91 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			91 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|  | /* Xz.c - Xz
 | ||
|  | 2017-05-12 : Igor Pavlov : Public domain */ | ||
|  | 
 | ||
|  | #include "Precomp.h"
 | ||
|  | 
 | ||
|  | #include "7zCrc.h"
 | ||
|  | #include "CpuArch.h"
 | ||
|  | #include "Xz.h"
 | ||
|  | #include "XzCrc64.h"
 | ||
|  | 
 | ||
|  | const Byte XZ_SIG[XZ_SIG_SIZE] = { 0xFD, '7', 'z', 'X', 'Z', 0 }; | ||
|  | /* const Byte XZ_FOOTER_SIG[XZ_FOOTER_SIG_SIZE] = { 'Y', 'Z' }; */ | ||
|  | 
 | ||
|  | unsigned Xz_WriteVarInt(Byte *buf, UInt64 v) | ||
|  | { | ||
|  |   unsigned i = 0; | ||
|  |   do | ||
|  |   { | ||
|  |     buf[i++] = (Byte)((v & 0x7F) | 0x80); | ||
|  |     v >>= 7; | ||
|  |   } | ||
|  |   while (v != 0); | ||
|  |   buf[(size_t)i - 1] &= 0x7F; | ||
|  |   return i; | ||
|  | } | ||
|  | 
 | ||
|  | void Xz_Construct(CXzStream *p) | ||
|  | { | ||
|  |   p->numBlocks = 0; | ||
|  |   p->blocks = NULL; | ||
|  |   p->flags = 0; | ||
|  | } | ||
|  | 
 | ||
|  | void Xz_Free(CXzStream *p, ISzAllocPtr alloc) | ||
|  | { | ||
|  |   ISzAlloc_Free(alloc, p->blocks); | ||
|  |   p->numBlocks = 0; | ||
|  |   p->blocks = NULL; | ||
|  | } | ||
|  | 
 | ||
|  | unsigned XzFlags_GetCheckSize(CXzStreamFlags f) | ||
|  | { | ||
|  |   unsigned t = XzFlags_GetCheckType(f); | ||
|  |   return (t == 0) ? 0 : (4 << ((t - 1) / 3)); | ||
|  | } | ||
|  | 
 | ||
|  | void XzCheck_Init(CXzCheck *p, unsigned mode) | ||
|  | { | ||
|  |   p->mode = mode; | ||
|  |   switch (mode) | ||
|  |   { | ||
|  |     case XZ_CHECK_CRC32: p->crc = CRC_INIT_VAL; break; | ||
|  |     case XZ_CHECK_CRC64: p->crc64 = CRC64_INIT_VAL; break; | ||
|  |     case XZ_CHECK_SHA256: Sha256_Init(&p->sha); break; | ||
|  |   } | ||
|  | } | ||
|  | 
 | ||
|  | void XzCheck_Update(CXzCheck *p, const void *data, size_t size) | ||
|  | { | ||
|  |   switch (p->mode) | ||
|  |   { | ||
|  |     case XZ_CHECK_CRC32: p->crc = CrcUpdate(p->crc, data, size); break; | ||
|  |     case XZ_CHECK_CRC64: p->crc64 = Crc64Update(p->crc64, data, size); break; | ||
|  |     case XZ_CHECK_SHA256: Sha256_Update(&p->sha, (const Byte *)data, size); break; | ||
|  |   } | ||
|  | } | ||
|  | 
 | ||
|  | int XzCheck_Final(CXzCheck *p, Byte *digest) | ||
|  | { | ||
|  |   switch (p->mode) | ||
|  |   { | ||
|  |     case XZ_CHECK_CRC32: | ||
|  |       SetUi32(digest, CRC_GET_DIGEST(p->crc)); | ||
|  |       break; | ||
|  |     case XZ_CHECK_CRC64: | ||
|  |     { | ||
|  |       int i; | ||
|  |       UInt64 v = CRC64_GET_DIGEST(p->crc64); | ||
|  |       for (i = 0; i < 8; i++, v >>= 8) | ||
|  |         digest[i] = (Byte)(v & 0xFF); | ||
|  |       break; | ||
|  |     } | ||
|  |     case XZ_CHECK_SHA256: | ||
|  |       Sha256_Final(&p->sha, digest); | ||
|  |       break; | ||
|  |     default: | ||
|  |       return 0; | ||
|  |   } | ||
|  |   return 1; | ||
|  | } |