summaryrefslogtreecommitdiffstats
path: root/unix/tclUnixCompat.c
blob: b0e0ae89554b56cd8ff1fafad16a15a1b5762f7b (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
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
/*
 * tclUnixCompat.c
 *
 * Written by: Zoran Vasiljevic (vasiljevic@users.sourceforge.net). 
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclUnixCompat.c,v 1.4 2006/09/07 18:53:11 vasiljevic Exp $
 *
 */

#include "tclInt.h"
#include "tclPort.h"
#include <pwd.h>
#include <grp.h>
#include <errno.h>
#include <string.h>

/*
 * Used to pad structures at size'd boundaries
 */

#define PadBuffer(buffer, length, size)         \
    if (((length) % (size))) {                  \
        (buffer) += ((length) % (size));        \
        (length) += ((length) % (size));        \
    }

/*
 * Per-thread private storage used to store values
 * returned from MT-unsafe library calls.
 */

#ifdef TCL_THREADS

typedef struct ThreadSpecificData {

    struct passwd pwd;
    char pbuf[2048];

    struct group grp;
    char gbuf[2048];

    struct hostent hent;
    char hbuf[2048];

}  ThreadSpecificData;

static Tcl_ThreadDataKey dataKey;

/*
 * Mutex to lock access to MT-unsafe calls. This is just to protect 
 * our own usage. It does not protect us from others calling the
 * same functions without (or using some different) lock. 
 */

Tcl_Mutex compatLock;

#if (!defined(HAVE_GETHOSTBYNAME_R) && !defined(HAVE_GETHOSTBYADDR_R)) || \
    (!defined(HAVE_GETPWUID_R)      && !defined(HAVE_GETGRGID_R))


/*
 *---------------------------------------------------------------------------
 *
 * CopyArray --
 *
 *      Copies array of NULL-terminated or fixed-length strings
 *      to the private buffer, honouring the size of the buffer.
 *
 * Results:
 *      Number of bytes copied on success or -1 on error (errno = ERANGE)
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

static int 
CopyArray(char **src, int elsize, char *buf, int buflen)
{
    int i, j, len = 0;
    char *p, **new;

    if (src == NULL) {
        return 0;
    }
    for (i = 0; src[i] != NULL; i++) {
        /* Empty loop to count howmany */
    }
    if ((sizeof(char *)*(i + 1)) >  buflen) {
        return -1;
    }
    len = (sizeof(char *)*(i + 1)); /* Leave place for the array */
    new = (char **)buf;
    p = buf + (sizeof(char *)*(i + 1));
    for (j = 0; j < i; j++) {
        if (elsize < 0) {
            len += strlen(src[j]) + 1;
        } else {
            len += elsize;
        }
        if (len > buflen) {
            return -1;
        }
        if (elsize < 0) {
            strcpy(p, src[j]);
        } else {
            memcpy(p, src[j], elsize);
        }
        new[j] = p;
        p = buf + len;
    }
    new[j] = NULL;

    return len;
}


/*
 *---------------------------------------------------------------------------
 *
 * CopyString --
 *
 *      Copies a NULL-terminated string to the private buffer,
 *      honouring the size of the buffer
 *
 * Results:
 *      0 success or -1 on error (errno = ERANGE)
 *
 * Side effects:
 *      None
 *
 *---------------------------------------------------------------------------
 */


static int 
CopyString(char *src, char *buf, int buflen)
{
    int len = 0;

    if (src != NULL) {
        len += strlen(src) + 1;
        if (len > buflen) {
            return -1;
        }
        strcpy(buf, src);
    }

    return len;
}
#endif /* !defined(HAVE_GETHOSTBYNAME_R) && !defined(HAVE_GETHOSTBYADDR_R) && \
    !defined(HAVE_GETPWUID_R) && !defined(HAVE_GETGRGID_R) */


#if !defined(HAVE_GETHOSTBYNAME_R) && !defined(HAVE_GETHOSTBYADDR_R)

/*
 *---------------------------------------------------------------------------
 *
 * CopyHostnent --
 *
 *      Copies string fields of the hostnent structure to the 
 *      private buffer, honouring the size of the buffer.
 *
 * Results:
 *      Number of bytes copied on success or -1 on error (errno = ERANGE)
 *
 * Side effects:
 *      None
 *
 *---------------------------------------------------------------------------
 */

static int
CopyHostent(struct hostent *tgtPtr, char *buf, int buflen)
{
    char *p = buf;
    int copied, len = 0;

    copied = CopyString(tgtPtr->h_name, p, buflen - len);
    if (copied == -1) {
    range:
        errno = ERANGE;
        return -1;
    }
    tgtPtr->h_name = (copied > 0) ? p : NULL;
    len += copied;
    p = buf + len;

    PadBuffer(p, len, sizeof(char *));
    copied = CopyArray(tgtPtr->h_aliases, -1, p, buflen - len);
    if (copied == -1) {
        goto range;
    }
    tgtPtr->h_aliases = (copied > 0) ? (char **)p : NULL;
    len += copied;
    p += len;

    PadBuffer(p, len, sizeof(char *));
    copied = CopyArray(tgtPtr->h_addr_list, tgtPtr->h_length, p, buflen - len);
    if (copied == -1) {
        goto range;
    }
    tgtPtr->h_addr_list = (copied > 0) ? (char **)p : NULL;
   
    return 0;
}
#endif /* !defined(HAVE_GETHOSTBYNAME_R) && !defined(HAVE_GETHOSTBYADDR_R) */

#if !defined(HAVE_GETPWUID_R)

/*
 *---------------------------------------------------------------------------
 *
 * CopyPwd --
 *
 *      Copies string fields of the passwd structure to the 
 *      private buffer, honouring the size of the buffer.
 *
 * Results:
 *      0 on success or -1 on error (errno = ERANGE)
 *
 * Side effects:
 *      We are not copying the gecos field as it may not be supported
 *      on all platforms.
 *
 *---------------------------------------------------------------------------
 */

static int
CopyPwd(struct passwd *tgtPtr, char *buf, int buflen)
{
    char *p = buf;
    int copied, len = 0;

    copied = CopyString(tgtPtr->pw_name, p, buflen - len);
    if (copied == -1) {
    range:
        errno = ERANGE;
        return -1;
    }
    tgtPtr->pw_name = (copied > 0) ? p : NULL;
    len += copied;
    p = buf + len;

    copied = CopyString(tgtPtr->pw_passwd, p, buflen - len);
    if (copied == -1) {
        goto range;
    }
    tgtPtr->pw_passwd = (copied > 0) ? p : NULL;
    len += copied;
    p = buf + len;

    copied = CopyString(tgtPtr->pw_dir, p, buflen - len);
    if (copied == -1) {
        goto range;
    }
    tgtPtr->pw_dir = (copied > 0) ? p : NULL;
    len += copied;
    p = buf + len;

    copied = CopyString(tgtPtr->pw_shell, p, buflen - len);
    if (copied == -1) {
        goto range;
    }
    tgtPtr->pw_shell = (copied > 0) ? p : NULL;

    return 0;
}
#endif /* !defined(HAVE_GETPWUID_R) */

#if !defined(HAVE_GETGRGID_R)

/*
 *---------------------------------------------------------------------------
 *
 * CopyGrp --
 *
 *      Copies string fields of the group structure to the 
 *      private buffer, honouring the size of the buffer.
 *
 * Results:
 *      0 on success or -1 on error (errno = ERANGE)
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

static int
CopyGrp(struct group *tgtPtr, char *buf, int buflen)
{
    register char *p = buf;
    register int copied, len = 0;

    /* Copy username */
    copied = CopyString(tgtPtr->gr_name, p, buflen - len);
    if (copied == -1) {
    range:
        errno = ERANGE;
        return -1;
    }
    tgtPtr->gr_name = (copied > 0) ? p : NULL;
    len += copied;
    p = buf + len;

    /* Copy password */
    copied = CopyString(tgtPtr->gr_passwd, p, buflen - len);
    if (copied == -1) {
        goto range;
    }
    tgtPtr->gr_passwd = (copied > 0) ? p : NULL;
    len += copied;
    p = buf + len;

    /* Copy group members */
    PadBuffer(p, len, sizeof(char *));
    copied = CopyArray((char **)tgtPtr->gr_mem, -1, p, buflen - len);
    if (copied == -1) {
        goto range;
    }
    tgtPtr->gr_mem = (copied > 0) ? (char **)p : NULL;

    return 0;
}
#endif /* !defined(HAVE_GETGRGID_R) */

#endif /* TCL_THREADS */


/*
 *---------------------------------------------------------------------------
 *
 * TclpGetPwNam --
 *
 *      Thread-safe wrappers for getpwnam().
 *      See "man getpwnam" for more details.
 *
 * Results:
 *      Pointer to struct passwd on success or NULL on error.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

struct passwd *
TclpGetPwNam(const char *name)
{
#if !defined(TCL_THREADS)
    return getpwnam(name);
#else
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

#if defined(HAVE_GETPWNAM_R_5)
    struct passwd *pwPtr = NULL;
    return (getpwnam_r(name, &tsdPtr->pwd, tsdPtr->pbuf, sizeof(tsdPtr->pbuf), 
                       &pwPtr) == 0 && pwPtr != NULL) ? &tsdPtr->pwd : NULL;

#elif defined(HAVE_GETPWNAM_R_4)
    return getpwnam_r(name, &tsdPtr->pwd, tsdPtr->pbuf, sizeof(tsdPtr->pbuf));

#else
    struct passwd *pwPtr;
    Tcl_MutexLock(&compatLock);
    pwPtr = getpwnam(name);
    if (pwPtr != NULL) {
        tsdPtr->pwd = *pwPtr;
        pwPtr = &tsdPtr->pwd;
        if (CopyPwd(&tsdPtr->pwd, tsdPtr->pbuf, sizeof(tsdPtr->pbuf)) == -1) {
            pwPtr = NULL;
        }
    }
    Tcl_MutexUnlock(&compatLock);
    return pwPtr;
#endif
    return NULL; /* Not reached */
#endif /* TCL_THREADS */
}


/*
 *---------------------------------------------------------------------------
 *
 * TclpGetPwUid --
 *
 *      Thread-safe wrappers for getpwuid().
 *      See "man getpwuid" for more details.
 *
 * Results:
 *      Pointer to struct passwd on success or NULL on error.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

struct passwd *
TclpGetPwUid(uid_t uid)
{
#if !defined(TCL_THREADS)
    return getpwuid(uid);
#else
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

#if defined(HAVE_GETPWUID_R_5)
    struct passwd *pwPtr = NULL;
    return (getpwuid_r(uid, &tsdPtr->pwd, tsdPtr->pbuf, sizeof(tsdPtr->pbuf),
                       &pwPtr) == 0 && pwPtr != NULL) ? &tsdPtr->pwd : NULL;

#elif defined(HAVE_GETPWUID_R_4)
    return getpwuid_r(uid, &tsdPtr->pwd, tsdPtr->pbuf, sizeof(tsdPtr->pbuf));

#else
    struct passwd *pwPtr;
    Tcl_MutexLock(&compatLock);
    pwPtr = getpwuid(uid);
    if (pwPtr != NULL) {
        tsdPtr->pwd = *pwPtr;
        pwPtr = &tsdPtr->pwd;
        if (CopyPwd(&tsdPtr->pwd, tsdPtr->pbuf, sizeof(tsdPtr->pbuf)) == -1) {
            pwPtr = NULL;
        }
    }
    Tcl_MutexUnlock(&compatLock);
    return pwPtr;
#endif
    return NULL; /* Not reached */
#endif /* TCL_THREADS */
}


/*
 *---------------------------------------------------------------------------
 *
 * TclpGetGrNam --
 *
 *      Thread-safe wrappers for getgrnam().
 *      See "man getgrnam" for more details.
 *
 * Results:
 *      Pointer to struct group on success or NULL on error.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

struct group *
TclpGetGrNam(const char *name)
{
#if !defined(TCL_THREADS)
    return getgrnam(name);
#else
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

#if defined(HAVE_GETGRNAM_R_5)
    struct group *grPtr = NULL;
    return (getgrnam_r(name, &tsdPtr->grp, tsdPtr->gbuf, sizeof(tsdPtr->gbuf),
                       &grPtr) == 0 && grPtr != NULL) ? &tsdPtr->grp : NULL;

#elif defined(HAVE_GETGRNAM_R_4)
    return getgrnam_r(name, &tsdPtr->grp, tsdPtr->gbuf, sizeof(tsdPtr->gbuf));

#else
    struct group *grPtr;
    Tcl_MutexLock(&compatLock);
    grPtr = getgrnam(name);
    if (grPtr != NULL) {
        tsdPtr->grp = *grPtr;
        grPtr = &tsdPtr->grp;
        if (CopyGrp(&tsdPtr->grp, tsdPtr->gbuf, sizeof(tsdPtr->gbuf)) == -1) {
            grPtr = NULL;
        }
    }
    Tcl_MutexUnlock(&compatLock);
    return grPtr;
#endif
    return NULL; /* Not reached */
#endif /* TCL_THREADS */
}


/*
 *---------------------------------------------------------------------------
 *
 * TclpGetGrGid --
 *
 *      Thread-safe wrappers for getgrgid().
 *      See "man getgrgid" for more details.
 *
 * Results:
 *      Pointer to struct group on success or NULL on error.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

struct group *
TclpGetGrGid(gid_t gid)
{
#if !defined(TCL_THREADS)
    return getgrgid(gid);
#else
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

#if defined(HAVE_GETGRGID_R_5)
    struct group *grPtr = NULL;
    return (getgrgid_r(gid, &tsdPtr->grp, tsdPtr->gbuf, sizeof(tsdPtr->gbuf),
                       &grPtr) == 0 && grPtr != NULL) ? &tsdPtr->grp : NULL;

#elif defined(HAVE_GETGRGID_R_4)
    return getgrgid_r(gid, &tsdPtr->grp, tsdPtr->gbuf, sizeof(tsdPtr->gbuf));

#else
    struct group *grPtr;
    Tcl_MutexLock(&compatLock);
    grPtr = getgrgid(gid);
    if (grPtr != NULL) {
        tsdPtr->grp = *grPtr;
        grPtr = &tsdPtr->grp;
        if (CopyGrp(&tsdPtr->grp, tsdPtr->gbuf, sizeof(tsdPtr->gbuf)) == -1) {
            grPtr = NULL;
        }
    }
    Tcl_MutexUnlock(&compatLock);
    return grPtr;
#endif
    return NULL; /* Not reached */
#endif /* TCL_THREADS */
}


/*
 *---------------------------------------------------------------------------
 *
 * TclpGetHostByName --
 *
 *      Thread-safe wrappers for gethostbyname().
 *      See "man gethostbyname" for more details.
 *
 * Results:
 *      Pointer to struct hostent on success or NULL on error.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

struct hostent *
TclpGetHostByName(const char *name)
{
#if !defined(TCL_THREADS)
    return gethostbyname(name);
#else
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

#if defined(HAVE_GETHOSTBYNAME_R_5)
    int h_errno;
    return gethostbyname_r(name, &tsdPtr->hent, tsdPtr->hbuf,
                           sizeof(tsdPtr->hbuf), &h_errno);
    
#elif defined(HAVE_GETHOSTBYNAME_R_6)
    struct hostent *hePtr;
    int h_errno;
    return (gethostbyname_r(name, &tsdPtr->hent, tsdPtr->hbuf,
                            sizeof(tsdPtr->hbuf), &hePtr, &h_errno) == 0) ? 
        &tsdPtr->hent : NULL;

#elif defined(HAVE_GETHOSTBYNAME_R_3)
    struct hostent_data data;
    return (gethostbyname_r(host, &tsdPtr->hent, &data) == 0) ?
        &tsdPtr->buf.hent : NULL;
#else
    struct hostent *hePtr;
    Tcl_MutexLock(&compatLock);
    hePtr = gethostbyname(name);
    if (hePtr != NULL) {
        tsdPtr->hent = *hePtr;
        hePtr = &tsdPtr->hent;
        if (CopyHostent(&tsdPtr->hent, tsdPtr->hbuf,
                        sizeof(tsdPtr->hbuf)) == -1) {
            hePtr = NULL;
        }
    }
    Tcl_MutexUnlock(&compatLock);
    return hePtr;
#endif
    return NULL; /* Not reached */
#endif /* TCL_THREADS */
}


/*
 *---------------------------------------------------------------------------
 *
 * TclpGetHostByAddr --
 *
 *      Thread-safe wrappers for gethostbyaddr().
 *      See "man gethostbyaddr" for more details.
 *
 * Results:
 *      Pointer to struct hostent on success or NULL on error.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

struct hostent *
TclpGetHostByAddr(const char *addr, int length, int type)
{
#if !defined(TCL_THREADS)
    return gethostbyaddr(addr, length, type);
#else
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

#if defined(HAVE_GETHOSTBYADDR_R_7)
    int h_errno;
    return gethostbyaddr_r(addr, length, type, &tsdPtr->hent, tsdPtr->hbuf,
                           sizeof(tsdPtr->hbuf), &h_errno);

#elif defined(HAVE_GETHOSTBYADDR_R_8)
    struct hostent *hePtr;
    int h_errno;
    return (gethostbyaddr_r(addr, length, type, &tsdPtr->hent, tsdPtr->hbuf,
                            sizeof(tsdPtr->hbuf), &hePtr, &h_errno) == 0) ? 
        &tsdPtr->hent : NULL;
#else
    struct hostent *hePtr;
    Tcl_MutexLock(&compatLock);
    hePtr = gethostbyaddr(addr, length, type);
    if (hePtr != NULL) {
        tsdPtr->hent = *hePtr;
        hePtr = &tsdPtr->hent;
        if (CopyHostent(&tsdPtr->hent, tsdPtr->hbuf, 
                        sizeof(tsdPtr->hbuf)) == -1) {
            hePtr = NULL;
        }
    }
    Tcl_MutexUnlock(&compatLock);
    return hePtr;
#endif
    return NULL; /* Not reached */
#endif /* TCL_THREADS */
}