Main Page   Class Hierarchy   Alphabetical List   Compound List   File List   Compound Members   File Members   Related Pages  

ACE_MMAP_Memory_Pool Class Reference

Make a memory pool that is based on <mmap(2)>. This implementation allows memory to be shared between processes. More...

#include <Memory_Pool.h>

Inheritance diagram for ACE_MMAP_Memory_Pool

Inheritance graph
[legend]
Collaboration diagram for ACE_MMAP_Memory_Pool:

Collaboration graph
[legend]
List of all members.

Public Types

typedef ACE_MMAP_Memory_Pool_Options OPTIONS

Public Methods

 ACE_MMAP_Memory_Pool (const ACE_TCHAR *backing_store_name = 0, const OPTIONS *options = 0)
 Initialize the pool.

virtual ~ACE_MMAP_Memory_Pool (void)
virtual void* init_acquire (size_t nbytes, size_t &rounded_bytes, int &first_time)
 Ask system for initial chunk of shared memory.

virtual void* acquire (size_t nbytes, size_t &rounded_bytes)
virtual int release (void)
 Instruct the memory pool to release all of its resources.

virtual int sync (ssize_t len = -1, int flags = MS_SYNC)
 Sync the memory region to the backing store starting at <this->base_addr_>.

virtual int sync (void *addr, size_t len, int flags = MS_SYNC)
 Sync the memory region to the backing store starting at .

virtual int protect (ssize_t len = -1, int prot = PROT_RDWR)
virtual int protect (void *addr, size_t len, int prot = PROT_RDWR)
 Change the protection of the pages of the mapped region to <prot> starting at up to <len> bytes.

virtual int seh_selector (void *)
virtual int remap (void *addr)
virtual void* base_addr (void) const
 Return the base address of this memory pool.

virtual void dump (void) const
 Dump the state of an object.


Public Attributes

 ACE_ALLOC_HOOK_DECLARE
 Declare the dynamic allocation hooks.


Protected Methods

virtual size_t round_up (size_t nbytes)
virtual int commit_backing_store_name (size_t rounded_bytes, off_t &map_size)
 Compute the new <map_size> of the backing store and commit the memory.

virtual int map_file (off_t map_size)
 Memory map the file up to <map_size> bytes.

virtual int handle_signal (int signum, siginfo_t *, ucontext_t *)
 Handle SIGSEGV and SIGBUS signals to remap shared memory properly.


Protected Attributes

ACE_Sig_Handler signal_handler_
 Handles SIGSEGV.

ACE_Mem_Map mmap_
 Memory-mapping object.

void* base_addr_
int flags_
 Flags passed into .

int write_each_page_
 Should we write a byte to each page to forceably allocate memory for this backing store?

off_t minimum_bytes_
 What the minimum bytes of the initial segment should be.

ACE_TCHAR backing_store_name_ [MAXPATHLEN + 1]
 Name of the backing store where the shared memory pool is kept.

int guess_on_fault_
LPSECURITY_ATTRIBUTES sa_
 Security attributes object, only used on NT.


Detailed Description

Make a memory pool that is based on <mmap(2)>. This implementation allows memory to be shared between processes.


Member Typedef Documentation

typedef ACE_MMAP_Memory_Pool_Options ACE_MMAP_Memory_Pool::OPTIONS
 


Constructor & Destructor Documentation

ACE_MMAP_Memory_Pool::ACE_MMAP_Memory_Pool ( const ACE_TCHAR * backing_store_name = 0,
const OPTIONS * options = 0 )
 

Initialize the pool.

ACE_INLINE ACE_MMAP_Memory_Pool::~ACE_MMAP_Memory_Pool ( void ) [virtual]
 


Member Function Documentation

void * ACE_MMAP_Memory_Pool::acquire ( size_t nbytes,
size_t & rounded_bytes ) [virtual]
 

Acquire at least <nbytes> from the memory pool. <rounded_bytes> is the actual number of bytes allocated. Also acquires an internal semaphore that ensures proper serialization of initialization across processes.

ACE_INLINE void * ACE_MMAP_Memory_Pool::base_addr ( void ) const [virtual]
 

Return the base address of this memory pool.

int ACE_MMAP_Memory_Pool::commit_backing_store_name ( size_t rounded_bytes,
off_t & map_size ) [protected, virtual]
 

Compute the new <map_size> of the backing store and commit the memory.

void ACE_MMAP_Memory_Pool::dump ( void ) const [virtual]
 

Dump the state of an object.

int ACE_MMAP_Memory_Pool::handle_signal ( int signum,
siginfo_t * siginfo,
ucontext_t * ucontext ) [protected, virtual]
 

Handle SIGSEGV and SIGBUS signals to remap shared memory properly.

Reimplemented from ACE_Event_Handler.

void * ACE_MMAP_Memory_Pool::init_acquire ( size_t nbytes,
size_t & rounded_bytes,
int & first_time ) [virtual]
 

Ask system for initial chunk of shared memory.

int ACE_MMAP_Memory_Pool::map_file ( off_t map_size ) [protected, virtual]
 

Memory map the file up to <map_size> bytes.

int ACE_MMAP_Memory_Pool::protect ( void * addr,
size_t len,
int prot = PROT_RDWR ) [virtual]
 

Change the protection of the pages of the mapped region to <prot> starting at up to <len> bytes.

int ACE_MMAP_Memory_Pool::protect ( ssize_t len = -1,
int prot = PROT_RDWR ) [virtual]
 

Change the protection of the pages of the mapped region to <prot> starting at <this->base_addr_> up to <len> bytes. If <len> == -1 then change protection of all pages in the mapped region.

int ACE_MMAP_Memory_Pool::release ( void ) [virtual]
 

Instruct the memory pool to release all of its resources.

int ACE_MMAP_Memory_Pool::remap ( void * addr ) [virtual]
 

Try to extend the virtual address space so that is now covered by the address mapping. The method succeeds and returns 0 if the backing store has adequate memory to cover this address. Otherwise, it returns -1. This method is typically called by a UNIX signal handler for SIGSEGV or a Win32 structured exception when another process has grown the backing store (and its mapping) and our process now incurs a fault because our mapping isn't in range (yet).

ACE_INLINE size_t ACE_MMAP_Memory_Pool::round_up ( size_t nbytes ) [protected, virtual]
 

int ACE_MMAP_Memory_Pool::seh_selector ( void * ep ) [virtual]
 

Win32 Structural exception selector. The return value decides how to handle memory pool related structural exceptions. Returns 1, 0, or , -1.

int ACE_MMAP_Memory_Pool::sync ( void * addr,
size_t len,
int flags = MS_SYNC ) [virtual]
 

Sync the memory region to the backing store starting at .

Reimplemented in ACE_Lite_MMAP_Memory_Pool.

int ACE_MMAP_Memory_Pool::sync ( ssize_t len = -1,
int flags = MS_SYNC ) [virtual]
 

Sync the memory region to the backing store starting at <this->base_addr_>.

Reimplemented in ACE_Lite_MMAP_Memory_Pool.


Member Data Documentation

ACE_MMAP_Memory_Pool::ACE_ALLOC_HOOK_DECLARE
 

Declare the dynamic allocation hooks.

ACE_TCHAR ACE_MMAP_Memory_Pool::backing_store_name_[MAXPATHLEN+1] [protected]
 

Name of the backing store where the shared memory pool is kept.

void * ACE_MMAP_Memory_Pool::base_addr_ [protected]
 

Base of mapped region. If this has the value of 0 then the OS is free to select any address to map the file, otherwise this value is what the OS must try to use to mmap the file.

int ACE_MMAP_Memory_Pool::flags_ [protected]
 

Flags passed into .

int ACE_MMAP_Memory_Pool::guess_on_fault_ [protected]
 

Try to remap without knowing the faulting address. This parameter is ignored on platforms that know the faulting address (UNIX with SI_ADDR and Win32).

off_t ACE_MMAP_Memory_Pool::minimum_bytes_ [protected]
 

What the minimum bytes of the initial segment should be.

ACE_Mem_Map ACE_MMAP_Memory_Pool::mmap_ [protected]
 

Memory-mapping object.

LPSECURITY_ATTRIBUTES ACE_MMAP_Memory_Pool::sa_ [protected]
 

Security attributes object, only used on NT.

ACE_Sig_Handler ACE_MMAP_Memory_Pool::signal_handler_ [protected]
 

Handles SIGSEGV.

int ACE_MMAP_Memory_Pool::write_each_page_ [protected]
 

Should we write a byte to each page to forceably allocate memory for this backing store?


The documentation for this class was generated from the following files:
Generated at Fri Oct 5 07:03:01 2001 for ACE by doxygen1.2.3 written by Dimitri van Heesch, © 1997-2000