1 /* Xz.c - Xz
2 2009-04-15 : Igor Pavlov : Public domain */
3
4 #include "7zCrc.h"
5 #include "CpuArch.h"
6 #include "Xz.h"
7 #include "XzCrc64.h"
8
9 Byte XZ_SIG[XZ_SIG_SIZE] = { 0xFD, '7', 'z', 'X', 'Z', 0 };
10 Byte XZ_FOOTER_SIG[XZ_FOOTER_SIG_SIZE] = { 'Y', 'Z' };
11
Xz_WriteVarInt(Byte * buf,UInt64 v)12 unsigned Xz_WriteVarInt(Byte *buf, UInt64 v)
13 {
14 unsigned i = 0;
15 do
16 {
17 buf[i++] = (Byte)((v & 0x7F) | 0x80);
18 v >>= 7;
19 }
20 while (v != 0);
21 buf[i - 1] &= 0x7F;
22 return i;
23 }
24
Xz_Construct(CXzStream * p)25 void Xz_Construct(CXzStream *p)
26 {
27 p->numBlocks = p->numBlocksAllocated = 0;
28 p->blocks = 0;
29 p->flags = 0;
30 }
31
Xz_Free(CXzStream * p,ISzAlloc * alloc)32 void Xz_Free(CXzStream *p, ISzAlloc *alloc)
33 {
34 alloc->Free(alloc, p->blocks);
35 p->numBlocks = p->numBlocksAllocated = 0;
36 p->blocks = 0;
37 }
38
XzFlags_GetCheckSize(CXzStreamFlags f)39 unsigned XzFlags_GetCheckSize(CXzStreamFlags f)
40 {
41 int t = XzFlags_GetCheckType(f);
42 return (t == 0) ? 0 : (4 << ((t - 1) / 3));
43 }
44
XzCheck_Init(CXzCheck * p,int mode)45 void XzCheck_Init(CXzCheck *p, int mode)
46 {
47 p->mode = mode;
48 switch (mode)
49 {
50 case XZ_CHECK_CRC32: p->crc = CRC_INIT_VAL; break;
51 case XZ_CHECK_CRC64: p->crc64 = CRC64_INIT_VAL; break;
52 case XZ_CHECK_SHA256: Sha256_Init(&p->sha); break;
53 }
54 }
55
XzCheck_Update(CXzCheck * p,const void * data,size_t size)56 void XzCheck_Update(CXzCheck *p, const void *data, size_t size)
57 {
58 switch (p->mode)
59 {
60 case XZ_CHECK_CRC32: p->crc = CrcUpdate(p->crc, data, size); break;
61 case XZ_CHECK_CRC64: p->crc64 = Crc64Update(p->crc64, data, size); break;
62 case XZ_CHECK_SHA256: Sha256_Update(&p->sha, (const Byte *)data, size); break;
63 }
64 }
65
XzCheck_Final(CXzCheck * p,Byte * digest)66 int XzCheck_Final(CXzCheck *p, Byte *digest)
67 {
68 switch (p->mode)
69 {
70 case XZ_CHECK_CRC32:
71 SetUi32(digest, CRC_GET_DIGEST(p->crc));
72 break;
73 case XZ_CHECK_CRC64:
74 {
75 int i;
76 UInt64 v = CRC64_GET_DIGEST(p->crc64);
77 for (i = 0; i < 8; i++, v >>= 8)
78 digest[i] = (Byte)(v & 0xFF);
79 break;
80 }
81 case XZ_CHECK_SHA256:
82 Sha256_Final(&p->sha, digest);
83 break;
84 default:
85 return 0;
86 }
87 return 1;
88 }
89