summaryrefslogtreecommitdiff
path: root/Master/tlpkg/tlperl/lib/File/Temp.pm
blob: ac57c260c8ff4c0c0e67585823f064f6a2267454 (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
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
package File::Temp;

=head1 NAME

File::Temp - return name and handle of a temporary file safely

=begin __INTERNALS

=head1 PORTABILITY

This section is at the top in order to provide easier access to
porters.  It is not expected to be rendered by a standard pod
formatting tool. Please skip straight to the SYNOPSIS section if you
are not trying to port this module to a new platform.

This module is designed to be portable across operating systems and it
currently supports Unix, VMS, DOS, OS/2, Windows and Mac OS
(Classic). When porting to a new OS there are generally three main
issues that have to be solved:

=over 4

=item *

Can the OS unlink an open file? If it can not then the
C<_can_unlink_opened_file> method should be modified.

=item *

Are the return values from C<stat> reliable? By default all the
return values from C<stat> are compared when unlinking a temporary
file using the filename and the handle. Operating systems other than
unix do not always have valid entries in all fields. If utility function
C<File::Temp::unlink0> fails then the C<stat> comparison should be
modified accordingly.

=item *

Security. Systems that can not support a test for the sticky bit
on a directory can not use the MEDIUM and HIGH security tests.
The C<_can_do_level> method should be modified accordingly.

=back

=end __INTERNALS

=head1 SYNOPSIS

  use File::Temp qw/ tempfile tempdir /;

  $fh = tempfile();
  ($fh, $filename) = tempfile();

  ($fh, $filename) = tempfile( $template, DIR => $dir);
  ($fh, $filename) = tempfile( $template, SUFFIX => '.dat');
  ($fh, $filename) = tempfile( $template, TMPDIR => 1 );

  binmode( $fh, ":utf8" );

  $dir = tempdir( CLEANUP => 1 );
  ($fh, $filename) = tempfile( DIR => $dir );

Object interface:

  require File::Temp;
  use File::Temp ();
  use File::Temp qw/ :seekable /;

  $fh = File::Temp->new();
  $fname = $fh->filename;

  $fh = File::Temp->new(TEMPLATE => $template);
  $fname = $fh->filename;

  $tmp = File::Temp->new( UNLINK => 0, SUFFIX => '.dat' );
  print $tmp "Some data\n";
  print "Filename is $tmp\n";
  $tmp->seek( 0, SEEK_END );

The following interfaces are provided for compatibility with
existing APIs. They should not be used in new code.

MkTemp family:

  use File::Temp qw/ :mktemp  /;

  ($fh, $file) = mkstemp( "tmpfileXXXXX" );
  ($fh, $file) = mkstemps( "tmpfileXXXXXX", $suffix);

  $tmpdir = mkdtemp( $template );

  $unopened_file = mktemp( $template );

POSIX functions:

  use File::Temp qw/ :POSIX /;

  $file = tmpnam();
  $fh = tmpfile();

  ($fh, $file) = tmpnam();

Compatibility functions:

  $unopened_file = File::Temp::tempnam( $dir, $pfx );

=head1 DESCRIPTION

C<File::Temp> can be used to create and open temporary files in a safe
way.  There is both a function interface and an object-oriented
interface.  The File::Temp constructor or the tempfile() function can
be used to return the name and the open filehandle of a temporary
file.  The tempdir() function can be used to create a temporary
directory.

The security aspect of temporary file creation is emphasized such that
a filehandle and filename are returned together.  This helps guarantee
that a race condition can not occur where the temporary file is
created by another process between checking for the existence of the
file and its opening.  Additional security levels are provided to
check, for example, that the sticky bit is set on world writable
directories.  See L<"safe_level"> for more information.

For compatibility with popular C library functions, Perl implementations of
the mkstemp() family of functions are provided. These are, mkstemp(),
mkstemps(), mkdtemp() and mktemp().

Additionally, implementations of the standard L<POSIX|POSIX>
tmpnam() and tmpfile() functions are provided if required.

Implementations of mktemp(), tmpnam(), and tempnam() are provided,
but should be used with caution since they return only a filename
that was valid when function was called, so cannot guarantee
that the file will not exist by the time the caller opens the filename.

Filehandles returned by these functions support the seekable methods.

=cut

# 5.6.0 gives us S_IWOTH, S_IWGRP, our and auto-vivifying filehandls
# People would like a version on 5.004 so give them what they want :-)
use 5.004;
use strict;
use Carp;
use File::Spec 0.8;
use Cwd ();
use File::Path qw/ rmtree /;
use Fcntl 1.03;
use IO::Seekable;               # For SEEK_*
use Errno;
use Scalar::Util 'refaddr';
require VMS::Stdio if $^O eq 'VMS';

# pre-emptively load Carp::Heavy. If we don't when we run out of file
# handles and attempt to call croak() we get an error message telling
# us that Carp::Heavy won't load rather than an error telling us we
# have run out of file handles. We either preload croak() or we
# switch the calls to croak from _gettemp() to use die.
eval { require Carp::Heavy; };

# Need the Symbol package if we are running older perl
require Symbol if $] < 5.006;

### For the OO interface
use base qw/ IO::Handle IO::Seekable /;
use overload '""' => "STRINGIFY", '0+' => "NUMIFY",
  fallback => 1;

# use 'our' on v5.6.0
use vars qw($VERSION @EXPORT_OK %EXPORT_TAGS $DEBUG $KEEP_ALL);

$DEBUG = 0;
$KEEP_ALL = 0;

# We are exporting functions

use base qw/Exporter/;

# Export list - to allow fine tuning of export table

@EXPORT_OK = qw{
                 tempfile
                 tempdir
                 tmpnam
                 tmpfile
                 mktemp
                 mkstemp
                 mkstemps
                 mkdtemp
                 unlink0
                 cleanup
                 SEEK_SET
                 SEEK_CUR
                 SEEK_END
             };

# Groups of functions for export

%EXPORT_TAGS = (
                'POSIX' => [qw/ tmpnam tmpfile /],
                'mktemp' => [qw/ mktemp mkstemp mkstemps mkdtemp/],
                'seekable' => [qw/ SEEK_SET SEEK_CUR SEEK_END /],
               );

# add contents of these tags to @EXPORT
Exporter::export_tags('POSIX','mktemp','seekable');

# Version number

$VERSION = '0.23';

# This is a list of characters that can be used in random filenames

my @CHARS = (qw/ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
                 a b c d e f g h i j k l m n o p q r s t u v w x y z
                 0 1 2 3 4 5 6 7 8 9 _
               /);

# Maximum number of tries to make a temp file before failing

use constant MAX_TRIES => 1000;

# Minimum number of X characters that should be in a template
use constant MINX => 4;

# Default template when no template supplied

use constant TEMPXXX => 'X' x 10;

# Constants for the security level

use constant STANDARD => 0;
use constant MEDIUM   => 1;
use constant HIGH     => 2;

# OPENFLAGS. If we defined the flag to use with Sysopen here this gives
# us an optimisation when many temporary files are requested

my $OPENFLAGS = O_CREAT | O_EXCL | O_RDWR;
my $LOCKFLAG;

unless ($^O eq 'MacOS') {
  for my $oflag (qw/ NOFOLLOW BINARY LARGEFILE NOINHERIT /) {
    my ($bit, $func) = (0, "Fcntl::O_" . $oflag);
    no strict 'refs';
    $OPENFLAGS |= $bit if eval {
      # Make sure that redefined die handlers do not cause problems
      # e.g. CGI::Carp
      local $SIG{__DIE__} = sub {};
      local $SIG{__WARN__} = sub {};
      $bit = &$func();
      1;
    };
  }
  # Special case O_EXLOCK
  $LOCKFLAG = eval {
    local $SIG{__DIE__} = sub {};
    local $SIG{__WARN__} = sub {};
    &Fcntl::O_EXLOCK();
  };
}

# On some systems the O_TEMPORARY flag can be used to tell the OS
# to automatically remove the file when it is closed. This is fine
# in most cases but not if tempfile is called with UNLINK=>0 and
# the filename is requested -- in the case where the filename is to
# be passed to another routine. This happens on windows. We overcome
# this by using a second open flags variable

my $OPENTEMPFLAGS = $OPENFLAGS;
unless ($^O eq 'MacOS') {
  for my $oflag (qw/ TEMPORARY /) {
    my ($bit, $func) = (0, "Fcntl::O_" . $oflag);
    local($@);
    no strict 'refs';
    $OPENTEMPFLAGS |= $bit if eval {
      # Make sure that redefined die handlers do not cause problems
      # e.g. CGI::Carp
      local $SIG{__DIE__} = sub {};
      local $SIG{__WARN__} = sub {};
      $bit = &$func();
      1;
    };
  }
}

# Private hash tracking which files have been created by each process id via the OO interface
my %FILES_CREATED_BY_OBJECT;

# INTERNAL ROUTINES - not to be used outside of package

# Generic routine for getting a temporary filename
# modelled on OpenBSD _gettemp() in mktemp.c

# The template must contain X's that are to be replaced
# with the random values

#  Arguments:

#  TEMPLATE   - string containing the XXXXX's that is converted
#           to a random filename and opened if required

# Optionally, a hash can also be supplied containing specific options
#   "open" => if true open the temp file, else just return the name
#             default is 0
#   "mkdir"=> if true, we are creating a temp directory rather than tempfile
#             default is 0
#   "suffixlen" => number of characters at end of PATH to be ignored.
#                  default is 0.
#   "unlink_on_close" => indicates that, if possible,  the OS should remove
#                        the file as soon as it is closed. Usually indicates
#                        use of the O_TEMPORARY flag to sysopen.
#                        Usually irrelevant on unix
#   "use_exlock" => Indicates that O_EXLOCK should be used. Default is true.

# Optionally a reference to a scalar can be passed into the function
# On error this will be used to store the reason for the error
#   "ErrStr"  => \$errstr

# "open" and "mkdir" can not both be true
# "unlink_on_close" is not used when "mkdir" is true.

# The default options are equivalent to mktemp().

# Returns:
#   filehandle - open file handle (if called with doopen=1, else undef)
#   temp name  - name of the temp file or directory

# For example:
#   ($fh, $name) = _gettemp($template, "open" => 1);

# for the current version, failures are associated with
# stored in an error string and returned to give the reason whilst debugging
# This routine is not called by any external function
sub _gettemp {

  croak 'Usage: ($fh, $name) = _gettemp($template, OPTIONS);'
    unless scalar(@_) >= 1;

  # the internal error string - expect it to be overridden
  # Need this in case the caller decides not to supply us a value
  # need an anonymous scalar
  my $tempErrStr;

  # Default options
  my %options = (
                 "open" => 0,
                 "mkdir" => 0,
                 "suffixlen" => 0,
                 "unlink_on_close" => 0,
                 "use_exlock" => 1,
                 "ErrStr" => \$tempErrStr,
                );

  # Read the template
  my $template = shift;
  if (ref($template)) {
    # Use a warning here since we have not yet merged ErrStr
    carp "File::Temp::_gettemp: template must not be a reference";
    return ();
  }

  # Check that the number of entries on stack are even
  if (scalar(@_) % 2 != 0) {
    # Use a warning here since we have not yet merged ErrStr
    carp "File::Temp::_gettemp: Must have even number of options";
    return ();
  }

  # Read the options and merge with defaults
  %options = (%options, @_)  if @_;

  # Make sure the error string is set to undef
  ${$options{ErrStr}} = undef;

  # Can not open the file and make a directory in a single call
  if ($options{"open"} && $options{"mkdir"}) {
    ${$options{ErrStr}} = "doopen and domkdir can not both be true\n";
    return ();
  }

  # Find the start of the end of the  Xs (position of last X)
  # Substr starts from 0
  my $start = length($template) - 1 - $options{"suffixlen"};

  # Check that we have at least MINX x X (e.g. 'XXXX") at the end of the string
  # (taking suffixlen into account). Any fewer is insecure.

  # Do it using substr - no reason to use a pattern match since
  # we know where we are looking and what we are looking for

  if (substr($template, $start - MINX + 1, MINX) ne 'X' x MINX) {
    ${$options{ErrStr}} = "The template must end with at least ".
      MINX . " 'X' characters\n";
    return ();
  }

  # Replace all the X at the end of the substring with a
  # random character or just all the XX at the end of a full string.
  # Do it as an if, since the suffix adjusts which section to replace
  # and suffixlen=0 returns nothing if used in the substr directly
  # and generate a full path from the template

  my $path = _replace_XX($template, $options{"suffixlen"});


  # Split the path into constituent parts - eventually we need to check
  # whether the directory exists
  # We need to know whether we are making a temp directory
  # or a tempfile

  my ($volume, $directories, $file);
  my $parent;                   # parent directory
  if ($options{"mkdir"}) {
    # There is no filename at the end
    ($volume, $directories, $file) = File::Spec->splitpath( $path, 1);

    # The parent is then $directories without the last directory
    # Split the directory and put it back together again
    my @dirs = File::Spec->splitdir($directories);

    # If @dirs only has one entry (i.e. the directory template) that means
    # we are in the current directory
    if ($#dirs == 0) {
      $parent = File::Spec->curdir;
    } else {

      if ($^O eq 'VMS') {     # need volume to avoid relative dir spec
        $parent = File::Spec->catdir($volume, @dirs[0..$#dirs-1]);
        $parent = 'sys$disk:[]' if $parent eq '';
      } else {

        # Put it back together without the last one
        $parent = File::Spec->catdir(@dirs[0..$#dirs-1]);

        # ...and attach the volume (no filename)
        $parent = File::Spec->catpath($volume, $parent, '');
      }

    }

  } else {

    # Get rid of the last filename (use File::Basename for this?)
    ($volume, $directories, $file) = File::Spec->splitpath( $path );

    # Join up without the file part
    $parent = File::Spec->catpath($volume,$directories,'');

    # If $parent is empty replace with curdir
    $parent = File::Spec->curdir
      unless $directories ne '';

  }

  # Check that the parent directories exist
  # Do this even for the case where we are simply returning a name
  # not a file -- no point returning a name that includes a directory
  # that does not exist or is not writable

  unless (-e $parent) {
    ${$options{ErrStr}} = "Parent directory ($parent) does not exist";
    return ();
  }
  unless (-d $parent) {
    ${$options{ErrStr}} = "Parent directory ($parent) is not a directory";
    return ();
  }

  # Check the stickiness of the directory and chown giveaway if required
  # If the directory is world writable the sticky bit
  # must be set

  if (File::Temp->safe_level == MEDIUM) {
    my $safeerr;
    unless (_is_safe($parent,\$safeerr)) {
      ${$options{ErrStr}} = "Parent directory ($parent) is not safe ($safeerr)";
      return ();
    }
  } elsif (File::Temp->safe_level == HIGH) {
    my $safeerr;
    unless (_is_verysafe($parent, \$safeerr)) {
      ${$options{ErrStr}} = "Parent directory ($parent) is not safe ($safeerr)";
      return ();
    }
  }


  # Now try MAX_TRIES time to open the file
  for (my $i = 0; $i < MAX_TRIES; $i++) {

    # Try to open the file if requested
    if ($options{"open"}) {
      my $fh;

      # If we are running before perl5.6.0 we can not auto-vivify
      if ($] < 5.006) {
        $fh = &Symbol::gensym;
      }

      # Try to make sure this will be marked close-on-exec
      # XXX: Win32 doesn't respect this, nor the proper fcntl,
      #      but may have O_NOINHERIT. This may or may not be in Fcntl.
      local $^F = 2;

      # Attempt to open the file
      my $open_success = undef;
      if ( $^O eq 'VMS' and $options{"unlink_on_close"} && !$KEEP_ALL) {
        # make it auto delete on close by setting FAB$V_DLT bit
        $fh = VMS::Stdio::vmssysopen($path, $OPENFLAGS, 0600, 'fop=dlt');
        $open_success = $fh;
      } else {
        my $flags = ( ($options{"unlink_on_close"} && !$KEEP_ALL) ?
                      $OPENTEMPFLAGS :
                      $OPENFLAGS );
        $flags |= $LOCKFLAG if (defined $LOCKFLAG && $options{use_exlock});
        $open_success = sysopen($fh, $path, $flags, 0600);
      }
      if ( $open_success ) {

        # in case of odd umask force rw
        chmod(0600, $path);

        # Opened successfully - return file handle and name
        return ($fh, $path);

      } else {

        # Error opening file - abort with error
        # if the reason was anything but EEXIST
        unless ($!{EEXIST}) {
          ${$options{ErrStr}} = "Could not create temp file $path: $!";
          return ();
        }

        # Loop round for another try

      }
    } elsif ($options{"mkdir"}) {

      # Open the temp directory
      if (mkdir( $path, 0700)) {
        # in case of odd umask
        chmod(0700, $path);

        return undef, $path;
      } else {

        # Abort with error if the reason for failure was anything
        # except EEXIST
        unless ($!{EEXIST}) {
          ${$options{ErrStr}} = "Could not create directory $path: $!";
          return ();
        }

        # Loop round for another try

      }

    } else {

      # Return true if the file can not be found
      # Directory has been checked previously

      return (undef, $path) unless -e $path;

      # Try again until MAX_TRIES

    }

    # Did not successfully open the tempfile/dir
    # so try again with a different set of random letters
    # No point in trying to increment unless we have only
    # 1 X say and the randomness could come up with the same
    # file MAX_TRIES in a row.

    # Store current attempt - in principal this implies that the
    # 3rd time around the open attempt that the first temp file
    # name could be generated again. Probably should store each
    # attempt and make sure that none are repeated

    my $original = $path;
    my $counter = 0;            # Stop infinite loop
    my $MAX_GUESS = 50;

    do {

      # Generate new name from original template
      $path = _replace_XX($template, $options{"suffixlen"});

      $counter++;

    } until ($path ne $original || $counter > $MAX_GUESS);

    # Check for out of control looping
    if ($counter > $MAX_GUESS) {
      ${$options{ErrStr}} = "Tried to get a new temp name different to the previous value $MAX_GUESS times.\nSomething wrong with template?? ($template)";
      return ();
    }

  }

  # If we get here, we have run out of tries
  ${ $options{ErrStr} } = "Have exceeded the maximum number of attempts ("
    . MAX_TRIES . ") to open temp file/dir";

  return ();

}

# Internal routine to replace the XXXX... with random characters
# This has to be done by _gettemp() every time it fails to
# open a temp file/dir

# Arguments:  $template (the template with XXX),
#             $ignore   (number of characters at end to ignore)

# Returns:    modified template

sub _replace_XX {

  croak 'Usage: _replace_XX($template, $ignore)'
    unless scalar(@_) == 2;

  my ($path, $ignore) = @_;

  # Do it as an if, since the suffix adjusts which section to replace
  # and suffixlen=0 returns nothing if used in the substr directly
  # Alternatively, could simply set $ignore to length($path)-1
  # Don't want to always use substr when not required though.
  my $end = ( $] >= 5.006 ? "\\z" : "\\Z" );

  if ($ignore) {
    substr($path, 0, - $ignore) =~ s/X(?=X*$end)/$CHARS[ int( rand( @CHARS ) ) ]/ge;
  } else {
    $path =~ s/X(?=X*$end)/$CHARS[ int( rand( @CHARS ) ) ]/ge;
  }
  return $path;
}

# Internal routine to force a temp file to be writable after
# it is created so that we can unlink it. Windows seems to occasionally
# force a file to be readonly when written to certain temp locations
sub _force_writable {
  my $file = shift;
  chmod 0600, $file;
}


# internal routine to check to see if the directory is safe
# First checks to see if the directory is not owned by the
# current user or root. Then checks to see if anyone else
# can write to the directory and if so, checks to see if
# it has the sticky bit set

# Will not work on systems that do not support sticky bit

#Args:  directory path to check
#       Optionally: reference to scalar to contain error message
# Returns true if the path is safe and false otherwise.
# Returns undef if can not even run stat() on the path

# This routine based on version written by Tom Christiansen

# Presumably, by the time we actually attempt to create the
# file or directory in this directory, it may not be safe
# anymore... Have to run _is_safe directly after the open.

sub _is_safe {

  my $path = shift;
  my $err_ref = shift;

  # Stat path
  my @info = stat($path);
  unless (scalar(@info)) {
    $$err_ref = "stat(path) returned no values";
    return 0;
  }
  ;
  return 1 if $^O eq 'VMS';     # owner delete control at file level

  # Check to see whether owner is neither superuser (or a system uid) nor me
  # Use the effective uid from the $> variable
  # UID is in [4]
  if ($info[4] > File::Temp->top_system_uid() && $info[4] != $>) {

    Carp::cluck(sprintf "uid=$info[4] topuid=%s euid=$> path='$path'",
                File::Temp->top_system_uid());

    $$err_ref = "Directory owned neither by root nor the current user"
      if ref($err_ref);
    return 0;
  }

  # check whether group or other can write file
  # use 066 to detect either reading or writing
  # use 022 to check writability
  # Do it with S_IWOTH and S_IWGRP for portability (maybe)
  # mode is in info[2]
  if (($info[2] & &Fcntl::S_IWGRP) ||  # Is group writable?
      ($info[2] & &Fcntl::S_IWOTH) ) { # Is world writable?
    # Must be a directory
    unless (-d $path) {
      $$err_ref = "Path ($path) is not a directory"
        if ref($err_ref);
      return 0;
    }
    # Must have sticky bit set
    unless (-k $path) {
      $$err_ref = "Sticky bit not set on $path when dir is group|world writable"
        if ref($err_ref);
      return 0;
    }
  }

  return 1;
}

# Internal routine to check whether a directory is safe
# for temp files. Safer than _is_safe since it checks for
# the possibility of chown giveaway and if that is a possibility
# checks each directory in the path to see if it is safe (with _is_safe)

# If _PC_CHOWN_RESTRICTED is not set, does the full test of each
# directory anyway.

# Takes optional second arg as scalar ref to error reason

sub _is_verysafe {

  # Need POSIX - but only want to bother if really necessary due to overhead
  require POSIX;

  my $path = shift;
  print "_is_verysafe testing $path\n" if $DEBUG;
  return 1 if $^O eq 'VMS';     # owner delete control at file level

  my $err_ref = shift;

  # Should Get the value of _PC_CHOWN_RESTRICTED if it is defined
  # and If it is not there do the extensive test
  local($@);
  my $chown_restricted;
  $chown_restricted = &POSIX::_PC_CHOWN_RESTRICTED()
    if eval { &POSIX::_PC_CHOWN_RESTRICTED(); 1};

  # If chown_resticted is set to some value we should test it
  if (defined $chown_restricted) {

    # Return if the current directory is safe
    return _is_safe($path,$err_ref) if POSIX::sysconf( $chown_restricted );

  }

  # To reach this point either, the _PC_CHOWN_RESTRICTED symbol
  # was not available or the symbol was there but chown giveaway
  # is allowed. Either way, we now have to test the entire tree for
  # safety.

  # Convert path to an absolute directory if required
  unless (File::Spec->file_name_is_absolute($path)) {
    $path = File::Spec->rel2abs($path);
  }

  # Split directory into components - assume no file
  my ($volume, $directories, undef) = File::Spec->splitpath( $path, 1);

  # Slightly less efficient than having a function in File::Spec
  # to chop off the end of a directory or even a function that
  # can handle ../ in a directory tree
  # Sometimes splitdir() returns a blank at the end
  # so we will probably check the bottom directory twice in some cases
  my @dirs = File::Spec->splitdir($directories);

  # Concatenate one less directory each time around
  foreach my $pos (0.. $#dirs) {
    # Get a directory name
    my $dir = File::Spec->catpath($volume,
                                  File::Spec->catdir(@dirs[0.. $#dirs - $pos]),
                                  ''
                                 );

    print "TESTING DIR $dir\n" if $DEBUG;

    # Check the directory
    return 0 unless _is_safe($dir,$err_ref);

  }

  return 1;
}



# internal routine to determine whether unlink works on this
# platform for files that are currently open.
# Returns true if we can, false otherwise.

# Currently WinNT, OS/2 and VMS can not unlink an opened file
# On VMS this is because the O_EXCL flag is used to open the
# temporary file. Currently I do not know enough about the issues
# on VMS to decide whether O_EXCL is a requirement.

sub _can_unlink_opened_file {

  if (grep { $^O eq $_ } qw/MSWin32 os2 VMS dos MacOS haiku/) {
    return 0;
  } else {
    return 1;
  }

}

# internal routine to decide which security levels are allowed
# see safe_level() for more information on this

# Controls whether the supplied security level is allowed

#   $cando = _can_do_level( $level )

sub _can_do_level {

  # Get security level
  my $level = shift;

  # Always have to be able to do STANDARD
  return 1 if $level == STANDARD;

  # Currently, the systems that can do HIGH or MEDIUM are identical
  if ( $^O eq 'MSWin32' || $^O eq 'os2' || $^O eq 'cygwin' || $^O eq 'dos' || $^O eq 'MacOS' || $^O eq 'mpeix') {
    return 0;
  } else {
    return 1;
  }

}

# This routine sets up a deferred unlinking of a specified
# filename and filehandle. It is used in the following cases:
#  - Called by unlink0 if an opened file can not be unlinked
#  - Called by tempfile() if files are to be removed on shutdown
#  - Called by tempdir() if directories are to be removed on shutdown

# Arguments:
#   _deferred_unlink( $fh, $fname, $isdir );
#
#   - filehandle (so that it can be explicitly closed if open
#   - filename   (the thing we want to remove)
#   - isdir      (flag to indicate that we are being given a directory)
#                 [and hence no filehandle]

# Status is not referred to since all the magic is done with an END block

{
  # Will set up two lexical variables to contain all the files to be
  # removed. One array for files, another for directories They will
  # only exist in this block.

  #  This means we only have to set up a single END block to remove
  #  all files. 

  # in order to prevent child processes inadvertently deleting the parent
  # temp files we use a hash to store the temp files and directories
  # created by a particular process id.

  # %files_to_unlink contains values that are references to an array of
  # array references containing the filehandle and filename associated with
  # the temp file.
  my (%files_to_unlink, %dirs_to_unlink);

  # Set up an end block to use these arrays
  END {
    local($., $@, $!, $^E, $?);
    cleanup(at_exit => 1);
  }

  # Cleanup function. Always triggered on END (with at_exit => 1) but
  # can be invoked manually.
  sub cleanup {
    my %h = @_;
    my $at_exit = delete $h{at_exit};
    $at_exit = 0 if not defined $at_exit;
    { my @k = sort keys %h; die "unrecognized parameters: @k" if @k }

    if (!$KEEP_ALL) {
      # Files
      my @files = (exists $files_to_unlink{$$} ?
                   @{ $files_to_unlink{$$} } : () );
      foreach my $file (@files) {
        # close the filehandle without checking its state
        # in order to make real sure that this is closed
        # if its already closed then I dont care about the answer
        # probably a better way to do this
        close($file->[0]);      # file handle is [0]

        if (-f $file->[1]) {       # file name is [1]
          _force_writable( $file->[1] ); # for windows
          unlink $file->[1] or warn "Error removing ".$file->[1];
        }
      }
      # Dirs
      my @dirs = (exists $dirs_to_unlink{$$} ?
                  @{ $dirs_to_unlink{$$} } : () );
      my ($cwd, $cwd_to_remove);
      foreach my $dir (@dirs) {
        if (-d $dir) {
          # Some versions of rmtree will abort if you attempt to remove
          # the directory you are sitting in. For automatic cleanup
          # at program exit, we avoid this by chdir()ing out of the way
          # first. If not at program exit, it's best not to mess with the
          # current directory, so just let it fail with a warning.
          if ($at_exit) {
            $cwd = Cwd::abs_path(File::Spec->curdir) if not defined $cwd;
            my $abs = Cwd::abs_path($dir);
            if ($abs eq $cwd) {
              $cwd_to_remove = $dir;
              next;
            }
          }
          eval { rmtree($dir, $DEBUG, 0); };
          warn $@ if ($@ && $^W);
        }
      }

      if (defined $cwd_to_remove) {
        # We do need to clean up the current directory, and everything
        # else is done, so get out of there and remove it.
        chdir $cwd_to_remove or die "cannot chdir to $cwd_to_remove: $!";
        my $updir = File::Spec->updir;
        chdir $updir or die "cannot chdir to $updir: $!";
        eval { rmtree($cwd_to_remove, $DEBUG, 0); };
        warn $@ if ($@ && $^W);
      }

      # clear the arrays
      @{ $files_to_unlink{$$} } = ()
        if exists $files_to_unlink{$$};
      @{ $dirs_to_unlink{$$} } = ()
        if exists $dirs_to_unlink{$$};
    }
  }


  # This is the sub called to register a file for deferred unlinking
  # This could simply store the input parameters and defer everything
  # until the END block. For now we do a bit of checking at this
  # point in order to make sure that (1) we have a file/dir to delete
  # and (2) we have been called with the correct arguments.
  sub _deferred_unlink {

    croak 'Usage:  _deferred_unlink($fh, $fname, $isdir)'
      unless scalar(@_) == 3;

    my ($fh, $fname, $isdir) = @_;

    warn "Setting up deferred removal of $fname\n"
      if $DEBUG;

    # make sure we save the absolute path for later cleanup
    # OK to untaint because we only ever use this internally
    # as a file path, never interpolating into the shell
    $fname = Cwd::abs_path($fname);
    ($fname) = $fname =~ /^(.*)$/;

    # If we have a directory, check that it is a directory
    if ($isdir) {

      if (-d $fname) {

        # Directory exists so store it
        # first on VMS turn []foo into [.foo] for rmtree
        $fname = VMS::Filespec::vmspath($fname) if $^O eq 'VMS';
        $dirs_to_unlink{$$} = [] 
          unless exists $dirs_to_unlink{$$};
        push (@{ $dirs_to_unlink{$$} }, $fname);

      } else {
        carp "Request to remove directory $fname could not be completed since it does not exist!\n" if $^W;
      }

    } else {

      if (-f $fname) {

        # file exists so store handle and name for later removal
        $files_to_unlink{$$} = []
          unless exists $files_to_unlink{$$};
        push(@{ $files_to_unlink{$$} }, [$fh, $fname]);

      } else {
        carp "Request to remove file $fname could not be completed since it is not there!\n" if $^W;
      }

    }

  }


}

# normalize argument keys to upper case and do consistent handling
# of leading template vs TEMPLATE
sub _parse_args {
  my $leading_template = (scalar(@_) % 2 == 1 ? shift(@_) : '' );
  my %args = @_;
  %args = map { uc($_), $args{$_} } keys %args;

  # template (store it in an array so that it will
  # disappear from the arg list of tempfile)
  my @template = (
    exists $args{TEMPLATE}  ? $args{TEMPLATE} :
    $leading_template       ? $leading_template : ()
  );
  delete $args{TEMPLATE};

  return( \@template, \%args );
}

=head1 OBJECT-ORIENTED INTERFACE

This is the primary interface for interacting with
C<File::Temp>. Using the OO interface a temporary file can be created
when the object is constructed and the file can be removed when the
object is no longer required.

Note that there is no method to obtain the filehandle from the
C<File::Temp> object. The object itself acts as a filehandle.  The object
isa C<IO::Handle> and isa C<IO::Seekable> so all those methods are
available.

Also, the object is configured such that it stringifies to the name of the
temporary file and so can be compared to a filename directly.  It numifies
to the C<refaddr> the same as other handles and so can be compared to other
handles with C<==>.

    $fh eq $filename       # as a string
    $fh != \*STDOUT        # as a number

=over 4

=item B<new>

Create a temporary file object.

  my $tmp = File::Temp->new();

by default the object is constructed as if C<tempfile>
was called without options, but with the additional behaviour
that the temporary file is removed by the object destructor
if UNLINK is set to true (the default).

Supported arguments are the same as for C<tempfile>: UNLINK
(defaulting to true), DIR, EXLOCK and SUFFIX. Additionally, the filename
template is specified using the TEMPLATE option. The OPEN option
is not supported (the file is always opened).

 $tmp = File::Temp->new( TEMPLATE => 'tempXXXXX',
                        DIR => 'mydir',
                        SUFFIX => '.dat');

Arguments are case insensitive.

Can call croak() if an error occurs.

=cut

sub new {
  my $proto = shift;
  my $class = ref($proto) || $proto;

  my ($maybe_template, $args) = _parse_args(@_);

  # see if they are unlinking (defaulting to yes)
  my $unlink = (exists $args->{UNLINK} ? $args->{UNLINK} : 1 );
  delete $args->{UNLINK};

  # Protect OPEN
  delete $args->{OPEN};

  # Open the file and retain file handle and file name
  my ($fh, $path) = tempfile( @$maybe_template, %$args );

  print "Tmp: $fh - $path\n" if $DEBUG;

  # Store the filename in the scalar slot
  ${*$fh} = $path;

  # Cache the filename by pid so that the destructor can decide whether to remove it
  $FILES_CREATED_BY_OBJECT{$$}{$path} = 1;

  # Store unlink information in hash slot (plus other constructor info)
  %{*$fh} = %$args;

  # create the object
  bless $fh, $class;

  # final method-based configuration
  $fh->unlink_on_destroy( $unlink );

  return $fh;
}

=item B<newdir>

Create a temporary directory using an object oriented interface.

  $dir = File::Temp->newdir();

By default the directory is deleted when the object goes out of scope.

Supports the same options as the C<tempdir> function. Note that directories
created with this method default to CLEANUP => 1.

  $dir = File::Temp->newdir( $template, %options );

A template may be specified either with a leading template or
with a TEMPLATE argument.

=cut

sub newdir {
  my $self = shift;

  my ($maybe_template, $args) = _parse_args(@_);

  # handle CLEANUP without passing CLEANUP to tempdir
  my $cleanup = (exists $args->{CLEANUP} ? $args->{CLEANUP} : 1 );
  delete $args->{CLEANUP};

  my $tempdir = tempdir( @$maybe_template, %$args);

  # get a safe absolute path for cleanup, just like
  # happens in _deferred_unlink
  my $real_dir = Cwd::abs_path( $tempdir );
  ($real_dir) = $real_dir =~ /^(.*)$/;

  return bless { DIRNAME => $tempdir,
                 REALNAME => $real_dir,
                 CLEANUP => $cleanup,
                 LAUNCHPID => $$,
               }, "File::Temp::Dir";
}

=item B<filename>

Return the name of the temporary file associated with this object
(if the object was created using the "new" constructor).

  $filename = $tmp->filename;

This method is called automatically when the object is used as
a string.

=cut

sub filename {
  my $self = shift;
  return ${*$self};
}

sub STRINGIFY {
  my $self = shift;
  return $self->filename;
}

# For reference, can't use '0+'=>\&Scalar::Util::refaddr directly because
# refaddr() demands one parameter only, whereas overload.pm calls with three
# even for unary operations like '0+'.
sub NUMIFY {
  return refaddr($_[0]);
}

=item B<dirname>

Return the name of the temporary directory associated with this
object (if the object was created using the "newdir" constructor).

  $dirname = $tmpdir->dirname;

This method is called automatically when the object is used in string context.

=item B<unlink_on_destroy>

Control whether the file is unlinked when the object goes out of scope.
The file is removed if this value is true and $KEEP_ALL is not.

 $fh->unlink_on_destroy( 1 );

Default is for the file to be removed.

=cut

sub unlink_on_destroy {
  my $self = shift;
  if (@_) {
    ${*$self}{UNLINK} = shift;
  }
  return ${*$self}{UNLINK};
}

=item B<DESTROY>

When the object goes out of scope, the destructor is called. This
destructor will attempt to unlink the file (using L<unlink1|"unlink1">)
if the constructor was called with UNLINK set to 1 (the default state
if UNLINK is not specified).

No error is given if the unlink fails.

If the object has been passed to a child process during a fork, the
file will be deleted when the object goes out of scope in the parent.

For a temporary directory object the directory will be removed unless
the CLEANUP argument was used in the constructor (and set to false) or
C<unlink_on_destroy> was modified after creation.  Note that if a temp
directory is your current directory, it cannot be removed - a warning
will be given in this case.  C<chdir()> out of the directory before
letting the object go out of scope.

If the global variable $KEEP_ALL is true, the file or directory
will not be removed.

=cut

sub DESTROY {
  local($., $@, $!, $^E, $?);
  my $self = shift;

  # Make sure we always remove the file from the global hash
  # on destruction. This prevents the hash from growing uncontrollably
  # and post-destruction there is no reason to know about the file.
  my $file = $self->filename;
  my $was_created_by_proc;
  if (exists $FILES_CREATED_BY_OBJECT{$$}{$file}) {
    $was_created_by_proc = 1;
    delete $FILES_CREATED_BY_OBJECT{$$}{$file};
  }

  if (${*$self}{UNLINK} && !$KEEP_ALL) {
    print "# --------->   Unlinking $self\n" if $DEBUG;

    # only delete if this process created it
    return unless $was_created_by_proc;

    # The unlink1 may fail if the file has been closed
    # by the caller. This leaves us with the decision
    # of whether to refuse to remove the file or simply
    # do an unlink without test. Seems to be silly
    # to do this when we are trying to be careful
    # about security
    _force_writable( $file ); # for windows
    unlink1( $self, $file )
      or unlink($file);
  }
}

=back

=head1 FUNCTIONS

This section describes the recommended interface for generating
temporary files and directories.

=over 4

=item B<tempfile>

This is the basic function to generate temporary files.
The behaviour of the file can be changed using various options:

  $fh = tempfile();
  ($fh, $filename) = tempfile();

Create a temporary file in  the directory specified for temporary
files, as specified by the tmpdir() function in L<File::Spec>.

  ($fh, $filename) = tempfile($template);

Create a temporary file in the current directory using the supplied
template.  Trailing `X' characters are replaced with random letters to
generate the filename.  At least four `X' characters must be present
at the end of the template.

  ($fh, $filename) = tempfile($template, SUFFIX => $suffix)

Same as previously, except that a suffix is added to the template
after the `X' translation.  Useful for ensuring that a temporary
filename has a particular extension when needed by other applications.
But see the WARNING at the end.

  ($fh, $filename) = tempfile($template, DIR => $dir);

Translates the template as before except that a directory name
is specified.

  ($fh, $filename) = tempfile($template, TMPDIR => 1);

Equivalent to specifying a DIR of "File::Spec->tmpdir", writing the file
into the same temporary directory as would be used if no template was
specified at all.

  ($fh, $filename) = tempfile($template, UNLINK => 1);

Return the filename and filehandle as before except that the file is
automatically removed when the program exits (dependent on
$KEEP_ALL). Default is for the file to be removed if a file handle is
requested and to be kept if the filename is requested. In a scalar
context (where no filename is returned) the file is always deleted
either (depending on the operating system) on exit or when it is
closed (unless $KEEP_ALL is true when the temp file is created).

Use the object-oriented interface if fine-grained control of when
a file is removed is required.

If the template is not specified, a template is always
automatically generated. This temporary file is placed in tmpdir()
(L<File::Spec>) unless a directory is specified explicitly with the
DIR option.

  $fh = tempfile( DIR => $dir );

If called in scalar context, only the filehandle is returned and the
file will automatically be deleted when closed on operating systems
that support this (see the description of tmpfile() elsewhere in this
document).  This is the preferred mode of operation, as if you only
have a filehandle, you can never create a race condition by fumbling
with the filename. On systems that can not unlink an open file or can
not mark a file as temporary when it is opened (for example, Windows
NT uses the C<O_TEMPORARY> flag) the file is marked for deletion when
the program ends (equivalent to setting UNLINK to 1). The C<UNLINK>
flag is ignored if present.

  (undef, $filename) = tempfile($template, OPEN => 0);

This will return the filename based on the template but
will not open this file.  Cannot be used in conjunction with
UNLINK set to true. Default is to always open the file
to protect from possible race conditions. A warning is issued
if warnings are turned on. Consider using the tmpnam()
and mktemp() functions described elsewhere in this document
if opening the file is not required.

If the operating system supports it (for example BSD derived systems), the 
filehandle will be opened with O_EXLOCK (open with exclusive file lock). 
This can sometimes cause problems if the intention is to pass the filename 
to another system that expects to take an exclusive lock itself (such as 
DBD::SQLite) whilst ensuring that the tempfile is not reused. In this 
situation the "EXLOCK" option can be passed to tempfile. By default EXLOCK 
will be true (this retains compatibility with earlier releases).

  ($fh, $filename) = tempfile($template, EXLOCK => 0);

Options can be combined as required.

Will croak() if there is an error.

=cut

sub tempfile {
  if ( @_ && $_[0] eq 'File::Temp' ) {
      croak "'tempfile' can't be called as a method";
  }
  # Can not check for argument count since we can have any
  # number of args

  # Default options
  my %options = (
                 "DIR"    => undef, # Directory prefix
                 "SUFFIX" => '',    # Template suffix
                 "UNLINK" => 0,     # Do not unlink file on exit
                 "OPEN"   => 1,     # Open file
                 "TMPDIR" => 0, # Place tempfile in tempdir if template specified
                 "EXLOCK" => 1, # Open file with O_EXLOCK
                );

  # Check to see whether we have an odd or even number of arguments
  my ($maybe_template, $args) = _parse_args(@_);
  my $template = @$maybe_template ? $maybe_template->[0] : undef;

  # Read the options and merge with defaults
  %options = (%options, %$args);

  # First decision is whether or not to open the file
  if (! $options{"OPEN"}) {

    warn "tempfile(): temporary filename requested but not opened.\nPossibly unsafe, consider using tempfile() with OPEN set to true\n"
      if $^W;

  }

  if ($options{"DIR"} and $^O eq 'VMS') {

    # on VMS turn []foo into [.foo] for concatenation
    $options{"DIR"} = VMS::Filespec::vmspath($options{"DIR"});
  }

  # Construct the template

  # Have a choice of trying to work around the mkstemp/mktemp/tmpnam etc
  # functions or simply constructing a template and using _gettemp()
  # explicitly. Go for the latter

  # First generate a template if not defined and prefix the directory
  # If no template must prefix the temp directory
  if (defined $template) {
    # End up with current directory if neither DIR not TMPDIR are set
    if ($options{"DIR"}) {

      $template = File::Spec->catfile($options{"DIR"}, $template);

    } elsif ($options{TMPDIR}) {

      $template = File::Spec->catfile(File::Spec->tmpdir, $template );

    }

  } else {

    if ($options{"DIR"}) {

      $template = File::Spec->catfile($options{"DIR"}, TEMPXXX);

    } else {

      $template = File::Spec->catfile(File::Spec->tmpdir, TEMPXXX);

    }

  }

  # Now add a suffix
  $template .= $options{"SUFFIX"};

  # Determine whether we should tell _gettemp to unlink the file
  # On unix this is irrelevant and can be worked out after the file is
  # opened (simply by unlinking the open filehandle). On Windows or VMS
  # we have to indicate temporary-ness when we open the file. In general
  # we only want a true temporary file if we are returning just the
  # filehandle - if the user wants the filename they probably do not
  # want the file to disappear as soon as they close it (which may be
  # important if they want a child process to use the file)
  # For this reason, tie unlink_on_close to the return context regardless
  # of OS.
  my $unlink_on_close = ( wantarray ? 0 : 1);

  # Create the file
  my ($fh, $path, $errstr);
  croak "Error in tempfile() using template $template: $errstr"
    unless (($fh, $path) = _gettemp($template,
                                    "open" => $options{'OPEN'},
                                    "mkdir"=> 0 ,
                                    "unlink_on_close" => $unlink_on_close,
                                    "suffixlen" => length($options{'SUFFIX'}),
                                    "ErrStr" => \$errstr,
                                    "use_exlock" => $options{EXLOCK},
                                   ) );

  # Set up an exit handler that can do whatever is right for the
  # system. This removes files at exit when requested explicitly or when
  # system is asked to unlink_on_close but is unable to do so because
  # of OS limitations.
  # The latter should be achieved by using a tied filehandle.
  # Do not check return status since this is all done with END blocks.
  _deferred_unlink($fh, $path, 0) if $options{"UNLINK"};

  # Return
  if (wantarray()) {

    if ($options{'OPEN'}) {
      return ($fh, $path);
    } else {
      return (undef, $path);
    }

  } else {

    # Unlink the file. It is up to unlink0 to decide what to do with
    # this (whether to unlink now or to defer until later)
    unlink0($fh, $path) or croak "Error unlinking file $path using unlink0";

    # Return just the filehandle.
    return $fh;
  }


}

=item B<tempdir>

This is the recommended interface for creation of temporary
directories.  By default the directory will not be removed on exit
(that is, it won't be temporary; this behaviour can not be changed
because of issues with backwards compatibility). To enable removal
either use the CLEANUP option which will trigger removal on program
exit, or consider using the "newdir" method in the object interface which
will allow the directory to be cleaned up when the object goes out of
scope.

The behaviour of the function depends on the arguments:

  $tempdir = tempdir();

Create a directory in tmpdir() (see L<File::Spec|File::Spec>).

  $tempdir = tempdir( $template );

Create a directory from the supplied template. This template is
similar to that described for tempfile(). `X' characters at the end
of the template are replaced with random letters to construct the
directory name. At least four `X' characters must be in the template.

  $tempdir = tempdir ( DIR => $dir );

Specifies the directory to use for the temporary directory.
The temporary directory name is derived from an internal template.

  $tempdir = tempdir ( $template, DIR => $dir );

Prepend the supplied directory name to the template. The template
should not include parent directory specifications itself. Any parent
directory specifications are removed from the template before
prepending the supplied directory.

  $tempdir = tempdir ( $template, TMPDIR => 1 );

Using the supplied template, create the temporary directory in
a standard location for temporary files. Equivalent to doing

  $tempdir = tempdir ( $template, DIR => File::Spec->tmpdir);

but shorter. Parent directory specifications are stripped from the
template itself. The C<TMPDIR> option is ignored if C<DIR> is set
explicitly.  Additionally, C<TMPDIR> is implied if neither a template
nor a directory are supplied.

  $tempdir = tempdir( $template, CLEANUP => 1);

Create a temporary directory using the supplied template, but
attempt to remove it (and all files inside it) when the program
exits. Note that an attempt will be made to remove all files from
the directory even if they were not created by this module (otherwise
why ask to clean it up?). The directory removal is made with
the rmtree() function from the L<File::Path|File::Path> module.
Of course, if the template is not specified, the temporary directory
will be created in tmpdir() and will also be removed at program exit.

Will croak() if there is an error.

=cut

# '

sub tempdir  {
  if ( @_ && $_[0] eq 'File::Temp' ) {
      croak "'tempdir' can't be called as a method";
  }

  # Can not check for argument count since we can have any
  # number of args

  # Default options
  my %options = (
                 "CLEANUP"    => 0, # Remove directory on exit
                 "DIR"        => '', # Root directory
                 "TMPDIR"     => 0,  # Use tempdir with template
                );

  # Check to see whether we have an odd or even number of arguments
  my ($maybe_template, $args) = _parse_args(@_);
  my $template = @$maybe_template ? $maybe_template->[0] : undef;

  # Read the options and merge with defaults
  %options = (%options, %$args);

  # Modify or generate the template

  # Deal with the DIR and TMPDIR options
  if (defined $template) {

    # Need to strip directory path if using DIR or TMPDIR
    if ($options{'TMPDIR'} || $options{'DIR'}) {

      # Strip parent directory from the filename
      #
      # There is no filename at the end
      $template = VMS::Filespec::vmspath($template) if $^O eq 'VMS';
      my ($volume, $directories, undef) = File::Spec->splitpath( $template, 1);

      # Last directory is then our template
      $template = (File::Spec->splitdir($directories))[-1];

      # Prepend the supplied directory or temp dir
      if ($options{"DIR"}) {

        $template = File::Spec->catdir($options{"DIR"}, $template);

      } elsif ($options{TMPDIR}) {

        # Prepend tmpdir
        $template = File::Spec->catdir(File::Spec->tmpdir, $template);

      }

    }

  } else {

    if ($options{"DIR"}) {

      $template = File::Spec->catdir($options{"DIR"}, TEMPXXX);

    } else {

      $template = File::Spec->catdir(File::Spec->tmpdir, TEMPXXX);

    }

  }

  # Create the directory
  my $tempdir;
  my $suffixlen = 0;
  if ($^O eq 'VMS') {           # dir names can end in delimiters
    $template =~ m/([\.\]:>]+)$/;
    $suffixlen = length($1);
  }
  if ( ($^O eq 'MacOS') && (substr($template, -1) eq ':') ) {
    # dir name has a trailing ':'
    ++$suffixlen;
  }

  my $errstr;
  croak "Error in tempdir() using $template: $errstr"
    unless ((undef, $tempdir) = _gettemp($template,
                                         "open" => 0,
                                         "mkdir"=> 1 ,
                                         "suffixlen" => $suffixlen,
                                         "ErrStr" => \$errstr,
                                        ) );

  # Install exit handler; must be dynamic to get lexical
  if ( $options{'CLEANUP'} && -d $tempdir) {
    _deferred_unlink(undef, $tempdir, 1);
  }

  # Return the dir name
  return $tempdir;

}

=back

=head1 MKTEMP FUNCTIONS

The following functions are Perl implementations of the
mktemp() family of temp file generation system calls.

=over 4

=item B<mkstemp>

Given a template, returns a filehandle to the temporary file and the name
of the file.

  ($fh, $name) = mkstemp( $template );

In scalar context, just the filehandle is returned.

The template may be any filename with some number of X's appended
to it, for example F</tmp/temp.XXXX>. The trailing X's are replaced
with unique alphanumeric combinations.

Will croak() if there is an error.

=cut



sub mkstemp {

  croak "Usage: mkstemp(template)"
    if scalar(@_) != 1;

  my $template = shift;

  my ($fh, $path, $errstr);
  croak "Error in mkstemp using $template: $errstr"
    unless (($fh, $path) = _gettemp($template,
                                    "open" => 1,
                                    "mkdir"=> 0 ,
                                    "suffixlen" => 0,
                                    "ErrStr" => \$errstr,
                                   ) );

  if (wantarray()) {
    return ($fh, $path);
  } else {
    return $fh;
  }

}


=item B<mkstemps>

Similar to mkstemp(), except that an extra argument can be supplied
with a suffix to be appended to the template.

  ($fh, $name) = mkstemps( $template, $suffix );

For example a template of C<testXXXXXX> and suffix of C<.dat>
would generate a file similar to F<testhGji_w.dat>.

Returns just the filehandle alone when called in scalar context.

Will croak() if there is an error.

=cut

sub mkstemps {

  croak "Usage: mkstemps(template, suffix)"
    if scalar(@_) != 2;


  my $template = shift;
  my $suffix   = shift;

  $template .= $suffix;

  my ($fh, $path, $errstr);
  croak "Error in mkstemps using $template: $errstr"
    unless (($fh, $path) = _gettemp($template,
                                    "open" => 1,
                                    "mkdir"=> 0 ,
                                    "suffixlen" => length($suffix),
                                    "ErrStr" => \$errstr,
                                   ) );

  if (wantarray()) {
    return ($fh, $path);
  } else {
    return $fh;
  }

}

=item B<mkdtemp>

Create a directory from a template. The template must end in
X's that are replaced by the routine.

  $tmpdir_name = mkdtemp($template);

Returns the name of the temporary directory created.

Directory must be removed by the caller.

Will croak() if there is an error.

=cut

#' # for emacs

sub mkdtemp {

  croak "Usage: mkdtemp(template)"
    if scalar(@_) != 1;

  my $template = shift;
  my $suffixlen = 0;
  if ($^O eq 'VMS') {           # dir names can end in delimiters
    $template =~ m/([\.\]:>]+)$/;
    $suffixlen = length($1);
  }
  if ( ($^O eq 'MacOS') && (substr($template, -1) eq ':') ) {
    # dir name has a trailing ':'
    ++$suffixlen;
  }
  my ($junk, $tmpdir, $errstr);
  croak "Error creating temp directory from template $template\: $errstr"
    unless (($junk, $tmpdir) = _gettemp($template,
                                        "open" => 0,
                                        "mkdir"=> 1 ,
                                        "suffixlen" => $suffixlen,
                                        "ErrStr" => \$errstr,
                                       ) );

  return $tmpdir;

}

=item B<mktemp>

Returns a valid temporary filename but does not guarantee
that the file will not be opened by someone else.

  $unopened_file = mktemp($template);

Template is the same as that required by mkstemp().

Will croak() if there is an error.

=cut

sub mktemp {

  croak "Usage: mktemp(template)"
    if scalar(@_) != 1;

  my $template = shift;

  my ($tmpname, $junk, $errstr);
  croak "Error getting name to temp file from template $template: $errstr"
    unless (($junk, $tmpname) = _gettemp($template,
                                         "open" => 0,
                                         "mkdir"=> 0 ,
                                         "suffixlen" => 0,
                                         "ErrStr" => \$errstr,
                                        ) );

  return $tmpname;
}

=back

=head1 POSIX FUNCTIONS

This section describes the re-implementation of the tmpnam()
and tmpfile() functions described in L<POSIX>
using the mkstemp() from this module.

Unlike the L<POSIX|POSIX> implementations, the directory used
for the temporary file is not specified in a system include
file (C<P_tmpdir>) but simply depends on the choice of tmpdir()
returned by L<File::Spec|File::Spec>. On some implementations this
location can be set using the C<TMPDIR> environment variable, which
may not be secure.
If this is a problem, simply use mkstemp() and specify a template.

=over 4

=item B<tmpnam>

When called in scalar context, returns the full name (including path)
of a temporary file (uses mktemp()). The only check is that the file does
not already exist, but there is no guarantee that that condition will
continue to apply.

  $file = tmpnam();

When called in list context, a filehandle to the open file and
a filename are returned. This is achieved by calling mkstemp()
after constructing a suitable template.

  ($fh, $file) = tmpnam();

If possible, this form should be used to prevent possible
race conditions.

See L<File::Spec/tmpdir> for information on the choice of temporary
directory for a particular operating system.

Will croak() if there is an error.

=cut

sub tmpnam {

  # Retrieve the temporary directory name
  my $tmpdir = File::Spec->tmpdir;

  croak "Error temporary directory is not writable"
    if $tmpdir eq '';

  # Use a ten character template and append to tmpdir
  my $template = File::Spec->catfile($tmpdir, TEMPXXX);

  if (wantarray() ) {
    return mkstemp($template);
  } else {
    return mktemp($template);
  }

}

=item B<tmpfile>

Returns the filehandle of a temporary file.

  $fh = tmpfile();

The file is removed when the filehandle is closed or when the program
exits. No access to the filename is provided.

If the temporary file can not be created undef is returned.
Currently this command will probably not work when the temporary
directory is on an NFS file system.

Will croak() if there is an error.

=cut

sub tmpfile {

  # Simply call tmpnam() in a list context
  my ($fh, $file) = tmpnam();

  # Make sure file is removed when filehandle is closed
  # This will fail on NFS
  unlink0($fh, $file)
    or return undef;

  return $fh;

}

=back

=head1 ADDITIONAL FUNCTIONS

These functions are provided for backwards compatibility
with common tempfile generation C library functions.

They are not exported and must be addressed using the full package
name.

=over 4

=item B<tempnam>

Return the name of a temporary file in the specified directory
using a prefix. The file is guaranteed not to exist at the time
the function was called, but such guarantees are good for one
clock tick only.  Always use the proper form of C<sysopen>
with C<O_CREAT | O_EXCL> if you must open such a filename.

  $filename = File::Temp::tempnam( $dir, $prefix );

Equivalent to running mktemp() with $dir/$prefixXXXXXXXX
(using unix file convention as an example)

Because this function uses mktemp(), it can suffer from race conditions.

Will croak() if there is an error.

=cut

sub tempnam {

  croak 'Usage tempnam($dir, $prefix)' unless scalar(@_) == 2;

  my ($dir, $prefix) = @_;

  # Add a string to the prefix
  $prefix .= 'XXXXXXXX';

  # Concatenate the directory to the file
  my $template = File::Spec->catfile($dir, $prefix);

  return mktemp($template);

}

=back

=head1 UTILITY FUNCTIONS

Useful functions for dealing with the filehandle and filename.

=over 4

=item B<unlink0>

Given an open filehandle and the associated filename, make a safe
unlink. This is achieved by first checking that the filename and
filehandle initially point to the same file and that the number of
links to the file is 1 (all fields returned by stat() are compared).
Then the filename is unlinked and the filehandle checked once again to
verify that the number of links on that file is now 0.  This is the
closest you can come to making sure that the filename unlinked was the
same as the file whose descriptor you hold.

  unlink0($fh, $path)
     or die "Error unlinking file $path safely";

Returns false on error but croaks() if there is a security
anomaly. The filehandle is not closed since on some occasions this is
not required.

On some platforms, for example Windows NT, it is not possible to
unlink an open file (the file must be closed first). On those
platforms, the actual unlinking is deferred until the program ends and
good status is returned. A check is still performed to make sure that
the filehandle and filename are pointing to the same thing (but not at
the time the end block is executed since the deferred removal may not
have access to the filehandle).

Additionally, on Windows NT not all the fields returned by stat() can
be compared. For example, the C<dev> and C<rdev> fields seem to be
different.  Also, it seems that the size of the file returned by stat()
does not always agree, with C<stat(FH)> being more accurate than
C<stat(filename)>, presumably because of caching issues even when
using autoflush (this is usually overcome by waiting a while after
writing to the tempfile before attempting to C<unlink0> it).

Finally, on NFS file systems the link count of the file handle does
not always go to zero immediately after unlinking. Currently, this
command is expected to fail on NFS disks.

This function is disabled if the global variable $KEEP_ALL is true
and an unlink on open file is supported. If the unlink is to be deferred
to the END block, the file is still registered for removal.

This function should not be called if you are using the object oriented
interface since the it will interfere with the object destructor deleting
the file.

=cut

sub unlink0 {

  croak 'Usage: unlink0(filehandle, filename)'
    unless scalar(@_) == 2;

  # Read args
  my ($fh, $path) = @_;

  cmpstat($fh, $path) or return 0;

  # attempt remove the file (does not work on some platforms)
  if (_can_unlink_opened_file()) {

    # return early (Without unlink) if we have been instructed to retain files.
    return 1 if $KEEP_ALL;

    # XXX: do *not* call this on a directory; possible race
    #      resulting in recursive removal
    croak "unlink0: $path has become a directory!" if -d $path;
    unlink($path) or return 0;

    # Stat the filehandle
    my @fh = stat $fh;

    print "Link count = $fh[3] \n" if $DEBUG;

    # Make sure that the link count is zero
    # - Cygwin provides deferred unlinking, however,
    #   on Win9x the link count remains 1
    # On NFS the link count may still be 1 but we can't know that
    # we are on NFS.  Since we can't be sure, we'll defer it

    return 1 if $fh[3] == 0 || $^O eq 'cygwin';
  }
  # fall-through if we can't unlink now
  _deferred_unlink($fh, $path, 0);
  return 1;
}

=item B<cmpstat>

Compare C<stat> of filehandle with C<stat> of provided filename.  This
can be used to check that the filename and filehandle initially point
to the same file and that the number of links to the file is 1 (all
fields returned by stat() are compared).

  cmpstat($fh, $path)
     or die "Error comparing handle with file";

Returns false if the stat information differs or if the link count is
greater than 1. Calls croak if there is a security anomaly.

On certain platforms, for example Windows, not all the fields returned by stat()
can be compared. For example, the C<dev> and C<rdev> fields seem to be
different in Windows.  Also, it seems that the size of the file
returned by stat() does not always agree, with C<stat(FH)> being more
accurate than C<stat(filename)>, presumably because of caching issues
even when using autoflush (this is usually overcome by waiting a while
after writing to the tempfile before attempting to C<unlink0> it).

Not exported by default.

=cut

sub cmpstat {

  croak 'Usage: cmpstat(filehandle, filename)'
    unless scalar(@_) == 2;

  # Read args
  my ($fh, $path) = @_;

  warn "Comparing stat\n"
    if $DEBUG;

  # Stat the filehandle - which may be closed if someone has manually
  # closed the file. Can not turn off warnings without using $^W
  # unless we upgrade to 5.006 minimum requirement
  my @fh;
  {
    local ($^W) = 0;
    @fh = stat $fh;
  }
  return unless @fh;

  if ($fh[3] > 1 && $^W) {
    carp "unlink0: fstat found too many links; SB=@fh" if $^W;
  }

  # Stat the path
  my @path = stat $path;

  unless (@path) {
    carp "unlink0: $path is gone already" if $^W;
    return;
  }

  # this is no longer a file, but may be a directory, or worse
  unless (-f $path) {
    confess "panic: $path is no longer a file: SB=@fh";
  }

  # Do comparison of each member of the array
  # On WinNT dev and rdev seem to be different
  # depending on whether it is a file or a handle.
  # Cannot simply compare all members of the stat return
  # Select the ones we can use
  my @okstat = (0..$#fh);       # Use all by default
  if ($^O eq 'MSWin32') {
    @okstat = (1,2,3,4,5,7,8,9,10);
  } elsif ($^O eq 'os2') {
    @okstat = (0, 2..$#fh);
  } elsif ($^O eq 'VMS') {      # device and file ID are sufficient
    @okstat = (0, 1);
  } elsif ($^O eq 'dos') {
    @okstat = (0,2..7,11..$#fh);
  } elsif ($^O eq 'mpeix') {
    @okstat = (0..4,8..10);
  }

  # Now compare each entry explicitly by number
  for (@okstat) {
    print "Comparing: $_ : $fh[$_] and $path[$_]\n" if $DEBUG;
    # Use eq rather than == since rdev, blksize, and blocks (6, 11,
    # and 12) will be '' on platforms that do not support them.  This
    # is fine since we are only comparing integers.
    unless ($fh[$_] eq $path[$_]) {
      warn "Did not match $_ element of stat\n" if $DEBUG;
      return 0;
    }
  }

  return 1;
}

=item B<unlink1>

Similar to C<unlink0> except after file comparison using cmpstat, the
filehandle is closed prior to attempting to unlink the file. This
allows the file to be removed without using an END block, but does
mean that the post-unlink comparison of the filehandle state provided
by C<unlink0> is not available.

  unlink1($fh, $path)
     or die "Error closing and unlinking file";

Usually called from the object destructor when using the OO interface.

Not exported by default.

This function is disabled if the global variable $KEEP_ALL is true.

Can call croak() if there is a security anomaly during the stat()
comparison.

=cut

sub unlink1 {
  croak 'Usage: unlink1(filehandle, filename)'
    unless scalar(@_) == 2;

  # Read args
  my ($fh, $path) = @_;

  cmpstat($fh, $path) or return 0;

  # Close the file
  close( $fh ) or return 0;

  # Make sure the file is writable (for windows)
  _force_writable( $path );

  # return early (without unlink) if we have been instructed to retain files.
  return 1 if $KEEP_ALL;

  # remove the file
  return unlink($path);
}

=item B<cleanup>

Calling this function will cause any temp files or temp directories
that are registered for removal to be removed. This happens automatically
when the process exits but can be triggered manually if the caller is sure
that none of the temp files are required. This method can be registered as
an Apache callback.

Note that if a temp directory is your current directory, it cannot be
removed.  C<chdir()> out of the directory first before calling
C<cleanup()>. (For the cleanup at program exit when the CLEANUP flag
is set, this happens automatically.)

On OSes where temp files are automatically removed when the temp file
is closed, calling this function will have no effect other than to remove
temporary directories (which may include temporary files).

  File::Temp::cleanup();

Not exported by default.

=back

=head1 PACKAGE VARIABLES

These functions control the global state of the package.

=over 4

=item B<safe_level>

Controls the lengths to which the module will go to check the safety of the
temporary file or directory before proceeding.
Options are:

=over 8

=item STANDARD

Do the basic security measures to ensure the directory exists and is
writable, that temporary files are opened only if they do not already
exist, and that possible race conditions are avoided.  Finally the
L<unlink0|"unlink0"> function is used to remove files safely.

=item MEDIUM

In addition to the STANDARD security, the output directory is checked
to make sure that it is owned either by root or the user running the
program. If the directory is writable by group or by other, it is then
checked to make sure that the sticky bit is set.

Will not work on platforms that do not support the C<-k> test
for sticky bit.

=item HIGH

In addition to the MEDIUM security checks, also check for the
possibility of ``chown() giveaway'' using the L<POSIX|POSIX>
sysconf() function. If this is a possibility, each directory in the
path is checked in turn for safeness, recursively walking back to the
root directory.

For platforms that do not support the L<POSIX|POSIX>
C<_PC_CHOWN_RESTRICTED> symbol (for example, Windows NT) it is
assumed that ``chown() giveaway'' is possible and the recursive test
is performed.

=back

The level can be changed as follows:

  File::Temp->safe_level( File::Temp::HIGH );

The level constants are not exported by the module.

Currently, you must be running at least perl v5.6.0 in order to
run with MEDIUM or HIGH security. This is simply because the
safety tests use functions from L<Fcntl|Fcntl> that are not
available in older versions of perl. The problem is that the version
number for Fcntl is the same in perl 5.6.0 and in 5.005_03 even though
they are different versions.

On systems that do not support the HIGH or MEDIUM safety levels
(for example Win NT or OS/2) any attempt to change the level will
be ignored. The decision to ignore rather than raise an exception
allows portable programs to be written with high security in mind
for the systems that can support this without those programs failing
on systems where the extra tests are irrelevant.

If you really need to see whether the change has been accepted
simply examine the return value of C<safe_level>.

  $newlevel = File::Temp->safe_level( File::Temp::HIGH );
  die "Could not change to high security"
      if $newlevel != File::Temp::HIGH;

=cut

{
  # protect from using the variable itself
  my $LEVEL = STANDARD;
  sub safe_level {
    my $self = shift;
    if (@_) {
      my $level = shift;
      if (($level != STANDARD) && ($level != MEDIUM) && ($level != HIGH)) {
        carp "safe_level: Specified level ($level) not STANDARD, MEDIUM or HIGH - ignoring\n" if $^W;
      } else {
        # Don't allow this on perl 5.005 or earlier
        if ($] < 5.006 && $level != STANDARD) {
          # Cant do MEDIUM or HIGH checks
          croak "Currently requires perl 5.006 or newer to do the safe checks";
        }
        # Check that we are allowed to change level
        # Silently ignore if we can not.
        $LEVEL = $level if _can_do_level($level);
      }
    }
    return $LEVEL;
  }
}

=item TopSystemUID

This is the highest UID on the current system that refers to a root
UID. This is used to make sure that the temporary directory is
owned by a system UID (C<root>, C<bin>, C<sys> etc) rather than
simply by root.

This is required since on many unix systems C</tmp> is not owned
by root.

Default is to assume that any UID less than or equal to 10 is a root
UID.

  File::Temp->top_system_uid(10);
  my $topid = File::Temp->top_system_uid;

This value can be adjusted to reduce security checking if required.
The value is only relevant when C<safe_level> is set to MEDIUM or higher.

=cut

{
  my $TopSystemUID = 10;
  $TopSystemUID = 197108 if $^O eq 'interix'; # "Administrator"
  sub top_system_uid {
    my $self = shift;
    if (@_) {
      my $newuid = shift;
      croak "top_system_uid: UIDs should be numeric"
        unless $newuid =~ /^\d+$/s;
      $TopSystemUID = $newuid;
    }
    return $TopSystemUID;
  }
}

=item B<$KEEP_ALL>

Controls whether temporary files and directories should be retained
regardless of any instructions in the program to remove them
automatically.  This is useful for debugging but should not be used in
production code.

  $File::Temp::KEEP_ALL = 1;

Default is for files to be removed as requested by the caller.

In some cases, files will only be retained if this variable is true
when the file is created. This means that you can not create a temporary
file, set this variable and expect the temp file to still be around
when the program exits.

=item B<$DEBUG>

Controls whether debugging messages should be enabled.

  $File::Temp::DEBUG = 1;

Default is for debugging mode to be disabled.

=back

=head1 WARNING

For maximum security, endeavour always to avoid ever looking at,
touching, or even imputing the existence of the filename.  You do not
know that that filename is connected to the same file as the handle
you have, and attempts to check this can only trigger more race
conditions.  It's far more secure to use the filehandle alone and
dispense with the filename altogether.

If you need to pass the handle to something that expects a filename
then on a unix system you can use C<"/dev/fd/" . fileno($fh)> for
arbitrary programs. Perl code that uses the 2-argument version of
C<< open >> can be passed C<< "+<=&" . fileno($fh) >>. Otherwise you
will need to pass the filename. You will have to clear the
close-on-exec bit on that file descriptor before passing it to another
process.

    use Fcntl qw/F_SETFD F_GETFD/;
    fcntl($tmpfh, F_SETFD, 0)
        or die "Can't clear close-on-exec flag on temp fh: $!\n";

=head2 Temporary files and NFS

Some problems are associated with using temporary files that reside
on NFS file systems and it is recommended that a local filesystem
is used whenever possible. Some of the security tests will most probably
fail when the temp file is not local. Additionally, be aware that
the performance of I/O operations over NFS will not be as good as for
a local disk.

=head2 Forking

In some cases files created by File::Temp are removed from within an
END block. Since END blocks are triggered when a child process exits
(unless C<POSIX::_exit()> is used by the child) File::Temp takes care
to only remove those temp files created by a particular process ID. This
means that a child will not attempt to remove temp files created by the
parent process.

If you are forking many processes in parallel that are all creating
temporary files, you may need to reset the random number seed using
srand(EXPR) in each child else all the children will attempt to walk
through the same set of random file names and may well cause
themselves to give up if they exceed the number of retry attempts.

=head2 Directory removal

Note that if you have chdir'ed into the temporary directory and it is
subsequently cleaned up (either in the END block or as part of object
destruction), then you will get a warning from File::Path::rmtree().

=head2 Taint mode

If you need to run code under taint mode, updating to the latest
L<File::Spec> is highly recommended.

=head2 BINMODE

The file returned by File::Temp will have been opened in binary mode
if such a mode is available. If that is not correct, use the C<binmode()>
function to change the mode of the filehandle.

Note that you can modify the encoding of a file opened by File::Temp
also by using C<binmode()>.

=head1 HISTORY

Originally began life in May 1999 as an XS interface to the system
mkstemp() function. In March 2000, the OpenBSD mkstemp() code was
translated to Perl for total control of the code's
security checking, to ensure the presence of the function regardless of
operating system and to help with portability. The module was shipped
as a standard part of perl from v5.6.1.

=head1 SEE ALSO

L<POSIX/tmpnam>, L<POSIX/tmpfile>, L<File::Spec>, L<File::Path>

See L<IO::File> and L<File::MkTemp>, L<Apache::TempFile> for
different implementations of temporary file handling.

See L<File::Tempdir> for an alternative object-oriented wrapper for
the C<tempdir> function.

=head1 AUTHOR

Tim Jenness E<lt>tjenness@cpan.orgE<gt>

Copyright (C) 2007-2010 Tim Jenness.
Copyright (C) 1999-2007 Tim Jenness and the UK Particle Physics and
Astronomy Research Council. All Rights Reserved.  This program is free
software; you can redistribute it and/or modify it under the same
terms as Perl itself.

Original Perl implementation loosely based on the OpenBSD C code for
mkstemp(). Thanks to Tom Christiansen for suggesting that this module
should be written and providing ideas for code improvements and
security enhancements.

=cut

package File::Temp::Dir;

use File::Path qw/ rmtree /;
use strict;
use overload '""' => "STRINGIFY",
  '0+' => \&File::Temp::NUMIFY,
  fallback => 1;

# private class specifically to support tempdir objects
# created by File::Temp->newdir

# ostensibly the same method interface as File::Temp but without
# inheriting all the IO::Seekable methods and other cruft

# Read-only - returns the name of the temp directory

sub dirname {
  my $self = shift;
  return $self->{DIRNAME};
}

sub STRINGIFY {
  my $self = shift;
  return $self->dirname;
}

sub unlink_on_destroy {
  my $self = shift;
  if (@_) {
    $self->{CLEANUP} = shift;
  }
  return $self->{CLEANUP};
}

sub DESTROY {
  my $self = shift;
  local($., $@, $!, $^E, $?);
  if ($self->unlink_on_destroy && 
      $$ == $self->{LAUNCHPID} && !$File::Temp::KEEP_ALL) {
    if (-d $self->{REALNAME}) {
      # Some versions of rmtree will abort if you attempt to remove
      # the directory you are sitting in. We protect that and turn it
      # into a warning. We do this because this occurs during object
      # destruction and so can not be caught by the user.
      eval { rmtree($self->{REALNAME}, $File::Temp::DEBUG, 0); };
      warn $@ if ($@ && $^W);
    }
  }
}


1;

# vim: ts=2 sts=2 sw=2 et: