/*
* tclLoadDyld.c --
*
* This procedure provides a version of the TclLoadFile that
* works with Apple's dyld dynamic loading. This file
* provided by Wilfredo Sanchez (wsanchez@apple.com).
* This works on Mac OS X.
*
* Copyright (c) 1995 Apple Computer, Inc.
*
* See the file "license.terms" for information on usage and redistribution
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
* RCS: @(#) $Id: tclLoadDyld.c,v 1.8 2002/02/25 15:21:59 das Exp $
*/
#include "tclInt.h"
#include "tclPort.h"
#include <mach-o/dyld.h>
/*
*----------------------------------------------------------------------
*
* TclpLoadFile --
*
* Dynamically loads a binary code file into memory and returns
* the addresses of two procedures within that file, if they
* are defined.
*
* Results:
* A standard Tcl completion code. If an error occurs, an error
* message is left in the interpreter's result. *proc1Ptr and *proc2Ptr
* are filled in with the addresses of the symbols given by
* *sym1 and *sym2, or NULL if those symbols can't be found.
*
* Side effects:
* New code suddenly appears in memory.
*
*----------------------------------------------------------------------
*/
int
TclpLoadFile(interp, pathPtr, sym1, sym2, proc1Ptr, proc2Ptr,
clientDataPtr, unloadProcPtr)
Tcl_Interp *interp; /* Used for error reporting. */
Tcl_Obj *pathPtr; /* Name of the file containing the desired
* code. */
CONST char *sym1, *sym2; /* Names of two procedures to look up in
* the file's symbol table. */
Tcl_PackageInitProc **proc1Ptr, **proc2Ptr;
/* Where to return the addresses corresponding
* to sym1 and sym2. */
ClientData *clientDataPtr; /* Filled with token for dynamically loaded
* file which will be passed back to
* (*unloadProcPtr)() to unload the file. */
Tcl_FSUnloadFileProc **unloadProcPtr;
/* Filled with address of Tcl_FSUnloadFileProc
* function which should be used for
* this file. */
{
NSSymbol symbol;
const struct mach_header *dyld_lib;
Tcl_DString newName, ds;
char *native;
native = Tcl_FSGetNativePath(pathPtr);
dyld_lib = NSAddImage(native,
NSADDIMAGE_OPTION_WITH_SEARCHING |
NSADDIMAGE_OPTION_RETURN_ON_ERROR);
if (!dyld_lib) {
NSLinkEditErrors editError;
char *name, *msg;
NSLinkEditError(&editError, &errno, &name, &msg);
Tcl_AppendResult(interp, msg, (char *) NULL);
return TCL_ERROR;
}
*unloadProcPtr = &TclpUnloadFile;
/*
* dyld adds an underscore to the beginning of symbol names.
*/
native = Tcl_UtfToExternalDString(NULL, sym1, -1, &ds);
Tcl_DStringInit(&newName);
Tcl_DStringAppend(&newName, "_", 1);
native = Tcl_DStringAppend(&newName, native, -1);
symbol = NSLookupSymbolInImage(dyld_lib, native,
NSLOOKUPSYMBOLINIMAGE_OPTION_BIND_NOW |
NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR);
if(symbol) {
*proc1Ptr = NSAddressOfSymbol(symbol);
*clientDataPtr = NSModuleForSymbol(symbol);
} else {
*proc1Ptr=NULL;
*clientDataPtr=NULL;
}
Tcl_DStringFree(&newName);
Tcl_DStringFree(&ds);
native = Tcl_UtfToExternalDString(NULL, sym2, -1, &ds);
Tcl_DStringInit(&newName);
Tcl_DStringAppend(&newName, "_", 1);
native = Tcl_DStringAppend(&newName, native, -1);
symbol = NSLookupSymbolInImage(dyld_lib, native,
NSLOOKUPSYMBOLINIMAGE_OPTION_BIND_NOW |
NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR);
if(symbol) {
*proc2Ptr = NSAddressOfSymbol(symbol);
} else {
*proc2Ptr=NULL;
}
Tcl_DStringFree(&newName);
Tcl_DStringFree(&ds);
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* TclpUnloadFile --
*
* Unloads a dynamically loaded binary code file from memory.
* Code pointers in the formerly loaded file are no longer valid
* after calling this function.
*
* Results:
* None.
*
* Side effects:
* Code dissapears from memory.
* Note that this is a no-op on older (OpenStep) versions of dyld.
*
*----------------------------------------------------------------------
*/
void
TclpUnloadFile(clientData)
ClientData clientData; /* ClientData returned by a previous call
* to TclpLoadFile(). The clientData is
* a token that represents the loaded
* file. */
{
NSUnLinkModule(clientData, FALSE);
}
/*
*----------------------------------------------------------------------
*
* TclGuessPackageName --
*
* If the "load" command is invoked without providing a package
* name, this procedure is invoked to try to figure it out.
*
* Results:
* Always returns 0 to indicate that we couldn't figure out a
* package name; generic code will then try to guess the package
* from the file name. A return value of 1 would have meant that
* we figured out the package name and put it in bufPtr.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
TclGuessPackageName(fileName, bufPtr)
CONST char *fileName; /* Name of file containing package (already
* translated to local form if needed). */
Tcl_DString *bufPtr; /* Initialized empty dstring. Append
* package name to this if possible. */
{
return 0;
}