ACE_DLL Class Reference

Provides an abstract interface for handling various DLL operations. More...

#include <DLL.h>

Collaboration diagram for ACE_DLL:

Collaboration graph
[legend]
List of all members.

Public Member Functions

 ACE_DLL (int close_handle_on_destruction=1)
 ACE_DLL (const ACE_TCHAR *dll_name, int open_mode=ACE_DEFAULT_SHLIB_MODE, int close_handle_on_destruction=1)
 ACE_DLL (const ACE_DLL &)
 Copy constructor.
int open (const ACE_TCHAR *dll_name, int open_mode=ACE_DEFAULT_SHLIB_MODE, int close_handle_on_destruction=1)
int close (void)
 Call to close the DLL object.
 ~ACE_DLL (void)
void * symbol (const ACE_TCHAR *symbol_name, int ignore_errors=0)
ACE_TCHARerror (void) const
ACE_SHLIB_HANDLE get_handle (int become_owner=0) const
int set_handle (ACE_SHLIB_HANDLE handle, int close_handle_on_destruction=1)
 Set the handle for the DLL object. By default, the close().

Private Member Functions

int open_i (const ACE_TCHAR *dll_name, int open_mode=ACE_DEFAULT_SHLIB_MODE, int close_handle_on_destruction=1, ACE_SHLIB_HANDLE handle=0)
void operator= (const ACE_DLL &)

Private Attributes

int open_mode_
 Open mode.
ACE_TCHARdll_name_
int close_handle_on_destruction_
ACE_DLL_Handledll_handle_
int error_
 Flag to record if the last operation had an error.

Detailed Description

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. Operations open(), close(), and symbol() have been implemented to help opening/closing and extracting symbol information from a DLL, respectively.


Constructor & Destructor Documentation

ACE_DLL::ACE_DLL int  close_handle_on_destruction = 1  )  [explicit]
 

Default constructor. By default, the close() operation on the object will be invoked before it is destroyed.

ACE_DLL::ACE_DLL const ACE_TCHAR dll_name,
int  open_mode = ACE_DEFAULT_SHLIB_MODE,
int  close_handle_on_destruction = 1
[explicit]
 

This constructor opens and dynamically links 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 dll_name is first loaded and <RTLD_GLOBAL>, which makes symbols available for relocation processing of any other DLLs.

ACE_DLL::ACE_DLL const ACE_DLL  ) 
 

Copy constructor.

ACE_DLL::~ACE_DLL void   ) 
 

Called when the DLL object is destroyed -- invokes close() if the <close_handle_on_destruction> flag is set in the constructor or open() method.


Member Function Documentation

int ACE_DLL::close void   ) 
 

Call to close the DLL object.

ACE_TCHAR * ACE_DLL::error void   )  const
 

Returns a pointer to a string explaining that an error occured. You will need to consult the error log for the actual error string returned by the OS.

ACE_SHLIB_HANDLE ACE_DLL::get_handle int  become_owner = 0  )  const
 

Return the handle to the caller. If become_owner is non-0 then caller assumes ownership of the handle and the ACE_DLL object won't call close() when it goes out of scope, even if <close_handle_on_destruction> is set.

int ACE_DLL::open const ACE_TCHAR dll_name,
int  open_mode = ACE_DEFAULT_SHLIB_MODE,
int  close_handle_on_destruction = 1
 

This method opens and dynamically links 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 dll_name>is first loaded and <RTLD_GLOBAL>, which makes symbols available for relocation processing of any other DLLs.

Parameters:
dll_name The name of the dll.
open_mode How the dll is opened.
close_handle_on_destruction Close the handle when object is destroyed.
Return values:
-1 On failure
0 On success.

int ACE_DLL::open_i const ACE_TCHAR dll_name,
int  open_mode = ACE_DEFAULT_SHLIB_MODE,
int  close_handle_on_destruction = 1,
ACE_SHLIB_HANDLE  handle = 0
[private]
 

void ACE_DLL::operator= const ACE_DLL  )  [private]
 

int ACE_DLL::set_handle ACE_SHLIB_HANDLE  handle,
int  close_handle_on_destruction = 1
 

Set the handle for the DLL object. By default, the close().

void * ACE_DLL::symbol const ACE_TCHAR symbol_name,
int  ignore_errors = 0
 

If symbol_name is in the symbol table of the DLL a pointer to the symbol_name is returned. Otherwise, returns 0. Setting ignore_errors = 1 allows you to probe a dll without generating error messages in the log. Handy for determining the capabilities of a library.


Member Data Documentation

int ACE_DLL::close_handle_on_destruction_ [private]
 

This flag keeps track of whether we should close the handle automatically when the object is destroyed.

ACE_DLL_Handle* ACE_DLL::dll_handle_ [private]
 

ACE_TCHAR* ACE_DLL::dll_name_ [private]
 

Keep track of the name of the loaded dll, so it can be used to remove framework components, singletons that live in the dll, prior to unloading the dll in the close() method.

int ACE_DLL::error_ [private]
 

Flag to record if the last operation had an error.

int ACE_DLL::open_mode_ [private]
 

Open mode.


The documentation for this class was generated from the following files:
Generated on Wed Nov 23 15:48:27 2005 for ACE by  doxygen 1.4.5