finddata.c

   1 /*
   2  * finddata.c
   3  * Copyright (C) 2000-2002 A.J. van Os; Released under GPL
   4  *
   5  * Description:
   6  * Find the blocks that contain the data of MS Word files
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include "antiword.h"
  12
  13
  14 /*
  15  * bAddDataBlocks - Add the blocks to the data block list
  16  *
  17  * Returns TRUE when successful, otherwise FALSE
  18  */
  19 BOOL
  20 bAddDataBlocks(ULONG ulDataPosFirst, ULONG ulTotalLength,
  21         ULONG ulStartBlock, const ULONG *aulBBD, size_t tBBDLen)
  22 {
  23         data_block_type tDataBlock;
  24         ULONG   ulDataPos, ulOffset, ulIndex;
  25         long    lToGo;
  26         BOOL    bSuccess;
  27
  28         fail(ulTotalLength > (ULONG)LONG_MAX);
  29         fail(ulStartBlock > MAX_BLOCKNUMBER && ulStartBlock != END_OF_CHAIN);
  30         fail(aulBBD == NULL);
  31
  32         NO_DBG_HEX(ulDataPosFirst);
  33         NO_DBG_DEC(ulTotalLength);
  34
  35         lToGo = (long)ulTotalLength;
  36
  37         ulDataPos = ulDataPosFirst;
  38         ulOffset = ulDataPosFirst;
  39         for (ulIndex = ulStartBlock;
  40              ulIndex != END_OF_CHAIN && lToGo > 0;
  41              ulIndex = aulBBD[ulIndex]) {
  42                 if (ulIndex == UNUSED_BLOCK || ulIndex >= (ULONG)tBBDLen) {
  43                         DBG_DEC(ulIndex);
  44                         DBG_DEC(tBBDLen);
  45                         return FALSE;
  46                 }
  47                 if (ulOffset >= BIG_BLOCK_SIZE) {
  48                         ulOffset -= BIG_BLOCK_SIZE;
  49                         continue;
  50                 }
  51                 tDataBlock.ulFileOffset =
  52                         (ulIndex + 1) * BIG_BLOCK_SIZE + ulOffset;
  53                 tDataBlock.ulDataPos = ulDataPos;
  54                 tDataBlock.ulLength = min(BIG_BLOCK_SIZE - ulOffset,
  55                                                 (ULONG)lToGo);
  56                 fail(tDataBlock.ulLength > BIG_BLOCK_SIZE);
  57                 ulOffset = 0;
  58                 if (!bAdd2DataBlockList(&tDataBlock)) {
  59                         DBG_HEX(tDataBlock.ulFileOffset);
  60                         DBG_HEX(tDataBlock.ulDataPos);
  61                         DBG_DEC(tDataBlock.ulLength);
  62                         return FALSE;
  63                 }
  64                 ulDataPos += tDataBlock.ulLength;
  65                 lToGo -= (long)tDataBlock.ulLength;
  66         }
  67         bSuccess = lToGo == 0 ||
  68                 (ulTotalLength == (ULONG)LONG_MAX && ulIndex == END_OF_CHAIN);
  69         DBG_DEC_C(!bSuccess, lToGo);
  70         DBG_DEC_C(!bSuccess, ulTotalLength);
  71         DBG_DEC_C(!bSuccess, ulIndex);
  72         return bSuccess;
  73 } /* end of bAddDataBlocks */
  74
  75 /*
  76  * bGet6DocumentData - make a list of the data blocks of Word 6/7 files
  77  *
  78  * Code for "fast saved" files.
  79  *
  80  * Returns TRUE when successful, otherwise FALSE
  81  */
  82 BOOL
  83 bGet6DocumentData(FILE *pFile, ULONG ulStartBlock,
  84         const ULONG *aulBBD, size_t tBBDLen, const UCHAR *aucHeader)
  85 {
  86         UCHAR   *aucBuffer;
  87         ULONG   ulBeginTextInfo, ulOffset, ulTotLength;
  88         size_t  tTextInfoLen;
  89         int     iIndex, iOff, iType, iLen, iPieces;
  90
  91         DBG_MSG("bGet6DocumentData");
  92
  93         fail(pFile == NULL);
  94         fail(aulBBD == NULL);
  95         fail(aucHeader == NULL);
  96
  97         ulBeginTextInfo = ulGetLong(0x160, aucHeader);
  98         DBG_HEX(ulBeginTextInfo);
  99         tTextInfoLen = (size_t)ulGetLong(0x164, aucHeader);
 100         DBG_DEC(tTextInfoLen);
 101
 102         aucBuffer = xmalloc(tTextInfoLen);
 103         if (!bReadBuffer(pFile, ulStartBlock,
 104                         aulBBD, tBBDLen, BIG_BLOCK_SIZE,
 105                         aucBuffer, ulBeginTextInfo, tTextInfoLen)) {
 106                 aucBuffer = xfree(aucBuffer);
 107                 return FALSE;
 108         }
 109         NO_DBG_PRINT_BLOCK(aucBuffer, tTextInfoLen);
 110
 111         iOff = 0;
 112         while (iOff < (int)tTextInfoLen) {
 113                 iType = (int)ucGetByte(iOff, aucBuffer);
 114                 iOff++;
 115                 if (iType == 0) {
 116                         iOff++;
 117                         continue;
 118                 }
 119                 iLen = (int)usGetWord(iOff, aucBuffer);
 120                 iOff += 2;
 121                 if (iType == 1) {
 122                         iOff += iLen;
 123                         continue;
 124                 }
 125                 if (iType != 2) {
 126                         werr(0, "Unknown type of 'fastsaved' format");
 127                         aucBuffer = xfree(aucBuffer);
 128                         return FALSE;
 129                 }
 130                 /* Type 2 */
 131                 NO_DBG_DEC(iLen);
 132                 iOff += 2;
 133                 iPieces = (iLen - 4) / 12;
 134                 DBG_DEC(iPieces);
 135                 for (iIndex = 0; iIndex < iPieces; iIndex++) {
 136                         ulOffset = ulGetLong(
 137                                 iOff + (iPieces + 1) * 4 + iIndex * 8 + 2,
 138                                 aucBuffer);
 139                         ulTotLength = ulGetLong(iOff + (iIndex + 1) * 4,
 140                                                 aucBuffer) -
 141                                         ulGetLong(iOff + iIndex * 4,
 142                                                 aucBuffer);
 143                         if (!bAddDataBlocks(ulOffset, ulTotLength,
 144                                         ulStartBlock,
 145                                         aulBBD, tBBDLen)) {
 146                                 aucBuffer = xfree(aucBuffer);
 147                                 return FALSE;
 148                         }
 149                 }
 150                 break;
 151         }
 152         aucBuffer = xfree(aucBuffer);
 153         return TRUE;
 154 } /* end of bGet6DocumentData */