_Pool_Options
  42 {
  43 };
  44
  45 /**
  46  * @class ACE_Sbrk_Memory_Pool
  47  *
  48  * @brief Make a memory pool that is based on <sbrk(2)>.
  49  */
  50 class ACE_Export ACE_Sbrk_Memory_Pool
  51 {
  52 public:
  53   typedef ACE_Sbrk_Memory_Pool_Options OPTIONS;
  54
  55   /// Initialize the pool.
  56   ACE_Sbrk_Memory_Pool (const ACE_TCHAR *backing_store_name = 0,
  57                         const OPTIONS *options = 0);
  58
  59   virtual ~ACE_Sbrk_Memory_Pool (void);
  60
  61   // = Implementor operations.
  62   /// Ask system for initial chunk of local memory.
  63   virtual void *init_acquire (size_t nbytes,
  64                               size_t &rounded_bytes,
  65                               int &first_time);
  66
  67   /// Acquire at least @a nbytes from the memory pool. @a rounded_bytes is
  68   /// the actual number of bytes allocated.
  69   virtual void *acquire (size_t nbytes,
  70                          size_t &rounded_bytes);
  71
  72   /// Instruct the memory pool to release all of its resources.
  73   virtual int release (int destroy = 1);
  74
  75   /**
  76    * Sync @a len bytes of the memory region to the backing store
  77    * starting at @c this->base_addr_.  If @a len == -1 then sync the
  78    * whole region.
  79    */
  80   virtual int sync (ssize_t len = -1, int flags = MS_SYNC);
  81
  82   /// Sync @a len bytes of the memory region to the backing store
  83   /// starting at @a addr.
  84   virtual int sync (void *addr, size_t len, int flags = MS_SYNC);
  85
  86   /**
  87    * Change the protection of the pages of the mapped region to @a prot
  88    * starting at @c this->base_addr_ up to @a len bytes.  If @a len == -1
  89    * then change protection of all pages in the mapped region.
  90    */
  91   virtual int protect (ssize_t len = -1, int prot = PROT_RDWR);
  92
  93   /// Change the protection of the pages of the mapped region to @a prot
  94   /// starting at @a addr up to @a len bytes.
  95   virtual int protect (void *addr, size_t len, int prot = PROT_RDWR);
  96
  97   /// Dump the state of an object.
  98   virtual void dump (void) const;
  99
 100   /// Return the base address of this memory pool, 0 if base_addr
 101   /// never changes.
 102   virtual void *base_addr (void) const;
 103
 104   /// Declare the dynamic allocation hooks.
 105   ACE_ALLOC_HOOK_DECLARE;
 106
 107 protected:
 108   /// Implement the algorithm for rounding up the request to an
 109   /// appropriate chunksize.
 110   virtual size_t round_up (size_t nbytes);
 111 };
 112
 113 ACE_END_VERSIONED_NAMESPACE_DECL
 114
 115 #endif /* !ACE_LACKS_SBRK */
 116
 117 #include /**/ "ace/post.h"
 118 #endif /* ACE_SBRK_MEMORY_POOL_H */