summaryrefslogtreecommitdiffstats
path: root/win/tclWin32Dll.c
blob: 16c47c1520a0ffc6390be6c1f8aa9afcf4ba93f6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
/* 
 * tclWin32Dll.c --
 *
 *	This file contains the DLL entry point which sets up the 32-to-16-bit
 *	thunking code for SynchSpawn if the library is running under Win32s.
 *
 * Copyright (c) 1995-1996 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: tclWin32Dll.c,v 1.5 1999/03/10 05:52:53 stanton Exp $
 */

#include "tclWinInt.h"

typedef DWORD (WINAPI * UT32PROC)(LPVOID lpBuff, DWORD dwUserDefined,
	LPVOID *lpTranslationList);

typedef BOOL (WINAPI * PUTREGISTER)(HANDLE hModule, LPCSTR SixteenBitDLL,
	LPCSTR InitName, LPCSTR ProcName, UT32PROC* ThirtyTwoBitThunk,
	FARPROC UT32Callback, LPVOID Buff);

typedef VOID (WINAPI * PUTUNREGISTER)(HANDLE hModule);

static PUTUNREGISTER UTUnRegister = NULL;
static int           tclProcessesAttached = 0;

/*
 * The following data structure is used to keep track of all of the DLL's
 * opened by Tcl so that they can be freed with the Tcl.dll is unloaded.
 */

typedef struct LibraryList {
    HINSTANCE handle;
    struct LibraryList *nextPtr;
} LibraryList;

static LibraryList *libraryList = NULL;	/* List of currently loaded DLL's.  */

static HINSTANCE tclInstance;	/* Global library instance handle. */
static int tclPlatformId;	/* Running under NT, 95, or Win32s? */

/*
 * Declarations for functions that are only used in this file.
 */

static void 		UnloadLibraries _ANSI_ARGS_((void));

/*
 * The following declaration is for the VC++ DLL entry point.
 */

BOOL APIENTRY		DllMain _ANSI_ARGS_((HINSTANCE hInst,
			    DWORD reason, LPVOID reserved));

#ifdef __WIN32__
#ifndef STATIC_BUILD


/*
 *----------------------------------------------------------------------
 *
 * DllEntryPoint --
 *
 *	This wrapper function is used by Borland to invoke the
 *	initialization code for Tcl.  It simply calls the DllMain
 *	routine.
 *
 * Results:
 *	See DllMain.
 *
 * Side effects:
 *	See DllMain.
 *
 *----------------------------------------------------------------------
 */

BOOL APIENTRY
DllEntryPoint(hInst, reason, reserved)
    HINSTANCE hInst;		/* Library instance handle. */
    DWORD reason;		/* Reason this function is being called. */
    LPVOID reserved;		/* Not used. */
{
    return DllMain(hInst, reason, reserved);
}

/*
 *----------------------------------------------------------------------
 *
 * DllMain --
 *
 *	This routine is called by the VC++ C run time library init
 *	code, or the DllEntryPoint routine.  It is responsible for
 *	initializing various dynamically loaded libraries.
 *
 * Results:
 *	TRUE on sucess, FALSE on failure.
 *
 * Side effects:
 *	Establishes 32-to-16 bit thunk and initializes sockets library.
 *
 *----------------------------------------------------------------------
 */
BOOL APIENTRY
DllMain(hInst, reason, reserved)
    HINSTANCE hInst;		/* Library instance handle. */
    DWORD reason;		/* Reason this function is being called. */
    LPVOID reserved;		/* Not used. */
{
    switch (reason) {
    case DLL_PROCESS_ATTACH:
	if (tclProcessesAttached++) {
	    return FALSE;         /* Not the first initialization. */
	}

	TclWinInit(hInst);
	return TRUE;

    case DLL_PROCESS_DETACH:

	tclProcessesAttached--;
	if (tclProcessesAttached == 0) {
            Tcl_Finalize();
	}
	break;
    }

    return TRUE; 
}

#endif /* !STATIC_BUILD */
#endif /* __WIN32__ */

/*
 *----------------------------------------------------------------------
 *
 * TclWinInit --
 *
 *	This function initializes the internal state of the tcl library.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Initializes the 16-bit thunking library, and the tclPlatformId
 *	variable.
 *
 *----------------------------------------------------------------------
 */

void
TclWinInit(hInst)
    HINSTANCE hInst;		/* Library instance handle. */
{
    OSVERSIONINFO os;

    tclInstance = hInst;
    os.dwOSVersionInfoSize = sizeof(os);
    GetVersionEx(&os);
    tclPlatformId = os.dwPlatformId;

    /*
     * The following code stops Windows 3.x from automatically putting 
     * up Sharing Violation dialogs, e.g, when someone tries to
     * access a file that is locked or a drive with no disk in it.
     * Tcl already returns the appropriate error to the caller, and they 
     * can decide to put up their own dialog in response to that failure.  
     *
     * Under 95 and NT, the system doesn't automatically put up dialogs 
     * when the above operations fail.
     */

    if (tclPlatformId == VER_PLATFORM_WIN32s) {
	SetErrorMode(SetErrorMode(0) | SEM_FAILCRITICALERRORS);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TclpFinalize --
 *
 *	Clean up the Windows specific library state.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Unloads any DLLs and cleans up the thunking library, if
 *	necessary.
 *
 *----------------------------------------------------------------------
 */

void
TclpFinalize()
{
    /*
     * Unregister the Tcl thunk.
     */

    if (UTUnRegister != NULL) {
	UTUnRegister(tclInstance);
	UTUnRegister = NULL;
    }

    /*
     * Cleanup any dynamically loaded libraries.
     */

    UnloadLibraries();
}

/*
 *----------------------------------------------------------------------
 *
 * TclWinLoadLibrary --
 *
 *	This function is a wrapper for the system LoadLibrary.  It is
 *	responsible for adding library handles to the library list so
 *	the libraries can be freed when tcl.dll is unloaded.
 *
 * Results:
 *	Returns the handle of the newly loaded library, or NULL on
 *	failure.
 *
 * Side effects:
 *	Loads the specified library into the process.
 *
 *----------------------------------------------------------------------
 */

HINSTANCE
TclWinLoadLibrary(name)
    char *name;			/* Library file to load. */
{
    HINSTANCE handle;
    LibraryList *ptr;

    handle = LoadLibrary(name);
    if (handle != NULL) {
	ptr = (LibraryList*) ckalloc(sizeof(LibraryList));
	ptr->handle = handle;
	ptr->nextPtr = libraryList;
	libraryList = ptr;
    } else {
	TclWinConvertError(GetLastError());
    }
    return handle;
}

/*
 *----------------------------------------------------------------------
 *
 * UnloadLibraries --
 *
 *	Frees any dynamically allocated libraries loaded by Tcl.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Frees the libraries on the library list as well as the list.
 *
 *----------------------------------------------------------------------
 */

static void
UnloadLibraries()
{
    LibraryList *ptr;

    while (libraryList != NULL) {
	FreeLibrary(libraryList->handle);
	ptr = libraryList->nextPtr;
	ckfree((char*)libraryList);
	libraryList = ptr;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TclWinSynchSpawn --
 *
 *	32-bit entry point to the 16-bit SynchSpawn code.
 *
 * Results:
 *	1 on success, 0 on failure.
 *
 * Side effects:
 *	Spawns a command and waits for it to complete.
 *
 *----------------------------------------------------------------------
 */
int 
TclWinSynchSpawn(void *args, int type, void **trans, Tcl_Pid *pidPtr)
{
    static UT32PROC UTProc = NULL;
    static int utErrorCode;

    if (UTUnRegister == NULL) {
	/*
	 * Load the Universal Thunking routines from kernel32.dll.
	 */

	HINSTANCE hKernel;
	PUTREGISTER UTRegister;
	char buffer[] = "TCL16xx.DLL";

	hKernel = TclWinLoadLibrary("Kernel32.Dll");
	if (hKernel == NULL) {
	    return 0;
	}

	UTRegister = (PUTREGISTER) GetProcAddress(hKernel, "UTRegister");
	UTUnRegister = (PUTUNREGISTER) GetProcAddress(hKernel, "UTUnRegister");
	if (!UTRegister || !UTUnRegister) {
	    UnloadLibraries();
	    return 0;
	}

	/*
	 * Construct the complete name of tcl16xx.dll.
	 */

	buffer[5] = '0' + TCL_MAJOR_VERSION;
	buffer[6] = '0' + TCL_MINOR_VERSION;

	/*
	 * Register the Tcl thunk.
	 */

	if (UTRegister(tclInstance, buffer, NULL, "UTProc", &UTProc, NULL,
		NULL) == FALSE) {
	    utErrorCode = GetLastError();
	}
    }

    if (UTProc == NULL) {
	/*
	 * The 16-bit thunking DLL wasn't found.  Return error code that
	 * indicates this problem.
	 */

	SetLastError(utErrorCode);
	return 0;
    }

    UTProc(args, type, trans);
    *pidPtr = 0;
    return 1;
}

/*
 *----------------------------------------------------------------------
 *
 * TclWinGetTclInstance --
 *
 *	Retrieves the global library instance handle.
 *
 * Results:
 *	Returns the global library instance handle.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

HINSTANCE
TclWinGetTclInstance()
{
    return tclInstance;
}

/*
 *----------------------------------------------------------------------
 *
 * TclpCheckStackSpace --
 *
 *	Detect if we are about to blow the stack.  Called before an 
 *	evaluation can happen when nesting depth is checked.
 *
 * Results:
 *	1 if there is enough stack space to continue; 0 if not.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclpCheckStackSpace()
{
    /*
     * We can recurse only if there is at least TCL_WIN_STACK_THRESHOLD
     * bytes of stack space left.  alloca() is cheap on windows; basically
     * it just subtracts from the stack pointer causing the OS to throw an
     * exception if the stack pointer is set below the bottom of the stack.
     */

    try {
	alloca(TCL_WIN_STACK_THRESHOLD);
	return 1;
    } except (1) {}

    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * TclWinGetPlatformId --
 *
 *	Determines whether running under NT, 95, or Win32s, to allow 
 *	runtime conditional code.
 *
 * Results:
 *	The return value is one of:
 *	    VER_PLATFORM_WIN32s		Win32s on Windows 3.1. 
 *	    VER_PLATFORM_WIN32_WINDOWS	Win32 on Windows 95.
 *	    VER_PLATFORM_WIN32_NT	Win32 on Windows NT
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int		
TclWinGetPlatformId()
{
    return tclPlatformId;
}