/* * tclMain.c -- * * Main program for Tcl shells and other Tcl-based applications. * This file contains a generic main program for Tcl shells and other * Tcl-based applications. It can be used as-is for many applications, * just by supplying a different appInitProc function for each specific * application. Or, it can be used as a template for creating new main * programs for Tcl applications. * * Copyright (c) 1988-1994 The Regents of the University of California. * Copyright (c) 1994-1997 Sun Microsystems, Inc. * Copyright (c) 2000 Ajuba Solutions. * * See the file "license.terms" for information on usage and redistribution of * this file, and for a DISCLAIMER OF ALL WARRANTIES. */ /* * On Windows, this file needs to be compiled twice, once with UNICODE and * _UNICODE defined. This way both Tcl_Main and Tcl_MainExW can be * implemented, sharing the same source code. */ #include "tclInt.h" /* * The default prompt used when the user has not overridden it. */ #define DEFAULT_PRIMARY_PROMPT "% " /* * This file can be compiled on Windows in UNICODE mode, as well as on all * other platforms using the native encoding. This is done by using the normal * Windows functions like _tcscmp, but on platforms which don't have * we have to translate that to strcmp here. */ #ifndef _WIN32 # define TCHAR char # define TEXT(arg) arg # define _tcscmp strcmp #endif static inline Tcl_Obj * NewNativeObj( TCHAR *string) { Tcl_DString ds; #ifdef UNICODE Tcl_DStringInit(&ds); Tcl_WCharToUtfDString(string, -1, &ds); #else Tcl_ExternalToUtfDString(NULL, (char *) string, -1, &ds); #endif return TclDStringToObj(&ds); } /* * Declarations for various library functions and variables (don't want to * include tclPort.h here, because people might copy this file out of the Tcl * source directory to make their own modified versions). */ #if defined _MSC_VER && _MSC_VER < 1900 /* isatty is always defined on MSVC 14.0, but not necessarily as CRTIMPORT. */ extern CRTIMPORT int isatty(int fd); #endif /* * The thread-local variables for this file's functions. */ typedef struct { Tcl_Obj *path; /* The filename of the script for *_Main() * routines to [source] as a startup script, * or NULL for none set, meaning enter * interactive mode. */ Tcl_Obj *encoding; /* The encoding of the startup script file. */ Tcl_MainLoopProc *mainLoopProc; /* Any installed main loop handler. The main * extension that installs these is Tk. */ } ThreadSpecificData; /* * Structure definition for information used to keep the state of an * interactive command processor that reads lines from standard input and * writes prompts and results to standard output. */ typedef enum { PROMPT_NONE, /* Print no prompt */ PROMPT_START, /* Print prompt for command start */ PROMPT_CONTINUE /* Print prompt for command continuation */ } PromptType; typedef struct { Tcl_Channel input; /* The standard input channel from which lines * are read. */ int tty; /* Non-zero means standard input is a * terminal-like device. Zero means it's a * file. */ Tcl_Obj *commandPtr; /* Used to assemble lines of input into Tcl * commands. */ PromptType prompt; /* Next prompt to print */ Tcl_Interp *interp; /* Interpreter that evaluates interactive * commands. */ } InteractiveState; /* * Forward declarations for functions defined later in this file. */ MODULE_SCOPE Tcl_MainLoopProc *TclGetMainLoop(void); static void Prompt(Tcl_Interp *interp, InteractiveState *isPtr); static void StdinProc(ClientData clientData, int mask); static void FreeMainInterp(ClientData clientData); #if !defined(_WIN32) || defined(UNICODE) static Tcl_ThreadDataKey dataKey; /* *---------------------------------------------------------------------- * * Tcl_SetStartupScript -- * * Sets the path and encoding of the startup script to be evaluated by * Tcl_Main, used to override the command line processing. * * Results: * None. * * Side effects: * *---------------------------------------------------------------------- */ void Tcl_SetStartupScript( Tcl_Obj *path, /* Filesystem path of startup script file */ const char *encoding) /* Encoding of the data in that file */ { ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); Tcl_Obj *newEncoding = NULL; if (encoding != NULL) { newEncoding = Tcl_NewStringObj(encoding, -1); } if (tsdPtr->path != NULL) { Tcl_DecrRefCount(tsdPtr->path); } tsdPtr->path = path; if (tsdPtr->path != NULL) { Tcl_IncrRefCount(tsdPtr->path); } if (tsdPtr->encoding != NULL) { Tcl_DecrRefCount(tsdPtr->encoding); } tsdPtr->encoding = newEncoding; if (tsdPtr->encoding != NULL) { Tcl_IncrRefCount(tsdPtr->encoding); } } /* *---------------------------------------------------------------------- * * Tcl_GetStartupScript -- * * Gets the path and encoding of the startup script to be evaluated by * Tcl_Main. * * Results: * The path of the startup script; NULL if none has been set. * * Side effects: * If encodingPtr is not NULL, stores a (const char *) in it pointing to * the encoding name registered for the startup script. Tcl retains * ownership of the string, and may free it. Caller should make a copy * for long-term use. * *---------------------------------------------------------------------- */ Tcl_Obj * Tcl_GetStartupScript( const char **encodingPtr) /* When not NULL, points to storage for the * (const char *) that points to the * registered encoding name for the startup * script. */ { ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); if (encodingPtr != NULL) { if (tsdPtr->encoding == NULL) { *encodingPtr = NULL; } else { *encodingPtr = Tcl_GetString(tsdPtr->encoding); } } return tsdPtr->path; } /*---------------------------------------------------------------------- * * Tcl_SourceRCFile -- * * This function is typically invoked by Tcl_Main of Tk_Main function to * source an application specific rc file into the interpreter at startup * time. * * Results: * None. * * Side effects: * Depends on what's in the rc script. * *---------------------------------------------------------------------- */ void Tcl_SourceRCFile( Tcl_Interp *interp) /* Interpreter to source rc file into. */ { Tcl_DString temp; const char *fileName; Tcl_Channel chan; fileName = Tcl_GetVar2(interp, "tcl_rcFileName", NULL, TCL_GLOBAL_ONLY); if (fileName != NULL) { Tcl_Channel c; const char *fullName; Tcl_DStringInit(&temp); fullName = Tcl_TranslateFileName(interp, fileName, &temp); if (fullName == NULL) { /* * Couldn't translate the file name (e.g. it referred to a bogus * user or there was no HOME environment variable). Just do * nothing. */ } else { /* * Test for the existence of the rc file before trying to read it. */ c = Tcl_OpenFileChannel(NULL, fullName, "r", 0); if (c != NULL) { Tcl_Close(NULL, c); if (Tcl_EvalFile(interp, fullName) != TCL_OK) { chan = Tcl_GetStdChannel(TCL_STDERR); if (chan) { Tcl_WriteObj(chan, Tcl_GetObjResult(interp)); Tcl_WriteChars(chan, "\n", 1); } } } } Tcl_DStringFree(&temp); } } #endif /* !UNICODE */ /*---------------------------------------------------------------------- * * Tcl_MainEx -- * * Main program for tclsh and most other Tcl-based applications. * * Results: * None. This function never returns (it exits the process when it's * done). * * Side effects: * This function initializes the Tcl world and then starts interpreting * commands; almost anything could happen, depending on the script being * interpreted. * *---------------------------------------------------------------------- */ void Tcl_MainEx( int argc, /* Number of arguments. */ TCHAR **argv, /* Array of argument strings. */ Tcl_AppInitProc *appInitProc, /* Application-specific initialization * function to call after most initialization * but before starting to execute commands. */ Tcl_Interp *interp) { Tcl_Obj *path, *resultPtr, *argvPtr, *appName; const char *encodingName = NULL; int code, exitCode = 0; Tcl_MainLoopProc *mainLoopProc; Tcl_Channel chan; InteractiveState is; TclpSetInitialEncodings(); TclpFindExecutable((const char *)argv[0]); Tcl_InitMemory(interp); is.interp = interp; is.prompt = PROMPT_START; is.commandPtr = Tcl_NewObj(); /* * If the application has not already set a startup script, parse the * first few command line arguments to determine the script path and * encoding. */ if (NULL == Tcl_GetStartupScript(NULL)) { /* * Check whether first 3 args (argv[1] - argv[3]) look like * -encoding ENCODING FILENAME * or like * FILENAME */ if ((argc > 3) && (0 == _tcscmp(TEXT("-encoding"), argv[1])) && ('-' != argv[3][0])) { Tcl_Obj *value = NewNativeObj(argv[2]); Tcl_SetStartupScript(NewNativeObj(argv[3]), Tcl_GetString(value)); Tcl_DecrRefCount(value); argc -= 3; argv += 3; } else if ((argc > 1) && ('-' != argv[1][0])) { Tcl_SetStartupScript(NewNativeObj(argv[1]), NULL); argc--; argv++; } } path = Tcl_GetStartupScript(&encodingName); if (path == NULL) { appName = NewNativeObj(argv[0]); } else { appName = path; } Tcl_SetVar2Ex(interp, "argv0", NULL, appName, TCL_GLOBAL_ONLY); argc--; argv++; Tcl_SetVar2Ex(interp, "argc", NULL, Tcl_NewIntObj(argc), TCL_GLOBAL_ONLY); argvPtr = Tcl_NewListObj(0, NULL); while (argc--) { Tcl_ListObjAppendElement(NULL, argvPtr, NewNativeObj(*argv++)); } Tcl_SetVar2Ex(interp, "argv", NULL, argvPtr, TCL_GLOBAL_ONLY); /* * Set the "tcl_interactive" variable. */ is.tty = isatty(0); Tcl_SetVar2Ex(interp, "tcl_interactive", NULL, Tcl_NewIntObj(!path && is.tty), TCL_GLOBAL_ONLY); /* * Invoke application-specific initialization. */ Tcl_Preserve(interp); if (appInitProc(interp) != TCL_OK) { chan = Tcl_GetStdChannel(TCL_STDERR); if (chan) { Tcl_WriteChars(chan, "application-specific initialization failed: ", -1); Tcl_WriteObj(chan, Tcl_GetObjResult(interp)); Tcl_WriteChars(chan, "\n", 1); } } if (Tcl_InterpDeleted(interp)) { goto done; } if (Tcl_LimitExceeded(interp)) { goto done; } if (TclFullFinalizationRequested()) { /* * Arrange for final deletion of the main interp */ /* ARGH Munchhausen effect */ Tcl_CreateExitHandler(FreeMainInterp, interp); } /* * Invoke the script specified on the command line, if any. Must fetch it * again, as the appInitProc might have reset it. */ path = Tcl_GetStartupScript(&encodingName); if (path != NULL) { Tcl_ResetResult(interp); code = Tcl_FSEvalFileEx(interp, path, encodingName); if (code != TCL_OK) { chan = Tcl_GetStdChannel(TCL_STDERR); if (chan) { Tcl_Obj *options = Tcl_GetReturnOptions(interp, code); Tcl_Obj *keyPtr, *valuePtr; TclNewLiteralStringObj(keyPtr, "-errorinfo"); Tcl_IncrRefCount(keyPtr); Tcl_DictObjGet(NULL, options, keyPtr, &valuePtr); Tcl_DecrRefCount(keyPtr); if (valuePtr) { Tcl_WriteObj(chan, valuePtr); } Tcl_WriteChars(chan, "\n", 1); Tcl_DecrRefCount(options); } exitCode = 1; } goto done; } /* * We're running interactively. Source a user-specific startup file if the * application specified one and if the file exists. */ Tcl_SourceRCFile(interp); if (Tcl_LimitExceeded(interp)) { goto done; } /* * Process commands from stdin until there's an end-of-file. Note that we * need to fetch the standard channels again after every eval, since they * may have been changed. */ Tcl_IncrRefCount(is.commandPtr); /* * Get a new value for tty if anyone writes to ::tcl_interactive */ Tcl_LinkVar(interp, "tcl_interactive", (char *) &is.tty, TCL_LINK_BOOLEAN); is.input = Tcl_GetStdChannel(TCL_STDIN); while ((is.input != NULL) && !Tcl_InterpDeleted(interp)) { mainLoopProc = TclGetMainLoop(); if (mainLoopProc == NULL) { int length; if (is.tty) { Prompt(interp, &is); if (Tcl_InterpDeleted(interp)) { break; } if (Tcl_LimitExceeded(interp)) { break; } is.input = Tcl_GetStdChannel(TCL_STDIN); if (is.input == NULL) { break; } } if (Tcl_IsShared(is.commandPtr)) { Tcl_DecrRefCount(is.commandPtr); is.commandPtr = Tcl_DuplicateObj(is.commandPtr); Tcl_IncrRefCount(is.commandPtr); } length = Tcl_GetsObj(is.input, is.commandPtr); if (length < 0) { if (Tcl_InputBlocked(is.input)) { /* * This can only happen if stdin has been set to * non-blocking. In that case cycle back and try again. * This sets up a tight polling loop (since we have no * event loop running). If this causes bad CPU hogging, we * might try toggling the blocking on stdin instead. */ continue; } /* * Either EOF, or an error on stdin; we're done */ break; } /* * Add the newline removed by Tcl_GetsObj back to the string. Have * to add it back before testing completeness, because it can make * a difference. [Bug 1775878] */ if (Tcl_IsShared(is.commandPtr)) { Tcl_DecrRefCount(is.commandPtr); is.commandPtr = Tcl_DuplicateObj(is.commandPtr); Tcl_IncrRefCount(is.commandPtr); } Tcl_AppendToObj(is.commandPtr, "\n", 1); if (!TclObjCommandComplete(is.commandPtr)) { is.prompt = PROMPT_CONTINUE; continue; } is.prompt = PROMPT_START; /* * The final newline is syntactically redundant, and causes some * error messages troubles deeper in, so lop it back off. */ TclGetStringFromObj(is.commandPtr, &length); Tcl_SetObjLength(is.commandPtr, --length); code = Tcl_RecordAndEvalObj(interp, is.commandPtr, TCL_EVAL_GLOBAL); is.input = Tcl_GetStdChannel(TCL_STDIN); Tcl_DecrRefCount(is.commandPtr); is.commandPtr = Tcl_NewObj(); Tcl_IncrRefCount(is.commandPtr); if (code != TCL_OK) { chan = Tcl_GetStdChannel(TCL_STDERR); if (chan) { Tcl_WriteObj(chan, Tcl_GetObjResult(interp)); Tcl_WriteChars(chan, "\n", 1); } } else if (is.tty) { resultPtr = Tcl_GetObjResult(interp); Tcl_IncrRefCount(resultPtr); TclGetStringFromObj(resultPtr, &length); chan = Tcl_GetStdChannel(TCL_STDOUT); if ((length > 0) && chan) { Tcl_WriteObj(chan, resultPtr); Tcl_WriteChars(chan, "\n", 1); } Tcl_DecrRefCount(resultPtr); } } else { /* (mainLoopProc != NULL) */ /* * If a main loop has been defined while running interactively, we * want to start a fileevent based prompt by establishing a * channel handler for stdin. */ if (is.input) { if (is.tty) { Prompt(interp, &is); } Tcl_CreateChannelHandler(is.input, TCL_READABLE, StdinProc, &is); } mainLoopProc(); Tcl_SetMainLoop(NULL); if (is.input) { Tcl_DeleteChannelHandler(is.input, StdinProc, &is); } is.input = Tcl_GetStdChannel(TCL_STDIN); } /* * This code here only for the (unsupported and deprecated) [checkmem] * command. */ #ifdef TCL_MEM_DEBUG if (tclMemDumpFileName != NULL) { Tcl_SetMainLoop(NULL); Tcl_DeleteInterp(interp); } #endif /* TCL_MEM_DEBUG */ } done: mainLoopProc = TclGetMainLoop(); if ((exitCode == 0) && mainLoopProc && !Tcl_LimitExceeded(interp)) { /* * If everything has gone OK so far, call the main loop proc, if it * exists. Packages (like Tk) can set it to start processing events at * this point. */ mainLoopProc(); Tcl_SetMainLoop(NULL); } if (is.commandPtr != NULL) { Tcl_DecrRefCount(is.commandPtr); } /* * Rather than calling exit, invoke the "exit" command so that users can * replace "exit" with some other command to do additional cleanup on * exit. The Tcl_EvalObjEx call should never return. */ if (!Tcl_InterpDeleted(interp) && !Tcl_LimitExceeded(interp)) { Tcl_Obj *cmd = Tcl_ObjPrintf("exit %d", exitCode); Tcl_IncrRefCount(cmd); Tcl_EvalObjEx(interp, cmd, TCL_EVAL_GLOBAL); Tcl_DecrRefCount(cmd); } /* * If Tcl_EvalObjEx returns, trying to eval [exit], something unusual is * happening. Maybe interp has been deleted; maybe [exit] was redefined, * maybe we've blown up because of an exceeded limit. We still want to * cleanup and exit. */ Tcl_Exit(exitCode); } #if !defined(_WIN32) || defined(UNICODE) /* *--------------------------------------------------------------- * * Tcl_SetMainLoop -- * * Sets an alternative main loop function. * * Results: * None. * * Side effects: * This function will be called before Tcl exits, allowing for the * creation of an event loop. * *--------------------------------------------------------------- */ void Tcl_SetMainLoop( Tcl_MainLoopProc *proc) { ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); tsdPtr->mainLoopProc = proc; } /* *--------------------------------------------------------------- * * TclGetMainLoop -- * * Returns the current alternative main loop function. * * Results: * Returns the previously defined main loop function, or NULL to indicate * that no such function has been installed and standard tclsh behaviour * (i.e., exit once the script is evaluated if not interactive) is * requested.. * * Side effects: * None (other than possible creation of this file's TSD block). * *--------------------------------------------------------------- */ Tcl_MainLoopProc * TclGetMainLoop(void) { ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); return tsdPtr->mainLoopProc; } /* *---------------------------------------------------------------------- * * TclFullFinalizationRequested -- * * This function returns true when either -DPURIFY is specified, or the * environment variable TCL_FINALIZE_ON_EXIT is set and not "0". This * predicate is called at places affecting the exit sequence, so that the * default behavior is a fast and deadlock-free exit, and the modified * behavior is a more thorough finalization for debugging purposes (leak * hunting etc). * * Results: * A boolean. * *---------------------------------------------------------------------- */ MODULE_SCOPE int TclFullFinalizationRequested(void) { #ifdef PURIFY return 1; #else const char *fin; Tcl_DString ds; int finalize = 0; fin = TclGetEnv("TCL_FINALIZE_ON_EXIT", &ds); finalize = ((fin != NULL) && strcmp(fin, "0")); if (fin != NULL) { Tcl_DStringFree(&ds); } return finalize; #endif /* PURIFY */ } #endif /* UNICODE */ /* *---------------------------------------------------------------------- * * StdinProc -- * * This function is invoked by the event dispatcher whenever standard * input becomes readable. It grabs the next line of input characters, * adds them to a command being assembled, and executes the command if * it's complete. * * Results: * None. * * Side effects: * Could be almost arbitrary, depending on the command that's typed. * *---------------------------------------------------------------------- */ /* ARGSUSED */ static void StdinProc( ClientData clientData, /* The state of interactive cmd line */ int mask) /* Not used. */ { int code, length; InteractiveState *isPtr = clientData; Tcl_Channel chan = isPtr->input; Tcl_Obj *commandPtr = isPtr->commandPtr; Tcl_Interp *interp = isPtr->interp; if (Tcl_IsShared(commandPtr)) { Tcl_DecrRefCount(commandPtr); commandPtr = Tcl_DuplicateObj(commandPtr); Tcl_IncrRefCount(commandPtr); } length = Tcl_GetsObj(chan, commandPtr); if (length < 0) { if (Tcl_InputBlocked(chan)) { return; } if (isPtr->tty) { /* * Would be better to find a way to exit the mainLoop? Or perhaps * evaluate [exit]? Leaving as is for now due to compatibility * concerns. */ Tcl_Exit(0); } Tcl_DeleteChannelHandler(chan, StdinProc, isPtr); return; } if (Tcl_IsShared(commandPtr)) { Tcl_DecrRefCount(commandPtr); commandPtr = Tcl_DuplicateObj(commandPtr); Tcl_IncrRefCount(commandPtr); } Tcl_AppendToObj(commandPtr, "\n", 1); if (!TclObjCommandComplete(commandPtr)) { isPtr->prompt = PROMPT_CONTINUE; goto prompt; } isPtr->prompt = PROMPT_START; TclGetStringFromObj(commandPtr, &length); Tcl_SetObjLength(commandPtr, --length); /* * Disable the stdin channel handler while evaluating the command; * otherwise if the command re-enters the event loop we might process * commands from stdin before the current command is finished. Among other * things, this will trash the text of the command being evaluated. */ Tcl_CreateChannelHandler(chan, 0, StdinProc, isPtr); code = Tcl_RecordAndEvalObj(interp, commandPtr, TCL_EVAL_GLOBAL); isPtr->input = chan = Tcl_GetStdChannel(TCL_STDIN); Tcl_DecrRefCount(commandPtr); isPtr->commandPtr = commandPtr = Tcl_NewObj(); Tcl_IncrRefCount(commandPtr); if (chan != NULL) { Tcl_CreateChannelHandler(chan, TCL_READABLE, StdinProc, isPtr); } if (code != TCL_OK) { chan = Tcl_GetStdChannel(TCL_STDERR); if (chan != NULL) { Tcl_WriteObj(chan, Tcl_GetObjResult(interp)); Tcl_WriteChars(chan, "\n", 1); } } else if (isPtr->tty) { Tcl_Obj *resultPtr = Tcl_GetObjResult(interp); chan = Tcl_GetStdChannel(TCL_STDOUT); Tcl_IncrRefCount(resultPtr); TclGetStringFromObj(resultPtr, &length); if ((length > 0) && (chan != NULL)) { Tcl_WriteObj(chan, resultPtr); Tcl_WriteChars(chan, "\n", 1); } Tcl_DecrRefCount(resultPtr); } /* * If a tty stdin is still around, output a prompt. */ prompt: if (isPtr->tty && (isPtr->input != NULL)) { Prompt(interp, isPtr); isPtr->input = Tcl_GetStdChannel(TCL_STDIN); } } /* *---------------------------------------------------------------------- * * Prompt -- * * Issue a prompt on standard output, or invoke a script to issue the * prompt. * * Results: * None. * * Side effects: * A prompt gets output, and a Tcl script may be evaluated in interp. * *---------------------------------------------------------------------- */ static void Prompt( Tcl_Interp *interp, /* Interpreter to use for prompting. */ InteractiveState *isPtr) /* InteractiveState. Filled with PROMPT_NONE * after a prompt is printed. */ { Tcl_Obj *promptCmdPtr; int code; Tcl_Channel chan; if (isPtr->prompt == PROMPT_NONE) { return; } promptCmdPtr = Tcl_GetVar2Ex(interp, (isPtr->prompt==PROMPT_CONTINUE ? "tcl_prompt2" : "tcl_prompt1"), NULL, TCL_GLOBAL_ONLY); if (Tcl_InterpDeleted(interp)) { return; } if (promptCmdPtr == NULL) { defaultPrompt: if (isPtr->prompt == PROMPT_START) { chan = Tcl_GetStdChannel(TCL_STDOUT); if (chan != NULL) { Tcl_WriteChars(chan, DEFAULT_PRIMARY_PROMPT, strlen(DEFAULT_PRIMARY_PROMPT)); } } } else { code = Tcl_EvalObjEx(interp, promptCmdPtr, TCL_EVAL_GLOBAL); if (code != TCL_OK) { Tcl_AddErrorInfo(interp, "\n (script that generates prompt)"); chan = Tcl_GetStdChannel(TCL_STDERR); if (chan != NULL) { Tcl_WriteObj(chan, Tcl_GetObjResult(interp)); Tcl_WriteChars(chan, "\n", 1); } goto defaultPrompt; } } chan = Tcl_GetStdChannel(TCL_STDOUT); if (chan != NULL) { Tcl_Flush(chan); } isPtr->prompt = PROMPT_NONE; } /* *---------------------------------------------------------------------- * * FreeMainInterp -- * * Exit handler used to cleanup the main interpreter and ancillary * startup script storage at exit. * *---------------------------------------------------------------------- */ static void FreeMainInterp( ClientData clientData) { Tcl_Interp *interp = clientData; /*if (TclInExit()) return;*/ if (!Tcl_InterpDeleted(interp)) { Tcl_DeleteInterp(interp); } Tcl_SetStartupScript(NULL, NULL); Tcl_Release(interp); } /* * Local Variables: * mode: c * c-basic-offset: 4 * fill-column: 78 * End: */