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Diffstat (limited to 'ace/DLL_Manager.h')
| -rw-r--r-- | ace/DLL_Manager.h | 270 |
1 files changed, 0 insertions, 270 deletions
diff --git a/ace/DLL_Manager.h b/ace/DLL_Manager.h deleted file mode 100644 index 2bde7161251..00000000000 --- a/ace/DLL_Manager.h +++ /dev/null @@ -1,270 +0,0 @@ -// -*- C++ -*- - -//============================================================================= -/** - * @file DLL_Manager.h - * - * $Id$ - * - * @author Don Hinton <dhinton@ieee.org> - */ -//============================================================================= - - -#ifndef ACE_DLL_MANAGER_H -#define ACE_DLL_MANAGER_H -#include /**/ "ace/pre.h" - -#include "ace/ACE_export.h" - -#if !defined (ACE_LACKS_PRAGMA_ONCE) -# pragma once -#endif /* ACE_LACKS_PRAGMA_ONCE */ - -#include "ace/Auto_Ptr.h" -#include "ace/Containers_T.h" -#include "ace/SStringfwd.h" -#include "ace/os_include/os_dlfcn.h" - -#if defined (ACE_MT_SAFE) && (ACE_MT_SAFE != 0) -# include "ace/Thread_Mutex.h" -#endif /* ACE_MT_SAFE */ - -#define ACE_DEFAULT_DLL_MANAGER_SIZE 1024 - - -ACE_BEGIN_VERSIONED_NAMESPACE_DECL - -/** - * @class ACE_DLL_Handle - * - * @brief Provides an abstract interface for handling various DLL - * operations. - * - * This class is an wrapper over the various methods for utilizing - * a dynamically linked library (DLL), which is called a shared - * library on some platforms. It is refcounted and managed by - * ACE_DLL_Manager, so there will only be a single instance of this - * class for each dll loaded, no matter how many instances of ACE_DLL - * an application has open. Operations <open>, <close>, and - * <symbol> have been implemented to help opening/closing and - * extracting symbol information from a DLL, respectively. - * - * Most of this class came from the original ACE_DLL class. - * ACE_DLL is now just an interface that passed all it's calls - * either directly or via ACE_DLL_Manager to this class for - * execution. - * - */ -class ACE_DLL_Handle -{ -public: - - /// Default construtor. - ACE_DLL_Handle (void); - - /// Destructor. - ~ACE_DLL_Handle (void); - - /// Returns the name of the shared library (without prefixes or suffixes). - const ACE_TCHAR *dll_name () const; - - /** - * This method opens and dynamically links @a dll_name. The default - * mode is <RTLD_LAZY>, which loads identifier symbols but not the - * symbols for functions, which are loaded dynamically on-demand. - * Other supported modes include: <RTLD_NOW>, which performs all - * necessary relocations when @a dll_name is first loaded and - * <RTLD_GLOBAL>, which makes symbols available for relocation - * processing of any other DLLs. Returns -1 on failure and 0 on - * success. - */ - int open (const ACE_TCHAR *dll_name, - int open_mode, - ACE_SHLIB_HANDLE handle); - - /// Call to close the DLL object. If unload = 0, it only decrements - /// the refcount, but if unload = 1, then it will actually unload - /// the library when the refcount == 0; - int close (int unload = 0); - - /// Return the current refcount. - sig_atomic_t refcount (void) const; - - /// If @a symbol_name is in the symbol table of the DLL a pointer to - /// the @a symbol_name is returned. Otherwise, returns 0. Set the - /// ignore_errors flag to supress logging errors if symbol_name isn't - /// found. This is nice if you just want to probe a dll to see what's - /// available, since missing functions in that case aren't really errors. - void *symbol (const ACE_TCHAR *symbol_name, int ignore_errors = 0); - - /** - * Return the handle to the caller. If @a become_owner is non-0 then - * caller assumes ownership of the handle so we decrement the retcount. - */ - ACE_SHLIB_HANDLE get_handle (int become_owner = 0); - -private: - - /// Returns a pointer to a string explaining why <symbol> or <open> - /// failed. This is used internal to print out the error to the log, - /// but since this object is shared, we can't store or return the error - /// to the caller. - auto_ptr <ACE_TString> error (void); - - // Builds array of DLL names to try to dlopen, based on platform - // and configured DLL prefixes/suffixes. - // Returns the array of names to try in try_names. - void get_dll_names (const ACE_TCHAR *dll_name, - ACE_Array<ACE_TString> &try_names); - - // Disallow copying and assignment since we don't handle them. - ACE_DLL_Handle (const ACE_DLL_Handle &); - void operator= (const ACE_DLL_Handle &); - -private: - - // Keep track of how many ACE_DLL objects have a reference to this - // dll. - sig_atomic_t refcount_; - - /// Name of the shared library. - ACE_TCHAR *dll_name_; - - /// Handle to the actual library loaded by the OS. - ACE_SHLIB_HANDLE handle_; - - /// Keeps track of whether or not open() has ever been called. This - /// helps get around problem on Linux, and perhaps other OS's, that - /// seg-fault if dlerror() is called before the ld library has been - /// initialized by a call to dlopen(). - static sig_atomic_t open_called_; - -#if defined (ACE_MT_SAFE) && (ACE_MT_SAFE != 0) - /// Synchronization variable for the MT_SAFE Repository - ACE_Thread_Mutex lock_; -#endif /* ACE_MT_SAFE */ -}; - -class ACE_Framework_Repository; - -/** - * @class ACE_DLL_Manager - * - * @brief This class is a singleton and serves as a factory and - * repository for instances of ACE_DLL_Handle. - * - * This class is a singleton whose lifetime is managed by the - * ACE_Framework_Repository. Although it is normally meant to be - * used directly only by ACE_DLL, applications can call the unload_policy() - * methods in order get/set the the dll unload policy. Unload policies include - * per_process/per-dll and eager/lazy. Dlls can export set their own policy - * by using the ACE_DLL_UNLOAD_POLICY macro found in config-all.h. If a dll - * choses to set an unload policy, it will be used when the per-dll policy - * (the default) is in effect. If the per-dll policy is in effect and a dll - * has not chosen to set a policy, the current per-process policy will be - * used. - * - * The following policy macros are provided in config-all.h: - * - * ACE_DLL_UNLOAD_POLICY_PER_PROCESS - Per-process policy that unloads dlls - * eagerly. - * - * ACE_DLL_UNLOAD_POLICY_PER_DLL - Apply policy on a per-dll basis. If the - * dll doesn't use one of the macros below, the current per-process policy - * will be used. - * - * ACE_DLL_UNLOAD_POLICY_LAZY - Don't unload dll when refcount reaches - * zero, i.e., wait for either an explicit unload request or program exit. - * - * ACE_DLL_UNLOAD_POLICY_DEFAULT - Default policy allows dlls to control - * their own destinies, but will unload those that don't make a choice eagerly. - * - */ -class ACE_Export ACE_DLL_Manager -{ -public: - friend class ACE_Framework_Repository; - - enum - { - DEFAULT_SIZE = ACE_DEFAULT_DLL_MANAGER_SIZE - }; - - /// Return a unique instance - static ACE_DLL_Manager *instance (int size = ACE_DLL_Manager::DEFAULT_SIZE); - - /// Factory for ACE_DLL_Handle objects. If one already exits, - /// its refcount is incremented. - ACE_DLL_Handle *open_dll (const ACE_TCHAR *dll_name, - int openmode, - ACE_SHLIB_HANDLE handle); - - /// Close the underlying dll. Decrements the refcount. - int close_dll (const ACE_TCHAR *dll_name); - - /// Returns the current per-process UNLOAD_POLICY. - u_long unload_policy (void) const; - - /// Set the per-process UNLOAD_POLICY. If the policy is changed from - /// LAZY to EAGER, then it will also unload any dlls with zero - /// refcounts. - void unload_policy (u_long unload_policy); - -protected: - - /// Default constructor. - ACE_DLL_Manager (int size = ACE_DLL_Manager::DEFAULT_SIZE); - - /// Destructor. - ~ACE_DLL_Manager (void); - - // Allocate handle_vector_. - int open (int size); - - // Close all open dlls and deallocate memory. - int close (void); - - // Find dll in handle_vector_. - ACE_DLL_Handle *find_dll (const ACE_TCHAR *dll_name) const; - - // Applies strategy for unloading dll. - int unload_dll (ACE_DLL_Handle *dll_handle, int force_unload = 0); - -private: - - /// Close the singleton instance. - static void close_singleton (void); - - // Disallow copying and assignment since we don't handle these. - ACE_DLL_Manager (const ACE_DLL_Manager &); - void operator= (const ACE_DLL_Manager &); - -private: - - /// Vector containing all loaded handle objects. - ACE_DLL_Handle **handle_vector_; - - /// Current number of handles. - int current_size_; - - /// Maximum number of handles. - int total_size_; - - /// Unload strategy. - u_long unload_policy_; - - /// Pointer to a process-wide <ACE_DLL_Manager>. - static ACE_DLL_Manager *instance_; - -#if defined (ACE_MT_SAFE) && (ACE_MT_SAFE != 0) - /// Synchronization variable for the MT_SAFE Repository - ACE_Thread_Mutex lock_; -#endif /* ACE_MT_SAFE */ - -}; - -ACE_END_VERSIONED_NAMESPACE_DECL - -#include /**/ "ace/post.h" -#endif /* ACE_DLL_MANAGER_H */ |