/*
* 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 1.14 2002/10/29 00:04:08 das Exp $
*/
#include "tclInt.h"
#include "tclPort.h"
#include <mach-o/dyld.h>
typedef struct Tcl_DyldModuleHandle {
struct Tcl_DyldModuleHandle *nextModuleHandle;
NSModule module;
} Tcl_DyldModuleHandle;
typedef struct Tcl_DyldLoadHandle {
const struct mach_header *dyld_lib;
Tcl_DyldModuleHandle *firstModuleHandle;
} Tcl_DyldLoadHandle;
/*
*----------------------------------------------------------------------
*
* TclpDlopen --
*
* Dynamically loads a binary code file into memory and returns
* a handle to the new code.
*
* Results:
* A standard Tcl completion code. If an error occurs, an error
* message is left in the interpreter's result.
*
* Side effects:
* New code suddenly appears in memory.
*
*----------------------------------------------------------------------
*/
int
TclpDlopen(interp, pathPtr, loadHandle, unloadProcPtr)
Tcl_Interp *interp; /* Used for error reporting. */
Tcl_Obj *pathPtr; /* Name of the file containing the desired
* code (UTF-8). */
Tcl_LoadHandle *loadHandle; /* 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. */
{
Tcl_DyldLoadHandle *dyldLoadHandle;
const struct mach_header *dyld_lib;
CONST char *native;
/*
* First try the full path the user gave us. This is particularly
* important if the cwd is inside a vfs, and we are trying to load
* using a relative path.
*/
native = Tcl_FSGetNativePath(pathPtr);
dyld_lib = NSAddImage(native,
NSADDIMAGE_OPTION_WITH_SEARCHING |
NSADDIMAGE_OPTION_RETURN_ON_ERROR);
if (!dyld_lib) {
/*
* Let the OS loader examine the binary search path for
* whatever string the user gave us which hopefully refers
* to a file on the binary path
*/
Tcl_DString ds;
char *fileName = Tcl_GetString(pathPtr);
native = Tcl_UtfToExternalDString(NULL, fileName, -1, &ds);
dyld_lib = NSAddImage(native,
NSADDIMAGE_OPTION_WITH_SEARCHING |
NSADDIMAGE_OPTION_RETURN_ON_ERROR);
Tcl_DStringFree(&ds);
}
if (!dyld_lib) {
NSLinkEditErrors editError;
char *name, *msg;
NSLinkEditError(&editError, &errno, &name, &msg);
Tcl_AppendResult(interp, msg, (char *) NULL);
return TCL_ERROR;
}
dyldLoadHandle = (Tcl_DyldLoadHandle *) ckalloc(sizeof(Tcl_DyldLoadHandle));
if (!dyldLoadHandle) return TCL_ERROR;
dyldLoadHandle->dyld_lib = dyld_lib;
dyldLoadHandle->firstModuleHandle = NULL;
*loadHandle = (Tcl_LoadHandle) dyldLoadHandle;
*unloadProcPtr = &TclpUnloadFile;
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* TclpFindSymbol --
*
* Looks up a symbol, by name, through a handle associated with
* a previously loaded piece of code (shared library).
*
* Results:
* Returns a pointer to the function associated with 'symbol' if
* it is found. Otherwise returns NULL and may leave an error
* message in the interp's result.
*
*----------------------------------------------------------------------
*/
Tcl_PackageInitProc*
TclpFindSymbol(interp, loadHandle, symbol)
Tcl_Interp *interp;
Tcl_LoadHandle loadHandle;
CONST char *symbol;
{
NSSymbol nsSymbol;
CONST char *native;
Tcl_DString newName, ds;
Tcl_PackageInitProc* proc = NULL;
Tcl_DyldLoadHandle *dyldLoadHandle = (Tcl_DyldLoadHandle *) loadHandle;
/*
* dyld adds an underscore to the beginning of symbol names.
*/
native = Tcl_UtfToExternalDString(NULL, symbol, -1, &ds);
Tcl_DStringInit(&newName);
Tcl_DStringAppend(&newName, "_", 1);
native = Tcl_DStringAppend(&newName, native, -1);
nsSymbol = NSLookupSymbolInImage(dyldLoadHandle->dyld_lib, native,
NSLOOKUPSYMBOLINIMAGE_OPTION_BIND_NOW |
NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR);
if(nsSymbol) {
Tcl_DyldModuleHandle *dyldModuleHandle;
proc = NSAddressOfSymbol(nsSymbol);
dyldModuleHandle = (Tcl_DyldModuleHandle *) ckalloc(sizeof(Tcl_DyldModuleHandle));
if (dyldModuleHandle) {
dyldModuleHandle->module = NSModuleForSymbol(nsSymbol);
dyldModuleHandle->nextModuleHandle = dyldLoadHandle->firstModuleHandle;
dyldLoadHandle->firstModuleHandle = dyldModuleHandle;
}
} else {
NSLinkEditErrors editError;
char *name, *msg;
NSLinkEditError(&editError, &errno, &name, &msg);
Tcl_AppendResult(interp, msg, (char *) NULL);
}
Tcl_DStringFree(&newName);
Tcl_DStringFree(&ds);
return proc;
}
/*
*----------------------------------------------------------------------
*
* 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(loadHandle)
Tcl_LoadHandle loadHandle; /* loadHandle returned by a previous call
* to TclpDlopen(). The loadHandle is
* a token that represents the loaded
* file. */
{
Tcl_DyldLoadHandle *dyldLoadHandle = (Tcl_DyldLoadHandle *) loadHandle;
Tcl_DyldModuleHandle *dyldModuleHandle = dyldLoadHandle->firstModuleHandle;
void *ptr;
while (dyldModuleHandle) {
NSUnLinkModule(dyldModuleHandle->module, NSUNLINKMODULE_OPTION_NONE);
ptr = dyldModuleHandle;
dyldModuleHandle = dyldModuleHandle->nextModuleHandle;
ckfree(ptr);
}
ckfree(dyldLoadHandle);
}
/*
*----------------------------------------------------------------------
*
* 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;
}