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>

Inheritance diagram for ACE_MMAP_Memory_Pool:

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Collaboration diagram for ACE_MMAP_Memory_Pool:

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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 (ssize_t len=-1, 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 (ssize_t len=-1, 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.

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, off_t &map_size)
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 *)

Protected Attributes

ACE_Sig_Handler signal_handler_
 Handles SIGSEGV.
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>.
int write_each_page_
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.
mode_t file_mode_
 Protection mode for mmaped file.

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_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,
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 ,
ucontext_t
[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 addr 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 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 *   )  [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 addr.

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.

mode_t ACE_MMAP_Memory_Pool::file_mode_ [protected]
 

Protection mode for mmaped file.

int ACE_MMAP_Memory_Pool::flags_ [protected]
 

Flags passed into <ACE_OS::mmap>.

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::use_fixed_addr_ [protected]
 

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

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 on Wed Nov 23 15:49:20 2005 for ACE by  doxygen 1.4.5