windows-nt/Source/XPSP1/NT/sdktools/link16/pack.c

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2020-09-26 03:20:57 -05:00
/*static char *SCCSID = "%W% %E%";*/
/*
* Copyright Microsoft Corporation 1983-1987
*
* This Module contains Proprietary Information of Microsoft
* Corporation and should be treated as Confidential.
*/
/* Exepack */
/****************************************************************
* *
* PACK.C *
* *
****************************************************************/
#include <minlit.h> /* Types, constants */
#include <bndtrn.h> /* More types and constants */
#include <bndrel.h> /* More types and constants */
#include <lnkio.h> /* Linker I/O definitions */
#include <lnkmsg.h> /* Error messages */
#include <extern.h> /* External declarations */
#if FEXEPACK AND ODOS3EXE /* Whole file is conditional */
typedef struct _RUNTYPE
{
WORD wSignature;
WORD cbLastp;
WORD cpnRes;
WORD irleMax;
WORD cparDirectory;
WORD cparMinAlloc;
WORD cparMaxAlloc;
WORD saStack;
WORD raStackInit;
WORD wchksum;
WORD raStart;
WORD saStart;
WORD rbrgrle;
WORD iovMax;
WORD doslev;
}
RUNTYPE;
/* States of automaton */
#define STARTSTATE 0
#define FINDREPEAT 1
#define FINDENDRPT 2
#define EMITRECORD 3
/*
* LOCAL FUNCTION PROTOTYPES
*/
LOCAL void NEAR EmitRecords(void);
LOCAL unsigned char NEAR GetFromVM(void);
LOCAL unsigned short NEAR ScanWhileSame(void);
LOCAL unsigned short NEAR ScanWhileDifferent(void);
LOCAL WORD NEAR AfterScanning(unsigned short l);
LOCAL void NEAR OutEnum(void);
LOCAL void NEAR OutIter(SATYPE sa, WORD length);
/*
* DATA DEFINED IN UNPACK MODULE: unpack.asm
*/
#if NOT defined( _WIN32 )
extern char * FAR cdecl UnpackModule; /* Unpacker/Relocator module */
extern char FAR cdecl SegStart; // Start of unpacker
extern WORD FAR cdecl cbUnpack; /* Length of UnpackModule */
extern WORD FAR cdecl ipsave; /* Original IP */
extern WORD FAR cdecl cssave; /* Original CS */
extern WORD FAR cdecl spsave; /* Original SP */
extern WORD FAR cdecl sssave; /* Original SS */
extern WORD FAR cdecl cparExp; /* # para. in expanded image */
extern WORD FAR cdecl raStartUnpack; /* Offset of code start in unpacker */
extern WORD FAR cdecl raMoveUnpack; /* Offset of self-moving in unpacker */
extern WORD FAR cdecl raBadStack; /* Bottom of bad stack range */
extern WORD FAR cdecl szBadStack; /* Bad stack range */
#else // _WIN32
//
// For the portable NTGroup version of this linker, we can't use unpack32.asm
// directly because we need to run on RISC platforms. But we still need this
// code, which is real-mode x86 code tacked onto the DOS binary which unpacks
// the packed EXE and then calls the real entrypoint. So it's defined as a
// byte array, and the interesting offsets are hard-coded here. I came across
// these values and the code debugging link3216.exe built as the languages group
// did.
//
#define SegStart unpack
#define cbUnpack (*(WORD *) &unpack[6])
#define ipsave (*(WORD *) &unpack[0])
#define cssave (*(WORD *) &unpack[2])
#define spsave (*(WORD *) &unpack[8])
#define sssave (*(WORD *) &unpack[0xa])
#define cparExp (*(WORD *) &unpack[0xc])
#define raStartUnpack 0x10
#define raMoveUnpack 0x33
#define raBadStack 0
#define szBadStack 0x35
unsigned char unpack[] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x32, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x52, 0x42,
0x8b, 0xe8, 0x8c, 0xc0, 0x05, 0x10, 0x00, 0x0e,
0x1f, 0xa3, 0x04, 0x00, 0x03, 0x06, 0x0c, 0x00,
0x8e, 0xc0, 0x8b, 0x0e, 0x06, 0x00, 0x8b, 0xf9,
0x4f, 0x8b, 0xf7, 0xfd, 0xf3, 0xa4, 0x50, 0xb8,
0x34, 0x00, 0x50, 0xcb, 0x8c, 0xc3, 0x8c, 0xd8,
0x48, 0x8e, 0xd8, 0x8e, 0xc0, 0xbf, 0x0f, 0x00,
0xb9, 0x10, 0x00, 0xb0, 0xff, 0xf3, 0xae, 0x47,
0x8b, 0xf7, 0x8b, 0xc3, 0x48, 0x8e, 0xc0, 0xbf,
0x0f, 0x00, 0xb1, 0x04, 0x8b, 0xc6, 0xf7, 0xd0,
0xd3, 0xe8, 0x8c, 0xda, 0x2b, 0xd0, 0x73, 0x04,
0x8c, 0xd8, 0x2b, 0xd2, 0xd3, 0xe0, 0x03, 0xf0,
0x8e, 0xda, 0x8b, 0xc7, 0xf7, 0xd0, 0xd3, 0xe8,
0x8c, 0xc2, 0x2b, 0xd0, 0x73, 0x04, 0x8c, 0xc0,
0x2b, 0xd2, 0xd3, 0xe0, 0x03, 0xf8, 0x8e, 0xc2,
0xac, 0x8a, 0xd0, 0x4e, 0xad, 0x8b, 0xc8, 0x46,
0x8a, 0xc2, 0x24, 0xfe, 0x3c, 0xb0, 0x75, 0x05,
0xac, 0xf3, 0xaa, 0xeb, 0x06, 0x3c, 0xb2, 0x75,
0x6d, 0xf3, 0xa4, 0x8a, 0xc2, 0xa8, 0x01, 0x74,
0xb1, 0xbe, 0x32, 0x01, 0x0e, 0x1f, 0x8b, 0x1e,
0x04, 0x00, 0xfc, 0x33, 0xd2, 0xad, 0x8b, 0xc8,
0xe3, 0x13, 0x8b, 0xc2, 0x03, 0xc3, 0x8e, 0xc0,
0xad, 0x8b, 0xf8, 0x83, 0xff, 0xff, 0x74, 0x11,
0x26, 0x01, 0x1d, 0xe2, 0xf3, 0x81, 0xfa, 0x00,
0xf0, 0x74, 0x16, 0x81, 0xc2, 0x00, 0x10, 0xeb,
0xdc, 0x8c, 0xc0, 0x40, 0x8e, 0xc0, 0x83, 0xef,
0x10, 0x26, 0x01, 0x1d, 0x48, 0x8e, 0xc0, 0xeb,
0xe2, 0x8b, 0xc3, 0x8b, 0x3e, 0x08, 0x00, 0x8b,
0x36, 0x0a, 0x00, 0x03, 0xf0, 0x01, 0x06, 0x02,
0x00, 0x2d, 0x10, 0x00, 0x8e, 0xd8, 0x8e, 0xc0,
0xbb, 0x00, 0x00, 0xfa, 0x8e, 0xd6, 0x8b, 0xe7,
0xfb, 0x8b, 0xc5, 0x2e, 0xff, 0x2f, 0xb4, 0x40,
0xbb, 0x02, 0x00, 0xb9, 0x16, 0x00, 0x8c, 0xca,
0x8e, 0xda, 0xba, 0x1c, 0x01, 0xcd, 0x21, 0xb8,
0xff, 0x4c, 0xcd, 0x21, 0x50, 0x61, 0x63, 0x6b,
0x65, 0x64, 0x20, 0x66, 0x69, 0x6c, 0x65, 0x20,
0x69, 0x73, 0x20, 0x63, 0x6f, 0x72, 0x72, 0x75,
0x70, 0x74
};
#endif // _WIN32
LOCAL WORD lastc; /* last character */
LOCAL WORD c; /* current or next character */
LOCAL WORD State = STARTSTATE;
/* current state */
LOCAL FTYPE fEnumOK; /* OK to emit enumerated records */
LOCAL WORD cbRepeat; /* length of repeated stream */
LOCAL WORD cbEnum; /* length of enumerated stream */
#define EHLEN 3 /* 2 for length + 1 for type */
#define MAXRPT 0xfff0 /* Maximum length to compress */
#define MAXENM (0xfff0-(EHLEN+1))
/* Maximum length of enum. stream */
#define MINEXP (2*EHLEN+2) /* Minimum length of repeated stream,
* after the first repeate record */
#define toAdr20(seg, off) (((long)seg << 4) + off)
LOCAL WORD minRpt = (18 * EHLEN) + 1;
/* Minimum for rpt rec begins larger */
/* Type values for expansion record headers */
#define RPTREC 0xb0 /* Repeat record */
#define ENMREC 0xb2 /* Enumerated record */
/*
* OutPack - Run a buffer through the compactor. Return value is
* undefined.
*/
void OutPack (pb, cb)
REGISTER BYTE *pb; /* Pointer to buffer */
unsigned cb; /* Number of bytes to compress */
{
REGISTER BYTE *endp; /* Pointer to end of buffer */
endp = &pb[cb];
while (pb < endp)
switch (State)
{
case STARTSTATE:
lastc = *pb++;
State = FINDREPEAT;
break;
case FINDREPEAT:
if (cbEnum >= MAXENM)
{
EmitRecords();
State = FINDREPEAT;
break;
}
c = *pb++;
if (c == lastc)
{
cbRepeat = 2;
State = FINDENDRPT;
break;
}
/* At this point c != lastc */
fputc(lastc, bsRunfile);
cbEnum++;
lastc = c;
break;
case FINDENDRPT:
c = *pb++;
if (c == lastc && cbRepeat < MAXRPT)
{
cbRepeat++;
break;
}
if (cbRepeat < minRpt)
{
/*
* Not long enough. Enum record swallows
* repeated chars.
*/
while (cbEnum <= MAXENM && cbRepeat > 0)
{
fputc(lastc, bsRunfile);
cbEnum++;
cbRepeat--;
}
if (cbRepeat > 0)
EmitRecords();
} else
EmitRecords();
lastc = c; /* Prepare for next stream */
State = FINDREPEAT;
}
}
/*
* EmitRecords - Emits 1 or 2 expansion records. Return value is
* undefined.
*/
LOCAL void NEAR EmitRecords ()
{
/* We have 1 or 2 records to output */
if (cbEnum > 0)
{
#if MDEBUG AND FDEBUG
if (fDebug) fprintf(stdout, "E%8x\n", cbEnum);
#endif
if (fEnumOK)
{
/* Output an enumerated record header */
OutWord(cbEnum);
fputc(ENMREC, bsRunfile);
}
cbEnum = 0;
}
if (cbRepeat >= minRpt)
{
#if MDEBUG AND FDEBUG
if (fDebug) fprintf(stdout, "R%8x\n", cbRepeat);
#endif
/* Output a repeat record */
fputc(lastc, bsRunfile);
OutWord(cbRepeat);
if (!fEnumOK)
{
/* 1st record header generated */
fputc(RPTREC|1, bsRunfile);
fEnumOK = 1;
} else
fputc(RPTREC, bsRunfile);
cbRepeat = 0;
minRpt = MINEXP; /* 1st is out, so reset minRpt */
} else if (cbRepeat > 0)
{
cbEnum = cbRepeat;
while (cbRepeat-- > 0)
fputc(lastc, bsRunfile);
}
}
/*
* EndPack - End the packing procedure: add the relocator module.
*/
void EndPack (prun)
RUNTYPE *prun; /* Pointer to runfile header */
{
long fpos; /* File position */
WORD cparPacked; /* # paras in packed image */
WORD cparUnpack; /* Size of Unpack module (paras) */
int i;
int crle; /* Count of relocs for a frame */
long cTmp; /* Temporary count */
long us; /* User's stack in minalloc */
long los; /* Low end of forbidden stack */
fseek(bsRunfile, 0L, 2); /* Go to end of file */
cTmp = (((((long)prun->cpnRes-1)<<5) - prun->cparDirectory) << 4) +
(prun->cbLastp ? prun->cbLastp : 512);
/* Get # bytes in expanded image */
cbRepeat += (WORD) (0xf & (0x10 - (0xf & cTmp)));
/* Make it look like image ends on
* paragraph boundary */
if (State == FINDREPEAT)
{
fputc(lastc, bsRunfile); /* Update last enum record */
cbEnum++;
}
minRpt = 1; /* Force final repeat rec. out */
EmitRecords(); /* Output the final record(s) */
cparExp = (short) ((cTmp + 0xf) >> 4);/* Save # paras in image */
/*
* Append the unpacking module (relocator-expander)
*/
fpos = ftell(bsRunfile); /* Save where Unpack begins */
/* Align Unpack on paragraph boundary */
while (fpos & 0x0f)
{
fpos++;
fputc(0xff, bsRunfile);
}
/* Make sure User stack won't stomp on unpack code */
us = toAdr20(prun->saStack, prun->raStackInit);
los = toAdr20((cTmp >> 4), raBadStack);
while ( us > los && us - los < szBadStack )
{
for (i = 0; i < 16; i++)
{
us--;
fpos++;
fputc(0xff, bsRunfile);
}
}
fflush(bsRunfile);
cparPacked = (WORD) ((fpos >> 4) - prun->cparDirectory);
if (cTmp < ((long)cparPacked << 4) + raMoveUnpack)
Fatal(ER_badpack);
/* Append relocator module (Unpack). This code depends
* closely on the structure of unpack.asm. */
/* Get length of relocation area */
for (crle = 0, i = 0; i < 16; i++)
crle += (mpframeRlc[i].count + 1) << 1;
/* Initialize stack of relocator module */
ipsave = prun->raStart;
cssave = prun->saStart;
#if defined( _WIN32 )
if (cbUnpack != sizeof(unpack))
Fatal(ER_badpack);
#endif
i = cbUnpack;
cbUnpack += (WORD)crle;
spsave = prun->raStackInit;
sssave = prun->saStack;
#ifdef M_BYTESWAP
bswap(Unpack, 7);
#endif
#if DOSX32
WriteExe(&SegStart, i);
#else
fwrite(UnpackModule, 1, i, bsRunfile);
#endif
/* Append optimized relocation records */
for (i = 0; i < 16; i++)
{
crle = mpframeRlc[i].count;
OutWord((WORD) crle);
WriteExe(mpframeRlc[i].rgRlc, crle * sizeof(WORD));
}
/* Correct header values */
fpos += cbUnpack;
prun->cbLastp = (WORD) (fpos & 0x1ff);
prun->cpnRes = (WORD) ((fpos + 511) >> 9);
prun->irleMax = 0;
cparUnpack = (cbUnpack + 0xf) >> 4;
prun->cparMinAlloc = (cparExp + max(prun->cparMinAlloc,(cparUnpack+8)))
- (cparPacked + cparUnpack);
if (prun->cparMaxAlloc < prun->cparMinAlloc)
prun->cparMaxAlloc = prun->cparMinAlloc;
prun->saStack = cparExp + cparUnpack;
prun->raStackInit = 128;
prun->raStart = raStartUnpack;
prun->saStart = cparPacked;
fseek(bsRunfile, 0L, 0);
OutHeader((struct exe_hdr *) prun);
fseek(bsRunfile, fpos, 0);
}
#ifdef M_BYTESWAP
/*
* Swap bytes for 1st n words in buffer.
*/
LOCAL bswap (buf, n)
REGISTER char *buf;
REGISTER int n;
{
REGISTER char swapb;
for ( ; n-- > 0 ; buf += 2)
{
swapb = buf[0];
buf[0] = buf[1];
buf[1] = swapb;
}
}
#endif
#endif /*FEXEPACK AND ODOS3EXE*/
/*
* The following routines concern packing segmented-executable format
* files.
*/
#if FALSE
#define MINREPEAT 32 /* Min length of iteration cousing compression */
LOCAL long vaLast; /* Virtual address */
LOCAL long vaStart; /* Virtual scanning start address */
LOCAL long BufEnd; /* Virtual address of buffer end */
#if EXE386
LOCAL long ra; /* Offset within packed segment */
#endif
LOCAL BYTE LastB;
LOCAL BYTE CurrentB;
LOCAL long VPageAddress; /* Virtual address of current page */
LOCAL WORD VPageOffset; /* Current position within virtual page */
LOCAL BYTE *PageBuffer; /* Virtual page buffer */
LOCAL BYTE NEAR GetFromVM()
{
if (VPageOffset == PAGLEN)
{
PageBuffer = mapva(VPageAddress, FALSE);
/* Fetch page */
VPageAddress += PAGLEN; /* Update page virtual address */
VPageOffset = 0; /* Init page offset */
}
return(PageBuffer[VPageOffset++]);
}
LOCAL WORD NEAR ScanWhileSame()
{
long l;
l = 2L; /* We are looking at two bytes in buffer */
while (CurrentB == LastB)
{
if (vaStart + l >= BufEnd)
return((WORD) l); /* We bump the buffer end */
CurrentB = GetFromVM();
l++;
}
return(l == 2L ? 0 : (WORD) (l - 1));
/* We went one byte too far to detect they are different */
}
LOCAL WORD NEAR ScanWhileDifferent()
{
long l;
l = 2L; /* We are looking at two bytes in buffer */
while (CurrentB != LastB)
{
if (vaStart + l >= BufEnd)
return((WORD) l); /* We bump the buffer end */
LastB = CurrentB;
CurrentB = GetFromVM();
l++;
}
return((WORD) (l - 2)); /* We went two bytes too far to detect they are the same */
}
LOCAL WORD NEAR AfterScanning(l)
WORD l; /* Length of scanned bytes */
{
vaStart += l; /* Update scan start address */
#if EXE386
ra += l; /* Update offset in segment */
#endif
if (vaStart + 2 >= BufEnd)
{ /* We need at least to bytes remaining */
return(FALSE); /* Buffer end */
}
else
{
if (LastB != CurrentB)
{ /* We stop at iterated and enumerated */
LastB = CurrentB; /* byte sequence, so we have move */
CurrentB = GetFromVM(); /* one byte forward */
}
return((WORD) TRUE);
}
}
LOCAL void NEAR OutEnum(void)
{
#if EXE386
if (ExeFormat == Exe386)
OutVm(vaLast, vaStart - vaLast);
else
{
#endif
OutWord(1);
OutWord((WORD) (vaStart - vaLast));
OutVm(vaLast, vaStart - vaLast);
#if EXE386
}
#endif
PageBuffer = mapva((VPageAddress - PAGLEN), FALSE);
/* Refetch page */
}
LOCAL void NEAR OutIter(SATYPE sa, WORD length)
{
#if EXE386
ITER idata; /* Iterated data description for range */
if (ExeFormat == Exe386)
{
idata.iterations = (DWORD) length;
idata.length = (DWORD) 1;
idata.data = (DWORD) LastB;
UpdateRanges(ShortIterData, sa, ra, &idata);
}
else
{
#endif
OutWord(length);
OutWord(1);
OutByte(bsRunfile, LastB);
#if EXE386
}
#endif
}
/*
* Out5Pack - Run a buffer through the compactor. Return value is
* starting position where data was written to output file.
*/
long Out5Pack (sa, packed)
SATYPE sa; /* File segment to be packed */
WORD *packed; /* TRUE if iterated records written */
{
WORD proceed; /* True if there are bytes to scan */
WORD length; /* Scanned bytes length */
long lfaStart; /* Starting file address */
lfaStart = ftell(bsRunfile); /* Get the starting address */
VPageAddress = AREASA(sa);
VPageOffset = PAGLEN;
*packed = FALSE;
if (mpsacbinit[sa] > 1L)
{ /* If buffer is big enough */
#if EXE386
ra = 0L; /* Offset within segment */
#endif
vaStart = VPageAddress;
vaLast = vaStart;
BufEnd = vaStart + mpsacbinit[sa];
LastB = GetFromVM();
CurrentB = GetFromVM();
proceed = (WORD) TRUE; /* Initialize */
while (proceed)
{
length = ScanWhileDifferent();
if (!(proceed = AfterScanning(length)))
break;
if ((length = ScanWhileSame()) > MINREPEAT)
{ /* If there are enough same bytes */
if (vaLast != vaStart)
OutEnum(); /* First write out preceeding diff. bytes */
OutIter(sa, length); /* Now write out iterated record */
proceed = AfterScanning(length);
*packed = (WORD) TRUE;
vaLast = vaStart;
}
else proceed = AfterScanning(length);
/* Otherwise enumerated record swallow this */
} /* small repeated record */
}
if (*packed)
{
if (vaLast != BufEnd)
{
vaStart = BufEnd;
OutEnum(); /* Write out any remainig bytes */
}
mpsacbinit[sa] = ftell(bsRunfile) - lfaStart;
/* Return number of written bytes */
return(lfaStart);
}
else
return(OutVm(AREASA(sa),mpsacbinit[sa]));
}
#endif /*FEXEPACK AND OSEGEXE*/