/* -*- C++ -*- */ //============================================================================= /** * @file Memory_Pool.h * * $Id$ * * @author Dougls C. Schmidt and Prashant Jain */ //============================================================================= #ifndef ACE_MEMORY_POOL_H #define ACE_MEMORY_POOL_H #include "ace/pre.h" #include "ace/ACE.h" #if !defined (ACE_LACKS_PRAGMA_ONCE) # pragma once #endif /* ACE_LACKS_PRAGMA_ONCE */ #include "ace/Event_Handler.h" #include "ace/Signal.h" #include "ace/Mem_Map.h" #if !defined (ACE_WIN32) #include "ace/SV_Semaphore_Complex.h" #endif /* !ACE_WIN32 */ #include "ace/Unbounded_Set.h" #if !defined (ACE_LACKS_SBRK) /** * @class ACE_Sbrk_Memory_Pool_Options * * @brief Helper class for Sbrk Memory Pool constructor options. * * This should be a nested class, but that breaks too many * compilers. */ class ACE_Export ACE_Sbrk_Memory_Pool_Options { }; /** * @class ACE_Sbrk_Memory_Pool * * @brief Make a memory pool that is based on . */ class ACE_Export ACE_Sbrk_Memory_Pool { public: typedef ACE_Sbrk_Memory_Pool_Options OPTIONS; /// Initialize the pool. ACE_Sbrk_Memory_Pool (const ACE_TCHAR *backing_store_name = 0, const OPTIONS *options = 0); virtual ~ACE_Sbrk_Memory_Pool (void); // = Implementor operations. /// Ask system for initial chunk of local memory. virtual void *init_acquire (size_t nbytes, size_t &rounded_bytes, int &first_time); /// Acquire at least NBYTES from the memory pool. ROUNDED_BYTES is /// the actual number of bytes allocated. virtual void *acquire (size_t nbytes, size_t &rounded_bytes); /// Instruct the memory pool to release all of its resources. virtual int release (void); /** * Sync bytes of the memory region to the backing store * starting at base_addr_>. If == -1 then sync the * whole region. */ virtual int sync (ssize_t len = -1, int flags = MS_SYNC); /// Sync bytes of the memory region to the backing store /// starting at . virtual int sync (void *addr, size_t len, int flags = MS_SYNC); /** * Change the protection of the pages of the mapped region to * starting at base_addr_> up to bytes. If == -1 * then change protection of all pages in the mapped region. */ virtual int protect (ssize_t len = -1, int prot = PROT_RDWR); /// Change the protection of the pages of the mapped region to /// starting at up to bytes. virtual int protect (void *addr, size_t len, int prot = PROT_RDWR); /// Dump the state of an object. virtual void dump (void) const; /// Return the base address of this memory pool, 0 if base_addr /// never changes. virtual void *base_addr (void) const; /// Declare the dynamic allocation hooks. ACE_ALLOC_HOOK_DECLARE; protected: /// Implement the algorithm for rounding up the request to an /// appropriate chunksize. virtual size_t round_up (size_t nbytes); }; #endif /* !ACE_LACKS_SBRK */ #if !defined (ACE_LACKS_SYSV_SHMEM) /** * @class ACE_Shared_Memory_Pool_Options * * @brief Helper class for Shared Memory Pool constructor options. * * This should be a nested class, but that breaks too many * compilers. */ class ACE_Export ACE_Shared_Memory_Pool_Options { public: /// Initialization method. ACE_Shared_Memory_Pool_Options (const char *base_addr = ACE_DEFAULT_BASE_ADDR, size_t max_segments = ACE_DEFAULT_MAX_SEGMENTS, size_t file_perms = ACE_DEFAULT_FILE_PERMS, off_t minimum_bytes = 0, size_t segment_size = ACE_DEFAULT_SEGMENT_SIZE); /// Base address of the memory-mapped backing store. const char *base_addr_; /// Number of shared memory segments to allocate. size_t max_segments_; /// What the minimum bytes of the initial segment should be. off_t minimum_bytes_; /// File permissions to use when creating/opening a segment. size_t file_perms_; /// Shared memory segment size. size_t segment_size_; }; /** * @class ACE_Shared_Memory_Pool * * @brief Make a memory pool that is based on System V shared memory * (shmget(2) etc.). This implementation allows memory to be * shared between processes. If your platform doesn't support * System V shared memory (e.g., Win32 and many RTOS platforms * do not) then you should use instead of this * class. In fact, you should probably use on * platforms that *do* support System V shared memory since it * provides more powerful features, such as persistent backing store * and greatly scalability. */ class ACE_Export ACE_Shared_Memory_Pool : public ACE_Event_Handler { public: typedef ACE_Shared_Memory_Pool_Options OPTIONS; /// Initialize the pool. ACE_Shared_Memory_Pool (const ACE_TCHAR *backing_store_name = 0, const OPTIONS *options = 0); virtual ~ACE_Shared_Memory_Pool (void); /// Ask system for initial chunk of local memory. virtual void *init_acquire (size_t nbytes, size_t &rounded_bytes, int &first_time); /** * 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 Memory_Pool * initialization across processes. */ virtual void *acquire (size_t nbytes, size_t &rounded_bytes); /// Instruct the memory pool to release all of its resources. virtual int release (void); /// Sync the memory region to the backing store starting at /// base_addr_>. virtual int sync (ssize_t len = -1, int flags = MS_SYNC); /// Sync the memory region to the backing store starting at . virtual int sync (void *addr, size_t len, int flags = MS_SYNC); /** * Change the protection of the pages of the mapped region to * starting at base_addr_> up to bytes. If == -1 * then change protection of all pages in the mapped region. */ virtual int protect (ssize_t len = -1, int prot = PROT_RDWR); /// Change the protection of the pages of the mapped region to /// starting at up to bytes. virtual int protect (void *addr, size_t len, int prot = PROT_RDWR); /// Return the base address of this memory pool, 0 if base_addr /// never changes. virtual void *base_addr (void) const; /// Dump the state of an object. virtual void dump (void) const; /// Declare the dynamic allocation hooks. ACE_ALLOC_HOOK_DECLARE; protected: /// Implement the algorithm for rounding up the request to an /// appropriate chunksize. virtual size_t round_up (size_t nbytes); /** * Commits a new shared memory segment if necessary after an * or a signal. is set to the new offset into * the backing store. */ virtual int commit_backing_store_name (size_t rounded_bytes, off_t &offset); /// Keeps track of all the segments being used. struct SHM_TABLE { /// Shared memory segment key. key_t key_; /// Shared memory segment internal id. int shmid_; /// Is the segment currently used.; int used_; }; /** * Base address of the shared memory segment. If this has the value * of 0 then the OS is free to select any address, otherwise this * value is what the OS must try to use to map the shared memory * segment. */ void *base_addr_; /// File permissions to use when creating/opening a segment. size_t file_perms_; /// Number of shared memory segments in the table. size_t max_segments_; /// What the minimim bytes of the initial segment should be. off_t minimum_bytes_; /// Shared memory segment size. size_t segment_size_; /// Base shared memory key for the segment. key_t base_shm_key_; /// Find the segment that contains the @a searchPtr virtual int find_seg (const void *const searchPtr, off_t &offset, size_t &counter); /// Determine how much memory is currently in use. virtual int in_use (off_t &offset, size_t &counter); /// Handles SIGSEGV. ACE_Sig_Handler signal_handler_; /// Handle SIGSEGV and SIGBUS signals to remap shared memory /// properly. virtual int handle_signal (int signum, siginfo_t *, ucontext_t *); }; #endif /* !ACE_LACKS_SYSV_SHMEM */ /** * @class ACE_Local_Memory_Pool_Options * * @brief Helper class for Local Memory Pool constructor options. * * This should be a nested class, but that breaks too many * compilers. */ class ACE_Export ACE_Local_Memory_Pool_Options { }; /** * @class ACE_Local_Memory_Pool * * @brief Make a memory pool that is based on C++ new/delete. This is * useful for integrating existing components that use new/delete * into the ACE Malloc scheme... */ class ACE_Export ACE_Local_Memory_Pool { public: typedef ACE_Local_Memory_Pool_Options OPTIONS; /// Initialize the pool. ACE_Local_Memory_Pool (const ACE_TCHAR *backing_store_name = 0, const OPTIONS *options = 0); virtual ~ACE_Local_Memory_Pool (void); /// Ask system for initial chunk of local memory. virtual void *init_acquire (size_t nbytes, size_t &rounded_bytes, int &first_time); /// Acquire at least NBYTES from the memory pool. ROUNDED_BYTES is /// the actual number of bytes allocated. virtual void *acquire (size_t nbytes, size_t &rounded_bytes); /// Instruct the memory pool to release all of its resources. virtual int release (void); /** * Sync bytes of the memory region to the backing store * starting at base_addr_>. If == -1 then sync the * whole region. */ virtual int sync (ssize_t len = -1, int flags = MS_SYNC); /// Sync bytes of the memory region to the backing store /// starting at . virtual int sync (void *addr, size_t len, int flags = MS_SYNC); /** * Change the protection of the pages of the mapped region to * starting at base_addr_> up to bytes. If == -1 * then change protection of all pages in the mapped region. */ virtual int protect (ssize_t len = -1, int prot = PROT_RDWR); /// Change the protection of the pages of the mapped region to /// starting at up to bytes. virtual int protect (void *addr, size_t len, int prot = PROT_RDWR); #if defined (ACE_WIN32) /** * Win32 Structural exception selector. The return value decides * how to handle memory pool related structural exceptions. Returns * 1, 0, or , -1. */ virtual int seh_selector (void *); #endif /* ACE_WIN32 */ /** * Try to extend the virtual address space so that is now * covered by the address mapping. Always returns 0 since we can't * remap a local memory pool. */ virtual int remap (void *addr); /// Return the base address of this memory pool, 0 if base_addr /// never changes. virtual void *base_addr (void) const; /// Dump the state of an object. virtual void dump (void) const; /// Declare the dynamic allocation hooks. ACE_ALLOC_HOOK_DECLARE; protected: /// List of memory that we have allocated. ACE_Unbounded_Set allocated_chunks_; /// Implement the algorithm for rounding up the request to an /// appropriate chunksize. virtual size_t round_up (size_t nbytes); }; /** * @class ACE_MMAP_Memory_Pool_Options * * @brief Helper class for MMAP Memory Pool constructor options. * * This should be a nested class, but that breaks too many * compilers. */ class ACE_Export ACE_MMAP_Memory_Pool_Options { public: enum { /** * The base address from the first call to mmap will be used for subsequent * calls to mmap. */ FIRSTCALL_FIXED = 0, /** * The base address specified in base_addr will be used in all calls to * mmap. */ ALWAYS_FIXED = 1, /** * The base address will be selected by the OS for each call to mmap. * Caution should be used with this mode since a call that requires the * backing store to grow may change pointers that are cached by the * application. */ NEVER_FIXED = 2 }; // = Initialization method. ACE_MMAP_Memory_Pool_Options (const void *base_addr = ACE_DEFAULT_BASE_ADDR, int use_fixed_addr = ALWAYS_FIXED, int write_each_page = 1, off_t minimum_bytes = 0, u_int flags = 0, int guess_on_fault = 1, LPSECURITY_ATTRIBUTES sa = 0); /// Base address of the memory-mapped backing store. const void *base_addr_; /** * Determines whether we set or if mmap(2) selects it * FIRSTCALL_FIXED The base address from the first call to mmap * will be used for subsequent calls to mmap * ALWAYS_FIXED The base address specified in base_addr will be * used in all calls to mmap. * NEVER_FIXED The base address will be selected by the OS for * each call to mmap. Caution should be used with * this mode since a call that requires the backing * store to grow may change pointers that are * cached by the application. */ int use_fixed_addr_; /// Should each page be written eagerly to avoid surprises later /// on? int write_each_page_; /// What the minimim bytes of the initial segment should be. off_t minimum_bytes_; /// Any special flags that need to be used for . u_int flags_; /** * 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). */ int guess_on_fault_; /// Pointer to a security attributes object. Only used on NT. LPSECURITY_ATTRIBUTES sa_; }; /** * @class ACE_MMAP_Memory_Pool * * @brief Make a memory pool that is based on . This * implementation allows memory to be shared between processes. */ class ACE_Export ACE_MMAP_Memory_Pool : public ACE_Event_Handler { public: typedef ACE_MMAP_Memory_Pool_Options OPTIONS; // = Initialization and termination methods. /// Initialize the pool. ACE_MMAP_Memory_Pool (const ACE_TCHAR *backing_store_name = 0, const OPTIONS *options = 0); /// Destructor. virtual ~ACE_MMAP_Memory_Pool (void); /// Ask system for initial chunk of shared memory. virtual void *init_acquire (size_t nbytes, size_t &rounded_bytes, int &first_time); /** * Acquire at least from the memory pool. * is the actual number of bytes allocated. Also acquires an * internal semaphore that ensures proper serialization of * initialization across processes. */ virtual void *acquire (size_t nbytes, size_t &rounded_bytes); /// Instruct the memory pool to release all of its resources. virtual int release (void); /// Sync the memory region to the backing store starting at /// base_addr_>. virtual int sync (ssize_t len = -1, int flags = MS_SYNC); /// Sync the memory region to the backing store starting at . virtual int sync (void *addr, size_t len, int flags = MS_SYNC); /** * Change the protection of the pages of the mapped region to * starting at base_addr_> up to bytes. If == -1 * then change protection of all pages in the mapped region. */ virtual int protect (ssize_t len = -1, int prot = PROT_RDWR); /// Change the protection of the pages of the mapped region to /// starting at up to bytes. virtual int protect (void *addr, size_t len, int prot = PROT_RDWR); #if defined (ACE_WIN32) /** * Win32 Structural exception selector. The return value decides * how to handle memory pool related structural exceptions. Returns * 1, 0, or , -1. */ virtual int seh_selector (void *); #endif /* ACE_WIN32 */ /** * 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). */ virtual int remap (void *addr); /// Return the base address of this memory pool. virtual void *base_addr (void) const; /// Dump the state of an object. virtual void dump (void) const; /// Declare the dynamic allocation hooks. ACE_ALLOC_HOOK_DECLARE; protected: /// Implement the algorithm for rounding up the request to an /// appropriate chunksize. virtual size_t round_up (size_t nbytes); /// Compute the new of the backing store and commit the /// memory. virtual int commit_backing_store_name (size_t rounded_bytes, off_t &map_size); /// Memory map the file up to bytes. virtual int map_file (off_t map_size); /// Handle SIGSEGV and SIGBUS signals to remap shared memory /// properly. virtual int handle_signal (int signum, siginfo_t *, ucontext_t *); /// Handles SIGSEGV. ACE_Sig_Handler signal_handler_; /// Memory-mapping object. ACE_Mem_Map mmap_; /** * 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. */ void *base_addr_; /// Must we use the or can we let mmap(2) select it? int use_fixed_addr_; /// Flags passed into . int flags_; /// Should we write a byte to each page to forceably allocate memory /// for this backing store? int write_each_page_; /// What the minimum bytes of the initial segment should be. off_t minimum_bytes_; /// Name of the backing store where the shared memory pool is kept. ACE_TCHAR backing_store_name_[MAXPATHLEN + 1]; /** * 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). */ int guess_on_fault_; /// Security attributes object, only used on NT. LPSECURITY_ATTRIBUTES sa_; }; /** * @class ACE_Lite_MMAP_Memory_Pool * * @brief Make a ``lighter-weight'' memory pool based . * * This implementation allows memory to be shared between * processes. However, unlike the * the methods are no-ops, which means that we don't pay * for the price of flushing the memory to the backing store on * every update. Naturally, this trades off increased * performance for less reliability if the machine crashes. */ class ACE_Export ACE_Lite_MMAP_Memory_Pool : public ACE_MMAP_Memory_Pool { public: /// Initialize the pool. ACE_Lite_MMAP_Memory_Pool (const ACE_TCHAR *backing_store_name = 0, const OPTIONS *options = 0); /// Destructor. virtual ~ACE_Lite_MMAP_Memory_Pool (void); /// Overwrite the default sync behavior with no-op virtual int sync (ssize_t len = -1, int flags = MS_SYNC); /// Overwrite the default sync behavior with no-op virtual int sync (void *addr, size_t len, int flags = MS_SYNC); }; #if defined (ACE_WIN32) /** * @class ACE_Pagefile_Memory_Pool_Options * * @brief Helper class for Pagefile Memory Pool constructor options. * * This should be a nested class, but that breaks too many * compilers. */ class ACE_Export ACE_Pagefile_Memory_Pool_Options { public: /// Initialization method. ACE_Pagefile_Memory_Pool_Options (void *base_addr = ACE_DEFAULT_PAGEFILE_POOL_BASE, size_t max_size = ACE_DEFAULT_PAGEFILE_POOL_SIZE); /// Base address of the memory-mapped backing store. void *base_addr_; /// Maximum size the pool may grow. size_t max_size_; }; /** * @class ACE_Pagefile_Memory_Pool * * @brief Make a memory pool that is based on "anonymous" memory * regions allocated from the Win32 page file. */ class ACE_Export ACE_Pagefile_Memory_Pool { public: typedef ACE_Pagefile_Memory_Pool_Options OPTIONS; /// Initialize the pool. ACE_Pagefile_Memory_Pool (const ACE_TCHAR *backing_store_name = 0, const OPTIONS *options = 0); /// Ask system for initial chunk of shared memory. void *init_acquire (size_t nbytes, size_t &rounded_bytes, int &first_time); /// Acquire at least from the memory pool. /// is the actual number of bytes allocated. void *acquire (size_t nbytes, size_t &rounded_bytes); /// Instruct the memory pool to release all of its resources. int release (void); /** * Win32 Structural exception selector. The return value decides * how to handle memory pool related structural exceptions. Returns * 1, 0, or , -1. */ virtual int seh_selector (void *); /** * 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 an * exception handler for 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). */ int remap (void *addr); /// Round up to system page size. size_t round_to_page_size (size_t nbytes); /// Round up to the chunk size required by the operation system size_t round_to_chunk_size (size_t nbytes); // = Don't need this methods here ... int sync (ssize_t = -1, int = MS_SYNC); int sync (void *, size_t, int = MS_SYNC); int protect (ssize_t = -1, int = PROT_RDWR); int protect (void *, size_t, int = PROT_RDWR); /// Return the base address of this memory pool, 0 if base_addr /// never changes. virtual void *base_addr (void) const; void dump (void) const {} protected: /** * Map portions or the entire pool into the local virtual address * space. To do this, we compute the new of the * backing store and commit the memory. */ int map (int &firstTime, int appendBytes = 0); /// Release the mapping. int unmap (void); private: /** * @class Control_Block * * @brief Attributes that are meaningful in local storage only. */ class Control_Block { public: /// Required base address void *req_base_; /// Base address returned from system call void *mapped_base_; /** * @class Shared_Control_Block * * @brief Pool statistics */ class Shared_Control_Block { public: /// Maximum size the pool may grow size_t max_size_; /// Size of mapped shared memory segment int mapped_size_; /// Offset to mapped but not yet acquired address space int free_offset_; /// Size of mapped but not yet acquired address space int free_size_; }; Shared_Control_Block sh_; }; // 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. /// Description of what our process mapped. Control_Block local_cb_; /// Shared memory pool statistics. Control_Block *shared_cb_; /// File mapping handle. ACE_HANDLE object_handle_; /// System page size. size_t page_size_; /// Name of the backing store where the shared memory pool is kept. ACE_TCHAR backing_store_name_[MAXPATHLEN]; }; #endif /* ACE_WIN32 */ #if defined (__ACE_INLINE__) #include "ace/Memory_Pool.i" #endif /* __ACE_INLINE__ */ #include "ace/post.h" #endif /* ACE_MEMORY_POOL_H */