RetroZilla/xpcom/components/xcDll.cpp

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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/* nsDll
*
* Abstraction of a Dll. Stores modifiedTime and size for easy detection of
* change in dll.
*
* dp Suresh <dp@netscape.com>
*/
#include "xcDll.h"
#include "nsDebug.h"
#include "nsIComponentManager.h"
#include "nsIComponentLoaderManager.h"
#include "nsIModule.h"
#include "nsILocalFile.h"
#include "nsDirectoryServiceDefs.h"
#include "nsDirectoryServiceUtils.h"
#include "nsCOMPtr.h"
#include "nsCRT.h"
#include "nsString.h"
#include "nsITimelineService.h"
#include "nsModule.h"
#ifdef DEBUG
#if defined(VMS)
#include <lib$routines.h>
#include <ssdef.h>
#elif defined(XP_MACOSX)
#include <signal.h>
#endif
#endif /* defined(DEBUG) */
#include "nsTraceRefcntImpl.h"
#define UNLOAD_DEPENDENT_LIBS
#ifdef HPUX
#undef UNLOAD_DEPENDENT_LIBS
#endif
#include "nsNativeComponentLoader.h"
nsDll::nsDll(nsIFile *dllSpec, nsNativeComponentLoader *loader)
: m_dllSpec(do_QueryInterface(dllSpec)),
m_instance(NULL),
m_moduleObject(NULL),
m_loader(loader),
m_markForUnload(PR_FALSE)
{
NS_ASSERTION(loader, "Null loader when creating a nsDLL");
}
nsDll::~nsDll(void)
{
//#if DEBUG_dougt
// The dll gets deleted when the dllStore is destroyed. This happens on
// app shutdown. At that point, unloading dlls can cause crashes if we have
// - dll dependencies
// - callbacks
// - static dtors
// Hence turn it back on after all the above have been removed.
//Unload();
//#endif
}
void
nsDll::GetDisplayPath(nsACString& aLeafName)
{
m_dllSpec->GetNativeLeafName(aLeafName);
if (aLeafName.IsEmpty())
aLeafName.AssignLiteral("unknown!");
}
PRBool
nsDll::HasChanged()
{
nsCOMPtr<nsIComponentLoaderManager> manager = do_QueryInterface(m_loader->mCompMgr);
if (!manager)
return PR_TRUE;
// If mod date has changed, then dll has changed
PRInt64 currentDate;
nsresult rv = m_dllSpec->GetLastModifiedTime(&currentDate);
if (NS_FAILED(rv))
return PR_TRUE;
PRBool changed = PR_TRUE;
manager->HasFileChanged(m_dllSpec, nsnull, currentDate, &changed);
return changed;
}
PRBool nsDll::Load(void)
{
if (m_instance != NULL)
{
// Already loaded
return (PR_TRUE);
}
if (m_dllSpec)
{
#ifdef NS_BUILD_REFCNT_LOGGING
nsTraceRefcntImpl::SetActivityIsLegal(PR_FALSE);
#endif
// load the component
nsCOMPtr<nsILocalFile> lf(do_QueryInterface(m_dllSpec));
NS_ASSERTION(lf, "nsIFile here must implement a nsILocalFile");
lf->Load(&m_instance);
#ifdef NS_BUILD_REFCNT_LOGGING
nsTraceRefcntImpl::SetActivityIsLegal(PR_TRUE);
if (m_instance) {
// Inform refcnt tracer of new library so that calls through the
// new library can be traced.
nsXPIDLCString displayPath;
GetDisplayPath(displayPath);
nsTraceRefcntImpl::LoadLibrarySymbols(displayPath.get(), m_instance);
}
#endif
}
#ifdef SHOULD_IMPLEMENT_BREAKAFTERLOAD
// Debugging help for components. Component dlls need to have their
// symbols loaded before we can put a breakpoint in the debugger.
// This will help figureing out the point when the dll was loaded.
nsXPIDLCString displayPath;
GetDisplayPath(displayPath);
BreakAfterLoad(displayPath.get());
#endif
return ((m_instance == NULL) ? PR_FALSE : PR_TRUE);
}
PRBool nsDll::Unload(void)
{
if (m_instance == NULL)
return (PR_FALSE);
// Shutdown the dll
Shutdown();
#ifdef NS_BUILD_REFCNT_LOGGING
nsTraceRefcntImpl::SetActivityIsLegal(PR_FALSE);
#endif
PRStatus ret = PR_UnloadLibrary(m_instance);
#ifdef NS_BUILD_REFCNT_LOGGING
nsTraceRefcntImpl::SetActivityIsLegal(PR_TRUE);
#endif
if (ret == PR_SUCCESS)
{
m_instance = NULL;
return (PR_TRUE);
}
else
return (PR_FALSE);
}
void * nsDll::FindSymbol(const char *symbol)
{
if (symbol == NULL)
return (NULL);
// If not already loaded, load it now.
if (Load() != PR_TRUE)
return (NULL);
return(PR_FindSymbol(m_instance, symbol));
}
// Component dll specific functions
nsresult nsDll::GetDllSpec(nsIFile **fsobj)
{
NS_ASSERTION(m_dllSpec, "m_dllSpec NULL");
NS_ASSERTION(fsobj, "xcDll::GetModule : Null argument" );
*fsobj = m_dllSpec;
NS_ADDREF(*fsobj);
return NS_OK;
}
nsresult nsDll::GetModule(nsISupports *servMgr, nsIModule **cobj)
{
// using the backpointer of the loader.
nsIComponentManager* compMgr = m_loader->mCompMgr;
NS_ASSERTION(compMgr, "Global Component Manager is null" );
if (!compMgr) return NS_ERROR_UNEXPECTED;
NS_ASSERTION(cobj, "xcDll::GetModule : Null argument" );
if (m_moduleObject)
{
NS_ADDREF(m_moduleObject);
*cobj = m_moduleObject;
return NS_OK;
}
// If not already loaded, load it now.
if (Load() != PR_TRUE) return NS_ERROR_FAILURE;
// We need a nsIFile for location
if (!m_dllSpec)
{
return NS_ERROR_FAILURE;
}
nsGetModuleProc proc =
(nsGetModuleProc) FindSymbol(NS_GET_MODULE_SYMBOL);
if (proc == NULL)
return NS_ERROR_FACTORY_NOT_LOADED;
nsresult rv = (*proc) (compMgr, m_dllSpec, &m_moduleObject);
if (NS_SUCCEEDED(rv))
{
NS_ADDREF(m_moduleObject);
*cobj = m_moduleObject;
}
return rv;
}
// These are used by BreakAfterLoad, below.
#ifdef SHOULD_IMPLEMENT_BREAKAFTERLOAD
static nsCString *sBreakList[16];
static int sBreakListCount = 0;
#endif
nsresult nsDll::Shutdown(void)
{
// Release the module object if we got one
nsrefcnt refcnt;
if (m_moduleObject)
{
NS_RELEASE2(m_moduleObject, refcnt);
NS_ASSERTION(refcnt == 0, "Dll moduleObject refcount non zero");
}
#ifdef SHOULD_IMPLEMENT_BREAKAFTERLOAD
for (int i = 0; i < sBreakListCount; i++)
{
delete sBreakList[i];
sBreakList[i] = nsnull;
}
sBreakListCount = 0;
#endif
return NS_OK;
}
#ifdef SHOULD_IMPLEMENT_BREAKAFTERLOAD
void nsDll::BreakAfterLoad(const char *nsprPath)
{
static PRBool firstTime = PR_TRUE;
// return if invalid input
if (!nsprPath || !*nsprPath) return;
// return if nothing to break on
if (!firstTime && sBreakListCount == 0) return;
if (firstTime)
{
firstTime = PR_FALSE;
// Form the list of dlls to break on load
nsCAutoString envList(getenv("XPCOM_BREAK_ON_LOAD"));
if (envList.IsEmpty()) return;
PRInt32 ofset = 0;
PRInt32 start = 0;
do
{
ofset = envList.FindChar(':', start);
sBreakList[sBreakListCount] = new nsCString();
envList.Mid(*(sBreakList[sBreakListCount]), start, ofset);
sBreakListCount++;
start = ofset + 1;
}
while (ofset != -1 && 16 > sBreakListCount); // avoiding vc6.0 compiler issue. count < thinks it is starting a template
}
// Find the dllname part of the string
nsCString currentPath(nsprPath);
PRInt32 lastSep = currentPath.RFindCharInSet(":\\/");
for (int i=0; i<sBreakListCount; i++)
if (currentPath.Find(*(sBreakList[i]), PR_TRUE, lastSep) > 0)
{
// Loading a dll that we want to break on
// Put your breakpoint here
fprintf(stderr, "...Loading module %s\n", nsprPath);
// Break in the debugger here.
#if defined(__i386) && defined(__GNUC__)
asm("int $3");
#elif defined(VMS)
lib$signal(SS$_DEBUG);
#elif defined(XP_MACOSX)
raise(SIGTRAP);
#endif
}
return;
}
#endif /* SHOULD_IMPLEMENT_BREAKAFTERLOAD */