summaryrefslogtreecommitdiff
path: root/ShellPkg/Library/UefiShellLib/UefiShellLib.c
blob: 020d6c560d435da186ba98afac02197f2c775c38 (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
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
/** @file
  Provides interface to shell functionality for shell commands and applications.

Copyright (c) 2006 - 2009, Intel Corporation<BR>
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution.  The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include <Uefi.h>
#include <Library/ShellLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/BaseLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/DevicePathLib.h>
#include <Library/PcdLib.h>
#include <Library/FileHandleLib.h>
#include <Library/PrintLib.h>
#include <Library/UefiLib.h>
#include <Library/HiiLib.h>

#include <Protocol/EfiShellEnvironment2.h>
#include <Protocol/EfiShellInterface.h>
#include <Protocol/EfiShell.h>
#include <Protocol/EfiShellParameters.h>
#include <Protocol/SimpleFileSystem.h>

#include "UefiShellLib.h"

#define MAX_FILE_NAME_LEN 522 // (20 * (6+5+2))+1) unicode characters from EFI FAT spec (doubled for bytes)
#define FIND_XXXXX_FILE_BUFFER_SIZE (SIZE_OF_EFI_FILE_INFO + MAX_FILE_NAME_LEN)

//
// This is not static since it's extern in the .h file
//
SHELL_PARAM_ITEM EmptyParamList[] = {
  {NULL, TypeMax}
  };

//
// Static file globals for the shell library
//
STATIC EFI_SHELL_ENVIRONMENT2        *mEfiShellEnvironment2;
STATIC EFI_SHELL_INTERFACE           *mEfiShellInterface;
STATIC EFI_SHELL_PROTOCOL            *mEfiShellProtocol;
STATIC EFI_SHELL_PARAMETERS_PROTOCOL *mEfiShellParametersProtocol;
STATIC EFI_HANDLE                    mEfiShellEnvironment2Handle;
STATIC FILE_HANDLE_FUNCTION_MAP      FileFunctionMap;
STATIC UINTN                         mTotalParameterCount;

/**
  Check if a Unicode character is a hexadecimal character.

  This internal function checks if a Unicode character is a 
  decimal character.  The valid hexadecimal character is 
  L'0' to L'9', L'a' to L'f', or L'A' to L'F'.


  @param  Char  The character to check against.

  @retval TRUE  If the Char is a hexadecmial character.
  @retval FALSE If the Char is not a hexadecmial character.

**/
BOOLEAN
EFIAPI
ShellInternalIsHexaDecimalDigitCharacter (
  IN      CHAR16                    Char
  ) {
  return (BOOLEAN) ((Char >= L'0' && Char <= L'9') || (Char >= L'A' && Char <= L'F') || (Char >= L'a' && Char <= L'f'));
}

/**
  helper function to find ShellEnvironment2 for constructor
**/
EFI_STATUS
EFIAPI
ShellFindSE2 (
  IN EFI_HANDLE        ImageHandle
  ) {
  EFI_STATUS  Status;
  EFI_HANDLE  *Buffer;
  UINTN       BufferSize;
  UINTN       HandleIndex;

  BufferSize = 0;
  Buffer = NULL;
  Status = gBS->OpenProtocol(ImageHandle, 
                             &gEfiShellEnvironment2Guid,
                             (VOID **)&mEfiShellEnvironment2,
                             ImageHandle,
                             NULL,
                             EFI_OPEN_PROTOCOL_GET_PROTOCOL
                             );
  //
  // look for the mEfiShellEnvironment2 protocol at a higher level
  //
  if (EFI_ERROR (Status) || !(CompareGuid (&mEfiShellEnvironment2->SESGuid, &gEfiShellEnvironment2ExtGuid) != FALSE)){
    //
    // figure out how big of a buffer we need.
    //
    Status = gBS->LocateHandle (ByProtocol,
                                &gEfiShellEnvironment2Guid,
                                NULL, // ignored for ByProtocol
                                &BufferSize,
                                Buffer
                                );
    //
    // maybe it's not there???
    //
    if (Status == EFI_BUFFER_TOO_SMALL) {
      Buffer = (EFI_HANDLE*)AllocatePool(BufferSize);
      ASSERT(Buffer != NULL);
      Status = gBS->LocateHandle (ByProtocol,
                                  &gEfiShellEnvironment2Guid,
                                  NULL, // ignored for ByProtocol
                                  &BufferSize,
                                  Buffer
                                  );
    }
    if (!EFI_ERROR (Status)) {
      //
      // now parse the list of returned handles
      //
      Status = EFI_NOT_FOUND;
      for (HandleIndex = 0; HandleIndex < (BufferSize/sizeof(Buffer[0])); HandleIndex++) {
        Status = gBS->OpenProtocol(Buffer[HandleIndex], 
                                   &gEfiShellEnvironment2Guid,
                                   (VOID **)&mEfiShellEnvironment2,
                                   ImageHandle,
                                   NULL,
                                   EFI_OPEN_PROTOCOL_GET_PROTOCOL
                                   );
         if (CompareGuid (&mEfiShellEnvironment2->SESGuid, &gEfiShellEnvironment2ExtGuid) != FALSE) {
          mEfiShellEnvironment2Handle = Buffer[HandleIndex];
          Status = EFI_SUCCESS;
          break;
        }
      }
    }
  }
  if (Buffer != NULL) {
    FreePool (Buffer);
  }
  return (Status);
}

EFI_STATUS
EFIAPI
ShellLibConstructorWorker (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  ) {
  EFI_STATUS Status;

  //
  // Set the parameter count to an invalid number
  //
  mTotalParameterCount = (UINTN)(-1);

  //
  // UEFI 2.0 shell interfaces (used preferentially)
  //
  Status = gBS->OpenProtocol(ImageHandle, 
                             &gEfiShellProtocolGuid,
                             (VOID **)&mEfiShellProtocol,
                             ImageHandle,
                             NULL,
                             EFI_OPEN_PROTOCOL_GET_PROTOCOL
                             );
  if (EFI_ERROR(Status)) {
    mEfiShellProtocol = NULL;
  }
  Status = gBS->OpenProtocol(ImageHandle, 
                             &gEfiShellParametersProtocolGuid,
                             (VOID **)&mEfiShellParametersProtocol,
                             ImageHandle,
                             NULL,
                             EFI_OPEN_PROTOCOL_GET_PROTOCOL
                             );
  if (EFI_ERROR(Status)) {
    mEfiShellParametersProtocol = NULL;
  }

  if (mEfiShellParametersProtocol == NULL || mEfiShellProtocol == NULL) {
    //
    // Moved to seperate function due to complexity
    //
    Status = ShellFindSE2(ImageHandle);

    if (EFI_ERROR(Status)) {
      DEBUG((DEBUG_ERROR, "Status: 0x%08x\r\n", Status));
      mEfiShellEnvironment2 = NULL;
    }
    Status = gBS->OpenProtocol(ImageHandle, 
                               &gEfiShellInterfaceGuid,
                               (VOID **)&mEfiShellInterface,
                               ImageHandle,
                               NULL,
                               EFI_OPEN_PROTOCOL_GET_PROTOCOL
                               );
    if (EFI_ERROR(Status)) {
      mEfiShellInterface = NULL;
    }
  }
  //
  // only success getting 2 of either the old or new, but no 1/2 and 1/2
  //
  if ((mEfiShellEnvironment2 != NULL && mEfiShellInterface          != NULL) || 
      (mEfiShellProtocol     != NULL && mEfiShellParametersProtocol != NULL)    ) {
    if (mEfiShellProtocol != NULL) {
      FileFunctionMap.GetFileInfo     = mEfiShellProtocol->GetFileInfo;
      FileFunctionMap.SetFileInfo     = mEfiShellProtocol->SetFileInfo;
      FileFunctionMap.ReadFile        = mEfiShellProtocol->ReadFile;
      FileFunctionMap.WriteFile       = mEfiShellProtocol->WriteFile;
      FileFunctionMap.CloseFile       = mEfiShellProtocol->CloseFile;
      FileFunctionMap.DeleteFile      = mEfiShellProtocol->DeleteFile;
      FileFunctionMap.GetFilePosition = mEfiShellProtocol->GetFilePosition;
      FileFunctionMap.SetFilePosition = mEfiShellProtocol->SetFilePosition;
      FileFunctionMap.FlushFile       = mEfiShellProtocol->FlushFile;
      FileFunctionMap.GetFileSize     = mEfiShellProtocol->GetFileSize;
    } else {
      FileFunctionMap.GetFileInfo     = FileHandleGetInfo;
      FileFunctionMap.SetFileInfo     = FileHandleSetInfo;
      FileFunctionMap.ReadFile        = FileHandleRead;
      FileFunctionMap.WriteFile       = FileHandleWrite;
      FileFunctionMap.CloseFile       = FileHandleClose;
      FileFunctionMap.DeleteFile      = FileHandleDelete;
      FileFunctionMap.GetFilePosition = FileHandleGetPosition;
      FileFunctionMap.SetFilePosition = FileHandleSetPosition;
      FileFunctionMap.FlushFile       = FileHandleFlush;
      FileFunctionMap.GetFileSize     = FileHandleGetSize;
    }
    return (EFI_SUCCESS);
  }
  return (EFI_NOT_FOUND);
}
/**
  Constructor for the Shell library.

  Initialize the library and determine if the underlying is a UEFI Shell 2.0 or an EFI shell.

  @param ImageHandle    the image handle of the process
  @param SystemTable    the EFI System Table pointer

  @retval EFI_SUCCESS   the initialization was complete sucessfully
  @return others        an error ocurred during initialization
**/
EFI_STATUS
EFIAPI
ShellLibConstructor (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  ) {


  mEfiShellEnvironment2       = NULL;
  mEfiShellProtocol           = NULL;
  mEfiShellParametersProtocol = NULL;
  mEfiShellInterface          = NULL;
  mEfiShellEnvironment2Handle = NULL;

  //
  // verify that auto initialize is not set false
  // 
  if (PcdGetBool(PcdShellLibAutoInitialize) == 0) {
    return (EFI_SUCCESS);
  }
  
  return (ShellLibConstructorWorker(ImageHandle, SystemTable));
}

/**
  Destructory for the library.  free any resources.
**/
EFI_STATUS
EFIAPI
ShellLibDestructor (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  ) {
  if (mEfiShellEnvironment2 != NULL) {
    gBS->CloseProtocol(mEfiShellEnvironment2Handle==NULL?ImageHandle:mEfiShellEnvironment2Handle,
                       &gEfiShellEnvironment2Guid,
                       ImageHandle,
                       NULL);
    mEfiShellEnvironment2 = NULL;
  }
  if (mEfiShellInterface != NULL) {
    gBS->CloseProtocol(ImageHandle,
                       &gEfiShellInterfaceGuid,
                       ImageHandle,
                       NULL);  
    mEfiShellInterface = NULL;
  }
  if (mEfiShellProtocol != NULL) {
    gBS->CloseProtocol(ImageHandle,
                       &gEfiShellProtocolGuid,
                       ImageHandle,
                       NULL);  
    mEfiShellProtocol = NULL;
  }
  if (mEfiShellParametersProtocol != NULL) {
    gBS->CloseProtocol(ImageHandle,
                       &gEfiShellParametersProtocolGuid,
                       ImageHandle,
                       NULL);    
    mEfiShellParametersProtocol = NULL;
  }
  mEfiShellEnvironment2Handle = NULL;
  return (EFI_SUCCESS);
}

/**
  This function causes the shell library to initialize itself.  If the shell library
  is already initialized it will de-initialize all the current protocol poitners and
  re-populate them again.

  When the library is used with PcdShellLibAutoInitialize set to true this function
  will return EFI_SUCCESS and perform no actions.

  This function is intended for internal access for shell commands only.

  @retval EFI_SUCCESS   the initialization was complete sucessfully

**/
EFI_STATUS
EFIAPI
ShellInitialize (
  ) {
  //
  // if auto initialize is not false then skip
  //
  if (PcdGetBool(PcdShellLibAutoInitialize) != 0) {
    return (EFI_SUCCESS);
  }

  //
  // deinit the current stuff
  //
  ASSERT_EFI_ERROR(ShellLibDestructor(gImageHandle, gST));

  //
  // init the new stuff
  //
  return (ShellLibConstructorWorker(gImageHandle, gST));
}

/**
  This function will retrieve the information about the file for the handle 
  specified and store it in allocated pool memory.

  This function allocates a buffer to store the file's information. It is the 
  caller's responsibility to free the buffer

  @param  FileHandle  The file handle of the file for which information is 
  being requested.

  @retval NULL information could not be retrieved.

  @return the information about the file
**/
EFI_FILE_INFO*
EFIAPI
ShellGetFileInfo (
  IN EFI_FILE_HANDLE            FileHandle
  ) {
  return (FileFunctionMap.GetFileInfo(FileHandle));
}

/**
  This function will set the information about the file for the opened handle 
  specified.

  @param  FileHandle            The file handle of the file for which information 
  is being set

  @param  FileInfo              The infotmation to set.

  @retval EFI_SUCCESS		The information was set.
  @retval EFI_UNSUPPORTED The InformationType is not known.
  @retval EFI_NO_MEDIA		The device has no medium.
  @retval EFI_DEVICE_ERROR	The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED	The file or medium is write protected.
  @retval EFI_ACCESS_DENIED	The file was opened read only.
  @retval EFI_VOLUME_FULL	The volume is full.
**/
EFI_STATUS
EFIAPI
ShellSetFileInfo (
  IN EFI_FILE_HANDLE  	        FileHandle,
  IN EFI_FILE_INFO              *FileInfo
  ) {
  return (FileFunctionMap.SetFileInfo(FileHandle, FileInfo));
}  
  
  /**
  This function will open a file or directory referenced by DevicePath.

  This function opens a file with the open mode according to the file path. The 
  Attributes is valid only for EFI_FILE_MODE_CREATE.

  @param  FilePath 		    on input the device path to the file.  On output 
                          the remaining device path.
  @param  DeviceHandle  	pointer to the system device handle.
  @param  FileHandle		  pointer to the file handle.
  @param  OpenMode		    the mode to open the file with.
  @param  Attributes		  the file's file attributes.

  @retval EFI_SUCCESS		        The information was set.
  @retval EFI_INVALID_PARAMETER	One of the parameters has an invalid value.
  @retval EFI_UNSUPPORTED	      Could not open the file path.	
  @retval EFI_NOT_FOUND	        The specified file could not be found on the 
                                device or the file system could not be found on 
                                the device.
  @retval EFI_NO_MEDIA		      The device has no medium.
  @retval EFI_MEDIA_CHANGED	    The device has a different medium in it or the 
                                medium is no longer supported.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED	  The file or medium is write protected.
  @retval EFI_ACCESS_DENIED	The file was opened read only.
  @retval EFI_OUT_OF_RESOURCES	Not enough resources were available to open the 
                                file.
  @retval EFI_VOLUME_FULL	      The volume is full.
**/
EFI_STATUS
EFIAPI
ShellOpenFileByDevicePath(
  IN OUT EFI_DEVICE_PATH_PROTOCOL  	  **FilePath,
  OUT EFI_HANDLE                    	*DeviceHandle,
  OUT EFI_FILE_HANDLE               	*FileHandle,
  IN UINT64                          	OpenMode,
  IN UINT64                          	Attributes
  ) {
  CHAR16      *FileName;
  EFI_STATUS  Status;
  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *EfiSimpleFileSystemProtocol;
  EFI_FILE_HANDLE LastHandle;

  //
  // ASERT for FileHandle, FilePath, and DeviceHandle being NULL
  //
  ASSERT(FilePath != NULL);
  ASSERT(FileHandle != NULL);
  ASSERT(DeviceHandle != NULL);
  // 
  // which shell interface should we use
  //
  if (mEfiShellProtocol != NULL) {
    //
    // use UEFI Shell 2.0 method.
    //
    FileName = mEfiShellProtocol->GetFilePathFromDevicePath(*FilePath);
    if (FileName == NULL) {
      return (EFI_INVALID_PARAMETER);
    }
    Status = ShellOpenFileByName(FileName, FileHandle, OpenMode, Attributes);
    FreePool(FileName);
    return (Status);
  } 


  //
  // use old shell method.
  //
  Status = gBS->LocateDevicePath (&gEfiSimpleFileSystemProtocolGuid, 
                                  FilePath, 
                                  DeviceHandle);
  if (EFI_ERROR (Status)) {
    return Status;
  }
  Status = gBS->OpenProtocol(*DeviceHandle,
                             &gEfiSimpleFileSystemProtocolGuid,
                             (VOID**)&EfiSimpleFileSystemProtocol,
                             gImageHandle,
                             NULL,
                             EFI_OPEN_PROTOCOL_GET_PROTOCOL);
  if (EFI_ERROR (Status)) {
    return Status;
  }
  Status = EfiSimpleFileSystemProtocol->OpenVolume(EfiSimpleFileSystemProtocol, FileHandle);
  if (EFI_ERROR (Status)) {
    FileHandle = NULL;
    return Status;
  }

  //
  // go down directories one node at a time.
  //
  while (!IsDevicePathEnd (*FilePath)) {
    //
    // For file system access each node should be a file path component
    //
    if (DevicePathType    (*FilePath) != MEDIA_DEVICE_PATH ||
        DevicePathSubType (*FilePath) != MEDIA_FILEPATH_DP
        ) {
      FileHandle = NULL;
      return (EFI_INVALID_PARAMETER);
    }
    //
    // Open this file path node
    //
    LastHandle  = *FileHandle;
    *FileHandle = NULL;

    //
    // Try to test opening an existing file
    //
    Status = LastHandle->Open (
                          LastHandle,
                          FileHandle,
                          ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName,
                          OpenMode &~EFI_FILE_MODE_CREATE,
                          0
                          );

    //
    // see if the error was that it needs to be created
    //
    if ((EFI_ERROR (Status)) && (OpenMode != (OpenMode &~EFI_FILE_MODE_CREATE))) {
      Status = LastHandle->Open (
                            LastHandle,
                            FileHandle,
                            ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName,
                            OpenMode,
                            Attributes
                            );
    }
    //
    // Close the last node
    //
    LastHandle->Close (LastHandle);

    if (EFI_ERROR(Status)) {
      return (Status);
    }

    //
    // Get the next node
    //
    *FilePath = NextDevicePathNode (*FilePath);
  }
  return (EFI_SUCCESS);
}

/**
  This function will open a file or directory referenced by filename.

  If return is EFI_SUCCESS, the Filehandle is the opened file's handle; 
  otherwise, the Filehandle is NULL. The Attributes is valid only for 
  EFI_FILE_MODE_CREATE.

  if FileNAme is NULL then ASSERT()

  @param  FileName 		  pointer to file name
  @param  FileHandle		pointer to the file handle.
  @param  OpenMode		  the mode to open the file with.
  @param  Attributes		the file's file attributes.

  @retval EFI_SUCCESS		        The information was set.
  @retval EFI_INVALID_PARAMETER	One of the parameters has an invalid value.
  @retval EFI_UNSUPPORTED	      Could not open the file path.	
  @retval EFI_NOT_FOUND	        The specified file could not be found on the 
                                device or the file system could not be found 
                                on the device.
  @retval EFI_NO_MEDIA		      The device has no medium.
  @retval EFI_MEDIA_CHANGED	    The device has a different medium in it or the 
                                medium is no longer supported.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED	  The file or medium is write protected.
  @retval EFI_ACCESS_DENIED	    The file was opened read only.
  @retval EFI_OUT_OF_RESOURCES	Not enough resources were available to open the 
                                file.
  @retval EFI_VOLUME_FULL	      The volume is full.
**/
EFI_STATUS
EFIAPI
ShellOpenFileByName(
  IN CONST CHAR16		            *FileName,
  OUT EFI_FILE_HANDLE           *FileHandle,
  IN UINT64                     OpenMode,
  IN UINT64                    	Attributes
  ) {
  EFI_HANDLE                    DeviceHandle;
  EFI_DEVICE_PATH_PROTOCOL      *FilePath;
  EFI_STATUS                    Status;
  EFI_FILE_INFO                 *FileInfo;

  //
  // ASSERT if FileName is NULL
  //
  ASSERT(FileName != NULL);

  if (mEfiShellProtocol != NULL) {
    //
    // Use UEFI Shell 2.0 method
    //
    Status = mEfiShellProtocol->OpenFileByName(FileName,
                                               FileHandle,
                                               OpenMode);
    if (!EFI_ERROR(Status) && ((OpenMode & EFI_FILE_MODE_CREATE) != 0)){
      FileInfo = FileFunctionMap.GetFileInfo(*FileHandle);
      ASSERT(FileInfo != NULL);
      FileInfo->Attribute = Attributes;
      Status = FileFunctionMap.SetFileInfo(*FileHandle, FileInfo);
      FreePool(FileInfo);
    }
    return (Status);
  } 
  //
  // Using EFI Shell version
  // this means convert name to path and call that function
  // since this will use EFI method again that will open it.
  //
  ASSERT(mEfiShellEnvironment2 != NULL);
  FilePath = mEfiShellEnvironment2->NameToPath ((CHAR16*)FileName);
  if (FileDevicePath != NULL) {
    return (ShellOpenFileByDevicePath(&FilePath,
                                      &DeviceHandle,
                                      FileHandle,
                                      OpenMode,
                                      Attributes ));
  }
  return (EFI_DEVICE_ERROR);
}
/**
  This function create a directory

  If return is EFI_SUCCESS, the Filehandle is the opened directory's handle; 
  otherwise, the Filehandle is NULL. If the directory already existed, this 
  function opens the existing directory.

  @param  DirectoryName		pointer to directory name
  @param  FileHandle		  pointer to the file handle.

  @retval EFI_SUCCESS		        The information was set.
  @retval EFI_INVALID_PARAMETER	One of the parameters has an invalid value.
  @retval EFI_UNSUPPORTED	      Could not open the file path.	
  @retval EFI_NOT_FOUND	        The specified file could not be found on the 
                                device or the file system could not be found 
                                on the device.
  @retval EFI_NO_MEDIA		      The device has no medium.
  @retval EFI_MEDIA_CHANGED	    The device has a different medium in it or the 
                                medium is no longer supported.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED	  The file or medium is write protected.
  @retval EFI_ACCESS_DENIED	    The file was opened read only.
  @retval EFI_OUT_OF_RESOURCES	Not enough resources were available to open the 
                                file.
  @retval EFI_VOLUME_FULL	      The volume is full.
  @sa ShellOpenFileByName
**/
EFI_STATUS
EFIAPI
ShellCreateDirectory(
  IN CONST CHAR16             *DirectoryName,
  OUT EFI_FILE_HANDLE         *FileHandle
  ) {
  if (mEfiShellProtocol != NULL) {
    //
    // Use UEFI Shell 2.0 method
    //
    return (mEfiShellProtocol->CreateFile(DirectoryName,
                          EFI_FILE_DIRECTORY,
                          FileHandle
                          ));
  } else {
    return (ShellOpenFileByName(DirectoryName,
                                FileHandle,
                                EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE | EFI_FILE_MODE_CREATE,
                                EFI_FILE_DIRECTORY
                                ));
  }
}

/**
  This function reads information from an opened file.

  If FileHandle is not a directory, the function reads the requested number of 
  bytes from the file at the file's current position and returns them in Buffer. 
  If the read goes beyond the end of the file, the read length is truncated to the
  end of the file. The file's current position is increased by the number of bytes 
  returned.  If FileHandle is a directory, the function reads the directory entry 
  at the file's current position and returns the entry in Buffer. If the Buffer 
  is not large enough to hold the current directory entry, then 
  EFI_BUFFER_TOO_SMALL is returned and the current file position is not updated. 
  BufferSize is set to be the size of the buffer needed to read the entry. On 
  success, the current position is updated to the next directory entry. If there 
  are no more directory entries, the read returns a zero-length buffer. 
  EFI_FILE_INFO is the structure returned as the directory entry.

  @param FileHandle             the opened file handle
  @param BufferSize             on input the size of buffer in bytes.  on return 
                                the number of bytes written.
  @param Buffer                 the buffer to put read data into.

  @retval EFI_SUCCESS	          Data was read.
  @retval EFI_NO_MEDIA	        The device has no media.
  @retval EFI_DEVICE_ERROR	The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_BUFFER_TO_SMALL	Buffer is too small. ReadSize contains required 
                                size.

**/
EFI_STATUS
EFIAPI
ShellReadFile(
  IN EFI_FILE_HANDLE            FileHandle,
  IN OUT UINTN                  *BufferSize,
  OUT VOID                      *Buffer
  ) {
  return (FileFunctionMap.ReadFile(FileHandle, BufferSize, Buffer));
}


/**
  Write data to a file.

  This function writes the specified number of bytes to the file at the current 
  file position. The current file position is advanced the actual number of bytes 
  written, which is returned in BufferSize. Partial writes only occur when there 
  has been a data error during the write attempt (such as "volume space full"). 
  The file is automatically grown to hold the data if required. Direct writes to 
  opened directories are not supported.

  @param FileHandle           The opened file for writing
  @param BufferSize           on input the number of bytes in Buffer.  On output
                              the number of bytes written.
  @param Buffer               the buffer containing data to write is stored.

 @retval EFI_SUCCESS	        Data was written.
 @retval EFI_UNSUPPORTED	    Writes to an open directory are not supported.
 @retval EFI_NO_MEDIA	        The device has no media.
 @retval EFI_DEVICE_ERROR	    The device reported an error.
 @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
 @retval EFI_WRITE_PROTECTED	The device is write-protected.
 @retval EFI_ACCESS_DENIED	  The file was open for read only.
 @retval EFI_VOLUME_FULL	    The volume is full.
**/
EFI_STATUS
EFIAPI
ShellWriteFile(
  IN EFI_FILE_HANDLE            FileHandle,
  IN OUT UINTN                  *BufferSize,
  IN VOID                       *Buffer
  ) {
  return (FileFunctionMap.WriteFile(FileHandle, BufferSize, Buffer));
}

/** 
  Close an open file handle.

  This function closes a specified file handle. All "dirty" cached file data is 
  flushed to the device, and the file is closed. In all cases the handle is 
  closed.

@param FileHandle               the file handle to close.

@retval EFI_SUCCESS             the file handle was closed sucessfully.
**/
EFI_STATUS
EFIAPI
ShellCloseFile (
  IN EFI_FILE_HANDLE            *FileHandle
  ) {
  return (FileFunctionMap.CloseFile(*FileHandle));
}

/**
  Delete a file and close the handle

  This function closes and deletes a file. In all cases the file handle is closed.
  If the file cannot be deleted, the warning code EFI_WARN_DELETE_FAILURE is 
  returned, but the handle is still closed.

  @param FileHandle             the file handle to delete

  @retval EFI_SUCCESS           the file was closed sucessfully
  @retval EFI_WARN_DELETE_FAILURE the handle was closed, but the file was not 
                                deleted
  @retval INVALID_PARAMETER    	One of the parameters has an invalid value.
**/
EFI_STATUS
EFIAPI
ShellDeleteFile (
  IN EFI_FILE_HANDLE		*FileHandle
  ) {
  return (FileFunctionMap.DeleteFile(*FileHandle));
}

/**
  Set the current position in a file.

  This function sets the current file position for the handle to the position 
  supplied. With the exception of seeking to position 0xFFFFFFFFFFFFFFFF, only
  absolute positioning is supported, and seeking past the end of the file is 
  allowed (a subsequent write would grow the file). Seeking to position 
  0xFFFFFFFFFFFFFFFF causes the current position to be set to the end of the file.
  If FileHandle is a directory, the only position that may be set is zero. This 
  has the effect of starting the read process of the directory entries over.

  @param FileHandle             The file handle on which the position is being set
  @param Position               Byte position from begining of file

  @retval EFI_SUCCESS           Operation completed sucessfully.
  @retval EFI_UNSUPPORTED       the seek request for non-zero is not valid on 
                                directories.
  @retval INVALID_PARAMETER     One of the parameters has an invalid value.
**/
EFI_STATUS
EFIAPI
ShellSetFilePosition (
  IN EFI_FILE_HANDLE   	FileHandle,
  IN UINT64           	Position
  ) {
  return (FileFunctionMap.SetFilePosition(FileHandle, Position));
}

/** 
  Gets a file's current position

  This function retrieves the current file position for the file handle. For 
  directories, the current file position has no meaning outside of the file 
  system driver and as such the operation is not supported. An error is returned
  if FileHandle is a directory.

  @param FileHandle             The open file handle on which to get the position.
  @param Position               Byte position from begining of file.

  @retval EFI_SUCCESS           the operation completed sucessfully.
  @retval INVALID_PARAMETER     One of the parameters has an invalid value.
  @retval EFI_UNSUPPORTED       the request is not valid on directories.
**/
EFI_STATUS
EFIAPI
ShellGetFilePosition (
  IN EFI_FILE_HANDLE            FileHandle,
  OUT UINT64                    *Position
  ) {
  return (FileFunctionMap.GetFilePosition(FileHandle, Position));
}
/**
  Flushes data on a file
  
  This function flushes all modified data associated with a file to a device.

  @param FileHandle             The file handle on which to flush data

  @retval EFI_SUCCESS           The data was flushed.
  @retval EFI_NO_MEDIA          The device has no media.
  @retval EFI_DEVICE_ERROR      The device reported an error.
  @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED   The file or medium is write protected.
  @retval EFI_ACCESS_DENIED     The file was opened for read only.
**/
EFI_STATUS
EFIAPI
ShellFlushFile (
  IN EFI_FILE_HANDLE            FileHandle
  ) {
  return (FileFunctionMap.FlushFile(FileHandle));
}

/**
  Retrieves the first file from a directory

  This function opens a directory and gets the first file's info in the 
  directory. Caller can use ShellFindNextFile() to get other files.  When 
  complete the caller is responsible for calling FreePool() on Buffer.

  @param DirHandle              The file handle of the directory to search
  @param Buffer                 Pointer to buffer for file's information

  @retval EFI_SUCCESS           Found the first file.
  @retval EFI_NOT_FOUND         Cannot find the directory.
  @retval EFI_NO_MEDIA          The device has no media.
  @retval EFI_DEVICE_ERROR      The device reported an error.
  @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
  @return Others                status of ShellGetFileInfo, ShellSetFilePosition,
                                or ShellReadFile
**/
EFI_STATUS
EFIAPI
ShellFindFirstFile (
  IN EFI_FILE_HANDLE            DirHandle,
  OUT EFI_FILE_INFO             **Buffer
  ) {
  //
  // pass to file handle lib
  //
  return (FileHandleFindFirstFile(DirHandle, Buffer));
}
/**
  Retrieves the next file in a directory.

  To use this function, caller must call the LibFindFirstFile() to get the 
  first file, and then use this function get other files. This function can be 
  called for several times to get each file's information in the directory. If 
  the call of ShellFindNextFile() got the last file in the directory, the next 
  call of this function has no file to get. *NoFile will be set to TRUE and the 
  Buffer memory will be automatically freed. 

  @param DirHandle              the file handle of the directory
  @param Buffer			            pointer to buffer for file's information
  @param NoFile			            pointer to boolean when last file is found

  @retval EFI_SUCCESS           Found the next file, or reached last file
  @retval EFI_NO_MEDIA          The device has no media.
  @retval EFI_DEVICE_ERROR      The device reported an error.
  @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
**/
EFI_STATUS
EFIAPI
ShellFindNextFile(
  IN EFI_FILE_HANDLE             DirHandle,
  OUT EFI_FILE_INFO              *Buffer,
  OUT BOOLEAN                    *NoFile
  ) {
  //
  // pass to file handle lib
  //
  return (FileHandleFindNextFile(DirHandle, Buffer, NoFile));
}
/**
  Retrieve the size of a file.

  if FileHandle is NULL then ASSERT()
  if Size is NULL then ASSERT()

  This function extracts the file size info from the FileHandle's EFI_FILE_INFO 
  data.

  @param FileHandle             file handle from which size is retrieved
  @param Size                   pointer to size

  @retval EFI_SUCCESS           operation was completed sucessfully
  @retval EFI_DEVICE_ERROR      cannot access the file
**/
EFI_STATUS
EFIAPI
ShellGetFileSize (
  IN EFI_FILE_HANDLE            FileHandle,
  OUT UINT64                    *Size
  ) {
  return (FileFunctionMap.GetFileSize(FileHandle, Size));
}
/**
  Retrieves the status of the break execution flag

  this function is useful to check whether the application is being asked to halt by the shell.

  @retval TRUE                  the execution break is enabled
  @retval FALSE                 the execution break is not enabled
**/
BOOLEAN
EFIAPI
ShellGetExecutionBreakFlag(
  VOID
  )
{
  // 
  // Check for UEFI Shell 2.0 protocols
  //
  if (mEfiShellProtocol != NULL) {

    //
    // We are using UEFI Shell 2.0; see if the event has been triggered
    //
    if (gBS->CheckEvent(mEfiShellProtocol->ExecutionBreak) != EFI_SUCCESS) {
      return (FALSE);
    }
    return (TRUE);
  } 

  //
  // using EFI Shell; call the function to check
  //
  ASSERT(mEfiShellEnvironment2 != NULL);
  return (mEfiShellEnvironment2->GetExecutionBreak());
}
/**
  return the value of an environment variable

  this function gets the value of the environment variable set by the 
  ShellSetEnvironmentVariable function

  @param EnvKey                 The key name of the environment variable.

  @retval NULL                  the named environment variable does not exist.
  @return != NULL               pointer to the value of the environment variable
**/
CONST CHAR16*
EFIAPI
ShellGetEnvironmentVariable (
  IN CONST CHAR16                *EnvKey
  )
{
  // 
  // Check for UEFI Shell 2.0 protocols
  //
  if (mEfiShellProtocol != NULL) {
    return (mEfiShellProtocol->GetEnv(EnvKey));
  }

  //
  // ASSERT that we must have EFI shell
  //
  ASSERT(mEfiShellEnvironment2 != NULL);

  //
  // using EFI Shell
  //
  return (mEfiShellEnvironment2->GetEnv((CHAR16*)EnvKey));
}
/**
  set the value of an environment variable

This function changes the current value of the specified environment variable. If the
environment variable exists and the Value is an empty string, then the environment
variable is deleted. If the environment variable exists and the Value is not an empty
string, then the value of the environment variable is changed. If the environment
variable does not exist and the Value is an empty string, there is no action. If the
environment variable does not exist and the Value is a non-empty string, then the
environment variable is created and assigned the specified value.

  This is not supported pre-UEFI Shell 2.0.

  @param EnvKey                 The key name of the environment variable.
  @param EnvVal                 The Value of the environment variable
  @param Volatile               Indicates whether the variable is non-volatile (FALSE) or volatile (TRUE).

  @retval EFI_SUCCESS           the operation was completed sucessfully
  @retval EFI_UNSUPPORTED       This operation is not allowed in pre UEFI 2.0 Shell environments
**/
EFI_STATUS
EFIAPI
ShellSetEnvironmentVariable (
  IN CONST CHAR16               *EnvKey,
  IN CONST CHAR16               *EnvVal,
  IN BOOLEAN                    Volatile
  )
{
  // 
  // Check for UEFI Shell 2.0 protocols
  //
  if (mEfiShellProtocol != NULL) {
    return (mEfiShellProtocol->SetEnv(EnvKey, EnvVal, Volatile));
  } 

  //
  // This feature does not exist under EFI shell
  //
  return (EFI_UNSUPPORTED);
}
/**
  cause the shell to parse and execute a command line.

  This function creates a nested instance of the shell and executes the specified
command (CommandLine) with the specified environment (Environment). Upon return,
the status code returned by the specified command is placed in StatusCode.
If Environment is NULL, then the current environment is used and all changes made
by the commands executed will be reflected in the current environment. If the
Environment is non-NULL, then the changes made will be discarded.
The CommandLine is executed from the current working directory on the current
device.

EnvironmentVariables and Status are only supported for UEFI Shell 2.0.
Output is only supported for pre-UEFI Shell 2.0

  @param ImageHandle            Parent image that is starting the operation
  @param CommandLine            pointer to null terminated command line.
  @param Output                 true to display debug output.  false to hide it.
  @param EnvironmentVariables   optional pointer to array of environment variables
                                in the form "x=y".  if NULL current set is used.
  @param Status                 the status of the run command line.

  @retval EFI_SUCCESS           the operation completed sucessfully.  Status
                                contains the status code returned.
  @retval EFI_INVALID_PARAMETER a parameter contains an invalid value
  @retval EFI_OUT_OF_RESOURCES  out of resources
  @retval EFI_UNSUPPORTED       the operation is not allowed.
**/
EFI_STATUS
EFIAPI
ShellExecute (
  IN EFI_HANDLE                 *ParentHandle,
  IN CHAR16                     *CommandLine OPTIONAL,
  IN BOOLEAN                    Output OPTIONAL,
  IN CHAR16                     **EnvironmentVariables OPTIONAL,
  OUT EFI_STATUS                *Status OPTIONAL
  )
{
  // 
  // Check for UEFI Shell 2.0 protocols
  //
  if (mEfiShellProtocol != NULL) {
    //
    // Call UEFI Shell 2.0 version (not using Output parameter)
    //
    return (mEfiShellProtocol->Execute(ParentHandle,
                                      CommandLine,
                                      EnvironmentVariables,
                                      Status));
  } 
  //
  // ASSERT that we must have EFI shell
  //
  ASSERT(mEfiShellEnvironment2 != NULL);
  //
  // Call EFI Shell version (not using EnvironmentVariables or Status parameters)
  // Due to oddity in the EFI shell we want to dereference the ParentHandle here
  //
  return (mEfiShellEnvironment2->Execute(*ParentHandle, 
                                        CommandLine, 
                                        Output));
}
/**
  Retreives the current directory path

  If the DeviceName is NULL, it returns the current device's current directory 
  name. If the DeviceName is not NULL, it returns the current directory name 
  on specified drive.

  @param DeviceName             the name of the drive to get directory on

  @retval NULL                  the directory does not exist
  @return != NULL               the directory
**/
CONST CHAR16*
EFIAPI
ShellGetCurrentDir (
  IN CHAR16                     *DeviceName OPTIONAL
  )
{
  // 
  // Check for UEFI Shell 2.0 protocols
  //
  if (mEfiShellProtocol != NULL) {
    return (mEfiShellProtocol->GetCurDir(DeviceName));
  } 
  //
  // ASSERT that we must have EFI shell
  //
  ASSERT(mEfiShellEnvironment2 != NULL);
  return (mEfiShellEnvironment2->CurDir(DeviceName));
}
/**
  sets (enabled or disabled) the page break mode

  when page break mode is enabled the screen will stop scrolling 
  and wait for operator input before scrolling a subsequent screen.

  @param CurrentState           TRUE to enable and FALSE to disable
**/
VOID 
EFIAPI
ShellSetPageBreakMode (
  IN BOOLEAN                    CurrentState
  )
{
  //
  // check for enabling
  //
  if (CurrentState != 0x00) {
    // 
    // check for UEFI Shell 2.0
    //
    if (mEfiShellProtocol != NULL) {
      //
      // Enable with UEFI 2.0 Shell
      //
      mEfiShellProtocol->EnablePageBreak();
      return;
    } else {
      // 
      // ASSERT that must have EFI Shell
      //
      ASSERT(mEfiShellEnvironment2 != NULL);
      //
      // Enable with EFI Shell
      //
      mEfiShellEnvironment2->EnablePageBreak (DEFAULT_INIT_ROW, DEFAULT_AUTO_LF);
      return;
    }
  } else {
    // 
    // check for UEFI Shell 2.0
    //
    if (mEfiShellProtocol != NULL) {
      //
      // Disable with UEFI 2.0 Shell
      //
      mEfiShellProtocol->DisablePageBreak();
      return;
    } else {
      // 
      // ASSERT that must have EFI Shell
      //
      ASSERT(mEfiShellEnvironment2 != NULL);
      //
      // Disable with EFI Shell
      //
      mEfiShellEnvironment2->DisablePageBreak ();
      return;
    }
  }
}

///
/// version of EFI_SHELL_FILE_INFO struct, except has no CONST pointers.
/// This allows for the struct to be populated.
///
typedef struct {
  LIST_ENTRY Link;
  EFI_STATUS Status;
  CHAR16 *FullName;
  CHAR16 *FileName;
  EFI_FILE_HANDLE Handle;
  EFI_FILE_INFO *Info;
} EFI_SHELL_FILE_INFO_NO_CONST;

/**
  Converts a EFI shell list of structures to the coresponding UEFI Shell 2.0 type of list.

  if OldStyleFileList is NULL then ASSERT()

  this function will convert a SHELL_FILE_ARG based list into a callee allocated 
  EFI_SHELL_FILE_INFO based list.  it is up to the caller to free the memory via
  the ShellCloseFileMetaArg function.

  @param[in] FileList           the EFI shell list type
  @param[in,out] ListHead      the list to add to

  @retval the resultant head of the double linked new format list;
**/
LIST_ENTRY*
EFIAPI
InternalShellConvertFileListType (
  IN LIST_ENTRY                 *FileList,
  IN OUT LIST_ENTRY             *ListHead
  )
{
  SHELL_FILE_ARG                *OldInfo;
  LIST_ENTRY                    *Link;
  EFI_SHELL_FILE_INFO_NO_CONST  *NewInfo;

  //
  // ASSERTs
  //
  ASSERT(FileList  != NULL);
  ASSERT(ListHead  != NULL);

  //
  // enumerate through each member of the old list and copy
  //
  for (Link = FileList->ForwardLink; Link != FileList; Link = Link->ForwardLink) {
    OldInfo = CR (Link, SHELL_FILE_ARG, Link, SHELL_FILE_ARG_SIGNATURE);

    //
    // make sure the old list was valid
    //
    ASSERT(OldInfo           != NULL); 
    ASSERT(OldInfo->Info     != NULL);
    ASSERT(OldInfo->FullName != NULL);
    ASSERT(OldInfo->FileName != NULL);

    //
    // allocate a new EFI_SHELL_FILE_INFO object
    //
    NewInfo               = AllocateZeroPool(sizeof(EFI_SHELL_FILE_INFO));
    
    // 
    // copy the simple items
    //
    NewInfo->Handle       = OldInfo->Handle;
    NewInfo->Status       = OldInfo->Status;

    // old shell checks for 0 not NULL
    OldInfo->Handle = 0;

    //
    // allocate new space to copy strings and structure
    //
    NewInfo->FullName     = AllocateZeroPool(StrSize(OldInfo->FullName));
    NewInfo->FileName     = AllocateZeroPool(StrSize(OldInfo->FileName));
    NewInfo->Info         = AllocateZeroPool((UINTN)OldInfo->Info->Size);
    
    //
    // make sure all the memory allocations were sucessful
    //
    ASSERT(NewInfo->FullName != NULL);
    ASSERT(NewInfo->FileName != NULL);
    ASSERT(NewInfo->Info     != NULL);

    //
    // Copt the strings and structure
    //
    StrCpy(NewInfo->FullName, OldInfo->FullName);
    StrCpy(NewInfo->FileName, OldInfo->FileName);
    gBS->CopyMem (NewInfo->Info, OldInfo->Info, (UINTN)OldInfo->Info->Size);

    //
    // add that to the list
    //
    InsertTailList(ListHead, &NewInfo->Link);
  }
  return (ListHead);
}
/**
  Opens a group of files based on a path.

  This function uses the Arg to open all the matching files. Each matched 
  file has a SHELL_FILE_ARG structure to record the file information. These 
  structures are placed on the list ListHead. Users can get the SHELL_FILE_ARG 
  structures from ListHead to access each file. This function supports wildcards
  and will process '?' and '*' as such.  the list must be freed with a call to 
  ShellCloseFileMetaArg().

  If you are NOT appending to an existing list *ListHead must be NULL.  If 
  *ListHead is NULL then it must be callee freed.

  @param Arg                    pointer to path string
  @param OpenMode               mode to open files with
  @param ListHead               head of linked list of results

  @retval EFI_SUCCESS           the operation was sucessful and the list head 
                                contains the list of opened files
  #retval EFI_UNSUPPORTED       a previous ShellOpenFileMetaArg must be closed first.
                                *ListHead is set to NULL.
  @return != EFI_SUCCESS        the operation failed

  @sa InternalShellConvertFileListType
**/
EFI_STATUS
EFIAPI
ShellOpenFileMetaArg (
  IN CHAR16                     *Arg,
  IN UINT64                     OpenMode,
  IN OUT EFI_SHELL_FILE_INFO    **ListHead
  )
{
  EFI_STATUS                    Status;
  LIST_ENTRY                    mOldStyleFileList;
  
  //
  // ASSERT that Arg and ListHead are not NULL
  //
  ASSERT(Arg      != NULL);
  ASSERT(ListHead != NULL);

  // 
  // Check for UEFI Shell 2.0 protocols
  //
  if (mEfiShellProtocol != NULL) {
    if (*ListHead == NULL) {
      *ListHead = (EFI_SHELL_FILE_INFO*)AllocateZeroPool(sizeof(EFI_SHELL_FILE_INFO));
      if (*ListHead == NULL) {
        return (EFI_OUT_OF_RESOURCES);
      }
      InitializeListHead(&((*ListHead)->Link));
    }    
    Status = mEfiShellProtocol->OpenFileList(Arg, 
                                           OpenMode, 
                                           ListHead);
    if (EFI_ERROR(Status)) {
      mEfiShellProtocol->RemoveDupInFileList(ListHead);
    } else {
      Status = mEfiShellProtocol->RemoveDupInFileList(ListHead);
    }
    return (Status);
  } 

  //
  // ASSERT that we must have EFI shell
  //
  ASSERT(mEfiShellEnvironment2 != NULL);

  //
  // make sure the list head is initialized
  //
  InitializeListHead(&mOldStyleFileList);

  //
  // Get the EFI Shell list of files
  //
  Status = mEfiShellEnvironment2->FileMetaArg(Arg, &mOldStyleFileList);
  if (EFI_ERROR(Status)) {
    *ListHead = NULL;
    return (Status);
  }

  if (*ListHead == NULL) {
    *ListHead = (EFI_SHELL_FILE_INFO    *)AllocateZeroPool(sizeof(EFI_SHELL_FILE_INFO));
    if (*ListHead == NULL) {
      return (EFI_OUT_OF_RESOURCES);
    }
  }

  //
  // Convert that to equivalent of UEFI Shell 2.0 structure
  //
  InternalShellConvertFileListType(&mOldStyleFileList, &(*ListHead)->Link);

  //
  // Free the EFI Shell version that was converted.
  //
  mEfiShellEnvironment2->FreeFileList(&mOldStyleFileList);

  return (Status);
}
/**
  Free the linked list returned from ShellOpenFileMetaArg

  if ListHead is NULL then ASSERT()

  @param ListHead               the pointer to free

  @retval EFI_SUCCESS           the operation was sucessful
**/
EFI_STATUS
EFIAPI
ShellCloseFileMetaArg (
  IN OUT EFI_SHELL_FILE_INFO    **ListHead
  )
{
  LIST_ENTRY                    *Node;

  //
  // ASSERT that ListHead is not NULL
  //
  ASSERT(ListHead != NULL);

  // 
  // Check for UEFI Shell 2.0 protocols
  //
  if (mEfiShellProtocol != NULL) {
    return (mEfiShellProtocol->FreeFileList(ListHead));
  } else {
    //
    // Since this is EFI Shell version we need to free our internally made copy 
    // of the list
    //
    for ( Node = GetFirstNode(&(*ListHead)->Link) 
        ; IsListEmpty(&(*ListHead)->Link) == FALSE 
        ; Node = GetFirstNode(&(*ListHead)->Link)) {
      RemoveEntryList(Node);
      ((EFI_SHELL_FILE_INFO_NO_CONST*)Node)->Handle->Close(((EFI_SHELL_FILE_INFO_NO_CONST*)Node)->Handle);
      FreePool(((EFI_SHELL_FILE_INFO_NO_CONST*)Node)->FullName);
      FreePool(((EFI_SHELL_FILE_INFO_NO_CONST*)Node)->FileName);
      FreePool(((EFI_SHELL_FILE_INFO_NO_CONST*)Node)->Info);
      FreePool((EFI_SHELL_FILE_INFO_NO_CONST*)Node);
    }
    return EFI_SUCCESS;
  }
}

/**
  Find a file by searching the CWD and then the path.

  if FileName is NULL then ASSERT.

  if the return value is not NULL then the memory must be caller freed.

  @param FileName               Filename string.

  @retval NULL                  the file was not found
  @return !NULL                 the full path to the file.
**/
CHAR16 *
EFIAPI
ShellFindFilePath (
  IN CONST CHAR16 *FileName
  )
{
  CONST CHAR16      *Path;
  EFI_FILE_HANDLE   Handle;
  EFI_STATUS        Status;
  CHAR16            *RetVal;
  CHAR16            *TestPath;
  CONST CHAR16      *Walker;
  UINTN             Size;

  RetVal = NULL;

  Path = ShellGetEnvironmentVariable(L"cwd");
  if (Path != NULL) {
    Size = StrSize(Path);
    Size += StrSize(FileName);
    TestPath = AllocateZeroPool(Size);
    StrCpy(TestPath, Path);
    StrCat(TestPath, FileName);
    Status = ShellOpenFileByName(TestPath, &Handle, EFI_FILE_MODE_READ, 0);
    if (!EFI_ERROR(Status)){
      RetVal = StrnCatGrow(&RetVal, NULL, TestPath, 0);
      ShellCloseFile(&Handle);
      FreePool(TestPath);
      return (RetVal);
    }
    FreePool(TestPath);
  }
  Path = ShellGetEnvironmentVariable(L"path");
  if (Path != NULL) {
    Size = StrSize(Path);
    Size += StrSize(FileName);
    TestPath = AllocateZeroPool(Size);
    Walker = (CHAR16*)Path; 
    do {
      CopyMem(TestPath, Walker, StrSize(Walker));
      if (StrStr(TestPath, L";") != NULL) {
        *(StrStr(TestPath, L";")) = CHAR_NULL;
      }
      StrCat(TestPath, FileName);
      if (StrStr(Walker, L";") != NULL) {
        Walker = StrStr(Walker, L";") + 1;
      } else {
        Walker = NULL;
      }
      Status = ShellOpenFileByName(TestPath, &Handle, EFI_FILE_MODE_READ, 0);
      if (!EFI_ERROR(Status)){
        RetVal = StrnCatGrow(&RetVal, NULL, TestPath, 0);
        ShellCloseFile(&Handle);
        break;
      }
    } while (Walker != NULL && Walker[0] != CHAR_NULL);
    FreePool(TestPath);
  }
  return (RetVal);
}

typedef struct {
  LIST_ENTRY     Link;
  CHAR16         *Name;
  ParamType      Type;
  CHAR16         *Value;
  UINTN          OriginalPosition;
} SHELL_PARAM_PACKAGE;

/**
  Checks the list of valid arguments and returns TRUE if the item was found.  If the 
  return value is TRUE then the type parameter is set also.
  
  if CheckList is NULL then ASSERT();
  if Name is NULL then ASSERT();
  if Type is NULL then ASSERT();

  @param Type                   pointer to type of parameter if it was found
  @param Name                   pointer to Name of parameter found
  @param CheckList              List to check against

  @retval TRUE                  the Parameter was found.  Type is valid.
  @retval FALSE                 the Parameter was not found.  Type is not valid.
**/
BOOLEAN
EFIAPI
InternalIsOnCheckList (
  IN CONST CHAR16               *Name,
  IN CONST SHELL_PARAM_ITEM     *CheckList,
  OUT ParamType                 *Type
  ) {
  SHELL_PARAM_ITEM              *TempListItem;

  //
  // ASSERT that all 3 pointer parameters aren't NULL
  //
  ASSERT(CheckList  != NULL);
  ASSERT(Type       != NULL);
  ASSERT(Name       != NULL);

  //
  // question mark and page break mode are always supported
  //
  if ((StrCmp(Name, L"-?") == 0) ||
      (StrCmp(Name, L"-b") == 0)
      ) {
     return (TRUE);
  }

  //
  // Enumerate through the list
  //
  for (TempListItem = (SHELL_PARAM_ITEM*)CheckList ; TempListItem->Name != NULL ; TempListItem++) {
    //
    // If the Type is TypeStart only check the first characters of the passed in param
    // If it matches set the type and return TRUE
    //
    if (TempListItem->Type == TypeStart && StrnCmp(Name, TempListItem->Name, StrLen(TempListItem->Name)) == 0) {
      *Type = TempListItem->Type;
      return (TRUE);
    } else if (StrCmp(Name, TempListItem->Name) == 0) {
      *Type = TempListItem->Type;
      return (TRUE);
    }
  }

  return (FALSE);
}
/**
  Checks the string for indicators of "flag" status.  this is a leading '/', '-', or '+'

  @param Name                   pointer to Name of parameter found

  @retval TRUE                  the Parameter is a flag.
  @retval FALSE                 the Parameter not a flag
**/
BOOLEAN
EFIAPI
InternalIsFlag (
  IN CONST CHAR16               *Name,
  IN BOOLEAN                    AlwaysAllowNumbers
  )
{
  //
  // ASSERT that Name isn't NULL
  //
  ASSERT(Name != NULL);

  //
  // If we accept numbers then dont return TRUE. (they will be values)
  //
  if (((Name[0] == L'-' || Name[0] == L'+') && ShellInternalIsHexaDecimalDigitCharacter(Name[1])) && AlwaysAllowNumbers == TRUE) {
    return (FALSE);
  }

  //
  // If the Name has a / or - as the first character return TRUE
  //
  if ((Name[0] == L'/') || 
      (Name[0] == L'-') ||
      (Name[0] == L'+')
      ) {
      return (TRUE);
  }
  return (FALSE);
}

/**
  Checks the command line arguments passed against the list of valid ones.  

  If no initialization is required, then return RETURN_SUCCESS.
  
  @param CheckList              pointer to list of parameters to check
  @param CheckPackage           pointer to pointer to list checked values
  @param ProblemParam           optional pointer to pointer to unicode string for 
                                the paramater that caused failure.  If used then the
                                caller is responsible for freeing the memory.
  @param AutoPageBreak          will automatically set PageBreakEnabled for "b" parameter
  @param Argc                   Count of parameters in Argv
  @param Argv                   pointer to array of parameters

  @retval EFI_SUCCESS           The operation completed sucessfully.
  @retval EFI_OUT_OF_RESOURCES  A memory allocation failed
  @retval EFI_INVALID_PARAMETER A parameter was invalid
  @retval EFI_VOLUME_CORRUPTED  the command line was corrupt.  an argument was 
                                duplicated.  the duplicated command line argument 
                                was returned in ProblemParam if provided.
  @retval EFI_NOT_FOUND         a argument required a value that was missing.  
                                the invalid command line argument was returned in
                                ProblemParam if provided.
**/
STATIC
EFI_STATUS
EFIAPI
InternalCommandLineParse (
  IN CONST SHELL_PARAM_ITEM     *CheckList,
  OUT LIST_ENTRY                **CheckPackage,
  OUT CHAR16                    **ProblemParam OPTIONAL,
  IN BOOLEAN                    AutoPageBreak,
  IN CONST CHAR16               **Argv,
  IN UINTN                      Argc,
  IN BOOLEAN                    AlwaysAllowNumbers
  ) {
  UINTN                         LoopCounter;
  ParamType                     CurrentItemType;
  SHELL_PARAM_PACKAGE           *CurrentItemPackage;
  UINTN                         GetItemValue;
  UINTN                         ValueSize;

  CurrentItemPackage = NULL;
  mTotalParameterCount = 0;
  GetItemValue = 0;
  ValueSize = 0;

  //
  // If there is only 1 item we dont need to do anything
  //
  if (Argc <= 1) {
    *CheckPackage = NULL;
    return (EFI_SUCCESS);
  }

  //
  // ASSERTs
  //
  ASSERT(CheckList  != NULL);
  ASSERT(Argv       != NULL);

  //
  // initialize the linked list
  //
  *CheckPackage = (LIST_ENTRY*)AllocateZeroPool(sizeof(LIST_ENTRY));
  InitializeListHead(*CheckPackage);

  //
  // loop through each of the arguments
  //
  for (LoopCounter = 0 ; LoopCounter < Argc ; ++LoopCounter) {
    if (Argv[LoopCounter] == NULL) {
      //
      // do nothing for NULL argv
      //
    } else if (InternalIsOnCheckList(Argv[LoopCounter], CheckList, &CurrentItemType) == TRUE) {
      //
      // We might have leftover if last parameter didnt have optional value
      //
      if (GetItemValue != 0) {
        GetItemValue = 0;
        InsertHeadList(*CheckPackage, &CurrentItemPackage->Link);
      }
      //
      // this is a flag
      //
      CurrentItemPackage = AllocatePool(sizeof(SHELL_PARAM_PACKAGE));
      ASSERT(CurrentItemPackage != NULL);
      CurrentItemPackage->Name  = AllocatePool(StrSize(Argv[LoopCounter]));
      ASSERT(CurrentItemPackage->Name != NULL);
      StrCpy(CurrentItemPackage->Name,  Argv[LoopCounter]);
      CurrentItemPackage->Type  = CurrentItemType;
      CurrentItemPackage->OriginalPosition = (UINTN)(-1);
      CurrentItemPackage->Value = NULL;

      //
      // Does this flag require a value
      //
      switch (CurrentItemPackage->Type) {
        //
        // possibly trigger the next loop(s) to populate the value of this item
        //        
        case TypeValue:
          GetItemValue = 1; 
          ValueSize = 0;
          break;
        case TypeDoubleValue:
          GetItemValue = 2;
          ValueSize = 0;
          break;
        case TypeMaxValue:
          GetItemValue = (UINTN)(-1);
          ValueSize = 0;
          break;
        default:
          //
          // this item has no value expected; we are done
          //
          InsertHeadList(*CheckPackage, &CurrentItemPackage->Link);
          ASSERT(GetItemValue == 0);
          break;
      }
    } else if (GetItemValue != 0 && InternalIsFlag(Argv[LoopCounter], AlwaysAllowNumbers) == FALSE) {
      ASSERT(CurrentItemPackage != NULL);
      //
      // get the item VALUE for a previous flag
      //
      CurrentItemPackage->Value = ReallocatePool(ValueSize, ValueSize + StrSize(Argv[LoopCounter]) + sizeof(CHAR16), CurrentItemPackage->Value);
      ASSERT(CurrentItemPackage->Value != NULL);
      if (ValueSize == 0) {
        StrCpy(CurrentItemPackage->Value, Argv[LoopCounter]);
      } else {
        StrCat(CurrentItemPackage->Value, L" ");
        StrCat(CurrentItemPackage->Value, Argv[LoopCounter]);
      }
      ValueSize += StrSize(Argv[LoopCounter]) + sizeof(CHAR16);
      GetItemValue--;
      if (GetItemValue == 0) {
        InsertHeadList(*CheckPackage, &CurrentItemPackage->Link);
      }
    } else if (InternalIsFlag(Argv[LoopCounter], AlwaysAllowNumbers) == FALSE) {
      //
      // add this one as a non-flag
      //
      CurrentItemPackage = AllocatePool(sizeof(SHELL_PARAM_PACKAGE));
      ASSERT(CurrentItemPackage != NULL);
      CurrentItemPackage->Name  = NULL;
      CurrentItemPackage->Type  = TypePosition;
      CurrentItemPackage->Value = AllocatePool(StrSize(Argv[LoopCounter]));
      ASSERT(CurrentItemPackage->Value != NULL);
      StrCpy(CurrentItemPackage->Value, Argv[LoopCounter]);
      CurrentItemPackage->OriginalPosition = mTotalParameterCount++;
      InsertHeadList(*CheckPackage, &CurrentItemPackage->Link);
    } else if (ProblemParam) {
      //
      // this was a non-recognised flag... error!
      //
      *ProblemParam = AllocatePool(StrSize(Argv[LoopCounter]));
      ASSERT(*ProblemParam != NULL);
      StrCpy(*ProblemParam, Argv[LoopCounter]);
      ShellCommandLineFreeVarList(*CheckPackage);
      *CheckPackage = NULL;
      return (EFI_VOLUME_CORRUPTED);
    } else {
      ShellCommandLineFreeVarList(*CheckPackage);
      *CheckPackage = NULL;
      return (EFI_VOLUME_CORRUPTED);
    }
  }
  if (GetItemValue != 0) {
    GetItemValue = 0;
    InsertHeadList(*CheckPackage, &CurrentItemPackage->Link);
  }
  //
  // support for AutoPageBreak
  //
  if (AutoPageBreak && ShellCommandLineGetFlag(*CheckPackage, L"-b")) {
    ShellSetPageBreakMode(TRUE);
  }
  return (EFI_SUCCESS);
}

/**
  Checks the command line arguments passed against the list of valid ones.  
  Optionally removes NULL values first.
  
  If no initialization is required, then return RETURN_SUCCESS.
  
  @param CheckList              pointer to list of parameters to check
  @param CheckPackage           pointer to pointer to list checked values
  @param ProblemParam           optional pointer to pointer to unicode string for 
                                the paramater that caused failure.
  @param AutoPageBreak          will automatically set PageBreakEnabled for "b" parameter

  @retval EFI_SUCCESS           The operation completed sucessfully.
  @retval EFI_OUT_OF_RESOURCES  A memory allocation failed
  @retval EFI_INVALID_PARAMETER A parameter was invalid
  @retval EFI_VOLUME_CORRUPTED  the command line was corrupt.  an argument was 
                                duplicated.  the duplicated command line argument 
                                was returned in ProblemParam if provided.
  @retval EFI_DEVICE_ERROR      the commands contained 2 opposing arguments.  one
                                of the command line arguments was returned in 
                                ProblemParam if provided.
  @retval EFI_NOT_FOUND         a argument required a value that was missing.  
                                the invalid command line argument was returned in
                                ProblemParam if provided.
**/
EFI_STATUS
EFIAPI
ShellCommandLineParseEx (
  IN CONST SHELL_PARAM_ITEM     *CheckList,
  OUT LIST_ENTRY                **CheckPackage,
  OUT CHAR16                    **ProblemParam OPTIONAL,
  IN BOOLEAN                    AutoPageBreak,
  IN BOOLEAN                    AlwaysAllowNumbers
  ) {
  // 
  // ASSERT that CheckList and CheckPackage aren't NULL
  //
  ASSERT(CheckList    != NULL);
  ASSERT(CheckPackage != NULL);

  // 
  // Check for UEFI Shell 2.0 protocols
  //
  if (mEfiShellParametersProtocol != NULL) {
    return (InternalCommandLineParse(CheckList, 
                                     CheckPackage, 
                                     ProblemParam, 
                                     AutoPageBreak, 
                                     (CONST CHAR16**) mEfiShellParametersProtocol->Argv,
                                     mEfiShellParametersProtocol->Argc,
                                     AlwaysAllowNumbers));
  }

  // 
  // ASSERT That EFI Shell is not required
  //
  ASSERT (mEfiShellInterface != NULL);
  return (InternalCommandLineParse(CheckList, 
                                   CheckPackage, 
                                   ProblemParam, 
                                   AutoPageBreak, 
                                   (CONST CHAR16**) mEfiShellInterface->Argv,
                                   mEfiShellInterface->Argc,
                                   AlwaysAllowNumbers));
}

/**
  Frees shell variable list that was returned from ShellCommandLineParse.

  This function will free all the memory that was used for the CheckPackage
  list of postprocessed shell arguments.

  this function has no return value.

  if CheckPackage is NULL, then return

  @param CheckPackage           the list to de-allocate
  **/
VOID
EFIAPI
ShellCommandLineFreeVarList (
  IN LIST_ENTRY                 *CheckPackage
  ) {
  LIST_ENTRY                    *Node;

  //
  // check for CheckPackage == NULL
  //
  if (CheckPackage == NULL) {
    return;
  }

  //
  // for each node in the list
  //
  for ( Node = GetFirstNode(CheckPackage)
      ; IsListEmpty(CheckPackage) == FALSE
      ; Node = GetFirstNode(CheckPackage)
      ){
    //
    // Remove it from the list
    //
    RemoveEntryList(Node);

    //
    // if it has a name free the name
    //
    if (((SHELL_PARAM_PACKAGE*)Node)->Name != NULL) {
      FreePool(((SHELL_PARAM_PACKAGE*)Node)->Name);
    }

    //
    // if it has a value free the value
    //
    if (((SHELL_PARAM_PACKAGE*)Node)->Value != NULL) {
      FreePool(((SHELL_PARAM_PACKAGE*)Node)->Value);
    }
    
    //
    // free the node structure
    //
    FreePool((SHELL_PARAM_PACKAGE*)Node);
  }
  //
  // free the list head node
  //
  FreePool(CheckPackage);
}
/**
  Checks for presence of a flag parameter

  flag arguments are in the form of "-<Key>" or "/<Key>", but do not have a value following the key

  if CheckPackage is NULL then return FALSE.
  if KeyString is NULL then ASSERT()
  
  @param CheckPackage           The package of parsed command line arguments
  @param KeyString              the Key of the command line argument to check for

  @retval TRUE                  the flag is on the command line
  @retval FALSE                 the flag is not on the command line
  **/
BOOLEAN
EFIAPI
ShellCommandLineGetFlag (
  IN CONST LIST_ENTRY           *CheckPackage,
  IN CHAR16                     *KeyString
  ) {
  LIST_ENTRY                    *Node;

  //
  // ASSERT that both CheckPackage and KeyString aren't NULL
  //
  ASSERT(KeyString != NULL);

  //
  // return FALSE for no package
  //
  if (CheckPackage == NULL) {
    return (FALSE);
  }

  //
  // enumerate through the list of parametrs
  //
  for ( Node = GetFirstNode(CheckPackage) 
      ; !IsNull (CheckPackage, Node) 
      ; Node = GetNextNode(CheckPackage, Node) 
      ){
    //
    // If the Name matches, return TRUE (and there may be NULL name)
    //
    if (((SHELL_PARAM_PACKAGE*)Node)->Name != NULL) {
      //
      // If Type is TypeStart then only compare the begining of the strings
      //
      if ( ((SHELL_PARAM_PACKAGE*)Node)->Type == TypeStart 
        && StrnCmp(KeyString, ((SHELL_PARAM_PACKAGE*)Node)->Name, StrLen(KeyString)) == 0
        ){
        return (TRUE);
      } else if (StrCmp(KeyString, ((SHELL_PARAM_PACKAGE*)Node)->Name) == 0) {
        return (TRUE);
      }
    }
  }
  return (FALSE);
}
/**
  returns value from command line argument

  value parameters are in the form of "-<Key> value" or "/<Key> value"
  
  if CheckPackage is NULL, then return NULL;

  @param CheckPackage           The package of parsed command line arguments
  @param KeyString              the Key of the command line argument to check for

  @retval NULL                  the flag is not on the command line
  @return !=NULL                pointer to unicode string of the value
  **/
CONST CHAR16*
EFIAPI
ShellCommandLineGetValue (
  IN CONST LIST_ENTRY           *CheckPackage,
  IN CHAR16                     *KeyString
  ) {
  LIST_ENTRY                    *Node;

  //
  // check for CheckPackage == NULL
  //
  if (CheckPackage == NULL) {
    return (NULL);
  }

  //
  // enumerate through the list of parametrs
  //
  for ( Node = GetFirstNode(CheckPackage) 
      ; !IsNull (CheckPackage, Node) 
      ; Node = GetNextNode(CheckPackage, Node) 
      ){
    //
    // If the Name matches, return the value (name can be NULL)
    //
    if (((SHELL_PARAM_PACKAGE*)Node)->Name != NULL) {
      //
      // If Type is TypeStart then only compare the begining of the strings
      //
      if ( ((SHELL_PARAM_PACKAGE*)Node)->Type == TypeStart 
        && StrnCmp(KeyString, ((SHELL_PARAM_PACKAGE*)Node)->Name, StrLen(KeyString)) == 0
        ){
        //
        // return the string part after the flag
        //
        return (((SHELL_PARAM_PACKAGE*)Node)->Name + StrLen(KeyString));
      } else if (StrCmp(KeyString, ((SHELL_PARAM_PACKAGE*)Node)->Name) == 0) {
        //
        // return the value
        //
        return (((SHELL_PARAM_PACKAGE*)Node)->Value);
      }
    }
  }
  return (NULL);
}
/**
  returns raw value from command line argument

  raw value parameters are in the form of "value" in a specific position in the list
  
  if CheckPackage is NULL, then return NULL;

  @param CheckPackage           The package of parsed command line arguments
  @param Position               the position of the value 

  @retval NULL                  the flag is not on the command line
  @return !=NULL                pointer to unicode string of the value
  **/
CONST CHAR16*
EFIAPI
ShellCommandLineGetRawValue (
  IN CONST LIST_ENTRY           *CheckPackage,
  IN UINT32                     Position
  ) {
  LIST_ENTRY                    *Node;

  //
  // check for CheckPackage == NULL
  //
  if (CheckPackage == NULL) {
    return (NULL);
  }

  //
  // enumerate through the list of parametrs
  //
  for ( Node = GetFirstNode(CheckPackage) 
      ; !IsNull (CheckPackage, Node) 
      ; Node = GetNextNode(CheckPackage, Node) 
      ){
    //
    // If the position matches, return the value
    //
    if (((SHELL_PARAM_PACKAGE*)Node)->OriginalPosition == Position) {
      return (((SHELL_PARAM_PACKAGE*)Node)->Value);
    }
  }
  return (NULL);
}

/**
  returns the number of command line value parameters that were parsed.  
  
  this will not include flags.

  @retval (UINTN)-1     No parsing has ocurred
  @return other         The number of value parameters found
**/
UINTN
EFIAPI
ShellCommandLineGetCount(
  VOID
  )
{
  return (mTotalParameterCount);
}

/**
  Determins if a parameter is duplicated.

  If Param is not NULL then it will point to a callee allocated string buffer 
  with the parameter value if a duplicate is found.

  If CheckPackage is NULL, then ASSERT.

  @param[in] CheckPackage       The package of parsed command line arguments.
  @param[out] Param             Upon finding one, a pointer to the duplicated parameter.

  @retval EFI_SUCCESS           No parameters were duplicated.
  @retval EFI_DEVICE_ERROR      A duplicate was found.
  **/
EFI_STATUS
EFIAPI
ShellCommandLineCheckDuplicate (
  IN CONST LIST_ENTRY              *CheckPackage,
  OUT CHAR16                       **Param
  )
{
  LIST_ENTRY                    *Node1;
  LIST_ENTRY                    *Node2;
  
  ASSERT(CheckPackage != NULL);

  for ( Node1 = GetFirstNode(CheckPackage) 
      ; !IsNull (CheckPackage, Node1) 
      ; Node1 = GetNextNode(CheckPackage, Node1) 
      ){
    for ( Node2 = GetNextNode(CheckPackage, Node1) 
        ; !IsNull (CheckPackage, Node2) 
        ; Node2 = GetNextNode(CheckPackage, Node2) 
        ){
      if (StrCmp(((SHELL_PARAM_PACKAGE*)Node1)->Name, ((SHELL_PARAM_PACKAGE*)Node2)->Name) == 0) {
        if (Param != NULL) {
          *Param = NULL;
          *Param = StrnCatGrow(Param, NULL, ((SHELL_PARAM_PACKAGE*)Node1)->Name, 0);
        }
        return (EFI_DEVICE_ERROR);
      }
    }
  }
  return (EFI_SUCCESS);
}

/**
  This is a find and replace function.  it will return the NewString as a copy of 
  SourceString with each instance of FindTarget replaced with ReplaceWith.

  If the string would grow bigger than NewSize it will halt and return error.

  @param[in] SourceString             String with source buffer
  @param[in,out] NewString           String with resultant buffer
  @param[in] NewSize                  Size in bytes of NewString
  @param[in] FindTarget               String to look for
  @param[in[ ReplaceWith              String to replace FindTarget with

  @retval EFI_INVALID_PARAMETER       SourceString was NULL
  @retval EFI_INVALID_PARAMETER       NewString was NULL
  @retval EFI_INVALID_PARAMETER       FindTarget was NULL
  @retval EFI_INVALID_PARAMETER       ReplaceWith was NULL
  @retval EFI_INVALID_PARAMETER       FindTarget had length < 1
  @retval EFI_INVALID_PARAMETER       SourceString had length < 1
  @retval EFI_BUFFER_TOO_SMALL        NewSize was less than the minimum size to hold 
                                      the new string (truncation occurred)
  @retval EFI_SUCCESS                 the string was sucessfully copied with replacement
**/

EFI_STATUS
EFIAPI
CopyReplace(
  IN CHAR16 CONST                     *SourceString,
  IN CHAR16                           *NewString,
  IN UINTN                            NewSize,
  IN CONST CHAR16                     *FindTarget,
  IN CONST CHAR16                     *ReplaceWith
  ) 
{
  UINTN Size;
  if ( (SourceString == NULL)
    || (NewString    == NULL)
    || (FindTarget   == NULL)
    || (ReplaceWith  == NULL)
    || (StrLen(FindTarget) < 1)
    || (StrLen(SourceString) < 1)
    ){
    return (EFI_INVALID_PARAMETER);
  }
  NewString = SetMem16(NewString, NewSize, CHAR_NULL);
  while (*SourceString != CHAR_NULL) {
    if (StrnCmp(SourceString, FindTarget, StrLen(FindTarget)) == 0) {
      SourceString += StrLen(FindTarget);
      Size = StrSize(NewString);
      if ((Size + (StrLen(ReplaceWith)*sizeof(CHAR16))) > NewSize) {
        return (EFI_BUFFER_TOO_SMALL);
      }
      StrCat(NewString, ReplaceWith);
    } else {
      Size = StrSize(NewString);
      if (Size + sizeof(CHAR16) > NewSize) {
        return (EFI_BUFFER_TOO_SMALL);
      }
      StrnCat(NewString, SourceString, 1);
      SourceString++;
    }
  }
  return (EFI_SUCCESS);
}

/**
  Internal worker function to output a string.

  This function will output a string to the correct StdOut.

  @param[in] String       The string to print out.

  @retval EFI_SUCCESS     The operation was sucessful.
  @retval !EFI_SUCCESS    The operation failed.
**/
EFI_STATUS
EFIAPI
InternalPrintTo (
  IN CONST CHAR16 *String
  )
{
  UINTN Size;
  Size = StrSize(String) - sizeof(CHAR16);
  if (mEfiShellParametersProtocol != NULL) {
    return (mEfiShellParametersProtocol->StdOut->Write(mEfiShellParametersProtocol->StdOut, &Size, (VOID*)String));
  }
  if (mEfiShellInterface          != NULL) {
    return (         mEfiShellInterface->StdOut->Write(mEfiShellInterface->StdOut,          &Size, (VOID*)String));
  }
  ASSERT(FALSE);
  return (EFI_UNSUPPORTED);
}

/**
  Print at a specific location on the screen.

  This function will move the cursor to a given screen location and print the specified string
  
  If -1 is specified for either the Row or Col the current screen location for BOTH 
  will be used.

  if either Row or Col is out of range for the current console, then ASSERT
  if Format is NULL, then ASSERT

  In addition to the standard %-based flags as supported by UefiLib Print() this supports 
  the following additional flags:
    %N       -   Set output attribute to normal
    %H       -   Set output attribute to highlight
    %E       -   Set output attribute to error
    %B       -   Set output attribute to blue color
    %V       -   Set output attribute to green color

  Note: The background color is controlled by the shell command cls.

  @param[in] Row        the row to print at
  @param[in] Col        the column to print at
  @param[in] Format     the format string
  @param[in] Marker     the marker for the variable argument list

  @return the number of characters printed to the screen
**/

UINTN
EFIAPI
InternalShellPrintWorker(
  IN INT32                Col OPTIONAL,
  IN INT32                Row OPTIONAL,
  IN CONST CHAR16         *Format,
  VA_LIST                 Marker
  ) 
{
  UINTN             BufferSize;
  CHAR16            *PostReplaceFormat;
  CHAR16            *PostReplaceFormat2;
  UINTN             Return;
  EFI_STATUS        Status;
  UINTN             NormalAttribute;
  CHAR16            *ResumeLocation;
  CHAR16            *FormatWalker;
  
  BufferSize = PcdGet16 (PcdShellLibMaxPrintBufferSize);
  ASSERT(PcdGet16 (PcdShellLibMaxPrintBufferSize) < PcdGet32 (PcdMaximumUnicodeStringLength));
  PostReplaceFormat = AllocateZeroPool (BufferSize);
  ASSERT (PostReplaceFormat != NULL);
  PostReplaceFormat2 = AllocateZeroPool (BufferSize);
  ASSERT (PostReplaceFormat2 != NULL);

  //
  // Back and forth each time fixing up 1 of our flags...
  //
  Status = CopyReplace(Format,             PostReplaceFormat,  BufferSize, L"%N", L"%%N");
  ASSERT_EFI_ERROR(Status);
  Status = CopyReplace(PostReplaceFormat,  PostReplaceFormat2, BufferSize, L"%E", L"%%E");
  ASSERT_EFI_ERROR(Status);
  Status = CopyReplace(PostReplaceFormat2, PostReplaceFormat,  BufferSize, L"%H", L"%%H");
  ASSERT_EFI_ERROR(Status);
  Status = CopyReplace(PostReplaceFormat,  PostReplaceFormat2, BufferSize, L"%B", L"%%B");
  ASSERT_EFI_ERROR(Status);
  Status = CopyReplace(PostReplaceFormat2, PostReplaceFormat,  BufferSize, L"%V", L"%%V");
  ASSERT_EFI_ERROR(Status);

  //
  // Use the last buffer from replacing to print from...
  //
  Return = UnicodeVSPrint (PostReplaceFormat2, BufferSize, PostReplaceFormat, Marker);

  FreePool(PostReplaceFormat);

  if (Col != -1 && Row != -1) {
    Status = gST->ConOut->SetCursorPosition(gST->ConOut, Col, Row);
    ASSERT_EFI_ERROR(Status);
  }

  NormalAttribute = gST->ConOut->Mode->Attribute;
  FormatWalker = PostReplaceFormat2;
  while (*FormatWalker != CHAR_NULL) {
    //
    // Find the next attribute change request
    //
    ResumeLocation = StrStr(FormatWalker, L"%");
    if (ResumeLocation != NULL) {
      *ResumeLocation = CHAR_NULL;
    }
    //
    // print the current FormatWalker string
    //
    Status = InternalPrintTo(FormatWalker);
    ASSERT_EFI_ERROR(Status);
    //
    // update the attribute
    //
    if (ResumeLocation != NULL) {
      switch (*(ResumeLocation+1)) {
        case (L'N'):
          gST->ConOut->SetAttribute(gST->ConOut, NormalAttribute);
          break;
        case (L'E'):
          gST->ConOut->SetAttribute(gST->ConOut, EFI_TEXT_ATTR(EFI_YELLOW, ((NormalAttribute&(BIT4|BIT5|BIT6))>>4)));
          break;
        case (L'H'):
          gST->ConOut->SetAttribute(gST->ConOut, EFI_TEXT_ATTR(EFI_WHITE, ((NormalAttribute&(BIT4|BIT5|BIT6))>>4)));
          break;
        case (L'B'):
          gST->ConOut->SetAttribute(gST->ConOut, EFI_TEXT_ATTR(EFI_BLUE, ((NormalAttribute&(BIT4|BIT5|BIT6))>>4)));
          break;
        case (L'V'):
          gST->ConOut->SetAttribute(gST->ConOut, EFI_TEXT_ATTR(EFI_GREEN, ((NormalAttribute&(BIT4|BIT5|BIT6))>>4)));
          break;
        default:
          //
          // Print a simple '%' symbol
          //
          Status = InternalPrintTo(L"%");
          ASSERT_EFI_ERROR(Status);
          ResumeLocation = ResumeLocation - 1;
          break;
      }
    } else {
      //
      // reset to normal now...
      //
      gST->ConOut->SetAttribute(gST->ConOut, NormalAttribute);
      break;
    }

    //
    // update FormatWalker to Resume + 2 (skip the % and the indicator)
    //
    FormatWalker = ResumeLocation + 2;
  }

  FreePool(PostReplaceFormat2);

  return (Return);
}

/**
  Print at a specific location on the screen.

  This function will move the cursor to a given screen location and print the specified string.
  
  If -1 is specified for either the Row or Col the current screen location for BOTH 
  will be used.

  If either Row or Col is out of range for the current console, then ASSERT.
  If Format is NULL, then ASSERT.

  In addition to the standard %-based flags as supported by UefiLib Print() this supports 
  the following additional flags:
    %N       -   Set output attribute to normal
    %H       -   Set output attribute to highlight
    %E       -   Set output attribute to error
    %B       -   Set output attribute to blue color
    %V       -   Set output attribute to green color

  Note: The background color is controlled by the shell command cls.

  @param[in] Row        the row to print at
  @param[in] Col        the column to print at
  @param[in] Format     the format string

  @return the number of characters printed to the screen
**/

UINTN
EFIAPI
ShellPrintEx(
  IN INT32                Col OPTIONAL,
  IN INT32                Row OPTIONAL,
  IN CONST CHAR16         *Format,
  ...
  ) 
{
  VA_LIST           Marker;
  EFI_STATUS        Status;
  VA_START (Marker, Format);
  Status = InternalShellPrintWorker(Col, Row, Format, Marker);
  VA_END(Marker);
  return(Status);
}

/**
  Print at a specific location on the screen.

  This function will move the cursor to a given screen location and print the specified string.
  
  If -1 is specified for either the Row or Col the current screen location for BOTH 
  will be used.

  If either Row or Col is out of range for the current console, then ASSERT.
  If Format is NULL, then ASSERT.

  In addition to the standard %-based flags as supported by UefiLib Print() this supports 
  the following additional flags:
    %N       -   Set output attribute to normal
    %H       -   Set output attribute to highlight
    %E       -   Set output attribute to error
    %B       -   Set output attribute to blue color
    %V       -   Set output attribute to green color

  Note: The background color is controlled by the shell command cls.

  @param[in] Row                the row to print at
  @param[in] Col                the column to print at
  @param[in] HiiFormatStringId  the format string Id for getting from Hii
  @param[in] HiiFormatHandle    the format string Handle for getting from Hii

  @return the number of characters printed to the screen
**/
UINTN
EFIAPI
ShellPrintHiiEx(
  IN INT32                Col OPTIONAL,
  IN INT32                Row OPTIONAL,
  IN CONST EFI_STRING_ID  HiiFormatStringId,
  IN CONST EFI_HANDLE     HiiFormatHandle,
  ...
  )
{
  VA_LIST           Marker;
  CHAR16            *HiiFormatString;
  UINTN             RetVal;

  VA_START (Marker, HiiFormatHandle);
  HiiFormatString = HiiGetString(HiiFormatHandle, HiiFormatStringId, NULL);
  ASSERT(HiiFormatString != NULL);

  RetVal = InternalShellPrintWorker(Col, Row, HiiFormatString, Marker);

  FreePool(HiiFormatString);
  VA_END(Marker);

  return (RetVal);
}

/**
  Function to determine if a given filename represents a file or a directory.

  @param[in] DirName      Path to directory to test.

  @retval EFI_SUCCESS     The Path represents a directory
  @retval EFI_NOT_FOUND   The Path does not represent a directory
  @return other           The path failed to open
**/
EFI_STATUS
EFIAPI
ShellIsDirectory(
  IN CONST CHAR16 *DirName
  )
{
  EFI_STATUS        Status;
  EFI_FILE_HANDLE   Handle;

  Handle = NULL;

  Status = ShellOpenFileByName(DirName, &Handle, EFI_FILE_MODE_READ, 0);
  if (EFI_ERROR(Status)) {
    return (Status);
  }

  if (FileHandleIsDirectory(Handle) == EFI_SUCCESS) {
    ShellCloseFile(&Handle);
    return (EFI_SUCCESS);
  }
  ShellCloseFile(&Handle);
  return (EFI_NOT_FOUND);
}

/**
  Function to determine if a given filename represents a file.

  @param[in] Name         Path to file to test.

  @retval EFI_SUCCESS     The Path represents a file.
  @retval EFI_NOT_FOUND   The Path does not represent a file.
  @retval other           The path failed to open.
**/
EFI_STATUS
EFIAPI
ShellIsFile(
  IN CONST CHAR16 *Name
  )
{
  EFI_STATUS        Status;
  EFI_FILE_HANDLE   Handle;

  Handle = NULL;

  Status = ShellOpenFileByName(Name, &Handle, EFI_FILE_MODE_READ, 0);
  if (EFI_ERROR(Status)) {
    return (Status);
  }

  if (FileHandleIsDirectory(Handle) != EFI_SUCCESS) {
    ShellCloseFile(&Handle);
    return (EFI_SUCCESS);
  }
  ShellCloseFile(&Handle);
  return (EFI_NOT_FOUND);
}

/**
  Function to determine whether a string is decimal or hex representation of a number 
  and return the number converted from the string.

  @param[in] String   String representation of a number

  @retval all         the number
**/
UINTN
EFIAPI
ShellStrToUintn(
  IN CONST CHAR16 *String
  )
{
  CONST CHAR16  *Walker;
  for (Walker = String; Walker != NULL && *Walker != CHAR_NULL && *Walker == L' '; Walker = Walker + 1);
  if (StrnCmp(Walker, L"0x", 2) == 0 || StrnCmp(Walker, L"0X", 2) == 0){
    return (StrHexToUintn(Walker));
  }
  return (StrDecimalToUintn(Walker));
}

/**
  Safely append with automatic string resizing given length of Destination and
  desired length of copy from Source.

  append the first D characters of Source to the end of Destination, where D is
  the lesser of Count and the StrLen() of Source. If appending those D characters
  will fit within Destination (whose Size is given as CurrentSize) and
  still leave room for a null terminator, then those characters are appended,
  starting at the original terminating null of Destination, and a new terminating
  null is appended.

  If appending D characters onto Destination will result in a overflow of the size
  given in CurrentSize the string will be grown such that the copy can be performed
  and CurrentSize will be updated to the new size.

  If Source is NULL, there is nothing to append, just return the current buffer in
  Destination.

  if Destination is NULL, then ASSERT()
  if Destination's current length (including NULL terminator) is already more then
  CurrentSize, then ASSERT()

  @param[in,out] Destination   The String to append onto
  @param[in,out] CurrentSize   on call the number of bytes in Destination.  On
                                return possibly the new size (still in bytes).  if NULL
                                then allocate whatever is needed.
  @param[in]      Source        The String to append from
  @param[in]      Count         Maximum number of characters to append.  if 0 then
                                all are appended.

  @return Destination           return the resultant string.
**/
CHAR16*
EFIAPI
StrnCatGrow (
  IN OUT CHAR16           **Destination,
  IN OUT UINTN            *CurrentSize,
  IN     CONST CHAR16     *Source,
  IN     UINTN            Count
  )
{
  UINTN DestinationStartSize;
  UINTN NewSize;

  //
  // ASSERTs
  //
  ASSERT(Destination != NULL);

  //
  // If there's nothing to do then just return Destination
  //
  if (Source == NULL) {
    return (*Destination);
  }

  //
  // allow for un-initialized pointers, based on size being 0
  //
  if (CurrentSize != NULL && *CurrentSize == 0) {
    *Destination = NULL;
  }

  //
  // allow for NULL pointers address as Destination
  //
  if (*Destination != NULL) {
    ASSERT(CurrentSize != 0);
    DestinationStartSize = StrSize(*Destination);
    ASSERT(DestinationStartSize <= *CurrentSize);
  } else {
    DestinationStartSize = 0;
//    ASSERT(*CurrentSize == 0);
  }

  //
  // Append all of Source?
  //
  if (Count == 0) {
    Count = StrLen(Source);
  }

  //
  // Test and grow if required
  //
  if (CurrentSize != NULL) {
    NewSize = *CurrentSize;
    while (NewSize < (DestinationStartSize + (Count*sizeof(CHAR16)))) {
      NewSize += 2 * Count * sizeof(CHAR16);
    }
    *Destination = ReallocatePool(*CurrentSize, NewSize, *Destination);
    *CurrentSize = NewSize;
  } else {
    *Destination = AllocateZeroPool((Count+1)*sizeof(CHAR16));
  }

  //
  // Now use standard StrnCat on a big enough buffer
  //
  return StrnCat(*Destination, Source, Count);
}