/*
* tclLoadDl.c --
*
* This procedure provides a version of the TclLoadFile that
* works with the "dlopen" and "dlsym" library procedures for
* dynamic loading.
*
* Copyright (c) 1995-1997 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and redistribution
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
* RCS: @(#) $Id: tclLoadDl.c,v 1.13 2002/10/10 12:25:53 vincentdarley Exp $
*/
#include "tclInt.h"
#ifdef NO_DLFCN_H
# include "../compat/dlfcn.h"
#else
# include <dlfcn.h>
#endif
/*
* In some systems, like SunOS 4.1.3, the RTLD_NOW flag isn't defined
* and this argument to dlopen must always be 1. The RTLD_GLOBAL
* flag is needed on some systems (e.g. SCO and UnixWare) but doesn't
* exist on others; if it doesn't exist, set it to 0 so it has no effect.
*/
#ifndef RTLD_NOW
# define RTLD_NOW 1
#endif
#ifndef RTLD_GLOBAL
# define RTLD_GLOBAL 0
#endif
/*
*---------------------------------------------------------------------------
*
* 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 interp'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. */
{
VOID *handle;
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);
handle = dlopen(native, RTLD_NOW | RTLD_GLOBAL);
if (handle == NULL) {
/*
* 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);
handle = dlopen(native, RTLD_NOW | RTLD_GLOBAL);
Tcl_DStringFree(&ds);
}
if (handle == NULL) {
Tcl_AppendResult(interp, "couldn't load file \"",
Tcl_GetString(pathPtr),
"\": ", dlerror(), (char *) NULL);
return TCL_ERROR;
}
*unloadProcPtr = &TclpUnloadFile;
*loadHandle = (Tcl_LoadHandle)handle;
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;
{
CONST char *native;
Tcl_DString newName, ds;
VOID *handle = (VOID*)loadHandle;
Tcl_PackageInitProc *proc;
/*
* Some platforms still add an underscore to the beginning of symbol
* names. If we can't find a name without an underscore, try again
* with the underscore.
*/
native = Tcl_UtfToExternalDString(NULL, symbol, -1, &ds);
proc = (Tcl_PackageInitProc *) dlsym(handle, /* INTL: Native. */
native);
if (proc == NULL) {
Tcl_DStringInit(&newName);
Tcl_DStringAppend(&newName, "_", 1);
native = Tcl_DStringAppend(&newName, native, -1);
proc = (Tcl_PackageInitProc *) dlsym(handle, /* INTL: Native. */
native);
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 removed from memory.
*
*----------------------------------------------------------------------
*/
void
TclpUnloadFile(loadHandle)
Tcl_LoadHandle loadHandle; /* loadHandle returned by a previous call
* to TclpDlopen(). The loadHandle is
* a token that represents the loaded
* file. */
{
VOID *handle;
handle = (VOID *) loadHandle;
dlclose(handle);
}
/*
*----------------------------------------------------------------------
*
* 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;
}