litezip.c

来自「是一个C语言的压缩和解压缩的DLL源程序.」· C语言 代码 · 共 1,988 行 · 第 1/5 页

	char		*password;		// A copy of the password from the application.
	DWORD		writ;			// How many bytes we've written to destination. This is maintained by addSrc(), not
								// writeDestination(), to avoid confusion over seeks.
	DWORD		ooffset;		// The initial offset where we start writing the zip within destination. (This allows
								// the app to write the zip to an already open file that has data in it).
	DWORD		lasterr;		// The last error code.

	// Memory map stuff
	HANDLE		memorymap;		// If not 0, then this is a memory mapped file handle.
	DWORD		opos;			// Current (byte) position in "destination".
	DWORD		mapsize;		// The size of the memory buffer.

	// Encryption
	unsigned long keys[3];		// keys are initialised inside addSrc()
	char		*encbuf;		// If encrypting, then this is a temporary workspace for encrypting the data (to
	unsigned int encbufsize;	// be used and resized inside writeDestination(), and deleted when the TZIP is freed)

	TZIPFILEINFO	*zfis;		// Each file gets added onto this list, for writing the table at the end

	// ====================================================================
	// These variables are for the source (that supplies the data to be added to the ZIP)
	DWORD		isize, totalRead;	// size is not set until close() on pipes
	ULG			crc;				// crc is not set until close(). iwrit is cumulative
	HANDLE		source;
	DWORD		lenin, posin;		// These are for a memory buffer source
	// and a variable for what we've done with the input: (i.e. compressed it!)
	ULG			csize;				// Compressed size, set by the compression routines.
	TSTATE		*state;				// We allocate just one state object per zip, because it's big (500k), and store a ptr here. It is freed when the TZIP is freed
	char		buf[16384];			// Used by some of the compression routines. This must be last!!
} TZIP;












// ========================== DATA ============================

// NOTE: I specify this data section to be Shared (ie, each running rexx
// script shares these variables, rather than getting its own copies of these
// variables). This is because, since I have only globals that are read-only
// or whose value is the same for all processes, I don't need a separate copy
// of these for each process that uses this DLL. In Visual C++'s Linker
// settings, I add "/section:Shared,rws"

#pragma data_seg("shared")

static HINSTANCE	ThisInstance;

static const int Extra_lbits[LENGTH_CODES] // extra bits for each length code
   = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};

static const int Extra_dbits[D_CODES] // extra bits for each distance code
   = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};

static const int Extra_blbits[BL_CODES]// extra bits for each bit length code
   = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};

// Values for max_lazy_match, good_match, nice_match and max_chain_length,
// depending on the desired pack level (0..9). The values given below have
// been tuned to exclude worst case performance for pathological files.
// Better values may be found for specific files.
//

static const CONFIG ConfigurationTable[10] = {
	//  good lazy nice chain
	{0,    0,  0,    0},  // 0 store only
	{4,    4,  8,    4},  // 1 maximum speed, no lazy matches
	{4,    5, 16,    8},  // 2
	{4,    6, 32,   32},  // 3
	{4,    4, 16,   16},  // 4 lazy matches */
	{8,   16, 32,   32},  // 5
	{8,   16, 128, 128},  // 6
	{8,   32, 128, 256},  // 7
	{32, 128, 258, 1024}, // 8
	{32, 258, 258, 4096}};// 9 maximum compression */

// Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
// For deflate_fast() (levels <= 3) good is ignored and lazy has a different meaning.

static const ULG CrcTable[256] = {
  0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
  0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
  0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
  0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
  0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
  0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
  0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
  0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
  0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
  0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
  0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
  0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
  0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
  0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
  0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
  0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
  0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
  0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
  0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
  0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
  0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
  0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
  0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
  0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
  0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
  0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
  0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
  0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
  0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
  0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
  0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
  0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
  0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
  0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
  0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
  0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
  0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
  0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
  0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
  0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
  0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
  0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
  0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
  0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
  0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
  0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
  0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
  0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
  0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
  0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
  0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
  0x2d02ef8dL
};

static const char ZipSuffixes[] = {".z\0"
".zip\0"
".zoo\0"
".arc\0"
".lzh\0"
".arj\0"
".gz\0"
".tgz\0"};

// The lengths of the bit length codes are sent in order of decreasing
// probability, to avoid transmitting the lengths for unused bit length codes.
static const UCH BL_order[BL_CODES] = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};

#pragma data_seg()


















// ====================== LOCAL DECLARATIONS =======================

static void			writeDestShort(TZIP *, DWORD);
static void			writeDestination(TZIP *, const char *, DWORD);
static unsigned		readFromSource(register TZIP *, char *buf, unsigned size);
static void			pqdownheap(register TSTATE *, CT_DATA *, int);
static void			gen_codes(register TSTATE *, CT_DATA *, int);
static void			compress_block(register TSTATE *, CT_DATA *, CT_DATA *);
static BOOL			send_bits(register TSTATE *, int, int);
static unsigned		bi_reverse(register unsigned, register unsigned char);
static void			bi_windup(register TSTATE *);
static void			copy_block(register TSTATE *, char *, DWORD, DWORD);
static void			fill_window(register TSTATE *);






















// ==================== Unix/Windows Time conversion ====================

void filetime2dosdatetime(const FILETIME ft, WORD *dosdate,WORD *dostime)
{
	// date: bits 0-4 are day of month 1-31. Bits 5-8 are month 1..12. Bits 9-15 are year-1980
	// time: bits 0-4 are seconds/2, bits 5-10 are minute 0..59. Bits 11-15 are hour 0..23
	SYSTEMTIME st;
	
	FileTimeToSystemTime(&ft, &st);
	*dosdate = (WORD)(((st.wYear-1980) & 0x7f) << 9);
	*dosdate |= (WORD)((st.wMonth&0xf) << 5);
	*dosdate |= (WORD)((st.wDay&0x1f));
	*dostime = (WORD)((st.wHour&0x1f) << 11);
	*dostime |= (WORD)((st.wMinute&0x3f) << 5);
	*dostime |= (WORD)((st.wSecond*2)&0x1f);
}

lutime_t filetime2timet(const FILETIME ft)
{
	LONGLONG i;

	i = *(LONGLONG*)&ft; 
	return (lutime_t)((i - 116444736000000000)/10000000);
}

static void getNow(lutime_t *pft, WORD *dosdate, WORD *dostime)
{
	SYSTEMTIME	st;
	FILETIME	ft;
	
	GetLocalTime(&st);
	SystemTimeToFileTime(&st, &ft);
	filetime2dosdatetime(ft, dosdate, dostime);
	*pft = filetime2timet(ft);
}

static DWORD getFilePos(HANDLE hfout)
{
	return(SetFilePointer(hfout, 0, 0, FILE_CURRENT));
}



/********************* getFileInfo() ***********************
 * Retrieves the attributes, size, and timestamps (in ZIP
 * format) from the file handle.
 */

static DWORD getFileInfo(TZIP *tzip, IZTIMES *times)
{
	BY_HANDLE_FILE_INFORMATION	bhi;
	ULG							a;

	// The date and time is returned in a long with the date most significant to allow
	// unsigned integer comparison of absolute times. The attributes have two
	// high bytes unix attr, and two low bytes a mapping of that to DOS attr.

	// struct stat s; int res=stat(fn,&s); if (res!=0) return false;
	// translate windows file attributes into zip ones.
	if (!GetFileInformationByHandle(tzip->source, &bhi)) return(ZR_NOFILE);

	a = 0;

	// Zip uses the lower word for its interpretation of windows stuff
	if (bhi.dwFileAttributes & FILE_ATTRIBUTE_READONLY) a |= 0x01;
	if (bhi.dwFileAttributes & FILE_ATTRIBUTE_HIDDEN) a |= 0x02;
	if (bhi.dwFileAttributes & FILE_ATTRIBUTE_SYSTEM) a |= 0x04;
	if (bhi.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) a |= 0x10;
	if (bhi.dwFileAttributes & FILE_ATTRIBUTE_ARCHIVE) a |= 0x20;
	// It uses the upper word for standard unix attr, which we manually construct
	if (bhi.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
		a |= 0x40000000;	// directory
	else
		a |= 0x80000000;	// normal file
	a |= 0x01000000;		// readable
	if (!(bhi.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
		a |= 0x00800000;	// writeable

	// Check if it's an executable
	if ((tzip->isize = GetFileSize(tzip->source, 0)) > 40 && !tzip->ooffset)
	{
		DWORD			read;
		unsigned short	magic;
		unsigned long	hpos;

		SetFilePointer(tzip->source, 0, 0, FILE_BEGIN);
		ReadFile(tzip->source, &magic, sizeof(magic), &read, 0);
		SetFilePointer(tzip->source, 36, 0, FILE_BEGIN);
		ReadFile(tzip->source, &hpos, sizeof(hpos), &read, 0);
		if (magic == 0x54AD && tzip->isize > hpos+4+20+28)
		{
			unsigned long signature;

			SetFilePointer(tzip->source, hpos, 0, FILE_BEGIN);
			ReadFile(tzip->source, &signature, sizeof(signature), &read, 0);
			if (signature == IMAGE_DOS_SIGNATURE || signature == IMAGE_OS2_SIGNATURE || signature == IMAGE_OS2_SIGNATURE_LE || signature == IMAGE_NT_SIGNATURE)
				a |= 0x00400000; // executable
		}

		// Reset file pointer back to where it initially was
		SetFilePointer(tzip->source, 0, 0, FILE_BEGIN);
	}

	times->attributes = a;

	// lutime_t is 32bit number of seconds elapsed since 0:0:0GMT, Jan1, 1970.
	// but FILETIME is 64bit number of 100-nanosecs since Jan1, 1601
	times->atime = filetime2timet(bhi.ftLastAccessTime);
	times->mtime = filetime2timet(bhi.ftLastWriteTime);
	times->ctime = filetime2timet(bhi.ftCreationTime);

	{
	WORD	dosdate,dostime;

	filetime2dosdatetime(bhi.ftLastWriteTime, &dosdate, &dostime);
	times->timestamp = (WORD)dostime | (((DWORD)dosdate)<<16);
	}

	return(ZR_OK);
}









// ==================== DEBUG STUFF ====================

#ifndef NDEBUG
static void Assert(TSTATE *state, BOOL cond, const char *msg)
{
	if (!cond) state->err = msg;
}

static void Trace(const char *x, ...)
{
	va_list paramList;
	va_start(paramList, x);
	paramList;
	va_end(paramList);
}
#endif








// =================== Low level compression ==================

// Send a code of the given tree. c and tree must not have side effects
#define send_code(state, c, tree) send_bits(state, tree[c].fc.code, tree[c].dl.len)

// Mapping from a distance to a distance code. dist is the distance - 1 and
// must not have side effects. dist_code[256] and dist_code[257] are never used.
#define d_code(dist) ((dist) < 256 ? state->ts.dist_code[dist] : state->ts.dist_code[256+((dist)>>7)])

// the arguments must not have side effects
#define Max(a,b) (a >= b ? a : b)





/********************* init_block() *********************
 * Initializes a new block.
 */

static void init_block(register TSTATE *state)
{
    int n; // iterates over tree elements

    // Initialize the trees
    for (n = 0; n < L_CODES;  n++) state->ts.dyn_ltree[n].fc.freq = 0;
    for (n = 0; n < D_CODES;  n++) state->ts.dyn_dtree[n].fc.freq = 0;
    for (n = 0; n < BL_CODES; n++) state->ts.bl_tree[n].fc.freq = 0;

    state->ts.dyn_ltree[END_BLOCK].fc.freq = 1;
    state->ts.opt_len = state->ts.static_len = 0;
    state->ts.last_lit = state->ts.last_dist = state->ts.last_flags = 0;
    state->ts.flags = 0; state->ts.flag_bit = 1;
}