/* * tclLoad.c -- * * This file provides the generic portion (those that are the same * on all platforms) of Tcl's dynamic loading facilities. * * 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: tclLoad.c,v 1.1.1.1 2007/07/10 15:04:23 duncan Exp $ */ #include "tclInt.h" /* * The following structure describes a package that has been loaded * either dynamically (with the "load" command) or statically (as * indicated by a call to TclGetLoadedPackages). All such packages * are linked together into a single list for the process. Packages * are never unloaded, until the application exits, when * TclFinalizeLoad is called, and these structures are freed. */ typedef struct LoadedPackage { char *fileName; /* Name of the file from which the * package was loaded. An empty string * means the package is loaded statically. * Malloc-ed. */ char *packageName; /* Name of package prefix for the package, * properly capitalized (first letter UC, * others LC), no "_", as in "Net". * Malloc-ed. */ Tcl_LoadHandle loadHandle; /* Token for the loaded file which should be * passed to (*unLoadProcPtr)() when the file * is no longer needed. If fileName is NULL, * then this field is irrelevant. */ Tcl_PackageInitProc *initProc; /* Initialization procedure to call to * incorporate this package into a trusted * interpreter. */ Tcl_PackageInitProc *safeInitProc; /* Initialization procedure to call to * incorporate this package into a safe * interpreter (one that will execute * untrusted scripts). NULL means the * package can't be used in unsafe * interpreters. */ Tcl_FSUnloadFileProc *unLoadProcPtr; /* Procedure to use to unload this package. * If NULL, then we do not attempt to unload * the package. If fileName is NULL, then * this field is irrelevant. */ struct LoadedPackage *nextPtr; /* Next in list of all packages loaded into * this application process. NULL means * end of list. */ } LoadedPackage; /* * TCL_THREADS * There is a global list of packages that is anchored at firstPackagePtr. * Access to this list is governed by a mutex. */ static LoadedPackage *firstPackagePtr = NULL; /* First in list of all packages loaded into * this process. */ TCL_DECLARE_MUTEX(packageMutex) /* * The following structure represents a particular package that has * been incorporated into a particular interpreter (by calling its * initialization procedure). There is a list of these structures for * each interpreter, with an AssocData value (key "load") for the * interpreter that points to the first package (if any). */ typedef struct InterpPackage { LoadedPackage *pkgPtr; /* Points to detailed information about * package. */ struct InterpPackage *nextPtr; /* Next package in this interpreter, or * NULL for end of list. */ } InterpPackage; /* * Prototypes for procedures that are private to this file: */ static void LoadCleanupProc _ANSI_ARGS_((ClientData clientData, Tcl_Interp *interp)); /* *---------------------------------------------------------------------- * * Tcl_LoadObjCmd -- * * This procedure is invoked to process the "load" Tcl command. * See the user documentation for details on what it does. * * Results: * A standard Tcl result. * * Side effects: * See the user documentation. * *---------------------------------------------------------------------- */ int Tcl_LoadObjCmd(dummy, interp, objc, objv) ClientData dummy; /* Not used. */ Tcl_Interp *interp; /* Current interpreter. */ int objc; /* Number of arguments. */ Tcl_Obj *CONST objv[]; /* Argument objects. */ { Tcl_Interp *target; LoadedPackage *pkgPtr, *defaultPtr; Tcl_DString pkgName, tmp, initName, safeInitName; Tcl_PackageInitProc *initProc, *safeInitProc; InterpPackage *ipFirstPtr, *ipPtr; int code, namesMatch, filesMatch; char *p, *fullFileName, *packageName; Tcl_LoadHandle loadHandle; Tcl_FSUnloadFileProc *unLoadProcPtr = NULL; Tcl_UniChar ch; int offset; if ((objc < 2) || (objc > 4)) { Tcl_WrongNumArgs(interp, 1, objv, "fileName ?packageName? ?interp?"); return TCL_ERROR; } if (Tcl_FSConvertToPathType(interp, objv[1]) != TCL_OK) { return TCL_ERROR; } fullFileName = Tcl_GetString(objv[1]); Tcl_DStringInit(&pkgName); Tcl_DStringInit(&initName); Tcl_DStringInit(&safeInitName); Tcl_DStringInit(&tmp); packageName = NULL; if (objc >= 3) { packageName = Tcl_GetString(objv[2]); if (packageName[0] == '\0') { packageName = NULL; } } if ((fullFileName[0] == 0) && (packageName == NULL)) { Tcl_SetResult(interp, "must specify either file name or package name", TCL_STATIC); code = TCL_ERROR; goto done; } /* * Figure out which interpreter we're going to load the package into. */ target = interp; if (objc == 4) { char *slaveIntName; slaveIntName = Tcl_GetString(objv[3]); target = Tcl_GetSlave(interp, slaveIntName); if (target == NULL) { return TCL_ERROR; } } /* * Scan through the packages that are currently loaded to see if the * package we want is already loaded. We'll use a loaded package if * it meets any of the following conditions: * - Its name and file match the once we're looking for. * - Its file matches, and we weren't given a name. * - Its name matches, the file name was specified as empty, and there * is only no statically loaded package with the same name. */ Tcl_MutexLock(&packageMutex); defaultPtr = NULL; for (pkgPtr = firstPackagePtr; pkgPtr != NULL; pkgPtr = pkgPtr->nextPtr) { if (packageName == NULL) { namesMatch = 0; } else { Tcl_DStringSetLength(&pkgName, 0); Tcl_DStringAppend(&pkgName, packageName, -1); Tcl_DStringSetLength(&tmp, 0); Tcl_DStringAppend(&tmp, pkgPtr->packageName, -1); Tcl_UtfToLower(Tcl_DStringValue(&pkgName)); Tcl_UtfToLower(Tcl_DStringValue(&tmp)); if (strcmp(Tcl_DStringValue(&tmp), Tcl_DStringValue(&pkgName)) == 0) { namesMatch = 1; } else { namesMatch = 0; } } Tcl_DStringSetLength(&pkgName, 0); filesMatch = (strcmp(pkgPtr->fileName, fullFileName) == 0); if (filesMatch && (namesMatch || (packageName == NULL))) { break; } if (namesMatch && (fullFileName[0] == 0)) { defaultPtr = pkgPtr; } if (filesMatch && !namesMatch && (fullFileName[0] != 0)) { /* * Can't have two different packages loaded from the same * file. */ Tcl_AppendResult(interp, "file \"", fullFileName, "\" is already loaded for package \"", pkgPtr->packageName, "\"", (char *) NULL); code = TCL_ERROR; Tcl_MutexUnlock(&packageMutex); goto done; } } Tcl_MutexUnlock(&packageMutex); if (pkgPtr == NULL) { pkgPtr = defaultPtr; } /* * Scan through the list of packages already loaded in the target * interpreter. If the package we want is already loaded there, * then there's nothing for us to to. */ if (pkgPtr != NULL) { ipFirstPtr = (InterpPackage *) Tcl_GetAssocData(target, "tclLoad", (Tcl_InterpDeleteProc **) NULL); for (ipPtr = ipFirstPtr; ipPtr != NULL; ipPtr = ipPtr->nextPtr) { if (ipPtr->pkgPtr == pkgPtr) { code = TCL_OK; goto done; } } } if (pkgPtr == NULL) { /* * The desired file isn't currently loaded, so load it. It's an * error if the desired package is a static one. */ if (fullFileName[0] == 0) { Tcl_AppendResult(interp, "package \"", packageName, "\" isn't loaded statically", (char *) NULL); code = TCL_ERROR; goto done; } /* * Figure out the module name if it wasn't provided explicitly. */ if (packageName != NULL) { Tcl_DStringAppend(&pkgName, packageName, -1); } else { int retc; /* * Threading note - this call used to be protected by a mutex. */ retc = TclGuessPackageName(fullFileName, &pkgName); if (!retc) { Tcl_Obj *splitPtr; Tcl_Obj *pkgGuessPtr; int pElements; char *pkgGuess; /* * The platform-specific code couldn't figure out the * module name. Make a guess by taking the last element * of the file name, stripping off any leading "lib", * and then using all of the alphabetic and underline * characters that follow that. */ splitPtr = Tcl_FSSplitPath(objv[1], &pElements); Tcl_ListObjIndex(NULL, splitPtr, pElements -1, &pkgGuessPtr); pkgGuess = Tcl_GetString(pkgGuessPtr); if ((pkgGuess[0] == 'l') && (pkgGuess[1] == 'i') && (pkgGuess[2] == 'b')) { pkgGuess += 3; } for (p = pkgGuess; *p != 0; p += offset) { offset = Tcl_UtfToUniChar(p, &ch); if ((ch > 0x100) || !(isalpha(UCHAR(ch)) /* INTL: ISO only */ || (UCHAR(ch) == '_'))) { break; } } if (p == pkgGuess) { Tcl_DecrRefCount(splitPtr); Tcl_AppendResult(interp, "couldn't figure out package name for ", fullFileName, (char *) NULL); code = TCL_ERROR; goto done; } Tcl_DStringAppend(&pkgName, pkgGuess, (p - pkgGuess)); Tcl_DecrRefCount(splitPtr); } } /* * Fix the capitalization in the package name so that the first * character is in caps (or title case) but the others are all * lower-case. */ Tcl_DStringSetLength(&pkgName, Tcl_UtfToTitle(Tcl_DStringValue(&pkgName))); /* * Compute the names of the two initialization procedures, * based on the package name. */ Tcl_DStringAppend(&initName, Tcl_DStringValue(&pkgName), -1); Tcl_DStringAppend(&initName, "_Init", 5); Tcl_DStringAppend(&safeInitName, Tcl_DStringValue(&pkgName), -1); Tcl_DStringAppend(&safeInitName, "_SafeInit", 9); /* * Call platform-specific code to load the package and find the * two initialization procedures. */ Tcl_MutexLock(&packageMutex); code = Tcl_FSLoadFile(interp, objv[1], Tcl_DStringValue(&initName), Tcl_DStringValue(&safeInitName), &initProc, &safeInitProc, &loadHandle,&unLoadProcPtr); Tcl_MutexUnlock(&packageMutex); if (code != TCL_OK) { goto done; } if (initProc == NULL) { Tcl_AppendResult(interp, "couldn't find procedure ", Tcl_DStringValue(&initName), (char *) NULL); if (unLoadProcPtr != NULL) { (*unLoadProcPtr)(loadHandle); } code = TCL_ERROR; goto done; } /* * Create a new record to describe this package. */ pkgPtr = (LoadedPackage *) ckalloc(sizeof(LoadedPackage)); pkgPtr->fileName = (char *) ckalloc((unsigned) (strlen(fullFileName) + 1)); strcpy(pkgPtr->fileName, fullFileName); pkgPtr->packageName = (char *) ckalloc((unsigned) (Tcl_DStringLength(&pkgName) + 1)); strcpy(pkgPtr->packageName, Tcl_DStringValue(&pkgName)); pkgPtr->loadHandle = loadHandle; pkgPtr->unLoadProcPtr = unLoadProcPtr; pkgPtr->initProc = initProc; pkgPtr->safeInitProc = safeInitProc; Tcl_MutexLock(&packageMutex); pkgPtr->nextPtr = firstPackagePtr; firstPackagePtr = pkgPtr; Tcl_MutexUnlock(&packageMutex); } /* * Invoke the package's initialization procedure (either the * normal one or the safe one, depending on whether or not the * interpreter is safe). */ if (Tcl_IsSafe(target)) { if (pkgPtr->safeInitProc != NULL) { code = (*pkgPtr->safeInitProc)(target); } else { Tcl_AppendResult(interp, "can't use package in a safe interpreter: ", "no ", pkgPtr->packageName, "_SafeInit procedure", (char *) NULL); code = TCL_ERROR; goto done; } } else { code = (*pkgPtr->initProc)(target); } /* * Record the fact that the package has been loaded in the * target interpreter. */ if (code == TCL_OK) { /* * Refetch ipFirstPtr: loading the package may have introduced * additional static packages at the head of the linked list! */ ipFirstPtr = (InterpPackage *) Tcl_GetAssocData(target, "tclLoad", (Tcl_InterpDeleteProc **) NULL); ipPtr = (InterpPackage *) ckalloc(sizeof(InterpPackage)); ipPtr->pkgPtr = pkgPtr; ipPtr->nextPtr = ipFirstPtr; Tcl_SetAssocData(target, "tclLoad", LoadCleanupProc, (ClientData) ipPtr); } else { TclTransferResult(target, code, interp); } done: Tcl_DStringFree(&pkgName); Tcl_DStringFree(&initName); Tcl_DStringFree(&safeInitName); Tcl_DStringFree(&tmp); return code; } /* *---------------------------------------------------------------------- * * Tcl_StaticPackage -- * * This procedure is invoked to indicate that a particular * package has been linked statically with an application. * * Results: * None. * * Side effects: * Once this procedure completes, the package becomes loadable * via the "load" command with an empty file name. * *---------------------------------------------------------------------- */ void Tcl_StaticPackage(interp, pkgName, initProc, safeInitProc) Tcl_Interp *interp; /* If not NULL, it means that the * package has already been loaded * into the given interpreter by * calling the appropriate init proc. */ CONST char *pkgName; /* Name of package (must be properly * capitalized: first letter upper * case, others lower case). */ Tcl_PackageInitProc *initProc; /* Procedure to call to incorporate * this package into a trusted * interpreter. */ Tcl_PackageInitProc *safeInitProc; /* Procedure to call to incorporate * this package into a safe interpreter * (one that will execute untrusted * scripts). NULL means the package * can't be used in safe * interpreters. */ { LoadedPackage *pkgPtr; InterpPackage *ipPtr, *ipFirstPtr; /* * Check to see if someone else has already reported this package as * statically loaded in the process. */ Tcl_MutexLock(&packageMutex); for (pkgPtr = firstPackagePtr; pkgPtr != NULL; pkgPtr = pkgPtr->nextPtr) { if ((pkgPtr->initProc == initProc) && (pkgPtr->safeInitProc == safeInitProc) && (strcmp(pkgPtr->packageName, pkgName) == 0)) { break; } } Tcl_MutexUnlock(&packageMutex); /* * If the package is not yet recorded as being loaded statically, * add it to the list now. */ if ( pkgPtr == NULL ) { pkgPtr = (LoadedPackage *) ckalloc(sizeof(LoadedPackage)); pkgPtr->fileName = (char *) ckalloc((unsigned) 1); pkgPtr->fileName[0] = 0; pkgPtr->packageName = (char *) ckalloc((unsigned) (strlen(pkgName) + 1)); strcpy(pkgPtr->packageName, pkgName); pkgPtr->loadHandle = NULL; pkgPtr->initProc = initProc; pkgPtr->safeInitProc = safeInitProc; Tcl_MutexLock(&packageMutex); pkgPtr->nextPtr = firstPackagePtr; firstPackagePtr = pkgPtr; Tcl_MutexUnlock(&packageMutex); } if (interp != NULL) { /* * If we're loading the package into an interpreter, * determine whether it's already loaded. */ ipFirstPtr = (InterpPackage *) Tcl_GetAssocData(interp, "tclLoad", (Tcl_InterpDeleteProc **) NULL); for ( ipPtr = ipFirstPtr; ipPtr != NULL; ipPtr = ipPtr->nextPtr ) { if ( ipPtr->pkgPtr == pkgPtr ) { return; } } /* * Package isn't loade in the current interp yet. Mark it as * now being loaded. */ ipPtr = (InterpPackage *) ckalloc(sizeof(InterpPackage)); ipPtr->pkgPtr = pkgPtr; ipPtr->nextPtr = ipFirstPtr; Tcl_SetAssocData(interp, "tclLoad", LoadCleanupProc, (ClientData) ipPtr); } } /* *---------------------------------------------------------------------- * * TclGetLoadedPackages -- * * This procedure returns information about all of the files * that are loaded (either in a particular intepreter, or * for all interpreters). * * Results: * The return value is a standard Tcl completion code. If * successful, a list of lists is placed in the interp's result. * Each sublist corresponds to one loaded file; its first * element is the name of the file (or an empty string for * something that's statically loaded) and the second element * is the name of the package in that file. * * Side effects: * None. * *---------------------------------------------------------------------- */ int TclGetLoadedPackages(interp, targetName) Tcl_Interp *interp; /* Interpreter in which to return * information or error message. */ char *targetName; /* Name of target interpreter or NULL. * If NULL, return info about all interps; * otherwise, just return info about this * interpreter. */ { Tcl_Interp *target; LoadedPackage *pkgPtr; InterpPackage *ipPtr; char *prefix; if (targetName == NULL) { /* * Return information about all of the available packages. */ prefix = "{"; Tcl_MutexLock(&packageMutex); for (pkgPtr = firstPackagePtr; pkgPtr != NULL; pkgPtr = pkgPtr->nextPtr) { Tcl_AppendResult(interp, prefix, (char *) NULL); Tcl_AppendElement(interp, pkgPtr->fileName); Tcl_AppendElement(interp, pkgPtr->packageName); Tcl_AppendResult(interp, "}", (char *) NULL); prefix = " {"; } Tcl_MutexUnlock(&packageMutex); return TCL_OK; } /* * Return information about only the packages that are loaded in * a given interpreter. */ target = Tcl_GetSlave(interp, targetName); if (target == NULL) { return TCL_ERROR; } ipPtr = (InterpPackage *) Tcl_GetAssocData(target, "tclLoad", (Tcl_InterpDeleteProc **) NULL); prefix = "{"; for ( ; ipPtr != NULL; ipPtr = ipPtr->nextPtr) { pkgPtr = ipPtr->pkgPtr; Tcl_AppendResult(interp, prefix, (char *) NULL); Tcl_AppendElement(interp, pkgPtr->fileName); Tcl_AppendElement(interp, pkgPtr->packageName); Tcl_AppendResult(interp, "}", (char *) NULL); prefix = " {"; } return TCL_OK; } /* *---------------------------------------------------------------------- * * LoadCleanupProc -- * * This procedure is called to delete all of the InterpPackage * structures for an interpreter when the interpreter is deleted. * It gets invoked via the Tcl AssocData mechanism. * * Results: * None. * * Side effects: * Storage for all of the InterpPackage procedures for interp * get deleted. * *---------------------------------------------------------------------- */ static void LoadCleanupProc(clientData, interp) ClientData clientData; /* Pointer to first InterpPackage structure * for interp. */ Tcl_Interp *interp; /* Interpreter that is being deleted. */ { InterpPackage *ipPtr, *nextPtr; ipPtr = (InterpPackage *) clientData; while (ipPtr != NULL) { nextPtr = ipPtr->nextPtr; ckfree((char *) ipPtr); ipPtr = nextPtr; } } /* *---------------------------------------------------------------------- * * TclFinalizeLoad -- * * This procedure is invoked just before the application exits. * It frees all of the LoadedPackage structures. * * Results: * None. * * Side effects: * Memory is freed. * *---------------------------------------------------------------------- */ void TclFinalizeLoad() { LoadedPackage *pkgPtr; /* * No synchronization here because there should just be * one thread alive at this point. Logically, * packageMutex should be grabbed at this point, but * the Mutexes get finalized before the call to this routine. * The only subsystem left alive at this point is the * memory allocator. */ while (firstPackagePtr != NULL) { pkgPtr = firstPackagePtr; firstPackagePtr = pkgPtr->nextPtr; #if defined(TCL_UNLOAD_DLLS) || defined(__WIN32__) /* * Some Unix dlls are poorly behaved - registering things like * atexit calls that can't be unregistered. If you unload * such dlls, you get a core on exit because it wants to * call a function in the dll after it's been unloaded. */ if (pkgPtr->fileName[0] != '\0') { Tcl_FSUnloadFileProc *unLoadProcPtr = pkgPtr->unLoadProcPtr; if (unLoadProcPtr != NULL) { (*unLoadProcPtr)(pkgPtr->loadHandle); } } #endif ckfree(pkgPtr->fileName); ckfree(pkgPtr->packageName); ckfree((char *) pkgPtr); } }