ERR: Cast from pointer-to-data to pointer-to-function is not allowed in C++. The cast needed by cmDynamicLoader::GetSymbolAddress is now hidden in a C file.

This commit is contained in:
Brad King 2002-09-10 15:46:49 -04:00
parent de48dbbf7c
commit 820088cefc
4 changed files with 142 additions and 43 deletions

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@ -10,6 +10,7 @@ cmSourceFile.cxx
cmSystemTools.cxx
cmDirectory.cxx
cmDynamicLoader.cxx
cmDynamicLoaderC.c
cmCommands.cxx
cmTarget.cxx
cmCustomCommand.cxx

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@ -16,7 +16,20 @@
=========================================================================*/
#include "cmDynamicLoader.h"
// This file is actually 3 different implementations.
extern "C"
{
cmDynamicLoaderFunction cmDynamicLoaderGetSymbolAddress(cmLibHandle,
const char*);
}
// Dispatch to C implementation.
cmDynamicLoaderFunction cmDynamicLoader::GetSymbolAddress(cmLibHandle lib,
const char* sym)
{
return cmDynamicLoaderGetSymbolAddress(lib, sym);
}
// This file is actually 4 different implementations.
// 1. HP machines which uses shl_load
// 2. Apple OSX which uses NSLinkModule
// 3. Windows which uses LoadLibrary
@ -40,15 +53,6 @@ int cmDynamicLoader::CloseLibrary(cmLibHandle lib)
return 0;
}
void* cmDynamicLoader::GetSymbolAddress(cmLibHandle lib, const char* sym)
{
void* addr;
int status;
status = shl_findsym (&lib, sym, TYPE_PROCEDURE, &addr);
return (status < 0) ? (void*)0 : addr;
}
const char* cmDynamicLoader::LibPrefix()
{
return "lib";
@ -88,20 +92,6 @@ int cmDynamicLoader::CloseLibrary(cmLibHandle lib)
return 0;
}
void* cmDynamicLoader::GetSymbolAddress(cmLibHandle lib, const char* sym)
{
void *result=0;
if(NSIsSymbolNameDefined(sym))
{
NSSymbol symbol= NSLookupAndBindSymbol(sym);
if(symbol)
{
result = NSAddressOfSymbol(symbol);
}
}
return result;
}
const char* cmDynamicLoader::LibPrefix()
{
return "";
@ -146,19 +136,6 @@ int cmDynamicLoader::CloseLibrary(cmLibHandle lib)
return (int)FreeLibrary(lib);
}
void* cmDynamicLoader::GetSymbolAddress(cmLibHandle lib, const char* sym)
{
#ifdef UNICODE
wchar_t *wsym = new wchar_t [mbstowcs(NULL, sym, 32000)];
mbstowcs(wsym, sym, 32000);
void *ret = GetProcAddress(lib, wsym);
delete [] wsym;
return ret;
#else
return GetProcAddress(lib, sym);
#endif
}
const char* cmDynamicLoader::LibPrefix()
{
return "";
@ -211,11 +188,6 @@ int cmDynamicLoader::CloseLibrary(cmLibHandle lib)
return (int)dlclose(lib);
}
void* cmDynamicLoader::GetSymbolAddress(cmLibHandle lib, const char* sym)
{
return dlsym(lib, sym);
}
const char* cmDynamicLoader::LibPrefix()
{
return "lib";

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@ -37,6 +37,17 @@
typedef void* cmLibHandle;
#endif
// C++ Does not allow casts from pointer-to-data types to
// pointer-to-function types. However, the return type from each
// platform's symbol lookup implementation is void*. We need to hide
// the cast from void* to a pointer-to-function type in C code. The
// implementation of cmDynamicLoader::GetSymbolAddress simply calls a
// C-based implementation in cmDynamicLoaderC.c. This
// cmDynamicLoaderFunction type is the return type of
// cmDynamicLoader::GetSymbolAddress and can be cast to any other
// pointer-to-function type safely in C++.
extern "C" { typedef void (*cmDynamicLoaderFunction)(); }
class cmDynamicLoader
{
public:
@ -53,7 +64,7 @@ public:
// Description:
// Find the address of the symbol in the given library
static void* GetSymbolAddress(cmLibHandle, const char*);
static cmDynamicLoaderFunction GetSymbolAddress(cmLibHandle, const char*);
// Description:
// Return the library prefix for the given architecture

115
Source/cmDynamicLoaderC.c Normal file
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@ -0,0 +1,115 @@
/*=========================================================================
Program: Insight Segmentation & Registration Toolkit
Module: $RCSfile$
Language: C++
Date: $Date$
Version: $Revision$
Copyright (c) 2002 Insight Consortium. All rights reserved.
See ITKCopyright.txt or http://www.itk.org/HTML/Copyright.htm for details.
This software is distributed WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the above copyright notices for more information.
=========================================================================*/
// This file is actually 4 different implementations.
// 1. HP machines which uses shl_load
// 2. Apple OSX which uses NSLinkModule
// 3. Windows which uses LoadLibrary
// 4. Most unix systems which use dlopen (default )
// Each part of the ifdef contains a complete implementation for
// the static methods of cmDynamicLoader.
// Ugly stuff for library handles
// They are different on several different OS's
#if defined(__hpux)
# include <dl.h>
typedef shl_t cmLibHandle;
#elif defined(_WIN32)
#include <windows.h>
typedef HMODULE cmLibHandle;
#else
typedef void* cmLibHandle;
#endif
typedef void (*cmDynamicLoaderFunction)();
// ---------------------------------------------------------------
// 1. Implementation for HPUX machines
#ifdef __hpux
#define CMDYNAMICLOADER_DEFINED 1
#include <dl.h>
cmDynamicLoaderFunction cmDynamicLoaderGetSymbolAddress(cmLibHandle lib,
const char* sym)
{
void* addr;
int status;
status = shl_findsym (&lib, sym, TYPE_PROCEDURE, &addr);
return (cmDynamicLoaderFunction)((status < 0) ? (void*)0 : addr);
}
#endif
// ---------------------------------------------------------------
// 2. Implementation for Darwin (including OSX) Machines
#ifdef __APPLE__
#define CMDYNAMICLOADER_DEFINED
#include <mach-o/dyld.h>
cmDynamicLoaderFunction cmDynamicLoaderGetSymbolAddress(cmLibHandle lib,
const char* sym)
{
void *result=0;
if(NSIsSymbolNameDefined(sym))
{
NSSymbol symbol= NSLookupAndBindSymbol(sym);
if(symbol)
{
result = NSAddressOfSymbol(symbol);
}
}
return (cmDynamicLoaderFunction)result;
}
#endif
// ---------------------------------------------------------------
// 3. Implementation for Windows win32 code
#ifdef _WIN32
#include <windows.h>
#define CMDYNAMICLOADER_DEFINED 1
cmDynamicLoaderFunction cmDynamicLoaderGetSymbolAddress(cmLibHandle lib,
const char* sym)
{
#ifdef UNICODE
wchar_t *wsym = new wchar_t [mbstowcs(NULL, sym, 32000)];
mbstowcs(wsym, sym, 32000);
void *ret = GetProcAddress(lib, wsym);
delete [] wsym;
return (cmDynamicLoaderFunction)ret;
#else
return (cmDynamicLoaderFunction)GetProcAddress(lib, sym);
#endif
}
#endif
// ---------------------------------------------------------------
// 4. Implementation for default UNIX machines.
// if nothing has been defined then use this
#ifndef CMDYNAMICLOADER_DEFINED
#define CMDYNAMICLOADER_DEFINED
// Setup for most unix machines
#include <dlfcn.h>
cmDynamicLoaderFunction cmDynamicLoaderGetSymbolAddress(cmLibHandle lib,
const char* sym)
{
return (cmDynamicLoaderFunction)dlsym(lib, sym);
}
#endif