ACE  6.1.0
Public Types | Public Member Functions | Public Attributes | Protected Member Functions | Protected Attributes
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 <MMAP_Memory_Pool.h>

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List of all members.

Public Types

typedef
ACE_MMAP_Memory_Pool_Options 
OPTIONS

Public Member Functions

 ACE_MMAP_Memory_Pool (const ACE_TCHAR *backing_store_name=0, const OPTIONS *options=0)
 Initialize the pool.
virtual ~ACE_MMAP_Memory_Pool (void)
 Destructor.
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 (int destroy=1)
 Instruct the memory pool to release all of its resources.
virtual int sync (size_t len, int flags=MS_SYNC)
virtual int sync (int flags=MS_SYNC)
virtual int sync (void *addr, size_t len, int flags=MS_SYNC)
 Sync the memory region to the backing store starting at addr.
virtual int protect (size_t len, int prot=PROT_RDWR)
virtual int protect (int prot=PROT_RDWR)
virtual int protect (void *addr, size_t len, int prot=PROT_RDWR)
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.
ACE_Mem_Map const & mmap (void) const
 Get reference to underlying ACE_Mem_Map object.
ACE_Mem_Mapmmap (void)
 Get reference to underlying ACE_Mem_Map object.

Public Attributes

 ACE_ALLOC_HOOK_DECLARE
 Declare the dynamic allocation hooks.

Protected Member Functions

virtual size_t round_up (size_t nbytes)
virtual int commit_backing_store_name (size_t rounded_bytes, size_t &map_size)
virtual int map_file (size_t map_size)
 Memory map the file up to map_size bytes.

Protected Attributes

ACE_Mem_Map mmap_
 Memory-mapping object.
void * base_addr_
int use_fixed_addr_
 Must we use the base_addr_ or can we let mmap(2) select it?
int flags_
 Flags passed into ACE_OS::mmap().
bool write_each_page_
size_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.
bool guess_on_fault_
LPSECURITY_ATTRIBUTES sa_
 Security attributes object, only used on NT.
mode_t file_mode_
 Protection mode for mmaped file.
bool install_signal_handler_
 Should we install a signal handler.

Detailed Description

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


Member Typedef Documentation


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_MMAP_Memory_Pool::~ACE_MMAP_Memory_Pool ( void  ) [virtual]

Destructor.


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 ACE_MMAP_Memory_Pool initialization across processes.

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,
size_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.

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 ( size_t  map_size) [protected, virtual]

Memory map the file up to map_size bytes.

ACE_Mem_Map const & ACE_MMAP_Memory_Pool::mmap ( void  ) const [inline]

Get reference to underlying ACE_Mem_Map object.

ACE_Mem_Map & ACE_MMAP_Memory_Pool::mmap ( void  ) [inline]

Get reference to underlying ACE_Mem_Map object.

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

Change the protection of all the pages of the mapped region to prot starting at this->base_addr_.

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 addr up to len bytes.

int ACE_MMAP_Memory_Pool::release ( int  destroy = 1) [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 addr 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).

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

Implement the algorithm for rounding up the request to an appropriate chunksize.

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 ( size_t  len,
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.

int ACE_MMAP_Memory_Pool::sync ( int  flags = MS_SYNC) [virtual]

Sync the memory region to the backing store starting at this->base_addr_. Will sync as much as the backing file allows.

Reimplemented in ACE_Lite_MMAP_Memory_Pool.

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 addr.

Sync len bytes of the memory region to the backing store starting at <addr_>.

Reimplemented in ACE_Lite_MMAP_Memory_Pool.


Member Data Documentation

Declare the dynamic allocation hooks.

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

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.

Protection mode for mmaped file.

Flags passed into ACE_OS::mmap().

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).

Should we install a signal handler.

What the minimum bytes of the initial segment should be.

Memory-mapping object.

LPSECURITY_ATTRIBUTES ACE_MMAP_Memory_Pool::sa_ [protected]

Security attributes object, only used on NT.

Must we use the base_addr_ or can we let mmap(2) select it?

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:
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